Journal articles on the topic 'P-tau181'
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Xia, Chenyu, and Qiang Ma. "The Levels of Amyloid β-Protein and P181 in Peripheral Blood of Patients with Alzheimer’s Disease Combined with Helicobacter pylori Infection and Their Clinical Significance." Computational and Mathematical Methods in Medicine 2021 (December 20, 2021): 1–6. http://dx.doi.org/10.1155/2021/7135399.
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Objective. To analyze the levels of amyloid β-protein and P181 in peripheral blood of patients with Alzheimer’s disease combined with Helicobacter pylori infection and their clinical significance. Method. From January 2019 to June 2020, 59 patients were enrolled in this experiment including the AD group with 27 patients and the normal control group with 32 patients. The patients were divided into two groups: Alzheimer’s disease (AD) group ( n = 27 ) and control group ( n = 32 ), collecting the general data of patients, analyzing the diagnostic specificity and sensitivity of serum p-tau181 and Aβ42 and their influence on prognosis, and comparing the serum Aβ42 and p-tau181 concentrations for different HP infection degrees. Result. Single diagnostic sensitivity of Aβ42, p-tau181, and Aβ42 combined p-tau181 was 0.863, 0.854, and 0.972, respectively, and their specificity was 0.048, 0.206, and 0.305, respectively. Compared with the single diagnosis of serum Aβ42 and p-tau181, the combined diagnosis has higher sensitivity and specificity ( P < 0.05 ); age, years of education, serum Aβ42, and p-tau181 are factors affecting the prognosis of patients with Alzheimer’s disease combined with Helicobacter pylori infection; the concentration of Aβ42 in the control group was higher than that in the AD group, there was a statistical difference in the Aβ42 concentration between the two groups ( P < 0.05 ), and there was no statistical difference in the concentration of p-tau181 between the two groups ( P > 0.05 ); the HP positive infection rate of the AD group and the control group was 63.0% and 35.7%, respectively. The HP negative infection rate of the AD group and the control group was 37.0% and 64.3%, respectively. Compared with the control group, the positive rate of HP in the AD group was higher, and the difference was statistically significant ( P < 0.05 ); compared with HP-negative patients, HP-positive patients had a higher Aβ42 concentration, and the difference was statistically significant ( P < 0.05 ). The concentration of p-tau181 in the two groups was not statistically significant ( P > 0.05 ); Aβ42 gradually increases with increasing HP infection degree, and there are significant differences in serum Aβ42 levels between different degrees of infection. However, the level of serum p-tau181 does not change significantly with the increase of infection. Conclusion. There are significant alterations in the expression levels of Aβ42 and p-tau181 in peripheral blood of AD patients, and the levels of Aβ42 are related to HP infection; Aβ42 and p-tau181 are potential biomarkers for AD diagnosis and treatment.
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Benussi, Alberto, Thomas K. Karikari, Nicholas Ashton, Stefano Gazzina, Enrico Premi, Luisa Benussi, Roberta Ghidoni, et al. "Diagnostic and prognostic value of serum NfL and p-Tau181 in frontotemporal lobar degeneration." Journal of Neurology, Neurosurgery & Psychiatry 91, no. 9 (July 1, 2020): 960–67. http://dx.doi.org/10.1136/jnnp-2020-323487.
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ObjectiveTo assess the diagnostic and prognostic value of serum neurofilament light (NfL) and serum phospho-Tau181 (p-Tau181) in a large cohort of patients with frontotemporal lobar degeneration (FTLD).MethodsIn this retrospective study, performed on 417 participants, we analysed serum NfL and p-Tau181 concentrations with an ultrasensitive single molecule array (Simoa) approach. We assessed the diagnostic values of serum biomarkers in the differential diagnosis between FTLD, Alzheimer’s disease (AD) and healthy ageing; their role as markers of disease severity assessing the correlation with clinical variables, cross-sectional brain imaging and neurophysiological data; their role as prognostic markers, considering their ability to predict survival probability in FTLD.ResultsWe observed significantly higher levels of serum NfL in patients with FTLD syndromes, compared with healthy controls, and lower levels of p-Tau181 compared with patients with AD. Serum NfL concentrations showed a high accuracy in discriminating between FTLD and healthy controls (area under the curve (AUC): 0.86, p<0.001), while serum p-Tau181 showed high accuracy in differentiating FTLD from patients with AD (AUC: 0.93, p<0.001). In FTLD, serum NfL levels correlated with measures of cognitive function, disease severity and behavioural disturbances and were associated with frontotemporal atrophy and indirect measures of GABAergic deficit. Moreover, serum NfL concentrations were identified as the best predictors of survival probability.ConclusionsThe assessment of serum NfL and p-Tau181 may provide a comprehensive view of FTLD, aiding in the differential diagnosis, in staging disease severity and in defining survival probability.
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Salami, Alireza, Rolf Adolfsson, Micael Andersson, Kaj Blennow, Anders Lundquist, Annelie Nordin Adolfsson, Michael Schöll, Henrik Zetterberg, and Lars Nyberg. "Association of APOE ɛ4 and Plasma p-tau181 with Preclinical Alzheimer’s Disease and Longitudinal Change in Hippocampus Function." Journal of Alzheimer's Disease 85, no. 3 (February 1, 2022): 1309–20. http://dx.doi.org/10.3233/jad-210673.
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Background: The Apolipoprotein E (APOE) ɛ4 allele has been linked to increased tau phosphorylation and tangle formation. APOE ɛ4 carriers with elevated tau might be at the higher risk for Alzheimer’s disease (AD) progression. Previous studies showed that tau pathology begins early in areas of the medial temporal lobe. Similarly, APOE ɛ4 carriers showed altered hippocampal functional integrity. However, it remains unknown whether the influence of elevated tau accumulation on hippocampal functional changes would be more pronounced for APOE ɛ4 carriers. Objective: We related ɛ4 carriage to levels of plasma phosphorylated tau (p-tau181) up to 15 years prior to AD onset. Furthermore, elevated p-tau181 was explored in relation to longitudinal changes in hippocampal function and connectivity. Methods: Plasma p-tau181 was analyzed in 142 clinically defined AD cases and 126 matched controls. The longitudinal analysis involved 87 non-demented individuals (from population-based study) with two waves of plasma samples and three waves of functional magnetic resonance imaging during rest and memory encoding. Results: Increased p-tau181 was observed for both ɛ4 carriers and non-carriers close to AD onset, but exclusively for ɛ4 carriers in the early preclinical groups (7- and 13-years pre-AD). In ɛ4 carriers, longitudinal p-tau181 increase was paralleled by elevated local hippocampal connectivity at rest and subsequent reduction of hippocampus encoding-related activity. Conclusion: Our findings support an association of APOE ɛ4 and p-tau181 with preclinical AD and hippocampus functioning.
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Trelle, Alexandra N., Valerie A. Carr, Edward N. Wilson, Michelle S. Swarovski, Madison P. Hunt, Tyler N. Toueg, Tammy T. Tran, et al. "Association of CSF Biomarkers With Hippocampal-Dependent Memory in Preclinical Alzheimer Disease." Neurology 96, no. 10 (January 6, 2021): e1470-e1481. http://dx.doi.org/10.1212/wnl.0000000000011477.
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ObjectiveTo determine whether memory tasks with demonstrated sensitivity to hippocampal function can detect variance related to preclinical Alzheimer disease (AD) biomarkers, we examined associations between performance in 3 memory tasks and CSF β-amyloid (Aβ)42/Aβ40 and phosopho-tau181 (p-tau181) in cognitively unimpaired older adults (CU).MethodsCU enrolled in the Stanford Aging and Memory Study (n = 153; age 68.78 ± 5.81 years; 94 female) completed a lumbar puncture and memory assessments. CSF Aβ42, Aβ40, and p-tau181 were measured with the automated Lumipulse G system in a single-batch analysis. Episodic memory was assayed using a standardized delayed recall composite, paired associate (word–picture) cued recall, and a mnemonic discrimination task that involves discrimination between studied “target” objects, novel “foil” objects, and perceptually similar “lure” objects. Analyses examined cross-sectional relationships among memory performance, age, and CSF measures, controlling for sex and education.ResultsAge and lower Aβ42/Aβ40 were independently associated with elevated p-tau181. Age, Aβ42/Aβ40, and p-tau181 were each associated with (1) poorer associative memory and (2) diminished improvement in mnemonic discrimination performance across levels of decreased task difficulty (i.e., target–lure similarity). P-tau mediated the effect of Aβ42/Aβ40 on memory. Relationships between CSF proteins and delayed recall were similar but nonsignificant. CSF Aβ42 was not significantly associated with p-tau181 or memory.ConclusionsTests designed to tax hippocampal function are sensitive to subtle individual differences in memory among CU and correlate with early AD-associated biomarker changes in CSF. These tests may offer utility for identifying CU with preclinical AD pathology.
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Li, Ge, Cynthia L. Mayer, Daniel Morelli, Steven P. Millard, Wendy H. Raskind, Eric C. Petrie, Monique Cherrier, Anne M. Fagan, Murray A. Raskind, and Elaine R. Peskind. "Effect of simvastatin on CSF Alzheimer disease biomarkers in cognitively normal adults." Neurology 89, no. 12 (August 18, 2017): 1251–55. http://dx.doi.org/10.1212/wnl.0000000000004392.
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Objective:To examine potential disease-modifying effects of statin drugs, we conducted a 12-month randomized, placebo-controlled clinical trial of simvastatin in cognitively normal adults using change in CSF Alzheimer disease biomarkers as primary outcome measure.Methods:Participants were 45–64 years old and statin-naive with normal cognition and normal or mildly elevated cholesterol. Forty-six participants completed the 1-year study per protocol (25 in the simvastatin and 21 in the placebo group). Simvastatin was titrated to 40 mg/d. CSF Aβ42, total tau, and p-tau181 were measured at baseline and after 12 months of treatment using the INNO-BIA AlzBio3 assay. We used analysis of covariance to assess differences in biomarker change from baseline between treatment groups, adjusting for age, sex, and APOE ε4 status.Results:Changes from baseline did not differ significantly between treatment groups for any CSF biomarker, with p values of 0.53, 0.36, and 0.25 for CSF Aβ42, total tau, and p-tau181, respectively. There was no significant modifying effect of sex, APOE ε4, or baseline high-density lipoprotein or triglycerides on treatment group for any of the biomarkers (all p > 0.18). However, a significant interaction between treatment group and baseline low-density lipoprotein (LDL) was observed for p-tau181 (p = 0.003), where greater decreases from baseline in CSF p-tau181 concentrations were associated with higher baseline LDL level for the simvastatin group.Conclusions:Simvastatin-related reductions in CSF p-tau181 concentrations may be modulated by LDL cholesterol. The potential disease-modifying effects of simvastatin on CSF phospho-tau should be further investigated in persons with hypercholesterolemia.
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Maarouf, Chera L., Thomas G. Beach, Charles H. Adler, Michael Malek-Ahmadi, Tyler A. Kokjohn, Brittany N. Dugger, Douglas G. Walker, et al. "Quantitative Appraisal of Ventricular Cerebrospinal Fluid Biomarkers in Neuropathologically Diagnosed Parkinson's Disease Cases Lacking Alzheimer's Disease Pathology." Biomarker Insights 8 (January 2013): BMI.S11422. http://dx.doi.org/10.4137/bmi.s11422.
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Identifying biomarkers that distinguish Parkinson's disease (PD) from normal control (NC) individuals has the potential to increase diagnostic sensitivity for the detection of early-stage PD. A previous proteomic study identified potential biomarkers in postmortem ventricular cerebrospinal fluid (V-CSF) from neuropathologically diagnosed PD subjects lacking Alzheimer's disease (AD) neuropathology. In the present study, we assessed these biomarkers as well as p-tau181, Aβ42, and S100B by ELISA in PD (n = 43) and NC (n = 49) cases. The p-tau181/Aβ42 ratio and ApoA-1 showed statistically significant differences between groups. Multiple regression analysis demonstrated that p-tau181/Aβ42 had a significant odds ratio: OR = 1.42 (95% confidence interval [CI], 1.12–1.84), P = 0.006. Among the molecules investigated, intriguing correlations were observed that require further investigation. Our results suggest coexistent AD CSF biomarkers within the PD group notwithstanding that it was selected to minimize AD neuropathological lesions.
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Arcaro, Marina, Chiara Fenoglio, Maria Serpente, Andrea Arighi, Giorgio G. Fumagalli, Luca Sacchi, Stefano Floro, et al. "A Novel Automated Chemiluminescence Method for Detecting Cerebrospinal Fluid Amyloid-Beta 1-42 and 1-40, Total Tau and Phosphorylated-Tau: Implications for Improving Diagnostic Performance in Alzheimer’s Disease." Biomedicines 10, no. 10 (October 21, 2022): 2667. http://dx.doi.org/10.3390/biomedicines10102667.
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Recently, a fully automated instrument for the detection of the Cerebrospinal Fluid (CSF) biomarker for Alzheimer’s disease (AD) (low concentration of Amyloid-beta 42 (Aβ42), high concentration of total tau (T-tau) and Phosphorylated-tau (P-tau181)), has been implemented, namely CLEIA. We conducted a comparative analysis between ELISA and CLEIA methods in order to evaluate the analytical precision and the diagnostic performance of the novel CLEIA system on 111 CSF samples. Results confirmed a robust correlation between ELISA and CLEIA methods, with an improvement of the accuracy with the new CLEIA methodology in the detection of the single biomarkers and in their ratio values. For Aβ42 regression analysis with Passing–Bablok showed a Pearson correlation coefficient r = 0.867 (0.8120; 0.907% 95% CI p < 0.0001), T-tau analysis: r = 0.968 (0.954; 0.978% 95% CI p < 0.0001) and P-tau181: r = 0.946 (0.922; 0.962 5% 95% CI p < 0.0001). The overall ROC AUC comparison between ROC in ELISA and ROC in CLEIA confirmed a more accurate ROC AUC with the new automatic method: T-tau AUC ELISA = 0.94 (95% CI 0.89; 0.99 p < 0.0001) vs. AUC CLEIA = 0.95 (95% CI 0.89; 1.00 p < 0.0001), and P-tau181 AUC ELISA = 0.91 (95% CI 0.85; 0.98 p < 0.0001) vs. AUC CLEIA = 0.98 (95% CI 0.95; 1.00 p < 0.0001). The performance of the new CLEIA method in automation is comparable and, for tau and P-tau181, even better, as compared with standard ELISA. Hopefully, in the future, automation could be useful in clinical diagnosis and also in the context of clinical studies.
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Ewers, Michael, Nicolai Franzmeier, Marc Suárez-Calvet, Estrella Morenas-Rodriguez, Miguel Angel Araque Caballero, Gernot Kleinberger, Laura Piccio, et al. "Increased soluble TREM2 in cerebrospinal fluid is associated with reduced cognitive and clinical decline in Alzheimer’s disease." Science Translational Medicine 11, no. 507 (August 28, 2019): eaav6221. http://dx.doi.org/10.1126/scitranslmed.aav6221.
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Loss of function of TREM2, a key receptor selectively expressed by microglia in the brain, contributes to the development of Alzheimer’s disease (AD). We therefore examined whether soluble TREM2 (sTREM2) concentrations in cerebrospinal fluid (CSF) were associated with reduced rates of cognitive decline and clinical progression in subjects with AD or mild cognitive impairment (MCI). We measured sTREM2 in CSF samples from 385 elderly subjects, including cognitively normal controls, individuals with MCI, and subjects with AD dementia (follow-up period: mean, 4 years; range 1.5 to 11.5 years). In subjects with AD defined by evidence of CSF Aβ1–42 (amyloid β-peptide 1 to 42; A+) and CSF p-tau181 (tau phosphorylated on amino acid residue 181; T+), higher sTREM2 concentrations in CSF at baseline were associated with attenuated decline in memory and cognition. When analyzed in clinical subgroups, an association between higher CSF sTREM2 concentrations and subsequent reduced memory decline was consistently observed in individuals with MCI or AD dementia, who were positive for CSF Aβ1–42 and CSF p-tau181 (A+T+). Regarding clinical progression, a higher ratio of CSF sTREM2 to CSF p-tau181 concentrations predicted slower conversion from cognitively normal to symptomatic stages or from MCI to AD dementia in the subjects who were positive for CSF Aβ1–42 and CSF p-tau181. These results suggest that sTREM2 is associated with attenuated cognitive and clinical decline, a finding with important implications for future clinical trials targeting the innate immune response in AD.
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Santangelo, Roberto, Alessandro Dell'Edera, Arianna Sala, Giordano Cecchetti, Federico Masserini, Francesca Caso, Patrizia Pinto, et al. "The CSF p-tau181/Aβ42 Ratio Offers a Good Accuracy “In Vivo” in the Differential Diagnosis of Alzheimer’s Dementia." Current Alzheimer Research 16, no. 7 (September 4, 2019): 587–95. http://dx.doi.org/10.2174/1567205016666190725150836.
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Background: The incoming disease-modifying therapies against Alzheimer’s disease (AD) require reliable diagnostic markers to correctly enroll patients all over the world. CSF AD biomarkers, namely amyloid-β 42 (Aβ42), total tau (t-tau), and tau phosphorylated at threonine 181 (p-tau181), showed good diagnostic accuracy in detecting AD pathology, but their real usefulness in daily clinical practice is still a matter of debate. Therefore, further validation in complex clinical settings, that is patients with different types of dementia, is needed to uphold their future worldwide adoption. Methods: We measured CSF AD biomarkers’ concentrations in a sample of 526 patients with a clinical diagnosis of dementia (277 with AD and 249 with Other Type of Dementia, OTD). Brain FDG-PET was also considered in a subsample of 54 patients with a mismatch between the clinical diagnosis and the CSF findings. Results: A p-tau181/Aβ42 ratio higher than 0.13 showed the best diagnostic performance in differentiating AD from OTD (86% accuracy index, 74% sensitivity, 81% specificity). In cases with a mismatch between clinical diagnosis and CSF findings, brain FDG-PET partially agreed with the p-tau181/Aβ42 ratio, thus determining an increase in CSF accuracy. Conclusions: The p-tau181/Aβ42 ratio alone might reliably detect AD pathology in heterogeneous samples of patients suffering from different types of dementia. It might constitute a simple, cost-effective and reproducible in vivo proxy of AD suitable to be adopted worldwide not only in daily clinical practice but also in future experimental trials, to avoid the enrolment of misdiagnosed AD patients.
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Meyer, Pierre‐François, Nicholas J. Ashton, Thomas K. Karikari, Cherie Strikwerda‐Brown, Theresa Köbe, Julie Gonneaud, Alexa Pichet Binette, et al. "Plasma p‐tau231, p‐tau181, PET Biomarkers, and Cognitive Change in Older Adults." Annals of Neurology 91, no. 4 (February 18, 2022): 548–60. http://dx.doi.org/10.1002/ana.26308.
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Smirnov, Denis S., Nicholas J. Ashton, Kaj Blennow, Henrik Zetterberg, Joel Simrén, Juan Lantero-Rodriguez, Thomas K. Karikari, et al. "Plasma biomarkers for Alzheimer’s Disease in relation to neuropathology and cognitive change." Acta Neuropathologica 143, no. 4 (February 23, 2022): 487–503. http://dx.doi.org/10.1007/s00401-022-02408-5.
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AbstractPlasma biomarkers related to amyloid, tau, and neurodegeneration (ATN) show great promise for identifying these pathological features of Alzheimer’s Disease (AD) as shown by recent clinical studies and selected autopsy studies. We have evaluated ATN plasma biomarkers in a series of 312 well-characterized longitudinally followed research subjects with plasma available within 5 years or less before autopsy and examined these biomarkers in relation to a spectrum of AD and related pathologies. Plasma Aβ42, Aβ40, total Tau, P-tau181, P-tau231 and neurofilament light (NfL) were measured using Single molecule array (Simoa) assays. Neuropathological findings were assessed using standard research protocols. Comparing plasma biomarkers with pathology diagnoses and ratings, we found that P-tau181 (AUC = 0.856) and P-tau231 (AUC = 0.773) showed the strongest overall sensitivity and specificity for AD neuropathological change (ADNC). Plasma P-tau231 showed increases at earlier ADNC stages than other biomarkers. Plasma Aβ42/40 was decreased in relation to amyloid and AD pathology, with modest diagnostic accuracy (AUC = 0.601). NfL was increased in non-AD cases and in a subset of those with ADNC. Plasma biomarkers did not show changes in Lewy body disease (LBD), hippocampal sclerosis of aging (HS) or limbic-predominant age-related TDP-43 encephalopathy (LATE) unless ADNC was present. Higher levels of P-tau181, 231 and NfL predicted faster cognitive decline, as early as 10 years prior to autopsy, even among people with normal cognition or mild cognitive impairment. These results support plasma P-tau181 and 231 as diagnostic biomarkers related to ADNC that also can help to predict future cognitive decline, even in predementia stages. Although NfL was not consistently increased in plasma in AD and shows increases in several neurological disorders, it had utility to predict cognitive decline. Plasma Aβ42/40 as measured in this study was a relatively weak predictor of amyloid pathology, and different assay methods may be needed to improve on this. Additional plasma biomarkers are needed to detect the presence and impact of LBD and LATE pathology.
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Park, Jung Eun, Kyu Yeong Choi, Byeong C. Kim, Seong-Min Choi, Min-Kyung Song, Jang Jae Lee, Jahae Kim, et al. "Cerebrospinal Fluid Biomarkers for the Diagnosis of Prodromal Alzheimer’s Disease in Amnestic Mild Cognitive Impairment." Dementia and Geriatric Cognitive Disorders Extra 9, no. 1 (March 12, 2019): 100–113. http://dx.doi.org/10.1159/000496920.
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Background/Aims: Disease-modifying therapy for Alzheimer’s disease (AD) has led to a need for biomarkers to identify prodromal AD and very early stage of AD dementia. We aimed to identify the cutoff values of cerebrospinal fluid (CSF) biomarkers for detecting prodromal AD. Methods: We assessed 56 patients with amnestic mild cognitive impairment (aMCI) who underwent lumbar puncture. Additionally, 87 healthy elderly individuals and 34 patients with AD dementia served as controls. Positron emission tomography was performed using florbetaben as a probe. We analyzed the concentration of Aβ1–42, total tau protein (t-Tau), and tau protein phosphorylated at threonine 181 (p-Tau181) in CSF with INNOTEST enzyme-linked immunosorbent assay. Results: For the detection of prodromal AD in patients with aMCI, the cutoff values of CSF Aβ1–42, t-Tau, and p-Tau181 were 749.5 pg/mL, 225.6 pg/mL, and 43.5 pg/mL, respectively. To discriminate prodromal AD in patients with aMCI, the t-Tau/Aβ1–42 and p-Tau181/Aβ1–42 ratios defined cutoff values at 0.298 and 0.059, respectively. Conclusions: CSF biomarkers are very useful tools for the differential diagnosis of prodromal AD in aMCI patients. The concentration of CSF biomarkers is well correlated with the stages of the AD spectrum.
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Álvarez-Sánchez, Lourdes, Carmen Peña-Bautista, Laura Ferré-González, Angel Balaguer, Miguel Baquero, Bonaventura Casanova-Estruch, and Consuelo Cháfer-Pericás. "Assessment of Plasma and Cerebrospinal Fluid Biomarkers in Different Stages of Alzheimer’s Disease and Frontotemporal Dementia." International Journal of Molecular Sciences 24, no. 2 (January 8, 2023): 1226. http://dx.doi.org/10.3390/ijms24021226.
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Alzheimer’s disease (AD) is the primary type of dementia, followed by frontotemporal lobar degeneration (FTLD). They share some clinical characteristics, mainly at the early stages. So, the identification of early, specific, and minimally invasive biomarkers is required. In this study, some plasma biomarkers (Amyloid β42, p-Tau181, t-Tau, neurofilament light (NfL), TAR DNA-binding protein 43 (TDP-43)) were determined by single molecule array technology (SIMOA®) in control subjects (n = 22), mild cognitive impairment due to AD (MCI-AD, n = 33), mild dementia due to AD (n = 12), and FTLD (n = 11) patients. The correlations between plasma and cerebrospinal fluid (CSF) levels and the accuracy of plasma biomarkers for AD early diagnosis and discriminating from FTLD were analyzed. As result, plasma p-Tau181 and NfL levels correlated with the corresponding CSF levels. Additionally, plasma p-Tau181 showed good accuracy for distinguishing between the controls and AD, as well as discriminating between AD and FTLD. Moreover, plasma NfL could discriminate dementia-AD vs. controls, FTLD vs. controls, and MCI-AD vs. dementia-AD. Therefore, the determination of these biomarkers in plasma is potentially helpful in AD spectrum diagnosis, but also discriminating from FTLD. In addition, the accessibility of these potential early and specific biomarkers may be useful for AD screening protocols in the future.
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Ashton, Nicholas J., Tharick A. Pascoal, Thomas K. Karikari, Andréa L. Benedet, Juan Lantero-Rodriguez, Gunnar Brinkmalm, Anniina Snellman, et al. "Plasma p-tau231: a new biomarker for incipient Alzheimer’s disease pathology." Acta Neuropathologica 141, no. 5 (February 14, 2021): 709–24. http://dx.doi.org/10.1007/s00401-021-02275-6.
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AbstractThe quantification of phosphorylated tau in biofluids, either cerebrospinal fluid (CSF) or plasma, has shown great promise in detecting Alzheimer’s disease (AD) pathophysiology. Tau phosphorylated at threonine 231 (p-tau231) is one such biomarker in CSF but its usefulness as a blood biomarker is currently unknown. Here, we developed an ultrasensitive Single molecule array (Simoa) for the quantification of plasma p-tau231 which was validated in four independent cohorts (n = 588) in different settings, including the full AD continuum and non-AD neurodegenerative disorders. Plasma p-tau231 was able to identify patients with AD and differentiate them from amyloid-β negative cognitively unimpaired (CU) older adults with high accuracy (AUC = 0.92–0.94). Plasma p-tau231 also distinguished AD patients from patients with non-AD neurodegenerative disorders (AUC = 0.93), as well as from amyloid-β negative MCI patients (AUC = 0.89). In a neuropathology cohort, plasma p-tau231 in samples taken on avergae 4.2 years prior to post-mortem very accurately identified AD neuropathology in comparison to non-AD neurodegenerative disorders (AUC = 0.99), this is despite all patients being given an AD dementia diagnosis during life. Plasma p-tau231 was highly correlated with CSF p-tau231, tau pathology as assessed by [18F]MK-6240 positron emission tomography (PET), and brain amyloidosis by [18F]AZD469 PET. Remarkably, the inflection point of plasma p-tau231, increasing as a function of continuous [18F]AZD469 amyloid-β PET standardized uptake value ratio, was shown to be earlier than standard thresholds of amyloid-β PET positivity and the increase of plasma p-tau181. Furthermore, plasma p-tau231 was significantly increased in amyloid-β PET quartiles 2–4, whereas CSF p-tau217 and plasma p-tau181 increased only at quartiles 3–4 and 4, respectively. Finally, plasma p-tau231 differentiated individuals across the entire Braak stage spectrum, including Braak staging from Braak 0 through Braak I–II, which was not observed for plasma p-tau181. To conclude, this novel plasma p-tau231 assay identifies the clinical stages of AD and neuropathology equally well as plasma p-tau181, but increases earlier, already with subtle amyloid-β deposition, prior to the threshold for amyloid-β PET positivity has been attained, and also in response to early brain tau deposition. Thus, plasma p-tau231 is a promising novel biomarker of emerging AD pathology with the potential to facilitate clinical trials to identify vulnerable populations below PET threshold of amyloid-β positivity or apparent entorhinal tau deposition.
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Rizzi, Liara, Marcelle Maria Portal, Carlos Eduardo Alves Batista, Luciane Missiaggia, and Matheus Roriz-Cruz. "CSF Aβ1–42, but not p-Tau181, differentiates aMCI from SCI." Brain Research 1678 (January 2018): 27–31. http://dx.doi.org/10.1016/j.brainres.2017.10.008.
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Singh, Kailash, Bernard MY Cheung, and Aimin Xu. "Ultrasensitive detection of blood biomarkers of Alzheimer's and Parkinson's diseases: a systematic review." Biomarkers in Medicine 15, no. 17 (December 2021): 1693–708. http://dx.doi.org/10.2217/bmm-2021-0219.
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Purpose: Neurodegenerative disorders are a global health burden with costly and invasive diagnoses relying on brain imaging technology or CSF-based biomarkers. Therefore, considerable efforts to identify blood-biomarkers for Alzheimer's (AD) and Parkinson's diseases (PD) are ongoing. Objectives: This review evaluates the blood biomarkers for AD and PD for their diagnostic value. Methods: This study systematically reviewed articles published between July 1984 and February 2021. Among 1266 papers, we selected 42 studies for a systematic review and 23 studies for meta-analysis. Results & conclusion: Our analysis highlights P-tau181, T-tau and Nfl as promising blood biomarkers for AD diagnosis. Nfl levels were consistently raised in 16 AD and three PD cohorts. P-tau181 and T-tau were also significantly increased in 12 and eight AD cohorts, respectively.
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Tzartos, John S., Fotini Boufidou, Christos Stergiou, Jens Kuhle, Eline Willemse, Lina Palaiodimou, Ioanna Tsantzali, et al. "Plasma P-Tau181 for the Discrimination of Alzheimer’s Disease from Other Primary Dementing and/or Movement Disorders." Biomolecules 12, no. 8 (August 10, 2022): 1099. http://dx.doi.org/10.3390/biom12081099.
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Blood phospho-tau181 may offer a useful biomarker for Alzheimer’s disease. However, the use of either serum or plasma phospho-tau181 and their diagnostic value are currently under intense investigation. In a pilot study, we measured both serum and plasma phospho-tau181 (pT181-Tau) by single molecule array (Simoa) in a group of patients with Alzheimer’s disease and a mixed group of patients with other primary dementing and/or movement disorders. Classical cerebrospinal fluid biomarkers were also measured. Plasma (but not serum) pT181-Tau showed a significant increase in Alzheimer’s disease and correlated significantly with cerebrospinal fluid amyloid and pT181-Tau. Receiver operating curve analysis revealed a significant discrimination of Alzheimer’s from non-Alzheimer’s disease patients, with an area under the curve of 0.83 and an excellent sensitivity but a moderate specificity. Plasma pT181-Tau is not an established diagnostic biomarker for Alzheimer’s disease, but it could become one in the future, or it may serve as a screening tool for specific cases of patients or presymptomatic subjects.
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Koychev, Ivan, Katrin Jansen, Alina Dette, Liu Shi, and Heinz Holling. "Blood-Based ATN Biomarkers of Alzheimer’s Disease: A Meta-Analysis." Journal of Alzheimer's Disease 79, no. 1 (January 5, 2021): 177–95. http://dx.doi.org/10.3233/jad-200900.
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Background: The Amyloid Tau Neurodegeneration (ATN) framework was proposed to define the biological state underpinning Alzheimer’s disease (AD). Blood-based biomarkers offer a scalable alternative to the costly and invasive currently available biomarkers. Objective: In this meta-analysis we sought to assess the diagnostic performance of plasma amyloid (Aβ40, Aβ42, Aβ42/40 ratio), tangle (p-tau181), and neurodegeneration (total tau [t-tau], neurofilament light [NfL]) biomarkers. Methods: Electronic databases were screened for studies reporting biomarker concentrations for AD and control cohorts. Biomarker performance was examined by random-effect meta-analyses based on the ratio between biomarker concentrations in patients and controls. Results: 83 studies published between 1996 and 2020 were included in the analyses. Aβ42/40 ratio as well as Aβ42 discriminated AD patients from controls when using novel platforms such as immunomagnetic reduction (IMR). We found significant differences in ptau-181 concentration for studies based on single molecule array (Simoa), but not for studies based on IMR or ELISA. T-tau was significantly different between AD patients and control in IMR and Simoa but not in ELISA-based studies. In contrast, NfL differentiated between groups across platforms. Exosome studies showed strong separation between patients and controls for Aβ42, t-tau, and p-tau181. Conclusion: Currently available assays for sampling plasma ATN biomarkers appear to differentiate between AD patients and controls. Novel assay methodologies have given the field a significant boost for testing these biomarkers, such as IMR for Aβ, Simoa for p-tau181. Enriching samples through extracellular vesicles shows promise but requires further validation.
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Jiang, Lijun, Xulong Ding, Wenxiao Wang, Xiaobin Yang, Tao Li, and Peng Lei. "Head-to-Head Comparison of Different Blood Collecting Tubes for Quantification of Alzheimer’s Disease Biomarkers in Plasma." Biomolecules 12, no. 9 (August 28, 2022): 1194. http://dx.doi.org/10.3390/biom12091194.
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To examine whether the type of blood collection tubes affects the quantification of plasma biomarkers for Alzheimer’s disease analyzed with a single-molecule array (Simoa), we recruited a healthy cohort (n = 34, 11 males, mean age = 28.7 ± 7.55) and collected plasma in the following tubes: dipotassium ethylenediaminetetraacetic acid (K2-EDTA), heparin lithium (Li-Hep), and heparin sodium (Na-Hep). Plasma tau, phosphorylated tau 181 (p-tau181), amyloid β (1–40) (Aβ40), and amyloid β (1–42) (Aβ42) were quantified using Simoa. We compared the value of plasma analytes, as well as the effects of sex on the measurements. We found that plasma collected in Li-Hep and Na-Hep tubes yielded significantly higher tau and p-tau181 levels compared to plasma collected in K2-EDTA tubes from the same person, but there was no difference in the measured values of the Aβ40, Aβ42, and Aβ42/40 ratio. Therefore, the type of blood collecting tubes should be considered when planning studies that measure plasma tau.
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Blanco-Cantó, Maria Empar, J. A. Monge-Argilés, C. Pérez-Cejuela, C. Badía, L. Gabaldón, C. Muñoz-Ruíz, J. Sánchez-Payá, R. Gasparini-Berenguer, and C. Leiva-Santana. "Diagnostic Validity Comparison Between Criteria Based on CSF Alzheimer’s Disease Biomarkers." American Journal of Alzheimer's Disease & Other Dementiasr 32, no. 2 (February 13, 2017): 101–7. http://dx.doi.org/10.1177/1533317516688298.
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Aim: To compare the diagnostic validity of NIA-AA criteria, for AD CSF biomarkers, with our own new criteria. Materials and Methods: Between 2008 and 2011, 170 patients with Mild Cognitive Impairment (MCI) were included. CSF levels of Aβ1-42, T-tau, P-tau181, and ratios of T-tau/Aβ1-42 and P-tau181/Aβ1-42 were analyzed. In our criteria, we considered 3 or more abnormal variables indicative of a high likelihood of MCI due to AD. Results: After a clinical follow-up of 4.5 ± 1.2 years, 44 patients remained stable, 95 developed AD, 15 other forms of dementia, 7 died and 9 received other diagnoses. Using the NIA-AA criteria and our own criteria, the diagnostic validity of the CSF biomarkers was 58% versus 85%, specificity 84% versus 72%, PPV 82% versus 79% and NPV 61% versus 79%. Conclusion: The inclusion of the ratios in diagnostic criteria increases sensitivity and NPV for the diagnosis of MCI due to AD.
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Borroni, Barbara, Alberto Benussi, Silvana Archetti, Daniela Galimberti, Lucilla Parnetti, Benedetta Nacmias, Sandro Sorbi, Elio Scarpini, and Alessandro Padovani. "Csf p-tau181/tau ratio as biomarker for TDP pathology in frontotemporal dementia." Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration 16, no. 1-2 (October 29, 2014): 86–91. http://dx.doi.org/10.3109/21678421.2014.971812.
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Hu, W. T., K. Watts, M. Grossman, J. Glass, J. J. Lah, C. Hales, M. Shelnutt, V. Van Deerlin, J. Q. Trojanowski, and A. I. Levey. "Reduced CSF p-Tau181 to Tau ratio is a biomarker for FTLD-TDP." Neurology 81, no. 22 (October 30, 2013): 1945–52. http://dx.doi.org/10.1212/01.wnl.0000436625.63650.27.
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Gramotnev, Dmitri K., Galina Gramotnev, Alexandra Gramotnev, and Mathew J. Summers. "Path analysis of biomarkers for cognitive decline in early Parkinson’s disease." PLOS ONE 17, no. 5 (May 13, 2022): e0268379. http://dx.doi.org/10.1371/journal.pone.0268379.
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Clinical and biochemical diversity of Parkinson’s disease (PD) and numerous demographic, clinical, and pathological measures influencing cognitive function and its decline in PD create problems with the determination of effects of individual measures on cognition in PD. This is particularly the case where these measures significantly interrelate with each other producing intricate networks of direct and indirect effects on cognition. Here, we use generalized structural equation modelling (GSEM) to identify and characterize significant paths for direct and indirect effects of 14 baseline measures on global cognition in PD at baseline and at 4 years later. We consider 269 drug-naïve participants from the Parkinson’s Progression Marker Initiative database, diagnosed with idiopathic PD and observed for at least 4 years after baseline. Two GSEM networks are derived, highlighting the possibility of at least two different molecular pathways or two different PD sub-types, with either CSF p-tau181 or amyloid beta (1–42) being the primary protein variables potentially driving progression of cognitive decline. The models provide insights into the interrelations between the 14 baseline variables, and determined their total effects on cognition in early PD. High CSF amyloid concentrations (> 500 pg/ml) are associated with nearly full protection against cognitive decline in early PD in the whole range of baseline age between 40 and 80 years, and irrespectively of whether p-tau181 or amyloid beta (1–42) are considered as the primary protein variables. The total effect of depression on cognition is shown to be strongly amplified by PD, but not at the time of diagnosis or at prodromal stages. CSF p-tau181 protein could not be a reliable indicator of cognitive decline because of its significantly heterogeneous effects on cognition. The outcomes will enable better understanding of the roles of the clinical and pathological measures and their mutual effects on cognition in early PD.
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Bousiges, Olivier, Stephanie Bombois, Susanna Schraen, David Wallon, Muriel Muraine Quillard, Audrey Gabelle, Sylvain Lehmann, et al. "Cerebrospinal fluid Alzheimer biomarkers can be useful for discriminating dementia with Lewy bodies from Alzheimer’s disease at the prodromal stage." Journal of Neurology, Neurosurgery & Psychiatry 89, no. 5 (January 10, 2018): 467–75. http://dx.doi.org/10.1136/jnnp-2017-316385.
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BackgroundDifferential diagnosis between dementia with Lewy bodies (DLB) and Alzheimer’s disease (AD) is not straightforward, especially in the early stages of disease. We compared AD biomarkers (phospho-Tau181, total-Tau, Aβ42 and Aβ40) in cerebrospinal fluid (CSF) of patients with DLB and AD, focusing especially on the prodromal stage.MethodsA total of 1221 CSF were collected in different memory centres (ePLM network) in France and analysed retrospectively. Samples were obtained from patients with prodromal DLB (pro-DLB; n=57), DLB dementia (DLB-d; n=154), prodromal AD (pro-AD; n=132) and AD dementia (n=783), and control subjects (CS; n=95). These centres use the same diagnostic procedure and criteria to evaluate the patients.ResultsIn patients with pro-DLB, CSF Aβ42 levels appeared much less disrupted than in patients at the demented stage (DLB-d) (P<0.05 CS>pro-DLB; P<0.001 CS>DLB-d). On average, Aβ40 levels in patients with DLB (pro-DLB and DLB-d) were much below those in patients with pro-AD (P<0.001 DLB groups<pro-AD). The Aβ42/Aβ40 ratio in patients with pro-DLB remained close to that of CS. t-Tau and phospho-Tau181 levels were unaltered in patients with DLB (pro-DLB and DLB-d).ConclusionsReduced levels of CSF Aβ42 were found in patients with DLB but rather at a later stage, reaching those of patients with AD, in whom Aβ42 levels were decreased even at the prodromal stage. At the prodromal stage of DLB, the majority of patients presented a normal CSF profile. CSF t-Tau and phospho-Tau181 were the best biomarkers to discriminate between AD and DLB, whatever the stage of disease.
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Bucci, Marco, Konstantinos Chiotis, and Agneta Nordberg. "Alzheimer’s disease profiled by fluid and imaging markers: tau PET best predicts cognitive decline." Molecular Psychiatry 26, no. 10 (October 2021): 5888–98. http://dx.doi.org/10.1038/s41380-021-01263-2.
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AbstractFor early detection of Alzheimer’s disease, it is important to find biomarkers with predictive value for disease progression and clinical manifestations, such as cognitive decline. Individuals can now be profiled based on their biomarker status for Aβ42 (A) or tau (T) deposition and neurodegeneration (N). The aim of this study was to compare the cerebrospinal fluid (CSF) and imaging (PET/MR) biomarkers in each ATN category and to assess their ability to predict longitudinal cognitive decline. A subset of 282 patients, who had had at the same time PET investigations with amyloid-β and tau tracers, CSF sampling, and structural MRI (18% within 13 months), was selected from the ADNI dataset. The participants were grouped by clinical diagnosis at that time: cognitively normal, subjective memory concern, early or late mild cognitive impairment, or AD. Agreement between CSF (amyloid-β-1-42(A), phosphorylated-Tau181(T), total-Tau(N)), and imaging (amyloid-β PET (florbetaben and florbetapir)(A), tau PET (flortaucipir)(T), hippocampal volume (MRI)(N)) positivity in ATN was assessed with Cohen’s Kappa. Linear mixed-effects models were used to predict decline in the episodic memory. There was moderate agreement between PET and CSF for A biomarkers (Kappa = 0.39–0.71), while only fair agreement for T biomarkers (Kappa ≤ 0.40, except AD) and discordance for N biomarkers across all groups (Kappa ≤ 0.14) was found. Baseline PET tau predicted longitudinal decline in episodic memory irrespective of CSF p-Tau181 positivity (p ≤ 0.02). Baseline PET tau and amyloid-β predicted decline in episodic memory (p ≤ 0.0001), but isolated PET amyloid-β did not. Isolated PET Tau positivity was only observed in 2 participants (0.71% of the sample). While results for amyloid-β were similar using CSF or imaging, CSF and imaging results for tau and neurodegeneration were not interchangeable. PET tau positivity was superior to CSF p-Tau181 and PET amyloid-β in predicting cognitive decline in the AD continuum within 3 years of follow-up.
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Tsiknia, Amaryllis A., Steven D. Edland, Erin E. Sundermann, Emilie T. Reas, James B. Brewer, Douglas Galasko, and Sarah J. Banks. "Sex differences in plasma p-tau181 associations with Alzheimer’s disease biomarkers, cognitive decline, and clinical progression." Molecular Psychiatry, June 29, 2022. http://dx.doi.org/10.1038/s41380-022-01675-8.
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AbstractStudies have shown that women on the Alzheimer’s disease (AD) continuum have more pathological tau in the brain and cerebrospinal fluid (CSF), than men. Some studies have found that higher levels of tau biomarkers are more strongly associated with clinical AD, cognitive decline and neurodegeneration in women than in men. Despite major developments in the use of plasma tau phosphorylated at threonine 181 (p-tau181) as an AD biomarker, it is unknown whether these sex differences apply to plasma p-tau181. In 1060 Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants (47% women, 73.8 ± 7.6 years old), we examined sex differences in plasma p-tau181 levels and their association with other biomarkers, cognitive decline and incident AD. Linear regressions tested for an effect of sex on plasma p-tau181 levels and for plasma p-tau181 × sex interactions on CSF p-tau181, as well as entorhinal cortex tau, cortical amyloid-β (Aβ) deposition, and brain glucose metabolism, quantified using PET imaging. Linear mixed effects models tested for a sex × baseline plasma p-tau181 interaction on change in cognition over time. Finally, Cox models tested for a sex × plasma p-tau181 interaction on the risk of AD dementia in participants who were free of dementia at baseline. Despite similar plasma p-tau181 levels between sexes, women had lower brain glucose metabolism, greater brain Aβ and entorhinal cortex tau deposition, higher CSF p-tau181 and faster cognitive decline in relation to higher baseline plasma p-tau181 levels compared with men. Among Aβ positive, dementia-free participants, women had higher rates of incident AD dementia associated with increasing baseline plasma p-tau181 levels, relative to men. Our results suggest that sex may impact the clinical interpretation of plasma p-tau181 concentrations. If replicated, these findings could have important implications for the use of plasma p-tau181 as an accessible AD biomarker and screening tool for preventive and therapeutic clinical trials.
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Clark, Christopher, Piotr Lewczuk, Johannes Kornhuber, Jonas Richiardi, Bénédicte Maréchal, Thomas K. Karikari, Kaj Blennow, Henrik Zetterberg, and Julius Popp. "Plasma neurofilament light and phosphorylated tau 181 as biomarkers of Alzheimer’s disease pathology and clinical disease progression." Alzheimer's Research & Therapy 13, no. 1 (March 25, 2021). http://dx.doi.org/10.1186/s13195-021-00805-8.
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Abstract Background To assess the performance of plasma neurofilament light (NfL) and phosphorylated tau 181 (p-tau181) to inform about cerebral Alzheimer’s disease (AD) pathology and predict clinical progression in a memory clinic setting. Methods Plasma NfL and p-tau181, along with established cerebrospinal fluid (CSF) biomarkers of AD pathology, were measured in participants with normal cognition (CN) and memory clinic patients with cognitive impairment (mild cognitive impairment and dementia, CI). Clinical and neuropsychological assessments were performed at inclusion and follow-up visits at 18 and 36 months. Multivariate analysis assessed associations of plasma NfL and p-tau181 levels with AD, single CSF biomarkers, hippocampal volume, and clinical measures of disease progression. Results Plasma NfL levels were higher in CN participants with an AD CSF profile (defined by a CSF p-tau181/Aβ1–42 > 0.0779) as compared with CN non-AD, while p-tau181 plasma levels were higher in CI patients with AD. Plasma NfL levels correlated with CSF tau and p-tau181 in CN, and with CSF tau in CI patients. Plasma p-tau181 correlated with CSF p-tau181 in CN and with CSF tau, p-tau181, Aβ1–42, and Aβ1–42/Aβ1–40 in CI participants. Compared with a reference model, adding plasma p-tau181 improved the prediction of AD in CI patients while adding NfL did not. Adding p-tau181, but not NfL levels, to a reference model improved prediction of cognitive decline in CI participants. Conclusion Plasma NfL indicates neurodegeneration while plasma p-tau181 levels can serve as a biomarker of cerebral AD pathology and cognitive decline. Their predictive performance depends on the presence of cognitive impairment.
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Shen, Xue-Ning, Yu-Yuan Huang, Shi-Dong Chen, Yu Guo, Lan Tan, Qiang Dong, Jin-Tai Yu, et al. "Plasma phosphorylated-tau181 as a predictive biomarker for Alzheimer’s amyloid, tau and FDG PET status." Translational Psychiatry 11, no. 1 (November 13, 2021). http://dx.doi.org/10.1038/s41398-021-01709-9.
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AbstractPlasma phosphorylated-tau181 (p-tau181) showed the potential for Alzheimer’s diagnosis and prognosis, but its role in detecting cerebral pathologies is unclear. We aimed to evaluate whether it could serve as a marker for Alzheimer’s pathology in the brain. A total of 1189 participants with plasma p-tau181 and PET data of amyloid, tau or FDG PET were included from ADNI. Cross-sectional relationships of plasma p-tau181 with PET biomarkers were tested. Longitudinally, we further investigated whether different p-tau181 levels at baseline predicted different progression of Alzheimer’s pathological changes in the brain. We found plasma p-tau181 significantly correlated with brain amyloid (Spearman ρ = 0.45, P < 0.0001), tau (0.25, P = 0.0003), and FDG PET uptakes (−0.37, P < 0.0001), and increased along the Alzheimer’s continuum. Individually, plasma p-tau181 could detect abnormal amyloid, tau pathologies and hypometabolism in the brain, similar with or even better than clinical indicators. The diagnostic accuracy of plasma p-tau181 elevated significantly when combined with clinical information (AUC = 0.814 for amyloid PET, 0.773 for tau PET, and 0.708 for FDG PET). Relationships of plasma p-tau181 with brain pathologies were partly or entirely mediated by the corresponding CSF biomarkers. Besides, individuals with abnormal plasma p-tau181 level (>18.85 pg/ml) at baseline had a higher risk of pathological progression in brain amyloid (HR: 2.32, 95%CI 1.32–4.08) and FDG PET (3.21, 95%CI 2.06–5.01) status. Plasma p-tau181 may be a sensitive screening test for detecting brain pathologies, and serve as a predictive biomarker for Alzheimer’s pathophysiology.
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Zettergren, Anna, Jodie Lord, Nicholas J. Ashton, Andrea L. Benedet, Thomas K. Karikari, Juan Lantero Rodriguez, Anniina Snellman, et al. "Association between polygenic risk score of Alzheimer’s disease and plasma phosphorylated tau in individuals from the Alzheimer’s Disease Neuroimaging Initiative." Alzheimer's Research & Therapy 13, no. 1 (January 8, 2021). http://dx.doi.org/10.1186/s13195-020-00754-8.
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Abstract Background Recent studies suggest that plasma phosphorylated tau181 (p-tau181) is a highly specific biomarker for Alzheimer’s disease (AD)-related tau pathology. It has great potential for the diagnostic and prognostic evaluation of AD, since it identifies AD with the same accuracy as tau PET and CSF p-tau181 and predicts the development of AD dementia in cognitively unimpaired (CU) individuals and in those with mild cognitive impairment (MCI). Plasma p-tau181 may also be used as a biomarker in studies exploring disease pathogenesis, such as genetic or environmental risk factors for AD-type tau pathology. The aim of the present study was to investigate the relation between polygenic risk scores (PRSs) for AD and plasma p-tau181. Methods Data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) was used to examine the relation between AD PRSs, constructed based on findings in recent genome-wide association studies, and plasma p-tau181, using linear regression models. Analyses were performed in the total sample (n = 818), after stratification on diagnostic status (CU (n = 236), MCI (n = 434), AD dementia (n = 148)), and after stratification on Aβ pathology status (Aβ positives (n = 322), Aβ negatives (n = 409)). Results Associations between plasma p-tau181 and APOE PRSs (p = 3e−18–7e−15) and non-APOE PRSs (p = 3e−4–0.03) were seen in the total sample. The APOE PRSs were associated with plasma p-tau181 in all diagnostic groups (CU, MCI, and AD dementia), while the non-APOE PRSs were associated only in the MCI group. The APOE PRSs showed similar results in amyloid-β (Aβ)-positive and negative individuals (p = 5e−5–1e−3), while the non-APOE PRSs were associated with plasma p-tau181 in Aβ positives only (p = 0.02). Conclusions Polygenic risk for AD including APOE was found to associate with plasma p-tau181 independent of diagnostic and Aβ pathology status, while polygenic risk for AD beyond APOE was associated with plasma p-tau181 only in MCI and Aβ-positive individuals. These results extend the knowledge about the relation between genetic risk for AD and p-tau181, and further support the usefulness of plasma p-tau181 as a biomarker of AD.
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Zettergren, Anna, Jodie Lord, Nicholas J. Ashton, Andrea L. Benedet, Thomas K. Karikari, Juan Lantero Rodriguez, Anniina Snellman, et al. "Association between polygenic risk score of Alzheimer’s disease and plasma phosphorylated tau in individuals from the Alzheimer’s Disease Neuroimaging Initiative." Alzheimer's Research & Therapy 13, no. 1 (January 8, 2021). http://dx.doi.org/10.1186/s13195-020-00754-8.
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Abstract Background Recent studies suggest that plasma phosphorylated tau181 (p-tau181) is a highly specific biomarker for Alzheimer’s disease (AD)-related tau pathology. It has great potential for the diagnostic and prognostic evaluation of AD, since it identifies AD with the same accuracy as tau PET and CSF p-tau181 and predicts the development of AD dementia in cognitively unimpaired (CU) individuals and in those with mild cognitive impairment (MCI). Plasma p-tau181 may also be used as a biomarker in studies exploring disease pathogenesis, such as genetic or environmental risk factors for AD-type tau pathology. The aim of the present study was to investigate the relation between polygenic risk scores (PRSs) for AD and plasma p-tau181. Methods Data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) was used to examine the relation between AD PRSs, constructed based on findings in recent genome-wide association studies, and plasma p-tau181, using linear regression models. Analyses were performed in the total sample (n = 818), after stratification on diagnostic status (CU (n = 236), MCI (n = 434), AD dementia (n = 148)), and after stratification on Aβ pathology status (Aβ positives (n = 322), Aβ negatives (n = 409)). Results Associations between plasma p-tau181 and APOE PRSs (p = 3e−18–7e−15) and non-APOE PRSs (p = 3e−4–0.03) were seen in the total sample. The APOE PRSs were associated with plasma p-tau181 in all diagnostic groups (CU, MCI, and AD dementia), while the non-APOE PRSs were associated only in the MCI group. The APOE PRSs showed similar results in amyloid-β (Aβ)-positive and negative individuals (p = 5e−5–1e−3), while the non-APOE PRSs were associated with plasma p-tau181 in Aβ positives only (p = 0.02). Conclusions Polygenic risk for AD including APOE was found to associate with plasma p-tau181 independent of diagnostic and Aβ pathology status, while polygenic risk for AD beyond APOE was associated with plasma p-tau181 only in MCI and Aβ-positive individuals. These results extend the knowledge about the relation between genetic risk for AD and p-tau181, and further support the usefulness of plasma p-tau181 as a biomarker of AD.
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Lleó, Alberto, Henrik Zetterberg, Jordi Pegueroles, Thomas K. Karikari, María Carmona-Iragui, Nicholas J. Ashton, Victor Montal, et al. "Phosphorylated tau181 in plasma as a potential biomarker for Alzheimer’s disease in adults with Down syndrome." Nature Communications 12, no. 1 (July 14, 2021). http://dx.doi.org/10.1038/s41467-021-24319-x.
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AbstractPlasma tau phosphorylated at threonine 181 (p-tau181) predicts Alzheimer’s disease (AD) pathology with high accuracy in the general population. In this study, we investigated plasma p-tau181 as a biomarker of AD in individuals with Down syndrome (DS). We included 366 adults with DS (240 asymptomatic, 43 prodromal AD, 83 AD dementia) and 44 euploid cognitively normal controls. We measured plasma p-tau181 with a Single molecule array (Simoa) assay. We examined the diagnostic performance of p-tau181 for the detection of AD and the relationship with other fluid and imaging biomarkers. Plasma p-tau181 concentration showed an area under the curve of 0.80 [95% CI 0.73–0.87] and 0.92 [95% CI 0.89–0.95] for the discrimination between asymptomatic individuals versus those in the prodromal and dementia groups, respectively. Plasma p-tau181 correlated with atrophy and hypometabolism in temporoparietal regions. Our findings indicate that plasma p-tau181 concentration can be useful to detect AD in DS.
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Wang, Yan-Li, Jinglong Chen, Zhong-Li Du, Haoyi Weng, Yuan Zhang, Runzhi Li, Ziyan Jia, et al. "Plasma p-tau181 Level Predicts Neurodegeneration and Progression to Alzheimer's Dementia: A Longitudinal Study." Frontiers in Neurology 12 (September 7, 2021). http://dx.doi.org/10.3389/fneur.2021.695696.
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Background: Plasma-based biomarkers would be potential biomarkers for early diagnosis of Alzheimer's disease (AD) because they are more available and cost-effective than cerebrospinal fluid (CSF) or neuroimaging. Therefore, we aimed to evaluate whether phosphorylated tau181 (p-tau181) in plasma could be an accurate AD predictor.Methods: Participants from the ADNI database included 185 cognitively unimpaired subjects with negative Aβ (CU–), 66 subjects with pre-clinical AD (CU with positive Aβ), 164 subjects with mild cognitive impairment with negative Aβ (MCI–), 254 subjects with prodromal AD (MCI with positive Aβ), and 98 subjects with dementia. Multiple linear regression models, linear mixed-effects models, and local regression were used to explore cross-sectional and longitudinal associations of plasma p-tau181 with cognition, neuroimaging, or CSF biomarkers adjusted for age, sex, education, and APOE genotype. Besides, Kaplan–Meier and adjusted Cox-regression model were performed to predict the risk of progression to dementia. Receiver operating characteristic analyses were performed to evaluate the predictive value of p-tau181.Results: Plasma p-tau181 level was highest in AD dementia, followed by prodromal AD and pre-clinical AD. In pre-clinical AD, plasma p-tau181 was negatively associated with hippocampal volume (β = −0.031, p-value = 0.017). In prodromal AD, plasma p-tau181 was associated with decreased global cognition, executive function, memory, language, and visuospatial functioning (β range −0.119 to −0.273, p-value < 0.05) and correlated with hippocampal volume (β = −0.028, p-value < 0.005) and white matter hyperintensity volume (WMH) volume (β = 0.02, p-value = 0.01). In AD dementia, increased plasma p-tau181 was associated with worse memory. In the whole group, baseline plasma p-tau181 was significantly associated with longitudinal increases in multiple neuropsychological test z-scores and correlated with AD-related CSF biomarkers and hippocampal volume (p-value < 0.05). Meanwhile, CU or MCI with high plasma p-tau181 carried a higher risk of progression to dementia. The area under the curve (AUC) of the adjusted model (age, sex, education, APOE genotype, and plasma p-tau181) was 0.78; that of additionally included CSF biomarkers was 0.84.Conclusions: Plasma p-tau181 level is related to multiple AD-associated cognitive domains and AD-related CSF biomarkers at the clinical stages of AD. Moreover, plasma p-tau181 level is related to the change rates of cognitive decline and hippocampal atrophy. Thus, this study confirms the utility of plasma p-tau181 as a non-invasive biomarker for early detection and prediction of AD.
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Janelidze, Shorena, Erik Stomrud, Ruben Smith, Sebastian Palmqvist, Niklas Mattsson, David C. Airey, Nicholas K. Proctor, et al. "Cerebrospinal fluid p-tau217 performs better than p-tau181 as a biomarker of Alzheimer’s disease." Nature Communications 11, no. 1 (April 3, 2020). http://dx.doi.org/10.1038/s41467-020-15436-0.
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AbstractCerebrospinal fluid (CSF) p-tau181 (tau phosphorylated at threonine 181) is an established biomarker of Alzheimer’s disease (AD), reflecting abnormal tau metabolism in the brain. Here we investigate the performance of CSF p-tau217 as a biomarker of AD in comparison to p-tau181. In the Swedish BioFINDER cohort (n = 194), p-tau217 shows stronger correlations with the tau positron emission tomography (PET) tracer [18F]flortaucipir, and more accurately identifies individuals with abnormally increased [18F]flortaucipir retention. Furthermore, longitudinal increases in p-tau217 are higher compared to p-tau181 and better correlate with [18F]flortaucipir uptake. P-tau217 correlates better than p-tau181 with CSF and PET measures of neocortical amyloid-β burden and more accurately distinguishes AD dementia from non-AD neurodegenerative disorders. Higher correlations between p-tau217 and [18F]flortaucipir are corroborated in an independent EXPEDITION3 trial cohort (n = 32). The main results are validated using a different p-tau217 immunoassay. These findings suggest that p-tau217 might be more useful than p-tau181 in the diagnostic work up of AD.
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Therriault, Joseph, Andrea L. Benedet, Tharick A. Pascoal, Firoza Z. Lussier, Cecile Tissot, Thomas K. Karikari, Nicholas J. Ashton, et al. "Association of plasma P-tau181 with memory decline in non-demented adults." Brain Communications 3, no. 3 (June 14, 2021). http://dx.doi.org/10.1093/braincomms/fcab136.
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Abstract Alzheimer’s disease is the leading cause of dementia worldwide and is characterized by a long preclinical phase in which amyloid-β and tau accumulate in the absence of cognitive decline. In vivo biomarkers for Alzheimer’s disease are expensive, invasive and inaccessible, yet are critical for accurate disease diagnosis and patient management. Recent ultrasensitive methods to measure plasma phosphorylated tau 181 (p-tau181) display strong correlations with tau positron emission tomography, p-tau181 in CSF, and tau pathology at autopsy. The clinical utility of plasma-based p-tau181 biomarkers is unclear. In a longitudinal multicentre observational study, we assessed 1113 non-demented individuals (509 cognitively unimpaired elderly and 604 individuals with mild cognitive impairment) from the Alzheimer’s Disease Neuroimaging Initiative who underwent neuropsychological assessments and were evaluated for plasma p-tau181. The primary outcome was a memory composite z-score. Mixed-effect models assessed rates of memory decline in relation to baseline plasma p-tau181, and whether plasma p-tau181 significantly predicted memory decline beyond widely available clinical and genetic data (age, sex, years of education, cardiovascular and metabolic conditions, and APOEε4 status). Participants were followed for a median of 4.1 years. Baseline plasma p-tau181 was associated with lower baseline memory (β estimate: −0.49, standard error: 0.06, t-value: −7.97), as well as faster rates of memory decline (β estimate: −0.11, standard error: 0.01, t-value: −7.37). Moreover, the inclusion of plasma p-tau181 resulted in improved prediction of memory decline beyond clinical and genetic data (marginal R2 of 16.7–23%, χ2 = 100.81, P < 0.00001). Elevated baseline plasma p-tau181 was associated with higher rates of clinical progression to mild cognitive impairment (hazard ratio = 1.82, 95% confidence interval: 1.2–2.8) and from mild cognitive impairment to dementia (hazard ratio = 2.06, 95% confidence interval: 1.55–2.74). Our results suggest that in elderly individuals without dementia at baseline, plasma p-tau181 biomarkers were associated with greater memory decline and rates of clinical progression to dementia. Plasma p-tau181 improved prediction of memory decline above a model with currently available clinical and genetic data. While the clinical importance of this improvement in the prediction of memory decline is unknown, these results highlight the potential of plasma p-tau181 as a cost-effective and scalable Alzheimer’s disease biomarker.
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McGrath, Emer R., Alexa S. Beiser, Adrienne O’Donnell, Qiong Yang, Saptaparni Ghosh, Mitzi M. Gonzales, Jayandra J. Himali, et al. "Blood Phosphorylated Tau 181 as a Biomarker for Amyloid Burden on Brain PET in Cognitively Healthy Adults." Journal of Alzheimer's Disease, April 25, 2022, 1–10. http://dx.doi.org/10.3233/jad-215639.
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Background: Plasma phosphorylated-tau181 (p-tau181) is a promising biomarker for Alzheimer’s disease (AD) and may offer utility for predicting preclinical disease. Objective: To evaluate the prospective association between plasma p-tau181 and amyloid-β (Aβ) and tau-PET deposition in cognitively unimpaired individuals. Methods: Plasma p-tau181 levels were measured at baseline in 52 [48% women, mean 64.4 (SD 5.5) years] cognitively unimpaired Framingham Offspring cohort participants using samples stored between 2011–2014 who subsequently underwent 11C-Pittsburgh Compound-B (PiB)-PET and/or 18F-Flortaucipir (FTP)-PET scans (n = 18 with tau-PET) a mean of 6.8 (SD 0.6) years later. Our primary outcomes included Aβ-precuneus, Aβ-FLR (frontal, lateral, and retrosplenial cortices) and tau-global composite region PET deposition. Secondary outcomes included individual regional Aβ and tau PET-deposition. P-tau181 was compared with plasma neurofilament light chain (NFL) and glial fibrillary acidic protein (GFAP) in predicting PET outcomes. Results: P-tau181 was associated with increased Aβ deposition in the FLR (β±SE, 1.25±0.30, p < 0.0001), precuneus (1.35±0.29, p < 0.001), and other cortical regions. Plasma NFL (1.30±0.49, p = 0.01) and GFAP (1.46±0.39, p < 0.001) were also associated with FLR Aβ deposition. In models including all three biomarkers adjusted for age, sex, APOE E4 allele, AD polygenic risk score and cortical atrophy score, p-tau181 (0.93±0.31, p < 0.01, R2 = 0.18) and GFAP (0.93±0.41, p = 0.03, R2 = 0.11), but not NFL (0.25±0.51, p = 0.62, R2 = 0.01), were associated with FLR-Aβ deposition. Plasma p-tau181 was not associated with tau-PET burden. Conclusion: In cognitively unimpaired adults, elevated plasma p-tau181 is associated with future increased Aβ deposition across multiple brain regions. Our results highlight the potential utility of p-tau181 as a blood-biomarker to screen for brain-amyloid deposition in cognitively healthy individuals in a community-setting.
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McGrath, Emer R., Alexa S. Beiser, Adrienne O’Donnell, Qiong Yang, Saptaparni Ghosh, Mitzi M. Gonzales, Jayandra J. Himali, et al. "Blood Phosphorylated Tau 181 as a Biomarker for Amyloid Burden on Brain PET in Cognitively Healthy Adults." Journal of Alzheimer's Disease, April 25, 2022, 1–10. http://dx.doi.org/10.3233/jad-215639.
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Background: Plasma phosphorylated-tau181 (p-tau181) is a promising biomarker for Alzheimer’s disease (AD) and may offer utility for predicting preclinical disease. Objective: To evaluate the prospective association between plasma p-tau181 and amyloid-β (Aβ) and tau-PET deposition in cognitively unimpaired individuals. Methods: Plasma p-tau181 levels were measured at baseline in 52 [48% women, mean 64.4 (SD 5.5) years] cognitively unimpaired Framingham Offspring cohort participants using samples stored between 2011–2014 who subsequently underwent 11C-Pittsburgh Compound-B (PiB)-PET and/or 18F-Flortaucipir (FTP)-PET scans (n = 18 with tau-PET) a mean of 6.8 (SD 0.6) years later. Our primary outcomes included Aβ-precuneus, Aβ-FLR (frontal, lateral, and retrosplenial cortices) and tau-global composite region PET deposition. Secondary outcomes included individual regional Aβ and tau PET-deposition. P-tau181 was compared with plasma neurofilament light chain (NFL) and glial fibrillary acidic protein (GFAP) in predicting PET outcomes. Results: P-tau181 was associated with increased Aβ deposition in the FLR (β±SE, 1.25±0.30, p < 0.0001), precuneus (1.35±0.29, p < 0.001), and other cortical regions. Plasma NFL (1.30±0.49, p = 0.01) and GFAP (1.46±0.39, p < 0.001) were also associated with FLR Aβ deposition. In models including all three biomarkers adjusted for age, sex, APOE E4 allele, AD polygenic risk score and cortical atrophy score, p-tau181 (0.93±0.31, p < 0.01, R2 = 0.18) and GFAP (0.93±0.41, p = 0.03, R2 = 0.11), but not NFL (0.25±0.51, p = 0.62, R2 = 0.01), were associated with FLR-Aβ deposition. Plasma p-tau181 was not associated with tau-PET burden. Conclusion: In cognitively unimpaired adults, elevated plasma p-tau181 is associated with future increased Aβ deposition across multiple brain regions. Our results highlight the potential utility of p-tau181 as a blood-biomarker to screen for brain-amyloid deposition in cognitively healthy individuals in a community-setting.
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Moscoso, Alexis, Michel J. Grothe, Nicholas J. Ashton, Thomas K. Karikari, Juan Lantero Rodriguez, Anniina Snellman, Marc Suárez-Calvet, Henrik Zetterberg, Kaj Blennow, and Michael Schöll. "Time course of phosphorylated-tau181 in blood across the Alzheimer’s disease spectrum." Brain, November 30, 2020. http://dx.doi.org/10.1093/brain/awaa399.
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Abstract Tau phosphorylated at threonine 181 (p-tau181) measured in blood plasma has recently been proposed as an accessible, scalable, and highly specific biomarker for Alzheimer’s disease. Longitudinal studies, however, investigating the temporal dynamics of this novel biomarker are lacking. It is therefore unclear when in the disease process plasma p-tau181 increases above physiological levels and how it relates to the spatiotemporal progression of Alzheimer’s disease characteristic pathologies. We aimed to establish the natural time course of plasma p-tau181 across the sporadic Alzheimer’s disease spectrum in comparison to those of established imaging and fluid-derived biomarkers of Alzheimer’s disease. We examined longitudinal data from a large prospective cohort of elderly individuals enrolled in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) (n = 1067) covering a wide clinical spectrum from normal cognition to dementia, and with measures of plasma p-tau181 and an 18F-florbetapir amyloid-β PET scan at baseline. A subset of participants (n = 864) also had measures of amyloid-β1–42 and p-tau181 levels in CSF, and another subset (n = 298) had undergone an 18F-flortaucipir tau PET scan 6 years later. We performed brain-wide analyses to investigate the associations of plasma p-tau181 baseline levels and longitudinal change with progression of regional amyloid-β pathology and tau burden 6 years later, and estimated the time course of changes in plasma p-tau181 and other Alzheimer’s disease biomarkers using a previously developed method for the construction of long-term biomarker temporal trajectories using shorter-term longitudinal data. Smoothing splines demonstrated that earliest plasma p-tau181 changes occurred even before amyloid-β markers reached abnormal levels, with greater rates of change correlating with increased amyloid-β pathology. Voxel-wise PET analyses yielded relatively weak, yet significant, associations of plasma p-tau181 with amyloid-β pathology in early accumulating brain regions in cognitively healthy individuals, while the strongest associations with amyloid-β were observed in late accumulating regions in patients with mild cognitive impairment. Cross-sectional and particularly longitudinal measures of plasma p-tau181 were associated with widespread cortical tau aggregation 6 years later, covering temporoparietal regions typical for neurofibrillary tangle distribution in Alzheimer’s disease. Finally, we estimated that plasma p-tau181 reaches abnormal levels ∼6.5 and 5.7 years after CSF and PET measures of amyloid-β, respectively, following similar dynamics as CSF p-tau181. Our findings suggest that plasma p-tau181 increases are associated with the presence of widespread cortical amyloid-β pathology and with prospective Alzheimer’s disease typical tau aggregation, providing clear implications for the use of this novel blood biomarker as a diagnostic and screening tool for Alzheimer’s disease.
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Asken, Breton M., Jeremy A. Tanner, Lawren VandeVrede, William G. Mantyh, Kaitlin B. Casaletto, Adam M. Staffaroni, Renaud La Joie, et al. "Plasma P-tau181 and P-tau217 in Patients With Traumatic Encephalopathy Syndrome With and Without Evidence of Alzheimer Disease Pathology." Neurology, May 16, 2022, 10.1212/WNL.0000000000200678. http://dx.doi.org/10.1212/wnl.0000000000200678.
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Background:Traumatic encephalopathy syndrome (TES) has overlapping clinical symptoms with Alzheimer’s disease (AD). AD pathology commonly co-occurs with chronic traumatic encephalopathy (CTE) pathology. There are currently no validated CTE biomarkers. AD-specific biomarkers like plasma P-tau181 and P-tau217 may help to identify TES patients who have AD pathology.Methods:We measured plasma P-tau181 and P-tau217 (Meso Scale Discovery electrochemiluminescence) in patients with TES, MCI/dementia with biomarker-confirmed AD (“AD”), and healthy controls (“HC”). Patients underwent Aβ-PET and a subset underwent tau-PET using [18F]Flortaucipir. We compared plasma P-Tau levels controlling for age and sex and also used AUC analyses to evaluate accuracy of group differentiation. In TES patients, we evaluated associations between plasma P-Tau, years of repetitive head impact exposure, and tau-PET. Four TES patients with autopsy-confirmed CTE were described qualitatively.Results:The sample included 131 participants (TES, N=18; AD, N=65; HC, N=48). Aβ(+) TES patients (N=10), but not Aβ(-) TES, had significantly higher plasma P-Tau levels than HC (P-tau181: p<.001; d=1.34; P-tau217: p<.001; d=1.59). There was a trend for Aβ(+) TES having higher plasma P-Tau than Aβ(-) TES (P-tau181: p=.06, d=1.06; P-tau217: p=.09, d=0.93). AUC analyses showed good classification of Aβ(+) TES from HC for P-tau181 (AUC=0.87 [0.71-1.00]) and P-tau217 (AUC=0.93 [0.86-1.00]). Plasma P-tau217 showed fair differentiation of Aβ(+) TES from Aβ(-) TES (AUC=0.79 [0.54-1.00], p=.04), while classification accuracy of P-tau181 was slightly lower and not statistically significant (AUC=0.71 [0.46-0.96], p=.13). AD patients had higher tau-PET tracer uptake than Aβ(+) TES and were well differentiated using P-tau181 (AUC=0.81 [0.68-0.94]) and P-tau217 (AUC=0.86 [0.73-0.98]). Plasma P-Tau correlated with tau-PET signal in Aβ(+) TES but not in Aβ(-) TES, and there was no association between plasma P-Tau and years of repetitive head impact exposure. TES patients with severe CTE and no AD at autopsy had low P-tau181 and P-tau217 levels.Discussion:Measuring P-tau181 and P-tau217 in plasma may be a feasible and scalable fluid biomarker for identifying AD pathology in TES. Low plasma P-Tau levels may be used to increase clinical suspicion of CTE over AD as a primary pathology in TES. There currently is no support for P-tau181 or P-tau217 as in vivo biomarkers of CTE tau. Larger studies of patients with pathologically confirmed CTE are needed.Classification of Evidence:This study provides Class III evidence that (1) among patients with TES and abnormal Aβ-PET scans, elevated plasma P-tau can differentiate between affected individuals and healthy controls; (2) low plasma P-tau may help identify TES patients who do not have Alzheimer's and (3) plasma P-tau181 and P-tau 217 are not useful biomarkers of TES patients who do not have Alzheimer's disease.
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Chen, Shi-Dong, Yu-Yuan Huang, Xue-Ning Shen, Yu Guo, Lan Tan, Qiang Dong, and Jin-Tai Yu. "Longitudinal plasma phosphorylated tau 181 tracks disease progression in Alzheimer’s disease." Translational Psychiatry 11, no. 1 (June 2021). http://dx.doi.org/10.1038/s41398-021-01476-7.
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AbstractTo assess plasma phosphorylated tau181 (p-tau181) as a progression biomarker in Alzheimer’s disease (AD), we examined longitudinal plasma p-tau181 of 1184 participants (403 cognitively normal (CN), 560 patients with mild cognitive impairment (MCI), and 221 with AD dementia) from Alzheimer’s Disease Neuroimaging Initiative (ADNI). The plasma p-tau level was increased at baseline for MCI and AD dementia (mean: CN, 15.4 pg/mL; MCI, 18.4 pg/mL; AD dementia, 23.7 pg/mL; P < 0.001) and increased significantly over time at preclinical (Aβ-positive CN), prodromal (Aβ-positive MCI), and dementia (Aβ-positive dementia) stage of AD. A longitudinal increase of plasma p-tau181 was associated with abnormal cerebrospinal fluid biomarker levels (low Aβ42, high phosphorylated tau, and high total tau, all P < 0.001), amyloid accumulation (P < 0.001) and hypometabolism (P = 0.002) on positron emission tomography, atrophy in structure imaging (small hippocampal (P = 0.030), middle temporal (P = 0.008), and whole brain (P = 0.027) volume, and large ventricular volume (P = 0.008)), and deteriorated cognitive performance (global cognition and memory, language, executive function, and visuospatial function, all P < 0.050) at baseline. Furthermore, longitudinal plasma p-tau181 correlated with concurrent changes of nearly all these AD-related hallmarks and faster increase in plasma p-tau181 correlated with faster worsening cognition in all diagnostic groups. Importantly, most associations remained significant in Aβ-positive group and became non-significant in Aβ-negative group. Longitudinal analyses of plasma p-tau181 suggest its potential as a noninvasive biomarker to track disease progression in AD and to monitor effects of disease-modifying therapeutics in clinical trials.
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Grothe, Michel J., Alexis Moscoso, Nicholas J. Ashton, Thomas K. Karikari, Juan Lantero-Rodriguez, Anniina Snellman, Henrik Zetterberg, Kaj Blennow, and Michael Schöll. "Associations of Fully Automated CSF and Novel Plasma Biomarkers With Alzheimer Disease Neuropathology at Autopsy." Neurology, July 15, 2021, 10.1212/WNL.0000000000012513. http://dx.doi.org/10.1212/wnl.0000000000012513.
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Objective:To study cerebrospinal fluid (CSF) biomarkers of Alzheimer’s disease (AD) analyzed by fully automated Elecsys immunoassays in comparison to neuropathologic gold standards, and compare their accuracy to plasma phosphorylated tau (p-tau181) measured using a novel Simoa method.Methods:We studied ante-mortem Elecsys-derived CSF biomarkers in 45 individuals who underwent standardized post-mortem assessments of AD and non-AD neuropathologic changes at autopsy. In a subset of 26 participants, we also analysed ante-mortem levels of plasma p-tau181 and neurofilament light (NfL). Reference biomarker values were obtained from 146 amyloid-PET-negative healthy controls (HC).Results:All CSF biomarkers clearly distinguished pathology-confirmed AD dementia (N=27) from HC (AUCs=0.86-1.00). CSF total-tau (t-tau), p-tau181, and their ratios with Aβ1-42, also accurately distinguished pathology-confirmed AD from non-AD dementia (N=8; AUCs=0.94-0.97). In pathology-specific analyses, intermediate-to-high Thal amyloid phases were best detected by CSF Aβ1-42 (AUC[95% CI]=0.91[0.81-1]), while intermediate-to-high CERAD neuritic plaques and Braak tau stages were best detected by CSF p-tau181 (AUC=0.89[0.79-0.99] and 0.88[0.77-0.99], respectively). Optimal Elecsys biomarker cut-offs were derived at 1097/229/19 pg/ml for Aβ1-42, t-tau, and p-tau181. In the plasma subsample, both plasma p-tau181 (AUC=0.91[0.86-0.96]) and NfL (AUC=0.93[0.87-0.99]) accurately distinguished pathology-confirmed AD (N=14) from HC. However, only p-tau181 distinguished AD from non-AD dementia cases (N=4; AUC=0.96[0.88-1.00]), and showed a similar, though weaker, pathologic specificity for neuritic plaques (AUC=0.75[0.52-0.98]) and Braak stage (AUC=0.71[0.44-0.98]) as CSF p-tau181.Conclusions:Elecsys-derived CSF biomarkers detect AD neuropathologic changes with very high discriminative accuracy in-vivo. Preliminary findings support the use of plasma p-tau181 as an easily accessible and scalable biomarker of AD pathology.Classification of Evidence:This study provides Class II evidence that fully-automated CSF t-tau and p-tau181measurements discriminate between autopsy-confirmed Alzheimer's disease and other dementias.
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Baiardi, Simone, Corinne Quadalti, Angela Mammana, Sofia Dellavalle, Corrado Zenesini, Luisa Sambati, Roberta Pantieri, et al. "Diagnostic value of plasma p-tau181, NfL, and GFAP in a clinical setting cohort of prevalent neurodegenerative dementias." Alzheimer's Research & Therapy 14, no. 1 (October 12, 2022). http://dx.doi.org/10.1186/s13195-022-01093-6.
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Abstract Background Increasing evidence supports the use of plasma biomarkers of neurodegeneration and neuroinflammation to screen and diagnose patients with dementia. However, confirmatory studies are required to demonstrate their usefulness in the clinical setting. Methods We evaluated plasma and cerebrospinal fluid (CSF) samples from consecutive patients with frontotemporal dementia (FTD) (n = 59), progressive supranuclear palsy (PSP) (n = 31), corticobasal syndrome (CBS) (n = 29), dementia with Lewy bodies (DLB) (n = 49), Alzheimer disease (AD) (n = 97), and suspected non-AD physiopathology (n = 51), as well as plasma samples from 60 healthy controls (HC). We measured neurofilament light chain (NfL), phospho-tau181 (p-tau181), and glial fibrillary acid protein (GFAP) using Simoa (all plasma biomarkers and CSF GFAP), CLEIA (CSF p-tau181), and ELISA (CSF NfL) assays. Additionally, we stratified patients according to the A/T/N classification scheme and the CSF α-synuclein real-time quaking-induced conversion assay (RT-QuIC) results. Results We found good correlations between CSF and plasma biomarkers for NfL (rho = 0.668, p < 0.001) and p-tau181 (rho = 0.619, p < 0.001). Plasma NfL was significantly higher in disease groups than in HC and showed a greater increase in FTD than in AD [44.9 (28.1–68.6) vs. 21.9 (17.0–27.9) pg/ml, p < 0.001]. Conversely, plasma p-tau181 and GFAP levels were significantly higher in AD than in FTD [3.2 (2.4–4.3) vs. 1.1 (0.7–1.6) pg/ml, p < 0.001; 404.7 (279.7–503.0) vs. 198.2 (143.9–316.8) pg/ml, p < 0.001]. GFAP also allowed discriminating disease groups from HC. In the distinction between FTD and AD, plasma p-tau181 showed better accuracy (AUC 0.964) than NfL (AUC 0.791) and GFAP (AUC 0.818). In DLB and CBS, CSF amyloid positive (A+) subjects had higher plasma p-tau181 and GFAP levels than A− individuals. CSF RT-QuIC showed positive α-synuclein seeding activity in 96% DLB and 15% AD patients with no differences in plasma biomarker levels in those stratified by RT-QuIC result. Conclusions In a single-center clinical cohort, we confirm the high diagnostic value of plasma p-tau181 for distinguishing FTD from AD and plasma NfL for discriminating degenerative dementias from HC. Plasma GFAP alone differentiates AD from FTD and neurodegenerative dementias from HC but with lower accuracy than p-tau181 and NfL. In CBS and DLB, plasma p-tau181 and GFAP levels are significantly influenced by beta-amyloid pathology.
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Pilotto, Andrea, Marta Parigi, Giulio Bonzi, Beatrice Battaglio, Elisabetta Ferrari, Lorenza Mensi, Alberto Benussi, et al. "Differences Between Plasma and Cerebrospinal Fluid p-tau181 and p-tau231 in Early Alzheimer’s Disease." Journal of Alzheimer's Disease, April 5, 2022, 1–7. http://dx.doi.org/10.3233/jad-215646.
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Plasma phosphorylated tau species have been recently proposed as peripheral markers of Alzheimer’s disease (AD) pathology. In this cross-sectional study including 91 subjects, plasma and cerebrospinal fluid (CSF) p-tau181 and p-tau231 levels were elevated in the early symptomatic stages of AD. Plasma p-tau231 and p-tau181 were strongly related to CSF phosphorylated tau, total tau and amyloid and exhibited a high accuracy—close to CSF p-tau231 and p-tau181—to identify AD already in the early stage of the disease. The findings might support the use as diagnostic and prognostic peripheral AD biomarkers in both research and clinical settings.
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Sarto, Jordi, Raquel Ruiz-García, Núria Guillén, Óscar Ramos-Campoy, Neus Falgàs, Diana Esteller, José Contador, et al. "Diagnostic Performance and Clinical Applicability of Blood-Based Biomarkers in a Prospective Memory Clinic Cohort." Neurology, November 30, 2022, 10.1212/WNL.0000000000201597. http://dx.doi.org/10.1212/wnl.0000000000201597.
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Background and Objectives:Blood-based biomarkers have emerged as minimally-invasive options for evaluating cognitive impairment. Most studies to date have assessed them in research cohorts, limiting their generalization to everyday clinical practice. We evaluated their diagnostic performance and clinical applicability in a prospective, real-world, memory clinic cohort.Methods:All patients referred with suspected cognitive impairment between July 2019 and June 2021, were prospectively invited to participate. Five plasma biomarkers (p-tau181, GFAP, NfL, t-tau, UCH-L1) were determined with SiMoA. Performance was assessed in comparison to clinical diagnosis (blinded to plasma results) and amyloid status (CSF/PET). A group of cognitively unimpaired (CU) controls was also included.Results:Three hundred forty-nine participants (mean age 68, SD 8.3 years) and 36 CU controls (mean age 61.7, SD 8.2 years) were included. In the sub-cohort with available AD biomarkers (n=268), plasma p-tau181 and GFAP had a high diagnostic accuracy to differentiate AD from non-neurodegenerative causes (AUC 0.94 and 0.92, respectively), with p-tau181 systematically outperforming GFAP. Plasma p-tau181 levels predicted amyloid status (85% sensitivity and specificity) with accurate individual prediction in approximately 60% of the subjects. Plasma NfL differentiated frontotemporal dementia syndromes (FTD) from CU (0.90) and non-neurodegenerative causes (0.93), while the discriminative capacity with AD and between all neurodegenerative and non-neurodegenerative causes was less accurate. A combination of p-tau181 and NfL identified FTD with 82% sensitivity and 85% specificity and had a negative predictive value for neurodegenerative diagnosis of 86%, ruling out half of the non-neurodegenerative diagnoses. In the sub-cohort without AD biomarkers similar results were obtained. T-tau and UCH-L1 did not offer added diagnostic value.Discussion:Plasma p-tau181 predicted amyloid status with high accuracy and could have potentially avoided CSF/amyloid PET testing in approximately 60% of subjects in a memory-clinic setting. NfL was useful for identifying FTD from non-neurodegenerative causes but behaved worse than p-tau181 in all other comparisons. Combining p-tau181 and NfL improved diagnostic performance for FTD and non-neurodegenerative diagnoses. However, the 14% false-negative results suggest that further improvement is needed before implementation outside memory clinics.Classification of Evidence:This study provides Class I evidence that plasma p-tau181 correlates with the presence or absence of AD and a combination of plasma p-tau181 and NfL correlate moderately well with a diagnosis of FTD.
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Morrison, Madeline S., Hugo J. Aparicio, Kaj Blennow, Henrik Zetterberg, Nicholas J. Ashton, Thomas K. Karikari, Yorghos Tripodis, et al. "Antemortem plasma phosphorylated tau (181) predicts Alzheimer’s disease neuropathology and regional tau at autopsy." Brain, May 13, 2022. http://dx.doi.org/10.1093/brain/awac175.
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Abstract Blood-based biomarkers such as tau phosphorylated at threonine 181 (phosphorylated-tau181) represent an accessible, cost-effective, and scalable approach for the in vivo detection of Alzheimer’s disease pathophysiology. Plasma-pathological correlation studies are needed to validate plasma phosphorylated-tau181 as an accurate and reliable biomarker of Alzheimer’s disease neuropathologic changes. This plasma-to-autopsy correlation study included participants from the Boston University Alzheimer’s Disease Research Center who had a plasma sample analyzed for phosphorylated-tau181 between 2008-2018 and donated their brain for neuropathological examination. Plasma phosphorelated-tau181 was measured with single molecule array technology. Of 103 participants, 62 (60.2%) had autopsy-confirmed Alzheimer’s disease. Average time between blood draw and death was 5.6 years (SD = 3.1 years). Multivariable analyses showed higher plasma phosphorylated-tau181 concentrations were associated with increased odds for having autopsy-confirmed Alzheimer’s disease (AUC = 0.82, OR = 1.07, 95% CI = 1.03-1.11, p < 0.01; phosphorylated-tau standardized [z-transformed]: OR = 2.98, 95% CI = 1.50-5.93, p < 0.01). Higher plasma phosphorylated-tau181 levels were associated with increased odds for having a higher Braak stage (OR = 1.06, 95% CI = 1.02-1.09, p < 0.001) and more severe phosphorylated-tau across six cortical and subcortical brain regions (ORs = 1.03-1.06, p < 0.05). The association between plasma phosphorylated-tau181 and Alzheimer’s disease was strongest in those who were demented at time of blood draw (OR = 1.25, 95%CI = 1.02-1.53), but an effect existed among the non-demented (OR = 1.05, 95% CI = 1.01-1.10). There was higher discrimination accuracy for Alzheimer’s disease when blood draw occurred in years closer to death, however, higher plasma phosphorylated-tau181 levels were associated with Alzheimer’s disease even when blood draw occurred >5 years from death. Antemortem plasma phosphorylated-tau181 concentrations were associated with Alzheimer’s disease neuropathology and accurately differentiated brain donors with and without autopsy-confirmed Alzheimer’s disease. These findings support plasma phosphorylated-tau181 as a scalable biomarker for the detection of Alzheimer’s disease.
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Leuzy, Antoine, Shorena Janelidze, Niklas Mattsson-Carlgren, Sebastian Palmqvist, Dirk Jacobs, Claudia Cicognola, Erik Stomrud, Eugeen Vanmechelen, Jeffrey L. Dage, and Oskar Hansson. "Comparing the Clinical Utility and Diagnostic Performance of Cerebrospinal Fluid P-Tau181, P-Tau217 and P-Tau231 Assays." Neurology, September 7, 2021, 10.1212/WNL.0000000000012727. http://dx.doi.org/10.1212/wnl.0000000000012727.
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Background and Objectives:Phosphorylated tau (P-tau) in cerebrospinal fluid (CSF) is considered an important biomarker in Alzheimer’s disease (AD) and has been incorporated in recent diagnostic criteria. Several variants exist, including P-tau at threonines 181 (P-tau181), 217 (P-tau217) and 231 (P-tau231). However, no studies have compared their diagnostic performance or association to amyloid-β (Aβ) and Tau positron emission tomography (PET). Understanding which P-tau variant to use remains an important yet answered question. We aimed to compare the diagnostic accuracy of P-tau181, P-tau217 and P-tau231 in CSF for AD and their association with Aβ and Tau-PET.Methods:629 subjects from the Swedish BioFINDER-2 study were included (cognitively unimpaired, n=334; Aβ-positive mild cognitive impairment, n=84; AD dementia, n=119; and non-AD disorders, n=92). In addition to P-tau181 and P-tau217 measured using assays with the same detector antibodies from Eli Lilly (P-tau181Lilly, P-tau217Lilly) and P-tau231, we also included P-tau181 measurements from two commonly used assays (Innotest and Elecsys).Results:Though all P-tau variants increased across the AD continuum, P-tau217Lilly showed the greatest dynamic range (13-fold-increase vs 1.9-5.4-fold-increase for other P-tau variants for AD dementia vs non-AD). P-tau217Lilly showed stronger correlations with Aβ- and Tau-PET (P<0.0001). P-tau217Lilly exhibited higher accuracy than other P-tau variants for separating AD dementia from non-AD (AUC, 0.991vs 0.906-0.982, P<0.0001) and for identifying Aβ- (AUC, 0.951 vs 0.816-0.924, P<0.0001) and Tau-PET positivity (AUC, 0.957 vs 0.836-0.938, P<0.0001). Finally, P-tau181Lilly generally performed better than the other P-tau181 assays, (e.g., AD dementia vs non-AD, AUC, 0.976 vs 0.923, P<0.0001).Discussion:CSF P-tau217Lilly seem to be more useful than other included P-tau assays in the work-up of AD. Varied results across P-tau181 assays also highlights the importance of anti-tau antibodies for biomarker performance.Classification of evidence:This study provides class II evidence that phosphorylated tau at threonine 217 provides higher diagnostic accuracy for diagnosis of AD dementia than P-tau at threonine 181 or 231.
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Batzu, Lucia, Silvia Rota, Abdul Hye, Amanda Heslegrave, Dhaval Trivedi, Lucy L. Gibson, Chloe Farrell, et al. "Plasma p-tau181, neurofilament light chain and association with cognition in Parkinson’s disease." npj Parkinson's Disease 8, no. 1 (November 12, 2022). http://dx.doi.org/10.1038/s41531-022-00384-x.
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AbstractEarly identification of cognitive impairment in Parkinson’s disease (PD) has important clinical and research implications. The aim of our study was to investigate the role of plasma tau phosphorylated at amino acid 181 (p-tau181) and plasma neurofilament light chain (NfL) as biomarkers of cognition in PD. Baseline concentrations of plasma p-tau181 and NfL were measured in a cohort of 136 patients with PD and 63 healthy controls (HC). Forty-seven PD patients were followed up for up to 2 years. Cross-sectional and longitudinal associations between baseline plasma biomarkers and cognitive progression were investigated using linear regression and linear mixed effects models. At baseline, plasma p-tau181 concentration was significantly higher in PD subjects compared with HC (p = 0.026). In PD patients, higher plasma NfL was associated with lower MMSE score at baseline, after adjusting for age, sex and education (p = 0.027). Baseline plasma NfL also predicted MMSE decline over time in the PD group (p = 0.020). No significant association between plasma p-tau181 concentration and baseline or longitudinal cognitive performance was found. While the role of p-tau181 as a diagnostic biomarker for PD and its relationship with cognition need further elucidation, plasma NfL may serve as a feasible, non-invasive biomarker of cognitive progression in PD.
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Wilson, Edward N., Christina B. Young, Javier Ramos Benitez, Michelle S. Swarovski, Igor Feinstein, Manu Vandijck, Yann Le Guen, et al. "Performance of a fully-automated Lumipulse plasma phospho-tau181 assay for Alzheimer’s disease." Alzheimer's Research & Therapy 14, no. 1 (November 12, 2022). http://dx.doi.org/10.1186/s13195-022-01116-2.
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Abstract Background The recent promise of disease-modifying therapies for Alzheimer’s disease (AD) has reinforced the need for accurate biomarkers for early disease detection, diagnosis and treatment monitoring. Advances in the development of novel blood-based biomarkers for AD have revealed that plasma levels of tau phosphorylated at various residues are specific and sensitive to AD dementia. However, the currently available tests have shortcomings in access, throughput, and scalability that limit widespread implementation. Methods We evaluated the diagnostic and prognostic performance of a high-throughput and fully-automated Lumipulse plasma p-tau181 assay for the detection of AD. Plasma from older clinically unimpaired individuals (CU, n = 463) and patients with mild cognitive impairment (MCI, n = 107) or AD dementia (n = 78) were obtained from the longitudinal Stanford University Alzheimer’s Disease Research Center (ADRC) and the Stanford Aging and Memory Study (SAMS) cohorts. We evaluated the discriminative accuracy of plasma p-tau181 for clinical AD diagnosis, association with amyloid β peptides and p-tau181 concentrations in CSF, association with amyloid positron emission tomography (PET), and ability to predict longitudinal cognitive and functional change. Results The assay showed robust performance in differentiating AD from control participants (AUC 0.959, CI: 0.912 to 0.990), and was strongly associated with CSF p-tau181, CSF Aβ42/Aβ40 ratio, and amyloid-PET global SUVRs. Associations between plasma p-tau181 with CSF biomarkers were significant when examined separately in Aβ+ and Aβ− groups. Plasma p-tau181 significantly increased over time in CU and AD diagnostic groups. After controlling for clinical diagnosis, age, sex, and education, baseline plasma p-tau181 predicted change in MoCA overall and change in CDR Sum of Boxes in the AD group over follow-up of up to 5 years. Conclusions This fully-automated and available blood-based biomarker assay therefore may be useful for early detection, diagnosis, prognosis, and treatment monitoring of AD.
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Xiao, Zhenxu, Xue Wu, Wanqing Wu, Jingwei Yi, Xiaoniu Liang, Saineng Ding, Li Zheng, et al. "Plasma biomarker profiles and the correlation with cognitive function across the clinical spectrum of Alzheimer’s disease." Alzheimer's Research & Therapy 13, no. 1 (July 5, 2021). http://dx.doi.org/10.1186/s13195-021-00864-x.
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Abstract Background Plasma biomarkers showed a promising value in the disease diagnosis and management of Alzheimer’s disease (AD). However, profiles of the biomarkers and the associations with cognition across a spectrum of cognitive stages have seldom been reported. Methods We recruited 320 individuals with cognitive impairment and 131 cognitively normal participants from a memory clinic and a community cohort. Participants were classified into 6 groups based on their Clinical Dementia Rating (CDR) scores and clinical diagnosis, including AD, amnestic mild cognitive impairment (aMCI), and normal cognition (NC). A battery of neuropsychological tests was used to assess the global and domain-specific cognition. Plasma Aβ1-40, Aβ1-42, Aβ1-42/Aβ1-40, total tau (t-tau), neurofilament protein light chain (NfL), and phosphorylated tau at threonine 181 (p-tau181) were quantified using the single-molecule array (Simoa) platform. Results All the plasma markers (Aβ1-40, Aβ1-42, Aβ1-42/Aβ1-40, t-tau, NfL, p-tau181) showed certain discrepancies among NC, aMCI, and AD groups. The p-tau181 level showed a continuous escalating trend as the CDR scores increased from 0 (NC group) to 3 (severe AD). Compared with other biomarkers, p-tau181 had correlations with broader cognitive domains, covering global cognition (r = −0.536, P < 0.0001), memory (r = −0.481, P < 0.0001), attention (r = −0.437, P < 0.0001), visuospatial function (r = −0.385, P < 0.0001), and language (r = −0.177, P = 0.0003). Among participants with CDR ≥ 1, higher p-tau181 was correlated with worse global cognition (r = −0.301, P < 0.001). Conclusions Plasma p-tau181 had correlations with broader cognitive domains, suggesting its potential as a promising clinical-relevant blood-based biomarker.
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Bayoumy, Sherif, Inge M. W. Verberk, Ben den Dulk, Zulaiga Hussainali, Marissa Zwan, Wiesje M. van der Flier, Nicholas J. Ashton, et al. "Clinical and analytical comparison of six Simoa assays for plasma P-tau isoforms P-tau181, P-tau217, and P-tau231." Alzheimer's Research & Therapy 13, no. 1 (December 2021). http://dx.doi.org/10.1186/s13195-021-00939-9.
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Abstract Introduction Studies using different assays and technologies showed highly promising diagnostic value of plasma phosphorylated (P-)tau levels for Alzheimer’s disease (AD). We aimed to compare six P-tau Simoa assays, including three P-tau181 (Eli Lilly, ADx, Quanterix), one P-tau217 (Eli Lilly), and two P-tau231 (ADx, Gothenburg). Methods We studied the analytical (sensitivity, precision, parallelism, dilution linearity, and recovery) and clinical (40 AD dementia patients, age 66±8years, 50%F; 40 age- and sex-matched controls) performance of the assays. Results All assays showed robust analytical performance, and particularly P-tau217 Eli Lilly; P-tau231 Gothenburg and all P-tau181 assays showed robust clinical performance to differentiate AD from controls, with AUCs 0.936–0.995 (P-tau231 ADx: AUC = 0.719). Results obtained with all P-tau181 assays, P-tau217 Eli Lilly assay, and P-tau231 Gothenburg assay strongly correlated (Spearman’s rho > 0.86), while correlations with P-tau231 ADx results were moderate (rho < 0.65). Discussion P-tau isoforms can be measured robustly by several novel high-sensitive Simoa assays.
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Chen, Yi-He, Rong-Rong Lin, Hui-Feng Huang, Yan-Yan Xue, and Qing-Qing Tao. "Microglial Activation, Tau Pathology, and Neurodegeneration Biomarkers Predict Longitudinal Cognitive Decline in Alzheimer’s Disease Continuum." Frontiers in Aging Neuroscience 14 (June 30, 2022). http://dx.doi.org/10.3389/fnagi.2022.848180.
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PurposeBiomarkers used for predicting longitudinal cognitive change in Alzheimer’s disease (AD) continuum are still elusive. Tau pathology, neuroinflammation, and neurodegeneration are the leading candidate predictors. We aimed to determine these three aspects of biomarkers in cerebrospinal fluid (CSF) and plasma to predict longitudinal cognition status using Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort.Patients and MethodsA total of 430 subjects including, 96 cognitive normal (CN) with amyloid β (Aβ)-negative, 54 CN with Aβ-positive, 195 mild cognitive impairment (MCI) with Aβ-positive, and 85 AD with amyloid-positive (Aβ-positive are identified by CSF Aβ42/Aβ40 < 0.138). Aβ burden was evaluated by CSF and plasma Aβ42/Aβ40 ratio; tau pathology was evaluated by CSF and plasma phosphorylated-tau (p-tau181); microglial activation was measured by CSF soluble TREM2 (sTREM2) and progranulin (PGRN); neurodegeneration was measured by CSF and plasma t-tau and structural magnetic resonance imaging (MRI); cognition was examined annually over the subsequent 8 years using the Alzheimer’s Disease Assessment Scale Cognition 13-item scale (ADAS13) and Mini-Mental State Exam (MMSE). Linear mixed-effects models (LME) were applied to assess the correlation between biomarkers and longitudinal cognition decline, as well as their effect size on the prediction of longitudinal cognitive decline.ResultsBaseline CSF Aβ42/Aβ40 ratio was decreased in MCI and AD compared to CN, while CSF p-tau181 and t-tau increased. Baseline CSF sTREM2 and PGRN did not show any differences in MCI and AD compared to CN. Baseline brain volumes (including the hippocampal, entorhinal, middle temporal lobe, and whole-brain) decreased in MCI and AD groups. For the longitudinal study, there were significant interaction effects of CSF p-tau181 × time, plasma p-tau181 × time, CSF sTREM2 × time, and brain volumes × time, indicating CSF, and plasma p-tau181, CSF sTREM2, and brain volumes could predict longitudinal cognition deterioration rate. CSF sTREM2, CSF, and plasma p-tau181 had similar medium prediction effects, while brain volumes showed stronger effects in predicting cognition decline.ConclusionOur study reported that baseline CSF sTREM2, CSF, and plasma p-tau181, as well as structural MRI, could predict longitudinal cognitive decline in subjects with positive AD pathology. Plasma p-tau181 can be used as a relatively noninvasive reliable biomarker for AD longitudinal cognition decline prediction.