Academic literature on the topic 'CD8+CD38+'

AbstractWhat governs the increased apoptosis sensitivity of HIV-specific CD8+ T cells is poorly understood. Here, we examined the involvement of mitochondria in this apoptosis. Remarkably higher mitochondrial mass (MM) was found in HIV-specific compared with CMV-specific CD8+ T cells from HIV+ patients and this could not be attributed to their different differentiation status. MMHigh phenotype characterized those CD8+ T cells from HIV+ patients that are sensitive to spontaneous and CD95/Fas-induced apoptosis. CD38 expression did not correlate with high MM, whereas Bcl-2 levels were significantly reduced in both CD38+ and CD38− HIV-specific CD8+ T cells. Although CD38+ HIV-specific CD8+ T cells were more susceptible to apoptosis, CD38 expression does not explain on its own the selective apoptosis sensitivity of HIV-specific CD8+ T cells, as CD38− HIV-specific CD8+ T cells were more apoptotic than CD38+ CMV-specific ones. Proapoptotic HIV-specific CD8+ T cells were CD38+Bcl-2LowMMHigh. Copolarization of mitochondria with CD95/Fas capping, very early in CD95/Fas-induced apoptosis of HIV-specific CD8+ T cells, suggests that mitochondria act as an amplification step for this apoptosis. Thus, an extensive mitochondrial network contributes to apoptosis sensitivity of CD8+ T cells and, when this occurs together with reduced levels of Bcl-2 and chronic activation, determines the proapoptotic state of HIV-specific CD8+ T cells.

Abstract CD38 is expressed in human T cells during early stages of activation and differentiation and can be used as a marker of prognosis for HIV. Currently, CD38 has raised interest since it has been found increased in patients with tuberculosis, however when the active phase is solved a decrease of CD38 in CD8 T lymphocytes is observed. Here we evaluated and determined the role of CD38 in human CD8 T lymphocytes stimulated with M. tuberculosis H37Rv soluble extracts (MTSE) and delipidized MTSE (dMTSE) in vitro. For this purpose, PBMC from healthy donors were incubated with PMA-ionomicyne, media, MTSE or dMTSE. After cultured, cells were harvested and stained with monoclonal antibodies conjugated to different fluorochromes. After kinetics experiments were performed and the expression of perforin, granzyme A, IFN-γ and CD38 in T CD8 cells was determined by flow cytometry. Expression of IFN-γ and perforin was statistically higher in T CD8+CD38+ in comparison with T CD8+CD38-. Remarkably, CD8+CD38+ T cells showed an increased cytotoxicity against macrophages pulsed with MTSE. These results suggest that the population of T CD8+ lymphocytes might have an effector functions in Ag specific dependance on CD38. This is the first report linking CTL activity to the CD38 molecule in tuberculosis.

Abstract CD38, a molecule with multilineage distribution but unknown function, and the MHC class II molecule HLA-DR (DR) have markedly elevated levels of expression on CD8+ cells of HIV-infected people. This study investigated the expression of CD38 and DR Ag on circulating HIV-specific CD8+ CTL in HIV-seropositive subjects. Purified CD8+ lymphocytes from 22 participants in the University of California at Los Angeles Multicenter AIDS Cohort Study were screened for CTL activity against autologous EBV-immortalized lymphoblast targets infected with vaccinia vectors that carried HIVIIIB gag, pol, and env genes. Sixty-seven percent (14 of 21), 64% (14 of 22), and 9% (2 of 22), respectively, of the subjects had HIV-specific CD8+ CTL activity against gag, pol, and env proteins. CD8+ cells from 11 of the subjects who had high CTL activity were then FACS-separated using three-color immunofluorescence sorting. Circulating DR-CD38- CD8+ cells had little activity. Highly purified DR+CD38+ CD8+ cells had higher HIV-specific CTL activity than other CD8+ cells. DR+CD38- or DR-CD38+ CD8+ cells also mediated significant activity, but only about half as much on a per cell basis as DR+CD38+ CD8+ cells. This is the first report that the CD38 molecule is expressed in vivo on Ag-specific CD8+ CTL, and confirms previous reports that DR is expressed on these cells. Both asymptomatic HIV-seropositive subjects (144 +/- 132/mm3) and AIDS patients (253 +/- 178/mm3) had markedly elevated levels of DR+CD38+ CD8+ cells compared with the levels in HIV-seronegative controls (7 +/- 3/mm3). However, the level of anti-HIV CTL activity was not correlated with the level of DR+CD38+ CD8+ cells, indicating that enumeration of this lymphocyte population by flow cytometry most likely will not be a useful surrogate for measuring functional CTL activity. Low levels of HIV-specific CTL activity, especially against gag, were correlated with lower CD4+ cells numbers, suggesting that the loss of CD8+ T cell cytotoxic activity against HIV that has been reported to occur with advancing HIV disease progression may reflect in part the extent of CD4+ cell immunodeficiency in HIV-infected subjects.

Abstract HIV-1 disease progression has been associated with a remarkable increase of CD8+CD38+ T-cells. It has been documented that a significant distribution of HIV-specific CD8+ T-cells resides in the CD8+CD38+ T-cell sub-population. The failure of HIV-specific CD8+CD38+ T-cells to control HIV-1 infection has been attributed to several mechanisms including apoptosis. However, the relationship between the CD38 expression and molecular events involved in CD8+ T-cell apoptosis is not well understood. We evaluated the expression of two membrane-associated apoptosis-related molecules: CXCR4 and CD95, and two cytoplasm-associated apoptosis-related molecules: Bcl-2 and active caspase-3 in 41 HIV-1 positive patients and 15 HIV-1 negative individuals. HIV-1 infection alters the level of expression of CD38, CD95, CXCR4, Bcl-2, and active caspase-3. A positive correlation was established between CD95, CXCR4, and active caspase-3 expression with low CD4 count and high plasma viremia and CD38 expression. The majority of activated CD8+CD38+ T-cells were apoptotic since they expressed active caspase-3 and the rest of these cells were susceptible to become apoptotic since they co-expressed CD95 and CXCR4. We suggest that one of the most likely HIV-mediated apoptosis mechanisms is via CD95 and CXCR4 induction through the caspase cascade despite Bcl-2 expression. This provides another explanation of why HIV-1 infection is not fully contained by HIV-specific CD8+CD38+ T-cells. Supported by NIH/RCMI Grant # G12-RR03035.

Background:We recently reported the beneficial clinical responses of the anti-CD38 monoclonal antibody daratumumab in two patients with systemic lupus erythematosus (SLE) [1]. While the primary rationale for its use was the depletion of autoantibody-producing long-lived plasma cells, daratumumab may promote additional therapeutic effects on CD38-expressing T cells, but their origin, lifestyle and role in lupus pathophysiology remains elusive.Objectives:To investigate the phenotype, transcriptional program, functional properties and clinical associations of CD4+ and CD8+CD38+ memory T cells in SLE compared to healthy controls (HC).Methods:CD38-expression on memory T cell subsets was measured by flow cytometry in 65 patients with SLE and 28 healthy controls. We investigated the functional capacity of CD38+ T cells using CFSE staining and intracellular cytokine staining after polyclonal stimulation. Additionally, we performed single-cell transcriptome and T-cell-receptor sequencing of 7 SLE patients and 7 matched healthy controls, including surface protein expression analysis using CITE-seq (RNA-barcoded) antibodies.Results:Compared to healthy controls, the frequency of CD38-expressing memory T cells in SLE was significantly increased in both CD4+ and CD8+ T cells. SLE patients with a previous or current lupus nephritis had significantly increased levels of CD8+CD38+ memory T cells compared to those without history of renal involvement. CD38+ memory T cells expressed increased levels of Ki-67 and displayed higher proliferative capacity upon polyclonal stimulation than their CD38- counterparts, both in SLE patients and HC, while they showed decreased ability to secrete IFN-γ, IL-2, GM-CSF and TNF-α. Single-cell transcriptome sequencing revealed that CD8+CD38+ memory T cells were enriched within terminally differentiated, cytotoxic CD8 T cells, and had reduced TCR repertoire diversity compared to their CD38- counterparts. CD8+CD38+ memory T cells from SLE patients had significantly higher expression of type I interferon associated genes, both compared to CD38- memory T cells from SLE patients and CD38+ cells from HCs.Conclusion:CD38+ memory T cells with increased proliferative capacity but altered effector functions are significantly expanded in peripheral blood of SLE and correlate with the lupus nephritis. Although the factors mediating their generation and their precise role in the disease pathophysiology remain to be investigated, CD38-expressing T cells may be useful as a future biomarker for lupus nephritis.References:[1]Ostendorf L, Burns M, Durek P, Heinz GA, Heinrich F, Garantziotis P, et al. Targeting CD38 with Daratumumab in Refractory Systemic Lupus Erythematosus. N Engl J Med. 2020 Sep 17;383(12):1149–55.[2]Katsuyama E, Suarez-Fueyo A, Bradley SJ, Mizui M, Marin AV, Mulki L, et al. The CD38/NAD/SIRTUIN1/EZH2 Axis Mitigates Cytotoxic CD8 T Cell Function and Identifies Patients with SLE Prone to Infections. Cell Reports. 2020 Jan;30(1):112-123.e4.Acknowledgements:We thank our patients and healthy controls for making our research possible.Disclosure of Interests:None declared.

We investigated the effect of LPSin vitrostimulation on T-cell activation in HIV-infected patients with different CD4+ recovery on HAART. PBMCs from 30 HIV-positive, HAART-treated, aviremic individuals with different CD4+ reconstitution (Low Responders: CD4+ < 350/μL; Intermediate Responders: CD4+ 350–599/μL; High Responders: CD4+ ≥ 600/μL) were cultured with LPS and the proportion of HLA-DR/CD38- and Ki67-expressing CD4+/CD8+ T-cells was measured (flow cytometry). Upon LPS stimulation, significantly higher CD4+ and CD8+HLA-DR+ cells were shown in LR and IR versus HIV-negative controls. While no differences in the proportion of LPS-stimulated CD4+CD38+ cells were recorded amongst HIV-positive subgroups, CD8+CD38+ cells were more elevated in patients with lower CD4+ recovery on HAART (i.e., LR and IR). Uponin vitroLPS stimulation, HLA-DR and CD38 expression on T-cells are differentially regulated. While HLA-DR induction reflects impaired CD4+ reconstitution on HAART, cell-surface CD38 expression is increased only on CD8+ T-cells, allowing to speculate that the sole induction of CD38 on CD4+ cells may not be sufficient to depict LPS-driven immune activation in HIV.

Objectives. We investigated immune phenotypes of HIV+ patients who present late, considering late presenters (LPs, CD4+ < 350/μL and/or AIDS), advanced HIV disease (AHD, CD4+ < 200/μL and/or AIDS), and AIDS presenters (AIDS-defining condition at presentation, independently from CD4+).Methods. Patients newly diagnosed with HIV at our clinic between 2007–2011 were enrolled. Mann-Whitney/Chi-squared tests and logistic regression were used for statistics.Results. 275 patients were newly diagnosed with HIV between January/2007–March/2011. 130 (47%) were LPs, 79 (29%) showed AHD, and 49 (18%) were AIDS presenters. LP, AHD, and AIDS presenters were older and more frequently heterosexuals. Higher CD8+%, lower CD127+CD4+%, higher CD95+CD8+%, CD38+CD8+%, and CD45R0+CD38+CD8+% characterized LP/AHD/AIDS presentation. In multivariate analysis, older age, heterosexuality, higher CD8+%, and lower CD127+CD4+% were confirmed associated with LP/AHD. Lower CD4+ and higher CD38+CD8+% resulted independently associated with AIDS presentation.Conclusions. CD127 downregulation and immune activation characterize HIV+ patients presenting late and would be studied as additional markers of late presentation.

BackgroundImmune check-point blockade (ICB) is one of the emerging therapeutic options for advanced hepatocellular carcinoma (HCC). However, low response rates amongst patients necessitates the development of robust predictive biomarkers that identify patients who likely benefit from ICB. Previously our group found that immunohistochemical scoring of CD38 in the tumour microenvironment predicts responsiveness to anti-PD-1/anti-PD-L1 immunotherapy in HCC.1 Recently BMS 4-gene inflammatory signature, comprising the 4 genes CD8, PD-L1, LAG-3 and STAT1, has been shown to be associated with better overall response to immunotherapy in various cancer types.2–4 In the present study, we examined the relationship between tissue expression of BMS 4-gene inflammatory signature and the responsiveness of HCC to immunotherapy, and whether BMS 4-gene inflammatory signature increases the predictive power of CD38.MethodsHCC tissue samples from 124 Asian patients that underwent conventional treatment and from 49 Asian patients that underwent ICB were analysed for CD8, PD-L1, LAG-3, STAT1, CD38 and CD68 tissue expression using immunohistochemistry and multiplex immunohistochemistry, followed by survival and statistical analysis.ResultsSurvival analysis of the 124 samples showed that high LAG-3 tissue expression was associated with shorter progression-free survival (PFS). On the other hand, immunohistochemical analyses on the 49 patient samples treated with ICB revealed that high LAG-3 density and high total LAG-3+CD8+ T cell proportion were associated with improved response to ICB (figure 1). However, CD8, PD-L1 and STAT1 levels did not significantly correlate with improved survival. The addition of total LAG-3+ cell proportion to total CD38+ cell proportion significantly increased the predictive value for both PFS (DeltaLRChi2=9.97; P=0.0016; table 1) and overall survival (OS) (DeltaLRChi2=8.84; P=0.0021; table 1), compared with total CD38+ cell proportion alone. Similarly findings were obtained after adding total LAG-3+CD8+ cell proportion to total CD38+ cell proportion (PFS: DeltaLRChi2=7.21; P=0.0072; OS: DeltaLRChi2=8.06; P=0.0045; table 1), compared with total CD38+ cell proportion alone. Lastly, when the total LAG-3+CD8+ cell proportion was added to total CD38+ and CD38+CD68+ cell proportion, the predictive value of the biomarker was significantly increased (PFS: DeltaLRChi2=6.10; P=0.0136; OS: DeltaLRChi2=6.18; P=0.0129; table 1). Ongoing works include further validation of the findings in various cohorts, and correlating with clinical outcome of the patients.Abstract 89 Table 1Log-likelihood of models with added predictive termsAbstract 89 Figure 1HCC patients‘ response to ICB in relation to LAG-3 density. (A) Kaplan-Meier curve showing the association between a high LAG-3 density and improved overall survival after treatment with ICB. (B) Kaplan-Meier curve showing the association between a high total LAG-3+CD8+ T cell proportion and improved overall survival after treatment with ICB. (C) Kaplan-Meier curve showing the association between a high LAG-3 density and improved progression-free survival after treatment with ICB. (D) Kaplan-Meier curve showing the association between a high total LAG-3+CD8+ T cell proportion and improved progression-free survival after treatment with ICB.ConclusionsHigh LAG-3 expression on tissue-infiltrating immune cells predicted greater response to ICB. LAG-3+ and LAG3+CD8+ cell proportion added predictive value to CD38+ cells for predicting survival outcome in immunotherapy-treated HCC. LAG-3 may be used in conjunction with CD38 to predict responsiveness to ICB in HCC.ReferencesNg HHM, Lee RY, Goh S, et al. Immunohistochemical scoring of CD38 in the tumor microenvironment predicts responsiveness to anti-PD-1/PD-L1 immunotherapy in hepatocellular carcinoma. J Immunother Cancer 2020;8.Hodi FS, Wolchok JD, Schadendorf D, et al. Abstract CT037: Genomic analyses and immunotherapy in advanced melanoma. AACR 2019.Lei M, Siemers NO, Pandya D, et al. Analyses of PD-L1 and Inflammatory Gene Expression Association with Efficacy of Nivolumab ± Ipilimumab in Gastric Cancer/Gastroesophageal Junction Cancer. Clinical Cancer Research 2021;27:3926–35.Sangro B, Melero I, Wadhawan S, et al. Association of inflammatory biomarkers with clinical outcomes in nivolumab-treated patients with advanced hepatocellular carcinoma. J Hepatol 2020.Ethics ApprovalThis study was approved by the Centralised Institutional Review Board of SingHealth (CIRB ref: 2009/907/B).ConsentWritten informed consent was obtained from the patient for publication of this abstract and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.

We have examined CD8+ sub-populations to determine whether these subsets are critical to the production of CD8+ T cell nonlytic factors. The production of the beta-chemokines MIP-1alpha, MIP-1beta and RANTES, and the chemoattractant cytokine IL-16 were measured in cells derived from 24 HIV-infected and 25 uninfected subjects. Asymptomatic HIV+ subjects (CD4 > 200/ul) produced significantly higher levels of MIP-1alpha and MIP-1beta from CD8+ T cells and some sub-phenotypes. Higher RANTES levels were produced by CD28-, CD38- and HLA-DR+/- sub-phenotypes. However, IL-16 was only modulated in the CD38+ subset in comparison to total CD8+ T cells. Infection of CD8+ T cells and sub-populations resulted in generally increased levels of chemokine and IL-16 production, which dissipated over a 15 day time course. Moreover, CD8+ antiviral factor (CAF) activity, another major component of CD8+ T cell nonlytic suppression factors, was not associated with chemokine production. However, significantly higher levels of CAF were produced by CD38+ and HLA-DR+ sub-populations. In addition, we also showed that in CD8+ T cell populations, the production of MIP-1alpha, MIP-1beta and IL-16 was inversely correlated with virus copy number. These findings shed light on the noncytotoxic responses of CD8+ T cells in controlling the natural course of HIV infection.

INTRODUÇÃO: A Síndrome de Sézary (SS) é um linfoma cutâneo de células T (LCCT), caracterizado por eritrodermia, linfadenopatia generalizada e presença de células tumorais na pele, linfonodos e sangue periférico. Os linfócitos TCD8+ têm papel fundamental na resposta imune antitumoral, entretanto, há escassos estudos evidenciando seu perfil fenotípico e funcional. Considerando que a resposta imunológica do paciente com SS está suprimida, estratégias para potencializar a imunidade inata e adaptativa com agonistas de receptores Toll-like (TLRs) têm sido exploradas. OBJETIVO: Caracterizar o perfil de marcadores de ativação/inibição das células TCD8+, seus estágios de diferenciação, capacidade de resposta a IL-7/IL-15 e ao agonista de TLR7/TLR8 de pacientes com SS. METODOLOGIA: Foram selecionados 15 pacientes com SS (7 homens e 8 mulheres) com 48-85 anos do Ambulatório de Linfomas Cutâneos, do HC-FMUSP, e um grupo de controle com 24 indivíduos sadios. A análise de marcadores de ativação/inibição e diferenciação celular em células TCD4/TCD8+ do sangue periférico foi realizada por citometria de fluxo. A expressão de marcadores extracelulares e citocinas intracelulares em células mononucleadas do sangue periférico (CMN) após estimulação com o agonista de TLR7/TLR8 foi analisada por citometria de fluxo. Além disto, o efeito de IL-7 e IL-5 em células T foi avaliado pela fosforilação de STAT5, na capacidade de proliferação mitogênica e expressão de BCL-2 em CMNs, como também pelos níveis séricos de IL-7 por citometria de fluxo. RESULTADOS: Os pacientes com SS mostram perfil fenotípico de ativação crônica nos linfócitos TCD8+ periféricos, decorrente do elevadopercentual de células TCD8+ CD38+, redução percentual de TCD8+ CD127+ (IL-7R) e da população naive. Além disso, ocorreu aumento de expressão de PD-1 na população naive de células TCD8+. O marcador de ativação, CD26, até então apenas relacionado com linfócitos TCD4, foi detectado em reduzida percentagem de linfócitos TCD8. A resposta para IL-7/IL-15 parece estar funcionalmente presente tanto nos linfócitos TCD4 quanto nos linfócitos TCD8. Contudo, foi encontrado um perfil diferenciado e heterogêneo de fosforilação de STAT5 assim como de expressão de BCL-2 nos linfócitos TCD8+ de pacientes com SS. O nível sérico de IL-7 reduzido dos pacientes com SS foi inversamente correlacionado com o número absoluto de linfócitos TCD4+. CONCLUSÃO: Os linfócitos TCD8+ dos pacientes com SS encontram-se reduzidos em números absolutos, e possuem um perfil alterado de diferenciação celular e expressão de marcadores extracelulares. A redução percentual da população de TCD8+ naive associada com a presença de moléculas de ativação crônica mostra um perfil de imunosenescência. As células TCD8+ exibem baixa capacidade de resposta aos ligantes de TLR intracelulares, provavelmente devido ao perfil de ativação crônica. Além disso, há resposta parcial dos linfócitos TCD8+ às citocinas ligantes do receptor yc. Nossos resultados evidenciam alterações em linfócitos TCD8+ que debilitam a resposta imune antitumoral e que pode contribuir com a patogênese da síndrome de Sézary
INTRODUCTION: Sézary syndrome (SS) is a cutaneous T cell lymphoma (CTCL), characterized by erythroderma, generalized lymphadenopathy and the presence of tumor cells in the skin, lymph nodes and peripheral blood. The TCD8+ lymphocytes play a key role in anti-tumor immune response, whereas, there are few studies showing its phenotypic and functional profile in SS. Considering that the immune response of SS patient is suppressed, strategies to enhancing the innate and adaptive immunity by Toll-like receptors (TLRs) agonists have been explored. OBJECTIVE: To characterize the profile of activation/inhibition markers of CD8+ T cells, their stages of differentiation, ability of response to IL-7/IL-15 and TLR7/TLR8 agonist of patients with SS. METHODOLOGY: Fifteen SS patients were enrolled (7 men and 8 woman) with 48-85 years from the Clinic of Cutaneous Lymphomas, HC-FMUSP, and a control group of 24 healthy individuals. Analysis of activation/inhibition markers and cellular differentiation in CD4/CD8 T cells from peripheral blood were assessed by flow cytometry. The expression of extracellular markers and intracellular cytokines in mononuclear cells in the peripheral blood (CMN) were evaluated by flow cytometry. Moreover, the effect of IL-7 and IL-15 stimulation in T cells was assessed by the STAT5 phosphorylation, proliferative mitogenic capacity, BCL-2 expression in CMNs as well as serum IL-7 levels by flow cytometry. RESULTS: Patients with SS show a phenotypic CD8 T peripheral lymphocytes profile of chronic activation, due to the high percentage of CD8+CD38+ T cells, reduced percentage of CD8+CD127+ (IL-7R) and naïve population. Furthermore, it was observed an increased PD-1 expression in the naïve CD8+ T cells. The activation marker CD26, previously only associated with CD4 T lymphocyte, was detected at decreased percentage in CD8 T lymphocytes. The TLR7/TLR8 agonist did not affect the IFN-? and TNF secretion of CD8 T lymphocytes of SS patients, in contrast to the control group. The response to IL-7/IL-15 appears to be functional in both CD4 and CD8 T lymphocytes. However, it was founded a differentiated and heterogeneous profile of STAT5 phosphorylation and Bcl-2 expression in the CD8 T lymphocytes in SS patients. The reduced IL-7 serum of patients with SS was inversely correlated with the absolute number of CD4 T lymphocytes. CONCLUSION: CD8 T lymphocytes of patients with SS are reduced in absolute numbers, and show an altered cellular differentiation profile and extracellular markers expression. The reduced percentage of CD8 naïve population associated with chronic activation of molecules reveals an immunosenescence profile. The CD8 T cells exhibit low ability to ligands of intracellular TLR receptors, probably due to chronic activation profile. In addition, there are partial response of CD8 T lymphocytes to the cytokine receptor ?c. Our results show disturbance in CD8 T lymphocytes that may impair the anti-tumor response contributing to the pathogenesis of Sézary syndrome

Background: Infection/reactivation Cytomegalovirus (CMV) is a major cause of morbidity and mortality in immunocompromised hosts. It has already been observed in patients that have undergone kidney or liver transplantation, that CMV disease is accompanied by significant increase of circulating CD8+CD38+ T lymphocytes. In patients that received haematopoietic stem-cells (HSCT), there are no reports that address the study of this subpopulation in monitoring/diagnosis of CMV disease. Objectives: This study aimed to evaluate some cellular activation markers on circulating T lymphocytes (CD38 and HLA-DR), by flow cytometry, in patients undergoing HSCT and to stablilish its correlation with CMV disease. Methods: Blood samples of 15 patients undergoing HSCT were analysed by flow cytometry, using the following monoclonal antibodies: anti-CD3, anti-CD4, anti-CD8, anti-CD38, anti-HLA-DR, and the results were compared to CMV antigenemia, held by indirect immunofluorescence. Minitab for Windows was used for statistical analysis and a p-value < 0.05 was considered significant. Results: Patients with positive antigenemia did not show any significant increase in the percentuals of T CD8+cells expressing the activation markers CD38 or HLADR when compared to patients with negative antigenemia. On the contrary, all patients showed high percentuals of these cells independent of the presence of CMV disease. Conclusions: This study suggests that, in patients undergoing HSCT, the study of these lymphocyte sub-populations doesn't seem to contribute to the early identification of the CMV disease.
Introdução: A infecção/reativação por citomegalovírus (CMV) é uma das principais causas de morbi/mortalidade em pacientes imunossuprimidos. Já foi observado em pacientes transplantados de rim e fígado, que este processo é acompanhado de aumento significativo de linfócitos T CD8+CD38+ circulantes. Em pacientes que receberam Transplante de Células Tronco-Hematopoiéticas (TCTH) não há relatos que abordem o estudo desta subpopulação na vigilância/diagnóstico da doença por CMV. Objetivos: Este estudo pretendeu avaliar marcadores de ativação celular em linfócitos T circulantes (CD38 e HLA-DR), por citometria de fluxo, em pacientes submetidos ao TCTH e sua correlação com a infecção/reativação por CMV. Métodos: Amostras de sangue de 15 pacientes submetidos ao TCTH foram analisadas, por citometria de fluxo, utilizando os anticorpos monoclonais anti-CD3, anti-CD4, anti-CD8, anti-CD38, anti-HLADR e os resultados comparados com a antigenemia para CMV, realizada por imunofluorescência indireta. Utilizou-se o programa Minitab for Windows para as análises estatísticas e o valor de p < 0,05 foi considerado como significante. Resultados: Os pacientes com antigenemia positiva não apresentaram aumento significativo nos percentuais de linfócitos TCD8+ expressando os marcadores de ativação celular CD38 e HLADR, quando comparados com os pacientes com antigenemia negativa. Surpreendentemente, observou-se que ambos os grupos apresentaram percentuais extremamente elevados de linfócitos ativados, independente da presença de doença por CMV. Conclusão Este estudo sugere que, em pacientes submetidos ao TCTH, o estudo de sub-populações linfocitárias circulantes ativadas não parece contribuir para a identificação precoce da doença por CMV.

Hepatitis C is a blood-borne infection caused by the hepatitis C virus (HCV). A chronic infection, which develops in most infected subjects, may lead to liver cirrhosis with ensuing liver dysfunction and liver cancer. About 30% of HIV-positive patients are coifected with HCV. The standard of care in HIV-HCV-coinfected subjects was a combination of pegylated interferon (peg-IFN)-alpha and ribavirin for 48 weeks until few months ago. The eradication of HCV was obtained in 20-55% of cases albeit with significant side effects. Further understanding of host factors that determine the effectiveness of treatment may provide diagnostic tools to distinguish patients who will be cured from those in whom treatment is likely to be futile. The aim of this thesis was to identify biomarkers and some conditions to predict outcome of combination therapy in HIV-HCV-infected patients. The parameters studied included microbial translocation markers as sCD14 and LPS, immune activation profile as CD8+CD38+, CD4+/CD8+ ratio, and in added a HAART intensification with CCR5 inhibitors, maraviroc. We showed that in HIV-HCV patients sCD14 correlates with the severity of liver disease and predicts early response to peg-IFN-apha/ribavirin. Moreover, during anti-HCV therapy there is a higher immune activation by CD8+CD38+ increasing. This data could be a major factor for outcome above all in the first phases of therapy. In conclusion, we evaluated that HAART intensification with maraviroc Per concludere si è valutato come l’intensificazione della terapia HAART con maraviroc could increase T CD4+ recovery and translate in higher probability of sustained virological response in immunological non responder subjects.

碩士
長庚大學
生物醫學研究所
102
Hepatitis C virus (HCV) is a common cause of liver disease worldwide. The persistent infection of HCV is associated with impaired CD8 T cell function. Chronic infection can lead to fibrosis of the liver and ultimately to cirrhosis, which is generally apparent after decades. In some cases, those with cirrhosis will go on to develop liver cancer even die. Human leukocyte antigen-DR (HLA-DR) and CD38 are expressed by activated T cells during the acute phase of viral infections in humans. Previous studied indicated that the populations of CD38+HLADR+CD8+ T cells were increased when infected with Human Immunodeficiency Virus, Epstein–Barr virus and Hepatitis B virus. However, the role of CD38+HLADR+CD8+ T cells during chronic HCV infection is poor described and their function has not been studied yet. In my study, results showed that the percentage of CD38+HLADR+CD8+ T cells in peripheral blood of chronic HCV patients was significantly increased when compared with healthy volunteer. The CD38+HLADR+CD8+ T cells have increased expression of cytotoxitc molecules but also with higher levels of inhibitory receptor than CD38-HLADR-CD8+ T cells. In addition, results showed these cells would accumulate in the inflamed liver. Results indicated that the both HCV specific and non-HCV-specific CD8+ T cells contributed to the increase of CD38+HLADR+CD8+ T cells in patients with chronic hepatitis C. Moreover, the CD38+HLADR+CD8+ T cells would behave as innate CD8+ T cells and produce IFN-γ by cytokine-dependent pathway. Taken together, we suggest that during chronic HCV infection, these CD38+HLADR+CD8+ T cells, both HCV-specific and non-HCV specific, were increased and accumulated in the liver. Their role in the chronic hepatitis C needs to be elicited in the subsequent studies.

Introduction: Virus-specific CD8+ T cells are crucial to suppress the viral replication in HIV infection. Their functional status is important as well. Also, the chronic nonspecific immune activation of T and B lymphocytes plays an important role in the immunopathogenesis of HIV infection. Aim of the study: To analyze the frequency and functional status of HIV-specific CD8+ T cells and the expression of nonspecific activation markers on B and T cells in HIV+ patients and to assess the effect of combined antiretroviral therapy (cART) on these parameters. Patients and methods: Our cohort included 80 HIV+ patients: 36 HIV+ patients on cART, 18 patients without therapy, in whom cART was introduced during our study, 9 patients without therapy, 10 patients with primary HIV infection, 3 long-term non-progressors and 4 patients initially on cART, in whom the therapy was discontinued. Control group consisted of 34 HIV- healthy individuals. We examined CD4+ a CD8+ T cell counts, viral load, expression of nonspecific activation markers on T cells and the frequency of HIV-specific CD8+ T cells by ELISpot method and flow cytometry using MHC tetramers and intracellular cytokine detection. Results: No significant differences in HIV-specific CD8+ T cells were found between treated and untreated HIV+ patients. The frequency...

CD38 is a transmembrane glycoprotein expressed on the surface of different cell lines with several functions (receptor, adhesion molecule, ectoenzyme). Based on its high expression in multiple myeloma cells, CD38 is one of the main molecules used in the target therapy age. Daratumumab is the first fully human monoclonal antibody tested in clinical trials, showing efficacy in relapsed/refractory multiple myeloma patients, especially in combination with immunomodulants and/or proteasome inhibitors. The synergic effect concerns multiple myeloma cells as well as the microenvironment (NK cells, macrophage, regulatory B/T cells and CD8+ effector cells). Therefore, the anti-multiple myeloma activity of Daratumumab greatly depends on the immune system: this is the reason why several ongoing clinical trial are testing its efficacy in the naïve patients, with a more effective immune system.