Статті в журналах: "Immunoglobulin A; Immunoglobulin G; Antigens"

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Красавцев, Е. Л., and М. В. Подоляко. "Detection Rate of Immunoglobulins G to Toxocar Antigens in the Republic of Belarus." Педиатрия. Восточная Европа, no. 3 (November 3, 2022): 319–24. http://dx.doi.org/10.34883/pi.2022.10.3.003.

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Цель. Изучить частоту выявления иммуноглобулинов G к антигенам токсокар у детей в различных регионах Республики Беларусь, различного возраста, пола.Материалы и методы. Анализ на иммуноглобулины G к антигенам токсокар был взят у 11 541 ребенка. Сравнение частоты выявления иммуноглобулинов G к антигенам токсокар у детей, проживающих в различных регионах Республики Беларусь, различного пола, возраста было произведено методами непараметрической статистики (таблицы 2×2, критерий χ2).Результаты. В результате исследования 11 541 ребенка иммуноглобулины G к антигенам токсокар были выявлены у 1153 человек (10,0%). Наиболее часто иммуноглобулины G к антигенам токсокар регистрировались в возрастной группе от 12 до 15 лет (15,1%), реже – в возрасте до 3 лет (6,9%, р<0,001, χ2=6,7). Самый большой процент положительных результатов зарегистрирован у детей в Могилевской области (15,2%), а самый низкий – у детей в г. Минске (7,9%) и Гомельской области (10,1%). Наиболее часто иммуноглобулины G к антигенам токсокар выявлялись у детей городов Орши (18,75%) и Бобруйска (17,6%), реже – у жителей Борисова (5,3%, р<0,001) и Новополоцка (6,7%, р<0,001).Выводы. В Республике Беларусь частота обнаружения у детей иммуноглобулинов G к антигенам токсокар имеет возрастные и региональные особенности. Наиболее часто иммуноглобулины G к антигенам токсокар отмечались в возрастной группе от 12 до 15 лет (15,1%), реже – в возрасте до 3 лет (6,9%, р<0,001, χ2=6,7). Purpose. To study the detection rate of immunoglobulins G to toxocar antigens in children of different age and gender from different regions of the Republic of Belarus.Materials and methods. Immunoglobulin G tests for toxocar antigens were performed in 11,541 children. The detection rate of immunoglobulin G to toxocar antigens in children of different gender and age living in different regions of the Republic of Belarus was compared using nonparametric statistics (Tables 2×2, χ2 criterion).Results. A survey of 11,541 children revealed G immunoglobulins to toxocar antigens in 1,153 individuals (10.0%). Immunoglobulins G to toxocar antigens were most frequently registered in the age group of 12 to 15 years (15.1%), and less frequently in the age group under 3 years (6.9%, p<0.001, χ2=6.7). The highest percentage of positive results was registered among children living in the Mogilev region (15.2%), and the lowest one among children living in the city of Minsk (7.9%) and in the Gomel region (10.1%). Immunoglobulins G to toxocar antigens were most frequently revealed in children of Orsha (18.75%) and Bobruisk (17.6%), and less often in residents of Borisov (5.3%, p<0.001) and Novopolotsk (6.7%, p<0.001).Conclusions. In the Republic of Belarus, the detection rate of immunoglobulin G to toxocar antigens in children varies by age and region. Immunoglobulin G to toxocar antigens was revealed most frequently in the age group of 12–15 years (15.1%), and less frequently in the age group under 3 years (6.9%, p<0.001, χ2=6.7).

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Okamoto, Yasuyuki, Noboru Hamada, Toshimichi Fujisawa, Jaeduk Noh, Junichi Yamakawa, Mariko Ohno, Kunihiko Ito, and Hirotoshi Morii. "Why no simple relationship between thyroid peroxidase activity-inhibiting immunoglobulins and thyroid function in autoimmune thyroid disease?" Acta Endocrinologica 124, no. 4 (April 1991): 442–48. http://dx.doi.org/10.1530/acta.0.1240442.

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Abstract. We have reported that some anti-thyroid peroxidase antibodies inhibit the activity of thyroid peroxidase in vitro. These thyroid peroxidase activity-inhibiting immunoglobulins seem to inhibit thyroid function in some patients, but the relationship between thyroid peroxidase activity-inhibiting immunoglobulins and thyroid function is not simple. We designed this study to explore this lack of a simple relationship. We stained immunoglobulin G deposits by immunofluorescence staining or the peroxidase-antiperoxidase method, and stained endogenous thyroid peroxidase activity by enzyme histochemistry in thyroid sections. When cryostat thyroid sections were incubated with thyroid peroxidase activity-inhibiting immunoglobulins, immunoglobulin G deposits were seen as lines of stain on the apical border and as intracellular staining, and endogenous thyroid peroxidase activity was inhibited. In paraffin-embedded thyroid sections from 5 Hashimoto's patients and 6 Graves' patients, immunoglobulin G deposits were not found on the apical border of the follicular epithelium. In frozen thyroid sections from 22 Graves' patients, no clear deposits of immunoglobulin G on this apical border were seen. In organ-cultured thyroid slices incubated with thyroid peroxidase activity-inhibiting immunoglobulins, endogenous thyroid peroxidase activity was not inhibited. In conclusion, thyroid peroxidase activity-inhibiting immunoglobulins may reach its antigen only with difficulty. This is one of the reasons why no simple relationship is observed between thyroid peroxidase activity-inhibiting immunoglobulins and thyroid function.

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Toar, Wisje Lusia, Laurentius Rumokoy, Ivonne Maria Untu, and Geertruida Assa. "Insect Crude Thoraxial Antigen-G Extracted from Apis mellifera to Enhance Serum Immunoglobulin of Goats: An Entomology Contribution in Animal Science." ANIMAL PRODUCTION 20, no. 2 (July 30, 2019): 133. http://dx.doi.org/10.20884/1.jap.2018.20.2.608.

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This research was conducted to evaluate the influence of insect crude thoraxial antigen-G (CTA) extracted from Apis mellifera L. (Hymenoptera: Apidae) to enhance goat’s serum immunoglobulin level. The first part of this study was the determination of insect CTA proportion level. The insects were collected from four different places: Tomohon, Minahasa, North-Minahasa and Manado areas. The second part of the study was the application of A. mellifera CTA substance on serum immunoglobulin level classification. In this part, twelve young goats handled with traditional maintenance. The animals experiment were divided in two groups: control group and the other treated with 100 µg CTA extract. The proportion of serum immunoglobulins level of goats was detected at 14th days after immunization with insects CTA extract, and compared with the animals immunoglobulin levels at the starting day of treatment. The data of CTA extract proportion level of the insects collected were subjected to statistically analysis using the general linear model (GLM) procedure of SPSS 22. Concerning the classification level of the animal treated with CTA was statistically analyzed according to Mann-Whitney test. The results showed that the proportion level of thoraxial antigens-G of A. mellifera from all areas observed were not significant different (P>0.05). This crude thoraxial antigens-G of this insect were able to increase serum antibody level of the experiment animal after 14 days of immunization. The immunoglobulin level qualification of animals in treated group were significant higher (P<0.05) than in control group. We concluded that the CTA extract of the Apis mellifera could be empowered to improve the young goat immunity against the pathogenic microbes in their environment.

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Duthie, Malcolm S., Isabela M. B. Goulart, Steven G. Reed, Janaina Lobato, and Luiz R. Goulart. "Immunoglobulin G and M Detection for Leprosy Diagnosis (129.18)." Journal of Immunology 182, no. 1_Supplement (April 1, 2009): 129.18. http://dx.doi.org/10.4049/jimmunol.182.supp.129.18.

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Abstract Leprosy is a curable disease that requires better diagnostic and prognostic tools to accompany preventive and therapeutic strategies. Circulating IgM antibodies against the M. leprae phenolic glycolipid-I (PGL-I) antigen have previously been used to assess humoral immunity. The presence of elevated titers of anti-PGL-I IgM reflects total bacterial load in the body; these antibodies, however, are generally low or absent in paucibacillary patients. Our objective was to compare 3 new recombinant antigens, ML0405, ML2331, and LID1 (comprising critical regions from ML0405 and ML2331), which recognize serum IgG, in comparison and in combination with PGL-I IgM. Serum samples were collected from 105 patients across the leprosy spectrum at the initial diagnosis and again after treatment. Patient positivity for LID1, ML0405, ML2331 and PGL-I tests was 67%, 62%, 65%, and 76%, respectively. A combination of the LID1 and PGL-1 antigens gave a positivity of 80%. After treatment, the ML0405 and PGL-I assays decreased their ELISA index values for all clinical forms, except for the LL form. Importantly, both antigens have been positively correlated with the bacillary load, clinical forms and the operational classification at diagnosis. Our results suggest that the combination of LID1 and PGL-I antigens, recognizing the IgG and IgM response, respectively, could be employed as an auxiliary tool for leprosy diagnosis. This work was funded in part by American Leprosy Mission.

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Yamagata, G. Richard, Laurel J. Gershwin, and Ming M. Wong. "Immunoglobulin E recognition of Dirofilaria immitis antigens is more specific than immunoglobulin G." Veterinary Parasitology 44, no. 3-4 (October 1992): 223–45. http://dx.doi.org/10.1016/0304-4017(92)90119-t.

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Weber, Alfred, Andrea Engelmaier, and Sonja Haindl. "Long-term stability of immunoglobulin G antibodies against bacterial antigens in human immunoglobulin G-deficient serum." Journal of Allergy and Clinical Immunology 145, no. 2 (February 2020): AB177. http://dx.doi.org/10.1016/j.jaci.2019.12.374.

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Gasperi, Christiane, Till F. M. Andlauer, Ana Keating, Benjamin Knier, Ana Klein, Verena Pernpeintner, Peter Lichtner, et al. "Genetic determinants of the humoral immune response in MS." Neurology - Neuroimmunology Neuroinflammation 7, no. 5 (July 16, 2020): e827. http://dx.doi.org/10.1212/nxi.0000000000000827.

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ObjectiveIn this observational study, we investigated the impact of genetic factors at the immunoglobulin heavy chain constant locus on chromosome 14 and the major histocompatibility complex region on intrathecal immunoglobulin G, A, and M levels as well as on B cells and plasmablasts in the CSF and blood of patients with multiple sclerosis (MS).MethodsUsing regression analyses, we tested genetic variants on chromosome 14 and imputed human leukocyte antigen (HLA) alleles for associations with intrathecal immunoglobulins in 1,279 patients with MS or clinically isolated syndrome and with blood and CSF B cells and plasmablasts in 301 and 348 patients, respectively.ResultsThe minor alleles of variants on chromosome 14 were associated with higher intrathecal immunoglobulin G levels (β = 0.58 [0.47 to 0.68], lowest adjusted p = 2.32 × 10−23), and lower intrathecal immunoglobulin M (β = −0.56 [−0.67 to −0.46], p = 2.06 × 10−24) and A (β = −0.42 [−0.54 to −0.31], p = 7.48 × 10−11) levels. Alleles from the HLA-B*07:02-DRB1*15:01-DQA1*01:02-DQB1*06:02 haplotype were associated with higher (lowest p = 2.14 × 10−7) and HLA-B*44:02 with lower (β = −0.35 [−0.54 to −0.17], p = 1.38 × 10−2) immunoglobulin G levels. Of interest, different HLA alleles were associated with lower intrathecal immunoglobulin M (HLA-C*02:02, β = −0.45 [−0.61 to −0.28], p = 1.01 × 10−5) and higher immunoglobulin A levels (HLA-DQA1*01:03-DQB1*06:03-DRB1*13:01 haplotype, β = 0.40 [0.21 to 0.60], p = 4.46 × 10−3). The impact of HLA alleles on intrathecal immunoglobulin G and M levels could mostly be explained by associations with CSF B cells and plasmablasts.ConclusionAlthough some HLA alleles seem to primarily drive the extent of humoral immune responses in the CNS by increasing CSF B cells and plasmablasts, genetic variants at the immunoglobulin heavy chain constant locus might regulate intrathecal immunoglobulins levels via different mechanisms.

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Hoelzle, L. E., K. Hoelzle, M. Ritzmann, K. Heinritzi, and M. M. Wittenbrink. "Mycoplasma suis Antigens Recognized during Humoral Immune Response in Experimentally Infected Pigs." Clinical and Vaccine Immunology 13, no. 1 (January 2006): 116–22. http://dx.doi.org/10.1128/cvi.13.1.116-122.2006.

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ABSTRACT Today, serodiagnostic tests for Mycoplasma suis infections in pigs have low accuracies. The development of novel serodiagnostic strategies requires a detailed analysis of the humoral immune response elicited by M. suis and, in particular, the identification of antigenic proteins of the agent. For this study, indirect enzyme-linked immunosorbent assay (ELISA) and immunoblot analyses were performed using pre- and sequential postinoculation sera from M. suis-infected and mock-infected control pigs. M. suis purified from porcine blood served as the antigen. Eight M. suis-specific antigens (p33, p40, p45, p57, p61, p70, p73, and p83) were identified as targets of the immunoglobulin G (IgG) antibody response during experimental infection, with p40, p45, and p70 being the preferentially recognized M. suis antigens. Besides the M. suis-specific antigens, porcine immunoglobulins were identified in blood-derived M. suis preparations. By immunoglobulin depletion, the specificity of the M. suis antigen for use in indirect ELISA was significantly improved. M. suis-specific Western blot and ELISA reactions were observed in all infected pigs by 14 days postinfection at the latest and until week 14, the end of the experiments. During acute clinical attacks of eperythrozoonosis, a derailment of the antibody response, determined by decreases in both the M. suis net ELISA values and the numbers of M. suis-specific immunoblot bands, was accompanied by peaking levels of autoreactive IgG antibodies. In conclusion, the M. suis-specific antigens found to stimulate specific IgG antibodies are potentially useful for the development of novel serodiagnostic tests.

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Menikou, Stephanie, Andrew J. McArdle, Ming-Shi Li, Myrsini Kaforou, Paul R. Langford, and Michael Levin. "A proteomics-based method for identifying antigens within immune complexes." PLOS ONE 15, no. 12 (December 23, 2020): e0244157. http://dx.doi.org/10.1371/journal.pone.0244157.

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A novel approach to recover and identify immune complexes (ICs) was developed using size exclusion chromatography (SEC) and affinity chromatography on immunoglobulin binding columns (HiTrap Protein G). The purification process was monitored by 1D SDS-PAGE, protein staining, Western blotting and, finally, liquid chromatography tandem mass spectrometry (LC MS/MS) was used to identify the recovered antigens. This approach was applied to serum with artificially created immune complexes (ICs) comprising vaccine antigen (influenza) and antibody, which led to recovery and identification of influenza peptides within the recovered ICs. This approach was compared with the established method for IC detection and recovery, polyethylene glycol (PEG) precipitation, followed by LC MS/MS. Both approaches successfully enabled capture, recovery and characterization of immunoglobulins and influenza antigen(s) in complex with the immunoglobulins. However, PEG precipitation has the advantage of simplicity and is more suited for large scale studies.

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Aubert, D., G. T. Maine, I. Villena, J. C. Hunt, L. Howard, M. Sheu, S. Brojanac, L. E. Chovan, S. F. Nowlan, and J. M. Pinon. "Recombinant Antigens To Detect Toxoplasma gondii-Specific Immunoglobulin G and Immunoglobulin M in Human Sera by Enzyme Immunoassay." Journal of Clinical Microbiology 38, no. 3 (2000): 1144–50. http://dx.doi.org/10.1128/jcm.38.3.1144-1150.2000.

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We have evaluated the diagnostic utility of eleven Toxoplasma gondii recombinant antigens (P22 [SAG2], P24 [GRA1], P25, P28 [GRA2], P29 [GRA7], P30 [SAG1], P35, P41 [GRA4], P54 [ROP2], P66 [ROP1], and P68) in immunoglobulin G (IgG) and IgM recombinant enzyme-linked immunosorbent assays (Rec-ELISAs). Following an initial evaluation, six recombinant antigens (P29, P30, P35, P54, P66, and P68) were tested in the IgG and IgM Rec-ELISAs with four groups of samples which span the toxoplasmosis disease spectrum (negative, chronic infection, acute infection, and recent seroconversion). Our results suggest that the combination of P29, P30, and P35 in an IgG Rec-ELISA and the combination of P29, P35, and P66 in an IgM Rec-ELISA can replace the tachyzoite antigen in IgG and IgM serologic tests, respectively. The relative sensitivity, specificity, and agreement for the IgG P29-P30-P35 Rec-ELISA were 98.4, 95.7, and 97.2%, respectively. The resolved sensitivity, specificity, and agreement for the IgM P29-P35-P66 Rec-ELISA were 93.1, 95.0, and 94.5%, respectively. Relative to the tachyzoite-based immunocapture IgM assay, the IgM P29-P35-P66 Rec-ELISA detects fewer samples that contain IgG antibodies with elevated avidity from individuals with an acute toxoplasmosis.

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Maddison, S. E. "Serodiagnosis of parasitic diseases." Clinical Microbiology Reviews 4, no. 4 (October 1991): 457–69. http://dx.doi.org/10.1128/cmr.4.4.457.

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In this review on serodiagnosis of parasitic diseases, antibody detection, antigen detection, use of monoclonal antibodies in parasitic serodiagnosis, molecular biological technology, and skin tests are discussed. The focus at the Centers for Disease Control on developing improved antigens, a truly quantitative FAST-enzyme-linked immunosorbent assay, and the very specific immunoblot assays for antibody detection is highlighted. The last two assays are suitable for field studies. Identification of patient response in terms of immunoglobulin class or immunoglobulin G subclass isotypes or both is discussed. Immunoglobulin isotypes may asist in defining the stage of some diseases. In other instances, use of a particular anti-isotype conjugate may increase the specificity of the assay. Monoclonal antibodies have played important roles in antigen purification and identification, in competitive antibody assays with increased sensitivity and specificity, and in assays for antigen detection in serum, body fluids, or excreta. Molecular biological technology has allowed significant advances in the production of defined parasitic serodiagnostic antigens.

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Priest, Jeffrey W., Delynn M. Moss, Kimberly Won, Charles W. Todd, Leslie Henderson, Cara C. Jones, and Marianna Wilson. "Multiplex Assay Detection of Immunoglobulin G Antibodies That Recognize Babesia microti Antigens." Clinical and Vaccine Immunology 19, no. 9 (August 1, 2012): 1539–48. http://dx.doi.org/10.1128/cvi.00313-12.

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ABSTRACTHuman babesiosis, a blood-borne infection caused by several species ofBabesia, includingB. microti, is an emerging disease that is endemic in the Northeast, upper Midwest, and Pacific Northwest regions of the United States. Risk factors for babesiosis include exposure to the infected tick vector and blood transfusions from infected donors. In this work, we cloned and expressed two of the immunodominant antigens fromB. microtiand used them in a multiplex bead format assay (MBA) to detect parasite-specific IgG responses in human sera. The MBA using recombinantB. microtisecreted antigen 1 (BmSA1) protein was more specific (100%) and slightly more sensitive (98.7%) than the assay using a truncated recombinant BMN1-17 construct (97.6% and 97.4%, respectively). Although some antibody reactivity was observed among sera from confirmed-malaria patients, only onePlasmodium falciparumsample was simultaneously positive for IgG antibodies to both antigens. Neither antigen reacted with sera from babesiosis patients who were infected withBabesiaspecies other thanB. microti. Both positive and negative MBA results were reproducible between assays and between instruments. Additional studies of these recombinant antigens and of the multiplex bead assay using blood samples from clinically defined babesiosis patients and from blood donors are needed to more clearly define their usefulness as a blood screening assay.

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Priest, Jeffrey W., James P. Kwon, Delynn M. Moss, Jacquelin M. Roberts, Michael J. Arrowood, Mark S. Dworkin, Dennis D. Juranek, and Patrick J. Lammie. "Detection by Enzyme Immunoassay of Serum Immunoglobulin G Antibodies That Recognize SpecificCryptosporidium parvum Antigens." Journal of Clinical Microbiology 37, no. 5 (1999): 1385–92. http://dx.doi.org/10.1128/jcm.37.5.1385-1392.1999.

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Human infection with Cryptosporidium parvum usually elicits characteristic immunoglobulin G (IgG), IgA, and IgM antibody responses against two sporozoite surface antigens with apparent molecular masses of approximately 27 and 17 kDa. We have determined that these two antigens are actually complex families of related antigens. We have developed two new enzyme-linked immunosorbent assays (ELISAs) for the detection and quantitation of serum IgG antibodies against both antigens. The assays utilize a recombinant form of the 27-kDa antigen and a partially purified native fraction isolated from sonicated whole oocysts that contains 17-kDa antigen. An immunoblot assay previously developed in our laboratory served as the reference, or “gold standard,” seroassay for the assessment of the new ELISAs. Positive responses with the recombinant-27-kDa-antigen ELISA were correlated with the immunoblot results for the 27-kDa antigen, with a sensitivity and specificity of 90 and 92%, respectively. Similarly, positive responses with the partially purified native-17-kDa-antigen ELISA correlated with the immunoblot results for the 17-kDa antigen, with a sensitivity and specificity of 90 and 94%, respectively. For both ELISAs the median IgG antibody levels for serum sets collected during outbreaks of waterborne C. parvum infection were at least 2.5-fold higher than the levels determined for a nonoutbreak set. Using the immunoblot as the “gold standard,” the new ELISAs were more specific and, in the case of the 27-kDa-antigen ELISA, more sensitive than the crude oocyst antigen ELISA currently in use. These assays will be useful in future epidemiologic studies.

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Mardanly, S. G., A. S. Avdonina, and V. V. Pomazanov. "DEVELOPMENT OF A SET OF REAGENTS FOR DETECTION OF CLASS G IMMUNOGLOBULINS TO THE HUMAN HERPES VIRUS TYPE 7 BY THE METHOD OF IMMUNE BLOTTING IN THE FORMAT «WESTERN BLOT»." Russian Clinical Laboratory Diagnostics 65, no. 6 (May 15, 2020): 362–67. http://dx.doi.org/10.18821/0869-2084-2020-65-6-362-367.

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A new original domestic set of reagents has been developed for the determination of class G immunoglobulins to individual human herpes virus antigens of type 7 by the method of immune blotting in the “Western-blot” format. Preliminary clinical trials were conducted using 134 serums of healthy children aged 1-16 years who underwent diagnostic testing. Study of diagnostic efficiency of the new kit showed high sensitivity, comparable to the sensitivity of the reaction indirect immunofluorescence and high specificity, which is manifested in the absence of false positive results when testing samples containing immunoglobulin G to herpes virus 6 type.

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Tongren, J. Eric, Christopher J. Drakeley, Suzanna L. R. McDonald, Hugh G. Reyburn, Alphaxard Manjurano, Watoky M. M. Nkya, Martha M. Lemnge, et al. "Target Antigen, Age, and Duration of Antigen Exposure Independently Regulate Immunoglobulin G Subclass Switching in Malaria." Infection and Immunity 74, no. 1 (January 2006): 257–64. http://dx.doi.org/10.1128/iai.74.1.257-264.2006.

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ABSTRACT The isotype/subclass of immunoglobulin determines antibody function, but rather little is known about factors that direct class switching in vivo. To evaluate factors that might influence the maturation of the antibody response during infection, we conducted a seroepidemiological study of the immunoglobulin G (IgG) subclass response to four merozoite-associated antigens of Plasmodium falciparum in a mountainous region of northeastern Tanzania, where malaria endemicity declines with increasing altitudes. We found that IgG1/IgG3 class switching is independently affected by the nature of the antigen, cumulative exposure to the antigen, and the maturity of the immune system (i.e., the age of the individual). These observations provide insights into the effects of immune system maturity, the duration and intensity of antigen exposure, and inherent characteristics of individual antigens on the process of class switching in human B cells. Our data also throw light on the consequences of class switch decisions on the gradual acquisition of antimalarial immunity.

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Bobik, Tatiana V., N. N. Kostin, G. A. Scriabin, P. N. Tsabai, M. A. Simonova, Vera D. Knorre, O. N. Stratienko, et al. "COVID-19 in Russia: Clinical and Immunological Features of the First-Wave Patients." Acta Naturae 13, no. 1 (March 15, 2021): 102–15. http://dx.doi.org/10.32607/actanaturae.11374.

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The coronavirus disease outbreak in 2019 (COVID-19) has now achieved the level of a global pandemic and affected more than 100 million people on all five continents and caused over 2 million deaths. Russia is, needless to say, among the countries affected by SARS-CoV-2, and its health authorities have mobilized significant efforts and resources to fight the disease. The paper presents the result of a functional analysis of 155 patients in the Moscow Region who were examined at the Central Clinical Hospital of the Russian Academy of Sciences during the first wave of the pandemic (FebruaryJuly, 2020). The inclusion criteria were a positive PCR test and typical, computed tomographic findings of viral pneumonia in the form of ground-glass opacities. A clinical correlation analysis was performed in four groups of patients: (1) those who were not on mechanical ventilation, (2) those who were on mechanical ventilation, and (3) those who subsequently recovered or (4) died. The correlation analysis also considered confounding comorbidities (diabetes, metabolic syndrome, hypertension, etc.). The immunological status of the patients was examined (levels of immunoglobulins of the M, A, G classes and their subclasses, as well as the total immunoglobulin level) using an original SARS-CoV-2 antibody ELISA kit. The ELISA kit was developed using linear S-protein RBD-SD1 and NTD fragments, as well as the N-protein, as antigens. These antigens were produced in the prokaryotic E. coli system. Recombinant RBD produced in the eukaryotic CHO system (RBD CHO) was used as an antigen representing conformational RBD epitopes. The immunoglobulin A level was found to be the earliest serological criterion for the development of a SARS-CoV-2 infection and it yielded the best sensitivity and diagnostic significance of ELISA compared to that of class M immunoglobulin. We demonstrated that the seroconversion rate of early N-protein-specific IgM and IgA antibodies is comparable to that of antibodies specific to RBD conformational epitopes. At the same time, seroconversion of SARS-CoV-2 N-protein-specific class G immunoglobulins was significantly faster compared to that of other specific antibodies. Our findings suggest that the strong immunogenicity of the RBD fragment is for the most part associated with its conformational epitopes, while the linear RBD and NTD epitopes have the least immunogenicity. An analysis of the occurrence rate of SARS-CoV-2-specific immunoglobulins of different classes revealed that RBD- and N-specific antibodies should be evaluated in parallel to improve the sensitivity of ELISA. An analysis of the immunoglobulin subclass distribution in sera of seropositive patients revealed uniform induction of N-protein-specific IgG subclasses G1G4 and IgA subclasses A1A2 in groups of patients with varying severity of COVID-19. In the case of the S-protein, G1, G3, and A1 were the main subclasses of antibodies involved in the immune response.

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Figueroa, G., G. Faúndez, M. Troncoso, P. Navarrete, and M. S. Toledo. "Immunoglobulin G Antibody Response to Infection with Coccoid Forms of Helicobacter pylori." Clinical and Vaccine Immunology 9, no. 5 (September 2002): 1067–71. http://dx.doi.org/10.1128/cdli.9.5.1067-1071.2002.

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ABSTRACT An increasing number of studies support a potential role for coccoid forms in Helicobacter pylori infection. Evidence for this was obtained through scanning microscopy, genetic analysis for virulence traits, examination of the presence and activity of key enzymes, and other methods. We studied the serum immunoglobulin G responses to coccoid H. pylori forms by enzyme-linked immunosorbent assay (ELISA) and immunoblotting and compared them with those of bacillary cells. Sera from a total of 295 infected individuals were studied; these included sera from 100 patients with duodenal ulcers, 98 patients with nonulcer dyspepsia, 11 patients with gastroduodenal cancer, and 86 asymptomatic individuals. Initially, we characterized and selected coccoid and bacillary antigenic preparations by one-dimensional (1-D) and 2-D gel electrophoresis and immunoblotting. Data showed that coccoid and bacillary preparations with comparable protein contents have similar patterns in 1-D and 2-D electrophoresis gels and antigenic recognition at blotting. These results revealed that coccoid and spiral antigens in ELISA can equally recognize specific antibodies to H. pylori in sera from infected individuals. The analysis of the spiral and coccoid preparations by Western blotting showed no major differences in antigen recognition. No specific bands or profiles associated with a single gastric condition were identified.

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Høglund, Rune Alexander, Silje Bøen Torsetnes, Andreas Lossius, Bjarne Bogen, E. Jane Homan, Robert Bremel, and Trygve Holmøy. "Human Cysteine Cathepsins Degrade Immunoglobulin G In Vitro in a Predictable Manner." International Journal of Molecular Sciences 20, no. 19 (September 29, 2019): 4843. http://dx.doi.org/10.3390/ijms20194843.

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Cysteine cathepsins are critical components of the adaptive immune system involved in the generation of epitopes for presentation on human leukocyte antigen (HLA) molecules and have been implicated in degradation of autoantigens. Immunoglobulin variable regions with somatic mutations and random complementarity region 3 amino acid composition are inherently immunogenic. T cell reactivity towards immunoglobulin variable regions has been investigated in relation to specific diseases, as well as reactivity to therapeutic monoclonal antibodies. Yet, how the immunoglobulins, or the B cell receptors, are processed in endolysosomal compartments of professional antigen presenting cells has not been described in detail. Here we present in silico and in vitro experimental evidence suggesting that cysteine cathepsins S, L and B may have important roles in generating peptides fitting HLA class II molecules, capable of being presented to T cells, from monoclonal antibodies as well as from central nervous system proteins including a well described autoantigen. By combining neural net models with in vitro proteomics experiments, we further suggest how such degradation can be predicted, how it fits with available cellular models, and that it is immunoglobulin heavy chain variable family dependent. These findings are relevant for biotherapeutic drug design as well as to understand disease development. We also suggest how these tools can be improved, including improved machine learning methodology.

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Anderson, Amy L., Romeo Sporici, John Lambris, David LaRosa, and Arnold I. Levinson. "Pathogenesis of B-Cell Superantigen-Induced Immune Complex-Mediated Inflammation." Infection and Immunity 74, no. 2 (February 2006): 1196–203. http://dx.doi.org/10.1128/iai.74.2.1196-1203.2006.

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ABSTRACT Staphylococcal protein A (SpA) is representative of a new class of antigens, the B-cell superantigens (SAgs). These antigens bind to the Fab regions of immunoglobulin molecules outside their complementarity-determining regions. SpA, the best-studied B-cell SAg, reacts with the Fabs of most VH3+ immunoglobulins, which are expressed on 30 to 60% of human peripheral B cells. Therefore, B-cell SAgs like SpA have great potential to elicit inflammatory responses in vivo. We previously reported that the interaction of SpA with VH3+ immunoglobulin molecules leads to activation of the complement cascade and produces a histologic pattern of inflammation in the skin of a rabbit indicative of immune complex injury. To elucidate the cellular and molecular events contributing to this type of unconventional immune complex-mediated inflammation, we established a mouse peritoneal Arthus reaction model. Mice treated intravenously with human polyclonal immunoglobulin G (IgG), followed by intraperitoneal injection of SpA, showed neutrophil influx into the peritoneal cavity with peak numbers appearing at 8 h. This inflammatory reaction was dependent on the interaction of SpA with VH3+ IgG. Mast cells, FcγRIII, complement components, and tumor necrosis factor alpha play obligatory roles, and the reaction is associated with the local release of the CXC chemokines macrophage inflammatory protein 2 and KC. The data provide further compelling evidence for the induction of immune complex-mediated injury by a B-cell SAg and highlight important factors contributing to the pathogenesis of this novel type of inflammatory reaction.

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Bolad, A., S. E. Farouk, E. Israelsson, A. Dolo, O. K. Doumbo, I. Nebie, B. Maiga, et al. "Distinct Interethnic Differences in Immunoglobulin G Class/Subclass and Immunoglobulin M Antibody Responses to Malaria Antigens but not in Immunoglobulin G Responses to Nonmalarial Antigens in Sympatric Tribes Living in West Africa." Scandinavian Journal of Immunology 61, no. 4 (April 2005): 380–86. http://dx.doi.org/10.1111/j.1365-3083.2005.01587.x.

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21

Lü, F. Xusheng, Zhongmin Ma, Tracy Rourke, Seema Srinivasan, Michael McChesney, and Christopher J. Miller. "Immunoglobulin Concentrations and Antigen-Specific Antibody Levels in Cervicovaginal Lavages of Rhesus Macaques Are Influenced by the Stage of the Menstrual Cycle." Infection and Immunity 67, no. 12 (December 1, 1999): 6321–28. http://dx.doi.org/10.1128/iai.67.12.6321-6328.1999.

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ABSTRACT The levels of antigen-specific antibodies (Abs) and immunoglobulins in the cervical mucus of women vary with the menstrual cycle; the highest levels occur during menses, and the lowest occur during the periovulatory period. The rhesus macaque is a widely used animal model of female genital tract immunity. We sought to determine whether rhesus macaques have a cyclical pattern of changing cervicovaginal Ab and immunoglobulin levels that is similar to that of the human female. This study examined the relationship of the stages of the menstrual cycle to genital mucosal and systemic immunoglobulin concentrations and Ab levels in rhesus macaques. In all seven rhesus macaques studied, the immunoglobulins G and A and some antibodies in cervicovaginal lavages varied with the stages of the menstrual cycle, and in many cases this variation reached the level of statistical significance. In a pattern similar to that of women, the highest levels of Abs and immunoglobulins occurred during menses, and the lowest levels occurred around the time of ovulation. However, the Ab and immunoglobulin levels in serum and rectal lavages did not change with the menstrual cycle stage. The results of this study are consistent with the hypothesis that the ovarian hormones that drive the menstrual cycle influence genital tract immunity in female primates.

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Miller, A., H. Sikorska, M. Salvi, and J. R. Wall. "Evaluation of an enzyme-linked immunosorbent assay for the measurement of autoantibodies against eye muscle membrane antigens in Graves' ophthalmopathy." Acta Endocrinologica 113, no. 4 (December 1986): 514–22. http://dx.doi.org/10.1530/acta.0.1130514.

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Abstract. We have tested for antibodies against human and pig eye muscle membrane antigens in the serum of patients with Graves' ophthalmopathy using an enzyme-linked immunosorbent assay (ELISA). Several different membrane preparations were used as source of putative antigen including a 100 000 × g pellet, a pellet depleted of the 100 000 × g (microsome) fraction, and solubilized membranes. With eye muscle membrane pellets there were no significant differences for either serum or immunoglobulins between patients with ophthalmopathy, those with autoimmune thyroid disorders without eye disease, and normal subjects for either human or pig membranes, although tests were positive determined from the upper limit of normal in a few patients with or without eye disease. This was the case regardless of the enzyme-antibody conjugate used, the membrane protein concentration or serum or immunoglobulin dilution. Pre-absorption of tissue fractions, serum, or immunoglobulins, with red blood cells or liver powder, eye muscle membranes or skeletal muscle membranes did not significantly reduce background binding which was often very high, or enhance the difference between patients with ophthalmopathy and normal subjects. It was found that non-specific binding to the plastic surface of the microplates and/or tissue proteins, the presence, in human tissues, of blood-derived immunoglobulins which gave strong reactions in the ELISA, and variable fixation of membrane pellets to the plates were factors which made ELISA unsatisfactory when crude membrane pellets were used as antigen. When eye muscle membranes solubilized with standard agents including SDS, Triton X-100 and deoxycholine were tested, again no differences were demonstrated between patients with Graves' ophthalmopathy and normal subjects. However, when membranes were solubilized with the zwitterionic agent 'CHAPSO' approximately 20% of patients with Graves' ophthalmopathy and smaller proportions of patients with thyroid disease without apparent eye involvement had positive tests with both human and pig eye muscle. While availability of human monoclonal antibodies should soon allow the isolation and purification of soluble eye muscle membrane autoantigens for use in sensitive and specific antibody tests, the ELISA, as presently used with crude tissue fractions, appears too variable and prone to non-specific immunoglobulin-binding for routine clinical use.

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Hur, Yun-Gyoung, Ahreum Kim, Young Ae Kang, An Sik Kim, Dae Yeon Kim, Yeun Kim, Youngmi Kim, Hyeyoung Lee, and Sang-Nae Cho. "Evaluation of Antigen-Specific Immunoglobulin G Responses in Pulmonary Tuberculosis Patients and Contacts." Journal of Clinical Microbiology 53, no. 3 (January 14, 2015): 904–9. http://dx.doi.org/10.1128/jcm.03050-14.

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This study aimed to evaluate the serodiagnostic potential of immunoglobulin G (IgG) responses toMycobacterium tuberculosisantigens in pulmonary tuberculosis (TB) patients, recent TB contacts with latent TB infection (LTBI), and healthy subjects. Infections were assessed using tuberculin skin tests, QuantiFERON-TB Gold In-Tube tests, drug susceptibility testing, and molecular genotyping of clinical isolates. Serum IgG responses to selectiveM. tuberculosisantigens, including the 38-kDa and 16-kDa antigens, lipoarabinomannan (LAM), and recombinant early secreted antigen target 6 kDa (ESAT-6) and culture filtrate protein 10 kDa (CFP-10), were determined. We found that the serum IgG responses to all antigens might differentiate between active TB and LTBI, with LAM having the highest diagnostic value (area under the curve [AUC] of 0.7756,P< 0.001). Recurrent TB cases showed significantly higher IgG responses to 38 kDa, CFP-10 (P< 0.01), and LAM (P< 0.05) than new cases, and male patients had higher levels of antigen-specific IgG than females (P< 0.05). Conversely, drug resistance and patient body mass index did not affect IgG responses (P> 0.05). LAM-specific IgG responses differentiated between acid-fast bacillus (AFB) smear-positive and -negative patients (P< 0.01), whereas antigen-specific IgG responses did not vary with theM. tuberculosisgenotype (P> 0.05). Significantly higher IgG responses to 38 kDa and 16 kDa were observed in AFB smear-negative patients than in controls. These results suggest that assessment of serum IgG responses to selective purifiedM. tuberculosisantigens may help improve the diagnosis of active TB, particularly for sputum smear-negative patients or recurrent cases, and these may also help to differentiate between active TB and LTBI.

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Nally, Jarlath E., Richard L. Hornsby, and David P. Alt. "Antigen-Specific Urinary Immunoglobulin in Reservoir Hosts of Leptospirosis." Veterinary Sciences 8, no. 9 (September 1, 2021): 178. http://dx.doi.org/10.3390/vetsci8090178.

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Domestic and wildlife animal species act as reservoir hosts of leptospirosis, a global zoonotic disease affecting more than 1 million people annually and causing significant morbidity and mortality in domestic animals. In contrast to incidental hosts which present with an array of clinical manifestations, reservoir hosts are typically asymptomatic and can shed leptospires from chronically infected kidneys via urine for extended periods of time. Renal excretion of leptospires occurs despite evidence of a humoral and cellular immune response and is reflective of the unique biological equilibrium that exists between certain animal species and specific serovars of Leptospira. Here, we demonstrate that urinary excretion of leptospires is accompanied by the presence of antigen-specific urinary immunoglobulin. In rats experimentally infected with L. interrogans serovar Copenhageni using the intraperitoneal or conjunctival route of inoculation, urinary immunoglobulin (Ig) G specific for protein antigens was detectable within 1 week. Rat urinary IgG was not bound to urinary-derived leptospires. In cattle that were naturally exposed to, and infected with, L. borgpetersenii serovar Hardjo, urinary IgA specific for protein antigens was detected. Collectively, these results demonstrate that urinary excretion of immunoglobulin specific for leptospires is a hallmark of reservoir hosts of infection.

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Hegarty, Barbara C., Michael G. Levy, Robin F. Gager, and Edward B. Breitschwerdt. "Immunoblot Analysis of the Immunoglobulin G Response to Ehrlichia Canis in Dogs: An International Survey." Journal of Veterinary Diagnostic Investigation 9, no. 1 (January 1997): 32–38. http://dx.doi.org/10.1177/104063879700900106.

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Historically, considerable variation has been reported in the type and severity of clinical and hematologic abnormalities associated with canine ehrlichiosis. Because of difficulties associated with the isolation of intracellular monocytic Ehrlichia species in tissue culture systems, few E. canis isolates are available for comparative microbiologic studies. To address the issue of potential E. canis antigenic diversity in different regions of the world, dog sera reactive by indirect fluorescent antibody testing to E. canis (Florida) antigen were obtained from France, Israel, Italy, the United States, the Virgin Islands, and Zimbabwe. Ehrlichia canis proteins were separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, and at least 5 sera from each region were stained by western immunoblotting. Antibody immunodominance was scored based upon staining intensity. There was relative homogeneity in the immunogenic protein reactions to E. canis antigens. Of the 58 E. canis reactive sera, 54 samples resulted in immunoblot patterns indicative of chronic ehrlichiosis. Four reactive sera (reciprocal titers of 160–2,560) did not recognize any genus-specific antigens resulting in protein bands between 22 and 29 kD, indicating serologic cross-reactivity with other microorganisms. Relatively homogenous immunoblot patterns, consistent with the reported immunoblot response of dogs with experimental chronic ehrlichiosis, were observed with sera from Arizona, France, Israel, North Carolina, Texas, and the Virgin Islands. In contrast, unique major proteins were observed in dog sera from Italy and Zimbabwe. Our results indicate that although relatively homogeneous, antigenic diversity may exist among E. canis organisms in different regions of the world.

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Haghdoost, Mehdi, Parisa Alizadeh Nazmi, and Hamid Owaysee Osquee. "Diagnostic value of serum IgG by Eliza to detecting Mycobacterium tuberculosis, Original Article." Journal of Research in Clinical Medicine 9, no. 1 (July 24, 2021): 29. http://dx.doi.org/10.34172/jrcm.2021.029.

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Introduction: In developing countries, which is an endemic region in terms of tuberculosis, there is an urgent need for fast, accurate, and inexpensive serological testing. The aim of this study was to determine the diagnostic value of patient serum IgG antibodies by ELISA in the diagnosis of Mycobacterium tuberculosis. Method: This case-control study was performed on patients with pulmonary tuberculosis in 2017-2020. After selecting the case (n = 30) and control (n = 30) subjects according to inclusion criteria, their blood samples were obtained and analyzed in the reference laboratory by standard kits for immunoglobulin G against 16, 36, and 40 kDa antigens of mycobacterium tuberculosis. Results: The mean age of the subjects was 47.07 (15.57%). The majority of participants were 46 (51.1%) women. There was no significant difference between the two groups regarding sex and age. serological examination of patients with pulmonary tuberculosis showed 25 positive results and only 4 of the control group had a positive result. Sensitivity, specificity, positive and negative predictive values of serology test were 83.3%, 86.67%, 86.20% and 87.88% respectively. Conclusion: Despite the acceptable sensitivity of the serologic immunoglobulin G test, according to the statement of World health organization (WHO), it did not possess an acceptable specificity. It is recommended that a a wider range of different antigens to be studied also it is essential to evaluate the diagnostic value of the other immunoglobulins inpatient in different stages of the disease.

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El Namaky, A. H., S. H. Hendawy, F. A. Abo-Aziza, and H. M. Ashry. "Cytokines and immunoglobulin g response in donkeys with spontaneous Setaria equine infection." BULGARIAN JOURNAL OF VETERINARY MEDICINE 22, no. 2 (2019): 180–89. http://dx.doi.org/10.15547/bjvm.2049.

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Setaria equina (S. equina) is a filarial worm that exists in peritoneal cavity of equines. This study aimed to evaluate cytokine mediators tumour necrosis factor alpha (TNF-α), interleukin-4 (IL-4) and immunoglobulin G (IgG) responses in spontaneously S. equina infected and non-infected donkeys with emphasis on choosing the best antigen that could be used in diagnosis of such filarial infection. A total of 87 donkeys were examined. Two S. equina antigens: crude somatic S. equina antigen (CSS) and excretory secretory S. equina antigen (ESS) were prepared. They were evaluated in diagnosis of the infection using indirect ELISA and electrophoretically characterised through sodium dodecyl sulphate poly acrylamide gel electrophoresis (SDS-PAGE) and western blotting technique. The results indicated that both TNF-α and IL-4 in the serum of infected donkeys were significantly higher compared with the non-infected group at P<0.05 and P<0.01, respectively. However, the IL-4 level of infected donkeys was significantly higher than that of TNF-a (P<0.01). Apparent prevalence, specificity and positive predictive values (96.55%, 100%, and 100% each) of CSS showed higher diagnostic accuracy than that of ESS. In addition, electrophoretic protein profile and IgG reactivity of CSS antigen via western blot presented a prominent reactive protein band at 28 kDa. It was concluded that the CSS antigen was the best antigen that could be used in serodiagnosis of S. equina infection. The cytokine responses were explored in order to differentiate infected from non-infected donkeys.

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Priest, Jeffrey W., Delynn M. Moss, Govinda S. Visvesvara, Cara C. Jones, Anna Li, and Judith L. Isaac-Renton. "Multiplex Assay Detection of Immunoglobulin G Antibodies That Recognize Giardia intestinalis and Cryptosporidium parvum Antigens." Clinical and Vaccine Immunology 17, no. 11 (September 28, 2010): 1695–707. http://dx.doi.org/10.1128/cvi.00160-10.

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ABSTRACT Giardiasis and cryptosporidiosis are common enteric parasitic diseases that have similar routes of transmission. In this work, we have identified epitopes within the Giardia variant-specific surface protein (VSP) sequences that are recognized by IgG antibodies from 13 of 14 (93%) sera from patients with stool-confirmed giardiasis. The conserved epitopes are shared among VSPs from both of the assemblages that commonly infect humans, and they are likely to be structural, as both sodium dodecyl sulfate treatment and dithiothreitol reduction decrease antibody recognition. In a multiplex bead assay (MBA), we used three VSP fragments from an assemblage A Giardia strain, three VSP fragments from assemblage B strains, and the α-1 giardin structural antigen to detect IgG antibodies to Giardia and used the recombinant 17- and 27-kDa antigens to simultaneously detect IgG antibodies to Cryptosporidium. The MBA differentiated between sera from Giardia and Cryptosporidium outbreaks and also identified a giardiasis outbreak that may have included cryptosporidiosis cases. Approximately 40% of cryptosporidiosis outbreak samples had high MBA responses for both the 27- and 17-kDa antigens, while <10% of nonoutbreak and giardiasis outbreak samples had high responses. At least 60% of giardiasis outbreak samples were positive for antibodies to multiple Giardia antigens, while ≤12% of nonoutbreak samples and samples from U.S. and British Columbia cryptosporidiosis outbreaks met our definition for Giardia seropositivity. A MBA using multiple parasite antigens may prove useful in the epidemiologic analysis of future waterborne or food-borne outbreaks of diarrheal disease.

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Dos Santos, Flavia B., Rita Maria R. Nogueira, Monique R. Q. Lima, Thatiane S. De Simone, Hermann G. Schatzmayr, Elezer M. B. Lemes, Eva Harris, and Marize P. Miagostovich. "Recombinant Polypeptide Antigen-Based Immunoglobulin G Enzyme-Linked Immunosorbent Assay for Serodiagnosis of Dengue." Clinical and Vaccine Immunology 14, no. 5 (March 28, 2007): 641–43. http://dx.doi.org/10.1128/cvi.00474-06.

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ABSTRACT We have developed an indirect enzyme-linked immunosorbent assay for detection of anti-dengue virus (DENV) immunoglobulin G antibodies using four recombinant DENV envelope polypeptides as antigens, which demonstrated a sensitivity of 89.4% and a specificity of 93.3%. These easily produced antigens are a feasible, cost-effective alternative for generating reagents for dengue serological tests.

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Craig, Vanessa J., Isabelle Arnold, Christiane Gerke, Minh Q. Huynh, Thomas Wündisch, Andreas Neubauer, Christoph Renner, Stanley Falkow, and Anne Müller. "Gastric MALT lymphoma B cells express polyreactive, somatically mutated immunoglobulins." Blood 115, no. 3 (January 21, 2010): 581–91. http://dx.doi.org/10.1182/blood-2009-06-228015.

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Abstract Gastric B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) arises against a background of chronic inflammation caused by persistent Helicobacter pylori infection. The clinical and histopathologic features of the human tumor can be reproduced by Helicobacter infection of BALB/c mice. In this study, we have analyzed the antibody sequences and antigen specificity of a panel of murine and human MALT lymphoma–derived antibodies. We find that a majority of tumors in patients as well as experimentally infected mice are monoclonal. The tumor immunoglobulin heavy chain genes have undergone somatic hypermutation, and approximately half of all tumors show evidence of intraclonal variation and positive and/or negative selective pressure. Recombinantly expressed MALT lymphoma antibodies bind with intermediate affinity to various unrelated self- and foreign antigens, including Helicobacter sonicate, immunoglobulin G (IgG), DNA, and stomach extract; antigen binding is blocked in a dose-dependent manner in competitive enzyme-linked immunosorbent assays. A strong bias toward the use of VH gene segments previously linked to autoantibodies and/or polyreactive antibodies in B-cell malignancies or autoimmune pathologies supports the experimental finding of polyreactivity. Our results suggest that MALT lymphoma development may be facilitated by an array of local self- and foreign antigens, providing direct antigenic stimulation of the tumor cells via their B-cell receptor.

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Aparecida de Carvalho, Camila, Roberto Mitsuyoshi Hiramoto, Luciana Regina Meireles, and Heitor Franco de Andrade Júnior. "Serum antibodies blocked by glycan antigens in canine visceral leishmaniasis serology are mostly IgA immune complexes." Parasitology 148, no. 12 (July 5, 2021): 1509–15. http://dx.doi.org/10.1017/s0031182021001189.

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AbstractImmune complexes (ICs) are found in canine visceral leishmaniasis (CVL) and interfere with the serum detection of antibodies. Dissociation of these monovalent complexes by dissociative enzyme-linked immunosorbent assay (ELISA) removes false-negative results and allows some characterization of antibodies and antigens. We studied the serology of dogs with suspected CVL in an endemic area, testing two Leishmania (Leishmania) [L. (L.)] <full form>infantum antigens. We analysed the presence of immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM) antibodies specific to promastigote soluble extract (PSE) and low-molecular weight glycans (glycan–bovine serum albumin (BSA) complex – GBC) by conventional and dissociative ELISA. Our results showed a significant fraction of IgA ICs (46.5% for PSE and 47.6% for GBC), followed by IgG ICs (10% for PSE and 23.5% for GBC). IgM ICs were more frequent for PSE (22.7%). Hypergammaglobulinaemia in CVL would be related to the presence of IgA and IgG ICs, resulting in deficient elimination of these antibodies. Our data confirmed the presence of ICs that can generate false-negative results in conventional serology. The production of IgA antibodies and the high frequency of blockade by glycan antigens suggest the active participation of this immunoglobulin and its ICs in the immunopathology of CVL, indicating a new path for further research.

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Lyashchenko, Konstantin, Roberto Colangeli, Michel Houde, Hamdan Al Jahdali, Dick Menzies, and Maria Laura Gennaro. "Heterogeneous Antibody Responses in Tuberculosis." Infection and Immunity 66, no. 8 (August 1, 1998): 3936–40. http://dx.doi.org/10.1128/iai.66.8.3936-3940.1998.

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ABSTRACT Antibody responses during tuberculosis were analyzed by an enzyme-linked immunosorbent assay with a panel of 10 protein antigens of Mycobacterium tuberculosis. It was shown that serum immunoglobulin G antibodies were produced against a variety of M. tuberculosis antigens and that the vast majority of sera from tuberculosis patients contained antibodies against one or more M. tuberculosis antigens. The number and the species of serologically reactive antigens varied greatly from individual to individual. In a given serum, the level of specific antibodies also varied with the antigen irrespective of the total number of antigens recognized by that particular serum. These findings indicate that person-to-person heterogeneity of antigen recognition, rather than recognition of particular antigens, is a key attribute of the antibody response in tuberculosis.

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Kumagai, T., J. Yan, D. Y. Graham, M. Tozuka, Y. Okimura, T. Ikeno, A. Sugiyama, T. Katsuyama, and H. Ota. "Serum Immunoglobulin G Immune Response to Helicobacter pylori Antigens in Mongolian Gerbils." Journal of Clinical Microbiology 39, no. 4 (April 1, 2001): 1283–88. http://dx.doi.org/10.1128/jcm.39.4.1283-1288.2001.

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34

Huskinson, J., P. N. Stepick-Biek, F. G. Araujo, P. Thulliez, Y. Suzuki, and J. S. Remington. "Toxoplasma antigens recognized by immunoglobulin G subclasses during acute and chronic infection." Journal of Clinical Microbiology 27, no. 9 (1989): 2031–38. http://dx.doi.org/10.1128/jcm.27.9.2031-2038.1989.

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35

Aucan, Christophe, Yves Traoré, Francis Fumoux, and Pascal Rihet. "Familial Correlation of Immunoglobulin G Subclass Responses to Plasmodium falciparum Antigens in Burkina Faso." Infection and Immunity 69, no. 2 (February 1, 2001): 996–1001. http://dx.doi.org/10.1128/iai.69.2.996-1001.2001.

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ABSTRACT Host genes are thought to determine the immune response to malaria infection and the outcome. Cytophilic antibodies have been associated with protection, whereas noncytophilic antibodies against the same epitopes may block the protective activity of the protective ones. To assess the contribution of genetic factors to immunoglobulin G (IgG) subclass responses against conserved epitopes and Plasmodium falciparum blood-stage extracts, we analyzed the isotypic distribution of the IgG responses in 366 individuals living in two differently exposed areas in Burkina Faso. We used one-way analysis of variance and pairwise estimators to calculate sib-sib and parent-offspring correlation coefficients, respectively. Familial patterns of inheritance of IgG subclass responses to defined antigens and P. falciparum extracts appear to be similar in the two areas. We observed a sibling correlation for the IgG, IgG1, IgG2, IgG3, and IgG4 responses directed against ring-infected-erythrocyte surface antigen, merozoite surface protein 1 (MSP-1), MSP-2, andP. falciparum extract. Moreover, a parent-offspring correlation was found for several IgG subclass responses, including the IgG, IgG1, IgG2, IgG3, and IgG4 responses directed against conserved MSP-2 epitopes. Our results indicated that the IgG subclass responses against P. falciparum blood-stage antigens are partly influenced by host genetic factors. The localization and identification of these genes may have implications for immunoepidemiology and vaccine development.

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Amicosante, M., G. Paone, F. Ameglio, EL Bianchi, E. Piccolella, L. Richeldi, A. Bisetti, M. Luisetti, and C. Saltini. "Antibody repertoire against the A60 antigen complex during the course of pulmonary tuberculosis." European Respiratory Journal 6, no. 6 (June 1, 1993): 816–22. http://dx.doi.org/10.1183/09031936.93.06060816.

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The A60 antigen complex is a Mycobacterium bovis (BCG) highly immunodominant antigen containing both B and T-cell epitopes. Clinical-serological studies show that elevated anti-A60 titres are present during tuberculosis. We wished to analyze in detail antibody responses against A60 components during the course of tuberculosis. A mixed longitudinal study was designed including individuals at the onset of tuberculosis, during treatment and after resolution of the disease. The anti-A60 repertoire was analyzed using a western blot assay with A60 as the antigen. While PPD- normals recognized only the 65 kDa heat shock protein (HSP), PPD+ normal individuals displayed low levels of anti-A60 antibodies against dominant antigens. There were immunoglobulin M (IgM) and immunoglobulin G (IgG) consistent with response to a latent infection. Onset tuberculosis was characterized by IgM and IgG antibodies against 52 to 28 kDa antigens; IgM response being limited to earlier phases of the disease. In contrast, IgM antibodies against 25 to 14 kDa antigens appeared only 2-6 months after disease onset. The antibody repertoire of chemotherapy-treated, resolved tuberculosis was exclusively IgG in isotype, as for a memory-type response. Thus, western blot analysis with A60 identifies typical antibody patterns associated with different clinical phases of tuberculosis infection. Such approach may help in identifying new single antigens for serologic diagnosis of active tuberculosis.

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Lee, Yi-Hsin, Kuo-Wang Tsai, Kuo-Cheng Lu, Li-Jane Shih та Wan-Chung Hu. "Cancer as a Dysfunctional Immune Disorder: Pro-Tumor TH1-like Immune Response and Anti-Tumor THαβ Immune Response Based on the Complete Updated Framework of Host Immunological Pathways". Biomedicines 10, № 10 (6 жовтня 2022): 2497. http://dx.doi.org/10.3390/biomedicines10102497.

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Host immunological pathways are delicate to cope with different types of pathogens. In this article, we divide immunological pathways into two groups: Immunoglobulin G-related eradicable immunities and Immunoglobulin A-related tolerable immunities. Once immune cells encounter an antigen, they can become anergic or trigger immune reactions. Immunoglobulin D B cells and gδ T cells are recognizing self-antigens to become anergic. Immunoglobulin M B cells and ab T cells can trigger host immune reactions. Eradicable immune responses can be divided into four groups: TH1/TH2/TH22/THab (TH—T Helper cell groups). Tolerable immune responses can be divided into four groups: TH1-like/TH9/TH17/TH3. Four groups mean hosts can cope with four types of pathogens. Cancer is related to immune dysfunction. TH1-like immunity is pro-tumor immunity and THab is anti-tumor immunity. TH1-like immunity is the host tolerable immunity against intracellular micro-organisms. THab immunity is the host eradicable immunity against viruses. Cancer is also related to clonal anergy by Immunoglobulin D B cells and gδ T cells. Oncolytic viruses are related to the activation of anti-viral THab immunity. M2 macrophages are related to the tolerable TH1-like immunity, and they are related to metastasis. This review is key to understanding the immune pathogenesis of cancer. We can then develop better therapeutic agents to treat cancer.

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38

Obukhanych, Tetyana V., and Michel C. Nussenzweig. "T-independent type II immune responses generate memory B cells." Journal of Experimental Medicine 203, no. 2 (February 13, 2006): 305–10. http://dx.doi.org/10.1084/jem.20052036.

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Unlike T-dependent immune responses against protein antigens, T-independent responses against polysaccharides confer long-lasting humoral immunity in the absence of recall responses and are not known to generate memory B cells. Here we report that polysaccharide antigens elicit memory B cells that are phenotypically distinct from those elicited by protein antigens. Furthermore, memory B cell responses against polysaccharides are regulated by antigen-specific immunoglobulin G antibodies. As the generation and regulation of immunologic memory is central to vaccination, our findings help explain the mode of action of the few existing polysaccharide vaccines and provide a rationale for a wider application of polysaccharide-based strategies in vaccination.

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Pinder, Margaret, Colin J. Sutherland, Fatoumatta Sisay-Joof, Jamila Ismaili, Matthew B. B. McCall, Rosalyn Ord, Rachel Hallett, Anthony A. Holder, and Paul Milligan. "Immunoglobulin G Antibodies to Merozoite Surface Antigens Are Associated with Recovery from Chloroquine-Resistant Plasmodium falciparum in Gambian Children." Infection and Immunity 74, no. 5 (May 2006): 2887–93. http://dx.doi.org/10.1128/iai.74.5.2887-2893.2006.

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ABSTRACT We examined the hypothesis that recovery from uncomplicated malaria in patients carrying drug-resistant Plasmodium falciparum is a measure of acquired functional immunity and may therefore be associated with humoral responses to candidate vaccine antigens. Gambian children with malaria were treated with chloroquine in 28-day trials, and recovery was defined primarily as the absence of severe clinical malaria at any time and absence of parasitemia with fever after 3 days. Plasma samples from these children were assayed by enzyme-linked immunosorbent assay for immunoglobulin G (IgG) to recombinant merozoite antigens: apical membrane antigen 1 (AMA-1) and the 19-kDa C-terminal region of merozoite surface protein 1 (MSP-119), including antigenic variants of MSP-119 with double and triple substitutions. Antigen-specific IgG was more frequent in children who recovered, particularly that for MSP-119 (age-adjusted odds ratios: 0.32 [95% confidence interval, 0.05, 1.87; P = 0.168] for AMA-1, 0.19 [0.03, 1.11; P = 0.019] for recombinant MSP-119, 0.24 [0.04, 1.31; P = 0.032] for the recombinant MSP-119 double variant, and 0.18 [0.03, 0.97; P = 0.013] for the triple variant). IgG titers to MSP-119 and to the triple variant were higher in plasma samples taken 7 days after chloroquine treatment from children who carried resistant parasites but recovered and remained parasite free. Moreover, in children who were parasitemic on day 14 or day 28, there was an age-independent relationship between parasite density and IgG to both MSP-119 and the triple variant (coefficients of −0.550 and −0.590 and P values of 0.002 and 0.001, respectively). The results validate the use of this approach to identify antigens that are associated with protection from malaria.

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40

Andrews, L. P., R. K. Clark, and I. Damjanov. "Mixed glycosidase pretreatment reduces nonspecific binding of antibodies to frozen tissue sections." Journal of Histochemistry & Cytochemistry 33, no. 7 (July 1985): 695–98. http://dx.doi.org/10.1177/33.7.3891844.

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Indirect immunohistochemical studies of frozen mouse tissues with mouse monoclonal antibodies yield, in general, suboptimal results primarily because of indiscriminate binding of secondary antibody to all mouse immunoglobulins, i.e., to the monoclonal reagent and to endogenous immunoglobulin nonspecifically trapped in the tissue. To reduce this nonspecific staining, frozen sections of mouse kidney were treated enzymatically. Optimal results were obtained following a 2 hr treatment with 20 mg/ml of mixed glycosidases (MG). This treatment reduced the nonspecific background staining of the interstitial spaces and blood vessels, but did not affect the reactivity of structurally bound immunoglobulin G (IgG) in the glomeruli or alter the reactivity of mouse renal tissue to the monoclonal antibody that recognizes an oligosaccharide antigenic determinant (SSEA-1). Eluates from enzyme-treated frozen tissue sections contained normally immunoreactive IgG in the form of dimers. These data indicate that MG treatment of frozen sections could be safely used to reduce the content of nonstructurally bound immunoglobulins in frozen tissues and thus improve the visualization of specific monoclonal antibody binding.

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41

Purkall, Donald, John G. Tew, and Harvey A. Schenkein. "Opsonization of Actinobacillus actinomycetemcomitans by Immunoglobulin G Antibody Reactive with Phosphorylcholine." Infection and Immunity 70, no. 11 (November 2002): 6485–88. http://dx.doi.org/10.1128/iai.70.11.6485-6488.2002.

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ABSTRACT We used two strains of Actinobacillus actinomycetemcomitans, one bearing phosphorylcholine (PC) (strain D045D-40) and one devoid of PC antigens (strain DB03A-42), as well as a nonencapsulated strain of Streptococcus pneumoniae (strain 39937), to examine the opsonic properties of physiological concentrations (⩽30 μg/ml) of purified human anti-PC immunoglobulin G (IgG). Anti-PC bound to both A. actinomycetemcomitans DO45D-40 and S. pneumoniae 39937 and induced superoxide anion production by polymorphonuclear neutrophils; induction of the oxidative burst was inhibited by antibodies to either CD16 or CD32. Thus, anti-PC IgG at concentrations present in most human sera promotes the opsonization of PC-expressing strains of A. actinomycetemcomitans in the absence of complement, implying that anti-PC may be a protective antibody against such strains of bacteria.

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42

Gustavsson, Chomez, and Heyman. "Low Responsiveness to Immunization with Immunoglobulin E/Antigen and Immunoglobulin G/Antigen Complexes in H-2Ab Mice." Scandinavian Journal of Immunology 50, no. 1 (July 1999): 45–51. http://dx.doi.org/10.1046/j.1365-3083.1999.00558.x.

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43

Subramaniam, Vijayalakshmi, Vidya Pai, and Mehjooba Roushan Mazumdar. "Effects of adenotonsillectomy on humoral immunity." International Journal of Otorhinolaryngology and Head and Neck Surgery 2, no. 4 (September 26, 2016): 230. http://dx.doi.org/10.18203/issn.2454-5929.ijohns20163471.

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Background: Adenotonsillectomy is one of the commonest surgical procedures performed by the otolaryngologists. The immunological effects of adenotonsillectomy have not been studied extensively. Some researchers have found decreased immunoglobulin levels after adenotonsillectomy while others have not reported any significant changes. The present study aimed to evaluate the changes in humoral immunity in patients undergoing adenotonsillectomy before and after surgery as measured by serum immunoglobulin levels.Methods: The study designed was a prospective observational case-control study conducted at Yenepoya Medical College Hospital, a tertiary referral hospital, Mangalore, Karnataka. A total of 25 patients in the age range 5-15years who underwent adenotonsillectomy for chronic adenotonsillitis and 25 age and sex matched controls participated in the study. Serum immunoglobulin G, A and M (IgG, IgA and IgM) levels were estimated 24 hours prior and 4 weeks after adenotonsillectomy. The statistical analysis used was non-parametric tests.Results: Serum levels of IgG, A and M were found to be significantly higher in patients with chronic adenotonsillitis. The levels of all the three immunoglobulins decreased to normal one month post-operatively.Conclusions: Removal of infected tissue and chronic antigenic stimulation resulted in restoration of serum immunoglobulin levels to normal. While chronic adenotonsillitis contributed to changes in humoral immunity as reflected by higher serum immunoglobulin levels, adenotonsillectomy enabled restoration of the immunoglobulin levels to normal.

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Rossi, CláudioL, and LisandraA Suzuki. "Intrathecal synthesis of immunoglobulin G antibodies to Taenia solium scolex antigens in neurocysticercosis." Neurology India 67, no. 2 (2019): 574. http://dx.doi.org/10.4103/0028-3886.257988.

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45

Schofield, L. "CD1d-Restricted Immunoglobulin G Formation to GPI-Anchored Antigens Mediated by NKT Cells." Science 283, no. 5399 (January 8, 1999): 225–29. http://dx.doi.org/10.1126/science.283.5399.225.

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46

McCool, Tera L., Thomas R. Cate, Elaine I. Tuomanen, Peter Adrian, Tim J. Mitchell, and Jeffrey N. Weiser. "Serum Immunoglobulin G Response to Candidate Vaccine Antigens during Experimental Human Pneumococcal Colonization." Infection and Immunity 71, no. 10 (October 2003): 5724–32. http://dx.doi.org/10.1128/iai.71.10.5724-5732.2003.

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ABSTRACT The immune response to pneumococcal surface structures during colonization was examined in a model of experimental human pneumococcal carriage. Healthy uncolonized adults were given a type 23F or 6B pneumococcus, and a portion of these subjects became colonized (6 of 14 with type 23F and 6 of 8 with type 6B). Sera from colonized and uncolonized subjects were used to determine the titer of antibody specific to pneumococcal surface components under consideration in development of noncapsular polysaccharide-based vaccines. These vaccine candidates included pneumococcal surface protein A (PspA), choline binding protein A (CbpA), lipoteichoic acid, immunoglobulin A1 (IgA1) protease, pneumolysin, proteinase maturation protein A, and pneumococcal surface adhesin A. Only the two related choline binding proteins, PspA and CbpA, were immunogenic in colonized subjects as determined by a statistically significant rise in the serum IgG titer. The serum IgG response to PspA was shown previously to correlate inversely with susceptibility to carriage and was localized to a region within the N-terminal portion of PspA. This region is highly variable in amino acid sequence between pneumococcal strains. Despite the sequence diversity in the immunodominant regions of both PspA and CbpA, a significant strain-to-strain cross-reactivity in the serum IgG response following experimental human carriage was observed. These findings support the need for further investigation of the human antibody response to PspA and CbpA and the potential use of one or both of these proteins as novel vaccine antigens for the prevention of pneumococcal colonization.

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47

Adams, D. S., J. S. McDonald, D. Hancock, and T. C. McGuire. "Staphylococcus aureus antigens reactive with milk immunoglobulin G of naturally infected dairy cows." Journal of Clinical Microbiology 26, no. 6 (1988): 1175–80. http://dx.doi.org/10.1128/jcm.26.6.1175-1180.1988.

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48

Priest, Jeffrey W., Caryn Bern, Lihua Xiao, Jacquelin M. Roberts, James P. Kwon, Andres G. Lescano, William Checkley, et al. "Longitudinal Analysis of Cryptosporidium Species-Specific Immunoglobulin G Antibody Responses in Peruvian Children." Clinical and Vaccine Immunology 13, no. 1 (January 2006): 123–31. http://dx.doi.org/10.1128/cvi.13.1.123-131.2006.

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ABSTRACT Cryptosporidium species are ubiquitous in the environment and are frequently detected in the stools of children who live where sanitation conditions are poor. To better characterize the immune response to these parasites, we monitored immunoglobulin G (IgG) antibody levels in a cohort of children from Lima, Peru. Two new enzyme-linked immunosorbent assays based on the C. parvum (bovine, subtype IIa) Iowa strain 17-kDa and 27-kDa antigens were used to measure IgG antibody levels in longitudinal serum samples. Antibody responses were detected during infections with C. parvum, C. felis, and C. meleagridis and with four different subtypes of C. hominis. We also noted that the magnitude of the antibody response was related to the number of previous infections and that older children generally had higher levels of antibodies to the two C. parvum antigens. Antibody responses were not associated with infections with either Cyclospora sp. or Giardia sp. We believe the antibody assays will be important tools for monitoring the success of future public health interventions.

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Mehta, Anand S., Ronald E. Long, Mary Ann Comunale, Mengjun Wang, Lucy Rodemich, Jonathan Krakover, Ramila Philip, Jorge A. Marrero, Raymond A. Dwek, and Timothy M. Block. "Increased Levels of Galactose-Deficient Anti-Gal Immunoglobulin G in the Sera of Hepatitis C Virus-Infected Individuals with Fibrosis and Cirrhosis." Journal of Virology 82, no. 3 (November 28, 2007): 1259–70. http://dx.doi.org/10.1128/jvi.01600-07.

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ABSTRACT Hepatitis B and C viruses are major causative agents of liver fibrosis, cirrhosis, and liver cancer. Using comparative glycoproteomics, we identified a glycoprotein that is altered both in amount and in glycosylation as a function of liver fibrosis and cirrhosis. Specifically, this altered glycoprotein is an immunoglobulin G (IgG) molecule reactive to the heterophilic alpha-Gal epitope [Galα-1-3Galβ1-(3)4GlcNAc-R]. While similar changes in glycosylation have been observed in several autoimmune diseases, the specific immunoglobulins and their antigen recognition profiles were not determined. Thus, we provide the first report identifying the specific antigenic recognition profile of an immunoglobulin molecule containing altered glycosylation as a function of liver disease. This change in glycosylation allowed increased reactivity with several fucose binding lectins and permitted the development of a plate-based assay to measure this change. Increased lectin reactivity was observed in 100% of the more than 200 individuals with stage III or greater fibrosis and appeared to be correlated with the degree of fibrosis. The reason for the alteration in the glycosylation of anti-Gal IgG is currently unclear but may be related to the natural history of the disease and may be useful in the noninvasive detection of fibrosis and cirrhosis.

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Ippolito, Gregory C., Robert L. Schelonka, Michael Zemlin, Ivaylo I. Ivanov, Ryoki Kobayashi, Cosima Zemlin, G. Larry Gartland, et al. "Forced usage of positively charged amino acids in immunoglobulin CDR-H3 impairs B cell development and antibody production." Journal of Experimental Medicine 203, no. 6 (June 5, 2006): 1567–78. http://dx.doi.org/10.1084/jem.20052217.

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Tyrosine and glycine constitute 40% of complementarity determining region 3 of the immunoglobulin heavy chain (CDR-H3), the center of the classic antigen-binding site. To assess the role of DH RF1-encoded tyrosine and glycine in regulating CDR-H3 content and potentially influencing B cell function, we created mice limited to a single DH encoding asparagine, histidine, and arginines in RF1. Tyrosine and glycine content in CDR-H3 was halved. Bone marrow and spleen mature B cell and peritoneal cavity B-1 cell numbers were also halved, whereas marginal zone B cell numbers increased. Serum immunoglobulin G subclass levels and antibody titers to T-dependent and T-independent antigens all declined. Thus, violation of the conserved preference for tyrosine and glycine in DH RF1 alters CDR-H3 content and impairs B cell development and antibody production.

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