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Other Antigens (other + antigen)
Selected AbstractsBullous pemphigoid antigen II (BP180) and its soluble extracellular domains are major autoantigens in mucous membrane pemphigoid: the pathogenic relevance to HLA class II alleles and disease severityBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2006N. Oyama Summary Background, Mucous membrane pemphigoid (MMP), a chronic autoimmune subepithelial blistering disease, is associated with circulating IgG and/or IgA autoantibodies against several basement membrane zone antigens. The heterogeneity of clinical presentation and diversity of target autoantigens have contributed to difficulties in characterizing this condition immunologically. Objectives, To analyse serum autoantibody profile and HLA class II alleles in MMP patients and to correlate this with the clinical presentation of disease. Methods, Well-defined subgroups consisting of 124 patients with MMP were examined for IgG and IgA reactivity with immunoblotting using human epidermal, dermal and placental amnion proteins. The results were further analysed on the basis of detailed clinical (sites of involvement and disease severity) and immunopathological criteria (immunofluorescence study and HLA class II alleles). Results, Immunoblot assay revealed that the majority of MMP patients had IgG (93 of 124, 75%) and/or IgA autoantibodies (63 of 124, 51%) to BP180 (including its soluble ectodomains, 120-kDa LAD-1 and 97-kDa LABD97 antigens). Other antigens targeted predominantly by IgG autoantibodies included: BP230 in 34 (27%), ,4 integrin in 26 (21%), and laminin 5 in three (2%). All the BP230+ sera and 23 (88%) ,4 integrin+ sera also reacted with at least one of the BP180 antigens. Over 85% of patients with reactivity to ,4 integrin had ocular involvement. In most cases of MMP, more severe clinical features were associated with antibody reactivity to multiple basement membrane zone antigens, as well as reactivity to multiple BP180 component antigens. Dual BP180/LAD-1 reactivity with IgG and IgA was associated with a more severe phenotype. In addition, the subset-dependent autoantibody reactivity correlated well with specific HLA class II alleles, DQB1*0301, DRB1*04 and DRB1*11. Conclusions, Our results confirmed that BP180 is a major autoantigen targeted by the sera of patients with MMP. The disease-prevalent HLA class II alleles and humoral autoimmune response against the particular subsets of antigenic epitope(s) within BP180 ectodomain may contribute to the clinicopathological significance and disease severity of MMP. [source] Clinical utility of CD23 and FMC7 antigen coexistent expression in B-cell lymphoproliferative disorder subclassificationCYTOMETRY, Issue 1 2002Ejaz Ahmad Abstract Background: CD23 and FMC7 are normal B-cell antigens utilized during diagnostic immunophenotyping of suspected lymphoproliferative disorders. However, the diagnostic utility of coexistent antigenic expression patterns with simultaneous two-color staining and flow cytometric analysis has not been studied extensively. Methods: Using multiparameter flow cytometry, we evaluated the expression pattern of FMC7 and CD23 in 218 cases of B-cell lymphoma from blood and bone marrow specimens. Results: The CD23(+)/FMC7(-) pattern was the most common pattern in patients with chronic lymphocytic leukemia and related variants. The widest variation of patterns was found in patients with follicular cell lymphoma, large cell lymphoma, and Waldenström's macroglobulinemia, a lymphoplasmacytoid disorder, although most cases expressed the CD23-/FMC7(+) pattern. The CD23 and FMC7 antigen, along with the CD5 coexpression pattern, provides critical adjunctive data. These data allow accurate classification of the majority of cases, thereby providing a key aspect of a reliable diagnostic algorithm. The CD23 and FMC7 antigen expression pattern, along with selected other antigens, was predictive of subtypes in >95% of lymphoproliferative cases and narrowed the differential diagnosis in the remaining cases. Conclusion: The flow cytometric CD23/FMC7 expression pattern achieved by multicolor immunophenotyping facilitates accurate and reproducible classification of B-cell lymphomas and has diagnostic utility. Cytometry (Clin. Cytometry) 50:1,7, 2002. © 2002 Wiley-Liss, Inc. [source] Vaccines modulating lipoprotein autoimmunity as a possible future therapy for cardiovascular diseaseJOURNAL OF INTERNAL MEDICINE, Issue 3 2009J. Nilsson Abstract. Current strategies for prevention of cardiovascular disease focus on risk factor intervention. Although these have been proven both safe and effective results from randomized clinical trials suggest that it is difficult to achieve relative risk reductions exceeding 40% with this approach. To further improve efficacy future therapies must aim at targeting the actual disease process in the arterial wall. Emerging evidence have identified an important role of the immune system in atherosclerosis and suggest that modulation of autoimmune responses against oxidized LDL and other antigens in the atherosclerotic plaque represent one possible new approach to disease prevention. Oxidized LDL is targeted by both antibody-mediated and cellular immune responses and as much as 10% of the T cells in atherosclerotic plaques are oxidized LDL-specific. Immune activation in the atherosclerotic plaque is primarily of the pro-inflammatory Th1-type and inhibition Th1 immunity reduces atherosclerosis in experimental animals. Atherosclerosis vaccines based on antigens derived from LDL have been developed to modulate these processes. Their mechanisms of action remain to be full characterized but may involve expression of protective antibodies that facilitate the removal of oxidized LDL and antigen-specific regulatory T cells that counteract Th1 autoimmunity against oxidized LDL. In this review we will discuss the possibilities and challenges encountering the translation of immune-modulatory therapy for atherosclerosis from the experimental stage into the clinic. [source] Hepatitis C virus-specific T-cell immune responses in seronegative injection drug usersJOURNAL OF VIRAL HEPATITIS, Issue 1 2009M. Zeremski Summary., T-cell responses to hepatits C virus (HCV) antigens have been reported in high-risk HCV seronegative persons, suggesting that an effective cellular immune response might be able to clear infection without the development of antibodies. Such findings, however, could be explained by waning antibody or cross-reactivity to other antigens. To address these issues, we evaluated HCV-specific T-cell responses in 26 young (age 18,33 years) aviremic, seronegative injection drug users (IDUs) (median duration of injection, 6 years) by interferon-, enzyme-linked immunospot (ELISpot) assay using 429 overlapping HCV peptides pooled in 21 mixes. Seventeen aviremic, seropositive IDUs (spontaneous resolvers) and 15 healthy people were used as positive and negative controls, respectively. The percentage of patients with HCV-specific cellular immune responses was similar in seronegative and seropositive aviremic IDUs (46%vs 59%, P = 0.4), while these responses were not detected in any of the negative controls. Among the seronegative IDUs, six (23%) had intermediate to very strong responses to 10,20 peptide mixes and another six (23%) had moderately strong responses for two to six mixes. The 12 seronegative IDUs with HCV-specific T-cell responses had higher demographical and behavioural risk profiles than the 14 IDUs without T-cell responses (estimated risk of HCV infection, 0.47 vs 0.26, P < 0.01). In conclusion, HCV-specific T-cell responses are common among high-risk, seronegative IDUs. The responses are broad and are associated with risk factors for HCV exposure, suggesting that they reflect true exposure to HCV in seronegative persons. [source] Diagnosis of pulmonary tuberculosis using MTB12 and 38-kDa antigensRESPIROLOGY, Issue 3 2008Ji-Sook LEE Background and objective: Mycobacterium tuberculosis MTB12 protein plays an essential role in pro-inflammatory responses during the early stages of human pulmonary tuberculosis (TB), even though the T-cell immunoreactivity of MTB12 is weaker than that of the 30-kDa antigen (Ag). The objective of this study was to evaluate the humoral immune responses induced by MTB12 Ag during human TB. Methods: Using an ELISA, anti-MTB12 IgG levels in the sera of TB patients and healthy controls were compared with those induced by the 30-kDa Ag and 38-kDa Ag, or both. Results: In TB patients, the sensitivity and specificity of MTB12 Ag were similar to those of other antigens at 53.0% and 95.4%, respectively. However, the sensitivity increased to 73.0% when the combination of MTB12 and 38-kDa Ag was measured. Specificity remained high when a combination of the individual antigens was used. ELISA results showed that after anti-tuberculosis treatment, the mean IgG levels against MTB12 alone or MTB12 plus 38-kDa Ag were significantly increased in the TB patients, while those against MTB12 plus 30-kDa Ag were not (P < 0.05). Conclusions: Collectively, these data suggest that MTB12, in combination with 38-kDa Ag, can be used to increase the accuracy of pulmonary TB diagnosis. [source] A study of the antigenicity of Rickettsia helvetica proteins using two-dimensional gel electrophoresisAPMIS, Issue 4 2009NEDAA HAJEM Rickettsia helvetica is an obligate intracellular Gram-negative microorganism found in Ixodes ricinus ticks. When R. helvetica was first discovered in 1979, little was known about its physiology and it fell into oblivion until it recently was suspected of being pathogenic to humans. However, all efforts to isolate R. helvetica from patients have been unsuccessful, although serological responses against R. helvetica can be demonstrated. The aim of our study was to investigate the protein profile of R. helvetica and study the antigenicity of its proteins using two-dimensional (2D) immunoblot in order to characterize the immunological response against R. helvetica infection. Our results show that in addition to the known PS120 and OmpB antigenic R. helvetica proteins, three other antigens exist: a 60 kDa GroEL protein, a 10 kDa GroES protein and a hitherto unknown 35 kDa hypothetical protein that has similarities with ORF-RC0799 of Rickettsia conorii. Furthermore, the lipopolysaccharide showed strong antigenicity. In this study, we present the first proteome map and the first 2D immunoblot profile of R. helvetica and finally we present the 35 kDa R. helvetica as an additional antigen to the previously known rickettsial antigens. [source] Increased aeroallergen-specific interleukin-4-producing T cells in asthmatic adultsCLINICAL & EXPERIMENTAL ALLERGY, Issue 12 2002P. Pala Summary Background Asthma, atopy and some forms of respiratory syncytial virus (RSV) disease are thought to be caused by T cells making IL-4 (Th2 cells). However, not all patients with similar patterns of clinical disease have the same underlying pathogenesis and the ability to detect immunopathogenic T cells by examination of the peripheral blood remains in doubt. With the prospect of specific immunotherapy for diseases caused by T cell subsets, it is important to determine whether peripheral blood mononuclear cell (PBMC) reactivity can be used to establish the presence of immunopathogenic responses and therefore to predict therapeutic effects. Objective To detect IL-4 and IFN-, production as markers of Th1 and Th2 responses in the peripheral blood of atopic and asthmatic adults. Methods PBMC from 22 adult asthmatics (18 of whom were atopic) and 21 non-asthmatic volunteers (ten of whom were atopic) were stimulated with cat, birch and house dust mite allergens, human rhinovirus, RSV and recombinant chimaeric F/G protein from RSV in vitro. ELISPOT assays were used to enumerate cells producing IL-4 and IFN-,. Results Asthmatics had a sixfold increase in frequencies of IL-4-producing cells to cat and birch allergen (median values: 37 vs. 7 per million PBMC, P < 0.01 and 20 vs. 3 per million PBMC, P < 0.04, respectively) compared to non-asthmatics. By contrast, non-asthmatic atopics showed no specific increase in antigen-specific IL-4 responses and there was no evident correlation between skin prick test reactivity and ELISPOT results. Atopics had significantly more IFN- ,-producing cells specific for FG than nonatopics. while IFN-, and IL-4 responses to other antigens were not significantly different. Conclusion Enhanced IL-4 responses to non-viral aeroallergens are seen in adults with asthma, while enhanced IFN-, responses to viral antigen FG were seen in atopics. In practical terms, ELISPOT assays for specific cytokines may provide a method that could be used to monitor antigen-specific T cell responses in peripheral blood. [source] | ||||||||||