Search results for "HLA-B"
showing 10 items of 71 documents
Genome-based in silico identification of new Mycobacterium tuberculosis antigens activating polyfunctional CD8+ T cells in human tuberculosis.
2011
Although CD8(+) T cells help control Mycobacterium tuberculosis infection, their M. tuberculosis Ag repertoire, in vivo frequency, and functionality in human tuberculosis (TB) remains largely undefined. We have performed genome-based bioinformatics searches to identify new M. tuberculosis epitopes presented by major HLA class I supertypes A2, A3, and B7 (covering 80% of the human population). A total of 432 M. tuberculosis peptides predicted to bind to HLA-A*0201, HLA-A*0301, and HLA-B*0702 (representing the above supertypes) were synthesized and HLA-binding affinities determined. Peptide-specific CD8(+) T cell proliferation assays (CFSE dilution) in 41 M. tuberculosis-responsive donors ide…
Elevated levels of anti-endotoxin antibodies in patients with bilateral idiopathic acute anterior uveitis
2010
. Purpose: Endotoxins have been proved to be responsible for acute anterior uveitis (AAU) in animals in a well-established experimental model of endotoxin-induced uveitis (EIU). The purpose of our study was the detection of antibodies against endotoxins of selected enterobacteria in the serum of patients with idiopathic AAU and searching for correlations between the levels of these antibodies and the presence of HLA-B27 antigen as well as characteristic signs of EIU such as bilaterality and the absence of spontaneous recurrences of the disease. Methods: Reactions of serum IgG antibodies with lipopolysaccharides (LPSs) of Escherichia coli O1, E. coli O10, E. coli O111, E. coli J5, and Kleb…
Disease-associated polymorphisms in ERAP1 do not alter endoplasmic reticulum stress in patients with ankylosing spondylitis
2014
The mechanism by which human leukocyte antigen B27 (HLA-B27) contributes to ankylosing spondylitis (AS) remains unclear. Genetic studies demonstrate that association with and interaction between polymorphisms of endoplasmic reticulum aminopeptidase 1 (ERAP1) and HLA-B27 influence the risk of AS. It has been hypothesised that ERAP1-mediated HLA-B27 misfolding increases endoplasmic reticulum (ER) stress, driving an interleukin (IL) 23-dependent, pro-inflammatory immune response. We tested the hypothesis that AS-risk ERAP1 variants increase ER-stress and concomitant pro-inflammatory cytokine production in HLA-B27(+) but not HLA-B27(-) AS patients or controls. Forty-nine AS cases and 22 healthy…
klebsiella pneumoniae-reactive t cells in blood and synovial fluid of patients with ankylosing spondylitis comparison with hla–b27 + healthy control …
1995
Objective To study the frequency of Klebsiella pneumoniae-responsive T cells in the peripheral blood (PB) of ankylosing spondylitis (AS) patients compared with that in healthy HLA-B27+ donors, and to examine T lymphocyte clones (TLC) derived from AS patient synovial fluid (SF) for the presence of Klebsiella reactivity. Methods Limiting dilution analysis of PB T cells in 8 patients with active AS and in 8 HLA-B27+ healthy subjects was used to determine the frequency of PB T cells responsive to K pneumoniae and Escherichia coli GroEL. SF T cells from a patient with active AS were cloned, and 125 TLC were characterized in proliferation assays. Results There were fewer T cells in the PB of AS p…
Pathogenesis of autoimmune diseases associated with 8.1 ancestral haplotype: a genetically determined defect of C4 influences immunological parameter…
2003
Abstract Subjects with certain HLA alleles have a higher risk of specific autoimmune diseases than those without these alleles. The 8.1 ancestral haplotype (AH) is a common Caucasoid haplotype carried by most people who type for HLA-B8,DR3. It is unique in its association with a wide range of immunopathological diseases. To gain insight into the identification of the mechanism(s) of disease susceptibility of 8.1 AH carriers, we have investigated the prevalence of circulating immune complexes and non-organ-specific autoantibodies in healthy carriers of the haplotype. The results show that carriers of 8.1 AH display both a significant increased prevalence of immune complexes and higher titers…
Genetic control of immune response in carriers of the 8.1 ancestral haplotype: correlation with levels of IgG subclasses: its relevance in the pathog…
2007
Ancestral haplotype (AH) 8.1(HLA-A1, Cw7, B8, TNFAB*a2b3, TNFN*S, C2*C, Bf*s, C4A*Q0, C4B*1, DRB1*0301, DRB3*0101, DQA1*0501, DQB1*0201) seems to be associated with susceptibility to autoimmune diseases. Different mechanisms are probably involved in increasing autoimmunity, such as unbalanced cytokine production and the lack of C4A protein. So AH 8.1 modifies immune response in many ways. In this study we demonstrate that IgG2 serum levels were significantly lower in 8.1 AH carriers than in 8.1 AH non-carriers. On the contrary, as regards IgG1, IgG3, IgG4 serum levels, no significant differences were observed between the two groups. In AH 8.1 carriers low IgG2 levels might take to slower cl…
Genetic control of immune response in carriers of ancestral haplotype 8.1: the study of chemotaxis.
2007
In all caucasian populations the association of an impressive number of autoimmune diseases with genes from the HLA-B8, DR3 hap- lotype that is part of the ancestral haplotype (AH) 8.1 HLA-A1, Cw7, B8, TNFAB∗a2b3, TNFN∗S, C2∗C, Bf∗s, C4A∗Q0, C4B∗1, DRB1∗0301, DRB3∗0101, DQA1∗0501, DQB1∗0201 has been reported by different research groups. This haplotype, which is more common in northern Europe, is also associated with a number of immune system dysfunctions in healthy subjects. Analyzing the data according to gender, some dysfunc- tions are observed in women but not in men, in agreement with the role of X-linked genes and/or estrogens in the development and progression of autoimmune diseases.…
Natural killer and lymphokine-activated killer activity in HLA-B8,DR3-positive subjects.
1993
Abstract The haplotype HLA-B8,DR3 is over-represented in several autoimmune diseases, implying that genes predisposing people to these disorders are linked to this haplotype. In these diseases, various dysfunctions reflecting an impairment of the immune system have been found. Several reports indicate also that in HLA-B8,DR3-positive healthy subjects similar disorders may be demonstrated. In the present work, we have evaluated NK and LAK activity in these subjects. The study has been performed on monocyte-depleted peripheral blood MNCs by using the K-562 cell line as a target for NK activity and the HL-60 cell line for as a target LAK activity. LAK cells were obtained by incubating MNCs for…
Markers of T Lymphocyte Activation in HLA-B8, DR3 Positive Individuals
1990
Many autoimmune diseases are associated in Caucasians with HLA-B8 and/or HLA-DR3 antigens. There is evidence that bearers of these antigens may display significant changes in immune parameters when compared to individuals not having these antigens. Recently, increased numbers of blood activated T lymphocytes have been reported in the majority of these diseases. The increase in activated blood T lymphocytes is paradoxically characterized by an in vitro impairment of T cell activation. Particularly, an inadequate production of interleukins has been observed. We have studied blood levels of activated T cells in HLA-typed, healthy subjects. The results show that the percentage of activated T ce…
HLA-B8,DR3 haplotype affects lymphocyte blood levels
1997
The number of lymphocytes in the blood is constant, pointing to an effective control of circulating lymphocyte values. The mechanisms of this regulation are uncertain, although it is likely that the number of blood lymphocytes is conditioned by hormones, homing factors and cytokines whose production is at least partly restrained by genetic factors. Particularly genetic factors linked to major histocompatibility complex (MHC) appear to be involved. In human beings a decreased number of blood lymphocytes has been described in healthy subjects carrying the Human Leucocyte Antigens (HLA) haplotype HLA-B8,DR3. In the present study, to inquire into the mechanisms of this lymphocyte decreased numb…