Search results for "HLA"
showing 10 items of 664 documents
Bile duct epithelia as target cells in primary biliary cirrhosis and primary sclerosing cholangitis.
1997
Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are chronic autoimmune-mediated diseases of the biliary tree, resulting in a loss of bile ducts. There are morphological features that clearly distinguish them from each other: in PBC, there is overt destruction of the bile ducts with disruption of the basement membrane; in PSC there is abundant periductular fibrosis with shrinkage and subsequent loss of the bile ducts. In order to see if the disparate histopathology is paralleled by different immunohistology we looked at a panel of epitopes on bile duct epithelia especially to see if biliary epithelial cells may present as targets for cell mediated immune response. In…
Clinicopathological and Immunohistochemical Study of Oral Amalgam Pigmentation
2012
Amalgam tattoo, the most common exogenous oral pigmentation, can sometimes be confused with melanotic lesions, being then biopsied. We present the clinicopathological characteristics of 6 biopsied cases (5 females and 1 male) of oral amalgam pigmentation. The most common location was the gingival mucosa, followed by the buccal and palatal mucosa. Morphology and distribution (stromal, perivascular, perineural, endomysial) of pigmentation was variable; there was only 1 case with fibrous capsular reaction and likewise only a single case of granulomatous foreign body reaction. Morphological variability is conditioned by the timing and amount of the pigment deposit, which is often associated wit…
Autoimmune hepatitis in the elderly.
2001
Abstract OBJECTIVES: Autoimmune hepatitis (AIH) is widely believed to be a disease of young women and menopause. Little is known about the frequency and clinical characteristics in patients aged ≥65 yr. METHODS: We reviewed charts of 120 consecutive outpatients with known AIH to identify patients who were diagnosed at the age of 65 or older. These 20 patients (median age, 69 yr) were compared to the same number of younger patients (median age, 24 yr) with well-documented AIH from the same cohort. RESULTS: Seventeen percent (20/120) of our patients were ≥65 yr at the time of diagnosis. In the older patients median time to diagnosis was significantly longer than in the younger patients (8.5 >…
The Human Leukocyte Antigen-DPB1 Degree of Compatibility Is Determined by Its Expression Level and Mismatch Permissiveness: A German Multicenter Anal…
2021
T-cell epitope matching according to the TCE3 algorithm classifies HLA-DPB1 mismatches in permissive and non-permissive. This classification has been shown to be predictive for mortality and acute GvHD (aGvHD) events in large international cohorts. We retrospectively genotyped HLA-DPB1 in 3523 patients transplanted in Germany between 2000 and 2014 and in their unrelated donors using an Illumina amplicon-NGS based assay. Aim of the study was to evaluate DP-compatibility beyond the established TCE3 algorithm by assessing the combined effect of several DP-mismatch parameters on post-transplant outcome. We implemented an extended DP-mismatch assessment model where TCE3, DP allotype expression w…
Phenotypical and functional analysis of memory and effector human CD8 T cells specific for mycobacterial antigens
2006
Abstract Mycobacterium tuberculosis infects one-third of the global population and claims two million lives every year. Because memory CD8 T cells exhibit a high heterogeneity in terms of phenotype and functional characteristic, we investigated the frequency, phenotype, and functional properties of Ag85A epitope-specific HLA-A*0201 CD8 T cells in children affected by tuberculosis (TB) before and 4 mo after chemotherapy and healthy contact children. Using Ag85A peptide/HLA-A*0201 pentamer, we found a low frequency of blood peptide-specific CD8 T cells in tuberculous children before therapy, which consistently increased after therapy to levels detected in healthy contacts. Ex vivo analysis of…
RAPID AND EFFICIENT ANTIGEN PROCESSING AND PRESENTATION OF A PROTECTIVE AND IMMUNODOMINANT HLA-B*27-RESTRICTED HEPATITIS C VIRUS-SPECIFIC CD8+T CELL …
2012
HLA-B*27 exerts protective effects in hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections. While the immunological and virological features of HLA-B*27-mediated protection are not fully understood, there is growing evidence that the presentation of specific immunodominant HLA-B*27-restricted CD8+ T-cell epitopes contributes to this phenomenon in both infections. Indeed, protection can be linked to single immunodominant CD8+ T-cell epitopes and functional constraints on escape mutations within these epitopes. To better define the immunological mechanisms underlying HLA-B*27-mediated protection in HCV infection, we analyzed the functional avidity, functional profile, ant…
Antigens of the major histocompatibility complex in patients with chronic discoid lupus erythematosus.
1990
summary The frequencies of the major histocompatability complex class I, class II and class III antigens were determined in 130 patients (88 women and 42 men) with chronic discoid lupus erythematosus, and compared with those of 764 healthy controls. A significant increase in HLA-B7 (38.0% in the patients vs. 25·8% in the control group), HLA-B8 (29·5% vs. 17·4%), HLA-Cw7 (58·9% vs. 26·1%), HLA-DR2 (46·9% vs. 29·7%), HLA-DR3 (32·0% vs. 19·4%), HLA-DQwi (76·6% vs. 60·5%), and a decrease in HLA-A2 (41·9% vs. 55·7%) was found. The calculated relative risk values for the respective antigens markedly increased when two or more antigens were present in one patient, with a maximum relative risk valu…
Polymorphism of immunoglobulin enhancer element HS1,2A: allele *2 associates with systemic sclerosis. Comparison with HLA‐DR and DQ allele frequency
2007
OBJECTIVE: To investigate the relationship of the polymorphic enhancer HS1,2 central to the 3' enhancer complex regulatory region (IgH3'EC) of the immunoglobulin heavy chain genes with systemic sclerosis (SSc) disease and compare it with HLA-DR and DQ associations. METHODS: A total of 116 patients with SSc were classified as diffuse (dSSc) or limited (lSSc), and as carriers of antitopoisomerase I (anti-Scl70) or anticentromere (ACA) antibodies. Allele and genotype frequencies were assessed in the population as a whole and in the two major subsets, dSSc and lSSc. The concentration of peripheral blood immunoglobulin levels was also determined and analysed according to the genotypes. RESULTS: …
Immunoproteasome LMP2 60HH Variant Alters MBP Epitope Generation and Reduces the Risk to Develop Multiple Sclerosis in Italian Female Population
2010
BackgroundAlbeit several studies pointed out the pivotal role that CD4+T cells have in Multiple Sclerosis, the CD8+ T cells involvement in the pathology is still in its early phases of investigation. Proteasome degradation is the key step in the production of MHC class I-restricted epitopes and therefore its activity could be an important element in the activation and regulation of autoreactive CD8+ T cells in Multiple Sclerosis.Methodology/principal findingsImmunoproteasomes and PA28-alphabeta regulator are present in MS affected brain area and accumulated in plaques. They are expressed in cell types supposed to be involved in MS development such as neurons, endothelial cells, oligodendroc…
Human CD8 T lymphocytes recognize Mycobacterium tuberculosis antigens presented by HLA-E during active tuberculosis and express type 2 cytokines
2015
CD8 T cells contribute to protective immunity against Mycobacterium tuberculosis. In humans, M. tuberculosis reactive CD8 T cells typically recognize peptides associated to classical MHC class Ia molecules, but little information is available on CD8 T cells recognizing M. tuberculosis Ags presented by nonclassical MHC class Ib molecules. We show here that CD8 T cells from tuberculosis (TB) patients recognize HLA-E-binding M. tuberculosis peptides in a CD3/TCR αβ mediated and CD8-dependent manner, and represent an additional type of effector cells playing a role in immune response to M. tuberculosis during active infection. HLA-E-restricted recognition of M. tuberculosis peptides is detectab…