Search results for "MHC"
showing 10 items of 233 documents
HLA-DRB1*1301 AND *1302 protect against chronic hepatitis B
1997
Abstract Background/Aims: The outcome of acute hepatitis B infection may be influenced by host factors like the major histocompatibility complex (MHC). We have investigated MHC class I and class II antigens in patients with chronic hepatitis B compared to a healthy control population. To confirm the findings of this first study we performed a second study in a group of subjects who had spontaneously recovered from acute hepatitis B infection. Methods: Frequencies of MHC class I and class II antigens were analyzed in patients with chronic hepatitis B virus infection and in control subjects. MHC class I typing was done by standard microlymphocytotoxicity assays. DRB1 and DQA1 genotypes were d…
Immunoselection in vivo: independent loss of MHC class I and melanocyte differentiation antigen expression in metastatic melanoma
1997
Peptides derived from melanocyte differentiation antigens have been identified as targets for MHC class I-restricted cytolytic T lymphocytes (CTLs) in human melanoma Regression of antigen-expressing tumors as well as selection of antigen-loss variants in the presence of antigen-specific CTLs have previously been reported. In the present study, we determined the expression of the melanocyte differentiation antigens Melan A/MART-1 and tyrosinase by mRNA analysis and by immunohistochemical staining with the monoclonal antibodies (MAbs) A103 and T311. Co-expression of Melan A/MART-1 and tyrosinase was detected by both methods in 18/20 melanomas tested. However, immunohistochemistry provided add…
Microsatellite allele A5.1 of MHC class I chain-related gene A is associated with latent autoimmune diabetes in adults in Latvia.
2006
NIDDM is one of the most common forms of diabetes. The diagnosis is based on WHO classification, which is a clinical classification and misses the autoimmune diabetes in adults. Therefore, among the clinically diagnosed NIDDM cases, there can be a certain number of patients with latent autoimmune diabetes in adults (LADA). The MICA gene is located in the MHC class I region and is expressed by monocytes, keratinocytes, and endothelial cells. Sequence determination of the MICA gene identifies trinucleotide repeat (GCT) microsatellite polymorphism, which identifies 5 alleles with 4, 5, 6, and 9 repetitions of GCT (A4, A5, A6, and A9) or 5 repetitions of GCT with 1 additional G insertion for al…
An Intergenic rs9275596 Polymorphism on Chr. 6p21 Is Associated with Multiple Sclerosis in Latvians
2020
Background and objectives: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system, leading to demyelination of neurons and potentially debilitating physical and mental symptoms. The disease is more prevalent in women than in men. The major histocompatibility complex (MHC) region has been identified as a major genetic determinant for autoimmune diseases, and its role in some neurological disorders including MS was evaluated. An intergenic single-nucleotide polymorphism (SNP), rs9275596, located between the HLA-DQB1 and HLA-DQA2 genes, is in significant association with various autoimmune diseases according to genome-wide association studies (GWASs). A cumulat…
The HLA locus and multiple sclerosis in Sicily
2005
The authors report the analysis of HLA-class II allelic heterogeneity in a well characterized multiple sclerosis (MS) Sicilian dataset. Family-based association analysis revealed evidence for excess transmission to affected individuals for alleles HLA-DRB1*1501, DRB1*04, and DQB1*0302. When analyzed as haplotypes, the authors observed excess transmission for the DRB1*0400-DQB1*0302 haplotype. Sicilian patients share the HLA-DRB1*1501 susceptibility allele with affecteds living in continental Italy, but also display the allelic heterogeneity that characterizes Mediterranean populations.
Relationship Between Human Leucocyte Antigen Class I and Class II and Chronic Idiopathic Urticaria Associated With Aspirin and/or NSAIDs Hypersensiti…
2006
Background. HLA genes play a role in the predisposition of several diseases. The aim was to analyze the prevalence of HLA class I phenotypes and HLA-DRB1*genotype in patients with CIU associated with ASA and NSAIDs hypersensitivity (AICU).Methods. 69 patients with AICU, and 200 healthy subjects.Results. Subjects with HLA-B44 and HLA-Cw5 antigens were more represented in patients with AICU than in control group. Subjects with HLA-A11, HLA-B13, HLACw4, and HLA-Cw7 antigen were more represented in control group than in patients with AICU. Multiple logistic regression demonstrated an association of HLA-Cw4 and HLA-Cw7 with a lower risk of AICU, whereas carriers of HLA-B44 phenotype had a higher…
Association between the MHC class I gene HFE polymorphisms and longevity: a study in Sicilian population.
2001
Classes I and II human leukocyte antigens (HLA) genes encode highly polymorphic heterodimeric glycoproteins involved in the control of immune responses. The HLA class I gene HFE seemingly no longer participates in immunity because it has lost its ability to bind peptides and it has acquired the ability to form complex with the receptor for iron-binding transferrin by regulating iron uptake by intestinal cells. Thus, it indirectly regulates immune responses too, because iron availability plays a role in specific and non-specific immune responses. The distribution of HFE polymorphisms in Sicilian centenarians and nonagenarians was studied to evaluate if HFE alleles might be represented differ…
[Correlation, in previously treated HIV-1 positive patients, between hypersensitivity reaction to abacavir and the presence of the HLA-B*5701 allele].
2009
Abstract Introduction Hypersensitivity reaction to abacavir (a powerful inverse transcriptase inhibitor) is a serious adverse effect that limits its use in antiretroviral treatment and requires a high level of clinical surveillance. Certain haplotypes of the primary histocompatibility complex proteins (HLA-B*5701) are very significant predictors of the risk of hypersensitivity to this drug. The purpose of this study is to identify the cases where a probable hypersensitivity reaction to abacavir presented the HLA-B*5701 allele. Method A retrospective study was conducted in all HIV-1 positive adult patients infected treated with abacavir between January 2000 and December 2007, in Department 6…
Major histocompatibility complex and sporadic Alzheimer's disease: a critical reappraisal
2003
Epidemiological data suggest that some genetic determinants of Alzheimer's disease (AD) might reside in those polymorphisms for the immune system genes that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, MHC polymorphisms have been the focus of a large number of AD association studies. Class Ia, Ib (hemochromatosis gene (HFE)), class II and class III (complement, tumour necrosis factor and heat shock proteins) alleles have been studied. Nearly every positive result has been followed by several studies that have failed to replicate it or that have contradicted it. Several factors, including methodological biases, might explain these dis…
IgG1 anti-epidermal growth factor receptor antibodies induce CD8-dependent antitumor activity
2014
Anti-EGFR monoclonal antibodies (mAb) like Cetuximab are commonly used for treatment of EGFR+ solid tumors mainly by exerting their therapeutic effect through inhibition of signal transduction. Additionally, IgG1 is a potent mediator of antibody-dependent cytotoxicity (ADCC). In case of the IgG1, Cetuximab induction of ADCC in vivo is controversially discussed. In our study, we investigated the efficiency of Cetuximab-mediated ADCC in a humanized mouse tumor model in vivo and analyzed the contribution of immunologic processes toward antitumor activity. Therefore, we used immunodeficient NOD/Scid mice transgenic for human MHC class I molecule HLA-A2 and adoptively transferred human HLA-A2+ P…