Search results for "HLA-DQ alpha-Chains"
showing 7 items of 7 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…
Analysis of TCR Vbeta repertoire and cytokine gene expression in patients with idiopathic dilated cardiomyopathy
2001
Although the etiopathogenesis of idiopathic dilated cardiomyopathy (IDC) is still unclear, it is widely accepted that a complex interplay between viral infections and immune mechanisms is the basis of disease genesis. Previously, we showed that heart-infiltrating T cells of patients suffering from acute, fulminant Coxsackie virus B3+-IDC shared a preferential usage of three variable gene segments of the T cell receptor beta chain-(TCR-Vbeta) encoding families Vbeta3, 7 and 13.1. This indicated the possible presence of a superantigen-driven immune response. Here, we further investigated the IDC immunological scenario by analysing different phenotypes of heart-infiltrating cells: TCR repertoi…
Analysis of HLA-DQA, HLA-DQB frequencies in a group of Sardinian centenarians
2006
Human leukocyte antigen (HLA) alleles, regulating type and intensity of the immune response, might influence life expectancy. In previous case-control studies the authors have demonstrated that both HLA-DR and -DQ alleles are not associated with longevity in the Sardinian population. On the other hand, association studies are subjected (as part of the homogeneity of the population in terms of geographic origin) to a number of possible confounding factors. Therefore, the authors typed the HLA-DQA1 and HLA-DQB1 alleles in 24 sibs (age range 85 to 97) of 17 centenarians by PCR-SSP. Sib pair analysis showed non-significant differences between the observed and expected percentage of DQA* or DQB1…
MHC class II genes influence the susceptibility to chronic active hepatitis C
1997
Chronic hepatitis C develops in more than 70% of hepatitis C virus infected subjects. Viral factors influence the disease course, but little is known about the importance of host factors.Frequencies of major histocompatibility complex (MHC) class I and class II antigens were analyzed in two groups of patients with chronic hepatitis C virus infection and in control subjects. MHC class I typing was done by standard microlymphocytotoxicity assays. DRB1 and DQA1 genotyping was done by PCR based typing methods.DRB1*0301 was found in 26 of 75 patients with chronic hepatitis C virus infection (34.7%) and in 12 of 101 control subjects (11.9%) (relative risk 3.9; p0.001). Homozygosity for this allel…
Experience with the PCR-based HLA-DQ? DNA typing system in routine forensic casework
1993
The results of HLA-DQ alpha typing from 42 routine forensic cases using the polymerase chain reaction (PCR) were analyzed regarding the reliability, discrimination efficiency and informative value of this system in a given case. The cases included stain typing from a variety of different substates, i.e. blood and semen stains, mixed body fluids, single hairs, cigarette butts, material from fingernail scratches, as well as identification and paternity cases on postmortem and fixed tissue. A total of 125 individual stain and tissue samples were included. PCR amplification was achieved in 70% of these samples. In cases with mixed body fluids, e.g. sperm and vaginal cells from rape cases, DQ al…
Common variants in the HLA-DQ region confer susceptibility to idiopathic achalasia
2014
Idiopathic achalasia is characterized by a failure of the lower esophageal sphincter to relax due to a loss of neurons in the myenteric plexus(1,2). This ultimately leads to massive dilatation and an irreversibly impaired megaesophagus. We performed a genetic association study in 1,068 achalasia cases and 4,242 controls and fine-mapped a strong MHC association signal by imputing classical HLA haplotypes and amino acid polymorphisms. An eight-residue insertion at position 227-234 in the cytoplasmic tail of HLA-DQ beta 1 (encoded by HLA-DQB1*05:03 and HLA-DQB1*06:01) confers the strongest risk for achalasia (P = 1.73 x 10(-19)). In addition, two amino acid substitutions in the. extracellular …
Analysis of HLA-DRB1,DQA1,DQB1 haplotypes in Sardinian centenarians
2008
Some genetic determinants of longevity might reside in those polymorphisms for the immune system genes that regulate immune responses. Many longevity association studies focused their attention on HLA (the human MHC) polymorphisms, but discordant results have been obtained. Sardinians are a relatively isolate population and represent a suitable population for association studies. Some HLA-DR and DQ alleles form very stable haplotypes with a strong linkage disequilibrium. In a previous study on Sardinian centenarians we have suggested that HLA-DRB1 *15 allele might be marginally associated to longevity. HLA-DR,DQ haplotypes are in strong linkage disequilibrium and well conserved playing a ro…