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HLA-DR and -DQ Serotyping
Published in M. Kam, Jeffrey L. Bidwell, Handbook of HLA TYPING TECHNIQUES, 2020
The HLA-DR specificities were first given official recognition following the 7th International Histocompatibility Workshop (IHW) in 1977, at which the reaction patterns of B cell-specific sera were correlated with the previously defined HLA-Dw typings of the cells reacting with them.1 The HLA-DQ antigens were first recognized as representing products of a locus separate from HLA-DR following the 9th IHW in 1984.2The number of HLA-DR and -DQ specificities given official recognition has increased in each succeeding IHW. Class II HLA-DP molecules are also expressed by B lymphocytes, but it is not yet possible to define the antigens of this series by serological typing methods.
Host Defense II: Acquired Immunity
Published in Constantin A. Bona, Francisco A. Bonilla, Textbook of Immunology, 2019
Constantin A. Bona, Francisco A. Bonilla
Both CD4+ and CD8+ T cells are important in sporozoite immunity, but again, there is no consistent correlation with protection from infection and the presence of one of these populations of sporozoite-specific T cells. T cell responses appear to diminish with ongoing infection, suggesting the development of specific and non-specific suppression. The latter is demonstrated by the diminished response to routine childhood immunization in infected children. HLA-DQ may play an important role in the generation of suppression since anti-DQ antibodies can prevent it.
The gastrointestinal tract
Published in Angus Clarke, Alex Murray, Julian Sampson, Harper's Practical Genetic Counselling, 2019
Coeliac disease is strongly associated with two specific HLA-DQ haplotypes, which will of course be transmitted in families. Other predisposing genetic factors vary between populations and an appropriate environmental trigger is necessary for disease. Human leucocyte antigen (HLA) testing is of little help in risk prediction for individual relatives.
HLA and amyotrophic lateral sclerosis: a systematic review and meta-analysis
Published in Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration, 2023
R. J. Nona, J. M. Greer, R. D. Henderson, P. A. McCombe
Another limitation is that HLA serological testing was the only method available at the time when these studies were done. This technique has been superseded by more specific DNA-based sequencing methods, which reveal multiple alleles within each of the broad serotypes (33–35). In particular, there was almost no testing of the HLA class II region, with only one of the studies testing for HLA-DR serotypes. More recently, on the basis of proposed potential links between celiac disease and ALS, one study from the Netherlands has tested whether carriage of selected HLA-DQ alleles (HLA-DQA1*05:01, DQB1*02:01, DQB1*02:02 and DQB1*03:02) that are associated with development of celiac disease correlate with development of ALS. For these specific alleles, no differences were found (36). Another study using a Han Chinese population of ALS patients tested for association with several single nucleotide polymorphisms (SNPs) that have been associated with a risk of development of frontotemporal dementia. Two of the SNPs map to between the HLA-DR alpha chain locus and the HLA-DRB5 locus, with one of them (rs9268856) being located within the DRB9 pseudogene locus. At rs9268856, there was significantly increased carriage of the AA genotype in ALS patients compared to controls; however, the frequency of this AA genotype was only 4.1% in controls and 8.2% in ALS patients (37). Although these were both large studies, the very narrow range of HLA alleles and SNPs that were investigated limits any conclusions regarding the role of HLA in ALS.
Diabetes mellitus as a vaccine-effect modifier: a review
Published in Expert Review of Vaccines, 2020
Thomas Verstraeten, Mark A. Fletcher, Jose A. Suaya, Sally Jackson, Cassandra K. Hall-Murray, Daniel A. Scott, Beate Schmöle-Thoma, Raul E. Isturiz, Bradford D. Gessner
Studying the impact of DM on vaccination is complicated by variations in the human immune response. Family and population analyses have found that both high responders and low or nonresponders to natural antigens exist. As a specific example, hepatitis B vaccines do not induce an adequate immune response in 5–10% of healthy adults based on genetic variations in immune response rather than a defined immune deficiency [21]. Some genetically based immunologic mechanisms have been defined, such as an association between HLA-DQ alleles and low responsiveness for a range of antigens mediated by CD8+ suppressor T cells [22]. Similarly, the HLA-DRB1*0701 allele was overrepresented among persons who failed to mount a neutralizing antibody response after influenza virus vaccination [23]. These findings complicate studying the role of DM as a vaccine-effect modifier. Nevertheless, the ad hoc study findings from CAPiTA [17] prompted us to review previous literature on the potential role of DM as effect modifier of vaccines’ responses.
Risk variation in celiac disease in a population from Southern Spain: evaluating the influence of the DQB1*02:02 allele frequency
Published in Scandinavian Journal of Gastroenterology, 2018
Carmen M. Cabrera, Isabel M. Méndez-López, Abelardo Caballero
Knowledge of the HLA-DQ risk genotypes in a population of patients with CD is important for establishing a risk gradient, since the DQB1 allele frequencies can range among populations. Hence, whereas the DQB1*02:01 allele has very similar frequencies in different populations around Europe, with the exception of people from Sardinia and North Africa (Figure 3), DQB1*02:02 is more prevalent in populations from Mediterranean countries, such as Spain and North Africa (Figure 4). This information is demanded by clinicians in laboratory test reports as part of routine practice. Indeed, one of the main objectives proposed in our study is the determination of a risk gradient based on the HLA-DR-DQ risk genotypes found in our celiac patients (Province of Málaga), and to provide this information to clinicians.