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Immunogenetics of HLA class II in Israeli Ashkenazi Jewish, Israeli non-Ashkenazi Jewish, and in Israeli Arab IDDM patients.

The distribution of HLA class II alleles and genotypes in IDDM patients was examined in the three main Israeli ethnic groups: Ashkenazi Jews, non-Ashkenazi Jews, and Arabs. Molecular sequence specific oligonucleotide probe analysis was performed for DRB1, DQA1, and DQB1 genes. The DRB1*03011, DQA1*05 DQB1*02/DRB1*0402, DQA1*03, DQB1*0302 genotype was found to be the main susceptibility genotype in all three groups, with differences in the degree of association. In addition to DRB1*0402 (more frequent among Ashkenazi Jews), DRB1*0405, another subtype of DRB1*04, was found to be more prevalent among non-Ashkenazi Jews and Arabs. Many alleles were found to be negatively associated with insulin dependent diabetes mellitus (IDDM). This could be a result of the high frequency of susceptible alleles, or of linkage disequilibrium to a primary negatively associated allele. The strongest negative association was observed for DQB1*0301 in all three ethnic groups. The alleles DRB1*1401, DRB1*1501, DQB1*05031, DQB1*0602, and DQB1*0609 were not detected in any of the 202 IDDM patients, and are probably either strongly protective or in linkage with such alleles. Despite the differences found between the three ethnic groups, an overall analysis shows that the DRB1*04 alleles that account for susceptibility to IDDM in the Israeli population (DRB1*0402 and *0405) are the same as those responsible for susceptibility to IDDM in a number of other Mediterranean populations. In contrast, the susceptible allele in most Caucasian populations is DRB1*0401. It is noteworthy that the susceptible alleles DRB1*0402/05 for Mediterranean and DRB1*0401 for Caucasian populations are also frequent in the respective healthy populations. These findings support the results obtained in other studies, which point to a genetic relationship between the Israeli and Mediterranean populations.

Alleles↗

HLA class II immunogenetics of IDDM in Yemenite Jews.

The association between HLA-DR and DQ and insulin dependent diabetes mellitus (IDDM) was analyzed in 47 patients and 76 controls of Yemenite Jewish origin. The IDDM susceptibility alleles DRB1*03011, DQA1*0501, DQB1*02 and DRB1*0402, DQA1*0301, DQB1*0302 found in Caucasians had a very strong predisposing effect also in the Yemenite IDDM group. The DRB1*07, DQA1*0201 and DQB1*02 alleles were found to have a strong negative association with IDDM. None of the patients carried DRB1*07 and DQA1*0201 compared with healthy controls (43.7%). Our analysis revealed that the DRB1*03011 DQA1*0501 DQB1*02/DRB1*04 DQA1*03 DQB1*0302 heterozygous genotype confers the highest susceptibility (59.6% in patients vs. 0% in controls). The homozygous DRB1*03 and DRB1*04 genotypes were also found to be positively associated with the disease. 81% of the patients compared to 1.3% of controls carried the susceptibility alleles on both haplotypes. In conclusion, the development of IDDM in Yemenite Jews is strongly dependent on the presence of the susceptibility HLA alleles and on the absence of the DRB1*07 haplotype. The Yemenite Jewish group is uniquely homogenous with regard to genetic susceptibility factors involved in the process of IDDM, and may thus be an ideal model for further genetic studies.

Alleles↗

HLA class II immunogenetics and incidence of insulin-dependent diabetes mellitus in the population of Cantabria (Northern Spain).

HLA class II genes were analyzed to study IDDM susceptibility in Cantabria (Northern Spain). Patients showed highly significant increases in DRB1*0301 (RR = 4.581, p < 0.00005), DRB1*0401 (RR = 2.6, p < 0.05), DRB1*0402 (RR = 8.78, p < 0.05) and DRB1*0405 (RR = 14.73, p < 0.005). Highly significant diferences were in the DQA1*0301 (RR = 3.62, p < 0.000005) and DQA1*0501 (RR = 2.13, p < 0.05) alleles. DQB*0201 (RR = 4.1, p < 0.00005) and DQB1*0302 (RR = 5.42, p < 0.000005) alleles were also significantly increased. A significant increase in DRB1*0402-DQA1*0301-DQB1*0302 (RR = 16.18, p < 0.05), DRB1*0405-DQA1*0301-DQB1*0302 (RR = 16.12, p < 0.05), DRB1*0301-DQA1*0501-DQB1*0201 (RR = 4.58, p < 0.00005) and DRB1*0401-DQA1*0301-DQB1*0302 (RR = 4.36, p < 0.005) was apparent in the diabetic group, while the DRB1*1501-DQA1*0102-DQB1*0602 and DRB1*1401-DQA *0104-DQB1*05031 protective haplotypes (RR = 0.17 and 0.09, p < 0.0005 and 0.05, respectively) were significantly lower in patients. The absence of Asp57 and the presence of Arg52 were associated with disease in a dose-dependent manner. Several genotypes encoding the identical DQalpha52/DQbeta57 phenotype carried very different RRs. Finally, the Cantabrian population has the highest incidence of IDDM reported for Spain (15.2 of 100.000 in the 0-14 age group, Poisson's 95% CI: 10.6-19.3).

Adolescent↗

[Helicobacter pylori and immunogenetic factors of the host: relevance of the HLADQA1 *0102 and *0301 alleles in peptic ulcer].

AIM: To investigate the potential contribution of the *0102 and *0301 alleles of the HLADQA1 gene in Helicobacter pylori infection and peptic ulcer disease in a Spanish Caucasian population. PATIENTS AND METHODS: We studied 163 patients with peptic ulcer (117 duodenal ulcers and 46 gastric ulcers; 111 with recent upper gastrointestinal hemorrhage) and 90 controls. The *0102 and *0301 alleles of the HLADQA1 gene were typed by polymerase chain reaction using genomic DNA. H. pylori infection were determined by breath test and/or serology. The cytotoxins CagA and VacA were investigated using serology (Western-blot) in 98 patients and 48 controls with H. pylori infection. RESULTS: H. pylori infection was found in 94.6% of patients with duodenal ulcer, in 84.4% of those with gastric ulcer and in 67.4% of controls (p < 0.001). The distribution of the *0102 allele of the HLADQA1 gene was similar in patients (31.9%) and in controls (36.7%). The *0301 was more frequent in patients with gastric ulcer (32.6%) than in those with duodenal ulcer (16.2%) (p < 0.05) but no differences were found on comparison with the control group (24.4%). No differences were found when the groups were analyzed according to H. pylori infection, CagA- and VacA-positive strains, consumption of non-steroidal antiinflammatory drugs or previous history of ulcer or hemorrhage. CONCLUSION: The *0102 and *0301 alleles of the HLADQA1 gene did not alter susceptibility to H. pylori infection or the evolution of peptic ulcer disease in a Caucasian population in Spain.

Alleles↗

[Immunogenetics of systemic lupus: adequacy between HLA molecules class II and the germinal genes of antigen receptor of T-lymphocytes favours the production of various antibodies].

The study of 30 patients with systemic lupus and of 153 relatives failed to show any differences in HLA and TCR beta haplotype frequencies between patients and relatives. A significant interaction between TCR V beta and HLA-DR/DQ genes in the response to the peptide U1-RNP A 35-58 was demonstrated.

Antibody Formation↗

[Insulin-dependent diabetes and organ specific autoimmune diseases: a retrospective clinical and immunogenetic study of 165 consecutive cases].

We analysed clinical and immunological indexes in 165 caucasian adult patients presenting insulin-dependent diabetes mellitus associated with other organ-specific autoimmune diseases (type Ib IDDM). As diagnostic strategy, we recommend testing thyrogastric autoantibodies at diabetes onset and islet-cells antibodies three years after.

Adolescent↗

[Immunogenetic bases of systemic lupus erythematosus in humans].

INTRODUCTION: Systemic lupus erythematosus (SLE) is an autoimmune disease of unknown pathogenesis. Familial studies and concordance rates among affected twins suggest that human SLE has a strong genetic basis. CURRENT KNOWLEDGE AND KEY POINTS: Recent studies have emphasized that SLE, like other autoimmune diseases, is a complex genetic trait with contributions of both major histocompatibility complex (MHC) associated genes and multiple non-MHC genes. Recent significant advances have been made in the genetic analysis of complex traits, which allow the identification of new candidate genes in SLE. Among the genes reviewed in this article, some polymorphisms of Fc gamma receptor genes and other genes or loci localized on the long arm of the human chromosome 1 appear to be very promising. FUTURE PROSPECTS AND PROJECTS: The identification of new susceptibility genes in SLE will certainly provide important insights into the breakdown of self-tolerance mechanisms leading to autoimmune diseases. To achieve this objective, the recruitment of a large number of genetic traits of multiplex families presenting with SLE is therefore essential. More than 125 multiplex families have been collected to date in France.

Animals↗

Familial clustering and immunogenetic aspects of IgA nephropathy.

IgA nephropathy (IgAN) has been assumed to develop sporadically in individuals. We review the recent clinical and laboratory evidence that supports a genetic influence in the immunopathogenesis in some patients. These data include (1) families with multiple members with the disease not sharing a known nephrotoxic factor, (2) clustering of the birthplaces of ancestors of large pedigrees with multiple affected members, suggesting a "founder effect," (3) DNA alleles and protein phenotypes associated with IgAN (or a clinical subset) in some patient populations or that cosegregate with the disease in families with multiple affected members, and (4) immunologic abnormalities of patients shared by relatives with renal disease. However, the lack of understanding the fundamental pathogenetic mechanisms hinders progress in the pursuit of genetically controlled process in this disease. Furthermore, the diagnosis requires a renal biopsy, and no therapy has been proven effective. Therefore, asymptomatic family members with IgAN may forego the invasive diagnostic procedure necessary to establish the diagnosis, and instances of familial disease may not be investigated. Nonetheless, the increasing awareness of families with multiple affected members offers an opportunity to investigate the hypothesized genetic influence in the pathogenesis of IgAN.

Genetic Markers↗

Immunogenetic markers and immune response in patients with recurrent oral ulceration.

20 patients, aged 20 to 72 years (mean 36.5 years), 14 with recurrent (RAS) and 6 with recurrent cicatrizing (RCAS) aphthous stomatitis were studied. 3 patients (15%) had the HLA locus A11 antigen, whose frequency in the Finnish population is 8%. 5 patients (25%) had B12, which occurs in 15% of the normal population. Results of routine serological tests were normal. All had normal serum levels of IgG, IgM, IgA and complements C3 and C4. 4 patients, 2 with RAS and 2 with RCAS, had raised serum IgE. Precipitating antibodies against milk protein were detected in 2 patients and against gluten in 1. In 4 patients, tests for immediate allergy were positive. 5 patients had antibodies to double-stranded DNA. Delayed hypersensitivity reactions were normal, and the PHA stimulation of lymphocytes elicited normal T-cell responses in all patients except one with RCAS. In this patient, there was a striking parallelism between an increase in PHA-reactive lymphocytes and clinical improvement. The serum of this patient contained a binder for 125I-labelled PHA, a binder not consistently detected in the other patients with ROU. Lymphocyte dysfunction may play a rôle in ROU. Of the 16 biopsy specimens of aphthous tissue studied by direct immunofluorescence for IgG, IgM, IgA, fibrinogen and C3, 15 specimens contained deposits of C3 in and along mucosal vessels, whereas among the 15 controls only 1 specimen of erosive lichen planus showed deposits of C3 along capillary walls. Immune complexes precipitating in capillary walls appear to be a common feature of ROU.

Adult↗

[The Atri system. Immunogenetic lymphocytic system associated with ABO and ABH secretory systems].

The antigen Atri can be detected on the lymphocytes of 5.19% of ABH Secretor A individuals. The Atri substance is present in the plasma of the same individuals and can be fixed on group O erythrocytes. It is also found in the saliva of 30/32 A individuals not secreting substance A. Its existence in the saliva of A Secretor individuals, however, cannot be proved due to the presence of both the A and Atri antigens. The Atri substance is neutralized by the soluble substance A extracted from the gastric mucous of a pig. Yet the A and Atri antigens can be shown to be distinct on lymphocytes by redistribution of the corresponding sites and blocking of the A sites by an immune anti-A. On a genetic level, the Atri specificity might belong to a lymphocyte system comprising three alleles: Atri, RB and W100. These three specificities have the common characteristic of being expressed on a certain percentage of the lymphocytes of group A individuals. This system, provisionally named Atri, is functionally associated with the ABO system and secretor system. Nevertheless, the fact that in several families the Atri antigen is not expressed by the parents shows that its expression on lymphocytes requires the intervention of at least one gene in addition to the A and Se genes.

ABO Blood-Group System↗

The roles of adoptive and active forms of immunotherapy in the cure of children suffering from acute lymphoid leukemia: a) underestimation of active immunotherapy benefit, b) its immunogenetic indications to select sensitive patients, hence prevent chemotherapy's late effects.

Children's acute lymphoid leukemia (ALL) chemotherapy started in 1948 with antimetabolites combined with steroids. It was enriched in 1959 with vincristine and cyclophosphamide and, in 1970, with daunomycin. It induced more and more apparently what were called complete remissions, and prolonged more and more the survivals without reducing however, until 1973, the (100%) mortality. It started to reduce it at the fifth year, to 20 and even 40% between 1973 and 1976, due to progressive and maximal intensification and duration of chemotherapy. It is in the same period that we proposed to apply in ALL remissions after relapses and in the first remissions of the most malignant type, allogeneic bone marrow grafts; we published the first success in human ALL in 1963, and clinically observed the same actions as those described experimentally: cytoablation of both leukemia and hematopoiesis, the latter being restored by the graft, whose reaction versus the residual neoplastic cells (called graft versus leukemia or GvL) appeared to be able to often eradicate them, at the cost however of a graft-versus-host reaction (both reactions sharing the same mechanism). One of us became a member of the Committee of the International Bone Marrow Transplant Registry, whose results showed the improvement in the prognosis of the aggressive form of ALL. The intensity and length established for chemotherapy for the most severe form of children's ALL have often been applied to the intermediary and to the least aggressive ones. The global 5-year survival increased to 60% between 1976 and 1984, and is around 80% today. But the registration of late debilitating or malignant effects of chemotherapy toxicities makes us wonder if some patients have not received an excessively intense and long application of cytostatics (often combined with ionizing radiations on CNS). In fact, the patients belonging to some HLA phenotypes (A33 and B17) have appeared to be especially often cured with active immunotherapy (killed leukemic cells and/or BCG), whose action was shown by specific cytotoxicity amplification, which was applied after short adjuvant chemotherapy, and hence is able to reduce the long chemotherapy incidence of debilitating or malignant late effects. Sakurai's group confirmed our absence of late relapses after ALL active immunotherapy, which contrasts with their risk after maintenance chemotherapy, whose minimal residual disease is a worrisome stumbling block to the cure.

Antineoplastic Agents↗

The immunogenetics of bone marrow transplantation.

It is now clear that it is not necessary to use an HLA genotypically identical donor to have a successful marrow transplant. However, it is equally clear that the likelihood of complications increases with each increment in histoincompatibility. The implication is that histocompatibility testing must be of the highest possible precision to choose the optimal donor, and to predict the risk of adverse alloreactivity. Most clinicians would seriously consider transplantation from a one locus-mismatched relative or an HLA-matched unrelated donor in virtually any situation in which transplantation from a matched sibling would be felt to be the standard of care. More thought would need to go into transplantation from a two or three locus-mismatched relative or a mismatched unrelated donor.

Bone Marrow Transplantation↗