Sj?gren's syndrome (SS) is a chronic autoimmune disease characterized by dryness of the eyes and mouth. Currently, the highly polymorphic major histocompatibility complex (MHC) genes are the best documented genetic risk factor for the development of autoimmune disease. We examined the MHC class II alleles DRB1, DRB3, DRB4, DRB5, DQA1 and DQB1 in a group of Norwegian pSS patients and compared with a group of healthy controls. Because a number of studies have shown that some of the MHC class II alleles are not associated with the disease as a whole, but rather to the development of autoantibodies, anti-Ro52 autoantibodies in serum were measured and compared to MHC class II allele status. A clear association with pSS was detected for the DRB1*0301 and DRB3*0101 alleles, but these alleles were more closely associated with the presence of anti-Ro52 autoantibodies than with pSS itself. Moreover, the DQA1*0501 and DQB1*0201 alleles were only associated with the presence of anti-Ro52 autoantibodies. This study shows that the production of anti-Ro52 autoantibodies in pSS is associated with the DRB1*0301, DRB3*0101, DQA1*0501 and DQB1*0201 alleles which are in strong linkage disequilibrium.
HLA-DRB1, -DRB3, -DQA1 and -DQB1 alleles were determined by DNA typing in 51 Scandinavian patients with systemic lupus erythematosus (SLE) and 129 controls. DRB1*03,DRB3*0101,DQA1*0501,DQB1*0201 were significantly increased in the patient group, with relative risks (RR) of 2.80, 3.07, 3.55 and 2.12, respectively. These alleles are in strong linkage disequilibrium, and their possible relative contributions in predisposition to SLE are difficult to distinguish. The strongest association was found for DQA1*0501, which is in linkage disequilibrium with DRB1*03 as well as DRB1*11,12 (DR5). An increased frequency of DRB1*11,12 was observed (RR = 1.89, ns). No association with DRB1*15,16 (DR2) was found. The patients had a higher frequency of HLA class II homozygosity than the controls (RR = 5.05, p = 0.0005). When compared to the low-risk group (nonDRB1*03 class II heterozygotes), the cases homozygous for DRB1*03,DQA1*0501,DQB1*0201, known to be in linkage disequilibrium with the complement allele C4A*Q0, had the highest relative risk of developing SLE (RR = 16.39, p = 0.0002). However non[DRB1*03,DQA1*0501,DQB1*0201] class II homozygotes had a higher relative risk (RR = 4.68, p = 0.0147) than DRB1*03,DQA1*0501,DQB1*0201 heterozygotes, known to carry the C4A*Q0 allele (RR = 2.72, p = 0.0088). This may suggest that HLA class II molecules are directly involved in susceptibility to SLE.
Autoantibody production is commonly associated with particular HLA class II phenotypes. The aim of the present study was to investigate whether the presence of antiphospholipid (APL) antibodies and other autoantibodies in women with unexplained recurrent miscarriage was associated with particular human leukocyte antigen (HLA)-DR or -DQ alleles or linked epitopes which have previously been reported as being associated with the recurrent miscarriage syndrome or the presence of APL. In a total of 123 Danish and Czech women with recurrent miscarriage, serum was investigated for six different APL antibodies including anticardiolipin (ACL) antibody. Antinuclear antibodies (ANA), anti-zona pellucida antibodies and anti-sperm antibodies were also investigated. The women were HLA-DR and -DQ typed by DNA-based methods. The frequency of HLA-DR phenotypes did not differ significantly between APL antibody positive recurrent miscarriage patients and APL antibody negative recurrent miscarriage patients or healthy controls. Among ACL antibody positive recurrent miscarriage patients, significantly more were positive for the HLA-DR3 phenotype and negative for the HLA-DR2 phenotypes compared with healthy controls (P
The swine major histocompatibility complex (MHC) genomic region (SLA) is extremely polymorphic comprising high numbers of different alleles, many encoding a distinct MHC class I molecule, which binds and presents endogenous peptides to circulating T cells of the immune system. Upon recognition of such peptide-MHC complexes (pMHC) naïve T cells can become activated and respond to a given pathogen leading to its elimination and the generation of memory cells. Hence SLA plays a crucial role in maintaining overall adaptive immunologic resistance to pathogens. Knowing which SLA alleles that are commonly occurring can be of great importance in regard to future vaccine development and the establishment of immune protection in swine through broad coverage, highly specific, subunit based vaccination against viruses such as swine influenza, porcine reproductive and respiratory syndrome virus, vesicular stomatitis virus, foot-and-mouth-disease virus and others. Here we present the use of low- and high-resolution PCR-based typing methods to identify individual and commonly occurring SLA class I alleles in Danish swine. A total of 101 animals from seven different herds were tested, and by low resolution typing the top four most frequent SLA class I alleles were those of the allele groups SLA-3*04XX, SLA-1*08XX, SLA-2*02XX, and SLA-1*07XX, respectively. Customised high resolution primers were used to identify specific alleles within the above mentioned allele groups as well as within the SLA-2*05XX allele group. Our studies also suggest the most common haplotype in Danish pigs to be Lr-4.0 expressing the SLA-1*04XX, SLA-2*04XX, and SLA-3*04XX allele combination.
We investigated whether IL1RN alleles separately or in combination with MHC class II variants, contribute to susceptibility to SLE and to analysed if IL1RN alleles are markers of disease severity. We investigated 81 patients from a defined area in southern Sweden diagnosed between 1981-1992 and 10 consecutive Caucasian families with multiple cases of SLE. As control group 189 healthy blood donors was used. PCR amplification of defined gene sequences was used in determining the IL1RN polymorphism as well as the MHC class II variants. The IL-1RA levels were measured by an immunoassay. We found an increased frequency of IL1RN*2 in both the epidemiological cohort and in the multicase families (P