Human leukocyte antigen class II (DRB1 and DQB1) alleles frequencies in patients with various forms of pemphigus among the Russian population

BACKGROUND: Autoimmune bullous dermatoses are known to be the most severe blistering conditions of skin. HLA-DRB1 and DQB1 alleles might play a crucial role in their onset. In pemphigus HLA class II molecules stimulate the division of T helper cells, which in turn stimulate B cells to produce antibodies to epidermal keratinocytes causing acantholysis. The HLA-DRB1 and DQB1 alleles’ frequencies studied in pemphigus in a vast variety of populations worldwide. However, as of yet, this mechanism was not investigated in Russian population. AIM: To estimate the prevalence of the HLA-DRB1 and DQB1 alleles at a low- and high-resolution levels in patients with various forms of pemphigus. We observed 86 patients with pemphigus vulgaris, 13 ― with pemphigus foliaceus, 6 patients with paraneoplastic pemphigus and 92 healthy volunteers. MATERIALS AND METHODS: HLA typing for DRB1 and DQB1 was performed with 50 nanogram DNA extraction and polymerase chain reaction. RESULTS: At a low-resolution level HLA-DRB1*4 and DRB1*14 alleles were statistically significant more frequent in pemphigus vulgaris and pemphigus foliaceus patients compared to those in control subjects, whereas HLA-DRB1*11, DRB*16, and DRB1*3 alleles were more frequent in healthy volunteers. At a high-resolution level, DRB1*04:02 allele was observed to show its statistically significant higher frequency in all variants of pemphigus, including paraneoplastic pemphigus. However, DRB1*14:05 HLA allele was more frequent in pemphigus vulgaris and pemphigus foliaceus patients, whereas DRB1*11:04 one was found to be 3.7 times more frequent in healthy controls. Additionally, at a low-resolution level for HLA-DQB1 alleles no statistically significant results were observed. However, at a high-resolution level the chances for more frequent indication of DQB1*03:02 allele were 7.09 times higher in pemphigus foliaceus group and 2.49 higher in pemphigus vulgaris patients compared to healthy volunteers. Moreover, DQB1*05:03 was identified more frequently in pemphigus vulgaris and paraneoplastic pemphigus groups of patients, whereas DQB1*03:01 allele was shown to be increased in the group of healthy donors. CONCLUSION: HLA-DRB1*4, DRB1*14, DRB1*04:02, DRB1*14:05, DQB1*03:02 and DQB1*05:03 alleles might be considered as the genetic markers for pemphigus vulgaris susceptibility, while HLA-DRB1*11, DRB*16, DRB1*3, DRB1*11:04 and DQB1*03:01 allelic groups appear to be protective for Russian population.