Association of Human Endogenous Retrovirus-W (HERV-W) Copies with Pemphigus Vulgaris

Background Pemphigus is classified as a group of chronic, recurrent, and potentially fatal bullous autoimmune diseases that leads to blisters and skin lesions resulting from IgG antibodies and the loss of cellular connections in the epidermis. Human endogenous retrovirus (HERV) sequences and their products (RNA, cytosolic DNA, and proteins) can modulate the immune system and contribute to autoimmunity. The extent to which, HERV-W env copies may be involved in the pathogenesis of pemphigus remains to be elucidated. Aim This study aimed to comparatively evaluate the relative levels of HERV-W env DNA copy numbers in the peripheral blood mononuclear cells (PBMCs) of pemphigus vulgaris patients and healthy controls. Methods Thirty-one pemphigus patients and the corresponding age- and sex-matched healthy controls were included in the study. The relative levels of HERV-W env DNA copy numbers were then evaluated by qPCR using specific primers, in the PBMCs of the patients and controls. Results Our results indicated that relative levels of HERV-W env DNA copy numbers in the patients were significantly higher than that in the controls (1.67 +/- 0.86 vs. 1.17 +/- 0.75; p = 0.02). There was also a significant difference between the HERV-W env copies of male and female patients (p = 0.001). Furthermore, there was no relationship between the HERV-W env copy number and disease onset (p = 0.19). According to the obtained data, we could not find any relationship between the HERV-W env copy number and serum Dsg1(p=0.86) and Dsg3 (p=0.76) levels. Conclusion Our results indicated a positive link between the HERV-W env copies and pathogenesis of pemphigus. The association between clinical severity score and HERV-W env copies in the PBMCs as a biomarker for pemphigus needs further studies.