Immunohistochemical expression of regulatory T cells (CD4+ CD25+ bright FOXP3+) in pemphigus patients

Background Pemphigus is a series of autoimmune skin disorders caused by IgG. Regulatory T cells (Tregs) are a subset of CD4+ T cells that mostly block pathogenic immune responses mediated by self-reactive cells; therefore, a lack of Tregs or a malfunction in their activity could lead to a loss of tolerance and the development of autoimmunity. Aims To evaluate the expression of lesional and perilesional Treg markers (CD4+ CD25+ bright FOXP3+) in pemphigus patients. Patients and methods Twenty-three pemphigus patients and 20 healthy controls were included in this study. The expression of CD4, CD25, and Foxp(3) was evaluated by immunohistochemistry. Results There was statistically significant increase in CD4+ T lymphocytes in lesional skin of pemphigus compared to perilesional skin and control group (p-value: 0.001). There was statistically significant decrease in CD25(+) and Foxp3(+) cells in lesional skin compared to perilesional and control group (p-value: <0.001, 0.025, respectively). Conclusion The reduction of lesional skin Tregs may play an important role in the pemphigus pathogenesis.