Regulatory T cells in skin lesions and blood of patients with bullous pemphigoid

Background Although regulatory T cells (Tregs) are affected in several autoimmune skin diseases, only two studies have been performed in patients with bullous pemphigoid (BP) with contrasting results. Objective To characterize Tregs and to determine the serum levels of regulatory cytokines in patients with BP. Methods In BP lesional skin, immunohistochemistry and confocal microscopy were performed for CD4+, CD25+, forkhead/winged helix transcription factor (FOXP3)+, transforming growth factor (TGF)‐β+ and interleukin (IL)‐10+ cells. In addition, the number of CD4+CD25++FOXP3+ Tregs in peripheral blood was assessed by flow cytometry, and the levels of TGF‐β and IL‐10 were determined in serum samples by enzyme‐linked immunosorbent assay before and after steroid therapy. Controls included patients with psoriasis, atopic dermatitis (AD) and healthy donors. Results The frequency of FOXP3+ cells was significantly reduced in skin lesions from patients with BP (P