Gene Expression of CD70 and CD27 Is Increased in Alopecia Areata Lesions and Associated with Disease Severity and Activity

Background. Alopecia areata (AA) is an acquired hair loss disorder induced by a cell-mediated autoimmune attack against anagen hair follicles. CD27-CD70 is a receptor-ligand complex which enhances T helper and cytotoxic T cell activation, survival, and proliferation. The overstimulation of this complex can lead to a lack of tolerance and the development of autoimmunity. Objectives. This study aimed to assess the gene expression of CD27 and CD70 in patients with AA. Methods. CD70 and CD27 mRNA expressions were evaluated by a quantitative real-time polymerase chain reaction in scalp biopsies from 40 AA patients (both AA lesions and non-lesional areas) and 40 healthy controls (HCs). The Severity of Alopecia Tool (SALT) score was used to assess AA severity. Patients were evaluated for signs of AA activity, including a positive hair pull test and dermoscopic features of black dots, broken hairs, and tapering hairs. Results. The gene expression of CD70 and CD27 was significantly higher in AA lesions than in non-lesional areas (p