Skin γδ T Cell Subsets Have Distinct Functions in Alopecia Areata

The study investigates the role of γδ T cells in the pathogenesis of alopecia areata, an autoimmune disease causing patchy hair loss. Researchers from California State University San Marcos analyzed single-cell RNA sequencing data from mouse and human skin to identify gene expression changes in γδ T cells during the disease. They found that dermal Vγ6Vδ1 T cells upregulate IL17a, similar to psoriasis, while Vγ4Vδ1 T cells increase genes related to T cell recruitment, such as CXCL10, suggesting they amplify the Th1 response. Epidermal γδ T cells upregulate inflammation-related genes, including STAT1 and SCA-1/Ly6a, with STAT1 regulating SCA-1/Ly6a expression and IFN responses. These findings, validated in C3H/HeJ mice, highlight the distinct roles of γδ T cell subtypes in alopecia areata, with ongoing examinations in human skin.