Epidermal γδ T Cells, CD8 T Cells, and Macrophages Are Increased in Number in Alopecia Areata and Express BST2 as Part of an Interferon-Driven Antiviral Gene Signature
June 2025
in “
bioRxiv (Cold Spring Harbor Laboratory)
”
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Studysummary This study found that in alopecia areata, epidermal γδ T cells and macrophages contribute to the disease alongside CD8 T cells, with the expression of BST2 marking interferon-driven immune activation in both mouse and human skin, which decreases following treatment with the JAK inhibitor tofacitinib. Our plain-language summary of this paper — not a Tressless recommendation.
This study investigates the role of various immune cells in alopecia areata, an autoimmune disorder causing hair loss. The research highlights the involvement of epidermal γδ T cells and macrophages, alongside the known role of CD8 T cells, in the disease's pathogenesis. Using single-cell RNA sequencing data from mice, the study shows that these cells express BST2, an interferon-stimulated antiviral protein, which is elevated in alopecia areata and decreases with JAK inhibitor treatment. The findings suggest that BST2 is a marker of immune activation in alopecia areata, emphasizing the contribution of epidermal γδ T cells to the condition.
