Exploring the Possible Involvement of Skin-Resident Memory T Cells in Refractory Chronic Alopecia Areata

This study explores the role of skin-resident memory T (TRM) cells in refractory chronic alopecia areata (AA). It involved 9 treatment-resistant chronic AA patients and 5 acute AA patients, using CD69 and CD103 markers to identify TRM cells. The analysis revealed an increase in CD8+CD103+ T and CD69+CD103+ T cells with longer disease duration and refractoriness. Additionally, more FABP4+CD103+ T cells were found in chronic and treatment-resistant AA. A case showed that an oral JAK inhibitor improved hair loss and reduced CD103+ cell infiltration. These findings suggest that chronic refractory AA cases have more infiltrating TRM cells, and JAK inhibitors may effectively reduce these cells in such cases.