Hair Follicle Stem Cells in the Pathogenesis of Primary Cicatricial Alopecia

The study investigated the role of epithelial hair follicle stem cells in the scarring process of primary cicatricial alopecia (PCA) by examining skin biopsies from 40 patients with various forms of PCA. The research focused on the expression of cytokeratin 15 (CK15), a marker for hair follicle stem cells, and its correlation with inflammatory cell infiltrate. Results showed that CK15 expression was absent in scarred PCA and weak or absent in cases of severe inflammation, suggesting damage to stem cells or their differentiation for repair. This damage to follicular stem cells might explain the irreversible alopecia and scarring characteristic of PCA.