Immunopathogenesis of Primary Cicatricial Alopecia

The study investigated the immunopathogenesis of Lichen Planopilaris (LPP), a form of primary cicatricial alopecia (PCA) characterized by scarring hair loss. It found that the collapse of immune privilege in hair follicles led to irreversible damage to epithelial stem cells, preventing hair regeneration. The research identified increased degranulated mast cells and reduced resident macrophages in LPP hair follicles, suggesting their roles in the disease. Additionally, evidence of epithelial-mesenchymal transition (EMT) in the epithelial stem cell zone was observed, contributing to scarring. These findings aimed to enhance understanding and management of PCA, although no causal therapy was available at the time.