Basement Membrane Changes in Lichen Planopilaris

The study investigated basement membrane zone (BMZ) alterations in lichen planopilaris (LPP), an inflammatory disease causing cicatricial alopecia, using skin biopsies from 6 LPP patients and 6 controls. Immunohistochemistry revealed significant differences in the localization and staining of hemidesmosome, laminin, and collagen components in inflamed follicular epithelium compared to uninvolved areas. Hemidesmosome-associated complexes were weak and discontinuous, while laminin-5, type IV collagen, and type VII collagen showed disrupted, non-linear expression with projections into the dermis. These BMZ changes likely contributed to abnormal follicular healing, leading to irreversible hair loss and scarring in LPP.