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 immunohistochemistry on skin biopsies from 6 LPP patients and 6 controls, researchers found 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, and the expression of laminin-5, type IV collagen, and type VII collagen was disrupted, with projections into the dermis. These BMZ changes may contribute to abnormal healing and irreversible hair loss in LPP.