Design of In Vitro Hair Follicles for Different Applications in the Treatment of Alopecia—A Review

The review discussed the advancements in developing in vitro hair follicle (HF) models for treating alopecia, highlighting the challenges due to the cellular complexity and molecular interactions involved. It focused on understanding HFs and their in vitro behavior, emphasizing dermal papilla cells. The paper evaluated the cells, materials, and methods used for in vitro HF growth and presented models and assays for testing active compounds on alopecia and hair growth. Despite progress, achieving fully functional in vitro HFs remained challenging, with unanswered questions about long-term HF cycling and the formation of different hair classes.