Reprogramming of three-dimensional microenvironments for <i>in vitro</i> hair follicle induction

The study demonstrated that reprogramming three-dimensional microenvironments could induce hair follicle formation in vitro by controlling interactions between epithelial and mesenchymal cells. This approach led to the creation of hair follicloids, which efficiently produced hair shafts up to 3 mm long. The model successfully replicated hair follicle morphogenesis, including melanosome production and transport, and upregulated typical trichogenic signaling pathways. This in vitro model provided insights into hair follicle induction and could be used to evaluate hair growth, drug effects, and model gray hair, potentially informing new treatment strategies.