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

The review discussed advancements in developing in vitro hair follicle (HF) models for treating alopecia, emphasizing the complexity of creating functional models due to intricate cellular interactions. It highlighted the importance of 3D models over 2D ones, as they better mimic in vivo conditions, and explored techniques like 3D printing and the use of materials such as silk fibroin protein. Dermal papilla cells (DPCs) were identified as crucial for HF growth, requiring specific signaling pathways like WNT and BMP for maintaining regenerative properties. The review noted the potential of in vitro models in reducing animal testing and evaluating hair growth treatments, while also addressing challenges in replicating the human hair growth cycle. Future research was suggested to focus on enhancing these models by incorporating stem cell niches and achieving single-cell resolution to better replicate natural HFs.