Extracellular Matrix as a Regulator of Epidermal Stem Cell Fate

The document reviews the critical role of the extracellular matrix (ECM) in the fate of epidermal stem cells, especially within the hair follicle stem cell niche. It explains that the ECM, particularly through the basement membrane, is essential for maintaining stem cell quiescence, self-renewal, and homeostasis, and it influences cell division and differentiation. The review points out that the destruction of ECM components can disrupt epidermal stem cell morphogenesis and homeostasis. It also discusses the molecular structure of the ECM and the development of in vitro systems that mimic the ECM to maintain stem cells, which could advance regenerative medicine. The document emphasizes the importance of understanding the signals within the stem cell niche that regulate stem cell behavior, which has implications for tissue engineering and understanding disease mechanisms, such as tumor proliferation. It also notes that matrix metalloproteinases (MMPs) are crucial for hair regrowth, and changes in ECM components can affect stem cell properties during embryogenesis, in response to pathogens, and in various pathological conditions. The document underscores the complexity of ECM-epidermal stem cell interactions and the need for further research to fully understand these mechanisms.