A Mouse Model for Studying Stem Cell Effects on Regeneration of Hair Follicle Outer Root Sheaths

The study developed an in vitro mouse model to explore how stem cells contribute to the regeneration of hair follicle outer root sheaths (ORS). Researchers used ORSs from 3-day-old Kunming mice and observed their morphological changes over 5 days. They discovered that CD34 and CD200 positive stem cells initiated repair at the periphery of the glass membrane, migrated, and contributed to ORS formation. These stem cells also played a role in forming a new dermal papillary structure containing alpha-smooth muscle actin within the hair follicle matrix. Additionally, neutrophils were found to phagocytose debris and prevent infection, aiding in the regeneration process. The study concluded that isolated hair follicle ORSs can regenerate new structures in vitro, with stem cells and neutrophils playing crucial roles. The model was established using thirty mice, and the study was funded by the National Natural Science Foundation of China with no conflicts of interest reported.