Tp63-Expressing Adult Epithelial Stem Cells Cross Lineage Boundaries Revealing Latent Hairy Skin Competence

The study revealed that adult epithelial stem cells expressing the transcription factor Tp63 from various non-skin tissues have the inherent potential to contribute to hair follicles, sebaceous glands, and epidermis when transplanted into a newborn skin microenvironment. This finding challenges the previously held belief that only embryonic epidermal cells are responsive to hair follicle morphogenetic signals. The researchers performed 156 transplantations of epithelial cells from tissues such as the cornea, esophagus, vagina, bladder, and prostate of adult rodents into the skin of newborn mice, with success rates ranging from 12.25% to 100% depending on the tissue of origin. Genetic analyses indicated a switch in gene expression towards hair follicle characteristics post-transplantation. The study suggests that Tp63-expressing epithelial stem cells retain a memory of their origin, which influences their plasticity and response to environmental cues, and that they possess latent skin competence, potentially useful for tissue regeneration and cross-lineage differentiation of adult stem cells.