Researchers at the University of Southern California (USC) School of Medicine have pinpointed the biological processes that lead to the differentiation of skin stem cells into follicles that grow hair. As people age, the ability to regenerate skin cells declines and therefore, the follicles produce less and less hair. Utilizing a combination of bioinformatics and molecular screenings, the researchers studied the differentiation of stem cells into hair follicles of newborn mice, honing in on genetic factors and environmental cell signals this process entails. The process was then successfully implemented when applied to adult mice that lacked hair by introducing the necessary factors that signal stem cells to differentiate into organoids that will grow hair.
Researchers at UT Southwestern Medical Center have identified a gene that directs the production of a stem cell factor (SCF) and a protein, which are both essential for hair growth and pigmentation. Stem cells are concentrated in the skin around hair follicles, and when both the protein and the SCF are active, they move up from the bulb of the follicles to produce pigmented hairs. The genes responsible for the production of the KROX20 protein and the SCF were discovered by working backwards, turning off the gene and observing, in mice subjects, that no pigmentation was present in the hairs and that the subjects became bald.