Keratin 79 Identifies a Novel Population of Migratory Epithelial Cells That Initiates Hair Canal Morphogenesis and Regeneration

In the 2013 study, researchers identified Keratin 79 (K79) as a marker for a previously unknown population of migratory epithelial cells essential for hair follicle lumen formation during morphogenesis and regeneration. These K79-positive cells originate from the hair germ and migrate outward to form the hair canal, a process that occurs both in embryonic development and adult hair regeneration. The study also found that the infundibulum of the hair follicle is maintained by upward-moving Lrig1-positive stem cell-derived progeny, and disruptions in this area are linked to acne progression. Notch signaling was found to be active in the infundibulum but not necessary for K79 expression. The research provides new insights into the cellular dynamics and molecular mechanisms of hair follicle development and suggests a potential connection between K79-positive cells and acne pathology. Further research is needed to fully understand the regulation of K79 and the origin of these cells.