ASSOCIATION OF VERSICAN WITH DERMAL MATRICES AND ITS POTENTIAL ROLE IN HAIR FOLLICLE DEVELOPMENT AND CYCLING

Versican is a member of the group of aggregating proteoglycans involve d in matrix assembly and structure and in cell adhesion. We examined c hanges in the distribution of versican in mammalian skin, with emphasi s on hair follicle development and cycling, In adult human skin, immun ostaining for versican appeared predominantly in the dermis, with inte nse staining of the reticular dermis. Weak staining was observed at th e dermoepidermal junction and the connective tissue sheath of hair fol licles, Versican expression was also noted in the reticular dermis of rat skin, within dermal papillae, and possibly associated with follicl e basement membranes, During mouse hair follicle development, versican was not expressed until the hair follicles were beginning to produce fibers. With follicle maturation, versican expression intensified in t he dermal papillae, reaching a maximum at the height of the growth pha se (anagen), after which it diminished as the end of this phase approa ched, Versican immunoreactivity in the papillae decreased further duri ng catagen and was absent from these structures during telogen, Howeve r, intense staining for versican was then observed in the neck regions of telogen follicles, As the follicles entered the next hair cycle, v ersican disappeared from the necks and was again seen in the dermal pa pillae when follicles began producing fibers. This type of expression continued throughout subsequent hair cycles and is unlike any other de rmal papilla component, The results of this study are consistent with a distinct supportive role for versican in the follicle matrices durin g hair follicle morphogenesis and cycling.