In Vivo Induction of Hair Growth by Dermal Cells Isolated from Hair Follicles After Extended Organ Culture

Abstract

Successful hair follicle organ culture has been established for some time, but hair growth in vitro is limited and generally terminates prematurely in comparison with in vivo. The reasons why growth stops in culture are as yet unknown. In this investigation, adult rat vibrissa follicles for which growth in culture is limited to about 10 d, were maintained in vitro for a minimum of 20 d after the hair shaft stopped growing. The pattern of fiber growth and long-term follicle pathology reflected the initial hair cycle stage at the time of isolation. Furthermore, there was evidence that a group of follicles put into culture when in late anagen were attempting to cycle in vitro. Microscopy showed that, in spite of widespread pathologic changes to the follicle epithelium, dermal cells in the follicle showed remarkable resilience. Their viability was confirmed when primary cell cultures were established from isolated dermal tissue. These cells labeled positively for alpha-smooth muscle actin, an established marker of hair follicle dermal cell phenotype in vitro. Moreover, isolated dermal tissue induced hair growth when implanted into inactivated hair follicles in vivo. These data confirm that the cessation in hair growth is not due to a loss of the inductive capacity in the dermal component. Long-term organ culture may provide opportunities to investigate factors that are expressed or lost during hair growth cessation. In addition it may be possible to develop this method further to obtain a reliable and predictable model of hair follicle cycling in vitro.

The Morphology of the Rat Vibrissal Follicle-Sinus Complex Revealed by Three-Dimensional Computer-Aided Reconstruction

“…This observation confirms earlier histologic findings reported by Philpott and Kealey [2000] and Robinson et al [2001]. The possibility of this interesting feature was also proposed by Young and Oliver [1976], who suggested that 2 shafts can be present together in situations in which the regenerating shaft is rapidly growing before the degenerating shaft has left the follicle.…”

“…In other studies, the regenerating shaft was labeled as a 'growing whisker' [Young and Oliver, 1976] and as a 'new fiber' [Philpott and Kealey, 2000]. The degenerating shaft has previously been labeled a 'mature club' [Young and Oliver, 1976], a 'keratinized club hair' [Philpott and Kealey, 2000], and an 'elevated club fiber' [Robinson et al, 2001].…”

Cultured Peribulbar Dermal Sheath Cells Can Induce Hair Follicle Development and Contribute to the Dermal Sheath and Dermal Papilla

“…The induced hair follicles retain morphologic and hair cycle characteristics of the donor hair follicle (Reynolds and Jahoda, 1992). DP may also be placed in culture to increase cell numbers, which may then be implanted to induce hair follicle development (Jahoda and Oliver, 1981;1993;Messenger, 1984;Horne et al, 1986;Reynolds and Jahoda, 1992;Watson et al, 1994;Inamatsu et al, 1998;Robinson et al, 2001). In theory, this simple but e¡ective method of tissue engineering may be employed to treat hair loss due to a variety of diseases, syndromes, and injuries and may provide signi¢cant insights into tissue and organ engineering.…”

Identification of proteins involved in aggregation of human dermal papilla cells by proteomics

“…The tendency of aggregation is one of the significant properties of the DPC, and this property is associated with their biologic function and differentiating state [2][3][4][5][6]. Early passage dermal papilla cells have aggregative behavior and can induce hair growth in vivo, but, upon further culturing, this property is lost (Fig.…”