Morphogenetic Mechanisms in the Cyclic Regeneration of Hair Follicles and Deer Antlers from Stem Cells

Figure 4

Stem-cell lineage tracing using an exogenous gene LacZ. (a)–(c) Reproduced with permission from [18, Figures 3A, 3D, and 3F, resp.]. Chimeric HF that was created by a wild type HF having its bulge being replaced with the one that expresses LacZ. Note that the β-galactosidase-positive cells gradually moved down the HF shaft, reaching the bulb region at the sixth week (a), the tip of the bulb at the seventh week (b), and the entire HF at the tenth week (c). (d)–(g) Reproduced with permission from [19, Figures 3F, 3G and 3H, resp.]. Histological sections from the four areas of a growing antler, which was formed from AP of the presumptive AU region where a small population of AP cells was labelled by LacZ gene. Note that β-galactosidase-positive cells were detected in every mesenchyme-derived tissue component of the antler (excluding the skin) including reserve mesenchyme (d), precartilage (e), cartilage (f), and lamellar bone (g).