The present invention is directed to an in vitro method for promoting proliferation, survival, and/or differentiation of K14+, K17+ nail stem cells (NSCs). The instant methods may be used to generate an expanded population of K14+, K17+ NSCs in vitro and expanded NSC populations in which a Wnt pathway is activated are envisioned as therapeutic agents. Methods for screening to identify agents capable of modulating K14+, K17+ NSC proliferation, survival, and/or differentiation are also encompassed herein, as are isolated, pure populations of homogeneous K14+, K17+ NSCs.