Abstract: Methods and compositions for increasing trichogenicity of cells in culture are provided. One embodiment provides culturing dissociated mammalian dermal cells in vitro in the presence of an effective amount of one or more sonic hedgehog (Shh) pathway agonists to increase the trichogenicity of the dissociated mammalian dermal cells compared to untreated dissociated mammalian dermal cells. The cell culture optionally includes epidermal cells. Preferred Shh agonists include, but are not limited to CUR-0236715 and CUR-0201365 available from Curis, Inc. Trichogenicity is measured using the Aderans Hair Patch Assay™. The cultured dermal cells can be maintained in culture in the presence of the one or more Shh agonists for at least 1 to 7 or more days prior to harvest. The treated, cultured dermal cells can be used to treat hair loss in a mammalian subject, preferably a human, by implanting them in an effective amount to induce hair follicle formation.