Keratinocyte growth factor-2 (KGF-2) is found in dermal papilla fibroblasts and its receptor, fibroblast growth factor receptor 2 (FGFR2), in the neighboring outer root sheath of keratinocytes. Administration of recombinant human KGF-2 (rhKGF-2) at 10 ng ml(-1) significantly stimulated human hair-follicle cell proliferation in organ culture (26-35%). Thus, rhKGF-2 is a promising therapeutic agent to stimulate human hair growth.