To raise new antibodies against the cells contained in human hair follicles, we immunized mice with a mixture of primary cultured human embryogenic keratinocytes thought to contain very immature keratinocytes, as antigen. Using a monoclonal antibody (MAb) producing technique, we obtained two MAbs, which recognize a specific portion of the hair follicle. MAb-8G2 was specific to the companion layer between the inner and outer root sheath of the follicle. This pattern of recognition was quite similar to the expression pattern of K6hf protein, a human hair follicle-specific type II cytokeratin. MAb-sDP showed unique recognition. Immunohistochemistry indicated that MAb-sDP specifically recognized the cells surrounding the dermal papilla (DP). These cells are possibly the germ line cells of hair matrix.