Immunological and immuno-fluorescent studies on keratin of the hair follicle.

Keratins from the differentiating cortical cells of the guinea-pig hair follicle have been studied by immunological and immunofluorescent procedures. Antisera were prepared to the unfractionated keratin proteins from the follicle and the specificity of these antisera examined by lmmunodifTusion and lmmunoelectrophoresis. The major follicle antigens were the 'lowsulphur' keratins, and the antibodies were specific for these and related a-keratins. Use of the precipitin reaction as a quantitative immunoassay for follicle keratins has been demonstrated. The fluorescent antibody technique has been applied to the hair follicle and the follicle antigens have been localized by this procedure in the cytoplasm of the developing cortical cells. By this technique keratin could not be detected in the prohferative cells of the bulb region of the follicle supporting the view that keratin synthesis begins only when the cells enter the upper bulb region of the follicle.