Histochemical demonstration of sialomucin in human eccrine sweat glands

Eccrine sweat glands in paraffin sections of human skin fixed in neutral buffered formalin nearly always contained acidic carbohydrate detected by the colloidal iron stain, and to a less extent by Alcian blue 8 GX. Additional histochemical procedures designed to detect sulfated carbohydrates showed none. The acidic carbohydrate demonstrated in eccrine sweat glands was presumed to contain only carboxyl groups. As incubation of tissue sections in neuraminidase abolished stainability of the acidic carbohydrate with colloidal iron, the material removed was considered to be a sialomucin. To the best of our knowledge, the identification of the acidic mucin in human eccrine sweat glands as sialomucin has not been reported previously.