Immunolocalization of band 3 protein in normal and cystic fibrosis skin.

Current evidence indicates that the defect in cystic fibrosis (CF) involves chloride transport in various epithelial cells. The sweat gland, one site of altered chloride transport in CF, was examined immunocytochemically for localization of a chloride-channel membrane protein, designated band 3 protein. Immunoreactivity was observed in sweat duct cell membranes of both normal and CF samples, whereas secretory coil regions were entirely unreactive. No difference was observed in the pattern or intensity of immunoreactivity between the two groups at the light microscopic (LM) level of resolution.