Islet cell proteins defined by monoclonal islet cell antibody HISL-19.

A monoclonal islet cell antibody, HISL-19, reactive with human, bovine, and porcine pancreatic islets has been used to identify and characterize a novel group of islet cell proteins (p120, p69, p67, and p56). Besides the islets, HISL-19-reactive antigenic determinants are also expressed on selected cell types, namely, gut endocrine cells, thyroid parafollicular cells (p120), anterior pituitary cells (p40 and p24), specific hypothalamic neuroendocrine cells, and a single layer of large pyramidal cells of the cerebral cortex, thus defining a new family of neuroendocrine molecules.