Islet amyloid in Type 2 (non-insulin-dependent) diabetes is related to insulin

Amyloid deposition is the most typical islet alteration in Type 2 (non-insulin-dependent) diabetes. In the present study we show by immunohistochemistry that the amyloid reacts with an antiserum against insulin B chain. Islet amyloid was also purified, dissolved in guanidine-HCl and gel filtered on a Sepharose 6B column. Immunization of a guinea pig with a high molecular weight fraction from this gel filtration resulted in an antiserum with insulin-binding capacity. This binding was partially blocked with pure insulin B chain. The results indicate that islet amyloid contains insulin B chain and that the amyloid is a product of the islet B cells. Thus the study support previous morphological studies.