ANTIBODIES AGAINST THE COMPONENT POLYPEPTIDE CHAINS OF BOVINE INSULIN.

Antibodies were produced in guinea pigs against A and B chains of bovine insulin; the chains were prepared by cleavage of all the disulfide bonds with sulfite. Antibodies against A chain reacted with A chain, but not with B chain or native insulin. Antibodies against B chain reacted strongly with both B chain and insulin, but not with A chain. Antibodies against insulin reacted strongly with insulin, weakly with B chain, and not at all with A chain. The results indicate that the insulin-reactive antibodies in antiserums to B chain and to insulin differ and are directed to differing individual antigenic regions of the insulin molecule.