Insulin, S-sulphonate A and S-sulphonate B-chain receptor binding to human cultured lymphocytes

The ability of insulin and the S-sulphonate A and B-chain derivatives to bind to a receptor on cultured human lymphocytes was evaluated. A receptor site for the S-sulphonate A-chain was identified and was strongly influenced by the intact insulin molecule. S-sulphonate A-chain weakly interfered with insulin binding. S-sulphonate B-chain showed no evidence of significant binding and did not interfere with insulin or S-sulphonate A chain binding. 14CO2 production from 14C-1-glucose was stimulated by insulin in cultured lymphocytes and this effect was blunted by S-sulphonate A-chain. The sulphhydryl blocking agent used in the production of insulin A-chain appears to be of critical importance.