Receptor binding properties and biologic activity in vitro of biosynthetic human insulin

The interaction of biosynthetic human insulin with human cultured lymphocytes, human circulating erythrocytes, and isolated rat fat cells was examined. The binding of the biosynthetic insulin to human cells was identical to that of native human or pork insulins, with respect to affinity, kinetics of association and dissociation, negative cooperativity, and downregulation of lymphocyte receptors. The biosynthetic insulin also had equal potency in stimulating the incorporation of [3H]-glucose into the lipids of isolated rat fat cells. These data suggest that the structure of the biosynthetic insulin has been integrally reconstituted.