Expression of mature human interleukin 2 and its derivatives in Escherichia coli and comparison of their biological activity in vitro.

Abstract

A mature human interleukin 2 (hIl-2) and its derivatives that lacked the N-terminal portion were expressed in Escherichia coli under the control of the phage λ PL promoter. They accumulated in the form of insoluble inclusion bodies and accounted for about 30% of the total cellular protein. The mature hIl-2 and its derivatives were further purified and their in vitro biological activity was compared in an Il-2 microassay. The results suggested that the hIl-2 derivatives without the N- terminal three or five amino acids were as active as intact hIl-2 and that those without the N- terminal eight or nine amino acids were less active than the intact form.