Bacterial overexpression of the human interleukin-2 in insoluble form via the pET Trx fusion system

Selection of a system for successful recombinant protein production is important. The aim of this study was to produce high levels of human interleukin-2 (hIL-2) in soluble form. To this end, the pET32a vector in Escherichia coli BL21 (DE3) was used as an expression system, since it was previously used for the production of mouse IL-2 in soluble form. The results indicated that contrary to expectations, the expressed protein was in the form of inclusion bodies and perhaps amino acid differences between human and mouse IL-2 should be determinant. The hIL-2 protein is a small peptide, therefore its recovery as a biologically functional protein by the process of refolding may be feasible and could lead to high yields at the industrial scale.