Production of interleukin-12 as a self-processing 2A polypeptide

Interleukin-12 (IL-12) is a heterodimeric cytokine composed of two disulfid e-linked subunits (p40 and p35) encoded by separate genes. We used the appa rent autocleavage property of a 2A peptide from the foot-and-mouth disease virus (FMDV) to express bovine (Bo) IL-12 as a self-processing polypeptide (p402Ap35). We demonstrate that 2A will mediate the cleavage of p402Ap35 in to two separate subunits in a manner similar to that observed during the pr ocessing of the FMDV polypeptide. Furthermore, this 2A polypeptide encoded a functional heterodimer, which elicited activities associated with IL-12 i n other species. We propose that this strategy of self-processing polypepti des may be used in many applications where the coordinated and stoichiometr ic expression of complex proteins is required.