Proinflammatory cytokines of the interleukin-36 (IL-36) family are involved in pathogenesis of different skin diseases in human and mice. Administration of exogenous IL-36 receptor antagonist (IL-36Ra) could be an approach to therapy of different dermatitises. For its full biological activity IL-36Ra require the cleavage of N-terminal methionine residue. We created 3 Escherichia coli strains producing IL-36Ra coexpressed with E. coli methionine aminopeptidase under control of different promoters. To test biological activity of IL-36Ra from different strains we transfected the A549 cell line with plasmid carrying IL-36 receptor gene (IL1RL2). These cells respond to IL-36g treatment with production of IL-8 which can be quantified with ELISA. IL-36Ra treatment disrupts IL-36 receptor activation by IL-36g and production of IL-8. Using this system we proved that IL-36Ra from all 3 production strains is fully biologically active.