Recombinant IL31 is a bioactive protein intended for use in cell culture applications. IL31 is primarily associated with activated T cells and expressed by Th2 rather than Th1 cells. IL31 signals via IL31RA and the oncostatin M receptor. IL31 signaling has been shown to involve the Jak/STAT pathway, the PI3 kinase/AKT cascade, and MAP kinase pathway.