Oncostatin M (OSM)

Oncostatin M (OSM) is a member of the IL-6 family of cytokines that is produced primarily by activated T cells and macrophages. OSM induces fibroblast proliferation, inhibits tumor cell proliferation, and plays a role in immune regulation. Mouse OSM binds to the OSM receptor β (OSMRβ) which forms a heteromeric complex with the common IL-6 family receptor subunit, gp130. In contrast, human OSM binds to two distinct receptor complexes, the OSMRβ/gp130 and LIFRβ/gp130 complexes. The ability of human OSM to bind to two receptors may explain the overlapping and distinct activities of human OSM and LIF. OSM induces the activation the JAK2, STAT3, and ERK1/2 pathways.