OSM Protein

Interleukin-2 (IL-2) is an interleukin, a type of cytokine signaling molecule in the immune system. It regulates the activities of white blood cells (leukocytes, often lymphocytes) that are responsible for immunity. IL-2 is part of the body’s natural response to microbial infection, and in discriminating between foreign (\”non-self\”) and \”self\”. IL-2 mediates its effects by binding to IL-2 receptors, which are expressed by lymphocytes. The major sources of IL-2 are activated CD4+ T cells and activated CD8+ T cells.IL-2 has essential roles in key functions of the immune system, tolerance and immunity, primarily via its direct effects on T cells. In the thymus, where T cells mature, it prevents autoimmune diseases by promoting the differentiation of certain immature T cells into regulatory T cells, which suppress other T cells that are otherwise primed to attack normal healthy cells in the body.Oncostatin M (OSM) was initially identified as a polypeptide cytokine which inhibited the in vitro growth of cells from melanoma and other solid tumors. OSM shows significant similarities in primary amino acid sequence and predicted secondary structure to leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF), granulocyte colony-stimulating factor (G-CSF), interleukin 6 (IL-6), and interleukin 11 (IL-11). The antiproliferative activity of oncostatin M for some cell lines is synergised by TGF-beta and IFN-gamma. It promotes the growth of human fibroblasts, vascular smooth muscle cells, and some normal cell lines. Other OSM-mediated activities reported to date include: stimulation of plasminogen activator activity in cultured bovine aortic endothelial cells; regulation of IL-6 expression in human endothelial cells; and stimulation of LDL uptake and up-regulation of cell surface LDL receptors in HepG2 cells.