Description
Interleukin-7 (IL-7) is a stromal cell-derived growth factor produced in bone marrow, thymus and spleen. IL-7 promotes the proliferation of precursor B-cells, thymocytes, T cell progenitors and mature CD4+ and CD8+ T cells. IL-7 can induce the formation of lymphokine-activated killer (LAK) cells as well as the development of cytotoxic T lymphocytes (CTL). Recently, IL-7 was also shown to induce the V(D)J rearrangement of the T cell receptor b gene in mouse fetal thymocytes. Among myeloid lineage cells, IL-7 can up-regulate the production of pro-inflammatory cytokines and stimulate the tumorocidal activity of monocytes/macrophages. IL-7 binds to a high affinity receptor formed by the ligand binding subunit (IL-7 R) and the g chain of the IL-2 receptor. Mouse IL-7 cDNA encodes a precursor protein of 154 amino residues containing a 25 amino acid residue signal peptide. The methionyl form of recombinant mouse IL-7 contains 130 amino acid residues and has a molecular mass of approximately 15 kDa