BACKGROUND Interleukin-3 (IL-3), also referred to as multi-lineage-colony stimulating factor (Multi-CSF), is a 20-26 kDa cytokine produced by activated T-cells and mast cells that has been shown to stimulate renewal of pluripotent hematopoietic stem cells and to be a potent regulator of many hematopoietic cell lineages. IL-3 is capable of inducing the growth and differentiation of multi-potential hematopoietic stem cells, neutrophils, eosinophils, megakaryocytes, macrophages, lymphoid and erythroid cells. IL-3 has been used to support the proliferation of murine cell lines with properties of multi-potential progenitors, immature myeloid as well as T and pre-B lymphoid cells.1 Its role appears to be in stimulating inducible hematopoiesis in response to infections, and it has also been implicated in the pathogenesis of several chronic inflammatory diseases, including asthma, and neurodegenerative disorders, such as multiple sclerosis.2 The effect of IL-3 on human cells is mediated by a receptor system composed of a ligand-specific alpha subunit and a beta subunit (denoted betac) that is also part of the receptor systems for the related cytokines, IL-5 and GM-CSF. Signaling through the betac receptor requires the formation of a high affinity complex involving each cytokine and its respective alpha subunit. Whereas the alpha subunits bind their ligands with low affinity, betac does not measurably bind any of the ligands alone. Upon receptor activation, the cytoplasmic portion of the betac subunit, which lacks any intrinsic kinase activity, initiates a number of signaling pathways including the Janus kinase 2/signal transducers and activators of transcription, phosphatidylinositol 3-kinase, and Ras/mitogen-activated protein kinase pathways.3
1. Metcalf, D. : Nature 339:27-30, 1989
2. Rothenberg, M. E.: J. Clin. Invest. 81:1986-92, 1988
3. Reddy, E.P. et al: Oncogene 19:2532-47, 2000
Products are for research use only. They are not intended for human, animal, or diagnostic applications.
Target Protein Species:
15.6 pg/ml – 1000pg/ml
No detectable cross-reactivity
with any other cytokines
Store at 4°C. Use within 6 months.
ELISA Kits are based on standard sandwich enzyme-linked immunosorbent assay technology. Freshly prepared standards, samples, and solutions are recommended for best results.