M-CSF/CSF1, Human, HEK293 Cells,Tag Free

Macrophage Colony Stimulating Factor(M-CSF), also known as CSF-1, is a four-alpha -helical-bundle cytokine that is the primary regulator of macrophage survival, proliferation and differentiation (1-3). M-CSF is also essential for the survival and proliferation of osteoclast progenitors (1, 4). M-CSF also primes and enhances macrophage killing of tumor cells and microorganisms, regulates the release of cytokines and other inflammatory

modulators from macrophages, and stimulates pinocytosis (2, 3). M-CSF increases during pregnancy to support implantation and growth of the decidua and placenta (5). Sources of M-CSF include fibroblasts, activated macrophages, endometrial secretory epithelium, bone marrow stromal cells and

activated endothelial cells (1-5). The M-CSF receptor (c-fms) transduces its pleotropic effects and mediates its endocytosis. M-CSF mRNAs of varioussizes occur (3-9). Full length human M-CSF transcripts encode a 522 amino acid (aa) type I transmembrane (TM) protein with a 464 aa extracellular

region, a 21 aa TM domain, and a 37 aa cytoplasmic tail that forms a 140 kDa covalent dimer. Differential processing produces two proteolytically

cleaved, secreted dimers. One is an N- and O- glycosylated 86 kDa dimer, while the other is modified by both glycosylation and chondroitin-sulfate

proteoglycan (PG) to generate a 200 kDa subunit. Although PG-modified M-CSF can circulate, it may be immobilized by attachment to type V collagen

(8). Shorter transcripts encode M-CSF that lacks cleavage and PG sites and produces an N-glycosylated 68 kDa TM dimer and a slowly produced 44

kDa secreted dimer (7). Although forms may vary in activity and half-life, all contain the N-terminal 150 aa portion (10）.

1. Pixley, F.J. and E.R. Stanley (2004) Trends Cell Biol. 14:628.

2.Chitu, V. and E.R. Stanley (2006) Curr. Opin. Immunol. 18:39.

3. Fixe, P. and V. Praloran (1997) Eur. Cytokine Netw. 8:125.

4. Ryan, G.R. et al. (2001) Blood 98:74.

5. Makrigiannakis, A. et al. (2006) Trends Endocrinol. Metab. 17:178.

6. Nandi, S. et al. (2006) Blood 107:786.

7. Rettenmier, C.W. and M.F. Roussel (1988) Mol. Cell Biol. 8:5026. 

8. Suzu, S. et al. (1992) J. Biol. Chem. 267:16812.

9. Manos, M.M. (1988) Mol. Cell. Biol. 8:5035.

10. Koths, K. (1997) Mol. Reprod. Dev. 46:31.