Stem cell factor (SCF), otherwise known as KIT ligand or Steel factor[1],is a cytokine which binds CD117 (c-Kit). SCF is also known as "steel factor" or "c-kit ligand". SCF exists in two forms, cell surface bound SCF and soluble (or free) SCF. Soluble SCF is produced by the cleavage of surface bound SCF by metalloproteases.

SCF is a growth factor important for the survival, proliferation, and differentiation of hematopoietic stem cells and other hematopoietic progenitor cells. One of its roles is to change the BFU-E(burst-forming unit-erythroid) cells, which are the earliest erythrocyte precursors in the erythrocytic series, into the CFU-E (colony-forming unit-erythroid) . SCF, along with bFGF (basic fibroblast growth factor) and LIF (lymphocyte inhibitory factor), prevents spontaneous differentiation of primitive embryonic stem cell in cell culture[1].

Ancestim is a recombinant form of SCF.

干细胞因子（SCF）,或者所知的KIT配体或Steel因子[1]，是一种绑定CD117（C-kit）的细胞因子。SCF存在两种形式，细胞表面绑定的SCF和可溶性（或游离的）SCF。可溶性SCF通过金属蛋白酶作用由表面绑定SCF分裂而成。

SCF对于造血干细胞和其它造血祖细胞的生存、增生和分化是一种重要的生长因子。其中一个重要作用是使BFU-E（爆式红细胞集落形成单元）细胞（在红细胞系中是一种早期前驱红细胞）向CFU-E（红细胞集落形成单元）细胞转变。SCF，伴随bFGF（碱性成纤维细胞生长因子）和LIF（淋巴细胞抑制因子），在细胞培养中阻止原始胚胎干细胞的自发性分化。[1]

安塞司亭(ancestim)是SCF的重组形式。

References（摘自）

^ a b Freshney, Ian R. Culture of Animal Cells: A manual of basic technique. John Wiley & Sons, Inc., Hoboken, New Jersey. ISBN 13 978-0-471-45329-1

^ da Silva MG, Pimentel P, Carvalhais A, et al (2004). "Ancestim (recombinant human stem cell factor, SCF) in association with filgrastim does not enhance chemotherapy and/or growth factor-induced peripheral blood progenitor cell (PBPC) mobilization in patients with a prior insufficient PBPC collection". Bone Marrow Transplant. 34 (8): 683–91. doi:10.1038/sj.bmt.1704602. PMID 15322567