肿瘤坏死因子α (TNF-α),又称Cachectin,是肿瘤坏死因子家族中最知名的成员,可导致细胞死亡。该蛋白由中性粒细胞、活化淋巴细胞、巨噬细胞、NK细胞、LAK细胞、星形胶质细胞、内皮细胞、平滑肌细胞和一些转化细胞产生。TNF-α的自然形式是糖基化的,但非糖基化的重组TNF-α具有类似的生物活性。人和鼠TNF-α在氨基酸水平上显示了约79%的同源性,并在两种物种之间显示了交叉反应性。已经描述了TNF-α的两种受体类型,几乎所有研究的细胞类型都显示存在一种或两种受体类型。重组小鼠TNF-α是一条含有157个氨基酸的非糖基化多肽链 。
Purity
>97% (SDS-PAGE; HPLC). Purity is greater than 97% as determined by SEC-HPLC and reducing SDS-PAGE.
Additional sequence information
NP_038721. Mature protein; soluble form.
Function
Cytokine that binds to TNFRSF1A/TNFR1 and TNFRSF1B/TNFBR. It is mainly secreted by macrophages and can induce cell death of certain tumor cell lines. It is potent pyrogen causing fever by direct action or by stimulation of interleukin-1 secretion and is implicated in the induction of cachexia, Under certain conditions it can stimulate cell proliferation and induce cell differentiation.
Post-translational
The soluble form derives from the membrane form by proteolytic processing. The membrane form, but not the soluble form, is phosphorylated on serine residues. Dephosphorylation of the membrane form occurs by binding to soluble TNFRSF1A/TNFR1. O-glycosylated; glycans contain galactose, N-acetylgalactosamine and N-acetylneuraminic acid.
Tumor necrosis factor alpha (TNF-α), also called Cachectin, is the best-know member of the TNF-family, which can cause cell death. This protein is produced by neutrophils, activated lymphocytes, macrophages, NK cells, LAK cells, astrocytes endothelial cells, smooth muscle cells and some transformed cells. The naturally-occurring form of TNF-α is glycosylated, but non-glycosylated recombinant TNF-α has comparable biological activity. Human and murine TNF-α show approximately 79 % homology at the amino acid level and cross-reactivity between the two species. Two types of receptors for TNF-α have been described and virtually all cell types studied show the presence of one or both of these receptor types. The recombinant Murine TNF-α is a non-glycosylated polypeptide chain containing 157 amino acids