重组人肿瘤坏死因子-α

Tumor necrosis factor alpha (TNF-α) is produced by neutrophils, activated lymphocytes, macrophages, NK cells, LAK cells, astrocytes endothelial cells, smooth muscle cells and some transformed cells. TNF-α occurs as a secreted, soluble form and as a membrane-anchored form, both of which are biologically active. The naturally-occurring form of TNF-α is glycosylated, but non-glycosylated recombinant TNF-α has comparable. The biologically active native form of TNF--α is reportedly a trimer. 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.

肿瘤坏死因子α（TNF-α）是一种多功能细胞因子，可由中性粒细胞、活化淋巴细胞、巨噬细胞、自然杀伤（NK）细胞、淋巴因子激活杀伤（LAK）细胞、星形胶质细胞、内皮细胞、平滑肌细胞以及某些转化细胞分泌产生。TNF-α以分泌型可溶性形式和膜结合形式两种状态存在，且两种形式均具有生物学活性。天然TNF-α为糖基化蛋白，而非糖基化重组TNF-α也具有与天然蛋白相近的生物学活性。据报道，天然TNF-α的活性形式主要以三聚体结构存在。人源与小鼠源TNF-α在氨基酸序列上具有约79%的同源性，并存在一定的种属间交叉反应性。目前已鉴定出两种TNF-α受体，几乎所有已研究的细胞类型均表达其中一种或两种受体。