转化生长因子β(TGFβ)是一种双功能生长调节剂,但对多数细胞(包括上皮细胞、内皮细胞及造血祖细胞等)充当生长抑制剂。至今已有5种TGFβ,即TGFβ1～5。TGFβ1首先获得鉴定和克隆化,因此,本文的TGFβ是专指TGFβ1。 TGFβ的结构:TGFβ是双硫键联结的二聚体,分子量为25000,每条多肽各12500。TGFβ前体有390个氨基酸,在C端第112个氨基酸处裂解。TGFβ是碱性蛋白,对热、酸、碱有抗力。二聚体结构是其生物活性所必需的。人血小板仅含TGFβ1。 TGFβ的生成和非活性型:许多组织和培养细胞能产生TGFβ,最丰富的来源是血小板和骨。Niitsu Transforming growth factor beta (TGFβ) is a bifunctional growth regulator that acts as a growth inhibitor for the majority of cells, including epithelial cells, endothelial cells, and hematopoietic progenitor cells. Up to now, five kinds of TGFβ, TGFβ1 ~ 5 have been reported. TGFβ1 was first identified and cloned, and TGFβ herein specifically refers to TGFβ1. Structure of TGFβ: TGFβ is a disulfide-linked dimer with a molecular weight of 25,000 and 12,500 each. The TGFβ precursor is 390 amino acids and cleaves at the C-terminal 112th amino acid. TGFβ is a basic protein that is resistant to heat, acids and alkalis. The dimeric structure is necessary for its biological activity. Human platelets contain only TGFβ1. TGFβ Production and Inactivation: Many tissues and cultured cells produce TGFβ, the most abundant source of which is platelets and bone. Niitsu