Chan G, Ochi A
Autoimmunity Group, John P. Roberts Research Institute, London, Ontario, Canada.
Eur J Immunol. 1995 Jul;25(7):1999-2004. doi: 10.1002/eji.1830250730.
When the CD28 membrane glycoprotein of T cells binds to its ligand, a signal is transmitted that is required for T cell receptor-induced proliferation and cytokine secretion: T cells are not stimulated by the CD28 signal alone. Ligation of CD28 initiated sphingomyelin hydrolysis and generated ceramide. Treatment of T cells with either exogenous sphingomyelinase or a cell-permeable ceramide analogue. C6-ceramide, mimicked the CD28 signal by inducing T cell proliferation and interleukin-2 gene transcription. Stabilization of interleukin-2 mRNA was also observed in C6-ceramide-treated cells. Thus, the sphingomyelin-ceramide pathway is a candidate for mediating the costimulatory signal.
当T细胞的CD28膜糖蛋白与其配体结合时，会传递一种信号，该信号是T细胞受体诱导的增殖和细胞因子分泌所必需的：T细胞不会仅被CD28信号刺激。CD28的连接引发了鞘磷脂水解并生成了神经酰胺。用外源性鞘磷脂酶或细胞可渗透的神经酰胺类似物C6-神经酰胺处理T细胞，通过诱导T细胞增殖和白细胞介素-2基因转录模拟了CD28信号。在C6-神经酰胺处理的细胞中也观察到白细胞介素-2 mRNA的稳定性。因此，鞘磷脂-神经酰胺途径是介导共刺激信号的一个候选途径。
