Scheuplein Felix, Adriouch Sahahil, Glowacki Gustavo, Haag Friedrich, Seman Michel, Koch-Nolte Friedrich
Institute of Immunology, University Hospital, D-20246 Hamburg, Germany.
Ann N Y Acad Sci. 2003 Dec;1010:296-9. doi: 10.1196/annals.1299.051.
Cytotoxicity induced by protein ADP-ribosylation is a common theme of certain bacterial toxins and of the mammalian ectoenzyme ART2. Exposure of T cells to NAD, the substrate for ART2-catalyzed ADP-ribosylation, induces exposure of phosphatidylserine, uptake of propidium iodide, and fragmentation of DNA. ART2-specific antibodies raised by gene gun immunization block NAD-induced apoptosis. ART2 catalyzed ADP-ribosylation of cell membrane proteins induces formation of cytolytic membrane pores by activating the P2X7 purinoceptor. This alternative pathway to T cell apoptosis could be triggered upon the release of NAD from intracellular stores, for example, during inflammatory tissue damage.
蛋白质 ADP 核糖基化诱导的细胞毒性是某些细菌毒素和哺乳动物胞外酶 ART2 的共同特征。T 细胞暴露于 ART2 催化的 ADP 核糖基化底物 NAD 会导致磷脂酰丝氨酸暴露、碘化丙啶摄取和 DNA 片段化。通过基因枪免疫产生的 ART2 特异性抗体可阻断 NAD 诱导的细胞凋亡。ART2 催化细胞膜蛋白的 ADP 核糖基化通过激活 P2X7 嘌呤受体诱导溶细胞性膜孔的形成。例如，在炎症组织损伤期间，细胞内储存的 NAD 释放时，可能会触发这条 T 细胞凋亡的替代途径。
