Mangeney M, Lingwood C A, Taga S, Caillou B, Tursz T, Wiels J
Laboratoire de Biologie des Tumeurs Humaines, CNRS URA 1156, Villejuif, France.
Cancer Res. 1993 Nov 1;53(21):5314-9.
Gb3/CD77 is a glycolipid antigen, specifically expressed on two different B-cell populations, Burkitt's lymphoma and a subset of tonsillar B-lymphocytes located in germinal centers, which could be the normal counterpart of Burkitt cells. Both Gb3/CD77(+) populations have recently been shown to enter programmed cell death (apoptosis) readily. Here we show that verotoxin, also called Shiga-like toxin, which is known to bind to the carbohydrate moiety of Gb3/CD77, induces cell death in Gb3/CD77(+) Burkitt's lymphoma cells, not only by inhibiting protein synthesis as classically described but also through an additional mechanism, namely apoptosis. Furthermore a recombinant B-subunit of verotoxin, which carries only the binding property of the holotoxin, also induces apoptosis in Gb3/CD77(+) cells. Gb3/CD77 could thus represent the first example of a glycolipid antigen able to transduce a signal leading to apoptosis.
Gb3/CD77是一种糖脂抗原，在两种不同的B细胞群体上特异性表达，即伯基特淋巴瘤细胞以及位于生发中心的扁桃体B淋巴细胞亚群，后者可能是伯基特细胞的正常对应物。最近发现，这两种Gb3/CD77阳性群体都容易进入程序性细胞死亡（凋亡）过程。在此我们表明，志贺样毒素（也称为维罗毒素）已知可与Gb3/CD77的碳水化合物部分结合，它不仅通过经典描述的抑制蛋白质合成，还通过另一种机制，即凋亡，诱导Gb3/CD77阳性的伯基特淋巴瘤细胞死亡。此外，仅具有全毒素结合特性的重组维罗毒素B亚基也能诱导Gb3/CD77阳性细胞凋亡。因此，Gb3/CD77可能代表了一种能够转导导致凋亡信号的糖脂抗原的首个实例。
