The role of multimerin1 and VacA, an exotoxin released by H. pylori on ITP.

人类和小鼠的血小板在幽门螺杆菌感染下被激活。在这种情况下，我们研究了幽门螺杆菌释放的外毒素VacA的作用。酸激活的VacA，而不是加热的VacA，诱导血小板CD62P的表达。然而，VacA不与血小板膜上存在的所谓VacA受体发生反应。因此，我们使用MALDI-TOF-MS分析了通过VacA亲和层析获得的VacA相关蛋白。在两个连续的实验中检测到作为VacA结合蛋白的Multimerin1。等离子体共振证实了它们的结合，点阵分析显示，多聚蛋白1的肽序列AA 321-340是VacA的结合位点。总之，我们提出了一种新的multimerin1和VacA之间的相互作用，这可能为幽门螺杆菌感染下幽门螺杆菌诱导的血小板活化提供了另一种见解。

Platelets were activated under the infection with H. pylori in human and mice. We investigated the role of VacA, an exotoxin released by H. pylori in this context. Acid-activated VacA, but not heated VacA, induced platelet CD62P expression. However, VacA reacted with none of the alleged VacA receptors present on platelet membranes. We therefore analyzed VacA associated proteins obtained through VacA affinity chromatography, using MALDI-TOF-MS. Multimerin1 was detected in two consecutive experiments, as the binding protein for VacA. Plasmon resonance confirmed their binding, and dot print analysis revealed that the peptide sequence AA 321-340 of multimerin 1 is the binding site for VacA. In conclusion, we propose a new interaction between multimerin1 and VacA , which may give another insight into H. pylori-induced platelet activations under H. pylori infection.