猪链球菌2型溶菌酶释放蛋白引起血小板聚集的机制研究

Mechanism of platelet aggregation induced by Streptococcus suis serotype 2 muramidase-released pro tein （MRP）

目的研究猪链球菌2型溶菌酶释放蛋白（MRP）引起血小板聚集的作用机制，为猪链球菌临床救治提供科学依据与理论基础。方法镍柱亲和层析法纯化MRP-N、MRP-C蛋白，通过血小板聚集仪、血栓弹力图仪以及扫描电子显微镜观察MRP蛋白引起血小板聚集的情况。结果猪链球菌2型野生株可以引起血小板的聚集，而突变株ΔMRP则不能；MRP-N蛋白可以引起血小板的聚集，而MRP-C蛋白则不能；β2整合素受体抑制剂（GPRP）能显著抑制MRP引起的血小板聚集。结论MRP是猪链球菌2型引起血小板聚集的关键因子，MRP通过β2整合素受体途径引起血小板的聚集。

ObjectiveTo study the mechanism of platelet aggregation induced by Streptococcus suis serotype 2 muramidase-released protein （MRP） and to provide scientific proof and theoretical basis for clinical treatment of patients with Streptococcus suis infection. MethodsNickel column affinity chromatography was used to purify recombinant proteins of MRP-N and MRP-C. Platelet aggregometer, thromboelastography （TEG） and scanning electron microscope were used to observe the platelet aggregation induced by MRP. ResultsStreptococcus suis 2 wild type strain, but not the mutant strain ΔMRP, could induce platelet aggregation. It was MRP-N but not MRP-C that induced platelet aggregation. GPRP, an inhibitor of β2 integrin receptor, could significantly inhibit the platelet aggregation induced by MRP. ConclusionStreptococcus suis 2 MRP induces platelet aggregation through β2 integrin receptor pathway.