猪链球菌溶血素(SLY)引起血小板聚集活性分析

Activity identification of Streptococcus suis suilysin inducing platelets aggregation

目的研究重组表达的2型猪链球菌溶血素(SLY)与血小板的相互作用,为临床猪链球菌感染的救治提供理论基础。方法镍柱亲和层析法纯化重组SLY蛋白,光密度法检测其溶血活性,再通过血小板聚集仪和扫描电子显微镜观察SLY蛋白与血小板的相互作用,并研究抗血小板药物阿司匹林对SLY引起的血小板聚集的影响,通过比较野生株05ZYH33和sly基因突变株Δsly对小鼠体内血小板体积和数量的影响,推测SLY蛋白对体内血小板的影响。结果与结论重组SLY蛋白溶血活性为2000 HU,1μg/ml SLY蛋白可引起血小板高度聚集,5 mmol/L阿司匹林可显著抑制聚集,SLY蛋白可引起小鼠体内单个血小板体积增大和血小板数量减少。

Objective To explore the interaction of streptococcus suis serotype 2 recombinant suilysin（ SLY） with platelets,and provide the theoretical basis for clinic treatment of patients infected with S. suis. Methods The nickel column affinity chromatography was used to purify the recombinant SLY. The hemolytic acivity was identified by optical density before the platelets aggregation induced by a SLY was detected by a platelet aggregometer or electron microscope and the effect of aspirin on platelets aggregation was analyzed. The impact of wild type 05ZYH33 and sly-deficient mutant strain ΔSLY on platelets of mice was compared to predict the interaction of the SLY with platelets in vivo. Results and Conclusion Hemolytic activity of recombinant SLY was 2000 hemolytic units（ HU） and platelets aggregation was induced at 1 μg / ml. The aggregation can be inhibited by aspirin in 5 mmol / L. SLY can also increase the volume and reduce the amount of platelets in mice.