Zn2+ 螯合剂DTPA（二乙基三胺五乙酸）对人工关节假体感染后表皮 葡萄球菌生物膜形成及相关基因表达的影响

目的:探讨DTPA对人工关节假体(prosthetic joints infection,PJI)感染后表皮葡萄球菌生物膜形成及所需基因聚集相关蛋白(AAP)基因表达的影响。方法:构建新西兰大白兔假体感染表皮葡萄球菌生物膜模型,随机分为实验组(n=25)和对照组(n=25),对照组只注射细菌,实验组在注入细菌的同时,注射DTPA,分别于注射后第2、4、6、8、16天灌洗、收集膝关节液,采用RT-PCR方法检测不同时间点目的基因AAP基因表达的变化。对不同时间点的假体感染动物行膝关节假体扫描电镜和假体周围组织学观察。结果:DTPA可以显著抑制AAP基因的表达,扫描电镜观察第2、4、6、8、16天实验组较对照组假体表面粘附表皮葡萄球菌明显减少(P<0.05),生物膜明显受抑制。实验组假体周围组织炎性反应较对照组明显减轻。结论:DTPA可以抑制表皮葡萄球菌生物膜形成中相关蛋白AAP基因的表达,可能抑制生物膜的形成。

DTPA Inhibits Formation of Staphylococcus Epidermidis Biofilm Associated with Prosthetic Joints: Relative Gene (AAP) Expressions

Objective: To investigate the inhibitory effect of DTPA on the formation of Staphylococcus epidermidis biofilm and the expressions of relative genes(AAP).Methods: New Zealand white rabbits were used to establish the animal model of prosthetic joints infection.Rabbits were randomly divided into the experimental group and control group.The bacteria were injected with 0.1ml 1%DTPA into the knee of rabbits in experimental group;The rabbits were injected with bacteria in the control group.Synovial fluid was extracted in the 2,4,6,8 and 16 days.The expressions of AAP were detected by the way of fluorescent quantitation RT-PCR.Scanning electron mi-croscopy and histological observations were detected.Results: DTPA can significantly inhibit the expression of AAP in Staphylococcus epidermidis.Scanning electron microscopy found on the day of 2,4,6,8,16 the number of bacteria adhere to the prosthetic surface had decreased significantly in experimental group compared with that in the control group.Conclusion: DTPA can inhibit the formation of the biofilm of Staphylococcus epidermidisthrough suppressing the relative genes.