血小板抗表皮葡萄球菌生长的研究

Antibacterial Effect of Platelets on Staphylococcus Epidermidis

目的：探讨血小板对表皮葡萄球菌（staphylococcus epidermidis ，SE）的抗菌效果及相关机制。方法体外建立105 CFU／ml表皮葡萄球菌接种浓度的BHI培养体系，分别加入终浓度为400×10^9／L血小板（PLT组）、血浆（阳性对照组）与BHI培养基（阴性对照组）共培养12 h以后，观察比较各组菌液的浑浊程度，并采用倍比稀释、涂布计数法检测血小板体外抗菌的效果，同时绘制血小板抗菌曲线。通过透射电镜观察细菌亚显微结构的完整性，并初步探究血小板的抗菌机制。结果血小板对表皮葡萄球菌有明显的抑制作用，且其抑制效果虽较血浆组出现的晚，但持续时间更久；透射电镜结果显示血小板抗菌组表皮葡萄球菌染色质结构异常、发生凝集并有部分断裂，且处于分裂期的细菌比例明显降低。结论血小板可能通过破坏表皮葡萄球菌染色质的结构，进而影响细菌的分裂，发挥抗菌作用。

Objective To explore the antibacterial effect and mechanisms of platelets （PLT）on Staphylococcus epidermidis （SE）.Methods Built infectious model of SE in vitro,whose final concentration was 105 CFU/ml in the reaction.Separately cocultured these models with PLT （the final concentration 400 × 10^9/L）-plasma （positive control）and BHI medium 12 hours later,and detected the antibacterial effect of PLT by making a liquid thinner and spreading counting method,and draw-ing antibacterial curve.Meanwhile,observed the bacterial structure by transmission electron microscope （TEM）,and initially explored the antibacterial mechanism of PLT.Results The study showed the antibacterial effect of PLT on SE was very ob-vious,which appeared later than the plasma （M）group,but enduring.The images of TEM showed an electronlight region appeared in the centre of bacterium,contained condensed DNA molecules and leaded to slower fission.Conclusion PLT can damage the DNA structure of SE,and then affect the fission of SE,finally inhibit the proliferation of SE.