中文摘要：

目的研究铜绿假单胞菌分泌物对中性粒细胞趋化功能的影响。方法用percoll密度梯度离心法分离小鼠骨髓中性粒细胞并用FACS检测其纯度;铜绿假单胞菌PAO1静置培养5 d后涡旋并离心收集其上清;通过TAXIScan-FL检测被膜上清PAO1 d5（PAO1菌株静置培养第5天）的趋化作用;不同浓度的f MLP所引起的中性粒细胞趋化运动及PAO1 d5上清稀释50倍后的趋化作用;PAO1 d5上清对fMLP所引起的中性粒细胞趋化运动的影响。结果分离的小鼠骨髓中性粒细胞纯度大于90%;TAXIScan-FL检测被膜上清有趋化作用,但是速度及方向上与f MLP及LTB4有明显差别（P〈0.001）;高浓度的f MLP对中性粒细胞的趋化作用减弱,PAO1 d5稀释50倍后趋化作用消失;PAO1 d5上清可以抑制f MLP所引起的中性粒细胞趋化运动。结论 PAO1d5被膜上清中存在抑制中性粒细胞趋化的物质。

英文摘要：

This study designed to explore the effect of Pseudomonas aeruginosa secretions on neutrophilchemotactic migration.Bone marrow neutrophils were separated from mice by percoll density gradientcentrifugation and their purity was tested by FACS;after 5 days of static culture,P.aeruginosa PAO1 was eddiedand centrifuged to collect the supernatant;TAXIScan-FL chemotaxis device was applied to detect the chemotacticactivity of PAO1 d5（the strain of PAO1 after static culture for 5 days） supernatant,f MLP and PAO1 d5 supernatantdiluted 50 times;the effect of PAO1 d5 supernatant on f MLP-induced neutrophil chemotaxis was evaluated.Datashowed that the purity of isolated mouse bone marrow neutrophils exceeded 90%;the supernatant of PAO1 d5 had chemotactic activity,but cells stimulated with PAO1 supernatant had lower velocity and directionalitycompared to f MLP or LTB4 stimulated cells.At the high concentrations of f MLP,neutrophil chemotaxis wasreduced.The inhibitory effect elicited by PAO1 supernatant was not caused by high f MLP level in the supernatant.Taken together,the supernatant of PAO1 d5 contain inhibitor of neutrophils chemotaxis.