【摘要】 目的探讨铜绿假单胞菌外毒素A(PEA)对人淋巴细胞转化的抑制作用及抗-PEA血清的中和作用。方法采集健康成年人的静脉血,密度梯度离心分离外周血单个核细胞(PBMC)。采用台盼蓝染色排除法及四甲基偶氮唑蓝(MTT)法确定PEA对淋巴细胞的非毒性剂量范围。抑制实验分为对照组、4个不同浓度PEA组及抗血清预处理组6个组。非毒性剂量范围内不同浓度的PEA、植物血凝素(PHA)与淋巴细胞37°C、5%CO2共同温育48 h,MTT法测定淋巴细胞转化。结果PEA对淋巴细胞的非毒性剂量范围为0~800 ng/m l。PEA浓度在50~400 ng/m l,对淋巴细胞转化存在显著抑制作用(P<0.05);而抗-PEA血清可完全中和PEA对淋巴细胞转化的抑制作用,与对照组比较差异无显著性(P>0.05)。结论非毒性剂量的PEA对淋巴细胞转化存在抑制作用,抗-PEA血清具有保护性中和作用。更多还原

【Abstract】 Objective To explore the inhibition of Pseudomonas aeruginosa exotoxin A（PEA） on lymphoproliferation and neutralization of anti-PEA serum. Methods Lymphocytes were prepared from blood of healthy adults by density gradient centrifugation.Trypan blue dye exclusion method and MTT assay were used to determine the uncytoxic dose ranges of PEA.Samples were divided into six groups including control group,four groups with different PEA concentration and anti-PEA serum pretreated group.PEA within uncytoxic dose ranges,lymphocyte and phytohemagglutin（PHA） were incubated at 37（°C） in the presence of 5% CO₂ for 48 h.Lymphoproliferation was measured by MTT assay. Results Uncytoxic dose ranges of PEA on lymphocyte were 0-800 ng/ml.PEA（50-400 ng/ml） inhibited significantly lymphoproliferation（P<（0.05））;Anti-PEA serum neutralized completely the inhibiting effect of PEA.There was no significant difference between anti-PEA serum pretreated group and the control group（P>（0.05））. Conclusions Uncytoxic dose PEA can inhibit lymphoproliferation and anti-PEA serum can neutralize the inhibition of PEA.更多还原