嗜水气单胞菌HEC毒素对鲤内皮细胞的毒性

Toxic effects of HEC toxin from Aeromonas hydrophila on endothelial cells of Cypripus carpio

体外培养鲤血管内皮细胞 (EC) ,取 10 0 0 0ml嗜水气单胞菌悬液 ,盐析和层析后获得HEC毒素 (外毒素 ) ,测定分析不同质量浓度HEC毒素 (10 2 4 .0 0 ,2 5 6 .0 0 ,6 4 .0 0 ,16 .0 0 ,4 .0 0 ,1.0 0 ,0 .2 5 μg/ml)对鲤EC的半感染浓度(TCID50 )及观察在工作浓度 (16TCID50 )下内皮细胞的损伤和亚显微变化。结果表明 :1)HEC毒素对鲤科鱼类的红细胞有很强的破坏性 (溶血价 >8× 10 3 HU/mg) ;2 )对鲤EC的TCID50 为 5 .85 μg/ml;3)在 16TCID50 HEC毒素诱导下 ,6h的EC单层出现空斑 ,12h的EC有部分脱落 ,2 4h的EC全部脱落 ;超薄切片中 12h的EC微绒毛有部分丢失 ,细胞器和核质严重病变 ,细胞膜完整性被破坏 ,2 4h的EC核肿胀 ,微绒毛。

HEC toxin was separated from Aeromonas hydrophila Ah J 1 strain by ammonium sulfate pricipitation DEAE cellulose chromatography and sephadex G 100 gel filtration,and its 50% tissue culture infective dose (TCID 50 ) was detected by analyzing different concentrations of HEC toxin . The HEC toxin concentrations were prepared at 1 024.00,256.00,64.00,16.00,4.00,1.00 and 0.25 μg/ml. Using reverse microscope and electron microscope, the changes of the endothelial cells (EC) with HEC toxin concentrations at 16 TCID 50 were observed. The results show that : 1)the erythrocytes of cypinidae is destroyed strongly by HEC toxin ,and its hemolytic titer is more than 8×10 3 HU/mg; 2)the TCID 50 for common carp EC is 5.85 μg/ml ;3) under the stress of HEC (16 TCID 50 ) ,the plague appears in EC monolayer in 6 h,and EC begin to suspend in 12 h and all EC suspend in 24 h. Under the electron microscope ,the EC has some changes that ①some microvillis lost,and abnormal organelles , euchromatins and swollen nuclears are obvious in 12 h ; ② swollen nucleus is found ,and all the microvillis, organelles and euchromatins lost in 24 h.