抗菌膜单克隆抗体对志贺菌入侵HeLa细胞的影响

采用HeLa细胞入侵及其阻断试验 ,观察抗志贺菌菌膜蛋白和LPS的单抗对志贺菌入侵HeLa细胞的影响。并用免疫印迹法初步分析了感染细胞及其培养上清中的蛋白成分。结果抗菌膜蛋白的单抗 2 6C3不但没有阻断反而促进了细菌的入侵 ,在HeLa细胞胞浆内出现成堆的F2a菌 ,其绝对菌数远远超过未经该单抗处理的F2a菌感染的HeLa细胞组。免疫印迹显示单抗处理组细胞培养液中IpaB、IpaC蛋白明显比未经单抗处理组多。抗LPS的单抗对细菌入侵具有一定的阻断作用。提示抗菌膜蛋白单抗所识别的IpaB表位 ,具有调节F2a菌进入HeLa细胞的能力。其作用机制可能是通过细菌分泌器 ,使分泌IpaB、IpaC蛋白增多。

Influence of Monoclonal Antibody Against Membrane Component on the Invasion of HeLa Cells by Shigella

The influence of monoclonal antibody against membrane components on the invasion of HeLa cells by Shigella was observed by blocking test,and the proteins in the supernatants of cell cultures and in the cytoplasm of infected HeLa cells were analyzed by Western blotting technique. Experimental results showed that McAb26C3 did not block the invasion of Shigella into HeLa cells with an increasing number of Shigella F2a in the cells. By immunoblotting analysis,it was found that the contents of IpaB and IpaC proteins in the supernatant of cell cultures of the treated group with McAb were apparently higher than those of the controls. It concludes that the epitope of IpaB identified by the McAb against the protein component of Shigella expresses its regulatory effect on the invasion process,and its mechanism of action might be due to an increasing secretion of IpaB and IpaC proteins.