免疫血清对旋毛虫感染性幼虫侵入肠上皮细胞及其发育的影响

Objective To observe the effect of sera from mice immunized with excretory-secretory (ES) antigens or surface antigens of T. spiralis larvae on the invasion of intestinal epithelial cells in vitro by the larvae and their development. Methods HCT-8 cells grown to confluence were overlaid with the larvae suspended in semisolid medium (RPMI-1640 medium +1.75% agarose)，and then the larvae were observed by using an inverted microscope after Cultures were incubated at 37 C under 5% CO2 for 12、24、36、72、96 h; The larval development and its invasion of intestinal epithelial cells were observed under inverted microscope after 15 min when HCT-8 cells were overlaid with the larvae suspended in semisolid medium supplemented with immune sera. Finally，the L1 and L2-L4 larvae were observed and enumerated by indirect fluorescent antibody test (IFAT) after being incubated for 36 h. Results When the larvae were cultured in semisolid medium，the larvae could invade the HCT-8 cell monolayer. The larvae could shed 1～2 times at 36 h to 72 h of culture and early adult was observed at 96h of culture. Cephalic caps on larvae cultured with medium containing sera of mice immunized with ES antigens or infected by T. spiralis were found at 15 min of culture，but the caps were not observed on larvae cultured in medium containing sera of normal mice or without sera，and the larvae with cephalic caps did not invade the cell monolayer. When the larvae cultured for 36 h with medium containing sera of mice immunized with ES antigens or surface antigens of T. spiralis larvae，the percentages of L2-L4 larvae (2.25%，2.20%) were significantly lower than that cultured in medium containing normal mouse sera （24.74%）( P<0.05). Conclusion The sera from mice immunized with excretory-secretory (ES) antigens of T. spiralis larvae prevent the invasion of intestinal epithelial cells in vitro by the larvae，both the immune sera from mice immunized with ES and surface antigens prevent the development (ecdysis) of some larvae.