Initial events in the breakthrough of the epithelial barrier of the small intestine by Angiostrongylus cantonensis
AbstractAlthough the third-stage larvae of Angiostrongylus cantonensis (AcL3) are thought to initiate infection by penetrating the epithelium of the small intestine, the mode of intestinal invasion remains obscure. Considering the inaccessibility of the gut tract and the need to sacrifice animals for this type of study, we devised an in vitro cell-parasite co-culture system to examine the initial cellular and molecular events between AcL3 and host epithelia. No apoptosis augmentation was detected in enterocytes after introduction of larvae. A significant increase in dead cells was detected in IEC-6, NCM460 and 293T after incubating for 4 h, with AcL3 wounding rat small intestinal epithelial cells IEC-6 more rapidly. Under a scanning electron microscope (SEM), cell gap opening was visualized in the IEC-6 monolayer treated with AcL3. Loosening of the extracellular matrix (ECM) of the monolayer was found to be involved in the parasite-cell interactions. Pretreating the AcL3 with a protease inhibitor attenuated its penetration ability of the artificial intestine barrier. In conclusion, AcL3 broke through the intestinal barrier of the host with the assistance of mechanical injury and the opening of a cell gap, but without causing apoptosis. The interaction platform presented here may provide direct insight into the cellular and molecular events during worm invasion of host enterocytes.
How to Cite
Authors grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution 4.0 International License that allows others to share the work with an acknowledgment of the work’s authorship and initial publication in this journal.