Effects of exosomes derived from Trichinella spiralis infective larvae on intestinal epithelial barrier function

Muscle larvae of Trichinella spiralis parasitize the host intestinal epithelium. The mechanisms of exosomes participating in the invasion of T. spiralis muscle larvae are unclear. Hence, the purpose of this study was to explore the effect of exosomes derived from T. spiralis infective larvae ( Ts Exos) on the barrier function of porcine small intestinal epithelial cells (IPEC-J2). First, Ts Exos were successfully obtained, and their ingestion by epithelial cells was validated. Furthermore, the optimal induction condition was determined by the CCK8 kit, and we found that exposure to 150 μg/mL Ts Exos for 12/24 h decreased the viability of IPEC-J2 cells by 30%. Based on this outcome, the effects of Ts Exos on cell biological processes and tight junctions were studied. After coincubation of Ts Exos and IPEC-J2 cells, the results showed a significant increase in the content of FITC-dextran and in the levels of lactate dehydrogenase (LDH) and reactive oxygen species (ROS). The rate of apoptosis increased by 12.57%, and nuclear pyknosis and nuclear rupture were observed. After the cells were induced by Ts Exos, the expression of IL-1 was upregulated, but the expression of IL-10, TGF-β, TLR-5, MUC-1 and MUC-2 was downregulated. Ts Exo induction also led to a decrease in the levels of ZO-1, CLDN-3, and OCLN. In conclusion, Ts Exos are involved in several cellular biological processes, and they function by disrupting physiological and biochemical processes, hyperactivating innate immunity, and damaging tight junctions.