Investigating the effects of outer membrane vesicles derived from Campylobacter jejuni on the survival of HT-29 epithelial cells in vitro

Background: Campylobacter jejuni is an important pathogenic bacterium that is associated with diarrhea and gastroenteritis in several animal species and humans. The secretion of virulence factors is a crucial strategy that enteric bacterial pathogens use to interact with host cells, promote their survival, and damage the host. Many bacterial pathogens utilize outer membrane vesicles (OMVs) to deliver virulence factors into host cells. C. jejuni can produce nanosized OMV cargos, which have been proposed to have a key role in disease progression, pathogenesis, and immune system modulation. This study aimed to assess the effect of OMVs derived from C. jejuni on the survival of HT-29 intestinal cells in vitro. Materials and Methods: In this work, C. jejuni clinical strain RIGLD 4-151 was used. C. jejuni OMVs were isolated using ultracentrifugation and were analyzed by scanning electron microscopy (SEM) and dynamic light scattering (DLS). HT-29 human colon cancer epithelial cells were treated with OMVs for 24, 48, and 72 hours. Cell viability of HT-29 cells exposed to OMVs was measured by MTT assay. Results: Our results showed that C. jejuni strain RIGLD 4-151 released round-shaped nanovesicles ranging from 10 to 250 nm. The cytotoxicity assays unveiled a dose-dependent reduction in cell viability following exposure to various concentrations of C. jejuni OMVs. Conclusion: The present study demonstrated that OMVs derived from C. jejuni strain RIGLD 4-151 can significantly affect viability of HT-29 cells. Further research is required to elucidate the definite role of OMVs derived from C. jejuni strain RIGLD 4-151 in the pathogenesis of C. jejuni.