Latifa Bousarghin
Univ Rennes, INRAE, Rennes,France
Title: A new multicellular model including enteroendocrine cells to characterize interactions between gut microbiota and host cells
Biography
Biography: Latifa Bousarghin
Abstract
A number of factors can disturb or alter the gut microbiota resulting in dysbiosis. However, the mechanism by which gut bacteria interact with the host leading to disease are still unclear. For a better understanding, an in vitro model including the diversity of cell types present in intestinal epithelium is needed.
In the present study, we have generated a new in vitro model of intestinal epithelium recapitulating the four main intestinal cell types (enterocytes, goblet cells, M cells, and enteroendocrine cells). This multicellular model was stimulated by commensal (R. intestinalis and Bacteroides) and pathogenic bacteria (Salmonella).
Methods: Cultures of R. intestinalis, B. fragilis, or S. Heidelberg in complete DMEM were added to apical side of the multicellular model during 3h. For R. intestinalis, we also investigated if their cell-free supernatants could have an impact on host cells.
Findings : We have shown that in the presence of bacteria, the expression of IL-8 was more important for S. Heidelberg than R. intestinalis or B. fragilis . It is well known that Salmonella activated IL-8 by its flagellin recognition by TLR5. For endocrine function, we have also a difference between the three bacteria. Only B. fragilis showed a significant increase of GCG expression compared to S. Heidelberg and R. As R. intestinalis and B. fragilis had beneficial effect, we have tested their cell-free supernatant on the quadricellular model. We have evaluated the impact of these supernatant on the integrity of the epithelium. in the presence of R. intestinalis, TEER (intestinal barrier integrity) increased by two-fold after an incubation of 13h. We can speculate when Roseburia and Bacteroides are decreased, their beneficial effect are also decrease