Deciphering Distinct Pathogenetic Strategies Employed by Shigella Serotypes Using Human Intestinal Organoids

We aimed to develop an experimental model system using human intestinal organoids to examine the invasion abilities of different Shigella species ((S. dysenteriae, S. flexneri, and S. sonnei). Human intestinal organoids (enteroids) were developed and established using human intestinal biopsies. Three distinct species of Shigella were used to infect enteroids. The ability to invade was checked by gentamicin protection assay. We visualized the entry of Shigella and morphological changes induced by bright field microscopy and immunofluorescence microscopy. We studied the differential expression of the ipaH gene in infected human intestinal organoids and correlated it with the degree of invasiveness. Our results demonstrated that different species of Shigella vary in their invasive ability, with S.dysenteriae being more invasive than S.flexneri and S.sonnei. Our data showed that the intestinal organoid model is feasible for studying Shigella pathogenesis. This model would be suitable for discovering new antigens and testing vaccines against Shigella. This investigation holds significant promise for improving our understanding of Shigella pathogenesis. Furthermore, human intestinal organoids provide a rapidly replicable model system model system of Shigella pathogenesis due to their ability to be expanded, genetically modified and cryogenically maintained. Insights gained from this study could have broader implications for addressing diarrheal illnesses, particularly in regions where Shigella infections pose a significant public health burden. To our knowledge, this is the first study from India to utilize human-derived intestinal organoids to systematically evaluate the differential invasion capacity, epithelial damage, and virulence gene expression induced by clinically prevalent Shigella serotypes.