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Human Intestinal Enteroids as a Model System of Shigella Pathogenesis.

ABSTRACT: The enteric bacterium and intracellular human pathogen Shigella causes hundreds of millions of cases of the diarrheal disease shigellosis per year worldwide. Shigella is acquired by ingestion of contaminated food or water; upon reaching the colon, the bacteria invade colonic epithelial cells, replicate intracellularly, spread to adjacent cells, and provoke an intense inflammatory response. There is no animal model that faithfully recapitulates human disease; thus, cultured cells have been used to model Shigella pathogenesis. However, the use of transformed cells in culture does not provide the same environment to the bacteria as the normal human intestinal epithelium. Recent advances in tissue culture now enable the cultivation of human intestinal enteroids (HIEs), which are derived from human intestinal stem cells, grown ex vivo, and then differentiated into "mini-intestines." Here, we demonstrate that HIEs can be used to model Shigella pathogenesis. We show that Shigella flexneri invades polarized HIE monolayers preferentially via the basolateral surface. After S. flexneri invades HIE monolayers, S. flexneri replicates within HIE cells and forms actin tails. S. flexneri also increases the expression of HIE proinflammatory signals and the amino acid transporter SLC7A5. Finally, we demonstrate that disruption of HIE tight junctions enables S. flexneri invasion via the apical surface.

SUBMITTER: Koestler BJ

PROVIDER: S-EPMC6434139 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Human Intestinal Enteroids as a Model System of Shigella Pathogenesis.

Koestler Benjamin J BJ Ward Cara M CM Fisher C R CR Rajan Anubama A Maresso Anthony W AW Payne Shelley M SM

Infection and immunity 20190325 4

The enteric bacterium and intracellular human pathogen Shigella causes hundreds of millions of cases of the diarrheal disease shigellosis per year worldwide. Shigella is acquired by ingestion of contaminated food or water; upon reaching the colon, the bacteria invade colonic epithelial cells, replicate intracellularly, spread to adjacent cells, and provoke an intense inflammatory response. There is no animal model that faithfully recapitulates human disease; thus, cultured cells ha ...[more]

PMID: 30642906

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Project description:UnlabelledHuman gastrointestinal tract research is limited by the paucity of in vitro intestinal cell models that recapitulate the cellular diversity and complex functions of human physiology and disease pathology. Human intestinal enteroid (HIE) cultures contain multiple intestinal epithelial cell types that comprise the intestinal epithelium (enterocytes and goblet, enteroendocrine, and Paneth cells) and are physiologically active based on responses to agonists. We evaluated these nontransformed, three-dimensional HIE cultures as models for pathogenic infections in the small intestine by examining whether HIEs from different regions of the small intestine from different patients are susceptible to human rotavirus (HRV) infection. Little is known about HRVs, as they generally replicate poorly in transformed cell lines, and host range restriction prevents their replication in many animal models, whereas many animal rotaviruses (ARVs) exhibit a broader host range and replicate in mice. Using HRVs, including the Rotarix RV1 vaccine strain, and ARVs, we evaluated host susceptibility, virus production, and cellular responses of HIEs. HRVs infect at higher rates and grow to higher titers than do ARVs. HRVs infect differentiated enterocytes and enteroendocrine cells, and viroplasms and lipid droplets are induced. Heterogeneity in replication was seen in HIEs from different patients. HRV infection and RV enterotoxin treatment of HIEs caused physiological lumenal expansion detected by time-lapse microscopy, recapitulating one of the hallmarks of rotavirus-induced diarrhea. These results demonstrate that HIEs are a novel pathophysiological model that will allow the study of HRV biology, including host restriction, cell type restriction, and virus-induced fluid secretion.ImportanceOur research establishes HIEs as nontransformed cell culture models to understand human intestinal physiology and pathophysiology and the epithelial response, including host restriction of gastrointestinal infections such as HRV infection. HRVs remain a major worldwide cause of diarrhea-associated morbidity and mortality in children ?5 years of age. Current in vitro models of rotavirus infection rely primarily on the use of animal rotaviruses because HRV growth is limited in most transformed cell lines and animal models. We demonstrate that HIEs are novel, cellularly diverse, and physiologically relevant epithelial cell cultures that recapitulate in vivo properties of HRV infection. HIEs will allow the study of HRV biology, including human host-pathogen and live, attenuated vaccine interactions; host and cell type restriction; virus-induced fluid secretion; cell-cell communication within the epithelium; and the epithelial response to infection in cultures from genetically diverse individuals. Finally, drug therapies to prevent/treat diarrheal disease can be tested in these physiologically active cultures.

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Dataset Information

Human Intestinal Enteroids as a Model System of Shigella Pathogenesis.

Publications

Human Intestinal Enteroids as a Model System of <i>Shigella</i> Pathogenesis.

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