title: Intestinal Enteroids Model Guanylate Cyclase C-Dependent Secretion Induced by Heat-Stable Enterotoxins.
abstract: Enterotoxigenic Escherichia coli (ETEC) causes ∼20% of the acute infectious diarrhea (AID) episodes worldwide, often by producing heat-stable enterotoxins (STs), which are peptides structurally homologous to paracrine hormones of the intestinal guanylate cyclase C (GUCY2C) receptor. While molecular mechanisms mediating ST-induced intestinal secretion have been defined, advancements in therapeutics have been hampered for decades by the paucity of disease models that integrate molecular and functional endpoints amenable to high-throughput screening. Here, we reveal that mouse and human intestinal enteroids in three-dimensional ex vivo cultures express the components of the GUCY2C secretory signaling axis. ST and its structural analog, linaclotide, an FDA-approved oral secretagog, induced fluid accumulation quantified simultaneously in scores of enteroid lumens, recapitulating ETEC-induced intestinal secretion. Enteroid secretion depended on canonical molecular signaling events responsible for ETEC-induced diarrhea, including cyclic GMP (cGMP) produced by GUCY2C, activation of cGMP-dependent protein kinase (PKG), and opening of the cystic fibrosis transmembrane conductance regulator (CFTR). Importantly, pharmacological inhibition of CFTR abrogated enteroid fluid secretion, providing proof of concept for the utility of this model to screen antidiarrheal agents. Intestinal enteroids offer a unique model, integrating the GUCY2C signaling axis and luminal fluid secretion, to explore the pathophysiology of, and develop platforms for, high-throughput drug screening to identify novel compounds to prevent and treat ETEC diarrheal disease.
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Amanda M
authors.initials: AM
authors.lastname: Pattison
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Erik S
authors.initials: ES
authors.lastname: Blomain
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Dante J
authors.initials: DJ
authors.lastname: Merlino
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Fang
authors.initials: F
authors.lastname: Wang
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: Mary Ann S
authors.initials: MA
authors.lastname: Crissey
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Crystal L
authors.initials: CL
authors.lastname: Kraft
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Jeff A
authors.initials: JA
authors.lastname: Rappaport
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA.
authors.forename: Adam E
authors.initials: AE
authors.lastname: Snook
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Lynch
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, Pennsylvania, USA scott.waldman@jefferson.edu.
authors.forename: Scott A
authors.initials: SA
authors.lastname: Waldman
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001427:Bacterial Toxins / Q000378:metabolism*; D006152:Cyclic GMP / Q000378:metabolism; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000378:metabolism; D003967:Diarrhea / Q000378:metabolism; D004195:Disease Models, Animal; D054307:Enterotoxigenic Escherichia coli / Q000378:metabolism / Q000502:physiology*; D004768:Enterotoxins / Q000378:metabolism / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D004927:Escherichia coli Infections / Q000382:microbiology* / Q000503:physiopathology; D029968:Escherichia coli Proteins / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D000074261:Receptors, Enterotoxin; D050705:Receptors, Guanylate Cyclase-Coupled / Q000378:metabolism*; D018000:Receptors, Peptide / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology
chemical_list: D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D018000:Receptors, Peptide; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; C000613654:GUCY2C protein, human; C000613655:Gucy2c protein, mouse; D000074261:Receptors, Enterotoxin; D050705:Receptors, Guanylate Cyclase-Coupled; D006152:Cyclic GMP