Intestinal organoids: a model of intestinal fibrosis for evaluating anti-fibrotic drugs

Exp Mol Pathol. 2015 Jun;98(3):346-51. doi: 10.1016/j.yexmp.2015.03.033. Epub 2015 Mar 28.

Abstract

Background & aims: Intestinal fibrosis is a critical complication of Crohn's disease (CD). Current in vitro models of intestinal fibrosis cannot model the complex intestinal architecture, while in vivo rodent models do not fully recapitulate human disease and have limited utility for large-scale screening. Here, we exploit recent advances in stem cell derived human intestinal organoids (HIOs) as a new human model of fibrosis in CD.

Methods: Human pluripotent stem cells were differentiated into HIOs. We identified myofibroblasts, the key effector cells of fibrosis, by immunofluorescence staining for alpha-smooth muscle actin (αSMA), vimentin, and desmin. We examined the fibrogenic response of HIOs by treatment with transforming growth factor beta (TGFβ) in the presence or absence of the anti-fibrotic drug spironolactone. Fibrotic response was assayed by expression of fibrogenic genes (COL1A1 (collagen, type I, alpha 1), ACTA2 (alpha smooth muscle actin), FN1 (fibronectin 1), MYLK (myosin light chain kinase), and MKL1 (megakaryoblastic leukemia (translocation) 1)) and proteins (αSMA).

Results: Immunofluorescent staining of organoids identified a population of myofibroblasts within the HIO mesenchyme. TGFβ stimulation of HIOs produced a dose-dependent pro-fibrotic response. Spironolactone treatment blocked the fibrogenic response of HIOs to TGFβ.

Conclusions: HIOs contain myofibroblasts and respond to a pro-fibrotic stimulus in a manner that is consistent with isolated human myofibroblasts. HIOs are a promising model system that might bridge the gap between current in vitro and in vivo models of intestinal fibrosis in IBD.

Keywords: Drug screening; Fibrosis model; Myofibroblasts; Organoid; TGFβ.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / genetics
  • Actins / metabolism
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism
  • Cell Differentiation
  • Cells, Cultured
  • Collagen Type I / genetics
  • Collagen Type I / metabolism
  • Embryonic Stem Cells / cytology
  • Embryonic Stem Cells / drug effects
  • Fibronectins / genetics
  • Fibronectins / metabolism
  • Fibrosis / drug therapy
  • Humans
  • Intestines / drug effects*
  • Intestines / pathology
  • Myofibroblasts / cytology
  • Myofibroblasts / drug effects
  • Myofibroblasts / metabolism
  • Myosin-Light-Chain Kinase / genetics
  • Myosin-Light-Chain Kinase / metabolism
  • Organoids / drug effects*
  • Organoids / metabolism
  • Organoids / pathology
  • Pluripotent Stem Cells / cytology
  • Pluripotent Stem Cells / drug effects
  • Spironolactone / pharmacology*
  • Spironolactone / therapeutic use
  • Trans-Activators / genetics
  • Trans-Activators / metabolism
  • Transforming Growth Factor beta / pharmacology

Substances

  • ACTA2 protein, human
  • Actins
  • Calcium-Binding Proteins
  • Collagen Type I
  • FN1 protein, human
  • Fibronectins
  • MRTFA protein, human
  • Trans-Activators
  • Transforming Growth Factor beta
  • collagen type I, alpha 1 chain
  • Spironolactone
  • MYLK protein, human
  • Myosin-Light-Chain Kinase