Developmental role of macrophages modelled in human pluripotent stem cell derived intestinal tissue

Abstract

Macrophages populate the embryo early in gestation but their role in the developmental process remains largely unknown. In particular, specification and function of macrophages in intestinal development remain unexplored. To study this event in human developmental context, we derived and combined human intestinal organoid and macrophages from pluripotent stem cells. Macrophages migrated into the organoid, proliferated, and occupied the emerging micro-anatomical niches of epithelial crypts and ganglia. They also acquired a similar transcriptomic profile to fetal intestinal macrophages and displayed tissue macrophage behaviors, such as recruitment to tissue injury. Using this model, we show that macrophages reduce glycolysis in mesenchymal cells and limit tissue growth without affecting tissue architecture, in contrast to the pro-growth effect of enteric neurons. In short, we engineered an intestinal tissue model populated with macrophages, and we suggest that resident macrophages contribute to regulation of metabolism and growth of the developing intestine.

Eicosatetraynoic Acid Regulates Pro-Fibrotic Pathways in an Induced Pluripotent Stem Cell Derived Macrophage:Human Intestinal Organoid Model of Crohn’s Disease

“…Our proposed studies have begun to address this barrier, by testing the novel concept that iPSC lines prepared from CD patients will yield a macrophage:organoid co-culture system which will capture critical inflammatory responses linked to anti-TNF response. 5-7,10,26 We found that LPS stimulated iPSC-derived macrophages exhibited a global pattern of gene expression and cytokine production highly relevant to refractory CD. 1-4 A small molecule prioritized by our perturbagen analysis, ETYA, exerted key anti-inflammatory and anti-fibrotic effects.…”

“…26,32,33 It recently been reported that co-cultured macrophages may be stably incorporated into the transplanted HIO under these conditions. 26 It will be important in future studies to take this approach, to test whether specific CD patient genetic profiles, and candidate small molecules including ETYA, exert significant effects upon tissue architecture in the murine iPSC-derived macrophage:HIO transplantation system. Derivation of iPSC from PBMC eliminates confounding epigenetic effects within primary tissues, providing an integrated model of genetic effects linked to important clinical phenotypes including anti-TNF response.…”

“…32 Under these conditions, over 12 weeks the full sub-mucosa and smooth muscle layers of the intestine develop, recapitulating the collagen architecture of CD strictures. 26,32,33 It recently been reported that co-cultured macrophages may be stably incorporated into the transplanted HIO under these conditions. 26 It will be important in future studies to take this approach, to test whether specific CD patient genetic profiles, and candidate small molecules including ETYA, exert significant effects upon tissue architecture in the murine iPSC-derived macrophage:HIO transplantation system.…”

“…CD patient iPSC-derived human intestinal organoids (HIO) co-cultured with iPSC-derived macrophages are an attractive experimental model for human CD. 5-7,26 HIO derived from iPSC contain epithelial cells and fibroblasts and increase collagen production in response to TGFβ. 5-7 We found that LPS stimulated iPSC-derived macrophages expressed a global pattern of gene expression enriched in CD ileal inflammatory macrophages, 1 and induced a pro-fibrotic gene program with collagen production in HIO co-culture.…”