Niche-inspired synthetic matrices for epithelial organoid culture

Abstract

8Epithelial organoids are now an important tool in fields ranging from regenerative medicine to 9 drug discovery. Organoid culture requires Matrigel, a complex, tumor-derived, extracellular 10 matrix. An alternative completely synthetic matrix could improve culture reproducibility, clarify 11 mechanistic phenomena, and enable applications involving human implantation. Here, we 12 designed synthetic matrices with tunable biomolecular and biophysical properties that allowed us 13 to identify critical gel parameters in organoid formation. Inspired by known epithelial integrin 14 expression in the proliferative niche of the human intestine, we identified an a2b1 integrin-binding 15 peptide as a critical component of the synthetic matrix that supports human duodenal colon and 16 endometrial organoid propagation. We show that organoids emerge from single cells, retain their 17 proliferative capacity, are functionally responsive to basolateral stimulation and have correct 18 apicobasal polarity upon induction of differentiation. The local biophysical presentation of the 19 cues, rather than bulk mechanical properties, appears to be the dominant parameter governing 20 epithelial cell proliferation and organoid formation in the synthetic matrix. 21 . 22

The Microfluidic Environment Reveals a Hidden Role of Self-Organizing Extracellular Matrix in Hepatic Commitment and Organoid Formation of hiPSCs

“…The upregulation of ECM receptors, and particularly integrins, is recognized to be key for the formation of 3D organoids, particularly of endodermal origin ( Olabi et al., 2018 ; Hernandez-Gordillo et al., 2019 ). Therefore, we tested the potential of our hiPSC-derived IH cells exposed to the self-organizing ECM protein network in μF to generate hepatic organoids ( Figure 4 A), by harnessing a self-renewing medium recently optimized for hepatic progenitor cells directly isolated from fetal or adult tissue ( Hu et al., 2018a ).…”