Controlling Intestinal Organoid Polarity using Synthetic Dynamic Hydrogels Decorated with Laminin-Derived IKVAV Peptides

Abstract

Intestinal organoids are three-dimensional cellular structures that are cultured in laminin-rich Matrigel, yielding organoids with correct, basal-out polarity. Removal of Matrigel results in organoids with reversed, apical-out polarity, demonstrating its vital role. However, Matrigel's composition is ill-defined, and its pathogenic origin poses challenges in reproducibility. Therefore, we here introduce a fully synthetic dynamic hydrogel that presents the IKVAV peptide as a laminin-mimic for guiding intestinal organoid polarity in a minimalistic, controlled manner. The ureido-pyrimidinone moiety is used to form supramolecular hydrogels that have orthogonal control over properties, like stiffness, ligand type and concentration. It is found that the IKVAV peptide combined with integrin activating antibody TS2/16 controls intestinal organoid polarity. Increasing hydrogel dynamics (stress-relaxing half-life time of ≈1000 to 30 s) further supports the growth of intestinal organoids with correct polarity, while a bulk level of stiffness (G’ ≈0.7 kPa) is crucial to offer mechanical support. Through manipulation of integrins, it is revealed that the IKVAV-organoid interaction is integrin β1-mediated. Our findings demonstrate the essential role of the IKVAV motif in guiding intestinal organoid polarity in synthetic dynamic hydrogels – paving the way for the future design of synthetic systems to culture complex living tissue.