A Synthetic Hydrogel, VitroGel® ORGANOID-3, Improves Immune Cell-Epithelial Interactions in a Tissue Chip Co-Culture Model of Human Gastric Organoids and Dendritic Cells

Abstract

Immunosurveillance of the gastrointestinal epithelium by mononuclear phagocytes (MNPs) is essential for maintaining gut health. However, studying the complex interplay between the human gastrointestinal epithelium and MNPs such as dendritic cells (DCs) is difficult, since traditional cell culture systems lack complexity, and animal models may not adequately represent human tissues. Microphysiological systems, or tissue chips, are an attractive alternative for these investigations, because they model functional features of specific tissues or organs using microscale culture platforms that recreate physiological tissue microenvironments. However, successful integration of multiple of tissue types on a tissue chip platform to reproduce physiological cell-cell interactions remains a challenge. We previously developed a tissue chip system, the gut organoid flow chip (GOFlowChip), for long term culture of 3-D pluripotent stem cell-derived human intestinal organoids. Here, we optimized the GOFlowChip platform to build a complex microphysiological immune-cell-epithelial cell co-culture model in order to study DC-epithelial interactions in human stomach. We first tested different tubing materials and chip configurations to optimize DC loading onto the GOFlowChip and demonstrated that DC culture on the GOFlowChip for up to 20 h did not impact DC activation status or viability. However, Transwell chemotaxis assays and live confocal imaging revealed that Matrigel, the extracellular matrix (ECM) material commonly used for organoid culture, prevented DC migration towards the organoids and the establishment of direct MNP-epithelial contacts. Therefore, we next evaluated DC chemotaxis through alternative ECM materials including Matrigel-collagen mixtures and synthetic hydrogels. A polysaccharide-based synthetic hydrogel, VitroGel®-ORGANOID-3 (V-ORG-3), enabled significantly increased DC chemotaxis through the matrix, supported organoid survival and growth, and did not significantly alter DC activation or viability. On the GOFlowChip, DCs that were flowed into the chip migrated rapidly through the V-ORG matrix and reached organoids embedded deep within the chip, with increased interactions between DCs and gastric organoids. The successful integration of DCs and V-ORG-3 embedded gastric organoids into the GOFlowChip platform now permits real-time imaging of MNP-epithelial interactions and other investigations of the complex interplay between gastrointestinal MNPs and epithelial cells in their response to pathogens, candidate drugs and mucosal vaccines.

RGD-Functionalized Hydrogel Supports the Chondrogenic Commitment of Adipose Mesenchymal Stromal Cells

“…These results indicated that all hydrogel properties (both mechanical and biochemical) were favorable to maintain positive hASCs characteristics. Our results are in line with previous studies [ 52 , 53 ], showing different cell types (like immune, epithelial, and stem cells) encapsulated in VG-based hydrogels. The results demonstrated that these hydrogels were interesting matrices able to create a cell-friendly environment.…”

Culture of patient-derived multicellular clusters in suspended hydrogel capsules for pre-clinical personalized drug screening

“…In addition, higher fidelity of in vitro models has been achieved by vascularization [ 61 , 62 ], multicellular co-culture [ [63] , [64] , [65] ], tissue engineering [ [66] , [67] , [68] ], tissue decellularization [ 69 , 70 ] and genetic technologies [ [71] , [72] , [73] ]. It is expected that more components of the TME will be introduced into PDTOs in the future by applying these methods [ [74] , [75] , [76] ].…”

Everything You Always Wanted to Know About Organoid-Based Models (and Never Dared to Ask)

“…These technical advances enable optimizing the organoid cell size and differentiation, thus broadening the range of readout approaches that can be applied to organoids, for example, testing drugs or other host cell–derived secreted factors on disease-modeling organoids (eg, immune mediators). 130 , 131 It therefore is primordial to gather as much information as possible about the ECM biochemical (eg, composition, protein isoforms, signaling growth factors) and physical properties (eg, stiffness) appropriate for the tissue to be modeled. A few recent reviews have compiled advantageous characteristics about currently available animal tissue–derived, or synthetic hydrogels, in their ability to promote and sustain organoid culture.…”