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Enteric neurons are critical in maintaining organ homeostasis within the small intestine, and their dysregulation are implicated in gastrointestinal disorders and neurodegenerative diseases. Most in vitro models lack enteric innervation, limiting basic discovery and disease modeling research. Here, a high‐throughput 3D microphysiological system (MPS), or organ chip is presented that supports a primary epithelial monolayer interfacing directly with encapsulated primary enteric neurons. The device features twelve 3D MPSs per device and gravity‐driven flow via a laboratory rocker to induce biomimetic shear stress on the epithelium culture and provide continuous nutrient presentation. Intestinal and neural tissue exhibited expected morphologies. Neural gene upregulation in the epithelium suggests RNA contamination from proximal enteric neurons extending neurites toward the epithelial monolayer. With the enteric nervous system (ENS), barrier integrity significantly increased for both TEER and permeability assays, a 1.25‐fold greater resistance and 10% lower permeability as compared to epithelium cultured alone. The presence of the ENS resulted in a significant (1.4‐fold) reduction in epidermal growth factor (EGF). Additionally, several key epithelial genes are compared between duodenal tissue and epithelial monolayers with and without neurons present. Results demonstrated changes in cytokine gene expression and WNT pathways, highlighting innervation is essential to create more biomimetic and physiologically relevant in vitro models. [ABSTRACT FROM AUTHOR]

Self‐organized microvascular networks (MVNs) have become key to the development of many microphysiological models. However, the self‐organizing nature of this process combined with variations between types or batches of endothelial cells (ECs) often lead to inconsistency or failure to form functional MVNs. Because interstitial flow (IF) has been reported to play a beneficial role in angiogenesis, vasculogenesis, and 3D capillary morphogenesis, the role IF plays during neovessel formation in a customized single‐channel microfluidic chip for which IF has been fully characterized is systematically investigated. Compared to static conditions, MVNs formed under IF have higher vessel density and diameters and greater network perfusability. Through a series of inhibitory experiments, this study demonstrates that IF treatment improves vasculogenesis by ECs through upregulation of matrix metalloproteinase‐2 (MMP‐2). This study then successfully implements a novel strategy involving the interplay between IF and MMP‐2 inhibitor to regulate morphological parameters of the self‐organized MVNs, with vascular permeability and perfusability well maintained. The revealed mechanism and proposed methodology are further validated with a brain MVN model. The findings and methods have the potential to be widely utilized to boost the development of various organotypic MVNs and can be incorporated into related bioengineering applications where perfusable vasculature is desired. [ABSTRACT FROM AUTHOR]

Microphysiological systems (MPSs), based on microfabrication technologies and cell culture, can faithfully recapitulate the complex physiology of various tissues. However, 3D tissues formed using MPS have limitations in size and accessibility; their use in regenerative medicine is, therefore, still challenging. Here, an MPS‐inspired scale‐up vascularized engineered tissue construct that can be used in regenerative medicine is designed. Endothelial cell‐laden hydrogels are sandwiched between two through‐hole membranes. The microhole array in the through‐hole membranes enables the molecular transport across the hydrogel layer, allowing long‐term cell culture. Furthermore, the time‐controlled delamination of through‐hole membranes enables the harvesting of cell‐cultured hydrogel constructs without damaging the capillary network. Importantly, when the tissue constructs are implanted in a mouse ischemic model, they protect against necrosis and promoted functional recovery to a greater extent than implanted cells, hydrogels, and simple gel–cell mixtures. [ABSTRACT FROM AUTHOR]