A microphysiological system for studying barrier health of live tissues in real time.

Epithelial cells create barriers that protect many different components in the body from their external environment. Increased gut barrier permeability (leaky gut) has been linked to several chronic inflammatory diseases. Understanding the cause of leaky gut and effective interventions are elusive due to the lack of tools that maintain tissue's physiological environment while elucidating cellular functions under various stimuli ex vivo. Here we present a microphysiological system that records real-time barrier permeability of mouse colon in a physiological environment over extended durations. The system includes a microfluidic chamber; media composition that preserves microbiome and creates necessary oxygen gradients across the barrier; and integrated sensor electrodes for acquiring transepithelial electrical resistance (TEER). Our results demonstrate that the system can maintain tissue viability for up to 72 h. The TEER sensors can distinguish levels of barrier permeability when treated with collagenase and low pH media and detect different thickness in the tissue explant.