Measuring the Microgravity Response in Epithelial Tissue Barrier Function: A Path to Flight

Epithelial tissue serves an important barrier function in the body. In spaceflight, exposure to microgravity could disrupt this barrier and cause significant health problems for astronauts. There is a need for real-time monitoring of the epithelial barrier function to determine when countermeasures are needed. One possibility for conducting this measurement in vivo is the use of potential difference (PD) probes, which have been developed for use on Earth. Here, we outline the path to flight for the use of PD probes in astronauts in space. This begins with the conceptual design of an orbital flight test; this experiment will identify the magnitude and timeline of the change in epithelial barrier function that results from exposure to microgravity. Results inform the design of a space-capable PD probe such that it can detect microgravity-induced changes to the epithelial barrier. This will enable integration of the PD probe into the spaceflight medical system, changing the landscape of exploration medicine and improving astronaut health outcomes through the use of a minimally invasive in vivo monitoring method for microgravity-induced epithelial barrier dysfunction.