OrganEx: What Will It Mean?

Abstract

In April 2019 Yale Professor Nenad Sestan’s “BrainEx” experiments startled the world (Vrselja 2019). Four hours after pigs were decapitated, researchers perfused the pigs’ brains using what they called “BrainEx,” a machine that circulated a fluid made up mainly of a synthetic hemoglobin. Astoundingly, many of the cells in the pig brains “came back to life” even though conventional wisdom had been that brain cells die, irrevocably, after about ten minutes without oxygen. The researchers found no signs of organized neuronal firings, no pattern on an electroencephalogram (“EEG”), and concluded “This is not a living brain, but it is a cellularly active brain...” (Thompson 2019). BrainEx was a sensation but Sestan’s team has published nothing more about it and, after a few commentaries (Farahany, Greely, and Giattino 2019; Youngner and Hyun 2019), it quietly receded. In early August 2022, though, Sestan’s team caused another big gasp with the publication of the results of its experiments with “OrganEx”, using a similar device and fluid to BrainEx, but for the entire body, not just the brain (Andrijevic et al. 2022). In this experiment, pigs were anesthetized and then killed with induced cardiac arrest. After about an hour near body temperature, the dead pigs’ blood vessels were filled with a perfusate similar to BrainEx’s. And, like BrainEx, OrganEx worked, at least somewhat, attracting media attention and raising hopes, fears, and issues.