At the Wyss Institute for Biologically Inspired Engineering at Harvard University, in the Longwood medical neighborhood in Boston, researchers have reached a biotech milestone with tremendous potential for future drug testing and development. Instead of resorting to animals for testing, they may soon be using a simulated organ that lives on a chip. It has mechanical and biological (cellular) parts, and yes, it breathes, thanks to a vacuum system that pumps air through. The bio-inspired micro-device has gone through several tests recently to assess its accuracy in mimicking the human lung when bacteria or potentially toxic drugs are introduced. Results: Positive. The lung-on-a-chip replicates responses found in animal models and observations of human lung function. Indeed, because the device uses human lung and blood vessel cells, it acts may act more like a lung in a human body than lab animals.