New devices may help bring drugs to market faster
One of the most challenging aspects of drug development is testing. Scientists are forced either to experiment on whole animals, which is expensive, raises ethical issues and may not predict effects in humans, or to perform tests on microscopic human cells found in tissue cultures, which have been altered to live forever and bear little relation to actual living, breathing people. But researchers are working on a new technique to help bridge that gap: microchips that simulate the activities and mechanics of entire organs and organ systems. These “organs on a chip,” as they are called, are typically glass slides coated with human cells that have been configured to mimic a particular tissue or interface between tissues. Developers hope they could bring drugs to market more quickly and, in some circumstances, perhaps even eliminate the need for animal testing.
The chips are still in their early stages, but investigators are translating more and more body parts to the interface. Last summer bioengineers at Harvard University wrote in the journal Science that they had created a device that mimics a human lung: a porous membrane surrounded by human lung tissue cells, which breathes, distributes nutrients to cells and initiates immune responses. In November 2010 Japanese researchers announced online in Analytical Chemistry that they had built a chip that simultaneously tests how liver, intestine and breast cancer cells respond to cancer drugs, and in February 2010 scientists publishing in the Proceedings of the National Academy of Sciences USA developed a microscale replica of the human liver that allowed them to observe the entire life cycle of hepatitis C, a virus that is difficult to observe in cultured cells.