Medical experts have been baffled by what causes asthma. Most of them favor the idea that it stems from "helper" cells that have gone awry. But researchers at Harvard Medical School have come up with convincing evidence that the answer lies in a special type of natural "killer" cell.
We were very, very surprised," admits Dale Umetsu, a professor of pediatrics at the Medical School and at Harvard-affiliated Children's Hospital in Boston. "People have been confused about which cells in the lungs are responsible for all these years. Now, we have to rethink the results of so many studies. Our new findings were totally unexpected."
