A Harvard research team led by Laurie Glimcher, Irene Heinz Given professor of immunology at the Harvard School of Public Health and a Harvard Medical School professor of medicine, two years ago discovered a molecule that they named T-bet. T-bet seemed to help control the immune system response by determining the actions of helper T cells, which are orchestrators of the immune response to disease. Glimcher’s team studied mice that were engineered to lack T-bet. The mice, they found, had an uneven immune system response. Furthermore, the mice spontaneously developed the symptoms of asthma. The finding by Glimcher and her team helps to prove the case for T-bet as an important therapeutic target in several diseases, and also provides a new model for studying asthma.