JDRF-funded scientist Diane Mathis has demonstrated that immune cells called regulatory T cells play a role in preventing type 1 diabetes. In the journal Immunity, she described how regulatory T cells control the progression of diabetes in mice. She showed that the cells rein in the autoimmune attack on the pancreas by altering the activity of another key immune cell—called a “natural killer” cell. When regulatory T cells were unavailable to block them, the natural killer cells released a molecule that set in motion the aggressive immune attack that leads to diabetes. The findings suggest that drugs or therapies that target natural killer cells might be effective in preventing or altering the course of the disease. Dr. Mathis is Director of the JDRF Center on Immunological Tolerance in Type 1 Diabetes at Harvard Medical School.