Fibrosis is the formation of excess fibrous tissue in organs, a process associated with cardiovascular disease as well as heart dysfunction and kidney failure. Researchers discovered that a molecule called IL11 triggers fibrosis in human cells and in mice. Moreover, genetic deletion of Il11 protects against heart and kidney fibrosis and organ failure in mice. The findings suggest that IL11 could be a promising, safe therapeutic target for cardiovascular diseases. The study, published in Nature, was partly funded by NHLBI.