STAT3 signaling in immunity.

The transcriptional regulator STAT3 has key roles in vertebrate development and mature tissue function including control of inflammation and immunity. Mutations in human STAT3 associate with diseases such as immunodeficiency, autoimmunity and cancer. Strikingly, however, either hyperactivation or inactivation of STAT3 results in human disease, indicating tightly regulated STAT3 function is central to health. Here, we attempt to summarize information on the numerous and distinct biological actions of STAT3, and highlight recent discoveries, with a specific focus on STAT3 function in the immune and hematopoietic systems. Our goal is to spur investigation on mechanisms by which aberrant STAT3 function drives human disease and novel approaches that might be used to modulate disease outcome.