How natural killer (NK) cells, which play important roles in destroying cancerous and virally infected cells in the body, are restrained is described in a paper published online this week in Nature Immunology. By better understanding how NK cells can be regulated, these cells’ function can be utilized for therapeutic purposes such as tumor cell killing.

Mark J Smyth and colleagues find that mouse and human NK cells have a little-known receptor molecule on their surface called CD96. By genetically removing CD96 on mouse NK cells, the authors see that NK cells become rampantly activated. While this can result in an over-exuberant and harmful inflammatory response, the hyperactive CD96-deficient NK cells are also far more efficient at killing cancer cells in several different mouse models.