Therapy flags DNA typos to rev cancer-fighting T cells
Disabled spell-checker identifies patients who may benefit from immune therapy
![Keytruda](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2017/06/060917_ti_keytruda_main_free.jpg?fit=860%2C460&ssl=1)
UNLEASHED An antibody sold as the drug Keytruda helps turn on cancer-fighting T cells. Tumors (red) can use PD-1 proteins (yellow, orange) to lock onto T cells (white) and shut them down. The antibody blocks PD-1 proteins, freeing T cells to attack the cancer.
Courtesy of Merck & Co.