A logic gate for cancer cells: immune cells taught to attack leukaemia and spare the healthy

After a stem-cell transplant cures leukaemia, nearly half of patients see it return — and the donor cells that rebuilt their blood are almost impossible to tell apart from the cancer. At Johns Hopkins, researchers built CAR T cells — immune cells engineered in the lab — with a two-signal 'logic gate': attack cells carrying the leukaemia marker CD33, but stand down when a second marker shows the cell came from the healthy donor. In lab dishes and in mice, the cells wiped out the leukaemia completely while leaving donor-type cells untouched. It is early, preclinical work, not yet tested in people — but it points to a far more precise way to treat relapse.

SDG 3 · Good health and well-being — Mechanism: tech innovation