This isn't the first time engineered immune cells, called T-cells, have been used to treat, or even cure, blood cancers. This T-cell therapy is called CAR-T, and it's been studied for a number of years already. But in the past, those cells have always come from the patient. That requires a logistical headache, not to mention a medical risk: the patients have to wait while their blood is shipped to a biotech company—sometimes overseas—modified, then shipped back. Still, they work surprisingly well, permanently curing roughly half of patients.
Doing the same thing with someone else's blood opens the possibility for a universal cure that's faster and less expensive than personalized treatments. Patients could get the treatment immediately at a fraction of the price: according to the MIT Technology Review, one dose could be around $4,000 instead of the $50,000 it takes to alter a patient's own cells.