Killer upgrades

The advantages of NK cells first piqued cancer researchers' interest two decades ago, but issues such as the cells' inability to last long in the body hindered development. For those who received NK cells from such optimal cord-blood units, the one-year survival rate was 69%. About 15 years ago, for example, researchers at Washington University School of Medicine found that a particular blend of cytokines could reprogram mouse NK cells to become more easily activated when they are stimulated for a second time. The combination improves the metabolism of NK cells, protects them from oxidative stress, enhances their cancer-killing activity and turns on genes for surface proteins that improve their ability to home in on tumour sites.