Immune system seems to remember cancer in people who've never had it
Echoes of past encounters with leukemia flow through the veins of people who have never suffered from the disease, a study suggests. The immune systems of cancer-free people may have gathered antileukemia forces by mounting preemptive strikes against cells that were on their way to becoming cancerous. Leukemia patients, on the other hand, carry meager signs of resistance.
“Perhaps we’ve all had a bit of precancerous disease,” says immunologist Mark Cobbold of the University of Birmingham in England, who led the study with Birmingham colleague Hugo De La Peña. Just as immune cells reflect a person’s history of viral infections, the fingerprint of cancer exposures could lie there as well, Cobbold says.
After an encounter with any pathogen, a fraction of immune cells that fought in the battle stick around, lying in wait for the next attack. Cobbold, De La Peña and their colleagues found in healthy people killer immune cells that appeared to have been