February 23, 2017 0930 GMT
By unlocking the natural fighter function of immune T cells when they are moving through the bloodstream, researchers can create larger numbers of T cells to recognize and target proteins present in most cancers, UPI reported.
Dr. Peter Cohen, a Mayo Clinic immunotherapist and coauthor of the study, said, "Even though it is relatively easy to collect billions of T cells directly from patient blood, it has historically proved difficult or impossible to unleash those T cells' natural ability to recognize and target cancer cells.”
Dr. Nora Disis, an immunotherapist at the University of Washington and coauthor of the study, explained how the new method works.
"Our method strictly employs natural signals to activate the immune blood cells outside the body.
"This gives rise to expanded armies of T cells, which specifically recognize proteins that are present on cancer cells and which can be reinfused into patients for therapeutic evaluations in future clinical trials."
Researchers tested the ability to stimulate T cell responses against MUC1, a protein expressed by a majority of cancers including breast, pancreatic, lung, colorectal, ovarian, kidney, bladder and multiple myeloma.
The results showed that T cells traveling within the bloodstream naturally remained in a resting state unless they were exposed to alarm signals triggered by serious infections.
The T cells, once outside the body, were safely exposed to alarm signals to unlock their fighter function.
The T cells were exposed to MUC1, HER2/neu, CMVpp65 or other cancer proteins and only took three weeks to grow out natural T cell armies trained to target cancer expression in the proteins.
Sandra Gendler, PhD, Mayo Clinic immunologist and coauthor of the study, said, "Our culture method is similar to performing a vaccination procedure entirely outside the body, and it was successful for all three proteins.
"The cancer-associated proteins we have tested so far already target the majority of human cancers, and it is likely that this culture method will extend to many additional proteins present on cancer cells."