The latest immunotherapies to fight cancer are barely on the market, and already researchers at the University of Minnesota are looking at the next generations that could increase the capacity of the human body to fight off deadly tumors on its own.

U researchers are building on existing discoveries with NK cells, or natural killer cells, because their ordinary function is to sweep through the body and eliminate impurities.

They hope to use molecular modification to activate the NK cells and then make them “sticky” so they find and bond to cancer cells. A third goal of the Trispecific Killer Engager approach, or TriKE, is to stimulate the NK cells to replicate themselves, said Daniel Vallera, an immunology researcher at the U.

The idea is to “insert a molecule that could stimulate the NK cells to expand,” Vallera said. “Instead of having one cell for your army, you would have an entire army of cells for your army that would be fighting the cancer.”

The U reached a deal this summer with Oxis Biotech Inc. to commercialize a TriKE approach and guide it through the federal regulatory process to prove it safe and effective.

Immunotherapy refers to treatments that stimulate the body’s own immune system to fight disease. Other approaches have shown promise in cancer care, but one problem is that they are extraordinarily expensive, Vallera said. Another is that stimulating the immune system often results in unwanted side effects and consequences.

“Its always been a double-edged sword,” Vallera said. “Every time you hyper-stimulate the immune system you get symptoms [or allergic reactions or side effects]. It’s been very difficult to control that.”

Human clinical trials required by the U.S. Food and Drug Administration are being scheduled. Vallera said the TriKE approach will initially be tested against acute myeloid leukemia, a cancer of the bone marrow and blood that is easier than other cancers to target with this experimental therapy.

Success is no sure thing; tests in animal models of the experimental medication’s toxicity have been challenging, Vallera acknowledged.

But if the approach works against leukemia, he said, it should eventually work against cancers of the breast, colon, kidney and other organs.