Immune System: The Body's New Super Hero?
The journal Science Translational Medicine recently published a study showing promise for immunotherapy in treating recurrent acute myeloid leukemia (AML) in adults. The study’s lead author Rizwan Romee, MD, and senior author Todd Fehniger, MD, PhD, from the division of oncology of Washington University School of Medicine, barely let the ink dry before they were on to their next challenge. In collaboration with Jeffrey Bednarski, MD, PhD, pediatrics, they submitted a proposal to and received funding from the Children’s Discovery Institute to pursue the same study in children.
“These are patients whose cancer does not respond to the current chemotherapy drugs, and for whom a bone marrow transplant failed,” says Dr. Bednarski. “Once we get to that stage, there really isn’t very much we can offer them. We think they deserve more options.”
Drs. Romee and Fehniger explain that their small, phase 1, “first in human” clinical trial provides evidence that the immune system’s “natural killer” (NK) cells can be dialed up in the laboratory, trained to recall that activation and then be unleashed to destroy cancer cells in some patients. Responses to the treatment were observed in five of the nine patients that could be evaluated.
Everyone has NK cells in their body. The fact that they have a tendency to pounce and kill AML cells make them of special interest. They were discovered in the 1970s by two groups of researchers in the United States and Scandinavia. Since then, much effort has gone into understanding their biology and ways to put them to better use.
“It wasn’t until recently that we figured out some new ways to train these cells and make them better at responding to leukemia cells,” says Dr. Bednarski. “So, with Rizwan and Todd’s discovery, and support from the CDI, the next chapter of NK cell biology starts right here at the School of Medicine.”
The secret sauce of NK activation is to take three chemical signals (called interleukins 12, 15 and 18) that transform them into “cytokine-induced memory-like” NK cells that are more potent in fighting leukemia.
“Soldiers are never sent into battle without basic training,” Dr. Romee told The Source, a School of Medicine publication. “You can think of the activation period in the laboratory as a boot camp, exposing the cells to some of the conditions and signals they will encounter in the patient’s body. So when NK cells see the real cancer the first time, they remember their training and respond more effectively than cells that don’t have this exposure.”
Once the researchers get through all the regulatory stages necessary before a human trial can begin, CDI funding will allow them to apply this personalized immunotherapy to potentially benefit children. If effective, the treatment will brighten the prognosis for AML patients to the level currently experienced by children diagnosed with another type of leukemia, acute lymphoblastic leukemia (ALL).