To do this, the group took blood from people with melanoma and isolated a group of immune cells called T cells. They then modified those cells so that they could find and then destroy the cancerous cells.
What they found pointed to the use of blood-forming stem cells as an improved form of the therapy. Although the modified T cells did very effectively fight the cancer, their effect disappeared after about 90 days.
A press release from UCLA quotes Antoni Ribas, who was one of the authors on the study published online today in Cancer Discovery.
“One of the possible approaches to resolve the problem identified by this study is to use engineered blood stem cells instead of the peripheral blood used in the original trials with this therapy with the hope that the engineered blood stem cells will provide a renewable source of engineered T cells.” This approach is being moved forward into the clinic with clinical trials expected to open in two years.Ribas has a Disease Team award from CIRM to modify a patient’s blood-forming stem cells. When the team puts those cells back into the patient, the cells will form all the cells of the blood system including new red blood cells and new immune cells. Because the patient will now have an ongoing supply of the modified T cells, the group expects that the cells’ therapeutic effects will last longer than when they simply gave the patient’s short-lived modified T cells.
The group hopes to start clinical trials in the next two years.