The foundations of cancer treatment have been surgery, chemotherapy, radiation therapy and targeted therapies homing in on specific molecular changes seen primarily in cancer cells. More recently, immunotherapies that enlist and strengthen the power of a patient’s immune system to attack tumors have emerged
A rapidly emerging immunotherapy approach is called adoptive cell transfer (ACT): collecting and using patients’ own immune cells to treat their cancer and, thus far, the type of ACT that has advanced the furthest in clinical development is called CAR T-cell therapy.
The backbone of CAR T-cell therapy is T cells, which are often called the workhorses of the immune system because of their critical role in orchestrating the immune response and killing cells infected by pathogens.
The therapy requires drawing blood from patients and separating out the T cells. Next, using a disarmed virus, the T cells are genetically engineered to produce receptors on their surface called chimeric antigen receptors, or CARs. These special receptors allow the T cells to recognize and attach to a specific protein, or antigen, on tumor cells.
Once the collected T cells have been engineered, they are “expanded” in the laboratory into the hundreds of millions and infused into the patient
If all goes as planned, the engineered cells further multiply in the patient’s body and, with guidance from their engineered receptor, recognize and kill cancer cells that harbor the antigen on their surfaces.
Source National Cancer Institute