To monitor cancer therapy, researchers tag CAR T cells with imaging markers

With CAR T cell therapy, a patient’s own immune cells are genetically modified and inserted back into the body to find and kill cancer. This form of immunotherapy has already revolutionized some cancer treatments, but once the CAR T cells are inside a patient, where do they go? How do doctors know that they have successfully reached their target and that they are continuing to fight disease weeks, months, or even years later?

rendering of a t cell

Scientists have now discovered a new way to track CAR T cells in the body, according to a study led by researchers in the Perelman School of Medicine. The researchers genetically engineered CAR T cells with molecular tags, which they were able to monitor in an animal model using position emission tomography imaging. The results were published in the journal Molecular Therapy.

“Currently, the only way to know whether a gene or cell therapy is still present in the body is to regularly biopsy tumors or draw blood, which offer very crude measurements of the therapy. With our technology, clinicians would be able to see, quantitatively, the number and location of CAR T cells that have lasted in the body over time, which is an indicator of the therapy’s durability and potential efficacy,” says Mark Sellmyer, an assistant professor of radiology. “Imaging CAR T cells also will allow researchers to more easily test and modify therapies for many different types of disease in the research setting.”

Sellmyer co-led the study with Michael Farwell, an assistant professor of radiology, Michael Milone, an associate professor of pathology and laboratory medicine, and Sarah Richman, an attending physician at Children’s Hospital of Philadelphia.

Read more at Penn Medicine News.