Researchers at the Technical University of Munich (TUM) have developed a new PET-based technique for tracking modified immune cells used in immunotherapy, which could significantly enhance treatment safety and efficacy.

This innovative method involves inserting an artificial receptor into modified immune cells, allowing for visualization using PET imaging and a non-toxic radioactive contrast agent known as a radioligand.

The radioligand binds exclusively to the modified cells and their descendants, enabling real-time monitoring of their behavior within the body.

Experiments conducted on mice demonstrated that the modified CAR-T cells successfully migrated to diseased tissue and proliferated, with the radioligand being safely excreted without interfering with other biological processes.

Current methods do not allow physicians to effectively track the behavior of modified immune cells, raising concerns about their migration, replication, and potential to attack healthy tissue.

While the technique shows promise, further testing in clinical trials is necessary to verify its safety and efficacy before it can be applied to human patients.

The researchers believe this method could provide critical insights for both basic research and clinical applications of immunotherapy and gene therapy.

Additionally, this monitoring technique has potential applications in tracking gene therapies that utilize viruses to alter genetic information in cells.

The development is supported by the German Federal Ministry of Research, Technology and Space, aiming to reduce the number of laboratory animals needed for research by enabling continuous monitoring during experiments.

The researchers aim for this technique not only to advance medical research but also to promote animal welfare by minimizing the use of laboratory animals.

Custom-tailored cell therapies like CAR-T-cell therapy are increasingly important when standard cancer treatments fail, involving the genetic modification of patient-derived immune cells to attack tumors.

The project was led by Professor Wolfgang Weber, who collaborated with multiple experts from TUM, including Dirk Busch and Katja Steiger, to develop this groundbreaking technique.