Low Dose Radiation Research

The development of stem cell-based therapy relies on the availability of adequate supply of healthy donor-derived stem cells. Unfortunately, stem cell therapy faces a major challenge, which is that these cells suffer from premature aging and decreased functional and regenerative capacity when they are removed from the body.

Building on earlier CNL research which suggested that low-dose radiation could have a positive impact on stem cell performance, the Radiobiology team undertook a study to investigate the effects of low-dose radiation exposure on mesenchymal stem and progenitor cells, and endothelial colony forming cells. In the study, these cells were irradiated with varying levels of radiation, and aged in culture in a controlled manner, allowing us to monitor cell proliferation and functional changes.

The results show significant potential for the use of low-dose radiation to improve stem cell therapy. While non- irradiated stem cells aged significantly, cells treated with low-dose radiation demonstrated improved proliferation, mobility and chondogrenic differentiation capacity. Overall, these results provide the first evidence of delayed aging and improved functional properties of these specific stem cells.

CNL is now undertaking further studies to better understand the mechanisms behind the performance improvements.

While exposure to high doses of radiation is clearly dangerous to human beings, there is growing evidence that low doses of ionizing radiation may – surprisingly – be beneficial for people. This experience actually stimulates the activation of repair mechanisms that have long lasting impacts which help protect people against disease. Our studies have shown that low doses don’t pose a threat to humans. Instead, this form of radiation improves your body’s ability to heal itself by boosting your immune system.

Over the years, CNL has conducted studies that show significant improvements from exposure to low dose radiation, particularly with older specimens whose immune systems look much younger following the treatment. These results made us wonder whether we could apply this technique to medical therapies such as cancer treatment. More specifically, CNL considered the use of low dose radiation to supplement an existing form of cancer treatment, known as immune checkpoint therapy.

In simple terms, this type of therapy removes the ‘brakes’ from a person’s immune system. Normally, our immune system can differentiate normal cells from foreign cells by molecules known as “checkpoints”, which restrain the immune system when present on a cell. Unfortunately, cancer cells have the ability to conceal themselves from the immune system through the use of these checkpoints. By deactivating these brakes, we can boost our immune response against cancer cells. This therapy has already revolutionized the field, showing a great deal of promise in treating certain cancers.

CNL’s research is the first to suggest that low dose radiation can improve the efficacy of immune checkpoint therapy, which improves a new form of cancer therapy that’s already proven to be effective. CNL recently filed a provisional patent on combining these two therapies for the treatment of colon cancer.