According to new transplant research in Sweden, an old cancer drug, Zebularine, may help to prevent rejection after transplantation. Rejection of the new tissue or organ has long been a problem for patients after receiving a transplant from an organ donor. However, this new discovery may help scientists to develop new anti-rejection treatments that will provide excellent results for transplant patients.

Researchers from Lund University's Rausing Laboratory recently conducted the study on Zebularine. The researchers have been researching brain tumors for many years, including studies of the effects of Zebularine, an old tumor drug that was developed back in the 1960s by researchers in the United States.

According to the senior professor of neurosurgery involved in this study, Leif Salford, “by chance we discovered it had completely unexpected effects on the immune system.”

In the recent study, which was published in the PLOS ONE scientific journal, the Swedish researchers took a group of rats, transplanting the islets of Langerhans from a group of healthy rats into rats that were made diabetic. Researchers divided the rats into two different groups.

While one group of rats received no treatment at all, Zebularine was used to treat the other group of rats on a daily basis. The study found that the rats receiving daily treatments of Zebularine lived much longer than the rats that received no treatment.

According to Dr. Henrietta Nittby, one of the researchers who took part in the study, “It is very interesting that we only treated [the rats] with Zebularine for two weeks, but the effects of the treatment could be observed throughout the 90-day follow-up period.”

The research team was excited that these findings suggest the drug helped to repress the immune system, yet it also provided targeted treatment with no side effects observed in the rats.

After these exciting findings, researchers on the team are working to refine this treatment further, working to teach dendritic cells (special immune system cells) how to accept specific proteins by using this tumor drug. Accomplishing this would allow the treatment to be better targeted for improved results.

"If we succeed with that, we believe it could be of clinical significance both to prevent rejection of transplanted organs and to stop the body attacking its own tissue in autoimmune diseases," Salford said. "If this becomes a reality, I hope large groups of patients could be spared the lifelong treatment that is currently necessary to keep the immune system in check.”

Zebularine shows great promise in preventing rejection after transplantation, but it also may prove useful for treating autoimmune diseases, such as rheumatoid arthritis or Type 1 diabetes, by curbing the attacks of the body upon itself. If the team makes further progress using this drug, they hope that many patients undergoing organ transplants will no longer have to undergo long-term immune-suppressing treatments.