Seven out of 10 people who were administered specially treated lymphocytes shortly after undergoing living-donor liver transplants at Hokkaido University Hospital have remained in good health without having to rely on immunosuppressive drugs, researchers said Thursday.

Currently, patients who undergo organ transplants have to take immunosuppressants for the rest of their life. Such drugs can bring a variety of side effects, including increased risks of infections, cancers and organ failures.

In a pilot study covering 10 people in their 30s through their 60s, researchers at Hokkaido University and Juntendo University drew what's called "regulatory T cells," which control autoimmunity and influence the response of the immune system, from patients' blood, cultured them and injected them back into their bodies.