Immunotherapy has been considered to treat cancers by activation of T cells. However, whether immunotherapy is effective in suppressing aging was unknown. Dr. Nakanishi’s group in Tokyo University found first time that immunotherapy is effective not only in treating cancers but also in treating aging. As aging is one of the diseases, immunotherapy might be used to keep our own bodies young and healthy without developing organ disorders.
Background
Immunotherapy is a type of cancer treatment that uses the body’s own immune system to fight cancer cells. It is a form of treatment that uses substances to stimulate or suppress the immune system to help the body fight cancer. It works by helping the immune system recognize, target, and attack cancer cells while leaving healthy cells intact. Immunotherapy treatments vary, but they typically involve the use of drugs, vaccines, and other substances to stimulate the immune system to target and destroy cancer cells. These treatments can be used alone or in combination with other cancer therapies, such as chemotherapy, radiation therapy, or surgery. In the clinic, immunotherapy is often used to treat cancers that have not responded to other treatments, or to help reduce the risk of cancer recurrence after other treatments have been completed. It is a promising area of research and is being actively studied in clinical trials for the treatment of a wide range of cancers.
Discovery
This study by Dr. Nakanishi revealed the molecular basis behind the accumulation of senescent cells, which is a major cause of age-related inflammation and predisposes to a variety of age-related diseases. They showed that senescent cells heterogeneously express the immune checkpoint protein PD-L1, which allows senescent cells to be resistant to T cell surveillance. Administration of PD-1 antibody (one of the immunotherapies used for cancer treatment) to aging mice or a mouse model with normal livers or induced nonalcoholic steatohepatitis by fat diet reduced the number of senescent cells in a T cell-dependent manner, ameliorating various aging-related phenotypes including the reduction of lipid accumulation in the liver. These findings suggest that targeting PD-L1+ senescent cells by immunotherapy may be a promising strategy for anti-aging therapy.
