Tasuku Honjo

Tasuku Honjo (born 1942) is a Japanese physician-scientist and immunologist who shared the 2018 Nobel Prize in Physiology or Medicine with James P. Allison. Born in Kyoto, he took his medical degree at Kyoto University in 1966 and a doctorate there in 1975, and then worked at the Carnegie Institution of Washington and the United States National Institutes of Health. He held professorships at Osaka University and, from 1984, at Kyoto University, and served as president of the Japanese Society for Immunology. In 1992 he first identified PD-1 as an inducible gene on activated T lymphocytes, a discovery that underlies cancer immunotherapy by PD-1 blockade. He also cloned the cytokines IL-4 and IL-5, explained class switch recombination of antibody genes, and discovered activation-induced cytidine deaminase in 2000. He has also spoken publicly in support of HPV vaccination in Japan.