Tasuku Honjo

is a Japanese immunologist. He is best known for his work of finding and naming the Programmed Cell Death Protein 1 (PD-1).
He is also known for his discovery of cytokines: IL-4 and IL-5, as well as the discovery of Activation-induced Cytidine Deaminase (AID).
He was elected as a foreign associate of the National Academy of Sciences in 2001. He is a member of German Academy of Natural Scientists Leopoldina (2003), and also as a member of the Japan Academy (2005). 
In 2018, he was awarded the Nobel Prize in Physiology or Medicine along with James P. Allison.