Emil Raphael Unanue (September 13, 1934 – December 16, 2022) was a Cuban-American immunologist and Paul & Ellen Lacy Professor Emeritus at Washington University School of Medicine. He is a member of the National Academy of Sciences, the American Academy of Arts and Sciences and the Institute of Medicine. He previously served as chair of the National Academy of Sciences Section of Microbiology and Immunology. Area of expertise Unanue initiated a field of study known as antigen presentation; it is critical to the development of vaccines and underlies an understanding of microbial immunity and autoimmune diseases. In the late 1970s, it was recognized that T lymphocytes could not recognize antigen directly and instead required an interaction with another specialized cell known as the Antigen-presenting cell. Nobel Prize winners, Rolf Zinkernagel and Peter C. Doherty showed that this recognition also required the antigen-presenting cell to be from the same genetic background as the T-cell. That observation, called MHC restriction, led to a conundrum; namely, that the ability of a T cell to recognize foreign antigen also required that it recognize "self" With Paul M. Allen, the Robert L. Kroc Professor at Washington University School of Medicine, Unanue discovered that peptides from foreign antigens were bound to a group of molecules known as the major histocompatibility complex (MHC). This peptide-MHC complex was shown to be recognized by T cells. Although the latter hypothesis was initially greeted with intense skepticism, a large body of work, generated over the last two decades, has confirmed its validity. Education and early career Emil Unanue received his doctorate from the University of Havana (Cuba) in 1960. He then immigrated to the United States and studied briefly at the University of Pittsburgh. Following that experience, Unanue was a postdoctoral research fellow at the Scripps Clinic and Research Foundation, now The Scripps Research Institute in La Jolla, California. With his mentor, Dr. Frank J. Dixon, he made a series of contributions to the field of renal pathophysiology by examining the immune basis of glomerulonephritis. Unanue then joined the group headed by Dr. Brigitte Askonas at the National Institute for Medical Research at Mill Hill in London. Together, Unanue & Askonas made the seminal observation that macrophages did not completely catabolize antigens, foreshadowing development of the field of antigen processing and presentation. In 1970, Unanue was given an appointment in the Department of Pathology at Harvard Medical School, where he