Pioneering physician-scientist, nephrologist, and mentor, Dr. M. Amin Arnaout (BS '70, MD '74) has made groundbreaking discoveries that have fundamentally changed the fields of immunology, structural biology, and nephrology. His seminal research on how cells adhere and communicate has led to new and safer therapies for a wide range of diseases.
Born in Saida, Lebanon, Arnaout received both his BS in general studies (1970) and his medical degree with distinction (1974) from the American University of Beirut (AUB). He served on the medical staff of the AUB Medical Center as an intern and resident in medicine before moving to Johns Hopkins University, Baltimore, where he completed his fellowship in nephrology in 1976. He subsequently pursued a postdoctoral fellowship in immunology at the Boston Children's Hospital (1976-78) and in clinical nephrology at Boston Children's Hospital and Brigham and Women's Hospital (1979-80), both affiliated with Harvard Medical School.
Dr. Arnaout is a professor of medicine at Harvard Medical School and principal investigator of the Harvard Stem Cell Institute. At Massachusetts General Hospital, he is director of the Leukocyte Biology and Inflammation Laboratory and the Structural Biology Program, as well as physician and chief emeritus of the Division of Nephrology and head of the Arnaout Laboratory.
His primary research is in the discovery of leukocyte integrins, transmembrane receptor proteins that act as cellular bridges responsible for cell adhesion, survival, and communication. In a lead article in the New England Journal of Medicine, he described an inherited deficiency in leukocyte adhesion manifested by life-threatening bacterial infections and traced it to a deficiency in a family of leukocyte surface glycoprotein receptors—now known as leukocyte β2 integrins—thereby elucidating the role of the integrins in the immune system.
Arnaout's discoveries have advanced the field and changed scientific approaches to treatment and disease understanding. His studies of integrins have been instrumental in understanding the processes of organ development, organ architecture maintenance, and homeostasis in adults, cancer growth and metastasis, and the response of organs to inflammatory or autoimmune injury.
His research further aims at using structure-based drug design to develop novel, effective, and safe treatments for inflammatory, thrombotic, fibrotic, autoimmune diseases, and cancer.
His work has been featured in several renowned journals, and his two research papers published in Science are the most cited in the integrin field for the past 20 years.
Arnaout was elected to the US National Academy of Sciences in 2025. He is the recipient of numerous awards and recognitions, including the Visionary Award in Nephrology from the National Kidney Foundation in 2023; the American Society of Nephrology's 2018 Homer W. Smith Award, which recognized him as one of the major intellectual forces in renal physiology; the Kuwait Prize in Applied Medical Sciences from the Kuwait Foundation for the Advancement of Sciences in 2017; in addition to other recognitions such as the American Society of Nephrology's President's Medal, the National Institutes of Health Young Investigator Award, and the American Heart Association's Established Investigator Award for cardiovascular research.
In 2022, he established an endowed award, the Dr. M. Amin Arnaout Award in Medicine, to recognize outstanding and dedicated medical graduates at his alma mater, AUB. He also served as a leading member of the International Advisory Committee of AUB's Faculty of Medicine (2008-2013).
M. Amin Arnaout is married to Amal Kawwa (BS Pharmacy '75), and together they have two children: Ramy and Rima, both physician-scientists at Harvard and the University of California San Francisco, respectively.