Joseph Frederick Hoffman, PhD, Eugene Higgins Emeritus Professor of Cellular and Molecular Physiology, died May 19, 2022 at the age of 97. He was a tireless and dedicated red blood cell researcher who published papers until the age of 93.
Hoffman was born March 7, 1925, in Oklahoma City, Oklahoma, where, like his two older brothers, he attained the rank of Eagle Scout. He graduated from the University of Oklahoma in 1948 after earning bachelor’s and master’s degrees. He was then admitted to the graduate school of Princeton University where he obtained a second master’s degree (1951) and a doctorate in physiology (1952). After graduating, he joined the faculty of the Department of Biology at Princeton and conducted studies at the Brookhaven National Laboratory.
He left Princeton in 1956 to pursue research at the University of Cambridge, and in 1957 he was hired by Robert Berliner (future Dean of the Yale School of Medicine) who then held the position of Director of the Renal Metabolism Laboratory. and electrolytics at the National Institutes of Health. Hoffman came to Yale in 1965 to join the faculty of the Department of Physiology, serving as department chairman from 1967 to 1968 and from 1973 to 1979.
While at Princeton, Hoffman began his studies of the membrane permeability properties of red blood cells, which became his central focus for more than six decades of research. He was intrigued by the roles of ion pumps and ATP-driven ion channels in defining the ion composition of a cell’s cytoplasm and in regulating cell volume. During his time at Brookhaven, Hoffman met and formed a lifelong friendship with Daniel Tosteson (who later served as dean of Harvard Medical School). Hoffman and Tosteson became close scientific collaborators and in 1960 published a landmark article in the Journal of General Physiology who described their “pump-leak” model. This mathematical formulation provided a theoretical framework that explained in predictive detail how flows through ion pumps, channels, and transporters explain ion distributions across a cell’s plasma membrane and the maintenance of A stable cell volume despite osmotic forces that might be expected to produce cell swelling and lysis.
While at Yale, Hoffman continued to explore membrane transport mechanisms and their role in cell shape determination. Hoffman and his colleagues created very versatile light-activated chemical probes that could be used to label ion transport proteins and to study the kinetic properties of ion transport processes. Although he officially closed his laboratory and became professor emeritus in 2003, he remained passionately involved in the biology of red blood cells. His last two research papers, which explored the mechanisms by which red blood cells retain their intriguing biconcave disc shape, were published in the Proceedings of the National Academy of Sciences in 2016 and 2018, when he was 91 and 93 years old. For his many accomplishments as a scientist and as a leader, Hoffman received numerous accolades, including election to the National Academy of Sciences in 1981 and the American Academy of Arts and Sciences in 1984. He has served as president of the Biophysical Society and the Society of General Physiologists, and has edited numerous books and journals. Hoffman was very active in the intellectual life and community spirit of the Department of Cellular and Molecular Physiology until he fell ill in early April of this year.
Hoffman’s survivors include his nephew, Richard E. Hoffman, MD (Molly), of Denver, CO; his nieces, Patricia Ann McNichols of Milwaukee, WI, Jill E. Tiernan (Thomas) of Dallas, TX, and Claudia Citkovitz (John Barnard) of Shutesbury, MA; his sister-in-law, Evgenia Citkowitz; and six great-nieces, as well as cousins and in-laws. He was predeceased by Elena Citkowitz, MD (Yale ’83), his wife of 41 years, and his two brothers, Edmund Hoffman and Henry Hoffman Jr.