Joseph Fredrik Hoffmann, Ph.D., Eugene Higgins Professor Emeritus of Cellular and Molecular Physiology, died on May 19, 2022 at the age of 97. He was a diligent and dedicated researcher of red blood cells and published research papers until he was 93 years old.
Hoffman was born on March 7, 1925, in Oklahoma City, Oklahoma, where, like his two older brothers, he received the rank of Eagle Scout. He graduated from the University of Oklahoma in 1948 with his bachelor’s and master’s degrees. He was then accepted into Princeton University Graduate School where he earned a second master’s degree (1951) and a doctorate in physiology (1952). After completing his studies, he joined the faculty of the Department of Biology at Princeton and conducted studies at Brookhaven National Laboratory.
He left Princeton in 1956 to pursue research work at the University of Cambridge, and in 1957, he was appointed by Robert Berliner (future Dean of Yale University School of Medicine) who was then director of the Renal and Electrolyte Metabolism Laboratory at the National Institutes of Health. Hoffman came to Yale University in 1965 to join the faculty of the Department of Physiology, serving as department chair 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 have become his focus during more than six decades of research. He was fascinated by the roles of ion pumps and ion channels driven by ATP in determining the ionic composition of the cell’s cytoplasm and in regulating cell size. During his time at Brookhaven, Hoffman met and formed a long-term friendship with Daniel Tostison (who later served as dean of Harvard Medical School). Hoffman and Tostison became close scientific collaborators, and in 1960, they published a landmark research paper in Journal of General Physiology which described the “pump leakage” model. This mathematical formulation provided a theoretical framework that explained in predictive detail how flows through ion pumps, channels, and transporters explain the distribution of ions across the plasma membrane of a cell and to maintain a stable cell volume despite osmotic forces that may be. It is expected to result in cell swelling and lysis.
During his time at Yale University, Hoffman continued to explore the mechanisms of membrane transport and its role in determining cell shape. Hoffman and colleagues have created highly versatile, light-activated chemical probes that can be used to label ion transport proteins and study the kinetic properties of ion transport processes. Although he formally closed his laboratory and became a professor emeritus in 2003, he remained passionately involved in red blood cell biology. The last two research papers have been published in Proceedings of the National Academy of Sciences 2016 and 2018, when he was 91 and 93 years old. For his many accomplishments as a scientist and as a leader, Hoffman has received numerous honors, 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 a very active participant in the intellectual life and community ethos 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, Colorado; His nieces, Patricia Ann McConchols of Milwaukee, Wisconsin, and Jill E. Ternan (Thomas) of Dallas, Texas, and Claudia Sitkowitz (John Barnard) of Shotsbury, Massachusetts; his wife’s sister, Evgenia Sitkovitz; Six are cousins, as well as cousins and in-laws. He died by Elena Sitkowitz, MD (Yale University ’83), his wife of 41 years, and two brothers, Edmund Hoffman and Henry Hoffman Jr.