Clyde F. Barker, a former professor in the department of surgery in Penn’s School of Medicine, died on October 2 from congestive heart failure. He was 93.

Born in 1932 in Salt Lake City, Utah, Dr. Barker was the youngest of four brothers. After his father died when he was young, Dr. Barker’s older brothers pooled their money to send him to Phillips Exeter Academy in New Hampshire, then to Cornell University, where he graduated with a BA in 1954. Dr. Barker then attended what is today the Weill Medical College at Cornell University, earning his MD in 1958. The same year, he began general surgery training at Penn, and remained at Penn for the remainder of his career. After completing his fellowship in vascular surgery, he joined the faculty of Penn’s School of Medicine. He rose through the ranks to become Penn’s head of transplantation in 1966, an assistant professor in 1968, an associate professor in 1969, a full professor in 1973, and chief of vascular surgery in 1981. During his time at Penn, Dr. Barker held multiple endowed professorships. In 1978, he became the J. William White Professor of Surgical Research in the school, and from 1983 to 2001, he was the John Rhea Barton Professor. After 2001, he became the Donald Guthrie Professor of Surgery. During his time at Penn, he held many other leadership roles, including as chair of clinical practices at the Hospital of the University of Pennsylvania.

Through his work, research, faculty recruitment, and graduate student mentoring, Dr. Barker led Penn to become a national leader in transplantation clinical care and research. Soon after joining Penn, he began work on the immune aspects of tolerance with the pioneer immunologist Rupert Billingham, with whom he co-authored twelve pivotal papers. On February 10, 1966, Dr. Barker put his theories into practice when he implanted a living-donor kidney into recipient Howard Mehl, the first time this procedure was successful. He continued to perform complex and innovative procedures throughout his career at Penn, and went on to found Penn’s division of transplant surgery. Dr. Barker also coauthored with Ali Naji two papers in Science that demonstrated the importance of autoimmunity in the destruction of pancreas islets in diabetes and that intrathymic injection induced tolerance to islet allografts. These papers were part of a body of work that included over 400 peer-reviewed articles; Dr. Barker also served on numerous editorial boards, including that of the Annals of Surgery; was continuously funded by the NIH for 25 years; and earned five R01 grants and an NIH Merit Award.

Outside of Penn, Dr. Barker served as president of the American Surgical Association, the American Society of Transplant Surgeons, the Halsted Society, the International Surgical Group, the Philadelphia Academy of Surgeons, and the American Philosophical Society (the oldest learned society in the U.S., founded by Benjamin Franklin in 1743). He also served on the Board of Governors of the American College of Surgeons and chaired the board of the William Maul Measey Foundation. His work was extensively recognized by his colleagues, who awarded him a Markle Scholarship, the Medallion for Scientific Achievement from the American Surgical Association, the Thomas Starzl Prize in Surgery and Immunology, and the Lifetime Achievement Award from the Society of University Surgeons. Dr. Barker was an elected member of the Institute of Medicine and the American Academy of Arts and Sciences. In his honor, Penn opened the Clyde F. Barker Transplant House as a home away from home for families of patients (Almanac December 16, 2008).

Dr. Barker was a “surgeon, innovator, scientist, leader, administrator, counselor, husband, father, athlete, historian, and friend,” said Perelman School of Medicine Dean Jonathan Epstein. “The term ‘giant’ is often applied to individuals who make important contributions to medicine or medical education. That label seems insufficient to describe Dr. Barker. Rather, he was a titan. He had a distinguished career and an extraordinary life. He has indelibly shaped our department and Penn Medicine.” In 2024, Dr. Barker and his daughter Elizabeth published Surgeons and Something More: The History of Surgery at the University of Pennsylvania, an insightful, witty, and sometimes critical history of his department. 

Dr. Barker is survived by his children, Fred, John, William, and Elizabeth; and six grandchildren.

Contributions can be sent to the Clyde F. Barker Transplant House at Penn Medicine. Credit card donations can be made at http://givingpages.upenn.edu/ClydeBarker. Checks payable to “Trustees of the University of Pennsylvania,” with the note “in memory of Dr. Clyde F. Barker,” should be mailed to Penn Medicine Development, Attn: Andrew Deal, 3535 Market St., Ste. 750, Philadelphia, PA 19104.