Seymour S. Cohen, a Nobel Prize-nominated research scientist and the first chairman of the department of therapeutic research in Penn’s School of Medicine, died December 30. He was 101.

Dr. Cohen was born in New York City. He received his BS from the City College of New York in 1936 and his PhD in biochemistry from Columbia University in 1941.

During World War II he worked with the US Army to develop an improved typhus vaccine that was an important aid to US troops in Italy and North Africa. He worked at the Rockefeller Institute in Princeton in 1942.

Dr. Cohen came to the department of pediatrics of the University of Pennsylvania and Children’s Hospital in Philadelphia in 1943. He later moved to Penn’s School of Medicine, where in 1963 he was named the first chairman of the department of therapeutic research and the Hartzell Professor in Therapeutic Research.

Dr. Cohen’s work was deep and broad. In 1947, he discovered how viral infection spread within cells by linking a radioactive isotope to a virus and observing the pattern of infection within cells. He also worked extensively on the biochemistry of bacteriophages and patterns of growth in plants.

He received numerous awards, including the Eli Lilly Prize for his work on virus and cells and the American Society for Nutrition’s Mead Johnson Award. In 1957 he was named as the first Lifetime Professor of the American Cancer Society for his role in the development of new compounds to fight cancer. Dr. Cohen was elected to the American Academy of Arts and Sciences and the US National Academy of Sciences (NAS).

He was nominated several times for the Nobel Prize and is therefore included among the group of people who hold the “Forty-First Chair” (scientists deemed worthy candidates for the Nobel Prize by the Nobel committee).

In 1970, Dr. Cohen moved to the University of Colorado Medical School in Denver as a professor of microbiology. Five years later, he was named the Albert Schweitzer Distinguished Professor at the State University of New York at Stony Brook.

Dr. Cohen’s scientific papers, including more than 250 publications, are held in the Seymour S. Cohen Papers, 1938-1990, at the Library of the American Philosophical Society (APS) in Philadelphia. He also donated his extensive library about Thomas Cooper, an English polymath and political activist who emigrated to the US in 1794, to the APS.

Dr. Cohen is survived by his children, Michael A. (Margarita Gutman) and Sara E. Cohen (James M. Kessler); five grandchildren; five great-grandchildren; and extended family. A celebration of Dr. Cohen’s life will be held in Woods Hole, Massachusetts, during the summer.