He helped found three important programs: an undergraduate medical school curriculum at his alma mater, the City College of New York, an interdisciplinary Center for Animals and Society at the University of Pennsylvania, and a program in aquatic veterinary medicine (Aquavet) at Penn in conjunction with the Marine Biological Laboratory and other agencies including the Woods Hole Oceanographic Institution, and the National Marine Fisheries Service in Woods Hole, Massachusetts.
Dr. Weiss will be remembered chiefly for his devotion to teaching and mentoring. Dr. Elias Schwartz, a colleague associated with the Children’s Hospital of Philadelphia, describes Weiss as a “medical doctor who successfully taught and pursued research in a prominent school of veterinary medicine and whose most recent interests ranged from malaria, to sickle cell disease, to fish farming.” Dr. Weiss retired from his professorship at the University of Pennsylvania when he was 83 years old, but continued his commitment to malaria research. He discovered what he called a barrier cell in the spleen, which he believed might play an important role in the fight against malaria, a disease that claims millions of lives every year.
To the end, Dr. Weiss continued to visit the library of the Marine Biological Laboratory in Woods Hole, Massachusetts, during the summer months to visit to explore readings on cell biology.
Leon Weiss was born on October 4, 1925 in Brooklyn, New York. His father, Isidor, an immigrant from Hungary, engaged in real estate opportunities during the Depression, while his mother, Florence Reif Weiss, was the daughter of a New York City police lieutenant, also from Hungary. The oldest of three sons who would all become doctors, he graduated from Townsend Harris High School and went on to City College of New York. In 1945, he entered the Long Island College of Medicine and became one of very few Jewish students to be accepted from City College into medical school at a time of quotas on Jewish places. In April 1946, as a second year medical student, Dr. Weiss met his future wife, Ellen Tarter Fishbein, at the Morningside Heights subway stop.
His early teaching career took him to Harvard Medical School where he was an assistant professor in the Department of Anatomy from 1955 to 1960, following service in the Army Medical Corps, at Edgewood Arsenal in Maryland and in Formosa (now Taiwan). While at Harvard he began a long association with the Marine Biological Laboratory. In 1960, he moved to Baltimore to the Johns Hopkins Medical School’s Department of Anatomy. Dr. Weiss’s research specialty was the cells and tissues of the immune system, with emphasis on the hematopoetic organs, or those that create blood. He was editor of the textbook Histology, which is filled with Dr. Weiss’ meticulous drawings and images of cells and tissue structures as seen through the electron microscope. Slides based on these hand illustrations are still used in lectures at the SUNY Downstate Medical School. He was a pioneer in the field of electron microscopy and authored numerous papers on the anatomy of the thymus and spleen.
A quiet introvert, having a lifelong preoccupation with books and writing instruments (chiefly pens and typewriters), Dr. Weiss was a devoted family man, with little interest in travel away from home and work. He is survived by his wife Ellen, an author and artist, and by their six children, Stephen, Philip, Alice, Marisa, Nathaniel and Eve, as well as their spouses, and twelve grandchildren: Adam, Aaron, Elias, Daniel, Ethan, Henry, Isabel, Madeleine, Sara, Ella, Owen, and Livia.
Donations in Dr. Weiss’s memory may be made to the Marine Biological Laboratory in support of the library, care of MBL, 7 MBL Street, Woods Hole, MA 02543.