Guest, Maurice Mason (1906–1991)

By: Chester R. Burns

Type: Biography

Published: January 1, 1995

Mason Guest, physiologist and medical school professor, was born on July 30, 1906, in Fredonia, New York, the son of Maurice S. and Daisy (Mason) Guest. He earned a bachelor's degree in biology from the University of Michigan (1930) and a doctorate in physiology from Columbia University (1941). In 1930–31 he worked as field assistant for the United States Department of Agriculture Bureau of Entomology. From 1931 to 1936 he was a science teacher at Sherman High School in New York. Guest then worked as instructor of physiology at Columbia University, 1936–40, and as research associate at Columbia, 1940–42. Between 1942 and 1946 he was an aviation physiologist with the United States Army Air Forces and director of the Altitude and Survival Training Program in the Western Flying Training Command.

Guest was a faculty member of the Department of Physiology at Wayne State University College of Medicine for five years before becoming professor and chairman of the Department of Physiology at the University of Texas Medical Branch in 1951. During twenty-two years in this position, he acquired an international reputation for his skills as administrator, professor, and researcher. During the 1950s he and Donald Duncan initiated doctoral programs in anatomy and physiology at UTMB. In 1952 Guest and his colleagues discovered urokinase, an enzyme that dissolves blood clots. They also demonstrated that thrombin, a blood clotting factor, is a proteolytic enzyme. In 1965 the National Institutes of Health awarded Guest and his associates a multimillion-dollar grant to fund their innovative research in hematology and microcirculation.

Guest was a member of several professional societies and published more than 100 scientific studies. He served on committees of the National Research Council and the National Institutes of Health, and he was associate editor for the Journal of Microvascular Research from 1969 to 1972. At the time of his retirement as chairman in 1973, the University of Texas Board of Regents honored Guest with the Ashbel Smith Professorship of Physiology. From then until the time of his death, he served as chief of the Hematology Laboratory at the Shriners Burn Institute in Galveston.

Guest married Alice Rhoda Avery on August 16, 1936, and they had two sons. Guest was an avid gardener, bicyclist, and ceramic artist; he was a founder of the Sierra Club in Galveston. He died in Galveston on June 21, 1991.

Galveston Daily News, June 24, 1991. The University of Texas Medical Branch at Galveston: A Seventy-five Year History (Austin: University of Texas Press, 1967).
  • Education
  • Educators
  • Medical
  • Health and Medicine
  • Founders and Pioneers
  • School Founders

The following, adapted from the Chicago Manual of Style, 15th edition, is the preferred citation for this entry.

Chester R. Burns, “Guest, Maurice Mason,” Handbook of Texas Online, accessed June 26, 2022,

Published by the Texas State Historical Association.

January 1, 1995

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