L. David Sibley is the Alan A. and Edith L. Wolff Distinguished Professor in Molecular Microbiology at Washington University School of Medicine, St. Louis. Sibley is a recognized for his work on the cellular and molecular basis of intracellular parasitism and for defining the molecular determinants of pathogenesis that underlie diseases caused by protozoan parasites. Sibley was born in Philadelphia and grew up in Pennsylvania and Ohio. He earned a B.A. degree in biological sciences from Oberlin College in 1978, and a Ph.D. in zoology and physiology from Louisiana State University in 1985. He completed postdoctoral fellowships at the U.S. Public Health Service’s National Hansen’s Disease Center and Stanford University School of Medicine. In 1991, Sibley joined the faculty in the Department of Molecular Microbiology at Washington University School of Medicine, St. Louis. He is a Burroughs-Wellcome Scholar in Molecular Parasitology (2000-2005), a recipient of the Alice and CC Wang Molecular Parasitology Award from the American Society of Biochemistry and Molecular Biology (2017), and a Fellow in the American Academy of Microbiology (2007).

Research Interests

My research program is focused on defining adaptations that enable intracellular parasites to gain entry into their host cells, avoid host defenses, and establish a replicative niche. Using Toxoplasma gondii as a model system, we have defined parasite-mediated mechanisms that control host-cell entry and egress, and that mediate tissue migration during parasite dissemination in the host. Together with an extensive group of international collaborators, we have explored genetic diversity and defined the global population structure of this widespread parasite of warm-blooded vertebrates including humans. We have developed a variety of genetic strategies to compare phenotypic differences between natural isolates and to define the molecular basis of pathogenesis. These studies demonstrate that pathogenesis determinants act by altering host gene expression, blocking signaling pathways, and subverting immune responses. Our findings have uncovered novel and essential aspects of parasite biology that provide opportunities for developing new therapies for animal and human diseases.

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Primary Section

Section 61: Animal, Nutritional, and Applied Microbial Sciences

Secondary Section

Section 44: Microbial Biology