Sibley recognized for research
on Toxoplasma gondii

Published April 03 2017

L. David Sibley

“I have known and admired Alice and C.C. Wang for their many contributions to the field of molecular parasitology over many years, and it is a real honor to be nominated for this award by my colleagues. I am humbled to be chosen among so many excellent candidates.”


L. David Sibley, the Alan A. & Edith L. Wolff distinguished professor of molecular microbiology at Washington University School of Medicine in St. Louis, won the American Society of Biochemistry and Microbiology’s Alice and C.C. Wang Award in Molecular Parasitology. Sibley is recognized for his work on mechanisms that help a pathogen adapt inside cells.

The Alice and C.C. Wang award recognizes scientists who have made seminal contributions to the field of molecular parasitology through novel and significant discoveries. The award honors the legacy of the renowned parasitologists C.C. and Alice Wang.

Sibley’s group investigates the intracellular parasite Toxoplasma gondii. A common parasite associated with HIV, T. gondii is capable of infecting almost all warm-blooded animals, but is especially harmful to those with compromised immune systems. To most people, it is best known as the organism that causes toxoplasmosis, a condition that can be contracted through ingestion of oocysts shed by cats or consumption of undercooked meat harboring tissue cysts.

Sibley’s achievements include elucidating how the organism invades the host and achieves virulence by outwitting the cellular pathways of the host cell. Sibley’s work led to development of classical genetic maps for the parasite in order to dissect the genetic footprint and the molecular mechanism of its virulence. His work has advanced our understanding of processes such as cell motility and protein secretion and how these processes are regulated during host invasion by the parasite.

Not only has Sibley’s research established T. gondii as a model system for molecular parasitology, but his work also has set a paradigm for understanding the biology of other pathogens, such as the malarial parasite.

Boris Striepen at the University of Georgia, wrote in his letter of support for Sibley’s nomination, “David began these studies at a time when T. gondii was far from being a model system, in fact it was a rather obscure pathogen, studied by a handful of investigators around the world — he has maintained his position at the very cutting edge of that question for more than thirty years.”

Sibley earned his doctorate at Louisiana State University, where he studied macrophage interactions with T. gondii. During his postdoctoral stint at Stanford University, he discovered that common strains consist of three abundant genotypes. After moving to his current institution, Sibley continued his work on T. gondii.

“It is his completely fearless approach, scientific excellence and rigor that has allowed David to use his expertise in molecular parasitology to cross disciplines and provide novel insights that are broadly relevant to understanding the outcome of host-pathogen interactions,” said Christopher A. Hunter at the University of Pennsylvania’s School of Veterinary Medicine, in his letter supporting Sibley’s nomination.

Sibley is a recipient of the Burroughs–Wellcome Award in Molecular Parasitology, the Molecular, Cellular and Immunoparasitology Scientific Excellence Award from the American Society for Tropical Medicine and Hygiene and the Distinguished Investigator Award from Washington University School of Medicine.

“Sibley is an outstanding scientist regardless how he is measured, or who he is measured against,” wrote Striepen. “He is one of the brightest stars of molecular parasitology and his accomplishments make him a natural candidate for the letter and spirit of the Alice and C.C. Wang Award.”

Sibley’s award lecture will take place during the 2017 ASBMB Annual Meeting in Chicago at 2:30 p.m. April 24 in W184a in McCormick Place.

Aditi Dubey Aditi Dubey is a postdoctoral associate at New York University.