A toll on infections

In 1997 the late Charles A. Janeway Jr., M.D., and Ruslan M. Medzhitov, Ph.D., professor of immunobiology, discovered toll-like receptors, or TLRs, molecules that alert the body’s acquired immune system to the presence of microbial or viral invaders.

Scientists have since identified over a dozen types of TLRs, which detect proteins in bacteria and viruses but not those in the eukaryotic cells that make up our bodies. Some pathogens, however, are also eukaryotes, and a team at Yale and the National Institutes of Health wondered whether TLRs could recognize them.

In the June 10 issue of the journal Science, the group reported that TLR11, discovered in mice at Yale last year, triggers an immune response after it detects a protein in the virus that causes toxoplasmosis.

Team member Sankar Ghosh, Ph.D., professor of immunobiology, said that while it is not yet clear whether humans have a functional version of TLR11, these studies should lead to development of novel strategies to combat these infections.