Toll-like receptors: mammalian "taste receptors" for a smorgasbord of microbial invaders.

In Drosophila, the Toll family of proteins is responsible for the recognition of bacteria and fungi. In mammals, Toll-like receptors (TLRs) are able to recognize and respond to microbial pathogens. Recent findings have defined the relationship between many TLRs and their microbial ligands, as well as the effect of TLR ligation on host defense. These findings have also provided a framework for determining how TLRs may by used to therapeutically modulate immune responses to infection.