Invited review: Roles for accessory molecules in microbial recognition by Toll-like receptors

Abstract

The Toll family of receptors recognizes a variety of microbial products and triggers immune responses. Recent progress has revealed a requirement for accessory molecules in microbial recognition by Toll-like receptors. Lipopolysaccharide (LPS) recognition requires LPS binding protein (LBP), CD14, and MD-2. MD-2 is directly involved in ligand-binding and subsequent receptor activation, whereas LBP and CD14 control ligand presentation to the receptor complex, Toll-like receptor (TLR4)/MD-2. CD14 and LBP influence the amplitude of LPS responses and LPS-induced type I interferon production. TLR2 is also reported to require similar accessory molecules. Innate immune responses to microbial products driven by TLRs are controlled by accessory molecules working upstream of TLRs.

Keywords

Toll-like receptors LPS LBP CD14 MD-2

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