Pattern recognition receptor

Pattern recognition receptors, or PRRs, are a class of cell surface receptors which are employed by the cells of the immune system to identify foreign (disease-associated) biomolecules in the body.

PRRs function by binding specifically to small portions of pathogenic molecules, including lipopolysaccharides, peptidoglycans, certain proteins, double-stranded RNA, and a number of others. The specific molecular sequences identified by a given PRR are its PAMPs: pathogen-associated molecular patterns.

The toll-like receptors are a major class of PRRs.