Toll-Like Receptors and Inflammasomes

Abstract

The recognition of microorganisms is mediated by germline pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs) and nucleotide-binding domain, leucine-rich repeat-containing proteins (NLRs) that interact with conserved structures of the microorganisms, the pathogen-associated molecular patterns (PAMPs). PRRs activate intracellular signals that collaborate for efficient activation of host defense. One such specific collaboration is the interaction between TLRs and cytosolic NLRs. NLRs are the triggering components of the inflammasomes, and the combination of TLR and NLR signaling results in the activation of caspase-1, followed by processing and secretion of the highly proinflammatory cytokines IL-1 beta and IL-18. Understanding the mechanisms of interaction between TLRs and inflammasomes is important, since defects that influence this interaction might lead to autoinflammatory diseases or impaired host defense.