Innate RNA-sensing pattern recognition receptor (RNA-sensing PRR) (RNA-sensing PRR)

Innate RNA-sensing pattern recognition receptors (PRRs) are a specialized class of immune sensors that detect non-self or damaged self-RNA to trigger protective inflammatory responses. These receptors are strategically localized within the cell: Toll-like receptors (TLR3, TLR7, TLR8) monitor the endosomal compartments for internalized viral or bacterial RNA, while RIG-I-like receptors (RIG-I, MDA5) and other sensors like PKR and OAS scan the cytoplasm [PMID: 31003747, PMID: 27695066]. Activation of these pathways typically leads to the recruitment of adaptor proteins such as MAVS or TRIF, ultimately inducing the expression of type I interferons and other pro-inflammatory cytokines that restrict pathogen replication [PMID: 33053329]. In therapeutic contexts, RNA-sensing PRRs are targeted by agonists like imiquimod and poly(I:C) to serve as vaccine adjuvants or anti-cancer immunotherapies by stimulating the innate immune system [PMID: 29343438]. Conversely, dysregulation or chronic activation of these sensors by endogenous RNA is a key driver in the pathogenesis of autoimmune diseases like systemic lupus erythematosus and Aicardi-Goutières syndrome, making them targets for inhibitory drug development [PMID: 30105172].

Other names

RNA PRRsNucleic acid sensorsCytosolic RNA sensorsEndosomal RNA sensorsRNA-sensing receptors

Agonism of endosomal or cytosolic sensors to induce type I interferon and pro-inflammatory cytokine production for antiviral or antitumor activity; antagonism to suppress pathological inflammation in autoimmune diseases.