Innate immune pattern-recognition receptor (PRR) (PRR)

Innate immune pattern-recognition receptors (PRRs) are a diverse class of germline-encoded proteins primarily expressed on antigen-presenting cells (APCs) such as dendritic cells, macrophages, and monocytes (Kawai & Akira, 2010). These receptors are specialized to detect pathogen-associated molecular patterns (PAMPs) from microbes or damage-associated molecular patterns (DAMPs) from injured host cells (Takeuchi & Akira, 2010). Major families include Toll-like receptors (TLRs), NOD-like receptors (NLRs), RIG-I-like receptors (RLRs), and C-type lectin receptors (CLRs) (Li & Wu, 2021). Upon ligand binding, PRRs initiate intracellular signaling pathways, such as the NF-κB or IRF pathways, leading to the secretion of pro-inflammatory cytokines, chemokines, and the upregulation of co-stimulatory molecules (Janeway & Medzhitov, 2002). This process is essential for the activation of the adaptive immune system and the orchestration of an effective immune response. In clinical practice, PRR agonists like imiquimod and monophosphoryl lipid A are utilized as potent vaccine adjuvants and in cancer immunotherapy to stimulate the immune system against pathogens or tumors (Li & Wu, 2021). Conversely, PRR antagonists are being developed to mitigate excessive inflammation in conditions like sepsis and autoimmune disorders (Takeuchi & Akira, 2010).

Other names

Pattern-recognition receptorPRRPathogen recognition receptorInnate immune sensor

Agonism of specific PRR subtypes (e.g., TLRs, NLRs) to induce pro-inflammatory cytokine production and enhance antigen presentation for vaccines and oncology; Antagonism of PRRs to block pathological signaling in autoimmune and autoinflammatory diseases.