Innate immune system pattern-recognition pathways (PRR pathways) (PRR pathways)

The innate immune system pattern-recognition pathways are a fundamental set of signaling cascades used by the host to detect and respond to pathogens and cellular damage (NIH, 2025). These pathways are initiated by Pattern Recognition Receptors (PRRs), which include Toll-like receptors (TLRs), NOD-like receptors (NLRs), RIG-I-like receptors (RLRs), C-type lectin receptors (CLRs), and cytosolic DNA sensors like the cGAS-STING pathway (Wikipedia, 2025; NIH, 2025). Upon binding to pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs), these receptors trigger downstream signaling through adaptors like MyD88, TRIF, MAVS, or STING (NIH, 2025). This signaling culminates in the activation of transcription factors such as NF-κB and Interferon Regulatory Factors (IRFs), leading to the production of pro-inflammatory cytokines, chemokines, and type I interferons (MDPI, 2025). These molecules orchestrate the initial immune defense and are crucial for priming the adaptive immune system (NIH, 2025). Dysregulation of these pathways is implicated in various diseases, including chronic inflammatory conditions, autoimmune disorders, and sepsis (NIH, 2025). In oncology, agonists of these pathways are being developed to stimulate anti-tumor immunity and enhance the efficacy of vaccines (ResearchGate, 2021). Conversely, antagonists and inhibitors are explored as treatments for autoinflammatory diseases where excessive PRR signaling drives pathology (NIH, 2025). The therapeutic potential of targeting these pathways is vast, though challenges such as systemic toxicity and cytokine release syndrome must be managed (NIH, 2025).

Other names

Pattern recognition receptor pathwaysPRR signaling pathwaysInnate immune sensing pathwaysInnate immune pathways

Agonism of pattern recognition receptors to stimulate innate and adaptive immune responses, or antagonism/inhibition of these pathways to suppress pathological inflammation.