SPA4 Peptide – Immunology – Antigens/Epitotes/Pools/Librairies

SPA4 is a surfactant protein-A (SP-A)-derived peptide which is an antagonist of toll-like receptor-4 (TLR4). SP-A and TLR4 have been identified as important pathogen-pattern recognition receptors (PPRRs). SP-A represents the majority of SPs and plays a key role in fighting pathogens and down-regulating inflammation, whereas TLR4 recognises pathogens and endogenous stress proteins and induces the inflammatory and adaptive immune responses. Over-activation of TLR4 induces inflammatory response via NF-KB and TNF-α cytokine. SPA4 has been shown to bind to TLR4 and inhibit the release of TNF-α in response to the most potent TLR4-ligand: Gram-negative bacteria-derived lipopolysaccharide (LPS), however SPA4 does not interfere with LPS binding to TLR4. The suppression of LPS-TLR4 signalling by SPA4 peptide alleviates inflammatory response.