astrovirus-derived peptide RLS-0071

A 15 amino acid-long peptide derived from the capsid protein of Astrovirus and a small 24-mer polyethylene glycol (PEG) tail on its C-terminus, with potential immunomodulating, anti-inflammatory and complement cascade inhibiting activities. Upon administration, Astrovirus-derived peptide RLS-0071 targets and binds to the hydrophobic pocket of the hinge region of C1q, which is part of the initiating component C1 of the classical complement pathway, thereby blocking and displacing the serine protease enzymatic core complex and preventing C1 cleavage. This inhibits the activation of C1 and the classical complement pathway. This reduces the infiltration of immune cells, thereby reducing complement-mediated inflammation and decreasing complement-mediated hemolysis. In addition, RLS-0071 also binds to and inhibits the initiating component of the lectin complement pathway mannose-binding lectin (MBL). In addition, RLS-0071 inhibits the activity of myeloperoxidase (MPO), thereby preventing the generation of hypochlorous acid by MPO. This modulates neutrophil activation and prevents neutrophil extracellular trap (NET) formation, and the induction of NETosis. This prevents neutrophil-associated and NETosis-induced host tissue damage in many inflammatory processes.