title: Synthetic endotoxin-binding peptides block endotoxin-triggered TNF-alpha production by macrophages in vitro and in vivo and prevent endotoxin-mediated toxic shock.
abstract: Lipid A, the conserved portion of endotoxin, is the major mediator of septic shock; therefore, endotoxin-neutralizing molecules could have important clinical applications. Here we show that peptides derived from Limulus anti-LPS factor (LALF), bactericidal/permeability increasing protein (BPI) and endotoxin-binding protein, bind to lipid A and block the recombinant LALF/lipid A interaction in vitro. Because their neutralizing capacity in vitro as well as in vivo has been limited, we created hybrid peptides comprising two endotoxin-binding domains. The hybrid molecule LL-10-H-14, containing endotoxin-binding domains from LALF and endotoxin-binding protein, turned out to be the most active peptide within the series of peptides tested here to inhibit the CD14/lipid A interaction and is able in vitro to block the endotoxin-induced TNF-alpha release of murine macrophages up to 90%. Furthermore, LL-10-H-14 not only reduced peak serum levels of TNF-alpha of mice when preinjected but also reduced TNF-alpha levels when given 15 min after the endotoxin challenge. As compared with other peptides, only LL-10-H-14 is able to strongly decrease endotoxin-stimulated TNF-alpha release by human macrophage cell lines as well as by PBMC. Furthermore, the hybrid peptide is protective against endotoxin-provoked lethal shock. As such, LL-10-H-14 could have prophylactic and/or therapeutic properties in humans for the management of septic shock.
authors.affiliation: Institute of Medical Microbiology, Immunology and Hygiene, Technical University of Munich, Munich, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Dankesreiter
authors.forename: A
authors.initials: A
authors.lastname: Hoess
authors.forename: J
authors.initials: J
authors.lastname: Schneider-Mergener
authors.forename: H
authors.initials: H
authors.lastname: Wagner
authors.forename: T
authors.initials: T
authors.lastname: Miethke
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides; D060829:Arthropod Proteins; D002460:Cell Line; D004731:Endotoxins / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000633:toxicity*; D005688:Galactosamine / Q000276:immunology; D006737:Horseshoe Crabs / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007447:Invertebrate Hormones / Q000494:pharmacology; D008264:Macrophages / Q000276:immunology* / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology* / Q000378:metabolism* / Q000494:pharmacology; D011485:Protein Binding / Q000276:immunology; D017434:Protein Structure, Tertiary; D012772:Shock, Septic / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D016019:Survival Analysis; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000096:biosynthesis* / Q000378:metabolism
chemical_list: D023181:Antimicrobial Cationic Peptides; D060829:Arthropod Proteins; D004731:Endotoxins; D007166:Immunosuppressive Agents; D007447:Invertebrate Hormones; D008565:Membrane Proteins; D010455:Peptides; D014409:Tumor Necrosis Factor-alpha; C034705:antilipopolysaccharide factor (Limulus); C025357:endotoxin binding proteins; D005688:Galactosamine