Synthetic endotoxin-binding peptides block endotoxin-triggered TNF-alpha production by macrophages in vitro and in vivo and prevent endotoxin-mediated toxic shock

J Immunol. 2000 May 1;164(9):4804-11. doi: 10.4049/jimmunol.164.9.4804.


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.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antimicrobial Cationic Peptides
  • Arthropod Proteins
  • Cell Line
  • Endotoxins / antagonists & inhibitors
  • Endotoxins / metabolism
  • Endotoxins / toxicity*
  • Galactosamine / immunology
  • Horseshoe Crabs / immunology
  • Humans
  • Immunosuppressive Agents / pharmacology
  • Invertebrate Hormones / pharmacology
  • Macrophages / immunology*
  • Macrophages / metabolism
  • Male
  • Membrane Proteins / metabolism
  • Membrane Proteins / pharmacology*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Peptides / chemical synthesis
  • Peptides / immunology*
  • Peptides / metabolism*
  • Peptides / pharmacology
  • Protein Binding / immunology
  • Protein Structure, Tertiary
  • Shock, Septic / immunology
  • Shock, Septic / mortality
  • Shock, Septic / prevention & control*
  • Survival Analysis
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors*
  • Tumor Necrosis Factor-alpha / biosynthesis*
  • Tumor Necrosis Factor-alpha / metabolism


  • Antimicrobial Cationic Peptides
  • Arthropod Proteins
  • Endotoxins
  • Immunosuppressive Agents
  • Invertebrate Hormones
  • Membrane Proteins
  • Peptides
  • Tumor Necrosis Factor-alpha
  • antilipopolysaccharide factor (Limulus)
  • endotoxin binding proteins
  • Galactosamine