Inactivation of C5a anaphylatoxin by a peptide that is complementary to a region of C5a

J Immunol. 2004 May 15;172(10):6382-7. doi: 10.4049/jimmunol.172.10.6382.

Abstract

PL37 (RAARISLGPRCIKAFTE) is an antisense homology box peptide composed of aa 37-53 of C5a-anaphylatoxin and is considered to be the region essential for C5a function. Using a computer program, we designed the complementary peptides ASGAPAPGPAGPLRPMF (Pep-A) and ASTAPARAGLPRLPKFF (Pep-B). Pep-A bound to PL37 and to C5a with very slow dissociation as determined by analysis using surface plasmon resonance, whereas Pep-B failed to bind at all. C5a was inactivated by concentrations of 7 nM or more of Pep-A, and this concentration of Pep-A inhibited induction of intracellular Ca(2+) influx in neutrophils. Patch clamp electrophysiology experiments also showed the effectiveness of Pep-A in C5aR-expressing neuroblastoma cells. Furthermore, Pep-A administration prevented rats from C5a-mediated rapid lethal shock induced by an Ab to a membrane inhibitor of complement after LPS sensitization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Anaphylaxis / mortality
  • Anaphylaxis / prevention & control
  • Animals
  • Antigens / chemistry
  • Antigens / metabolism
  • Antigens / physiology
  • Antisense Elements (Genetics) / chemical synthesis
  • Antisense Elements (Genetics) / metabolism
  • Antisense Elements (Genetics) / physiology
  • Calcium / metabolism
  • Cell Line, Tumor
  • Cell Separation
  • Complement C5a / antagonists & inhibitors*
  • Complement C5a / metabolism*
  • Complement C5a / physiology
  • Complement Inactivator Proteins / chemical synthesis
  • Complement Inactivator Proteins / metabolism
  • Complement Inactivator Proteins / physiology*
  • Disease Models, Animal
  • Humans
  • Intracellular Fluid / metabolism
  • Male
  • Molecular Sequence Data
  • Neutrophils / immunology
  • Neutrophils / metabolism
  • Patch-Clamp Techniques
  • Peptide Fragments / chemical synthesis
  • Peptide Fragments / metabolism
  • Peptide Fragments / physiology*
  • Protein Binding / immunology
  • Rats
  • Rats, Wistar

Substances

  • Antigens
  • Antisense Elements (Genetics)
  • Complement Inactivator Proteins
  • Peptide Fragments
  • Complement C5a
  • Calcium