Receptor-based identification of an inhibitory peptide against blood stage malaria

Biochem Biophys Res Commun. 2008 Nov 21;376(3):489-93. doi: 10.1016/j.bbrc.2008.09.011. Epub 2008 Sep 13.

Abstract

Plasmodium falciparum uses multiple host receptors to attach and invade human erythrocytes. Glycophorins have been implicated as receptors for parasite invasion in human erythrocytes. Here, we screened a phage display cDNA library of P. falciparum (FCR3, a sialic acid-dependent strain) using purified glycophorins and erythrocytes as bait. Several phage clones were identified that bound to immobilized glycophorins and contained the same 74 bp insert encoding the 7-amino acids sequence ETTLKSF. A similar screen using intact human erythrocytes in solution identified additional phage clones containing the same 7-amino acids sequence. Using ELISA and immunofluorescence, direct binding of ETTLKSF peptide to glycophorins and erythrocytes was confirmed. Pull-down and protease treatment assays suggest that ETTLKSF peptide specifically interacts with glycophorin C. The synthetic ETTLKSF peptide partially blocks merozoite invasion in human erythrocytes. Further characterization of ETTLKSF peptide could lead to the development of a novel class of inhibitors against the blood stage malaria.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antimalarials / chemistry
  • Antimalarials / isolation & purification
  • Antimalarials / pharmacology*
  • Cells, Cultured
  • Erythrocytes / parasitology
  • Glycophorins / chemistry
  • Humans
  • Malaria, Falciparum / blood
  • Malaria, Falciparum / parasitology*
  • Oligopeptides / chemistry
  • Oligopeptides / genetics
  • Oligopeptides / isolation & purification
  • Oligopeptides / pharmacology*
  • Peptide Library
  • Plasmodium falciparum / drug effects*
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics
  • Protozoan Proteins / isolation & purification
  • Protozoan Proteins / pharmacology*

Substances

  • Antimalarials
  • Glycophorins
  • Oligopeptides
  • Peptide Library
  • Protozoan Proteins
  • glutamyl-threonyl-threonyl-leucyl-lysyl-seryl-phenylalanine