Mapping the anatomy of a Plasmodium falciparum MSP-1 epitope using pseudopeptide-induced mono- and polyclonal antibodies and CD and NMR conformation analysis

J Struct Biol. 2004 Oct;148(1):110-22. doi: 10.1016/j.jsb.2004.04.010.

Abstract

Antigen structure modulation represents an approach towards designing subunit malaria vaccines. A specific epitope's alpha carbon stereochemistry, as well as its backbone topochemistry, was assessed for obtaining novel malarial immunogens. A variety of MSP-1(38-61) Plasmodium falciparum epitope pseudopeptides derived were synthesised, based on solid-phase pseudopeptide chemistry strategies; these included all-L, all-D, partially-D substituted, all-Psi-[NH-CO]-Retro, all-Psi-[NH-CO]-Retro-inverso, and Psi-[CH2NH] reduced amide surrogates. We demonstrate that specific recombinant MSP-1(34-469) fragment binding to red blood cells (RBCs) is specifically inhibited by non-modified MSP-1(42-61), as well as by its V52-L53, M51-V52 reduced amide surrogates and partial-D substitutions in K48 and E49. In vivo tests revealed that reduced amide pseudopeptide-immunised Aotus monkeys induced neutralising antibodies specifically recognising the MSP-1 N-terminus region. These findings support the role of molecular conformation in malaria vaccine development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Protozoan / immunology
  • Aotidae
  • Circular Dichroism
  • Epitope Mapping*
  • Erythrocytes / metabolism
  • Immunization
  • Magnetic Resonance Spectroscopy
  • Merozoite Surface Protein 1 / chemistry*
  • Merozoite Surface Protein 1 / genetics
  • Merozoite Surface Protein 1 / immunology
  • Models, Molecular
  • Molecular Sequence Data
  • Peptides / chemical synthesis
  • Peptides / chemistry
  • Peptides / immunology*
  • Plasmodium falciparum / immunology*
  • Plasmodium falciparum / metabolism
  • Protein Conformation

Substances

  • Antibodies, Monoclonal
  • Antibodies, Protozoan
  • Merozoite Surface Protein 1
  • Peptides