Immunisation with recombinant AMA-1 protects mice against infection with Plasmodium chabaudi

Vaccine. Jan-Feb 1998;16(2-3):240-7. doi: 10.1016/s0264-410x(97)88331-4.

Abstract

The Plasmodium merozoite surface antigen apical membrane antigen-1 (AMA-1) has previously been shown to provide partial protection to Saimiri and rhesus monkeys immunised with recombinant Plasmodium fragile or parasite-derived Plasmodium knowlesi AMA-1, respectively. In the study reported here we have used the Plasmodium chabaudi/mouse model system to extend our pre-clinical assessment of an AMA-1 vaccine. We describe here the expression of the full-length Plasmodium chabaudi adami AMA-1 and the P. chabaudi adami AMA-1 ectodomain using both baculovirus and Escherichia coli. The ectodomain expressed in E. coli, which contained an N-terminal hexa-his tag, was purified by Ni-chelate chromatography and refolded in vitro in the presence of oxidised and reduced glutathione to generate intramolecular disulphide bonds. In a series of vaccine trials, in both inbred and outbred mice, highly significant protection was obtained by immunising with the refolded AMA-1 ectodomain. Protection was shown to correlate with antibody response and was dependent on intact disulphide bonds. Passive transfer of antibodies raised in rabbits against the refolded AMA-1 ectodomain was also protective. In view of this demonstration that E. coli expression of a soluble P. chabaudi AMA-1 domain can generate a vaccine that is effective in mice, we are pursuing a similar approach to generating a vaccine against P. falciparum for testing in human volunteers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / immunology
  • Antigens, Protozoan*
  • Malaria / immunology
  • Malaria / prevention & control*
  • Malaria Vaccines / administration & dosage*
  • Membrane Proteins / administration & dosage*
  • Membrane Proteins / biosynthesis
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C3H
  • Plasmodium chabaudi / immunology*
  • Protozoan Proteins / administration & dosage*
  • Protozoan Proteins / biosynthesis
  • Recombinant Proteins / administration & dosage

Substances

  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Malaria Vaccines
  • Membrane Proteins
  • Protozoan Proteins
  • Recombinant Proteins
  • apical membrane antigen I, Plasmodium