Protection of Aotus Monkeys by Plasmodium Falciparum EBA-175 Region II DNA Prime-Protein Boost Immunization Regimen

J Infect Dis. 2001 Jan 15;183(2):303-312. doi: 10.1086/317933. Epub 2000 Dec 8.

Abstract

Aotus monkeys received 4 doses of Plasmodium falciparum EBA-175 region II vaccine as plasmid DNA (Dv-Dv) or recombinant protein in adjuvant (Pv-Pv) or as 3 doses of DNA and 1 dose of protein (Dv-Pv). After 3 doses, antibody titers were approximately 10(4) in DNA-immunized monkeys and 10(6) in protein-immunized monkeys. A fourth dose did not significantly boost antibody responses in the Dv-Dv only or Pv-Pv only groups, but titers were boosted to approximately 10(6) in monkeys in the Dv-Pv group. Four weeks after the last immunization, the animals were challenged with 10(4) P. falciparum-parasitized erythrocytes. Peak levels of parasitemia were lower in the 16 monkeys that received region II-containing plasmids or proteins than in the 16 controls (geometric mean: 194,178 and 410,110 parasites/microL, respectively; P=.013, Student's t test). Three of 4 monkeys in the Dv-Pv group did not require treatment. These data demonstrate that immunization with EBA-175 region II induces a significant antiparasite effect in vivo.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adjuvants, Immunologic
  • Anemia
  • Animals
  • Antibodies, Protozoan / blood
  • Antigens, Protozoan*
  • Aotus trivirgatus
  • Carrier Proteins / administration & dosage
  • Carrier Proteins / genetics
  • Carrier Proteins / immunology*
  • Disease Models, Animal
  • Female
  • Humans
  • Immunization Schedule
  • Immunization, Secondary
  • Malaria Vaccines / administration & dosage
  • Malaria Vaccines / immunology*
  • Malaria, Falciparum / parasitology
  • Malaria, Falciparum / prevention & control*
  • Male
  • Parasitemia / parasitology
  • Plasmodium falciparum / immunology*
  • Protozoan Proteins / administration & dosage
  • Protozoan Proteins / genetics
  • Protozoan Proteins / immunology*
  • Vaccination
  • Vaccines, DNA / immunology*
  • Vaccines, Synthetic / immunology

Substances

  • Adjuvants, Immunologic
  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Carrier Proteins
  • Malaria Vaccines
  • Protozoan Proteins
  • Vaccines, DNA
  • Vaccines, Synthetic
  • erythrocyte-binding antigen 175, Plasmodium