Anemia and Antibodies to the 19-kDa Fragment of MSP1 During Plasmodium Falciparum Infection in Aotus Monkeys

Comp Med. 2007 Aug;57(4):396-401.


To determine whether antibodies to the 19-kDa fragment of merozoite surface protein 1 (MSP1(19)) help to control blood-stage Plasmodium falciparum infection, we performed a rechallenge experiment of previously infected Aotus monkeys. Monkeys previously exposed to the FVO strain of P. falciparum that did or did not develop high antibody titers to MSP1(19) and malaria-naïve monkeys were challenged with erythrocytes infected with the same strain. Prepatent periods were prolonged in previously infected monkeys compared with malaria-naïve monkeys. Previously infected monkeys with preexisting anti-MSP1(19) antibodies showed low peak parasitemias that cleared spontaneously. Previously infected monkeys that had no or low levels of pre-existing anti-MSP1(19) antibodies also showed low peak parasitemias, but because of low hematocrits, all of these animals required treatment with mefloquine. All previously malaria-naïve animals were treated because of high parasitemias. The results of this study suggest that antibody to the 19-kDa carboxy-terminal fragment of MSP1 plays a role in preventing the development of anemia, an important complication often associated with malaria.

Publication types

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

MeSH terms

  • Anemia / immunology*
  • Anemia / parasitology
  • Anemia / pathology
  • Animals
  • Antibodies, Protozoan / blood
  • Antibodies, Protozoan / immunology*
  • Antimalarials / therapeutic use
  • Aotidae
  • Disease Models, Animal
  • Erythrocytes / parasitology
  • Malaria, Falciparum / complications
  • Malaria, Falciparum / immunology*
  • Malaria, Falciparum / pathology
  • Mefloquine / therapeutic use
  • Merozoite Surface Protein 1 / administration & dosage
  • Merozoite Surface Protein 1 / immunology*
  • Monkey Diseases / immunology
  • Monkey Diseases / parasitology*
  • Monkey Diseases / pathology
  • Parasitemia / drug therapy
  • Parasitemia / immunology
  • Plasmodium falciparum / growth & development
  • Plasmodium falciparum / immunology*


  • Antibodies, Protozoan
  • Antimalarials
  • Merozoite Surface Protein 1
  • Mefloquine