Antibodies to full-length and the DBL5 domain of VAR2CSA in pregnant women after long-term implementation of intermittent preventive treatment in Etoudi, Cameroon

PLoS One. 2020 Aug 14;15(8):e0237671. doi: 10.1371/journal.pone.0237671. eCollection 2020.

Abstract

In high malaria transmission settings, the use of sulfadoxine-pyrimethamine-based intermittent preventive treatment during pregnancy (IPTp-SP) has resulted in decreased antibody (Ab) levels to VAR2CSA. However, information of Ab levels in areas of low or intermediate malaria transmission after long-term implementation of IPTp-SP is still lacking. The present study sought to evaluate antibody prevalence and levels in women at delivery in Etoudi, a peri-urban area in the capital of Yaoundé, Cameroon, that is a relatively low-malaria transmission area. Peripheral plasma samples from 130 pregnant women were collected at delivery and tested for IgG to the full-length recombinant VAR2CSA (FV2) and its most immunogenic subdomain, DBL5. The study was conducted between 2013 and 2015, approximately ten years after implementation of IPTp-SP in Cameroon. About 8.6% of the women attending the clinic had placental malaria (PM). One, two or 3 doses of SP did not impact significantly on either the percentage of women with Ab to FV2 and DBL5 or Ab levels in Ab-positive women compared to women not taking SP. The prevalence of Ab to FV2 and DBL5 was only 36.9% and 36.1%, respectively. Surprisingly, among women who had PM at delivery, only 61.5% and 57.7% had Ab to FV2 and DBL5, respectively, with only 52.9% and 47.1% in PM-positive paucigravidae and 77.7% of multigravidae having Ab to both antigens. These results suggest that long-term implementation of IPTp-SP in a low-malaria transmission area results in few women having Ab to VAR2CSA.

Publication types

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

MeSH terms

  • Adult
  • Antibodies, Protozoan / blood
  • Antibodies, Protozoan / immunology*
  • Antigens, Protozoan / immunology*
  • Antimalarials / therapeutic use*
  • Cameroon / epidemiology
  • Drug Combinations
  • Female
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Malaria / blood
  • Malaria / epidemiology
  • Malaria / immunology
  • Malaria / prevention & control
  • Malaria, Falciparum / blood
  • Malaria, Falciparum / epidemiology
  • Malaria, Falciparum / immunology
  • Malaria, Falciparum / prevention & control*
  • Plasmodium falciparum / drug effects
  • Plasmodium falciparum / immunology
  • Pregnancy
  • Pregnancy Complications, Parasitic / blood
  • Pregnancy Complications, Parasitic / epidemiology
  • Pregnancy Complications, Parasitic / immunology
  • Pregnancy Complications, Parasitic / prevention & control*
  • Pyrimethamine / therapeutic use*
  • Sulfadoxine / therapeutic use*
  • Young Adult

Substances

  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Antimalarials
  • Drug Combinations
  • Immunoglobulin G
  • VAR2CSA protein, Plasmodium falciparum
  • fanasil, pyrimethamine drug combination
  • Sulfadoxine
  • Pyrimethamine

Grants and funding

The World Academy of Sciences (TWAS) received by RM, supported this work; research Grant No: 12-081 RG/BIO/AF: AC_I---UNESCO FR: 3240271366, Faculty of Science, University of Yaoundé I. The Luminex MAGpix was provided by grant P30GM11473, Centers of Biomedical Research Excellence, National Institute of General Medical Sciences, NIH; received by DWT research team. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.