IgG antibody responses to Plasmodium falciparum merozoite antigens in Kenyan children have a short half-life

Malar J. 2007 Jun 28;6:82. doi: 10.1186/1475-2875-6-82.

Abstract

Background: Data suggest that antibody responses to malaria parasites merozoite antigens are generally short-lived and this has implications for serological studies and malaria vaccine designs. However, precise data on the kinetics of these responses is lacking.

Methods: IgG1 and IgG3 responses to five recombinant Plasmodium falciparum merozoite antigens (MSP-119, MSP-2 type A and B, AMA-1 ectodomain and EBA-175 region II) among Kenyan children were monitored using ELISA for 12 weeks after an acute episode of malaria and their half-lives estimated using an exponential decay model.

Results: The responses peaked mainly at week 1 and then decayed rapidly to very low levels within 6 weeks. Estimation of the half-lives of 40 IgG1 responses yielded a mean half-life of 9.8 days (95% CI: 7.6-12.0) while for 16 IgG3 responses it was 6.1 days (95% CI: 3.7-8.4), periods that are shorter than those normally described for the catabolic half-life of these antibody subclasses.

Conclusion: This study indicates antibodies against merozoite antigens have very short half-lives and this has to be taken into account when designing serological studies and vaccines based on the antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Protozoan / immunology*
  • Antibody Specificity
  • Antigens, Protozoan / immunology*
  • Child
  • Cohort Studies
  • Enzyme-Linked Immunosorbent Assay
  • Half-Life
  • Humans
  • Immunoglobulin G / immunology*
  • Kenya
  • Longitudinal Studies
  • Malaria, Falciparum / immunology*
  • Merozoites / immunology*
  • Plasmodium falciparum / immunology*

Substances

  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Immunoglobulin G