Cytokine and antibody responses to Plasmodium falciparum in naïve individuals during a first malaria episode: effect of age and malaria exposure

PLoS One. 2013;8(2):e55756. doi: 10.1371/journal.pone.0055756. Epub 2013 Feb 21.

Abstract

Age- and exposure-dependent immune responses during a malaria episode may be key to understanding the role of these factors in the acquisition of immunity to malaria. Plasma/serum samples collected from naïve Mozambican children (n=48), European adults (naïve travelers, n=22; expatriates with few prior malaria exposures, n=15) and Mozambican adults with long-life malaria exposure (n=99) during and after a malaria episode were analyzed for IgG against merozoite proteins by Luminex and against infected erythrocytes by flow cytometry. Cytokines and chemokines were analyzed in plasmas/sera by suspension array technology. No differences were detected between children and adults with a primary infection, with the exception of higher IgG levels against 3D7 MSP-1(42) (P=0.030) and a P. falciparum isolate (P=0.002), as well as higher IL-12 (P=0.020) in children compared to other groups. Compared to malaria-exposed adults, children, travelers and expatriates had higher concentrations of IFN-γ (P ≤ 0.0090), IL-2 (P ≤ 0.0379) and IL-8 (P ≤ 0.0233). Children also had higher IL-12 (P=0.0001), IL-4 (P=0.003), IL-1β (P=0.024) and TNF (P=0.006) levels compared to malaria-exposed adults. Although IL-12 was elevated in children, overall the data do not support a role of age in immune responses to a first malaria episode. A T(H)1/pro-inflammatory response was the hallmark of non-immune subjects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Factors
  • Antibody Formation / immunology*
  • Chemokines / blood
  • Child
  • Cytokines / blood*
  • Cytokines / immunology
  • Female
  • Humans
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology
  • Infant
  • Malaria, Falciparum / blood*
  • Malaria, Falciparum / immunology*
  • Malaria, Falciparum / parasitology
  • Male
  • Plasmodium falciparum / immunology*
  • Recombinant Proteins / metabolism
  • Seroepidemiologic Studies

Substances

  • Chemokines
  • Cytokines
  • Immunoglobulin G
  • Recombinant Proteins

Grants and funding

The study received financial support from the Ministerio de Ciencia e Innovación (SAF2008-00743, SAF2005-25642-E, salary support RYC-2008-02631 to CD); the Instituto de Salud Carlos III (PI050275, A107190024, PS0901113, salary support CD10/00156 to GM, CP-4/00220 to AM, and CM04/00028 to CG), the EU FP6 (LSHP-CT-2005-18902), and the Fundación Ramón Areces. The Centro de Investigação em Saúde de Manhiça receives core support from the Spanish Agency for International Cooperation and Development (AECID). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.