Plasmodium falciparum erythrocyte membrane protein-1 specifically suppresses early production of host interferon-gamma

Cell Host Microbe. 2007 Aug 16;2(2):130-8. doi: 10.1016/j.chom.2007.06.012.

Abstract

Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP-1) is a variable antigen expressed by P. falciparum, the malarial parasite. PfEMP-1, present on the surface of infected host erythrocytes, mediates erythrocyte binding to vascular endothelium, enabling the parasite to avoid splenic clearance. In addition, PfEMP-1 is proposed to regulate host immune responses via interactions with the CD36 receptor on antigen-presenting cells. We investigated the immunoregulatory function of PfEMP-1 by comparing host cell responses to erythrocytes infected with either wild-type parasites or transgenic parasites lacking PfEMP-1. We showed that PfEMP-1 suppresses the production of the cytokine interferon-gamma by human peripheral blood mononuclear cells early after exposure to P. falciparum. Suppression of this rapid proinflammatory response was CD36 independent and specific to interferon-gamma production by gammadelta-T, NK, and alphabeta-T cells. These data demonstrate a parasite strategy for downregulating the proinflammatory interferon-gamma response and further establish transgenic parasites lacking PfEMP-1 as powerful tools for elucidating PfEMP-1 functions.

Publication types

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

MeSH terms

  • Animals
  • Animals, Genetically Modified / immunology*
  • Antigens, Protozoan / genetics
  • Erythrocyte Membrane
  • Host-Parasite Interactions / immunology
  • Humans
  • Immunity, Innate*
  • Interferon-gamma / antagonists & inhibitors*
  • Malaria, Falciparum / immunology*
  • Models, Immunological
  • Plasmodium falciparum / genetics
  • Plasmodium falciparum / immunology*
  • Plasmodium falciparum / pathogenicity
  • Protozoan Proteins / genetics*

Substances

  • Antigens, Protozoan
  • Protozoan Proteins
  • erythrocyte membrane protein 1, Plasmodium falciparum
  • Interferon-gamma