Critical role of the neutrophil-associated high-affinity receptor for IgE in the pathogenesis of experimental cerebral malaria

J Exp Med. 2011 Oct 24;208(11):2225-36. doi: 10.1084/jem.20110845. Epub 2011 Oct 3.

Abstract

The role of the IgE-FcεRI complex in malaria severity in Plasmodium falciparum-hosting patients is unknown. We demonstrate that mice genetically deficient for the high-affinity receptor for IgE (FcεRIα-KO) or for IgE (IgE-KO) are less susceptible to experimental cerebral malaria (ECM) after infection with Plasmodium berghei (PbANKA). Mast cells and basophils, which are the classical IgE-expressing effector cells, are not involved in disease as mast cell-deficient and basophil-depleted mice developed a disease similar to wild-type mice. However, we show the emergence of an FcεRI(+) neutrophil population, which is not observed in mice hosting a non-ECM-inducing PbNK65 parasite strain. Depletion of this FcεRI(+) neutrophil population prevents ECM, whereas transfer of this population into FcεRIα-KO mice restores ECM susceptibility. FcεRI(+) neutrophils preferentially home to the brain and induce elevated levels of proinflammatory cytokines. These data define a new pathogenic mechanism of ECM and implicate an FcεRI-expressing neutrophil subpopulation in malaria disease severity.

MeSH terms

  • Adoptive Transfer
  • Animals
  • Basophils / cytology
  • Basophils / immunology
  • Cytokines / immunology
  • Eosinophils / cytology
  • Eosinophils / immunology
  • Female
  • Immunoglobulin E / genetics
  • Immunoglobulin E / immunology*
  • Malaria, Cerebral / immunology*
  • Malaria, Cerebral / parasitology
  • Malaria, Cerebral / pathology*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Neutrophils / cytology
  • Neutrophils / immunology*
  • Plasmodium berghei / immunology
  • Plasmodium berghei / pathogenicity
  • Protein Isoforms / genetics
  • Protein Isoforms / immunology
  • Receptors, IgE / genetics
  • Receptors, IgE / immunology*

Substances

  • Cytokines
  • Protein Isoforms
  • Receptors, IgE
  • Immunoglobulin E