Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria

Nat Commun. 2016 Oct 10:7:12727. doi: 10.1038/ncomms12727.

Abstract

Malaria remains one of the greatest public health challenges worldwide, particularly in sub-Saharan Africa. The clinical outcome of individuals infected with Plasmodium falciparum parasites depends on many factors including host systemic inflammatory responses, parasite sequestration in tissues and vascular dysfunction. Production of pro-inflammatory cytokines and chemokines promotes endothelial activation as well as recruitment and infiltration of inflammatory cells, which in turn triggers further endothelial cell activation and parasite sequestration. Inflammatory responses are triggered in part by bioactive parasite products such as hemozoin and infected red blood cell-derived extracellular vesicles (iRBC-derived EVs). Here we demonstrate that such EVs contain functional miRNA-Argonaute 2 complexes that are derived from the host RBC. Moreover, we show that EVs are efficiently internalized by endothelial cells, where the miRNA-Argonaute 2 complexes modulate target gene expression and barrier properties. Altogether, these findings provide a mechanistic link between EVs and vascular dysfunction during malaria infection.

Publication types

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

MeSH terms

  • Argonaute Proteins / metabolism*
  • Blood Vessels / metabolism*
  • Brain / blood supply
  • Cell Line
  • Endocytosis
  • Endothelial Cells / metabolism
  • Erythrocytes / parasitology*
  • Erythrocytes / ultrastructure
  • Extracellular Vesicles / metabolism*
  • Extracellular Vesicles / ultrastructure
  • Gene Expression Regulation
  • Gene Silencing
  • Humans
  • Malaria, Falciparum / metabolism*
  • Malaria, Falciparum / parasitology*
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Microvessels / cytology
  • RNA-Induced Silencing Complex / metabolism

Substances

  • AGO2 protein, human
  • Argonaute Proteins
  • MIRN451 microRNA, human
  • MicroRNAs
  • RNA-Induced Silencing Complex