Ebola virus enters host cells by macropinocytosis and clathrin-mediated endocytosis

J Infect Dis. 2011 Nov;204 Suppl 3(Suppl 3):S957-67. doi: 10.1093/infdis/jir326.

Abstract

Virus entry into host cells is the first step of infection and a crucial determinant of pathogenicity. Here we show that Ebola virus-like particles (EBOV-VLPs) composed of the glycoprotein GP(1,2) and the matrix protein VP40 use macropinocytosis and clathrin-mediated endocytosis to enter cells. EBOV-VLPs applied to host cells induced actin-driven ruffling and enhanced FITC-dextran uptake, which indicated macropinocytosis as the main entry mechanism. This was further supported by inhibition of entry through inhibitors of actin polymerization (latrunculin A), Na(+)/H(+)-exchanger (EIPA), and PI3-kinase (wortmannin). A fraction of EBOV-VLPs, however, colocalized with clathrin heavy chain (CHC), and VLP uptake was reduced by CHC small interfering RNA transfection and expression of the dominant negative dynamin II-K44A mutant. In contrast, we found no evidence that EBOV-VLPs enter cells via caveolae. This work identifies macropinocytosis as the major, and clathrin-dependent endocytosis as an alternative, entry route for EBOV particles. Therefore, EBOV seems to utilize different entry pathways depending on both cell type and virus particle size.

Publication types

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

MeSH terms

  • Actins / physiology
  • Amiloride / analogs & derivatives
  • Amiloride / pharmacology
  • Androstadienes / pharmacology
  • Animals
  • Bridged Bicyclo Compounds, Heterocyclic / pharmacology
  • Caveolin 1 / metabolism
  • Cell Line
  • Clathrin / physiology*
  • Ebolavirus / physiology*
  • Endocytosis / physiology*
  • Epithelial Cells / metabolism
  • Epithelial Cells / virology*
  • Gene Silencing
  • Host-Pathogen Interactions
  • Humans
  • RNA, Small Interfering
  • Signal Transduction
  • Thiazolidines / pharmacology
  • Virus Internalization*
  • Virus Replication
  • Wortmannin

Substances

  • Actins
  • Androstadienes
  • Bridged Bicyclo Compounds, Heterocyclic
  • Caveolin 1
  • Clathrin
  • RNA, Small Interfering
  • Thiazolidines
  • Amiloride
  • latrunculin A
  • ethylisopropylamiloride
  • Wortmannin