Caveolar endocytosis is required for human PSGL-1-mediated enterovirus 71 infection

J Virol. 2013 Aug;87(16):9064-76. doi: 10.1128/JVI.00573-13. Epub 2013 Jun 12.

Abstract

Enterovirus 71 (EV71) causes hand, foot, and mouth disease and severe neurological disorders in children. Human scavenger receptor class B member 2 (hSCARB2) and P-selectin glycoprotein ligand-1 (PSGL-1) are identified as receptors for EV71. The underling mechanism of PSGL-1-mediated EV71 entry remains unclear. The endocytosis required for EV71 entry were investigated in Jurkat T and mouse L929 cells constitutively expressing human PSGL-1 (PSGL-1-L929) or human rhabdomyosarcoma (RD) cells displaying high SCARB2 but no PSGL-1 by treatment of specific inhibitors or siRNA. We found that disruption of clathrin-dependent endocytosis prevented EV71 infection in RD cells, while there was no influence in Jurkat T and PSGL-1-L929 cells. Disturbing caveolar endocytosis by specific inhibitor or caveolin-1 siRNA in Jurkat T and PSGL-1-L929 cells significantly blocked EV71 infection, whereas it had no effect on EV71 infection in RD cells. Confocal immunofluorescence demonstrated caveola, and EV71 was directly colocalized. pH-dependent endosomal acidification and intact membrane cholesterol were important for EV71 infection, as judged by the pretreatment of inhibitors that abrogated the infection. A receptor-dominated endocytosis of EV71 infection was observed: PSGL-1 initiates caveola-dependent endocytosis and hSCARB2 activates clathrin-dependent endocytosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Caveolin 1 / metabolism
  • Cell Line
  • Endocytosis*
  • Enterovirus A, Human / physiology*
  • Gene Knockdown Techniques
  • Humans
  • Membrane Glycoproteins / metabolism*
  • Mice
  • Microscopy, Confocal
  • Receptors, Virus / metabolism*
  • Virus Internalization*

Substances

  • Caveolin 1
  • Membrane Glycoproteins
  • P-selectin ligand protein
  • Receptors, Virus