Human cytomegalovirus suppresses Fas expression and function

J Gen Virol. 2014 Apr;95(Pt 4):933-939. doi: 10.1099/vir.0.058313-0. Epub 2014 Jan 6.

Abstract

Human cytomegalovirus (HCMV) is known to evade extrinsic pro-apoptotic pathways not only by downregulating cell surface expression of the death receptors TNFR1, TRAIL receptor 1 (TNFRSF10A) and TRAIL receptor 2 (TNFRSF10B), but also by impeding downstream signalling events. Fas (CD95/APO-1/TNFRSF6) also plays a prominent role in apoptotic clearance of virus-infected cells, so its fate in HCMV-infected cells needs to be addressed. Here, we show that cell surface expression of Fas was suppressed in HCMV-infected fibroblasts from 24 h onwards through the late phase of productive infection, and was dependent on de novo virus-encoded gene expression but not virus DNA replication. Significant levels of the fully glycosylated (endoglycosidase-H-resistant) Fas were retained within HCMV-infected cells throughout the infection within intracellular membranous structures. HCMV infection provided cells with a high level of protection against Fas-mediated apoptosis. Downregulation of Fas was observed with HCMV strains AD169, FIX, Merlin and TB40.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cells, Cultured
  • Cytomegalovirus / physiology*
  • Fibroblasts / virology
  • Host-Pathogen Interactions*
  • Humans
  • Immune Evasion*
  • fas Receptor / antagonists & inhibitors*
  • fas Receptor / immunology*

Substances

  • FAS protein, human
  • fas Receptor