Human leukocyte antigen E in human cytomegalovirus infection: friend or foe?

Acta Biochim Biophys Sin (Shanghai). 2012 Jul;44(7):551-4. doi: 10.1093/abbs/gms032. Epub 2012 May 9.

Abstract

Human cytomegalovirus (HCMV) is a well-studied β-herpesvirus virus, which adopts a variety of strategies to evade immune surveillance. It has been reported that in HCMV-infected cells, classical major histocompatibility (MHC) class I molecules are down-regulated, but the MHC class Ib molecule human leukocyte antigen (HLA)-E is normally expressed or even overexpressed on the cell surface. HLA-E has been first described to interact with CD94/NKG2 receptors expressed mainly on the surface of natural killer (NK) cells, thus confining its role to the regulation of NK-cell function. The engagement of CD94/NKG2A with HLA-E, with a signal peptide of the HCMV glycoprotein UL40, usually induces inhibitory signals. However, HLA-E also serves as a ligand for the TCR expressed by αβCD8(+) T cells. Recognition of peptides presented by HLA-E may result in CD8(+) effector T-cell activation. These findings will help to understand more on both pathogenic and protective roles of HLA-E in HCMV infection. In this review, we discussed recent studies about the roles of HLA-E in HCMV infection.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Cytomegalovirus / immunology*
  • Cytomegalovirus / metabolism
  • Cytomegalovirus Infections / immunology*
  • Cytomegalovirus Infections / metabolism
  • Cytomegalovirus Infections / virology
  • HLA-E Antigens
  • Histocompatibility Antigens Class I / immunology*
  • Histocompatibility Antigens Class I / metabolism
  • Humans
  • Killer Cells, Natural / immunology*
  • Killer Cells, Natural / metabolism
  • Models, Immunological
  • NK Cell Lectin-Like Receptor Subfamily D / immunology
  • NK Cell Lectin-Like Receptor Subfamily D / metabolism
  • Protein Binding
  • Protein Sorting Signals
  • Viral Proteins / immunology
  • Viral Proteins / metabolism

Substances

  • Histocompatibility Antigens Class I
  • KLRD1 protein, human
  • NK Cell Lectin-Like Receptor Subfamily D
  • Protein Sorting Signals
  • UL40 glycoprotein, Cytomegalovirus
  • Viral Proteins