Surface expression of HLA-E, an inhibitor of natural killer cells, enhanced by human cytomegalovirus gpUL40.
The nonclassical major histocompatibility complex (MHC) class I molecule HLA-E inhibits natural killer (NK) cell-mediated lysis by interacting with CD94/NKG2A receptors. Surface expression of HLA-E depends on binding of conserved peptides derived from MHC class I molecules. The same peptide is present in the leader sequence of the human cytomegalovirus (HCMV) glycoprotein UL40 (gpUL40). It is shown that, independently of the transporter associated with antigen processing, gpUL40 can up-regulate expression of HLA-E, which protects targets from NK cell lysis. While classical MHC class I molecules are down-regulated, HLA-E is up-regulated by HCMV. Induction of HLA-E surface expression by gpUL40 may represent an escape route for HCMV.
Tomasec
P
P
Department of Medicine, University of Wales College of Medicine, Cardiff CF14 4XN, UK.
Braud
V M
VM
Rickards
C
C
Powell
M B
MB
McSharry
B P
BP
Gadola
S
S
Cerundolo
V
V
Borysiewicz
L K
LK
McMichael
A J
AJ
Wilkinson
G W
GW
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D015703:Antigens, CD; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D002478:Cells, Cultured; D017124:Conserved Sequence; D003587:Cytomegalovirus / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D003602:Cytotoxicity, Immunologic; D015536:Down-Regulation; D006680:HLA Antigens / Q000276:immunology / Q000378:metabolism*; D015395:Histocompatibility Antigens Class I / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D021382:Protein Sorting Signals / Q000737:chemistry / Q000378:metabolism*; D011971:Receptors, Immunologic / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D014162:Transfection; D015854:Up-Regulation; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000097625:HLA-E Antigens
D015703:Antigens, CD; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I; D000075362:Leukocyte Immunoglobulin-like Receptor B1; D021382:Protein Sorting Signals; D011971:Receptors, Immunologic; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D000097625:HLA-E Antigens; C105299:LILRB1 protein, human; C404228:UL40 glycoprotein, Cytomegalovirus