title: Human herpesvirus 7 u21 downregulates classical and nonclassical class I major histocompatibility complex molecules from the cell surface.
abstract: Herpesviruses have evolved numerous strategies to evade detection by the immune system. Notably, most of the herpesviruses interfere with viral antigen presentation to cytotoxic T lymphocytes (CTLs) by removing class I major histocompatibility complex (MHC) molecules from the infected cell surface. Clearly, since the herpesviruses have evolved an extensive array of mechanisms to remove class I MHC molecules from the cell surface, this strategy serves them well. However, class I MHC molecules often serve as inhibitory ligands for NK cells, so viral downregulation of all class I MHC molecules should leave the infected cell open to NK cell attack. Some viruses solve this problem by selectively downregulating certain class I MHC products, leaving other class I products at the cell surface to serve as inhibitory NK cell ligands. Here, we show that human herpesvirus 7 (HHV-7) U21 binds to and downregulates all of the human class I MHC gene products, as well as the murine class I molecule H-2K(b). HHV-7-infected cells must therefore possess other means of escaping NK cell detection.
authors.affiliation: Department of Microbiology, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
authors.forename: Nathan A
authors.initials: NA
authors.lastname: May
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Glosson
authors.forename: Amy W
authors.initials: AW
authors.lastname: Hudson
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000502:physiology*; D002460:Cell Line; D002478:Cells, Cultured; D015536:Down-Regulation; D016199:Herpesvirus 7, Human / Q000276:immunology* / Q000472:pathogenicity*; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis* / Q000276:immunology*; D006801:Humans; D051379:Mice; D011485:Protein Binding; D025941:Protein Interaction Mapping; D014764:Viral Proteins / Q000502:physiology*
chemical_list: D002352:Carrier Proteins; D015395:Histocompatibility Antigens Class I; C488324:U21 glycoprotein, human herpesvirus 7; D014764:Viral Proteins