title: MHC class I up-regulation by flaviviruses: Immune interaction with unknown advantage to host or pathogen.
abstract: In contrast to many other viruses that escape from cytotoxic T cell recognition by down-regulating major histocompatibility complex class I-restricted antigen presentation, flavivirus infection of mammalian cells up-regulates cell surface expression of major histocompatibility complex class I molecules. Two putative mechanisms for flavivirus-induced major histocompatibility complex class I up-regulation, one via activation of the transcription factor NF-kappaB, the second by augmentation of peptide import into the lumen of the endoplasmic reticulum, are reviewed, and the biological effect of the flavivirus-mediated phenomenon on target cell recognition by natural killer and cytotoxic T cells is addressed. Finally, we speculate on the physiological role of flavivirus-mediated modulation of major histocompatibility complex class I antigen presentation in the context of the biology of flavivirus transmission between the vertebrate host and arthropod vector and suggest that it may represent a strategy for immune evasion from the natural killer cell response or, alternatively, that up-regulation of major histocompatibility complex class I is a by-product of flavivirus replication without significance for virus growth.
authors.affiliation: Division of Immunology and Genetics, John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia. Mario.Lobigs@anu.edu.au
authors.forename: Mario
authors.initials: M
authors.lastname: Lobigs
authors.forename: Arno
authors.initials: A
authors.lastname: Müllbacher
authors.forename: Matthias
authors.initials: M
authors.lastname: Regner
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000276:immunology; D005416:Flavivirus / Q000276:immunology*; D018177:Flavivirus Infections / Q000276:immunology* / Q000635:transmission; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D006801:Humans; D007304:Insect Viruses / Q000276:immunology*; D016328:NF-kappa B / Q000276:immunology; D021381:Protein Transport / Q000276:immunology; D015854:Up-Regulation
chemical_list: D015395:Histocompatibility Antigens Class I; D016328:NF-kappa B