title: Cutting edge: activation of HIV-1 transcription by the MHC class II transactivator.
abstract: Both macrophages and activated CD4+ T cells can be productively infected by HIV-1, and both cell types express MHC class II molecules. Expression of MHC class II proteins in these cells is regulated by a specific transcriptional coactivator, the class II transactivator (CIITA). In this study, we report for the first time that CIITA expression profoundly influences HIV-1 replication. Stable expression of CIITA in Jurkat cells markedly increased 1) HIV-1 replication as assessed by the p24 Ag production and 2) luciferase expression after transfection with full-length provirus or long terminal repeat constructs. Similarly, transient expression of CIITA increased provirus expression as well as long terminal repeat promoter activity in 293 and HeLa-T4 cells. In contrast, mutant forms of CIITA did not increase HIV-1 expression. This study shows that expression of CIITA increases HIV-1 replication through a transcriptional mechanism.
authors.affiliation: Department of Immunology/Microbiology, Rush University, Chicago, IL 60612, USA. msaifudd@rush.edu
authors.forename: M
authors.initials: M
authors.lastname: Saifuddin
authors.forename: K A
authors.initials: KA
authors.lastname: Roebuck
authors.forename: Ch
authors.initials: Ch
authors.lastname: Chang
authors.forename: J P
authors.initials: JP
authors.lastname: Ting
authors.forename: G T
authors.initials: GT
authors.lastname: Spear
mesh_terms: D002460:Cell Line; D015967:Gene Expression Regulation, Viral / Q000276:immunology; D005802:Genes, MHC Class II / Q000276:immunology*; D016325:HIV Long Terminal Repeat / Q000276:immunology; D015497:HIV-1 / Q000235:genetics* / Q000276:immunology*; D006684:HLA-DR Antigens / Q000096:biosynthesis / Q000235:genetics; D006367:HeLa Cells; D006801:Humans; D019169:Jurkat Cells; D009687:Nuclear Proteins; D015534:Trans-Activators / Q000502:physiology*; D014158:Transcription, Genetic / Q000276:immunology*; D015533:Transcriptional Activation / Q000276:immunology*; D014162:Transfection; D014779:Virus Replication / Q000276:immunology
chemical_list: D006684:HLA-DR Antigens; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D015534:Trans-Activators