title: Fusion of ubiquitin to HIV gag impairs human monocyte-derived dendritic cell maturation and reduces ability to induce gag T cell responses.
abstract: The efficient induction of CD8 T cell immunity is dependent on the processing and presentation of antigen on MHC class I molecules by professional antigen presenting cells (APC). To develop an improved T cell vaccine for HIV we investigated whether fusing the ubiquitin gene to the N terminus of the HIV gag gene enhanced targeting to the proteasome resulting in better CD8 T cell responses. Human monocyte derived dendritic cells (moDC), transduced with adenovirus vectors carrying either ubiquitinated or non-ubiquitinated gag transgene constructs, were co-cultured with autologous naïve T cells and T cell responses were measured after several weekly cycles of stimulation. Despite targeting of the ubiquitin gag transgene protein to the proteasome, ubiquitination did not increase CD8 T cell immune responses and in some cases diminished responses to gag peptides. There were no marked differences in cytokines produced from ubiquitinated and non-ubiquitinated gag stimulated cultures or in the expression of inhibitory molecules on expanded T cells. However, the ability of moDC transduced with ubiquitinated gag gene to upregulate co-stimulatory molecules was reduced, whilst no difference in moDC maturation was observed with a control ubiquitinated and non-ubiquitinated MART gene. Furthermore moDC transduced with ubiquitinated gag produced more IL-10 than transduction with unmodified gag. Thus failure of gag ubiquitination to enhance CD8 responses may be caused by suppression of moDC maturation. These results indicate that when designing a successful vaccine strategy to target a particular cell population, attention must also be given to the effect of the vaccine on APCs.
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Shanthi
authors: S
authors: Herath
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Adel
authors: A
authors: Benlahrech
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Timos
authors: T
authors: Papagatsias
authors: School of Biological Science, Royal Holloway University of London, Egham, Surrey, United Kingdom.
authors: Takis
authors: T
authors: Athanasopoulos
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Zineb
authors: Z
authors: Bouzeboudjen
authors: Peter Gorer Department of Immunobiology, Guys Hospital, Kings College London, London, United Kingdom.
authors: Catherine
authors: C
authors: Hervouet
authors: Peter Gorer Department of Immunobiology, Guys Hospital, Kings College London, London, United Kingdom.
authors: Linda
authors: L
authors: Klavinskis
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Andrea
authors: A
authors: Meiser
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Peter
authors: P
authors: Kelleher
authors: School of Biological Science, Royal Holloway University of London, Egham, Surrey, United Kingdom.
authors: George
authors: G
authors: Dickson
authors: Department of Immunology, Imperial College London, Chelsea and Westminster Hospital, London, United Kingdom.
authors: Steven
authors: S
authors: Patterson
mesh_terms: D016915:AIDS Vaccines / Q000235:genetics* / Q000276:immunology; D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology; D002478:Cells, Cultured; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism / Q000821:virology; D015658:HIV Infections / Q000276:immunology / Q000517:prevention & control*; D015497:HIV-1 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes; D014161:Transduction, Genetic; D019076:Transgenes; D025801:Ubiquitin / Q000235:genetics* / Q000276:immunology; D054875:Ubiquitination; D054301:gag Gene Products, Human Immunodeficiency Virus / Q000235:genetics* / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D025801:Ubiquitin; D054301:gag Gene Products, Human Immunodeficiency Virus