title: Early Kinetics of the HLA Class I-Associated Peptidome of MVA.HIVconsv-Infected Cells.
abstract: Cytotoxic T cells substantially contribute to the control of intracellular pathogens such as human immunodeficiency virus type 1 (HIV-1). Here, we evaluated the immunopeptidome of Jurkat cells infected with the vaccine candidate MVA.HIVconsv, which delivers HIV-1 conserved antigenic regions by using modified vaccinia virus Ankara (MVA). We employed liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify 6,358 unique peptides associated with the class I human leukocyte antigen (HLA), of which 98 peptides were derived from the MVA vector and 7 were derived from the HIVconsv immunogen. Human vaccine recipients responded to the peptide sequences identified by LC-MS/MS. Peptides derived from the conserved HIV-1 regions were readily detected as early as 1.5 h after MVA.HIVconsv infection. Four of the seven conserved peptides were monitored between 0 and 3.5 h of infection by using quantitative mass spectrometry (Q-MS), and their abundance in HLA class I associations reflected levels of the whole HIVconsv protein in the cell. While immunopeptides delivered by the incoming MVA vector proteins could be detected, all early HIVconsv-derived immunopeptides were likely synthesized de novo. MVA.HIVconsv infection generally altered the composition of HLA class I-associated human (self) peptides, but these changes corresponded only partially to changes in the whole cell host protein abundance.
  
  
  OBJECTIVE
  The vast changes in cellular antigen presentation after infection of cells with a vectored vaccine, as shown here for MVA.HIVconsv, highlight the complexity of factors that need to be considered for efficient antigen delivery and presentation. Identification and quantitation of HLA class I-associated peptides by Q-MS will not only find broad application in T-cell epitope discovery but also inform vaccine design and allow evaluation of efficient epitope presentation using different delivery strategies.
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom nicola.ternette@ndm.ox.ac.uk.
authors: Nicola
authors: http://orcid.org/0000-0002-9283-0743
authors: N
authors: Ternette
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Peter D
authors: PD
authors: Block
authors: Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom Universitat de Barcelona, Barcelona, Spain.
authors: Álvaro
authors: Á
authors: Sánchez-Bernabéu
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Nicola
authors: N
authors: Borthwick
authors: Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom.
authors: Elisa
authors: E
authors: Pappalardo
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Sultan
authors: S
authors: Abdul-Jawad
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Beatrice
authors: B
authors: Ondondo
authors: Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Philip D
authors: PD
authors: Charles
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Lucy
authors: L
authors: Dorrell
authors: Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Benedikt M
authors: BM
authors: Kessler
authors: The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors: Tomáš
authors: T
authors: Hanke
mesh_terms: D016915:AIDS Vaccines / Q000276:immunology*; D000956:Antigens, Viral / Q000032:analysis*; D002853:Chromatography, Liquid; D005822:Genetic Vectors; D015497:HIV-1 / Q000276:immunology*; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D019169:Jurkat Cells; D010455:Peptides / Q000032:analysis*; D013602:T-Lymphocytes, Cytotoxic / Q000737:chemistry* / Q000276:immunology; D053719:Tandem Mass Spectrometry; D013997:Time Factors; D014614:Vaccines, Synthetic / Q000276:immunology; D014616:Vaccinia virus / Q000235:genetics / Q000276:immunology
chemical_list: D016915:AIDS Vaccines; D000956:Antigens, Viral; D015395:Histocompatibility Antigens Class I; D010455:Peptides; D014614:Vaccines, Synthetic