Urea-mediated cross-presentation of soluble Epstein-Barr virus BZLF1 protein.
Soluble extracellular proteins usually do not enter the endogenous human leukocyte antigen (HLA) I-dependent presentation pathway of antigen-presenting cells, strictly impeding their applicability for the re-stimulation of protein-specific CD8(+) cytotoxic T lymphocytes (CTL). Here we present for the Epstein-Barr virus (EBV) BZLF1 a novel strategy that facilitates protein translocation into antigen-presenting cells by its solubilisation in high molar urea and subsequent pulsing of cells in presence of low molar urea. Stimulation of PBMC from HLA-matched EBV-seropositive individuals with urea-treated BZLF1 but not untreated BZLF1 induces an efficient reactivation of BZLF1-specific CTL. Urea-treated BZLF1 (uBZLF1) enters antigen-presenting cells in a temperature-dependent manner by clathrin-mediated endocytosis and is processed by the proteasome into peptides that are bound to nascent HLA I molecules. Dendritic cells and monocytes but also B cells can cross-present uBZLF1 in vitro. The strategy described here has potential for use in the development of improved technologies for the monitoring of protein-specific CTL.
Barabas
Sascha
S
Institute of Medical Microbiology, University of Regensburg, Germany.
Gary
Regina
R
Bauer
Tanja
T
Lindner
Juha
J
Lindner
Petra
P
Weinberger
Birgit
B
Jilg
Wolfgang
W
Wolf
Hans
H
Deml
Ludwig
L
D000938:Antigen-Presenting Cells / Q000276:immunology / Q000821:virology; D001402:B-Lymphocytes; D002478:Cells, Cultured; D045142:Cross-Priming / Q000276:immunology*; D003713:Dendritic Cells; D004705:Endocytosis; D004854:Herpesvirus 4, Human / Q000737:chemistry*; D015395:Histocompatibility Antigens Class I; D006801:Humans; D008722:Methods; D009000:Monocytes; D012995:Solubility; D015534:Trans-Activators / Q000276:immunology*; D014508:Urea
C063676:BZLF1 protein, Herpesvirus 4, Human; D015395:Histocompatibility Antigens Class I; D015534:Trans-Activators; D014508:Urea