Projects per year
Abstract
Despite triggering strong immune responses, Epstein-Barr virus (EBV) has colonized more than 90% of the adult human population. Successful persistence of EBV depends on the establishment of a balance between host immune responses and viral immune evasion. Here we have extended our studies on the EBV-encoded BILF1 protein, which was recently identified as an immunoevasin that functioned by enhancing degradation of MHC-I via lysosomes. We now demonstrate that disruption of the EKT signalling motif of BILF1 by a K122A mutation impairs the ability of BILF1 to enhance endocytosis of surface MHC-I molecules, whilst subsequent lysosomal degradation was impaired by deletion of the 21 residue C-terminus tail of BILF1. Furthermore, we identified another mechanism of BILF1 immuno-modulation, which targets newly-synthesized MHC-I/peptide complexes en route to the cell surface. Importantly, although the diversion of MHC-I on the exocytic pathway caused a relatively modest reduction in cell surface MHC-I, presentation of endogenously processed target peptides to immune CD8(+) effector T cells was reduced by around 65%. The immune-modulating functions of BILF1 in the context of the whole virus were confirmed in cells lytically infected with a recombinant EBV in which BILF1 was deleted. This study therefore extends our initial observations on BILF1 to show that this immunoevasin can target MHC-I antigen presentation via both the exocytic and endocytic trafficking pathways. The results also emphasise the merits of including functional T cell recognition assays to gain a more complete picture of immunoevasin effects on the antigen presentation pathway.
Original language | English |
---|---|
Pages (from-to) | 1604-1614 |
Number of pages | 11 |
Journal | Journal of virology |
Volume | 85 |
Issue number | 4 |
DOIs | |
Publication status | Published - 1 Feb 2011 |
Fingerprint
Dive into the research topics of 'The Epstein-Barr virus-encoded BILF1 protein modulates immune recognition of endogenously processed antigen by targeting MHC class I molecules trafficking on both the exocytic and endocytic pathways.'. Together they form a unique fingerprint.Projects
- 1 Finished