Human cytomegalovirus (HCMV) is an important pathogen with multiple immune evasion strategies, including virally facilitated degradation of host antiviral restriction factors. Here, we describe a multiplexed approach to discover proteins with innate immune function on the basis of active degradation by the proteasome or lysosome during early-phase HCMV infection. Using three orthogonal proteomic/transcriptomic screens to quantify protein degradation, with high confidence we identified 35 proteins enriched in antiviral restriction factors. A final screen employed a comprehensive panel of viral mutants to predict viral genes that target >250 human proteins. This approach revealed that helicase-like transcription factor (HLTF), a DNA helicase important in DNA repair, potently inhibits early viral gene expression but is rapidly degraded during infection. The functionally unknown HCMV protein UL145 facilitates HLTF degradation by recruiting the Cullin4 E3 ligase complex. Our approach and data will enable further identifications of innate pathways targeted by HCMV and other viruses.
- MeSH
- cytomegalovirové infekce genetika imunologie virologie MeSH
- Cytomegalovirus genetika imunologie fyziologie MeSH
- DNA vazebné proteiny chemie genetika imunologie MeSH
- imunitní únik MeSH
- lidé MeSH
- proteiny chemie genetika imunologie MeSH
- proteomika MeSH
- stabilita proteinů MeSH
- transkripční faktory chemie genetika imunologie MeSH
- virové proteiny chemie genetika imunologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
CD58 is an adhesion molecule that is known to play a critical role in costimulation of effector cells and is intrinsic to immune synapse structure. Herein, we describe a virally encoded gene that inhibits CD58 surface expression. Human cytomegalovirus (HCMV) UL148 was necessary and sufficient to promote intracellular retention of CD58 during HCMV infection. Blocking studies with antagonistic anti-CD58 mAb and an HCMV UL148 deletion mutant (HCMV∆UL148) with restored CD58 expression demonstrated that the CD2/CD58 axis was essential for the recognition of HCMV-infected targets by CD8+ HCMV-specific cytotoxic T lymphocytes (CTLs). Further, challenge of peripheral blood mononuclear cells ex vivo with HCMV∆UL148 increased both CTL and natural killer (NK) cell degranulation against HCMV-infected cells, including NK-driven antibody-dependent cellular cytotoxicity, showing that UL148 is a modulator of the function of multiple effector cell subsets. Our data stress the effect of HCMV immune evasion functions on shaping the immune response, highlighting the capacity for their potential use in modulating immunity during the development of anti-HCMV vaccines and HCMV-based vaccine vectors.
- MeSH
- buněčná imunita * MeSH
- buňky NK imunologie patologie MeSH
- CD8-pozitivní T-lymfocyty imunologie patologie MeSH
- cytomegalovirové infekce genetika imunologie patologie MeSH
- Cytomegalovirus genetika imunologie MeSH
- imunitní únik * MeSH
- lidé MeSH
- proteiny virové fúze genetika imunologie MeSH
- transformované buněčné linie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The human cytomegalovirus (HCMV) US12 family consists of ten sequentially arranged genes (US12-21) with poorly characterized function. We now identify novel natural killer (NK) cell evasion functions for four members: US12, US14, US18 and US20. Using a systematic multiplexed proteomics approach to quantify ~1300 cell surface and ~7200 whole cell proteins, we demonstrate that the US12 family selectively targets plasma membrane proteins and plays key roles in regulating NK ligands, adhesion molecules and cytokine receptors. US18 and US20 work in concert to suppress cell surface expression of the critical NKp30 ligand B7-H6 thus inhibiting NK cell activation. The US12 family is therefore identified as a major new hub of immune regulation.
- MeSH
- buňky NK imunologie MeSH
- Cytomegalovirus imunologie patogenita MeSH
- imunitní únik MeSH
- imunologické faktory antagonisté a inhibitory MeSH
- interakce hostitele a patogenu * MeSH
- lidé MeSH
- membránové proteiny antagonisté a inhibitory MeSH
- proteomika MeSH
- virové proteiny metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH