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The interaction between immune cells and virus-infected targets involves multiple plasma membrane (PM) proteins. A systematic study of PM protein modulation by vaccinia virus (VACV), the paradigm of host regulation, has the potential to reveal not only novel viral immune evasion mechanisms, but also novel factors critical in host immunity. Here, >1000 PM proteins were quantified throughout VACV infection, revealing selective downregulation of known T and NK cell ligands including HLA-C, downregulation of cytokine receptors including IFNAR2, IL-6ST and IL-10RB, and rapid inhibition of expression of certain protocadherins and ephrins, candidate activating immune ligands. Downregulation of most PM proteins occurred via a proteasome-independent mechanism. Upregulated proteins included a decoy receptor for TRAIL. Twenty VACV-encoded PM proteins were identified, of which five were not recognised previously as such. Collectively, this dataset constitutes a valuable resource for future studies on antiviral immunity, host-pathogen interaction, poxvirus biology, vector-based vaccine design and oncolytic therapy.

Chronic active Epstein Barr Virus (CAEBV) is a rare condition occurring in previously healthy individuals associated with persistent EBV viraemia, fever, lymphadenopathy and hepatosplenomegaly. Viral deletions have been found in CAEBV and other lymphomas. However, it is unclear how stable these deletions are, whether they are present in different sites and how they evolve overtime. We sequenced fourteen longitudinal blood samples from three European CAEBV patients and compared with CAEBV saliva samples and other sequences from EBV-related conditions. We observed large EBV deletions in blood, but not saliva from CAEBV patients. Deletions were stable over time but were lost following successful treatment. Our results are consistent with the likelihood that certain deletions in the virus from CAEBV patients are associated with the evolution and persistence of haematological clones. We propose that the loss of deletions following successful treatment should be investigated as a potential biomarker to aid CAEBV management.