A Multi-Omics Approach to Epstein-Barr Virus (EBV) Immortalization of B-Cells Reveals Viral-Induced Changes in Chromatin Accessibility and Nucleotide Metabolism

Epstein-Barr Virus (EBV) immortalizes resting B-lymphocytes through a highly orchestrated process involving extensive reprogramming of host transcription and metabolism. Here, we use multiple omics-based approaches concurrently across the time course of B-cell infection to investigate the underlying mechanisms that control EBV-induced B-cell immortalization. ATAC-seq revealed that over a third of accessible chromatin is altered with the most perturbed sites overlapping Ets-family, including PU.1 and RUNX1 transcription factors. EBV nuclear antigens (EBNAs) clustered with different gene categories and RNA-seq identified the transcriptional response of these gene. Focusing on EBNA1 revealed a selection of gene targets involved in nucleotide metabolism. Metabolomics indicated that adenosine and purine metabolism are significantly altered by EBV immortalization, and we validated that adenosine deaminase (ADA) is a direct and critical target of EBNA1 and the EBV-directed immortalization process. These findings reveal that purine metabolism and ADA inhibitors may be a useful therapeutic for EBV-driven lymphoid cancers Overall design: ATAC-seq and RNA-seq of B cells during 0, 2, 7 and 21 days of EBV infection