MicroRNAs (miRNAs) from viruses, such as those from Epstein-Barr virus (EBV), can be secreted via exosomes and function in recipient cells. This study demonstrates that EBV-infected B cells secrete exosomes containing EBV-encoded miRNAs, which are then internalized by uninfected cells, such as monocyte-derived dendritic cells (MoDC), leading to gene silencing. The EBV-encoded miRNAs, including BHRF1 and BART, are transferred through exosomes and mediate repression of target genes, such as CXCL11, in recipient cells. This process is dose-dependent and functional, as shown by luciferase assays. The study also shows that EBV-miRNAs are present in both B-cell and non-B-cell fractions in peripheral blood mononuclear cells from patients with high EBV loads, suggesting miRNA transfer in vivo. The findings indicate that exosome-mediated miRNA transfer is a potential mechanism for intercellular communication and immune regulation, with implications for viral strategies to evade host immune responses. The study highlights the role of exosomes in delivering miRNAs to subcellular sites of gene repression, contributing to the understanding of viral pathogenesis and immune modulation.MicroRNAs (miRNAs) from viruses, such as those from Epstein-Barr virus (EBV), can be secreted via exosomes and function in recipient cells. This study demonstrates that EBV-infected B cells secrete exosomes containing EBV-encoded miRNAs, which are then internalized by uninfected cells, such as monocyte-derived dendritic cells (MoDC), leading to gene silencing. The EBV-encoded miRNAs, including BHRF1 and BART, are transferred through exosomes and mediate repression of target genes, such as CXCL11, in recipient cells. This process is dose-dependent and functional, as shown by luciferase assays. The study also shows that EBV-miRNAs are present in both B-cell and non-B-cell fractions in peripheral blood mononuclear cells from patients with high EBV loads, suggesting miRNA transfer in vivo. The findings indicate that exosome-mediated miRNA transfer is a potential mechanism for intercellular communication and immune regulation, with implications for viral strategies to evade host immune responses. The study highlights the role of exosomes in delivering miRNAs to subcellular sites of gene repression, contributing to the understanding of viral pathogenesis and immune modulation.