Isolation and Characterization of Exosomes Released by EBV-Immortalized Cells

Epstein-Barr virus is an oncogenic herpesvirus associated with several human malignancies. Although the details of the molecular steps involved in EBV-mediated cell transformation and immune evasion are not fully known, a number of viral products, including EBV latent proteins and non-protein coding RNAs have been shown to be involved, directly or indirectly in these processes. In recent years, a growing body of data indicates that some viruses are able to transport selected products to neighboring cells and induce biological changes by exploiting the exosome secretory pathway. Exosomes are nanovesicles secreted by virtually all cell types and present in most body fluids. Here, we describe the protocols used in our laboratory to isolate and characterize exosomes from EBV-infected, noninfected, and transfected cell lines.