Fig. 3. Characterization of isolated exosomes. The electron microscopy analysis showed that exosomes were typically cup-shaped, with an average diameter ranging from 80 to 120 nm (scare bar: 100 nm, black arrow) (A). Western blot analysis of exosomes and cell lysates showed that GRP78 was only detected in cell lysates, and a band for Hsp70 was observed in exosomes and cell lysates (B). Exo-N represent exosomes from un-infected cells, Exo-R represent exosomes from REV infected cells; Exo-J represent exosomes from ALV-J infected cells; Exo-RJ represent exosomes from REV and ALV-J co-infected cells.

ALV-J, avian leukosis virus subgroup J; REV, reticuloendotheliosis virus; GRP78, glucose-regulated protein 78.