In vitro Epstein-Barr virus infection model of rabbit lymphocytes from peripheral blood or spleen.

Most humans become lifelong carriers of Epstein-Barr virus (EBV) by adulthood. Primary EBV infection in adolescents causes infectious mononucleosis. EBV infection is associated with various diseases, neoplasms and hematological disorders. Recently, we reported that EBV can infect rabbits by intravenous, intranasal and/or peroral inoculation, which caused primary EBV infection in rabbits with heterogeneous host reactions. Some rabbits showed chronic and lifelong EBV infection with hemophagocytosis. In this study, to reveal detailed mechanisms in rabbit EBV infection, an in vitro investigation was performed. We elucidated that: (1) EBV can infect rabbit peripheral blood mononuclear cells and splenic lymphocytes in vitro, because EBV gene expressions were confirmed. (2) It is highly likely that the B cell is the main target cell of rabbit EBV infection and is immortalized similar to humans. (3) CD8+ T cells increased in the rabbit in vivo model after EBV inoculation, whereas an increase of B cells occurred after their transient decrease. These data suggest that EBV-infected B cells were proliferated, while CD8+ T cells increased to recognize and kill them. This system may explain the paths of rabbit EBV infection and host reaction, simulating human EBV infection. In vitro studies will be helpful to reveal the pathogenesis of rabbit EBV infection and EBV-associated diseases.