MALIGNANT-LYMPHOMAS INDUCED BY AN EPSTEIN-BARR VIRUS-RELATED HERPESVIRUS FROM MACACA ARCTOIDES - A RABBIT MODEL

Animal models for Epstein-Barr virus (EBV) are restricted to some spec ies of new-world monkeys which develop malignant lymphoid tumours or b enign lymphoproliferative diseases after virus inoculation. Similar pa thological features were induced in rabbits by the EBV-related herpesv irus of Macaca arctoides (HVMA). In this study 17 of 32 rabbits infect ed with varying amounts of HVMA produced from MAL-1 cells developed ly mphoproliferative disorders. In 13 rabbits high-grade malignant lympho mas were detected, 4 rabbits revealed the histopathological feature of lymphoid hyperplasia. These lymphoproliferations were shown to be ass ociated with HVMA by PCR and by the expression of EBV-like RNAs (EBER) in 14 and 10 cases, respectively. The homology in the polymerase gene region between DNA from EBV and HVMA, and from HVMA and the malignant tissue was found to be 94.8% and 100%, respectively. All the infected animals produced antibodies to antigens corresponding to early and la te EBV proteins. By studying the HVMA expression in MAL-I cells EBV-li ke proteins expressed in latency (EBNA1 and EBNA2) and in the lytic cy cle (VCA, EA) were detected. Our findings suggested that HVMA caused a symptomatic infection in rabbits with pathological features that fit the conditions of an animal model suitable for testing antiviral drugs and vaccines against EBV.