High levels of retroperitoneal fibromatosis (RF)-associated herpesvirus in RF lesions in macaques are associated with ORF73 LANA expression in spindleoid tumour cells

• Published in: Journal of general virology Vol. 87; no. 12; pp. 3529 - 3538
• Main Authors: Bruce, A.G, Bakke, A.M, Bielefeldt-Ohmann, H, Ryan, J.T, Thouless, M.E, Tsai, C.C, Rose, T.M
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01-12-2006; Society for General Microbiology
• Subjects: Animals; Antigens, Viral - biosynthesis; Antigens, Viral - immunology; Biological and medical sciences; Disease Models, Animal; DNA, Viral - analysis; DNA, Viral - genetics; Fundamental and applied biological sciences. Psychology; Herpesviridae Infections - complications; Herpesviridae Infections - virology; Human herpesvirus 8; Immunohistochemistry; Kaposi's sarcoma-associated herpesvirus; Macaca; Macaca mulatta; Macaca nemestrina; Medical sciences; Microbiology; Miscellaneous; neoplasms; Nuclear Proteins - biosynthesis; Nuclear Proteins - immunology; polymerase chain reaction; Polymerase Chain Reaction - methods; Retroperitoneal Neoplasms - complications; Retroperitoneal Neoplasms - pathology; Retroperitoneal Neoplasms - virology; Rhadinovirus; Rhadinovirus - genetics; Rhadinovirus - metabolism; Rhadinovirus - physiology; Simian Acquired Immunodeficiency Syndrome - complications; Spleen - virology; Statistics as Topic; Tumor Virus Infections - complications; Tumor Virus Infections - virology; Tumors; Virology; Pseudotumor; Virus; Microbiology; Herpesviridae; Benign neoplasm; Lesion; Tumor cell; Fibromatosis; Virology
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/vir.0.82339-0

Two distinct lineages of rhadinoviruses related to Kaposi's sarcoma (KS)-associated herpesvirus (KSHV; Human herpesvirus 8), the causative agent of KS, have been identified. In macaques, the RV1 lineage is represented by retroperitoneal fibromatosis (RF) herpesvirus (RFHV), the homologue of KSHV, whilst the RV2 lineage is represented by rhesus rhadinovirus (RRV), a more distantly related virus. Real-time quantitative PCR was used to estimate the loads of RV1 and RV2 rhadinoviruses in simian acquired immunodeficiency syndrome-associated RF (SAIDS-RF), a neoplasm of macaques with similarities to AIDS-associated KS. Both RV1 and RV2 rhadinoviruses were detected in macaques with RF. The RV1 loads were 220- to 4300-fold higher in RF tumours than in spleen, showing a strong tumour association (mean loads of 1 800 000 vs 2900 copies per 10(6) cells in tumours and spleen, respectively). In contrast, RV2 loads in the RF tumours were 100-fold lower than RV1 loads and showed similar levels in tumours and spleen (mean loads of 16 000 vs 24 000 copies per 10(6) cells, respectively). Immunostaining with antibodies reactive against RFHV ORF73 latency-associated nuclear antigen (LANA) showed intense nuclear staining of the spindleoid RF tumour cells. Correlation of viral load and the number of LANA-positive cells indicated that RF tumour cells contained multiple copies of the RFHV genome per cell. This pattern of infectivity is similar to that seen in KS tumours latently infected with KSHV. Our study demonstrates similarities in the biology of KSHV and RFHV and supports a role for RFHV in the aetiology of SAIDS-RF.