Abstract # 48:

Scheduled for Thursday, August 18, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation

A Novel Type-D Simian Retrovirus (SRV) in Newly Imported M. nemestrina Similar to Endogenous Langur Monkey Retrovirus; Evidence of Cross-Genus Transmission

R. Grant1, C. Vinh1, R. Watanabe1, R. McLain1, L. Kuller1, B. Poland1, L. Jones-Engel1, D. Iskandriati2, J. Pamungkas2, R. Kyes1 and D. Anderson1
1University of Washington, National Primate Research Center, Box 357330, Seattle, WA 98195, USA, 2Primate Research Center, Bogor Agricultural University, Bogor, Indonesia
     Type-D simian retrovirus (SRV) is transmitted rapidly in macaques and can cause simian AIDS. A newly described SRV-mn from pigtailed macaques (M. nemestrina) in Indonesia and in U.S. quarantine is most closely related to the endogenous type-D retrovirus found in langur species. The unexpected isolation of a new SRV type in pigtailed macaques, related to the langur virus, is of significance because it is the first evidence of horizontal cross-genus transmission of an endogenous virus. Endogenous retroviruses are present in all cells in all mammalian species and are normally thought to be non-infectious. However, langurs have long been known to produce infectious viruses from their endogenous sequences. We have genetically characterized the virus from langur monkeys (Trachypithecus auratus and T. obscurus) and found it to be greater than 92% identical to the new SRV-mn. Other SRV serotypes are only 70-85% similar to each other in the same region of the genome. Phylogenetic analysis of the sequences and culture characteristics confirm the close relationship of these two viruses. Further evidence is needed to confirm that langurs were the source of the SRV-mn but we have shown that the langur type D virus is the closest known relative of the new pigtail SRV and the degree of similarity between the two is higher than the similarities between SRV isolates from different macaque species.