Broussard S R, Comuzzie A G, Leighton K L, Leland M M, Whitehead E M, Allan J S
Department of Virology and Immunology, Southwest Foundation for Biomedical Research, 7620 N.W. Loop 410 at Military Drive, San Antonio, Texas 78228, USA.
Virology. 1997 Oct 27;237(2):349-59. doi: 10.1006/viro.1997.8797.
Simian foamy viruses (SFV) are exogenous retroviruses present in most if not all nonhuman primate species. Baboons and other African monkey species are known to harbor SFVs, yet there is presently no data in regard to their genetic relationship. Here we studied SFVs from baboons as compared to other SFVs isolated from a Hamlyn's guenon, a patas monkey, and a vervet. By Western blot analysis, the gag precursor proteins (p74/p70) were detected from all SFVs. In addition, the envelope glycoproteins from a vervet isolate (SFV-Agm2) were comparable in size to the env precursor gp130, the exterior glycoprotein (gp70), and the transmembrane protein (gp48) as detected by lentil lectin binding and radioimmunoprecipitation (RIPA). Molecular comparison of PCR amplified products from pol and LTR regions of each SFV demonstrated a close relationship among baboon SFVs while SFVs from patas, Hamlyn's guenon, and vervet clustered together. The baboon viruses only varied by 4% among each other in the LTR region; however, as much as 26% variation was noted when compared to the other African monkey SFVs. To determine the prevalence rate of SFV-Bab in our baboon colony, we employed both Western blotting and PCR analysis. Antibodies to SFV gag precursor proteins were seen in 7 of 10 infants; however, none were positive by PCR, suggesting that these infants were virus negative and that their antibodies were maternal in origin. Only one juvenile (1/10) and all adults (38/38) were infected with SFV. Taken together these results suggest that SFVs have arisen and diverged along with the evolution of their natural hosts. Furthermore, the high prevalence rates to SFV seen in adult baboons strongly suggest a sexual or oral routes of transmission.
猿猴泡沫病毒（SFV）是存在于大多数（即便不是全部）非人灵长类物种中的外源性逆转录病毒。已知狒狒和其他非洲猴类物种携带SFV，但目前尚无关于它们遗传关系的数据。在此，我们研究了来自狒狒的SFV，并与从哈梅林长尾猴、赤猴和绿猴分离出的其他SFV进行比较。通过蛋白质免疫印迹分析，在所有SFV中均检测到了gag前体蛋白（p74/p70）。此外，通过扁豆凝集素结合和放射免疫沉淀法（RIPA）检测发现，来自绿猴分离株（SFV-Agm2）的包膜糖蛋白在大小上与env前体gp130、外部糖蛋白（gp70）和跨膜蛋白（gp48）相当。对每个SFV的pol和LTR区域的PCR扩增产物进行分子比较，结果表明狒狒SFV之间关系密切，而来自赤猴、哈梅林长尾猴和绿猴的SFV聚集在一起。狒狒病毒在LTR区域彼此之间仅相差4%；然而，与其他非洲猴SFV相比，差异高达26%。为了确定我们狒狒群体中SFV-Bab的流行率，我们采用了蛋白质免疫印迹法和PCR分析。在10只幼崽中有7只检测到针对SFV gag前体蛋白的抗体；然而，PCR检测均为阴性，这表明这些幼崽病毒呈阴性，其抗体源自母体。只有一只幼年狒狒（1/10）和所有成年狒狒（38/38）感染了SFV。综合这些结果表明，SFV随着其自然宿主的进化而产生并分化。此外，成年狒狒中SFV的高流行率强烈表明其传播途径为性传播或经口传播。
