ScienceDaily (July 23, 2009)

尽管AIDS病毒（HIV-1）从黑猩猩中传入人群中，科学家们长期以来一直认为黑猩猩并不会发展为AIDS。但是，一个包括明尼苏达大学教授 Anne Pusey 和 Michael Wilson的国际性团队的一项新研究表明，感染了SIV（猿类免疫缺陷性病毒，HIV-1的前体）的黑猩猩也会感染并死于AIDS。这项发现发表在7月23日的 Nature期刊上。

据作者们报道，其研究组群中被感染的黑猩猩与那些未感染的相比死亡率大约在10-16倍左右。研究组还发现雌性感染者生育机率更低，且被感染母体产下的婴儿存活率低。他们了解到这种病毒可通过性渠道和母乳传播。在过去的九年研究期间，94头黑猩猩中的感染率约为百分之10-20。这项发现为新的研究机会打开了大门。

“我们希望这能够带来对病毒的更好认识，这将同时使人类和黑猩猩受益，”Jane Goodall 说。她的注意力在最近几年间从研究转向了黑猩猩及其栖息地的保护。

这项研究集中在Tanzania的Gombe国家公园，Goodall和她的同事们在此已经对黑猩猩进行了接近50年的研究。研究者们使用的数据来自Goodall的一个长期合作伙伴Pusey在明尼苏达大学的灵长类研究中心的存档。这被用于理解SIV如何在黑猩猩中传播及病毒如何对黑猩猩的生存和繁殖造成影响。

阿拉巴马大学的病毒学家Beatrice Hahn 领导了这项涉及Pusey及其同事们的自然研究。Hahn\'s实验室的Brandon Keele 和 Rebecca Rudicell使用了他们开发的技术以测定黑猩猩排泄物样本中的SIV病毒。样本由在Gombe的研究者收集，并运往阿拉巴马进行分析。

对死亡黑猩猩组织样本的检测显示在SIV感染个体中存在CD4+ T细胞（此细胞对免疫起重要作用）损耗。它们的损耗使得受害者易于受到许多种其他感染——即AIDS的传统表现。

Wilson组织了一支由坦桑尼亚和美国专家组成的队伍以指导第一次对于一体死于AIDS的黑猩猩的死后检测。

“从科学角度来看，这些病毒以和对人类如此相似的方式影响黑猩猩实在令人着迷，”Wilson说，“但是依然存在困难，我们无法给予那些生命可能由于病毒而缩短的人们太多帮助。”Wilson是一位拥有人类学和生态、进化与行为学双学位的 Land-Grant 荣誉教授。

“治愈SIV感染的黑猩猩还不现实，但是有迹象显示SIV对于黑猩猩并不像HIV-1对于人类那么具有致病性。”学院的生物学院生态、进化与行为学系卓越的荣誉教授Pusey说，“到目前为止，即使存在疾病导致的死亡，主要研究对象群体依然保持着其规模。

Chimpanzees Infected With SIV Do Develop And Die From AIDS, Contrary To Prevailing View

ScienceDaily (July 23, 2009) — Although the AIDS virus (HIV-1) entered the human population through chimpanzees, scientists have long believed that chimpanzees don\'t develop AIDS. But a new study from an international team, including University of Minnesota professors Anne Pusey and Michael Wilson, shows that chimpanzees infected with SIV (simian immunodeficiency virus), the precursor to HIV-1, do contract and die from AIDS. The discovery is published in the July 23 issue of Nature.

The authors report that infected chimpanzees in their study group were 10-16 times more likely to die than those who were uninfected. The team also found that infected females were less likely to give birth and infants born to infected mothers were unlikely to survive. The virus, they learned, was transmitted sexually and through mother\'s milk. Over the nine-year study period, 10-20 percent of the 94 chimpanzees were infected at any one time.

The finding opens up new opportunities for research.

"We hope this will lead to a better understanding of the virus that will benefit both humans and chimpanzees," said Jane Goodall, whose focus has shifted in recent years from research to conservation of chimpanzees and their habitats.

The study focused on chimpanzees at Gombe National Park, Tanzania, where Goodall and her colleagues have studied chimpanzees for nearly 50 years. Researchers used data that Pusey, a long-time associate of Goodall\'s, archived at the Jane Goodall Institute\'s Center for Primate Studies at the University of Minnesota, to understand how SIV is transmitted among chimpanzees, and how the virus affects chimpanzee survival and reproduction.

Virologist Beatrice Hahn at the University of Alabama led the Nature study, which involved Pusey and her colleagues. Brandon Keele and Rebecca Rudicell in Hahn\'s lab used techniques they developed to detect SIV in chimpanzee fecal samples. Samples were collected by research staff at Gombe and shipped to Alabama for analysis.

Examination of tissue samples from dead chimpanzees revealed a loss of CD4+ T cells (which are vital to immunity) in SIV-infected chimpanzees. Loss of these cells renders victims susceptible to many other infections – the classic indication of AIDS. Wilson organized a team of Tanzanian and American specialists to conduct the first post-mortem exam of a chimpanzee that died from AIDS.

"From a scientific perspective, it is fascinating to learn that the virus affects chimpanzees in similar ways to humans," Wilson said. "But it is difficult knowing that there isn\'t much we can do to help those whose lives may be shortened by the virus." Wilson is a McKnight Land-Grant Professor with a joint appointment in Anthropology and Ecology, Evolution and Behavior.

"It isn\'t practical to treat the chimpanzees for SIV infections, but it appears that SIV in chimpanzees is not quite as pathogenic as HIV-1 in humans," said Pusey, who is a Distinguished McKnight University Professor in the College of Biological Sciences Department of Ecology, Evolution and Behavior. "So far, the main study community has maintained its size despite mortality from diseases."