Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New evidence: AIDS-like disease in wild chimpanzees

24.07.2009
Groundbreaking study from international research team includes University of Illinois and Lincoln Park Zoo scientists

An international consortium has found that wild chimpanzees naturally infected with Simian Immunodeficiency Viruses (SIV) – long thought to be harmless to the apes – can contract an AIDS-like syndrome and die as a result. The findings are published in the July 23 edition of the journal Nature.

Scientists have known that the AIDS virus, HIV-1, first entered the human population after transmission from chimpanzees. The precursor virus, SIV, has many different forms, most of which infect various African monkey species. While there are data for only a few of these species, all of the evidence so far has indicated that monkey SIVs are not pathogenic in their natural hosts.

"We all assumed that the same was true of SIV infection in chimpanzees, but that turns out not to be the case," said Dr. Beatrice Hahn, a professor of medicine at the University of Alabama at Birmingham, who led the investigation. "But of course chimps are not monkeys. Chimpanzees and humans are very similar genetically, so perhaps we should not be surprised that these closely related viruses cause disease in both hosts."

The study focused on chimpanzees at Gombe National Park, on the shores of Lake Tanganyika in Tanzania. For nearly 50 years, primatologist Jane Goodall and her colleagues have studied the chimpanzee communities at Gombe, monitoring their biology and behavior.

Lincoln Park Zoo and University of Illinois researchers, in cooperation with the Jane Goodall Institute (JGI) and Tanzania National Parks (TANAPA), established a chimpanzee health-monitoring program at Gombe. This program provided the necessary field laboratories and veterinary expertise to enable post-mortem analyses of chimpanzees that died during the course of the study.

"We are pleased to see the groundbreaking results coming out of the multidisciplinary epidemiological health monitoring system we've established in Gombe," said veterinary epidemiologist Dominic Travis, vice president of conservation and science at Lincoln Park Zoo and an author on the study. "This has significance for Gombe chimp health and park management, disease ecology as it relates to retroviral emergence, and to ape conservation as a whole by using Gombe as a laboratory. This field site is once again a model of how long-term scientific studies can inform us in many ways."

For the last nine years, the consortium has been monitoring the SIV infection status of the Gombe chimpanzees. It was possible to determine from fecal samples which individuals were infected at the start of the study, and which became infected during the study. At any one time during this period, between 10 and 20 percent of chimpanzees were SIV-positive. Statistical death hazard analyses, taking into account factors such as an individual's age and sex, indicated that those chimpanzees infected with SIV were 10 to16 times more likely to die in any year than those who remained uninfected.

According to anthropology professor Jamie Holland Jones of Stanford University, who performed the analyses, "at this point we cannot be too precise about the magnitude of the effect, because the number of chimpanzees surveyed is still limited. Nevertheless, the evidence is clear that infected apes have lower survival rates."

The consortium also found that infected females were significantly less likely to give birth, and that any infants born to infected mothers had a low chance of survival.

Additional evidence came from necropsies performed by veterinary pathologists from the University of Illinois Zoological Pathology Program. A hallmark of HIV-1 infection in humans is the loss of CD4+ T-cells; these cells are a vital component of the immune system, and their depletion renders patients susceptible to many other infections – the classic symptoms of AIDS.

"When I first looked at these samples I was taken aback," said University of Illinois veterinary pathologist Karen Terio, a primary author on the paper. "Slides from one of the chimps showed extreme lymphatic tissue destruction, and looked just like a sample from a human patient who has died of AIDS."

Analysis by Jake Estes, an investigator at the National Cancer Institute and a primary author on the paper, confirmed a link between SIV infection and CD4+ T-cell decline in the chimpanzees.

Although this study was limited to chimpanzees at Gombe, SIV infection is widespread across two subspecies, central and eastern chimpanzees, which range from Cameroon in west central Africa to Tanzania in the east. (Two other subspecies, western and Nigerian chimpanzees, do not appear to have SIV infections.)

"Previously, we didn't think SIV could affect chimpanzee population health. Now we know it's possible," said primatologist Elizabeth Lonsdorf from Lincoln Park Zoo, a co-primary investigator of the zoo-led health monitoring initiative. "The next step is to understand this issue better in Gombe to see if it is site-specific, or if it has potential widespread implications for chimpanzee conservation."

The finding that SIV causes disease in chimpanzees opens up a number of new avenues of research.

The international consortium comprises researchers from Gombe Stream Research Centre, The Jane Goodall Institute, Lincoln Park Zoo, National Cancer Institute, Stanford University, Tanzania National Parks, University of Alabama at Birmingham, University of Edinburgh, University of Illinois, University of Minnesota, University of Pennsylvania and Yerkes National Primate Research Centre.

ABOUT LINCOLN PARK ZOO

Lincoln Park Zoo, a historic Chicago landmark founded in 1868, is dedicated to connecting people with nature by providing a free, family-oriented wildlife experience. A leader in conservation science both globally and locally, the zoo exemplifies the highest quality animal care and educational outreach. The not-for-profit zoo, managed by The Lincoln Park Zoological Society, is a member-supported organization and one of the nation's only free, privately managed zoos. For more information, call 312 -742-2000 or visit www.lpzoo.org.

For more information about the University of Illinois News Bureau, call 217-333-1085 or visit http://news.illinois.edu.

Diana Yates | University of Illinois
Further information:
http://www.illinois.edu

Further reports about: Aids CD4+ Cancer HIV-1 Illinois River Watershed SIV T-cell Tanzania

More articles from Life Sciences:

nachricht Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

nachricht Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017
25.04.2017 | Laser Zentrum Hannover e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA examines newly formed Tropical Depression 3W in 3-D

26.04.2017 | Earth Sciences

New High-Performance Center Translational Medical Engineering

26.04.2017 | Health and Medicine

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>