Featured Research

from universities, journals, and other organizations

New monkey model for AIDS offers promise for medical research

Date:
June 19, 2014
Source:
Rockefeller University
Summary:
HIV-1, the virus responsible for most cases of AIDS, is a very selective virus and does not readily infect species other than its usual hosts -- humans and chimpanzees -- making the search for effective treatments and vaccines for AIDS that much more difficult. In new scientific work, researchers have coaxed a slightly modified form of the HIV-1 virus to not only infect pigtailed macaques, a species of monkey, but to cause full blown AIDS in the primates, a first.

Unresistant. As part of the disease, human AIDS patients lose immune cells known as CD4+ T-cells. To develop a new animal model to study the disease, scientists induced AIDS from HIV-1 infection in otherwise resistant monkeys. Before infection (top), monkey CD4+ T-cells (brown) appear at normal levels. After 20 weeks of infection (bottom), these cells are almost completely absent.
Credit: Image courtesy of Rockefeller University

HIV-1, the virus responsible for most cases of AIDS, is a very selective virus. It does not readily infect species other than its usual hosts -- humans and chimpanzees. While this would qualify as good news for most mammals, for humans this fact has made the search for effective treatments and vaccines for AIDS that much more difficult; without an accurate animal model of the disease, researchers have had few options for clinical studies of the virus.

New work from Paul Bieniasz's Laboratory of Retrovirology at The Rockefeller University and the Aaron Diamond AIDS Research Center and Theodora Hatziioannou's laboratory, also at Aaron Diamond, may help fill this gap. In research described in Science, they announce that they have coaxed a slightly modified form of the HIV-1 virus to not only infect pigtailed macaques, a species of monkey, but to cause full blown AIDS in the primates, a first.

As part of the disease, human AIDS patients lose immune cells known as CD4+ T-cells. To develop a new animal model to study the disease, scientists induced AIDS from HIV-1 infection in otherwise resistant monkeys. Before infection (top), monkey CD4+ T-cells (brown) appear at normal levels. After 20 weeks of infection (bottom), these cells are almost completely absent.

"HIV-1 only causes AIDS in humans and chimpanzees, but the latter are not a practical model and are no longer used for HIV/AIDS research. Our goal has been to figure out how HIV-1 could cause disease in a new host," Bieniasz says. "By accomplishing this with macaques, we have taken a step toward establishing a new model for AIDS that can be used universally in prevention and treatment research."

Although pigtailed macaques have fewer defenses against HIV-1 than most other primates -- they lack an antiviral protein that fights off the virus -- the researchers still had to alter both the virus and the macaque immune system in order to induce AIDS.

They bolstered the virus with a defense-disabling protein made by Simian Immunodeficiency Virus (SIV), a relative of HIV-1. Then they encouraged the modified HIV strain to adapt to its new host by passing it from one monkey to another, resulting in six generations of infected monkeys and an adapted virus. Even so, the monkeys' immune systems were still able to control the HIV-1 infection. So, the researchers temporarily weakened their immune systems by depleting a type of white blood cell, known as a CD8 T-cell, that destroys virus-infected cells.

"When we depleted their CD8 cells, the infected monkeys developed disease closely mirroring that of human patients. For example they contracted AIDS-defining conditions including pneumocystis pneumonia, a textbook example of an opportunistic infection in AIDS," says Hatziioannou. "Because it replicates what happens when HIV-1 compromises a human patient's immune system, our approach could potentially be used in the development of therapies and preventative measures for human patients."

In fact, if fully developed, the macaque model will offer a substantial improvement for research. Often, HIV therapy and prevention research relies on SIV, a viral relative of HIV-1, since SIV can cause AIDS-like disease in nonhuman primates. However, SIV doesn't always behave the same way HIV-1 does. "We still have one major hurdle to overcome: If we could get HIV-1 to cause AIDS without depleting the CD8 cells, we could replace models that make use of SIV for this research."

This work and previous research in the lab has also illuminated the process by which HIV-1 and other members of the lentivirus family can colonize a new host like the macaques. It turns out that evading or fighting off the antiviral proteins produced by the new host's cells is key.

"This new model for HIV-1 infection is the result of years spent exploring scientific questions about how the virus interacts with a host's antiviral defenses. These kinds of basic insights will enable us to continue to improve this model," Hatziioannou says.


Story Source:

The above story is based on materials provided by Rockefeller University. Note: Materials may be edited for content and length.


Journal Reference:

  1. T. Hatziioannou, G. Q. Del Prete, B. F. Keele, J. D. Estes, M. W. McNatt, J. Bitzegeio, A. Raymond, A. Rodriguez, F. Schmidt, C. Mac Trubey, J. Smedley, M. Piatak, V. N. KewalRamani, J. D. Lifson, P. D. Bieniasz. HIV-1-induced AIDS in monkeys. Science, 2014; 344 (6190): 1401 DOI: 10.1126/science.1250761

Cite This Page:

Rockefeller University. "New monkey model for AIDS offers promise for medical research." ScienceDaily. ScienceDaily, 19 June 2014. <www.sciencedaily.com/releases/2014/06/140619153920.htm>.
Rockefeller University. (2014, June 19). New monkey model for AIDS offers promise for medical research. ScienceDaily. Retrieved October 2, 2014 from www.sciencedaily.com/releases/2014/06/140619153920.htm
Rockefeller University. "New monkey model for AIDS offers promise for medical research." ScienceDaily. www.sciencedaily.com/releases/2014/06/140619153920.htm (accessed October 2, 2014).

Share This



More Health & Medicine News

Thursday, October 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Pregnancy Spacing Could Have Big Impact On Autism Risks

Pregnancy Spacing Could Have Big Impact On Autism Risks

Newsy (Oct. 1, 2014) A new study says children born less than one year and more than five years after a sibling can have an increased risk for autism. Video provided by Newsy
Powered by NewsLook.com
Ebola Patient Told Hospital He Was from Liberia

Ebola Patient Told Hospital He Was from Liberia

AP (Oct. 1, 2014) The first Ebola patient diagnosed in the U.S. initially went to a Dallas emergency room last week but was sent home, despite telling a nurse that he had been in disease-ravaged West Africa, the hospital acknowledged Wednesday. (Oct. 1) Video provided by AP
Powered by NewsLook.com
Robotic Hair Restoration

Robotic Hair Restoration

Ivanhoe (Oct. 1, 2014) A new robotic procedure is changing the way we transplant hair. The ARTAS robot leaves no linear scarring and provides more natural results. Video provided by Ivanhoe
Powered by NewsLook.com
Insertable Cardiac Monitor

Insertable Cardiac Monitor

Ivanhoe (Oct. 1, 2014) A heart monitor the size of a paperclip that can save your life. The “Reveal Linq” allows a doctor to monitor patients with A-Fib on a continuous basis for up to 3 years! Video provided by Ivanhoe
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins