Featured Research

from universities, journals, and other organizations

Scientists Succeed In Blocking Transmission Of Cell-Associated AIDS Virus

Date:
January 17, 2002
Source:
Johns Hopkins University Bloomberg School Of Public Health
Summary:
Scientists at the Johns Hopkins Bloomberg School of Public Health and their colleagues have made a significant advance in understanding how to block the transmission of the AIDS virus from one sexual partner to another.

Scientists at the Johns Hopkins Bloomberg School of Public Health and their colleagues have made a significant advance in understanding how to block the transmission of the AIDS virus from one sexual partner to another.

They have developed a mouse model that allows them to identify and test agents that can stop the migration of white blood cells in semen or cervical mucus that are carrying the human immunodeficiency virus (HIV) nested within them. Using this animal model, the authors have already identified one compound that blocks this type of HIV transmission. The study appears in the January 2002 issue of the Journal of Clinical Investigation.

HIV is transmitted between sexual partners in two principal ways. First, by the "naked" virus itself when it enters the body of an uninfected sexual partner during intercourse. Until now, most efforts to prevent HIV transmission have focused on ways of killing naked, cell-free HIV, which, for example, can be eliminated by the antibodies generated by vaccines.

A second, less well known mode of transmission is by cell-associated viruses, viruses that hide inside normal white blood cells and are carried "Trojan horse-style" into the body. These cell-associated viruses may not be blocked by a vaccine that targets the naked virus.

First author Kristen Khanna, PhD, a research associate in the Department of Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health, notes, "While considerable effort has been directed toward the identification of intervention strategies such as vaccines directed against cell-free viruses, there has been little effort to identify strategies for interrupting the migration of cells that are infected with HIV. We know that such infected cells are present in semen and vaginal secretions of infected individuals and many studies suggest that cell-associated transmission of HIV may, in fact, be more efficient that transmission of cell-free virus. We believe that any successful intervention therapy against the AIDS virus should include a component that can block infected-cell migration into the sexual partner."

Efforts to block cell-associated HIV transmission have been stymied by the lack of an animal model that could mimic this type of transmission. In the present study, the researchers tell how they developed a mouse that is susceptible to the vaginal transmission of cell-associated HIV, but that is not susceptible to infection by cell-free virus.

"These animals," said Richard Markham, MD, a professor of Molecular Microbiology and Immunology at the Johns Hopkins Bloomberg School of Public Health and senior investigator on the studies, "allowed us to examine the process of cell-associated HIV-1 transmission in the absence of the possibility that cell-free viruses were also contributing to the infection."

Armed with their new animal model, the scientists were quickly able to identify a candidate agent that was highly effective in interrupting vaginal transmission of cell-associated HIV. The researchers focused on a cholesterol-depleting agent, beta-cyclodextrin (beta-CD), shown previously in the laboratory of co-author Dr. James Hildreth, an associate professor in the Department of Pharmacology, Johns Hopkins School of Medicine, to interfere with the ability of cell-free virus to establish infection. The authors found that application of beta-CD within the vagina of the mouse prior to inoculation with HIV-infected cells dramatically reduced transmission.

Moreover, beta-CD, a water-soluble carbohydrate sometimes used as a food additive, was substantially less toxic to the vaginal wall than the widely used spermicide nonoxynol-9. "Beta-cyclodextrin could therefore be a safe solution to the problem of infection by cell-associated HIV. It is particularly appealing because it offers a method of disease prevention that could be controlled by women," said Markham.

In summary, the authors state, "The current studies indicate that the mouse model of vaginal transmission of cell-associated virus provides a simple and inexpensive model to identify agents that may be necessary components of vaginal products for preventing the sexual transmission of HIV. These studies demonstrate that beta-CD significantly blocks vaginal transmission of cell-associated HIV-1 and warrants further study in the preclinical and clinical settings."


Story Source:

The above story is based on materials provided by Johns Hopkins University Bloomberg School Of Public Health. Note: Materials may be edited for content and length.


Cite This Page:

Johns Hopkins University Bloomberg School Of Public Health. "Scientists Succeed In Blocking Transmission Of Cell-Associated AIDS Virus." ScienceDaily. ScienceDaily, 17 January 2002. <www.sciencedaily.com/releases/2002/01/020117072648.htm>.
Johns Hopkins University Bloomberg School Of Public Health. (2002, January 17). Scientists Succeed In Blocking Transmission Of Cell-Associated AIDS Virus. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2002/01/020117072648.htm
Johns Hopkins University Bloomberg School Of Public Health. "Scientists Succeed In Blocking Transmission Of Cell-Associated AIDS Virus." ScienceDaily. www.sciencedaily.com/releases/2002/01/020117072648.htm (accessed July 25, 2014).

Share This




More Health & Medicine News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com
Condemned Man's US Execution Takes Nearly Two Hours

Condemned Man's US Execution Takes Nearly Two Hours

AFP (July 24, 2014) America's death penalty debate raged Thursday after it took nearly two hours for Arizona to execute a prisoner who lost a Supreme Court battle challenging the experimental lethal drug cocktail. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com
Can Watching TV Make You Feel Like A Failure?

Can Watching TV Make You Feel Like A Failure?

Newsy (July 24, 2014) A study by German researchers claims watching TV while you're stressed out can make you feel guilty and like a failure. Video provided by Newsy
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:
from the past week

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