Navigation Links
Rare case explains why some infected with HIV remain symptom free without antiretroviral drugs
Date:8/11/2008

AIDS experts at Johns Hopkins say they have compelling evidence that some people with HIV who for years and even decades show extremely low levels of the virus in their blood never progress to full-blown AIDS and remain symptom free even without treatment, probably do so because of the strength of their immune systems, not any defects in the strain of HIV that infected them in the first place.

Their conclusions about so-called elite suppressors, published this month in the Journal of Virology, come from rigorous blood and genetic studies from a monogamous, married, African-American couple in Baltimore, in which the wife was infected through sex with her husband more than a decade ago.

Unlike her husband, the wife remains symptom free, has consistently had viral counts of fewer than 50 copies per cubic milliliter of blood, and has not needed any treatment to keep the disease in check. The husband, as a so-called progressor, takes a potent drug cocktail to keep his infection from developing into full-blown AIDS, as demonstrated by viral counts in the hundreds of thousands per cubic milliliter of blood. The couple has been married for two decades and the husband was an intravenous drug user.

The scientists say the case study disproves some suspect theories about elite suppression that suggest it always involves a defective or "weakened" viral strain, which is easier for the immune system to attack, or that genetic variants confer a protective effect in suppressors.

"This is an extremely rare case of co-infection in a controlled, monogamous relationship, which showed us how a strong immune system in the elite suppressor kept the virus from replicating and infecting other cells," says senior study investigator and infectious disease specialist Joel Blankson, M.D., Ph.D.

"Our findings offer hope to vaccine researchers because they reveal that the immune system's primary offense, known as CD8 killer T-cells, can effectively halt disease progression by a pathogenic form of HIV," says Blankson, an assistant professor at the Johns Hopkins University School of Medicine.

"Moreover, the strength of the immune response was not dependent on infection by a weakened form of the virus. And if we can harness the means by which these elite white blood cells stop the virus, then we can hopefully 'teach' or reprogram white blood cells in others to also target HIV," he says.

Included in the blood analysis was genetic testing which confirmed that both husband and wife were infected with the same pathogenic strain of HIV and ruled out the possibility that there were genetic deficiencies in the virus that infected the wife.

Genetic testing also confirmed that both husband and wife had an overactive strand of genetic material tied to gene HLA B57, found in previous studies to be more common in those whose HIV infection was suppressed or slowed.

"The presence of this genetic spot is a discordant result that strongly contradicts theories that various genetic factors alone play a protective role in suppression," says Blankson.

He notes that study findings revealed a beneficial side effect to spurring the immune system cells to attack HIV.

Using new laboratory tests that precisely measure the immune response to various strains of HIV, researchers first tested T-cells from both the wife and husband to see if their immune system cells suppressed viral replication. They found that activated T-cells from the wife stalled HIV replication by as much as 90 percent, while the husband's T-cells stopped it by only 30 percent.

In subsequent genetic analyses, the viral strain in the wife's blood was found to have at least two mutations known to weaken the virus, while the viral strain in the husband's blood had fewer mutations affecting fitness.

According to Blankson, the stronger immune system in elite suppression not only lowers the viral count in the body, but also exerts selective, evolutionary pressure on the original strain of HIV to mutate away from the strong version that initially infected the couple, and towards weaker, less-fit forms.

"Elite suppression offers clues to vaccine researchers on many fronts: how CD8 killer T-cells can attack HIV and how a stronger immune response can force HIV into a permanent defensive state," says Blankson.

Antibody-based HIV vaccines have generally failed to work, and Blankson says, a new approach is needed and may be based on T-cell action.

He also plans to study differences in CD8 T-cells in elite suppressors and progressors, with the goal of retooling and activating T-cell action in progressors to act more like those in elite suppressors.


'/>"/>

Contact: David March
dmarch1@jhmi.edu
410-955-1534
Johns Hopkins Medical Institutions
Source:Eurekalert

Related medicine news :

1. Study Explains How Cranberries Prevent Urinary Infections
2. Fat Grafting Provides Permanent, Natural Looking Results - Dr. Michael Law Explains Fat Injections as a New Trend in Facial Plastic Surgery
3. Bestselling Author Dr. Timothy Brantley Explains the Connection of Food and Mood
4. Fact Sheet Explains Cleaners, Disinfectants
5. New Resource Explains What Seniors Can Do if Medicare Denies Coverage of Their Medicines
6. Study finds circumcision safe in both HIV-infected and HIV-uninfected men
7. Spectranetics Introduces New Device for Removal of Non-Functional and Infected Cardiac Leads
8. Some Facelift Patients Infected With MRSA Superbug
9. What are the predominant bacilli in the intestines ducklings infected with S. enteritidis?
10. Vicriviroc Demonstrates Potent and Sustained Viral Suppression Through 48 Weeks of Therapy in Treatment-Experienced HIV-Infected Patients
11. Antidepressants Help HIV-Infected Patients Stick to Treatment
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/25/2016)... ... ... "With 30 hand-drawn hand gesture animations, FCPX users can easily customize each ... Film Studios. , ProHand Cartoon’s package transforms over 1,300 hand-drawn pictures into hand ... select a ProHand generator and drag it above media or text in the Final ...
(Date:6/25/2016)... ... June 25, 2016 , ... On Friday, June 10, Van Mitchell, Secretary ... Work award to iHire in recognition of their exemplary accomplishments in worksite health promotion. ... Maryland Workplace Health & Wellness Symposium at the BWI Marriott in Linthicum Heights. iHire ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... June 19, ... the dangers associated with chronic pain and the benefits of holistic treatments, Serenity ... who are suffering with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a ...
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. Amanda ... orthodontic treatment. Dr. Cheng has extensive experience with all areas of orthodontics, including ... accelerated osteogenic orthodontics. , Micro-osteoperforation is a revolutionary adjunct to orthodontic treatment. ...
(Date:6/24/2016)... Norcross, Georgia (PRWEB) , ... June 24, 2016 ... ... Year” awards today at the Clinical Decision Making in Emergency Medicine conference in ... who have authored journal articles published in Emergency Medicine Practice and ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Roche (SIX: RO, ROG; ... for its Elecsys BRAHMS PCT (procalcitonin) assay as a ... septic shock. With this clearance, Roche is the first ... integrated solution for sepsis risk assessment and management. ... infection and PCT levels in blood can aid clinicians ...
(Date:6/23/2016)... 23, 2016 Research and Markets has ... 52" report to their offering. ... creates a favourable commercial environment for MedImmune to enter. The ... that will serve to drive considerable growth for effective anti-influenza ... to cap sales considerably, but development is still in its ...
(Date:6/23/2016)... INDIANAPOLIS , June 23, 2016 If ... Leaders Scholarship is any indication, the future is in ... at www.diabetesscholars.org by the Diabetes Scholars Foundation ... the way of academic and community service excellence. ... since 2012, and continues to advocate for people with ...
Breaking Medicine Technology: