Navigation Links
Novel Vaccine Approach Offers Hope in Fight Against HIV
Date:5/17/2009

--Gene Transfer Technology May Lead to an HIV Vaccine--

PHILADELPHIA, May 17 /PRNewswire-USNewswire/ -- A research team may have broken the stubborn impasse that has frustrated the invention of an effective HIV vaccine, by using an approach that bypasses the usual path followed by vaccine developers. By using gene transfer technology that produces molecules that block infection, the scientists protected monkeys from infection by a virus closely related to HIV -- the simian immunodeficiency virus, or SIV -- that causes AIDS in rhesus monkeys.

"We used a leapfrog strategy, bypassing the natural immune system response that was the target of all previous HIV and SIV vaccine candidates," said study leader Philip R. Johnson, M.D., chief scientific officer at The Children's Hospital of Philadelphia. Johnson developed the novel approach over a ten-year period, collaborating with K. Reed Clark, Ph.D., a molecular virologist at Nationwide Children's Hospital in Columbus, Ohio.

The study appeared today in the online version of Nature Medicine.

Johnson cautioned that many hurdles remain before the technique used in this animal study might be translated into an HIV vaccine for humans. If the technique leads to an effective HIV vaccine, such a vaccine may be years away from realization.

Most attempts at developing an HIV vaccine have used substances aimed at stimulating the body's immune system to produce antibodies or killer cells that would eliminate the virus before or after it infected cells in the body. However, clinical trials have been disappointing. HIV vaccines have not elicited protective immune responses, just as the body fails on its own to produce an effective response against HIV during natural HIV infection.

The approach taken in the current study was divided into two phases. In the first phase, the research team created antibody-like proteins (called immunoadhesins) that were specifically designed to bind to SIV and block it from infecting cells. Once proven to work against SIV in the laboratory, DNA representing SIV-specific immunoadhesins was engineered into a carrier virus designed to deliver the DNA to monkeys. The researchers chose adeno-associated virus (AAV) as the carrier virus because it is a very effective way to insert DNA into the cells of a monkey or human.

In the second part of the study, the team injected AAV carriers into the muscles of monkeys, where the imported DNA produced immunoadhesins that entered the blood circulation. One month after administration of the AAV carriers, the immunized monkeys were injected with live, AIDS-causing SIV. The majority of the immunized monkeys were completely protected from SIV infection, and all were protected from AIDS. In contrast, a group of unimmunized monkeys were all infected by SIV, and two-thirds died of AIDS complications. High concentrations of the SIV-specific immunoadhesins remained in the blood for over a year.

Further studies need to be conducted if this technique is to become an actual preventive measure against HIV infection in people, Johnson said. "To ultimately succeed, more and better molecules that work against HIV, including human monoclonal antibodies, will be needed," he and his co-authors conclude. Finally, added Johnson, their approach may also have potential use in preventing other infectious diseases, such as malaria.

Grants from the National Institute of Allergic and Infectious Diseases of the National Institutes of Health supported this study. Johnson's collaborators, in addition to Clark, were Jianchao Zhang, of Nationwide Children's Hospital, Columbus, Ohio; Eloisa Yuste and Ronald C. Desrosiers of the New England Primate Research Center and Harvard Medical School; and Bruce C. Schnepp, Mary J. Connell, and Sean M. Greene, of Children's Hospital and the University of Pennsylvania School of Medicine. Johnson also is on the University of Pennsylvania faculty.

Johnson et al, "Vector-mediated gene transfer engenders long-lived neutralizing activity and protection against SIV infection in monkeys," Nature Medicine, published online May 17, 2009. (http://dx.doi.org/10.1038/nm.1967)

About The Children's Hospital of Philadelphia

The Children's Hospital of Philadelphia was founded in 1855 as the nation's first pediatric hospital. Through its long-standing commitment to providing exceptional patient care, training new generations of pediatric healthcare professionals and pioneering major research initiatives, Children's Hospital has fostered many discoveries that have benefited children worldwide. Its pediatric research program is among the largest in the country, ranking second in National Institutes of Health funding. In addition, its unique family-centered care and public service programs have brought the 430-bed hospital recognition as a leading advocate for children and adolescents. For more information, visit http://www.chop.edu.

    CONTACT: Juliann Walsh
    The Children's Hospital of Philadelphia
    Phone: (267) 426-6054
    WalshJ1@email.chop.edu


'/>"/>
SOURCE The Children's Hospital of Philadelphia
Copyright©2009 PR Newswire.
All rights reserved

Related medicine technology :

1. One Step Closer: Novel Opioid Receptor Compound in Phase I Clinical Trials
2. ImQuest BioSciences Receives Phase I SBIR Grant to Develop a Novel Hepatitis C Virus Therapeutic Agent
3. VentiRx Pharmaceuticals Initiates Phase I Clinical Trial of VTX-1463, a Novel TLR8 Agonist for the Treatment of Allergic Rhinitis
4. Pharmacyclics Initiates Phase 1 Clinical Trial of Novel Oral Btk Inhibitor for Refractory B-cell Non-Hodgkins Lymphoma
5. Watson Announces United States Availability of RAPAFLO(TM) (silodosin), a Novel New Treatment in Benign Prostatic Hyperplasia (BPH)
6. Rib-X Pharmaceuticals Novel Antibiotic Delafloxacin Named One of R&D Directions 100 Great Investigational Drugs of 2009
7. Worldwide Sensation: "A"- Implant Novelty From Austria
8. Novel Valortim(R) Mechanism of Action Data Presented at the Keystone Symposia on Molecular and Cellular Biology
9. Calixa Therapeutics Announces Positive Phase 1 Results for CXA-101, a Novel Intravenous Cephalosporin Antibiotic with Excellent Anti-Pseudomonal Activity
10. Hana Biosciences Announces Successful Planned Independent Safety Analysis Supports Ability to Complete Pivotal rALLy Clinical Trial of Marqibo, Its Lead Novel Anti-Cancer Compound
11. Novavax Reports Positive Preclinical Results for a Novel, Broadly Cross-Protective H5N1 Pandemic Influenza Virus-like Particle (VLP) Vaccine Candidate
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/11/2016)... F ast access to ... at the point of need   ... and services, has launched a ClinicalKey mobile app that enables ... Elsevier designed the mobile app to allow users to select access to ... Android and iOS formats for mobile phone and tablet. ...
(Date:2/11/2016)... , Feb. 11, 2016 Scientists ... cell-isolation method that opens the door to genetic ... now have been impossible to isolate with 100 ... isolate specific tumor types in various stages of ... variants of these cells that are clinically relevant, ...
(Date:2/11/2016)... , Feb. 11, 2016  NanoViricides, Inc. ... it has entered into an agreement with the ... nanoviricides® drug candidates in standard animal models of ... , Research Director. Dr. Romanowski has extensive experience ... --> Eric Romanowski , Research ...
Breaking Medicine Technology:
(Date:2/10/2016)... (PRWEB) , ... February 10, 2016 , ... LaserShip, a ... water to the Food Bank of Eastern Michigan last Friday in order to aid ... footprint into the Midwest to include a facility located in Clio, only 15 miles ...
(Date:2/10/2016)... Walton Beach, Florida (PRWEB) , ... February 10, ... ... the innovative weather-forecasting company is unveiling its revolutionary new 2.0 version at the ... platform, MetLoop has “put the power of the world's most advanced weather technology ...
(Date:2/10/2016)... ... February 10, 2016 , ... Intermedix announced on ... Medicine , an emergency medicine professional association, to support the organization's newly established ... American Academy of Emergency Medicine, or AAEM, seeks to empower emergency physicians to ...
(Date:2/10/2016)... ... , ... Emergency rooms provide emergency care to stabilize critical health issues, but ... dental emergencies at risk of losing a tooth or their smiles. Dr. Marine Martirosyan, ... dental emergencies include:, , Avulsed or knocked-out teeth , ...
(Date:2/10/2016)... ... February 10, 2016 , ... Dr. Jessica Barron, of Barron Family ... new dental patients and families in the North Metro Denver area. The new dental ... to cosmetic dentistry, and all in the most relaxing environment. , While some dental ...
Breaking Medicine News(10 mins):