Navigation Links
Progress made in HIV vaccine development

Researchers have successfully tested two candidate vaccines that may eventually be used together to confer immunity against HIV infection. Their findings are published in the December 15 issue of The Journal of Infectious Diseases, now available online.

Barney S. Graham, MD, PhD, and colleagues from the National Institutes of Health IH Vaccine Research Center in Maryland, the Fred Hutchinson Cancer Research Center in Seattle, and GenVec Incorporated tested two possible HIV vaccines with the hope of producing an immune response in healthy, uninfected adults. One was a plasmid DNA-based vaccine expressing genes from three dominant HIV subtypes, and the second used recombinant adenovirus serotype 5 (rAd5) as a vector to deliver similar HIV strains.

"Both approaches operate by gene delivery of customized vaccine antigens that are produced by host cells to initiate an immune response. DNA is simple and does not have the problem of anti-vector immunity. However, DNA may be less potent than vector-based gene delivery strategies. Replication-defective rAd5 has the advantage of targeted, efficient gene delivery and high potency, but may be susceptible to anti-vector immunity," said Graham.

Both vaccines were tested in healthy uninfected adult volunteers. The DNA vaccine was found safe and well-tolerated. By week 12 following immunization, 97.5% of vaccinees experienced positive CD4 T cell responses and 40% experienced positive CD8 T cell responses.

The recombinant vector vaccine was also well-tolerated, but higher doses led to some adverse events such as pain and fever. By week 4 following immunization, 93.3% of vaccinees experienced positive CD4 T cell responses, and 60% experienced positive CD8 T cell responses.

"HIV-specific CD8 cell responses clear virus infected cells, and appear during the declining viremia following acute infection," explained Graham. "HIV-specific CD4 responses also peak early in infection; however this response diminishes soon after seroconversion. Maintenance of a functional HIV-specific CD4 T cell response correlates with long term non-progression of HIV disease."

Harriet L. Robinson, PhD, from Emory University and Kent J. Weinhold, PhD, from Duke University commented on the impact of these results in their accompanying editorial. "The DNA studies are a landmark for DNA-based vaccines in that they are the first to demonstrate a DNA vaccine successfully eliciting immune responses in essentially all vaccinated volunteers," they said. "The Ad5 recombinant HIV vaccine had both a higher percentage of responders and, overall, a higher magnitude of responses than the DNA vaccine."

The next step, according to Graham, is "to evaluate the combination of DNA priming and rAd5 boosting. Combining these distinct gene-delivery vaccination approaches has the potential to induce higher levels of T cell responses and a different quality of response than either approach by itself."

As Robinson and Weinhold add, the idea behind combining strategies is that "the vaccine uses DNA to prime the immune response and a replication defective recombinant adenovirus serotype 5 vector to boost responses."


'"/>

Source:Infectious Diseases Society of America


Related biology news :

1. Bevacizumab Combined With Chemotherapy Improves Progression-Free Survival for Patients With Advanced Breast Cancer
2. AIDS Public Awareness Campaign Expands Following Report Of Rapidly Progressive HIV
3. Progress on HIV/AIDS significant but insufficient
4. Progress being made in exploring potential use of stem cells to treat heart disease
5. Progress toward artificial photosynthesis?
6. Research advances quest for HIV-1 vaccine
7. A much-needed shot in the arm for HIV vaccine development
8. Discovery of key proteins shape could lead to improved bacterial pneumonia vaccine
9. Gene vaccine for Alzheimers disease shows promising results
10. Influenza vaccine uses insect cells to speed development
11. Norovirus, AIDS vaccine and Hepatitis Virus
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:12/5/2016)... WASHINGTON , Dec. 5, 2016  The ... (NIJ), today published "Can CT Scans Enhance or ... examines the potential of supporting or replacing forensic ... a CT scan. In response to ... NIJ is exploring using CT scans as a ...
(Date:12/2/2016)... 1, 2016 The report "Biometric ... Future Technology (Iris Recognition System), Vehicle Type (Passenger ... Forecast to 2021", published by MarketsandMarkets, the market ... 2016, and is projected to grow to USD ... 14.06%.      (Logo: http://photos.prnewswire.com/prnh/20160303/792302) ...
(Date:12/2/2016)...   SoftServe , a global digital technology ... electrocardiogram (ECG) biosensor analysis system for continuous driver ... The smart system ensures device-to-device communication between ECG ... mobile devices to easily ,recognize, and monitor users ... technology advances, so too must the security systems ...
Breaking Biology News(10 mins):
(Date:12/5/2016)... Dec. 5, 2016 Axovant Sciences Ltd. (NYSE: ... focused on the treatment of dementia, today announced that ... treatment of Alzheimer,s disease will be presented at the ... Friday, December 9, 2016 in San Diego ... of both simple and complex measures of activities of ...
(Date:12/5/2016)... Atlanta, Georgia (PRWEB) , ... December 05, 2016 ... ... hydrophobic, lignin-coated nanocellulose, including both cellulose nanocrystals and cellulose nanofibrils. The composition ... nanocellulose. There are also claims directed to combination with polymers, carbon fibers, ...
(Date:12/5/2016)... , Dec 5, 2016 Research and ... "Biomarkers - Technologies, Markets and Companies" to their offering. ... , , ... their discovery using various -omics technologies such as proteomics and metabolomics. ... new tests are also based on biomarker. Currently the ...
(Date:12/5/2016)... ... December 05, 2016 , ... The Real Dirt with ... cannabis technology and application experts, Chip Baker. Chip Baker formerly co-founded Royal Gold ... past 30 years, Chip Baker other industry veterans have made the evolution of ...
Breaking Biology Technology: