Available Technology
Vaccination against HIV using Herpesvirus
Technology:
Novel vaccine strategy
Markets Addressed
Development of vaccine immunogens capable of eliciting protective immunity responses against HIV is proving to be an extremely difficult task. The most promising vaccine approaches have provided little or no protection in rhesus monkeys against challenge by the close relative of HIV, SIV. In addition, there have been no successful phase III trials of vaccine products against HIV.
There is a clear need for an HIV vaccine, as no good one currently exists. Much research is being done on HIV vaccines, using various vectors such as canarypox, attenuated Salmonella, or weakened adenovirus. However, clinical trials are still ongoing, and tests in model animals have only demonstrated partial protection. A vector providing greater protection over a long period of time is needed.
Using recombinant HHV-8 as a novel vaccine approach to protect humans against HIV/AIDS would greatly affect worldwide health if it works. An HIV vaccine is commonly considered the only way to stop the AIDS pandemic, as it will prevent further spread of the virus.
This invention could also be generalized to design treatments against other viral diseases. If a herpesvirus of choice is modified with viral antigens from other diseases, and this recombinant virus can trigger an immune response, this invention could be used as a vaccine for those diseases as well.
Innovations and Advantages
HIV and AIDS have been studied for over twenty years, but there is still no vaccine or cure. There are many populations around the globe that are highly vulnerable to HIV, and a vaccine to prevent further spread of HIV is greatly needed. Solutions currently being tested have given monkeys little to no protection against simian immunodeficiency virus (SIV).
Recombinant gamma herpesviruses are known to be useful vectors for delivering viral antigens. They have a number of beneficial characteristics, including (1) they have large double-stranded DNA genomes with many non-essential sites where transgenes can be introduced without viral inactivation; (2) they are diverse family from which one can choose the most appropriate host virus, and a tendency to cause persistent, life-long infection; (3) they target B cells, making them an attractive choice for diseases that target the immune system; and (4) they can be engineered to express viral antigens from transgenes integrated in their genomes.
The inventors demonstrated that it is possible to use recombinant gamma herpesviruses to express SIV antigens in rhesus monkeys and that these antigens trigger an immune response in the inoculated monkeys. More specifically, they demonstrated that the rhesus monkey rhadinovirus (RRV), a gamma-2 herpesvirus of rhesus monkeys that is closely related to the human herpesvirus-8, HHV-8, can be engineered to express specific SIV antigens.
Testing in primates demonstrates that inoculation with this RRV-SIV recombinant virus elicits potent immune responses to the foreign viral antigens, and persistent expression of anti-SIV antibodies against the envelope glycoprotein. Most importantly, this recombinant RRV has provided potent protection against AIDS in monkeys following challenge with SIV. In addition, further developments are in progress, including the addition of components that are known to enhance antibody dependent cell-mediated cytotoxicity.
If this novel vaccine strategy can be extended to human herpesviruses modified with HIV antigens, this could lead to a new HIV vaccine. A functional HIV vaccine in humans would be a great advantage over currently available treatments, which do not offer 100% protection against the virus.
Additional Information
Intellectual Property Status: Patent(s) pending
This technology is available for international licensing.
Tweet
Inventor(s):
Bilello, John P.
Desrosiers, Ronald C.
Categories:
For further information, please contact:
Michal Preminger, Director of Business Development
(617) 432-0920
Reference Harvard Case #2858