Scientists Find Vaccine That Completely Blocks HIV Infection in Monkeys
August 30, 2014
Evolution and Biology, News
Original link: http://www.fromquarkstoquasars.com/scientists-find-vaccine-that-completely-blocks-hiv-infection-in-monkeys/
Original link: http://www.fromquarkstoquasars.com/scientists-find-vaccine-that-completely-blocks-hiv-infection-in-monkeys/
Image of an HIV cell. Via WHO (World Health Organization)
The battle against HIV and AIDS continues. The virus that causes these conditions has wreaked havoc on millions of lives. The World Health Organization estimates that, in 2011 alone, some 1.7 million people died of HIV/AIDS related illnesses. Although the life expectancy for individuals with this virus was initially extremely short, in recent years the drugs that are used to combat this condition have improved greatly, allowing individuals with the virus to live without too much pain or duress for decades.
However, these drugs are not cures. They treat the condition by essentially keeping HIV replication at a minimum, and the drugs must be taken for life or the HIV will proliferate and spread. Thus, they do not cure the patient. That said, in the past few years we have progressed by leaps and bounds, making amazing new headway in the fight against HIV and AIDS.
Now, according to recently published research, a new oral vaccine has been found to completely stop rhesus macaque monkeys from being infected with simian immunodeficiency virus (SIV, which is the monkey equivalent of HIV). In the paper, published in Frontiers in Immunology, the scientists note that this vaccine works by suppressing an immune response.
In order to function and proliferate (spread), HIV and SIV require immune cells that are known as CD4 T-cells. The new vaccine works by effectively removing the CD4 T-cells from the equation.
Ultimately, this new treatment focuses on stimulating the production of CD8 T-cells, which prevents the monkeys’ CD4 cells from recognizing SIV, which (in turn) prevents an immune response and stops SIV from hijacking the CD4 cells and spreading throughout the body.
Most vaccines work in an entirely different fashion—by actively causing an immune response. This treatment, as mentioned above, works precisely because it suppresses any such response.
The vaccine essentially consists of inactivated SIV that is given alongside doses of bacteria that are familiar and recognized as “friendly” by the body. The effectiveness of this treatment is surprising and unexpected because, when the inactive SIV is administered to an organism on its own, it triggers a normal immune response. The researchers are still working to understand why giving inactivated SIV alongside a probiotic produces such a strong immune-suppressing result.
Regardless, to date, all 15 monkeys that were given the vaccine orally have been completely protected against SIV infection. Moreover, the vaccinated monkeys are still able to suppress viral reproduction four years after vaccination. As such, the researchers are now planning to research whether or not this same method would be effective in humans. Two initial safety trials are now planned in humans both in HIV-negative and HIV-positive volunteers.
This new development comes at an appropriate time, as reports this week confirmed that the “Mississippi baby,” a child believed to have been functionally cured of HIV, was found to have the virus once again.
Of course, other methods have looked promising, but ultimately been ineffective when used in humans. The scheduled trials will, hopefully, yield promising results.
