New research done on monkeys and the HIV equivalent virus (Simian Immunodeficiency Virus) that affects the latter seems to be quite promising as it is being hailed as the potential primary steps to finally lead to the engineering of a vaccine for humans. A vaccine that has been observed to have positive effects on monkeys has been discovered. It has a relatively simple structure that could pave the way to the making of one to fight HIV in humans.
Simian Immunodeficiency Viruses (SIVs) are known to affect non-human primates such as chimpanzees. SIVs are, in fact, close relatives of HIV – their effect on the rhesus macaques is pathologically similar to the one HIV has on humans. Therefore, scientists have used SIV and rhesus monkeys as a model relating them to the human situation.
SIV and HIV work in similar ways: they both infect cells of the immune system, and replicate inside the latter. They infect CD4+ T cell preferentially. The more these specific cells are depleted, the more does one become vulnerable to contracting infections from other pathogens. When the macaques were given the new vaccine, they began manufacturing an unknown regulatory CD8 white blood cell which prevents the activation of infected CD4 cells. When this deactivation mechanism is tuned, the virus cannot replicate, and it is thus prevented from spreading inside the body of the monkeys.
The new vaccine consists of inactivated SIV and a cocktail of bacteria. The latter were taken from the gut; they are used in pro-biotic supplements.
Clinical trials are to be done to assess whether or not humans also produce a similar type of the unknown CD8 white blood cell. The next step from there would be to test HIV-positive patients.
What gives even more hope is that 15 of the 29 monkeys which were chosen as cobayes for the experiment seem to have developed complete protection from SIV.