New HIV model may help in finding T cells that can fight against the virus

Chinese researches have recently developed a new HIV model in hopes of incorporating HIV’s behavioral dynamics into the modeling system. This new model suggests that a particular type of T cell could be useful in fighting HIV in a vaccine. Scientists from Xiamen University have been able to incorporate the ways HIV responds to antibodies, and its random mutations, into their model. This new model is able to act like the actual HIV virus does in real life.

(The structure of HIV)

In the past, clinical trials have shown that in the acute first phase of human infection (about 2-6 after the virus enters the host body), HIV behaves normally. Our body sends T Cells to fight the virus, which is growing stronger. T cells work when they are activated by the presence of their specific pathogen in the body. They have markers on the outside of their cells that bind to an antigen that is only on the HIV virus. They then begin to reproduce and go to the part of the body that is infected, where they begin to attack the virus. This is different from how the innate immune system works in that T cells are not only limited to attacking the virus when it is in the blood stream, since they can also kill infected cells, killing the virus before it can produce more viruses in that infected cell.

(A T cell attacking a virus)

In most viruses, T cells are able to completely fight off the virus and use their memory to patrol the bloodstream in case the virus ever comes back, in which case they would be able to recognize the virus immediately and fight it off again. However, in HIV, the T Cells are not able to completely kill the virus, which stores itself away and spends years recuperating its strength. HIV has the ability to target CD4+ T cells, which are the master regulators of our immune system. They also have many mutating properties. Researchers believe that these two factors are what allow HIV to escape total annihilation. During the time HIV hides and regains strength, it is also slowly attacking our immune system.

However, the body has CD8+ T cells. Until this new HIV model, scientists had never seen a simulation which includes how the CD8+ T cells could fight in the battle against HIV. CD8+ T cells may be able to provoke a stronger response against HIV because they are not targeted by the virus like our CD4+ T cells are. They also appear to be more able to put the virus down during the first acute phase of the infection in the initial 2-6 weeks. By putting these particular T cells into an AIDS vaccine, we may have gotten one step closer in being able to fight off the HIV virus.

-Emma G.

Sources:
http://www.medicalnewstoday.com/articles/187222.php
http://www.sciencemuseum.org.uk/on-line/lifecycle/images/1-2-5-3-5-2-2-0-0-0-0.jpg
http://biology.kenyon.edu/slonc/gene-web/Lentiviral/hiv_image.jpg