HIV interacting with the immune system. Image: TCD
In our efforts to better understand how HIV escapes the effects of the immune system, scientists have discovered a new mechanism that could hold the answer.
Decades after it was first identified in humans, about 40m people worldwide are now believed to be infected with HIV, making it one of the greatest health issues globally. However, many elements of the virus remain a mystery.
One of the greatest mysteries is how HIV evades the immune system, thus requiring the use of new medication. While this can hold off the effects of the virus, it needs be taken for the rest of the patient’s life.
Now, new research conducted by a team from Trinity College Dublin (TCD) has revealed the mechanism that shows precisely how the virus avoids elimination.
The findings revealed that HIV targets a pathway involving a number of biological molecules that are key in blocking viral activity and clearing infection.
In any typical infection, our immune system produces a powerful molecule – known as an interferon – which disrupts the infection, breaking the virus’s ability to replicate.
The interferon activates an assembly line of molecules in our cells via the interferon signalling pathway, causing the body to make antivirals that help to clear the infection.
But when HIV enters the patient, the virus is not fully cleared, leading to TCD researchers investigating whether it somehow blocked the interferon signalling pathway and thus avoided the immune response that is designed to cure viral infection.
Alas, the research has proven this to be the case.
A paradigm shift
“We discovered that HIV promotes the destruction of the antiviral interferon signalling pathway,” said Nigel Stevenson, assistant professor in immunology at TCD.
“Essentially, HIV uses the machinery in our own cells to do this, and the virus is thus able to reduce the production of many important antiviral molecules. Without these antiviral molecules, our immune system can’t clear viral infections.”
Emphasising the discovery’s importance, Stevenson added: “Our new revelation sheds new light on how HIV avoids elimination, which in turn may explain why HIV is still not a curable disease.
“We feel this discovery could mark a paradigm shift in our understanding of how this virus evades our immune response. It should open the door to a new era of HIV research aiming to cure and eradicate this deadly virus.”
