September 20, 2022  Print

Because viruses are so small, nobody has been able to directly visualise the first moments of HIV transmission. This is a big knowledge gap as, to develop a vaccine and a cure, we need to understand the first cells of the immune system to interact with this virus. 

Researchers led by Professor Andrew Harman from the Westmead Institute for Medical Research have developed technology and an analysis pipeline to not only visualise HIV transmission, but also to accurately quantify it. Furthermore, by developing partnerships with surgeons at Westmead Hospital, our researchers can infect human tissues (in our laboratories) within 15 minutes of their removal from the human body. This is a great example of how collaboration between frontline clinicians and medical researchers can generate unique insights, in this case the creation of a map of early HIV transmission.

Arising from this collaboration, our researchers have revealed three exciting and important new insights into the way HIV is transmitted. The research team proved for the first time that a specific immune cell called a dendritic cell is the first to take up HIV. The research showed that HIV causes other specific immune cells (CD4+ T lymphocytes) to physically interact with dendritic cells so that the virus can infect them. These are the cells that HIV kills leading to the onset of AIDS. Lastly, the research showed that dendritic cells traffic HIV into the deeper tissue layers where it infects macrophages, which are white blood cells that help the immune system by aiding the removal of foreign substances from the body. These cells protect HIV from the drugs used for treatment, which is part of the reason why HIV therapy is lifelong.