French researchers have managed to capture the exact time of an HIV infection on video. It shows how an infected cell transmits the AIDS virus to another cell. So this is the first film to show this fatal phenomenon at work. The scene takes place in a test tube in a laboratory at the Cochin Institute in Paris.
One with the humaneImmunodeficiency virusThe researchers brought an infected cell (HIV) into contact with a healthy cell. When the first suddenly “pulls” on the last, this is the first time that scientists have filmed the live transmission of the AIDS virus from one cell to another. Although the main lines of mechanisms of HIV infection discovered in 1983 are known, this work, published in the journal Cell, sheds new light on them.
The team primarily used Morgane Bomsel as a cell type involved in the transmission of AIDS, which is particularly common in vaginal secretions, semen or breast milk. The researchers marked the HIV-infected cell seen in the videos in fluorescent green for easy identification. The scientists then released these onto a male urethral mucosa that had been reconstructed in the laboratory. So this is a tissue that represents the first line of sexual HIV infection. Specifically, it is the epithelial cells (shown in blue in the videos) that the team targeted. These cells cover the external or internal surfaces of many organs.
Like a shot
When it approaches another cell that is already infected with HIV, it forms a virological synapse. This is a kind of bridge that connects the two and the formation of which stimulates the production of virus particles. Accordingly, they are ready to attack the healthy cell. The particles are then expelled towards the epithelial cells. This happens “like the fluorescent green beam from a blaster pistol in an old science fiction movie,” describes Morgane Bomsel.
However, instead of attaching to the epithelial cells, the AIDS virus simply crosses them. The cell waits for the immune system's guardians, the macrophages, to be alerted. Once they are on site to phagocytose the foreign body recognized by the body, it includes the HIV infection, whose specificity is precisely to attack the immune cells. It is precisely this final stage that represents a true discovery of these processes.
You can find out more about this on the websiteUNAIDS.
