Process of HIV infection recorded on video

Molecular biologists from France have managed to create the first video recording of the infection of a human cell by the Human Immunodeficiency Virus (HIV). 

“HIV transmission has not been studied much and we had no precise idea of the exact sequence of events leading to HIV infection of genital fluids during sexual intercourse. Neither did we know how immune cells are infected and what the consequences are.” Dr Morgane Bomsel, Research Team Director at the French National Center for Scientific Research (CNRS).

To make this video, the researchers created a model of genital tissue consisting of epithelial cells. The virus affecting immune system cells is marked with a green fluorescent protein.

When HIV-infected T-cell come into contact with each other, a special structure (viral synapse) is formed that allows viral particles to move from an infected cell to a healthy one. After that, these particles are emitted in the form of rays (green rays in the video) that penetrate the epithelial cells.

The virus does not infect epithelial cells, but moves through them, and then is absorbed by macrophages - another type of immune cells targeted by HIV.

After about 20 days, the virus enters an "inactive" phase, but remains inside the macrophages. That's one reason why it's difficult to detect it in the first stages.

Researchers believe that one of the tasks of combating HIV is to avoid the formation of a viral reservoir in macrophages. To do this, you need to start affecting the virus as early as possible. The discovery made by experts from France "sheds light on the first steps of HIV transmission," which can help solve this problem.