Each day, advancements are made in the fight against HIV—a virus that plagues a staggering 36.7 million individuals around the world. Recently, the National Institutes of Health (NIH) made another discovery that sheds light on another means by which HIV can spread and infect new cells.
The researchers have found that the virus receives help when it comes to spreading infection, from tiny, “bubble-like structures” called extracellular vesicles (EVs). According to the press release
, most of the time, EVs “are thought to ferry molecules from one cell to another, providing a means of communication.” However, under these circumstances, HIV-infected cells appear to release EVs, which can manipulate “prospective host cells,” thus allowing HIV to spread to other cells.
So, how do EVs created by HIV-infected cells form? The process is similar to how a new virus would form.
A structure forms on the surface of the cell’s outer membrane, “like a bulge on an inner tube,” and then, sooner or later, part of the “membrane bubble” that is closest to the cell surface separates to form a discrete sphere. According to the press release, “In the case of the virus, the sphere contains HIV’s hereditary material, RNA.” However, EVs do not usually contain HIV RNA; in fact, if they do, it’s a very small amount, and so they are not capable of infecting cells.
In the recent study
, published in Scientific Reports
, researchers from Eunice Kennedy Shriver
National Institute of Child Health and Human Development (NICHD) set out to isolate the virus and EVs from infected cultures. After separating the two, they proceeded to test if the virus was capable of infecting new cultures, with and without the help of EVs.