The study of the mechanism of formation of HIV capsid can be the basis for developing a new type of therapy
Scientists from the University of New South Wales (UNSW, UK) found that the special protein capsid envelope created by HIV at the time of entry into the human body uses a specific host cell molecule, inositol-hexakisphosphate, as a shield from immunity. The latter gives the capsid stability and allows unhindered to carry the genetic material of the virus to the nucleus of the cell. According to experts, this discovery can be the first step to changing the strategy of HIV treatment. A new goal for antiviral therapy, scientists suggest to make the capsid itself.
A group of British specialists, using a new method of unimolecular microscopy, developed at the Faculty of Molecular Science of UNSW at the Medical Faculty, found that HIV, creating a shield against immunity, to strengthen its capsid includes a specific molecule of the host cell, inositol-hexakisphosphate. Thus, the body unintentionally provides HIV with a key for infection, blocking the protective shell and keeping a safe genetic load until it is immersed in the nucleus.
"The HIV capsid breaks down after a few minutes if it is isolated from the virus," said study leader Till Böcking.
"Our strategy allows us to accurately describe how the capsid can be destroyed in real time without leaving the viral membrane."
As noted by the portal EurekAlert!, with the support of Stuart Turville from the Kirby Institute team developed special viruses with fluorescent labels to monitor the life of the capsid.
"Now we can see the influence of different molecules on the capsid and accurately determine when it starts to break down," Bucking said.
"Capsids should be much more stable inside the cell, because the process of infection takes several hours, not minutes. Given this, we wanted to find out what keeps it in the cage, "said co-author of the study, Dr. David Jacques.
The scientists found that inositol-hexakisphosphate, which is present in large numbers inside mammalian cells, makes the capsid much stronger, stabilizing it for 10-20 hours.
"It's like a switch. When you bind this molecule, you stabilize the capsid and open the path to the cell to penetrate it", explains Becking.
"The HIV Capsid has been studied extensively for a long time, but the question of its stability and balance at the time of the" merger "has so far been one of the key in HIV biology," commented Dr. Leo James, head of the research group at the Laboratory molecular biology Research Council in Cambridge.
We add that most of the currently approved HIV treatment methods are aimed at the enzymes required by the virus at different stages of the life cycle, but none of them has yet been directed to the HIV capsid.
According to experts, drugs of a different principle of action will increase the effectiveness of HIV treatment and reduce the toxic effect of therapy on the body.