Scientists find ‘key’ that allows HIV to unlock body’s cells

Scientists have found the “key” that HIV uses to enter the centre of human body cells, allowing it to disable the immune system and cause Aids.

The discovery provides a potential new target for treatments that could be more effective against drug-resistant strains of the virus.

HIV is transmitted through infected body fluids and once inside the bloodstream the virus infects key components of the immune system.

When the virus first came to prominence in the 1980s, the high numbers of intravenous drug users affected in Edinburgh lead to the label “HIV capital of Europe” being slapped on the city.

The virus works its way into the nucleus of cells known as macrophages, where it merges itself into the cell’s DNA, allowing it to replicate and spread throughout the body.

To access the DNA, the virus must pass through a gateway into the nucleus called the nuclear pore complex. Until now, the mechanism that allows the virus to pass through this gateway was unknown. A team of scientists from University College London (UCL), the University of Pennsylvania School of Medicine and the Laboratory of Molecular Biology in Cambridge, have identified a vital component of this mechanism.

A part of the HIV virus called the capsid protein, acting like a key, attaches itself to a protein on the nuclear pore complex, called Nup358, effectively unlocking the gateway and granting the virus access to the DNA.

Professor Greg Towers, a Wellcome Trust Senior Research Fellow at UCL, who led the research, said that the discovery would allow them “to stay one step ahead” of the virus.

“It’s 30 years since the first cases of Aids were reported and whilst great progress has been made in developing and improving anti-retroviral drugs for treating HIV infection, the virus often develops resistance against these drugs making it very difficult to treat. It’s very important that we stay one step ahead with new therapeutic strategies.

“In our research, we have found the ‘lock and key’ that allow HIV to enter a cell’s nucleus. Once inside, the virus can begin to replicate itself, spreading almost unchecked throughout the body. If we were able to block this entry with a drug – in effect, to change the locks – then we could stop this spread.”

Targeting proteins in the host, rather than in the virus itself, has added benefits in treatment, explained one of the researchers who has written up the findings, Dr Torsten Schaller. He said: “We know that HIV can easily evolve and change, which means that the virus can become immune to the effects of the drugs, rendering them ineffective.”

Blake Smith, of Terrence Higgins Trust, said: “This could lead to the development of an innovative drug.”