German researchers have found a natural component of human blood that block the HIV virus from infecting cells, and would be more potent to fight the HIV virus.
There is also evidence that HIV doesn’t easily develop resistance to the new compound, which is a major problem with many current HIV treatments, researchers said.
The molecule, known as VIRIP (virus-inhibitory peptide), binds to a spiky protein on the surface of the HIV virus called gp41. HIV normally uses this protein to make the first contact with and latch onto a human cell, after which it would infect it. But the intervention of VIRIP stops that contact from happening, it explained.
The molecule was found by Frank Kirchhoff of the University of Ulm in Germany and his colleagues, who report their work in the journal Cell.
The synthetic version has been shown to be safe in animals and the team hopes to begin trials in humans this year, researchers said.
They screened a massive library of compounds isolated from 10,000 litres of filtered human blood, looking for substances that could naturally inhibit HIV. Human blood has yielded some HIV-inhibiting substances before, the report said.
Pinpointing exactly which compounds have an effect is difficult, lots of blood is needed to be able to single out and test enough of each compound found. Kirchhoff’s team had access to a large library of blood compounds at IPF PharmaCeuticals, a pharmaceutical company in Germany keen to develop the work.
Once they had isolated the protein, Nature magazine said, the team set about adjusting it to explore which changes to its structure might alter its function, by fiddling with the amino acids in its 20-amino-acid chain.
In one instance, the researchers found that adding just one specific amino-acid building block rendered the protein useless in protecting against HIV. “We were surprised it was so specific,” says Kirchhoff adding “it is really striking.”
Of the mass number of alterations the team tested, they found one instance in which altering just three specific amino acids made the compound 100 times more effective at inhibiting HIV a potent drug candidate.
The group, the report says, has already tested this modified version in animal models, including rats, dogs and monkeys, to make sure it is not toxic. The unpublished results look promising, Kirchhoff says, and the molecule could be ready for clinical trials by the end of this year.
Another bonus is that HIV should not be able to develop resistance to VIRIP as easily as it can with other drug compounds.