Please avoid such messages. ----- Original Message ----- From: "Renuka Warriar" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Friday, April 20, 2007 9:40 PM Subject: [AI] Blood may hold clue to new HIV drug: researchers
> The Hindu News Update Service > > News Update Service > Friday, April 20, 2007 : 1445 Hrs > > Sci. & Tech. > Blood may hold clue to new HIV drug: researchers > > New York, April 20. (PTI): A natural component of human blood has been > found to block the HIV virus from infecting cells, raising hopes that a > novel class > of drugs could be developed to fight the 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. > > 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. > > Half of the patients given a drug called T20, for example, which also acts > to prevent HIV entering the cell, develop resistance to it, Neelanjana > Ray, a > virologist at the University of Pennsylvania in Philadelphia, is quoted as > saying. > > This is because HIV has proven to be very adaptable; many of its surface > proteins constantly change. But VIRIP picks on a fairly stable surface > protein, > which does not change so much - it works in conjunction with another > protein, called gp120, which was recently discovered to be conserved over > time. > > This means that drug using it should remain effective. "The really good > thing is that it targets a very conserved area," says Ray adding "It does > seem to > be a promising candidate." > > To unsubscribe send a message to [EMAIL PROTECTED] > with the subject unsubscribe. > > To change your subscription to digest mode or make any other changes, > please visit the list home page at > http://accessindia.org.in/mailman/listinfo/accessindia_accessindia.org.in To unsubscribe send a message to [EMAIL PROTECTED] with the subject unsubscribe. To change your subscription to digest mode or make any other changes, please visit the list home page at http://accessindia.org.in/mailman/listinfo/accessindia_accessindia.org.in
