January 25, 2011

January 25, 2011
New HIV Therapy?


Welcome to another day in my life. Today is Tuesday and I hope you are having a safe and great week so far. Dab the AIDS Bear and I are off and running this week trying to keep up with all of our meetings, conference calls and public appearances.

I read a very interesting article about possible new HIV therapy so I thought I would blog about the issue today.

Australian researchers from Johnson & Johnson Research Pty. Ltd. have been studying new ways to fight HIV by exploiting the recently discovered gene silencing mechanism called RNA interference (RNAi), according to a news release issued on January 11 by BioMed Central. The hope of finding new, effective drugs to treat HIV infection by launching a manifold attack on the viral genome has significantly increased, thanks to new research published in the journal AIDS Research & Therapy. HIV is a difficult virus to treat because it mutates very rapidly.

According to the release, they have created hundreds of small molecules called short hairpin RNA (shRNA), designed against the thousands of HIV variants known to currently exist. shRNA harnesses RNAi such that individual genes can be highly specifically turned off at will. It has been known for some time that single shRNAs can attach to the genetic material of HIV and stop the production of certain gene products. Unfortunately, like traditional drugs, the effect of a single shRNA is short lived as HIV rapidly mutates to escape RNA interference. Using a cocktail of four different shRNAs at the same time, however, significantly reduces the virusí ability to mutate and escape the genetic attack. By studying thousands of different combinations of shRNAs, the team has identified several combinations to cover all variants commonly found in the USA and Europe.

Principal investigator Glen McIntyre said the difficulty in finding a single combination of shRNAs to fight HIV is that there are many different variants that have to be accounted for. The trick is to search for combinations of slightly more shRNAs (than minimally needed for a single variant) so that there will be at least one suitable sub-combination for each different variant likely encountered. Not only did we want our combinations (of shRNA) to cover all currently known subtype variants, but we also aimed for them to actively prevent the emergence of any new, resistant variants.

The teamís persistence has paid off and they have created a number of combinations of six to seven shRNAs designed to suppress every single variant of HIV belonging to the clade B subtype, the most common group found in the U.S. and Europe. The goal now is to test the best combinations in long term experiments against different variants to see if they hold up as expected, and particularly in preventing new variants from emerging.

So it will be interesting to see what develops from these findings. But it gives me hope as we seem to be getting closer and closer to the answers as we start the fourth decade of dealing with this virus.

Until we meet again; here's wishing you health, hope, happiness and just enough.



big bear hug,





Daddy Dab