It could safely deliver vaccines

May 4, 2009 14:01 GMT  ·  By

The next step in administering antiviral drugs, especially for STDs, could be through the use of biodegradable nanoparticles, able to carry microRNA strands directly to the place of infection and deliver the tiny acid overtime. One day, the innovation, made possible by the efforts of a Yale research team, could result in a brand new form of treatment for such diseases, which currently affect millions around the world. Details of the new technique are published in the May 4th advance online issue of the journal Nature Materials.

Basically, the new type of therapy relies on the great action potential of small interfering RNA (siRNA) molecules, which have the ability to literally silence the genes responsible for the development of this class of diseases. “RNA interference is a promising approach for prevention and treatment of human disease. We wanted to develop a new strategy of delivering siRNAs with a FDA-approved material,” Yale School of Engineering & Applied Science postdoctoral fellow Kim Woodrow, who has also been the lead author of the published study, explained about the research effort.

SiRNAs have the ability to interfere with the action of genes inside organisms as small as microbes, which are one of the main causes for STDs. For this study, conducted entirely on female mice, the experts designed a type of RNA that interfered with the production of a gene widely expressed in the animals' reproductive tract. According to the proof-of-concept results, the particles proved to be highly successful in accomplishing their objectives.

The biodegradable polymer known as PLGA supplied Woodrow with the raw materials she needed to construct densely packed nanoparticles, which carry the siRNAs to their targets. This step of the process was essential, because the Yale team didn't only need a vehicle to get the RNA strands to their designated locations, but also a carrier that would release the acid overtime, so as to maximize its effects. And the researchers succeeded in their quest, as they managed to create a delivery system able to make the RNA linger in the mucosa for up to a week. The effects of the vaccine lasted for up to 14 days.

“Before human clinical testing can begin, our next step in research will be to test this approach directly in disease models – for example in the HIV model mice that have an immune system genetically identical to humans,” the Goizueta Foundation Professor of Biomedical Engineering & Chemical Engineering W. Mark Saltzman, who has also been the senior author of the Nature Materials paper, added.