Mediaboss Marketing

Featured Article Academic Journal Main Category: Infectious Diseases / Bacteria / Viruses Also Included In: Biology / Biochemistry Article Date: 15 Sep 2012 - 3:00 PDT

Current ratings for: Killer Virus Uses Protein Wrap To Evade Immune System

Writing about their work in the 13 September issue of the online open access journal PLoS Pathogens, lead researcher Erica Ollmann Saphire, and colleagues, suggest their breakthrough offers new targets for drugs and vaccines.

The virus was discovered in the 1960s after lab scientists in Marburg in Germany and other labs in Europe, became infected. The lab in Marburg was using African green monkeys and their tissue to develop a polio vaccine. The five species of Ebola virus are the only other known members of the filovirus family.

The virus has been imported into the United States (Colorado) and the Netherlands by tourists who visited Africa.

There is currently no cure for Marburg infection, which is spread when people come into contact with bodily fluids from an infected person or animal. Most people die within two weeks, from dehydration, massive bleeding and shock: a small proportion have naturally strong and immediate immune responses and survive.

"When these are sensed, an immediate antiviral defense is launched. However, the Marburg and Ebola viruses mask the evidence of their own infection. By doing so, the viruses are able to replicate rapidly and overwhelm the patient's ability to launch an effective defense," she explains.

The immune system relies on being able to recognize the double stranded RNA (dsRNA) at the heart of viruses: this "key signature" of virus infection is detected by "host sentry proteins" like RIG-I and MDA-5, write the authors.

And they had also, from examining the crystal structure of the protein from two ebolaviruses, showed that it formed "an asymmetric dimer to cap the ends of dsRNA molecules".

But what was not clear, until this study, was whether the protein was able to mask the lengths of dsRNA that lie between the ends of the molecules.

More:
Killer Virus Uses Protein Wrap To Evade Immune System