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From
New Scientist – In a first for any infectious disease, a vaccine against flu has been made out of messenger RNA (mRNA) – the genetic material that controls the production of proteins. Unlike its predecessors, the new vaccine may work for life, and it may be possible to manufacture it quickly enough to stop a pandemic.
We become immune to a flu strain when our immune system learns to recognise key proteins, called HA and NA, on the surface of the flu virus. This can happen either because we have caught and fought off that strain of flu, or because we received one of the standard vaccines, most of which contain killed flu virus.
Flu constantly evolves, however, so those proteins change and your immunity to one year's strain does not extend to following year's. For this reason, a new vaccine has to be produced each year. Most flu vaccines are grown in chicken eggs or cell culture, a process that takes at least six months.
The mRNA that controls the production of HA and NA in a flu virus can be mass-produced in a few weeks, says Lothar Stitz of the Friedrich-Loeffler Institute in Riems Island, Germany. This mRNA can be turned into a freeze-dried powder that does not need refrigeration, unlike most vaccines, which have to be kept cool.
An injection of mRNA is picked up by immune cells, which translate it into protein. These proteins are then recognised by the body as foreign, generating an immune response. The immune system will then recognise the proteins if it encounters the virus subsequently, allowing it to fight off that strain of flu.
Similar vaccines have been made of DNA that codes for flu proteins. But DNA vaccines seem unlikely ever to be approved, because of worries that they might be incorporated into human DNA, disrupting gene regulation.
See more and subscribe to NextBigFuture at 2012-11-26 16:22:48 Source: http://nextbigfuture.com/2012/11/possible-universal-flu-vaccine-made.html