Salmonella in vaccines for babies?
The challenge in making a vaccine is to deliver a highly infectious disease to the liver and spleen hence enabling the body to trigger a strong immune response and then to disable it once the immune system has completed its job. Previously in making vaccines safe scientists faced the problem that in doing so, it may only cause a localized effect. Roy Curtiss from Arizona State University’s Biodesign Institute says, “If you make something safe and sort of cut off both arms and both legs, it can’t get to where it needs to go in the body’.
Salmonella is a violent and very dangerous disease and can ravage the body’s defenses. Researchers have now found a novel way of using Salmonella’s speed and ferocity to trigger a powerful immune response. Curtiss and his colleagues have genetically altered the Salmonella to contain a delayed self destruct mechanism. They produced a salmonella strain that requires sugars that are not available in the human body (only in the lab) once the salmonella runs out of this sugar, its cell walls burst. Curtiss says. “We’ve got the Salmonella on a string. We can decide when to snap the string, and they’re gone.”
They are hoping to make a vaccine for infant bacterial pneumonia, the cause of 2 million deaths every year worldwide.
http://www.sciencedaily.com/releases/2009/01/090112201240.htm
