Nanosponge vaccine fights MRSA toxin

Liangfang Zhang, a nanoengineering professor from the University of California San Diego, published a new study on Sunday in Nature Nanotechnology that showed a toxin produced by methicillin-resistant Staphylococcus aureus can be absorbed by nanosponges.

Zhang said that when the toxin is absorbed by the "nanosponge vaccine," the immune system was able to block the adverse effects of the toxin within the bloodstream and on the skin.

"With our toxoid vaccine, we don't have to worry about antibiotic resistance," Zhang said. "We directly target the alpha-haemolysin toxin. These toxins create a toxic environment that serves as a defense mechanism, which makes it harder for the immune system to fight Staph bacteria."

The nanosponges are enclosed in a red-blood-cell membrane, which "seizes and detains" the Staphylococcus aureus toxin. In this way, the nanosponges serve as a vaccine that triggers antibodies to fight off the toxin.

Zhang said this method of vaccine could be used to treat other bacteria-produced toxins, such as those from E. coli and H. pylori.

Research showed the nanosponge vaccine was more effective than toxoid vaccines, which are produced from heat-treated toxin. In the study, survival rates increased to 50 percent with the nanosponge vaccine, instead of 10 percent with the heat-treated toxin.

"The more you heat it, the safer the toxin is, but the more you heat it, the more you damage the structure of the protein," Zhang said. "And this structure is what the immune cell recognizes, and builds its antibodies against."