Using a new approach to vaccine development, researchers may have come up with a potential solution to the problem of antibiotic-resistant bacteria.
Their experimental vaccine provided mice with high levels of immunity from lethal levels of Staphylococcus aureus and its “superbug” form methicillin-resistant S. aureus, or MRSA, researchers reported on Wednesday (24/4) in Nature Communications.
Overuse of antibiotics has helped lead to the evolution of superbugs resistant to most commonly available treatments. New antibiotics or other solutions are badly needed, health experts say.
To develop a vaccine, researchers must identify a molecule that the body will flag as foreign. These molecules, or antigens, trigger the immune system to create antibodies to fight future infections.
While most vaccines rely on protein antigens, the new vaccine uses a carbohydrate called polysaccharide poly-beta-(1−6)-N-acetylglucosamine, or PNAG, which is present on the cell wall of many bacteria.
The scientists were able to identify 32 PNAG carbohydrates, all comprised of five sugars but with differing patterns of certain molecular components that are either bound to another small molecule called an acetyl group or that are not bound to anything else.
The team found two PNAG versions that were especially promising and attached them to a virus that infects bacteria.
Coupled with the virus, the two PNAG combos provided mice with “near complete protection” against infections by S. aureus and MRSA, with minimal impact on the healthy organisms that live in the intestines, the researchers said.
The widespread presence of PNAG in multiple bacteria “render it an attractive target for vaccine development,” they added.