A new type of vaccine could stimulate the innate immune system to prevent deaths from hospital-acquired infections caused by a variety of bacteria and fungi, according to a recent study.
The study, published Oct. 4 in Science Translational Medicine, tested protein-free vaccines on mice. Traditional vaccines teach the body's adaptive immune system to recognize and remember a protein from a single type of microbe, but the alternative approach stimulates the innate immune system.
The study found that the innate immune cells "keep a kind of memory, lasting weeks to months, that allows them to react more effectively the second time they encounter a pathogen." In mice, the vaccine protected against death from a bloodstream infection of methicillin-resistant Staphylococcus aureus, but did not protect against death from pneumonia. In an additional test, the vaccine protected mice from several different microbes delivered to the bloodstream or the lungs.
The vaccine provided protection within 24 hours and up to 28 days. After a booster shot, protection continued for several weeks.