BOSTON, Sept. 24 (UPI) -- U.S. scientists say the discovery of a new mechanism of immunity suggests a more effective pneumococcal vaccine might be in the offing.
Children's Hospital Boston and Harvard School of Public Health researchers say there might be a better way to protect people against Streptococcus pneumoniae infection. They said the current vaccine, Prevnar, is expensive and covers only 7 of the 91 known pneumococcal strains.
Dr. Richard Malley and medical researcher Marc Lipsitch discovered that, in addition to antibodies, T-cells can provide broad protection against the pathogen. In their new study, Malley and Lipsitch identify the specific protective T-cells and show they protect against infection by releasing a protein that enables human blood cells to kill pneumococcus in the nose more efficiently. That, said the researchers, is significant, since colonizing a person's nose is the first necessary step of infection.
"We are now evaluating vaccine candidates and changing them so they not only induce antibodies, but also induce this specific type of immunity," said Malley. "A vaccine that induces both protective antibodies and T-cell immunity to pneumococcus may be a very effective way to protect against this potentially devastating disease.
The research appears in the journal PLoS Pathogens.
