Preclinical evaluation of a vaccine based on conserved region of M protein that prevents group A streptococcal infection

Abstract

Background & objectives: Infection with group A Streptococcus (GAS) may result in a number of human diseases ranging from the relatively benign pharyngitis to the potentially life-threatening invasive diseases and post-infectious sequelae. We have previously defined a minimal B-cell epitope from the conserved region of the M-protein. Here we report on the immunogenicity, opsonic potential of the resulting sera and the level of protection induced by this peptide in comparison to a pepsin extract of the M protein. Methods: Inbred mice were immunized with peptides derived from the M protein. Sera were collected from the immunized mice and its opsonic potential determined for M1 and M6 GAS strai..