A vaccine to provide strain-transcending immunity to group A streptococci

Abstract

Organisms such a Streptococcus pyogenes (group A streptococcus), Plasmodium spp parasites and HIV present significant obstacles to vaccine development. They can subvert the immune system and present dominant antigens that can display a vast array of allelic types of variants. In spite of these obvious decoys, the main strategy to develop vaccines for these organisms has been to focus on dominant antigens or epitopes. The obvious reason for this approach is that such antigens and epitopes are easy to define. Early successes are often posted largely because homologous organisms are typically used to challenge animals post-vaccination. However, success in efficacy trials with heterologous challenge is yet to be seen.