Poster Presentation 20th Lancefield International Symposium on Streptococci and Streptococcal Diseases 2017

TeeVax – a multivalent T-antigen-based vaccine against group A streptococcus (#165)

Jacelyn Loh 1 , Natalie Lorenz 1 , Adrina Khemlani 1 , Thomas Proft 1
  1. University of Auckland, Victoria Street West, AUCKLAND, New Zealand

The surface of group A streptococcus is decorated with hair-like appendages known as pili. These are involved in adhesion and colonisation of the host during infection. The major protein component of the pilus is the T-antigen which multimerises to form the pilus shaft. Recent genomic analysis of tee genes from strains circulating in New Zealand revealed that inclusion of 18 different T-antigens in a vaccine should provide over 90% coverage (Steemson et. al. Journal of Medical Microbiology (2014), 63, 1670–1678). The T-antigen therefore represents an attractive target for vaccination. Our aim is to fuse protein domains from up to 6 different T-antigens, and combine up to 3 fusion proteins in the final multivalent vaccine. The first 2 of these fusion proteins have been successfully expressed and purified. Antibody responses were measured by ELISA and an in vitro bioluminescent bactericidal assay developed in our lab. Our results show that rabbits immunised with these TeeVax proteins elicit strong antibody responses that are able to mediate opsonophagocytotic killing of group A streptococcus.