AUTHOR=Dolbec Dominic , Lehoux Mélanie , Okura Masatoshi , Takamatsu Daisuke , Gottschalk Marcelo , Segura Mariela 

TITLE=Streptococcus suis surface-antigen recognition by antibodies and bacterial elimination is influenced by capsular polysaccharide structure

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=13

YEAR=2023

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2023.1228496

DOI=10.3389/fcimb.2023.1228496

ISSN=2235-2988

ABSTRACT=<p><italic>Streptococcus suis</italic> is an encapsulated bacterium causing severe diseases in swine. Here, we compared the protective properties of the capsular polysaccharide (CPS) of different <italic>S. suis</italic> serotypes by using serotype-switched mutants in a mouse model of infection. CPS structure influenced bacterial survival in mice, antibody binding, and antibody-mediated bacterial killing. The CPS of serotypes 3, 4 and 14 allowed more antibody binding and bacterial elimination than the CPS of serotypes 2, 7 and 9. Results suggest that the different CPS structures of <italic>S. suis</italic> provide varying levels of protection by influencing antigen availability and elimination by the host immune system.</p>