Streptococcus suis antigen (S. suis antigen)

Streptococcus suis antigens are a heterogeneous group of molecules found on the surface or secreted by the bacterium Streptococcus suis, a major porcine pathogen and emerging zoonotic agent (Goyette-Desjardins et al., 2014). These antigens include the capsular polysaccharide (CPS), which is the primary basis for serotyping, and various virulence-associated proteins such as Suilysin (Sly), Muramidase-released protein (MRP), and Extracellular factor (EF) (Segura et al., 2017). Biologically, these components facilitate host cell adhesion, invasion, and evasion of the host immune system, particularly through the inhibition of phagocytosis by the capsule (Vötsch et al., 2018). In the context of disease, these antigens are central to the development of porcine and human meningitis, septicemia, and endocarditis (Dong et al., 2021). From a therapeutic perspective, they serve as the primary targets for the development of subunit, conjugate, and DNA vaccines aimed at inducing protective humoral and cellular immunity (Segura, 2020). However, the significant antigenic diversity across more than 30 serotypes complicates the development of a broadly protective vaccine, often requiring the use of autogenous vaccines tailored to specific farm outbreaks (Segura, 2020). This target entry is flagged as incorrect/broad because it refers to a collective category of diverse molecular entities rather than a single defined protein or receptor.

Other names

Streptococcus suis surface proteinsS. suis virulence factorsPorcine streptococcal antigensStreptococcus suis capsular polysaccharide

Induction of active immunity through the presentation of bacterial epitopes to B and T cells, leading to the production of neutralizing antibodies and immunological memory to prevent bacterial colonization and systemic spread (Segura, 2020).