Streptococcus suis antigens (S. suis antigens)

Streptococcus suis antigens comprise a diverse array of molecules, including the capsular polysaccharide (CPS), surface-associated proteins, and secreted toxins, which are central to the pathogenicity of this major swine pathogen and emerging zoonotic agent (Segura et al., 2020, Pathogens). The CPS is the most critical antigen for serotyping and immune evasion, acting as a shield that protects the bacteria from phagocytosis by host immune cells (Goyette-Desjardins et al., 2014, Emerging Microbes & Infections). Other significant antigens include suilysin (SLY), a cholesterol-dependent cytolysin that causes tissue damage, and proteins like muramidase-released protein (MRP) and extracellular factor (EF), which are markers for highly virulent strains (Staats et al., 1997, Veterinary Research Communications). These antigens serve as the primary targets for the development of vaccines, including autogenous bacterins and recombinant subunit vaccines, aimed at controlling porcine streptococcosis and preventing transmission to humans (Haas & Grenier, 2018, Future Microbiology). In humans, these antigens are involved in the development of severe systemic infections such as meningitis and septicemia, particularly in individuals with occupational exposure to pigs (Wertheim et al., 2009, PLoS Medicine). Current therapeutic research focuses on identifying conserved surface proteins to develop universal vaccines that can overcome the limitations of serotype-specific approaches.

Other names

Streptococcus suis surface proteinsS. suis virulence factorsStreptococcus suis capsular polysaccharidesS. suis immunogensPorcine streptococcal antigens

Vaccines targeting these antigens work by inducing the production of specific IgG antibodies that neutralize toxins like suilysin or act as opsonins to facilitate the phagocytosis and killing of the bacteria by host neutrophils and macrophages (Segura, 2015, Expert Review of Vaccines). Antibiotics interact indirectly by targeting the bacterial cell wall or protein synthesis, leading to the degradation and clearance of these antigenic components.