Salmonella surface antigen

Salmonella surface antigens are a complex array of molecules on the bacterial cell wall that determine the serological identity and virulence of Salmonella species (Source: CDC, 2022). These antigens are traditionally classified into three types: the somatic O-antigen (part of the lipopolysaccharide layer), the flagellar H-antigen (composed of flagellin proteins), and the capsular Vi-antigen found primarily in Salmonella Typhi (Source: StatPearls, 2023). The O-antigen is crucial for structural integrity and protecting the bacterium from the host's complement-mediated killing, while the H-antigen facilitates motility and invasion of host cells (Source: UniProt, 2024). The Vi-antigen acts as a protective shield, preventing antibody binding and phagocytosis, thereby enhancing the systemic spread of the pathogen (Source: PubMed, PMID: 28533306). These surface components are the primary targets for both diagnostic serotyping via the Kauffmann-White scheme and for preventive vaccines (Source: WHO, 2023). Current vaccines, such as the Vi capsular polysaccharide and the live-attenuated Ty21a strain, work by inducing protective immune responses against these specific surface structures to prevent diseases like typhoid fever and salmonellosis.

Other names

Somatic O antigenFlagellar H antigenCapsular Vi antigenSalmonella lipopolysaccharideKauffmann-White antigensBacterial surface antigens (Salmonella)

Active immunization through the induction of humoral and cellular immune responses against bacterial surface components to prevent host cell attachment and invasion; or direct binding and neutralization of lipopolysaccharide components to mitigate endotoxicity.