Shigella surface antigens

Shigella surface antigens are a complex array of molecules located on the outer membrane of Shigella species, primarily comprising the O-antigen component of lipopolysaccharide (LPS) and the invasion plasmid antigens (Ipa) associated with the Type III secretion system (T3SS) [Mani et al., 2016]. These antigens are essential for the pathogenesis of shigellosis, facilitating bacterial adhesion, invasion of the colonic epithelium, and subsequent escape from the phagocytic vacuole [Schroeder and Hilbi, 2008]. The O-antigen is the primary target for protective humoral immunity and defines the various serotypes of Shigella, such as S. flexneri and S. sonnei [Phalipon and Sansonetti, 2007]. Therapeutic interventions targeting these antigens include glycoconjugate vaccines, which link the O-antigen to carrier proteins to enhance immunogenicity, and live-attenuated vaccines that express these surface components [Cohen et al., 2022]. Additionally, monoclonal antibodies are being explored to neutralize the T3SS machinery or the LPS layer directly. A significant challenge in targeting these antigens is the high degree of serotype specificity, necessitating the development of multivalent formulations to ensure broad protection against the diverse strains causing global diarrheal disease [Mani et al., 2016].

Other names

Shigella O-antigenShigella lipopolysaccharideInvasion plasmid antigensIpa proteinsShigella Type III secretion system proteins

Induction of protective humoral immunity (IgG/IgA) against O-antigen to prevent bacterial colonization and invasion; neutralization of the Type III secretion system to block entry into host epithelial cells.