Lipopolysaccharide O:2 antigen (LPS O:2)

Lipopolysaccharide O:2 antigen is a specific polysaccharide component found on the outer membrane of certain Gram-negative bacteria, most notably Salmonella enterica serovar Paratyphi A (PubMed: 25644322). As part of the lipopolysaccharide (LPS) complex, the O:2 antigen serves as the outermost domain, playing a critical role in protecting the bacterium from host immune defenses and environmental stress (NCBI: NBK7907). It is a primary target for the host's humoral immune response, making it a significant focus for vaccine development and diagnostic serotyping (PubMed: 30216179). In clinical settings, the O:2 antigen is used to identify specific bacterial strains associated with enteric fever, urinary tract infections, and other systemic infections (PubMed: 11516411). Therapeutic strategies targeting this molecule often involve the use of glycoconjugate vaccines or monoclonal antibodies designed to promote opsonophagocytosis and pathogen clearance (PubMed: 28838618). Understanding the structure and variability of the O:2 antigen is essential for managing outbreaks and developing effective antimicrobial interventions.

Other names

O2 antigenO-antigen 2Salmonella Paratyphi A O-antigenGroup A O-antigenE. coli O2 antigen

Induction of serotype-specific bactericidal antibodies and opsonophagocytosis to neutralize the pathogen (PubMed: 28838618).