Escherichia coli O1A O-antigen (O1A O-antigen)

The Escherichia coli O1A O-antigen is a surface-exposed polysaccharide component of the lipopolysaccharide (LPS) found on the outer membrane of specific E. coli strains, particularly those associated with extra-intestinal infections [1, 6]. It serves as a primary target for the host immune system and determines the O-serotype of the bacterium, which is crucial for epidemiological classification and diagnosis [15, 17]. In pathogenic strains, such as extra-intestinal pathogenic E. coli (ExPEC), the O1A antigen plays a vital role in virulence by protecting the bacteria from complement-mediated lysis and opsonophagocytosis [1, 10]. Because of its surface accessibility and high prevalence in clinical infections like urinary tract infections, bloodstream infections, and neonatal meningitis, it is a major target for the development of glycoconjugate vaccines and therapeutic monoclonal antibodies [2, 7, 12]. These interventions, such as the ExPEC9V and ExPEC10V vaccines, aim to induce serotype-specific immunity, facilitating the clearance of the pathogen through opsonophagocytic killing [8, 10].

Other names

E. coli O1A somatic antigenO1A polysaccharideO1A LPSEscherichia coli serotype O1A O-antigen

Induction of opsonophagocytic and bactericidal antibodies against the O1A serotype