Vibrio cholerae O1 Inaba O-specific polysaccharide antigen (OSP)

The Vibrio cholerae O1 Inaba O-specific polysaccharide (OSP) is a critical surface component of the lipopolysaccharide (LPS) found in the Inaba serotype of Vibrio cholerae O1, the primary causative agent of epidemic cholera [1]. Structurally, it is a homopolymer of alpha(1-2)-linked 4-amino-4,6-dideoxy-D-mannose (D-perosamine) units, which are N-acylated with 3-deoxy-L-glycero-tetronic acid [2]. The Inaba serotype is distinguished from the Ogawa serotype by the absence of a 2-O-methyl group on the non-reducing terminal perosamine residue [2,3]. Biologically, the OSP is essential for maintaining the structural integrity of the bacterial outer membrane and serves as the dominant target for the host's protective immune response [1,4]. Antibodies directed against the OSP, particularly vibriocidal antibodies, are strongly correlated with protection against infection and are the primary mechanism by which oral cholera vaccines (OCVs) confer immunity [3,5]. Consequently, OSP is a central component in the formulation of killed whole-cell vaccines and is a major focus for the development of next-generation conjugate vaccines aimed at providing long-term mucosal protection [4,6]. Sources: [1] Chatterjee & Chaudhuri (2003) Biochim Biophys Acta; [2] Villeneuve et al. (2000) PNAS; [3] WHO (2017) Cholera vaccines: WHO position paper; [4] Grandy et al. (2021) Front Immunol; [5] Harris et al. (2012) Lancet; [6] Xu et al. (2011) Bioconjug Chem.

Other names

Inaba O-antigenVibrio cholerae O1 Inaba O-antigenV. cholerae O1 Inaba O-specific polysaccharideVibrio cholerae O1 Inaba LPS O-antigen

Induction of protective vibriocidal antibodies and mucosal IgA that inhibit bacterial colonization and promote pathogen clearance [3,5].