Vibrio cholerae O1 O-specific polysaccharide (OSP)

Vibrio cholerae O1 O-specific polysaccharide (OSP) is the primary surface antigen of the Vibrio cholerae bacterium, which causes the acute diarrheal disease cholera (Harris et al., 2012, https://pubmed.ncbi.nlm.nih.gov/22230232/). It is a component of the lipopolysaccharide (LPS) and determines the serogroup (O1) and serotypes such as Inaba and Ogawa (Chatterjee & Chaudhuri, 2003, https://pubmed.ncbi.nlm.nih.gov/12692281/). The OSP is composed of a homopolymer of alpha(1-2)-linked 4-amino-4,6-dideoxy-D-mannose (perosamine) residues (Villeneuve et al., 2000, https://pubmed.ncbi.nlm.nih.gov/10854134/). It is a critical target for the host immune system; antibodies against OSP, known as vibriocidal antibodies, are strongly correlated with protection against infection (Leung et al., 2004, https://pubmed.ncbi.nlm.nih.gov/15175298/). Therapeutically, OSP is the key component in oral cholera vaccines (OCVs) and is being developed as a conjugate vaccine (OSP-protein conjugates) to improve immunogenicity, especially in young children (Sarkar et al., 2019, https://pubmed.ncbi.nlm.nih.gov/31151943/). Targeting OSP via vaccination prevents the bacteria from colonizing the small intestine and neutralizes its pathogenic potential (World Health Organization, 2024, https://www.who.int/news-room/fact-sheets/detail/cholera).

Other names

O-antigenO-polysaccharideVibrio cholerae O1 O-antigenV. cholerae O1 OSPLipopolysaccharide O-antigen

Induction of protective vibriocidal antibodies and mucosal IgA to prevent bacterial colonization and promote pathogen neutralization.