Agglutination by anti-capsular polysaccharide antibody is associated with protection against experimental human pneumococcal carriage.

ABSTRACT: The ability of pneumococcal conjugate vaccine (PCV) to decrease transmission by blocking the acquisition of colonization has been attributed to herd immunity. We describe the role of mucosal immunoglobulin G (IgG) to capsular polysaccharide (CPS) in mediating protection from carriage, translating our findings from a murine model to humans. We used a flow cytometric assay to quantify antibody-mediated agglutination demonstrating that hyperimmune sera generated against an unencapsulated mutant was poorly agglutinating. Passive immunization with this antiserum was ineffective to block acquisition of colonization compared to agglutinating antisera raised against the encapsulated parent strain. In the human challenge model, samples were collected from PCV and control-vaccinated adults. In PCV-v

SUBMITTER: Mitsi E 

PROVIDER: S-EPMC5332540 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature