Vaccine-induced protection against gastrointestinal bacterial infections in the absence of secretory antibodies

Abstract

Secretory IgA (SIgA) is widely held to be responsible for the defense of the mucosae against pathogenics and other potentially harmful agents. In this study, polymeric Ig receptor (pIgR) knockout mice, which lack secretory antibodies (SAb), were used to investigate the role of vaccine-elicited SAb in protection against gastrointestinal bacterial infections. An essential role for specific SAb in protection against Vibrio cholerae was evident from experiments showing that vaccinated pIgR(-/-) mice, but not vaccinated C57BL/6 mice, were susceptible to cholera toxin challenge. Vaccination of C57BL/6 mice with Salmonella typhimurium elicited strong antigen-specific, mucosal responses, which block..