Utilization of cholera toxin B as a mucosal adjuvant elicits antibody-mediated protection against S. pneumoniae infection in mice

The introduction of the pneumococcal conjugate and polysaccharide vaccines have been valuable tools for combating invasive pneumococcal infection in children and healthy adults. Despite the available vaccination strategies, pneumococcal pneumonia and associated diseases continue to cause substantial morbidity and mortality, particularly in individuals with chronic disease and ageing populations. Next-generation pneumococcal vaccines will need to be highly immunogenic across patient populations providing both mucosal and systemic protective immunity. Mucosal immunization is an effective strategy for stimulating the immune response at the site of pathogen entry while increasing systemic immunity. In this study we utilized intranasal immunization with pneumococcal surface protein A (PspA), in combination with the mucosal adjuvant cholera toxin B (CTB), to characterize the immune components providing protection against S. pneumoniae challenge