Immunogenicity of a Live RecombinantSalmonellaentericaSerovar Typhimurium Vaccine ExpressingpspAin Neonates and Infant Mice Born from Naïve and Immunized Mothers

• DOI: 10.1128/cvi.00413-09
• Publication Date: 2010-01-07T03:05:03Z
• Authors: Huoying Shi; Shifeng Wang; Kenneth L. Roland; Bronwyn M. Gunn; Roy Curtiss
• Keywords: Salmonella enterica

We are developing a Salmonella vectored vaccine to prevent infant pneumonia and other diseases caused by Streptococcus pneumoniae. One prerequisite for achieving this goal is construct evaluate new recombinant attenuated (RASV) strains suitable use in neonates infants. enterica serovar Typhimurium strain chi9558(pYA4088) specifies delivery of the pneumococcal protective antigen PspA can protect adult mice from challenge with S. This completely safe oral day-old mice. Here we assess colonizing ability, immunogenicity, efficacy neonatal Colonization was assessed 0, 2, 4, or 7 days age after inoculation. In presence maternal antibodies, colonization lymphoid tissues delayed, but immune responses were enhanced born immunized mothers. Both intranasal routes used immunogenicity. All orally intranasally either naïve mothers developed PspA-specific mucosal systemic responses. Mice produced higher titers antibodies blood mucosa greater numbers interleukin-4 (IL-4)-secreting cells than More importantly, showed significant increase protection against pneumoniae challenge. These results suggest that circumvent some limitations immature system mice, generating antibodies.