Mohammed Alsharifi
The University of Adelaide, Australia
Title: Human Rotavirus vaccine: A decade of experience vaccinating infants worldwide
Biography
Biography: Mohammed Alsharifi
Abstract
Streptococcus pneumoniae and influenza are the world’s foremost bacterial and viral respiratory pathogens. We have previously described a gamma-irradiated influenza (γ-FLU) vaccine that provides cross-protective immunity against heterosubtypic infections. More recently, we reported a novel non-adjuvanted gamma-irradiated S. pneumoniae (γ-PN) vaccine that elicits serotype-independent protection. Considering the clinical synergism of both pathogens, combination of a serotype-independent pneumococcal vaccine with a broad-spectrum influenza vaccine to protect against both infections would have considerable clinical impact. In this study we co-immunised C57BL/6 mice intranasally with a mixture of γ-PN (whole inactivated cells) and γ-FLU (whole inactivated virions) and examined protective efficacy. Co-immunisation enhanced γ-PN vaccine efficacy against virulent pneumococcal challenge, which was dependent on CD4+ T cell responses. Furthermore, co-immunisation elicited significant protection against lethal influenza challenge, as well as against co-infection with both influenza and S. pneumoniae. This is the first report showing the synergistic effect of combining whole cell and whole virion vaccines to both S. pneumoniae and influenza as a single vaccine to protect against individual and co-infection, without compromising pathogen-specific immunity.