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Commensal Streptococcus mitis is a unique vector for oral mucosal vaccination
Nada Daifalla1, Mark J Cayabyab1, Emily Xie1
1The Forsyth Institute, Cambridge, MA, United states.
Microbes and Infection
|December 20, 2014
Summary
This study shows Streptococcus mitis can be a vaccine vector. Oral delivery of engineered S. mitis induced immune responses against tuberculosis antigens in piglets.
Area of Science:
- Microbiology
- Immunology
- Vaccinology
Background:
- Developing effective vaccines requires inducing both mucosal and systemic immune responses.
- Mucosal immunization is crucial for preventing infections transmitted through mucosal surfaces.
Purpose of the Study:
- To evaluate Streptococcus mitis as a potential delivery vehicle for mucosal vaccination.
- To assess the immunogenicity of an engineered S. mitis strain expressing a Mycobacterium tuberculosis antigen.
Main Methods:
- Engineered a stable strain of Streptococcus mitis (rS. mitis) using homologous recombination to express the Mycobacterium tuberculosis Ag85b protein.
- Administered the rS. mitis orally to gnotobiotic piglets.
Main Results:
- Achieved efficient oral colonization with the engineered S. mitis in gnotobiotic piglets.
- Observed the production of specific IgA and IgG antibodies against Ag85b in both oral and systemic sites.
- Demonstrated that oral administration of rS. mitis led to a robust immune response.
Conclusions:
- Commensal Streptococcus mitis can serve as a viable vector for mucosal vaccination.
- This approach shows promise for developing new strategies against infections like tuberculosis.
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