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Epithelial Cell Infection Analyses with Shigella
Published on: February 9, 2024
Mucosal immunization with Shigella flexneri outer membrane vesicles induced protection in mice
A I Camacho1, J de Souza, S Sánchez-Gómez
1Department of Microbiology, University of Navarra, 31008 Pamplona, Spain.
Vaccine
|September 14, 2011
Summary
A novel nanoparticle-adjuvanted Shigella flexneri outer membrane vesicle (OMV) vaccine shows promise for controlling shigellosis. Mucosal administration, particularly nasal and ocular routes, conferred full protection in mice, highlighting a potential new vaccine strategy.
Area of Science:
- Microbiology
- Immunology
- Vaccine Development
Background:
- Shigellosis remains a significant global health concern with no currently available safe and effective vaccine.
- Outer membrane vesicles (OMVs) from Shigella flexneri are being explored as vaccine candidates.
- Adjuvants are crucial for enhancing vaccine efficacy.
Purpose of the Study:
- To evaluate the protective efficacy of a new vaccine composed of Shigella flexneri OMVs encapsulated in poly(anhydride) nanoparticles (NP-OMVs) in a mouse model of shigellosis.
- To assess the impact of different administration routes (intradermal, nasal, ocular, oral) on vaccine-induced protection.
- To investigate the correlation between immune responses (cytokine profiles) and protection.
Main Methods:
- Shigella flexneri OMVs were encapsulated in poly(anhydride) nanoparticles (PMV/MA copolymer).
- BALB/c mice were immunized via intradermal, nasal, ocular, or oral routes with free OMVs or NP-OMVs.
- Mice were challenged intranasally with a lethal dose of Shigella flexneri.
- Protection levels and cytokine production (IL-12p40, IL-10, IFN-γ) were analyzed.
Main Results:
- NP-OMVs administered via nasal and ocular routes provided full protection against lethal Shigella flexneri infection.
- Intradermal administration of NP-OMVs increased protection from 20% (free OMVs) to 100%.
- A strong correlation was observed between a high IL-12p40/IL-10 ratio and protection, with low IFN-γ levels also correlating with protection.
Conclusions:
- Nanoparticle-encapsulated OMVs represent a promising vaccine strategy against Shigella flexneri.
- Mucosal administration routes are particularly effective for inducing protection.
- The adjuvant did not cause adverse effects in the experimental model, suggesting a favorable safety profile.
