Abbas Rami, Fatemeh Kazemi-Lomedasht, Ali Mirjalili, Mojtaba Noofeli, Fereshteh Shahcheraghi* and Naser Mohammadpour Dounighi*
Background: Outer membrane vesicles (OMVs) release from Gram-negative bacteria and are interesting alternatives that can replace those vaccines that contain naturally incorporated bacterial surface antigens, lipopolysaccharides (LPS) and outer membrane proteins (OMPs). Nanoparticles can be used to encapsulate vesicles for slow release and prevent macromolecular degradation.
Objective: Therefore, encapsulation of OMVs of B. pertussis into sodium alginate nanoparticles was the main aim of the current study.
Method: The OMVs of B. pertussis extracted and characterized by particle sizer, electron microscopy, SDSPAGE and Western blot assays. The extracted OMVs were encapsulated in sodium alginate nanoparticles (OMV-NP) using unique gelation process and injected into BALB/c mice. Immunogenicity indices such as different classes of antibodies and interleukins related to different T cell lines were evaluated in immunized mice by ELISA. The respiratory challenge was evaluated in the groups of mice. The existence of pertussis toxin (PTX), filamentous haemagglutinin (FHA) and PRN (pertactin) in B. pertussis OMVs was verified using SDS-PAGE and Western blot analysis.
Results: TEM electron microscopy showed the size of these OMVs to be around 20-80 nm. The OMVs with appropriate quality were encapsulated into sodium alginate nanoparticles (OMV-NP), and the final size was about 500 nm after encapsulation. Immunity indices were significantly higher in the OMV-NP receiving group. In challenge tests, the OMV-NP vaccine was able to show the highest rate of lung clearance compared to the control groups (OMV and wPV) at the lowest injection dose.
Conclusion: The results indicate the potential of OMV-NP as a novel vaccine delivery system.
OMV, Sodium alginate, Bordetella pertussis, Nanoparticle, Vaccine. Nano-Delivery, Nano-Vaccine
Bacteriology Department, Pasteur Institute of Iran, Tehran, Biotechnology Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Biotechnology Department, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Human Bacterial Vaccine Department, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Bacteriology Department, Pasteur Institute of Iran, Tehran, Venomous animals Department and Human Sera, Razi Vaccine & Serum Research Institute, Karaj