A self-adjuvanted nanoparticle based vaccine against infectious bronchitis virus

Area of Science:

• Veterinary immunology
• Vaccine development
• Poultry health

Background:

• Infectious Bronchitis Virus (IBV) poses a significant threat to poultry health, impacting respiratory, renal, and reproductive systems.
• Existing live attenuated and killed IBV vaccines face challenges in efficacy.
• There is a need for innovative vaccine strategies to control IBV outbreaks.

Purpose of the Study:

• To develop and evaluate a novel vaccine candidate against Infectious Bronchitis Virus (IBV).
• To assess the immunogenicity and protective efficacy of a Self-Assembling Protein Nanoparticle (SAPN) vaccine displaying IBV epitopes and flagellin.

Main Methods:

• A novel vaccine, IBV-Flagellin-SAPN, was engineered using Self-Assembling Protein Nanoparticle (SAPN) technology, presenting IBV spike protein B cell epitopes and flagellin.
• Chickens were immunized with IBV-Flagellin-SAPN, a control construct, or buffer, followed by challenge with the IBV M41 strain.
• Humoral immune responses (antibody titers) and cellular immune responses (peripheral mononuclear cell proliferation) were measured.
• Tracheal virus shedding and lesion scores were assessed post-challenge.

Main Results:

• Chickens immunized with IBV-Flagellin-SAPN exhibited high antibody responses.
• Ex vivo proliferation tests showed a significantly higher stimulation index in peripheral mononuclear cells from IBV-Flagellin-SAPN immunized chickens.
• Immunization with IBV-Flagellin-SAPN resulted in a significant reduction in tracheal virus shedding and decreased tracheal lesion scores compared to controls.

Conclusions:

• The IBV-Flagellin-SAPN vaccine candidate demonstrates significant immunogenicity and protective efficacy against IBV challenge.
• The Self-Assembling Protein Nanoparticle (SAPN) platform, combined with flagellin adjuvant, is a promising approach for developing effective IBV vaccines.
• This novel vaccine holds potential as a viable alternative to current Infectious Bronchitis Virus (IBV) vaccination strategies.