In this project, our team of experts in nanotechnology, vaccines and poultry diseases will test this new technology in a model system with IBV causing infectious bronchitis (IB) disease. Specifically, we start our efforts by First, examine the physico-chemical properties and safety of QAC nanovaccines (Aim I). We hypothesize that QAC will function as a safe and well-tolerated adjuvant system for antigenic proteins used to immunize chickens. To test this hypothesis, we will utilize fluorescently labeled QAC nanovaccines to characterize their physico-chemical properties, antigen release kinetics, cell toxicity and tissue distribution in chickens and chicken embryos. Second, we will decipher the impact of QAC formulas on the immunogenicity of QAC nanovaccines (Aim II). We hypothesize that formulas of QAC-based vaccines will efficiently release IBV antigens throughout the lifespan of broilers (~7 weeks) mediating a robust immune response. To test this hypothesis, IBV-encapsulated by different formulas of QAC will be used to immunize chicks and examine their immunogenicity over 7 weeks. Third, we will Analyze the protective immunity of QAC nanovaccines against challenge with IBV (Aim III). We hypothesize that the QAC nanovaccines will provide a better immunization strategy than commercial modified live vaccines (MLV). To test this hypothesis, we will examine the protective efficacy of QAC-nanovaccines in a standard model system of IBV immunization and challenge in comparison to MLV using readouts that include clinical signs, histology, virus load, and immune responses.