Infectious bronchitis(IB),a highly contagious acute respiratory disease affecting avian species,poses significant challenges to poultry production.The causative agent,infectious bronchitis virus(IBV),exhibits a high m...Infectious bronchitis(IB),a highly contagious acute respiratory disease affecting avian species,poses significant challenges to poultry production.The causative agent,infectious bronchitis virus(IBV),exhibits a high mutation rate,leading to limited cross-protection by existing vaccines.This necessitates the development of novel vaccines.This study,based on preliminary investigations conducted by our research team,identified six potential strains(PYG QX1,ZQF QX2,FQH QX3,LYZ QX4,XXX QX5,and CSL strains)for vaccine development.Previous pathogenicity test and serum cross-neutralization experiments conducted in this study have demonstrated that the FQH QX3 strain exhibited the weakest pathogenicity and the broadest spectrum of serum neutralization,while the CSL strain showed the highest pathogenicity and was the most challenging to neutralize,posing the greatest difficulty in prevention and control.Subsequently,we constructed and rescued recombinant vaccine candidates,H120-FQH QX3,and H120-CSL,expressing the S1 and N proteins of the FQH QX3 and CSL strains,respectively.Immunization protection experiments indicated that the H120-CSL recombinant vaccine candidate exhibited the most effective immune protection,making it a promising candidate for further study and evaluation as a recombinant vaccine.The S1 and N genes of the CSL strain demonstrated strong immunogenicity,making them potential candidate antigen genes for future vaccine development.展开更多
Infectious bronchitis(IB) is a highly contagious avian disease caused by infection with infectious bronchitis virus(IBV),which seriously affects the development of the global poultry industry. The distribution of TW I...Infectious bronchitis(IB) is a highly contagious avian disease caused by infection with infectious bronchitis virus(IBV),which seriously affects the development of the global poultry industry. The distribution of TW I-type IBV in China has increased in recent years, becoming a widespread genotype. We previously isolated a TW I-type IBV strain termed CK/CH/GD/GZ14 in 2014, but its pathogenicity and possibility for vaccine development were not explored. Therefore, this research aimed to develop a live-attenuated virus vaccine based on the CK/CH/GD/GZ14 strain. The wild type IBV CK/CH/GD/GZ14 strain was serially passaged in SPF embryos for 145 generations. The morbidity and mortality rate of wildtype strain in 14 day-old chickens is 100% and 80% respectively, while the morbidity rate in the attenuated strain was 20%in the 95 th and 105 th generations and there was no death. Histopathological observations showed that the pathogenicity of the 95th and 105th generations in chickens was significantly weakened. Further challenge experiments confirmed that the attenuated CK/CH/GD/GZ14 strain in the 95th and 105 th generations could resist CK/CH/GD/GZ14(5th generation)infection and the protection rate was 80%. Tracheal cilia stagnation, virus shedding, and viral load experiments confirmed that the 95 th and 105th generations provide good immune protection in chickens, and the immunogenicity of the 105th generation is better than that of the 95th generation. These data suggest that the attenuated CK/CH/GD/GZ14 strain in the105th generation may be applied as a vaccine candidate against TW I-type IBV.展开更多
基金supported by National Key R&D Program of China(2022YFD1801000)the Heyuan Branch,Guangdong Laboratory for Lingnan Modern Agriculture Project(DT20220003)+1 种基金the construction project of modern agricultural science and technology innovation alliance in Guangdong province(2023KJ128)Provincial Science and Technology Special Fund Project for Zhongshan City(major special project+ Task list management mode)(2021sdr003).
文摘Infectious bronchitis(IB),a highly contagious acute respiratory disease affecting avian species,poses significant challenges to poultry production.The causative agent,infectious bronchitis virus(IBV),exhibits a high mutation rate,leading to limited cross-protection by existing vaccines.This necessitates the development of novel vaccines.This study,based on preliminary investigations conducted by our research team,identified six potential strains(PYG QX1,ZQF QX2,FQH QX3,LYZ QX4,XXX QX5,and CSL strains)for vaccine development.Previous pathogenicity test and serum cross-neutralization experiments conducted in this study have demonstrated that the FQH QX3 strain exhibited the weakest pathogenicity and the broadest spectrum of serum neutralization,while the CSL strain showed the highest pathogenicity and was the most challenging to neutralize,posing the greatest difficulty in prevention and control.Subsequently,we constructed and rescued recombinant vaccine candidates,H120-FQH QX3,and H120-CSL,expressing the S1 and N proteins of the FQH QX3 and CSL strains,respectively.Immunization protection experiments indicated that the H120-CSL recombinant vaccine candidate exhibited the most effective immune protection,making it a promising candidate for further study and evaluation as a recombinant vaccine.The S1 and N genes of the CSL strain demonstrated strong immunogenicity,making them potential candidate antigen genes for future vaccine development.
基金This study was supported by the Key Research and Development Program of Guangdong Province(2020B020222001)the Construction of Modern Agricultural Science and Technology Innovation Alliance in Guangdong Province(2020KJ128)+5 种基金the Natural Science Foundation of Guangdong Province(2019A1515012006)the National Natural Science Foundation of China(31902252)the Special Project of National Modern Agricultural Industrial Technology System(CARS-41)the National Modern Agricultural Industry Science and Technology Innovation Center in Guangzhou(2018kczx01)the National Key R&D Program of China(2017YFD0502001)the Creation of a Triple Chimeric Vaccine(rIBV-ND-H9)Using Avian Infectious Bronchitis Attenuated D90 as a Vector(2017KZDM008)。
文摘Infectious bronchitis(IB) is a highly contagious avian disease caused by infection with infectious bronchitis virus(IBV),which seriously affects the development of the global poultry industry. The distribution of TW I-type IBV in China has increased in recent years, becoming a widespread genotype. We previously isolated a TW I-type IBV strain termed CK/CH/GD/GZ14 in 2014, but its pathogenicity and possibility for vaccine development were not explored. Therefore, this research aimed to develop a live-attenuated virus vaccine based on the CK/CH/GD/GZ14 strain. The wild type IBV CK/CH/GD/GZ14 strain was serially passaged in SPF embryos for 145 generations. The morbidity and mortality rate of wildtype strain in 14 day-old chickens is 100% and 80% respectively, while the morbidity rate in the attenuated strain was 20%in the 95 th and 105 th generations and there was no death. Histopathological observations showed that the pathogenicity of the 95th and 105th generations in chickens was significantly weakened. Further challenge experiments confirmed that the attenuated CK/CH/GD/GZ14 strain in the 95th and 105 th generations could resist CK/CH/GD/GZ14(5th generation)infection and the protection rate was 80%. Tracheal cilia stagnation, virus shedding, and viral load experiments confirmed that the 95 th and 105th generations provide good immune protection in chickens, and the immunogenicity of the 105th generation is better than that of the 95th generation. These data suggest that the attenuated CK/CH/GD/GZ14 strain in the105th generation may be applied as a vaccine candidate against TW I-type IBV.
