Infectious Bronchitis Virus Infection of Chicken: The Essential Role of Mucosal Immunity

A low-endotoxic Salmonella enterica Gallinarum serovar delivers infectious bronchitis virus immunogens via a dual-promoter vector system that drives protective immune responses through MHC class-I and -II activation in chickens

“…Upon vaccination, elevated levels of antigen-specific IgY antibodies reflect maturation of antibody-secreting B cells, which regulate humoral immune responses. Similarly, the induced secretory IgA plays a pivotal role in mucosal immunity by limiting the spread of IBV on the mucosal surfaces of the respiratory tract, restricting the virus to the systemic circulation ( Ganapathy, 2021 ). Antigen-delivering Salmonella invades APCs, where the IBV antigens are processed and presented to MHC class II, mediating T cell–dependent IgA secretion ( Griffin and McSorley, 2011 ; Reboldi and Cyster, 2016 ).…”

Radix Isatidis polysaccharide (RIP) resists the infection of QX-type infectious bronchitis virus via the MDA5/TLR3/IRF7 signaling pathway

“…Infectious bronchitis virus ( IBV ) belongs to the family Coronaviridae , the genus Gammacoronavirus , and has been classified into a number of different serotypes that cause acute and highly contagious disease in chickens, causing huge losses to the poultry industry ( Kong et al., 2021 ; Zamzam et al., 2022 ; Zhang et al., 2022 ). Studies have shown that the main clinical signs of infectious bronchitis ( IB ) include coughing, sneezing, breathlessness, open-mouth breathing, rales, and depression, and that IBV can affect the respiratory tract, kidneys, oviducts, ovaries, heart, liver, and bursa of chickens ( Ganapathy, 2021 ; Al-Rasheed et al., 2022 ; Gallardo et al., 2022 ). Due to incomplete proofreading mechanism of the coronavirus’ RNA polymerase and gene recombination during genome replication, new variants or recombinant IBV strains are constantly emerging, complicating the development of appropriate control programs.…”