One of the core pathological changes in Broiler Ascites Syndrome (AS) is compensatory hypertrophy of the right ventricle induced by pulmonary hypertension. IRF8 (Interferon Regulatory Factor 8) acts as a repressor regulator of pulmonary vascular remodeling and cardiac hypertrophy, playing an essential role in both pulmonary and cardiovascular remodeling. Currently, few direct studies have been conducted to explore the correlation between the IRF8 gene and the pathogenic mechanism of broiler ascites syndrome. To explore the important role of IRF8 in AS, this study conducted a bioinformatics analysis of IRF8 and employed recombinant gene technology, protein purification, and immunohistochemistry to obtain mouse anti-chicken IRF8 antibodies. The expression of IRF8 was further validated in animals, including broilers and ascites broilers. The results demonstrated that this study successfully prepared and purified a rabbit anti-chicken IRF8 polyclonal antibody. The antibody's titer, specificity, and reactivity were validated using ELISA, Western blot, and indirect immunohistochemistry. The differential expression of IRF8 in key tissues of affected chickens with AS was also analyzed. This polyclonal antibody serves as a reliable tool for detecting, localizing, and studying the function of IRF8. Additionally, it provides an experimental foundation and new insights into understanding the regulatory mechanisms of IRF8 in AS in broilers, aiding in the precise prevention and control of the disease. They further explained the role of IRF8 in pulmonary vascular remodeling during broiler ascites syndrome, thereby establishing a theoretical foundation for investigating the underlying mechanism of IRF8 in this syndrome, identifying potential diagnostic markers, and developing targeted therapies.

To Cite This Article: Cheng S, Liu I, Liu X, Guo X, Gao X, Liu P, Hu G, Hu X and Liu P, 2026. Preparation and functional verification of polyclonal antibodies targeting IRF8 protein in broilers with pulmonary hypertension syndrome. Pak Vet J, 46(6): 1595-1602. http://dx.doi.org/10.29261/pakvetj/2026.151