the role of H2-EB1 and AR pathogenesis Objective: To establish the H2-Eb1 knockout model and investigate the H2-EB1 functions in H2-Eb1 knockout mice as a model of AR Methods: The Cre/LoxP system and ES gene knockout technology were applied to create heterozygous H2-Eb1 [ +/- ] knockout mice and their offspring of knockout homozygous [-/-] , heterozygous [ +/- ] and wild type [+/+] H2-Eb1 mice. After identification, offspring of heterozygous [ +/- ] and homozygous [-/-] H2-Eb1 knockout mice were randomly selected to establish AR models to demonstrate the role of H2-Eb1 in AR pathogenesis Conclusion: Our study demonstrated that knockout of H2-Eb1 gene could alleviate mouse AR Symptoms, indicating H2-Eb1 may play an important role in regulating Th1/Th2 balance during the pathogenesis of AR