Study on the Differences between Infant and Adult Mice during the Development of Oral Tolerance in A Murine Model of Allergic Asthma

• Main Authors: Chi-Ping Liao, 廖季萍
• Other Authors: Bor-Luen Chiang
• Format: Others
• Language: en_US
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/26030201313787901146

碩士 === 國立臺灣大學 === 口腔生物科學研究所 === 98 === Oral tolerance has been defined as the lack of systemic immune response that formerly exposed to the same antigen and this characteristic phenomenon might be used as a potential therapeutic approach for allergic diseases, such as asthma. Several studies indicate that T helper cells in early life induce a strong bias towards Th2 function which plays a role in allergic immune response. DNA methylaion is an important epigenetic regulation involved in regulating gene expression and development of cell lineages. Therefore, in this study we would like to compare the different effects on orally delivered antigen to the murine model of asthma between 3-week-old and 8-week-old mice. In this study, we established the animal model of asthma in adult OVA-TCR transgenic mice. Then oral tolerance was induced by feeding 10 mg/day and 100 mg/day of OVA in 8-week-old mice could suppress the response of asthma, such as airway hyperresponsiveness, antigen specific IgE production and eosinophilia, by contrast, were obviously lower than in all 3-week-old mice groups compared to asthmatic group of 8-week-old mice. The levels of IL-4 produced by splenocyte waslower significantly in all 3-week-old groups which probably prone to the protective Th1 response in early life. Whereas methylation of IL-12 gene promoter occurs in either 3-week-old or 8-week-old mice suggested that is not a main mechanism to decrease the inflammatory response in early life of infant mice. In this study, we demonstrated that 3-week-old mice had less immune response with OVA sensitization. More are needed to clarify the phenomenon, however, mutation of immune system might be different with ages.