Effects of an immune tolerogenic vaccination on the prevention of allergic asthma in a mouse model / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate whether immunization mice with an immune tolerogenic vac-cine could inhibit the occurrence of allergic asthma through regulating the inflammatory T cells . Methods The BALB/c mice were randomly divided into 5 groups, with 10 mice per group.The mice in different groups were treated with different immunization strategies , which were 100 μl of phosphate buffer ( PBS) for the negative control , 10 μg of ovalbumin for the unrelated antigen control , 10 μg of dexametha-sone for group 3, 10μg of ovalbumin protein and 10μg dexamethasone for group 4 and 100 μg of ovalbumin protein and 100 μg of dexamethasone for group 5.The mice were immunized subcutaneously on days 1, 4, 7, and 14.Seven days after the last immunization , all mice were used for the induction of allergic asthma . The incidences of asthma in mice from different groups were evaluated 24 hours after the induction .The eval-uation indicators included pathological changes in lung tissues , infiltration of inflammatory cells in bronchial alveolar lavage fluid , antibody in serum samples and allergic responses .Results Immunization mice with the immune tolerogenic vaccine significantly reduced the infiltration of inflammatory cells in lung tissues , de-creased the levels of IgE and IgG 1 antibodies in serum samples and alleviated the injuries and pathological changes in lung tissues.However, the percentages of CD4+CD25+Foxp3+regulatory T cells to CD4+T popu-lations were significantly increased .Moreover, immunization mice with the tolerogenic vaccine could inhibit the expression of Th2 type cytokines .Conclusion Immunization mice with the tolerogenic vaccine could in-duce high levels of regulatory T cells , reduce the infiltration of inflammatory T cells in lung tissues and in-hibit the expression of Th2 cytokines, resulting in the inhibited occurrence of asthma in the murine model .