经口感染弓形虫诱导小鼠黏膜免疫动物模型的建立

Establishment of mice model that induces mucosal immunity by oral infection of Toxoplasma gondii

目的建立经口感染弓形虫速殖子诱导黏膜免疫的动物模型。方法BALB/c小鼠分别灌胃接种5×103、5×104、5×105、5×106个RH株速殖子,观察小鼠的体况、病理变化;检测肠道分泌型IgA(SIgA)和Peyer’spatches(PP)淋巴细胞及小肠上皮内淋巴细胞(IEL)T细胞亚群的变化。结果经口接种5×104个弓形虫RH株速殖子可使小鼠出现临床症状和病理改变;SIgA水平升高;黏膜诱导部位的CD4+T亚群及效应部位的CD8+T亚群水平升高。结论5×104个弓形虫RH株速殖子灌胃接种小鼠可以诱导机体黏膜免疫应答。

Objective To establish mice model that induces mucosal immunity by orally infected tachyzoites of Toxoplasma gondii. Methods Respectively, 5×103, 5×104, 5×105, 5×106 tachyzoites of RH strain were inoculated to BALB/c mice by stomach delivery. The control group was given PBS solution. Symptoms and pathological changes of mice were observed. Secretory im-munoglobulin A (SIgA) was assayed. The lymphocytes from Peyer's patches (PP) and intraepithe-lial lymphocyte (IEL) were observed and the changes of CD4+ and CD8+ T cells assayed by SABC immunohistochemistry. Results Inoculation of 5×104 tachyzoites of Toxoplasma gondii caused symptoms and pathological changes in mice. The titre of SIgA increased in intestine, and CD4+ T subset of the mucosal inductive sites and CD8+ T subset of the mucosal effectors' sites increased. Conclusion Mucosal immunity may be induced by oral infection of 5×104 tachyzoites of T. gondii RH strain in BALB/c mice.