中文摘要：

目的研究枇杷叶三萜酸（TAL）的免疫调节作用。方法以环磷酰胺（Cy）诱导小鼠免疫低下模型，采用碳廓清试验、溶血空斑试验、二硝基氟苯（DNFB）诱导的迟发性超敏反应及T淋巴细胞亚群的测定，观察TAL对免疫低下小鼠非特异性免疫、体液免疫及细胞免疫的影响。结果TAL（75，225，675mg·kg^-1）ig给药能改善Cy诱导的免疫低下小鼠碳廓清指数（K值）和吞噬指数（α值）的降低；提高Cy诱导的免疫低下小鼠血清IgM和IgG的生成，增加Cy诱导的免疫低下小鼠脾细胞溶血素的产生；增强Cy引起的免疫功能低下小鼠的DTH反应。结论TAL具有良好的免疫调节作用。

英文摘要：

Aim To study immunoregulatory actions of triterpene acids loquat leaf（TAL）. Methods To investigate immunoregulatory effects of TAL, phagocytosis mononuclear macrophages （Mφ） were determined with carbon particle clearance test, delayed-type hypersensitivity （DTH） was detected with the degree of ear edema induced by dinitrofluorobenzene （DNFB）, and T cell subsets from spleen in DTH mice were tested by flow cytometry. Meanwhile, spectrophotography was used to estimate levels of IgM and IgG from the serum and spleen in immunosupression mice. Results In different concentrations （75, 225, 675 mg · kg^-1,ig）, TAL significantly improved carbonic clearances of maerophages （pMφ） and the hemolysin level in serum and spleen from inmmunosuppression mice induced by cyelophosphamid （Cy）. DTH, which was suppressed by Cy, was enhanced by TAL （75, 225, 675 mg· kg^-1, ig） in mice. Moreover, results showed that TAL （675 mg · kg^-1, ig） could regulate the off-balance of CD4^ ＋ T and CD8^＋ T cells induced by Cy to the normal level. Conclusion TAL has remarkable immunoregulatory actions.