免疫小鼠及正常小鼠巨噬细胞对利什曼无鞭毛期的吞噬作用

内脏利什曼原虫主要寄生在巨噬细胞系统的单核吞噬细胞内,在一般情况下其无鞭毛期能抵抗巨噬细胞的杀灭作用。 为了观察经杜氏利什曼原虫免疫后的小鼠其巨噬细胞的作用,我们采用了CFW纯系小鼠,经不同免疫方法于免疫后不同时间观察了体外培养中巨噬细胞的吞噬功能。实验采用的巨噬细胞与杜氏利什曼原虫前鞭毛期的比例为1:4。从每24小时吞噬功能的结果表明,经利什曼鞭毛体纯抗原免疫及福氏佐剂加利什曼抗原免疫的两组小鼠,均以免疫后3周的吞噬率最高,分别为72％及96％;两组吞噬指数的均值±SD(4.46±1.72,6.99±4.36)亦较正常组小鼠(1.68±1.25,1.72±1.15)为高,并具有显著差异(P<0.05)。提示了特异性抗原以及与佐剂合并具有对吞噬功能的激活作用。实验并观察了巨噬细胞内利什曼原虫无鞭毛期的活力作用,从吞噬原虫后20小时开始至 144小时,正常小鼠巨噬细胞内的无鞭毛期再经三恩氏培养基培养后均能恢复为前鞭毛期,而经免疫小鼠巨噬细胞内的利什曼原虫无鞭毛期在72小时后即消失活力。 另外,对小鼠腹腔巨噬细胞吞噬利什曼原虫的动态亦作了仔细观察。 实验结果说明了经过免疫的小鼠,由于被淋巴细胞激活后的巨噬细胞能杀死利什曼原虫,巨噬细胞在宿主对感染应答中是一个重要部分,对于探索黑热病的免疫机理具有一

THE PHAGOCYTOSIS OF AMASTIGOTES OF LEISHMANIA DONOV ANE BY MACROPHAGES FROM NORMAL AND IMMUNE MICE

Leishmania is an intracellular parasite of mononuclear phagocytes. The amastigote form of the parasite is capable of resist the microbicidal activity of macrophages.CFW inbred mice was used through out the experiments. For phagocytosis test macrophages and promastigotes were mixed in the ratio of 1 to 4. Reading was made after 24 hrs incubations. The results showed that higher phagocytic rates (72%,96%) were obtained in those 2 groups of mice immunized 3 weeks ago with promastigotes antigen alone or antigen plus Freund's complete adjuvant(FCA). The mean of phagocytic rate is significantly higher in immunized groups than in the normal controls. (P<0.05 using the Student t test)The activity of phagocytosis by normal macrophage of the amastigotes transformed normally into promastigotes in the culture, but the amastigotes disappeared 72 hrs after phagocytosis by immunized macrophages.From a series of in vitro studies it has been found that macrophages from "immune" animals can phagocytose and lyse amastigotes, but those from non-immune animals are unable to kill engulfed parasites which multiply in the host cells.Maerophage appears to be an important component in the host's response to Kala-azar infection.