中文摘要：

目的 研究细粒棘球蚴感染小鼠腹腔巨噬细胞（Mφ）的表型及吞噬功能变化，探索Mφ在宿主应答寄生虫感染中的作用。 方法 将24只6～8周龄雌性BALB/c小鼠随机分为对照组和感染组，每组12只。感染组每只小鼠腹腔注射2 000个原头节。对照组注射等体积PBS。于感染后5个月，收集对照组和感染组小鼠腹腔单核细胞，采用流式细胞术检测Mφ比例及其表面分子CD40、CD80、CD86、主要组织相容性复合体Ⅱ（MHCⅡ）的表达情况；采用中性红吞噬实验检测Mφ密度为1×10^6、5×10^5、1×10^5时的吸光度（A490值），评价其吞噬能力。 结果 对照组和感染组Mφ占单核细胞的比例分别为（20.75±5.91）%和（30.40±3.15）%，感染组高于对照组（P〈0.05）。感染组Mφ表面表达CD40、CD80、CD86、MHCⅡ的比例分别为（45.33±5.51）%、（61.00±10.61）%、（56.88±10.66）%和（27.00±3.82）%，较对照组的（41.43±6.19）%、（59.23±8.65）%、（10.91±1.82）%和（13.67±3.01）%均明显升高（P〈0.05）。感染组Mφ密度为1×10^6、5×10^5、1×10^5时的A490值分别为0.41±0.03、0.24±0.05和0.16±0.01，低于对照组的0.61±0.15、0.47±0.07和0.18±0.01，差异均有统计学意义（P〈0.01）。 结论 感染致小鼠腹腔Mφ吞噬能力下降，但其活化相关表面分子表达上调。

英文摘要：

Objective To investigate the phenotype and phagocytosis changes of the peritoneal macrophages （Mφ） in mice infected with the larval-stage Echinococcus granulosus, and explore the role of Mφ in the responses to parasite infection. Methods Twenty-four female BALB/c mice（age of 6-8 weeks） were randomly assigned into control group and infection group（n=12 in each group）. The mice in the infection group were intraperitoneally injected with 2 000 protoscoleces, while the control mice were injected with equal volume of PBS. Five months after infection, the peritoneal mononuclear cells were collected, and the percentage of Mφ and the expression of surface markers CD40, CD80, CD86, and major histocompatibility complex Ⅱ（MHCⅡ） were determined by flow cytometry. The absorbance（A490 value） of Mφ at different concentrations（1×10^6, 5×10^5, 1×10^5） was determined by the neutral red assay to evaluate the phagocytic ability of Mφ. Results The Mφ constituted（30.40±3.15）% and（20.75±5.91）% in mononuclear cells in the infection and the control groups, respectively. The percentages of Mφ expressing CD40, CD80, CD86, and MHC Ⅱ were（45.33±5.51）%, （61.00±10.61）%, （56.88±10.66）% and （27.00±3.82）% in the infection group, which were all significantly higher than those in the control [（41.43±6.19）%, （59.23±8.65）%, （10.91±1.82）% and （13.67±3.01%）] （P〈0.05）. The A490 values of Mφ at 1×10^6, 5×10^5, 1×10^5 were 0.41±0.03, 0.24±0.05 and 0.16±0.01 in the infection group, which were significantly lower than those in the control （0.61±0.15, 0.47±0.07 and 0.18±0.01）（P〈0.01）. Conclusion The phagocytic ability of peritoneal Mφ is dramatically weakened after infection, but the expression of activation-associated surface markers is significantly up-regulated after infection.