中文摘要：

目的探讨多房棘球绦虫（Em）重组Bb-EmⅡ／3-Eml4．3．3疫苗免疫和Em原头节攻击后小鼠脾CD4＋和CD8＋T淋巴细胞亚群的变化。方法用重组Bb-EmⅡ／3-Em14．3．3疫苗分别通过皮下注射、肌肉注射、鼻腔黏膜接种以及口服接种免疫BALB／c小鼠，双歧杆菌（Bb）液和磷酸盐缓冲液（PBS）为对照，12周后，用50个Em原头蚴腹腔注射进行攻击，攻击感染18周剖杀小鼠，检获泡球蚴组织，称取重量，计算减蚴率；分离脾细胞，流式细胞仪检测脾CD4＋和CD8＋T淋巴细胞亚群的百分比。结果疫苗免疫组（皮下注射、肌肉注射、鼻腔黏膜接种、口服接种）小鼠检获泡球蚴重量[（0．77±0．52）、（0．87±0．60）、（2．17±0．50）、（3．06±0．15）g]均明显低于PBS对照组[（3．54±0．32）g．P〈0．05或〈0．01]。疫苗免疫组（皮下注射、肌肉注射、鼻腔黏膜接种、口服接种）小鼠脾CD4＋T细胞亚群[（28．2±2．5）％、（25．0±2．7）％、（24．0±1.3）％、（23．0±1．8）％]显著高于PBS对照组[（16．1±2．2）％，P均〈0．01]；各疫苗免疫组小鼠CD8＋T细胞亚群水平均轻微升高，但组间比较差异无统计学意义（F=1．36，P〉0．05）。皮下注射组小鼠CD4＋T细胞亚群高于肌肉注射组、鼻腔黏膜接种组和口服接种组（P均〈0．05）。结论CD4＋T细胞亚群在Em重组Bb-EmⅡ／3-Em14-3-3疫苗诱导的小鼠抗Em原头节攻击感染的保护性免疫机制中起关键作用，疫苗皮下注射是一种较好的免疫途径。

英文摘要：

Objective In order to investigate the changes of T lymphocytes subsets in mice immunized with recombinant Bb-EmⅡ/3-Em14-3-3 vaccine of Echinococcus muhilocularis （Em） and challenged with Em protoscoleces. Methods BALB/c mice were immunized with recombinant Bb-EmⅡ/3-Em14-3-3 vaccine by subcutaneous injection, intramuscular injection, nasal mueosa inoculation and oral administration, Bifidobacterium （Bb） and PBS were used as controls. After 12 weeks of immunization, all the mice were challenged with 50 protoscoleces of Em by intraperitoneal injection. Eighteen weeks later, mice were killed to measure alveolar hydatid weight and spleens were taken to separate spenocytes, in which the percentages of CD4＋ and CD8＋ T cell subsets were determined by flow cytometry. Results Alveolar hydatid weight was （0.77 ± 0.52）, （0.87 ± 0.60）, （2.17 ± 0.50）, （3.06 ± 0.15） g in subcutaneous injection, intramuscular injection, nasal mucosa inoculation and oral administration groups, respectively, which was obviously lower than that in PBS control group [（3.54 ± 0.32） g, P 〈 0.05 or 〈 0.01]. The level of CD4＋ T cell subset was （28.2± 2.5）%, （25.0 ± 2.7）%, （24.0 ±1.3）%, （23.0 ± 1.8）% in subcutaneous injection, intramuscular injection, nasal mucosa inoculation and oral administration groups, respectively, which was significantly higher than that in PBS control group [（16.1 ± 2.2）%, all P 〈 0.01]. The level of CD8＋ T cell subset in the immunization groups was slightly elevated, but there was no statistical significance between groups （F= 1.36, P〉 0.05）. The level of CD4＋ T cell subset in subcutaneous injection group was higher than that in intramuscular