中文摘要：

为研究含pLAO的重组耻垢分枝杆菌疫苗（Recombinant Mycobacterium smegmatis，rM．S）对小鼠的保护作用。将重组耻垢分枝杆菌疫苗pLAO（MS）2×10^7灌胃免疫接种BALB／c小鼠，同时设PBS组、耻垢分枝杆菌空菌组，免疫4周后，各组处死一批小鼠，取胃组织待用；余下的小鼠用幽门螺杆菌标准株（Helicobacter pylori SS1，Hp SS1）攻击2次，4周后处死小鼠，进行胃组织快速尿素酶试验、Hp培养、炎症程度及其炎症活动度评分，以评价疫苗对胃黏膜Hp感染的免疫保护作用，ELISA检测Up特异性血清IgG和IgA水平。结果表明疫苗组Hp定植评分均明显低于PBS组和空菌组，疫苗组不仅可以降低Hp的定植，而且能减轻UP造成的小鼠胃黏膜的局部慢性炎症反应。免疫后BALB／c小鼠特异性抗体显示rM．S疫苗诱导的Hp特异性血清IgG、IgA水平都升高。因此rM．S疫苗经灌胃接种BLAB／c小鼠能降低Hp定植，减轻胃黏膜的炎症反应，对Hp感染有明显的预防保护作用。

英文摘要：

In the present study, we evaluated the protective efficacy of pLAO （Ms） in the mice model. The rM.S （2 × 10^7） was administered orally to the BALB/c mice with gastric tube, while control groups of mice were administered PBS and M.smegmatis, respectively. Batches of mice in each group were killed 4 weeks after immnization and stomach were collected for sampling. The remaining mice were challenged twice with H.pylori SSI and then killed 4 weeks later. The immunoprotection of the gastric mucosa against H.pylori infection were evaluated by the rapid urea assay, H.pylori cultivation and gastritis score. The levels of the H.pylori specific serum IgG and IgA were detected by ELISA. The results showed that the H.pylori colonization of the immunized group was much lower than that of the PBS and the M.smegmatis groups. Relive of the local chronic inflammation of the mice gastric mucosa was also observed in the immunized group. The specific serum IgA and IgG were significantly induced by rM.smegrnatis. Therefore intragastric administration of rM.smegrnatis could be used as an effective means for prevention of H.pylori infections.