幽门螺杆菌感染对LAIR-1影响的实验研究

Experimental study on the expression of LAIR-1 induced by Helicobacter pylori

目的通过构建小鼠感染模型,研究幽门螺杆菌(Hp)感染对白细胞相关免疫球蛋白样受体-1(LAIR-1)表达的影响。方法将32只C57BL/6小鼠随机分为对照组和感染组。感染组通过Hp菌液灌胃建立小鼠感染模型,对照组以PBS灌胃。6周后处死小鼠,采用胃黏膜分离培养、革兰染色、PCR及生化反应检查Hp定植情况,采用流式细胞术检测小鼠外周血单个核细胞(PBMC)中单核细胞和淋巴细胞表面LAIR-1的表达。结果感染组小鼠Hp感染率为91.3%(21/23)。感染组和对照组小鼠PBMC中单核细胞比例分别为(22.85±3.56)%和(49.85±0.35)%,淋巴细胞比例分别为(40.93±10.05)%和(30.15±0.35)%,差异均有统计学意义(t=5.845和2.137,P<0.05)。感染组和对照组小鼠PBMC表面LAIR-1表达率分别为(70.16±7.75)%和(83.4±0.1)%,淋巴细胞表面LAIR-1表达率分别为(56.81±11.37)%和(72.3±0.6)%,差异均有统计学意义(t=3.761和2.491,P<0.05)。结论 Hp感染下调了小鼠PBMC中单核细胞及LAIR-1的表达,上调淋巴细胞比例但下调其LAIR-1的表达。

Objectives To analyze the changes caused by Helicobacter pylori infection in mononuclear cells isolated from the peripheral blood of the mice and to analyze the leukocyte-associated immunoglobulin-like receptor-1（LAIR-1）molecules expressed on the surface of those cells. Methods Thirty-two C57BL/6 mice were randomly divided into a negative control group and an H.pyloriinfection group.The H.pyloriinfection group was administered a bacterial suspension of H.pylori and the control group was administered PBS.After 6weeks of administration,all of the mice were sacrificed.Levels of LAIR-1expression on the surface of peripheral blood mononuclear cells（PBMCs）were then analyzed with flow cytometry.Isolates from the gastric mucosa were identified as H.pylori via several methods,such as culturing of gastric mucosa,Gram staining,PCR,and biochemical reactions. Results Of the strains isolated from the infection group,91.3%（21/23）were identified as H.pylori.The percentage of monocytes in mice infected with H.pylori decreased to 22.85±3.56% while that percentage was 49.85±0.35%in mice administered PBS（P〈0.05）.However,the percentage of lymphocytes in mice infected with H.pylori increased to 40.93±10.05% while that percentage was 30.15±0.35%in mice administered PBS（P〈0.05）.The rate of LAIR-1expression on monocytes in mice infected with H.pylori decreased to 70.16±7.76% while that rate was 83.4±0.1%in mice administered PBS（P〈0.05）.The rate of LAIR-1expression in lymphocytes infected with H.pylori also decreased（56.81±11.37%）in comparison to the rate in mice administered PBS（72.3±0.6%,P〈0.05）. Conclusion Both the percentage of monocytes in PBMCs and the expression of LAIR-1decreased in mice infected with H.pylori.In contrast,infection with H.pylori resulted in a higher percentage of lymphocytes but a lower level of LAIR-1expression.