干酪乳杆菌细胞壁成分诱导小鼠冠状动脉炎的超抗原机制  

Superantigenic Mechanism of LCWE-induced Coronary Arteritis in Mice

作　　者：覃丽君[1] 范毅敏[1] 牛美真[2] 王宏伟[2] 胡秀芬[2] 康闽[2] 杨杨[2] 王丹丹[2] 隗远祥[2] 李秀云[2] 

机构地区：[1]中山大学附属第二医院儿科,广州510120 [2]华中科技大学同济医学院附属同济医院儿科,武汉430030

出　　处：《华中科技大学学报（医学版）》2008年第4期445-448,共4页Acta Medicinae Universitatis Scientiae et Technologiae Huazhong

基　　金：国家自然科学基金资助项目(No30470645)

摘　　要：目的探讨干酪乳杆菌细胞壁成分(lactobacillus casei cell wall extract,LCWE)诱导小鼠产生冠状动脉炎的超抗原机制。方法4周龄Balb/c小鼠126只,随机分为实验组(63只)和对照组(63只),分别于腹腔注射0.5mlLC-WE或等体积PBS溶液(对照组),注射前及注射后3h、6h、12h、1d、3d、5d、10d、28d分批处死,制备脾单个核细胞悬液,并留取心脏病理标本。检测各组注射前及注射后不同时间小鼠脾单个核细胞TCRVβ2、4、6mAb的表达,以及脾单个核细胞悬液CD4+T细胞CD69的阳性率。结果①病理学检查显示,实验组小鼠冠状动脉炎损害发生率为92.10%,对照组为0,差异有显著性意义。②实验组小鼠在注射LCWE后3h,脾单个核细胞表达TCRVβ2、4、6的CD4+T细胞百分比均明显增加,3d达高峰,其后逐渐消退,注射LCWE后3h、6h、12h、1d、3d、5d、10d与注射前比较及与PBS组比较,差异均有极显著性意义(均P<0.01)。③实验组小鼠脾单个核细胞CD4+T细胞CD69的阳性率,在LCWE注射后3h开始升高(19.32%),12h达高峰(38.80%),以后明显下降,1d为9.89%;与对照组比较,差异均有极显著性意义(均P<0.01)。结论国产LCWE具有超抗原活性特征,可刺激表达TCRVβT细胞的增殖和引起淋巴细胞早期活化。LCWE单次腹腔注射诱导Balb/c小鼠产生的冠状动脉炎病理损害是通过超抗原机制实现的。Objective To investigate the superantigenic mechanism of lactobacillus casei cell wall extract （LCWE） inducing coronary arteritis in mice. Methods 126 4-week-old Balb/c mice were randomized into two groups. Experimental group were injected i.p. with 500 μl of LCWE and the control group with PBS. Then they were sacrificed in batches at 0, 3, 6, 12 h and on the day 1, 3, 5, 10, 28. From each batch, splenic mononuclear cell suspension was collected and cardiac tissues were taken for pathological examination. In splenic mononuclear cells the expression of TCR Vβ2, 4, 6 mAb and the percentage of CD4^＋CD69^＋ T cells were detected from each batch of the two groups. Results ①Pathological examination showed that after the injection of LCWE or PBS, the incidence of histological coronary arteritis in Balb/c mice in the experimental group was significantly higher than in the control group （92.10% vs 0）, ②LCWE stimulated T cells to express TCR Vβ family. After treatment with LCWE, the expression of TCR Vβ2, 4, 6 in splenic mononuclear cells was increased significantly at 3 h, reached the peak value at 3rd day, and then decreased gradually. The levels of TCR Vβ2, 4, 6 expression in the experimental group at 3 h, 6 h, 12 h, 1 d, 3 d, 5 d, 10 d batch were significantly different from that at 0-h and the corresponding batch in control group （P〈0.01）, ③LCWE induced early activation of lymphocytes. In the experimental group, the percentage of CD4＋CD69＋T cells expressed by splenic mononuclear cells was increased at 3 h （19.32%）, and reached the peak value at 12 h （38.80%）, then decreased to 9.89% at 24 h. The levels of CD4^＋CD69^＋ T cell expression in the experimental group were distinctly different from those in the control group （P〈0.01）. Conclusion LCWE made in China possesses superantigenic activity, which can stimulate T cells to express TCR Vβ2, 4, 6 and induce early activation of lymphocytes. Coronary arteritis can be induced by immunization of mice with LCWE injected i.p.

关 键 词：干酪乳杆菌细胞壁成分 TCRVΒ CD69 冠状动脉炎 

分 类 号：R543.3[医药卫生—心血管疾病]