Ox-LDL促进CD4^＋T细胞Notch3、Notch4的表达及其意义

Ox-LDL promotes the expression and significance of Notch3 and Notch4 in CD4^＋ T cells

目的探讨氧化低密度脂蛋白（OX—LDL）对人CD4^＋T细胞Notch3、Notch4表达的影响。方法采用密度梯度离心法分离健康人外周血单个核细胞，分离淋巴细胞，经流式细胞术分选CD4^＋T细胞，然后分为空白对照组、低、中、高剂量组，加入浓度分别为0mg／L、50mg／L、100mg／L、200mg／L的OX—LDL培养72h，流式细胞术检测CD4^＋T细胞Notch3、Notch4分子的表达变化。结果流式细胞术检测显示，空白对照组、低、中、高剂量组的Notch3表达分别为（3．42±0．36％）、（16．98±1．05％）、（9．83±0．52％）、（15．65±0．96％）。与空白对照组比较，低、中、高剂量组Notch4表达率明显升高，差异有统计学意义（P〈0．01）。空白对照组，低、中、高剂量组的Notch4表达分别为（9．54±0．72％）、（29．33±2．29％）、（13．58±1．43％）、（36．62±3．27％）。与空白对照组比较，低、高剂量组Notch4表达率明显增高，差异有统计学意义（P〈0．01）。结论ox-LDL能明显促进人外周血CD4^＋T细胞Notch3、Notch4的表达，可能与T细胞分化的精细调节和炎症反应的负调节有关，参与动脉粥样硬化的发生、发展。

Objective To observe the effect of oxidized low-density lipoprotein（ox-LDL） on the expression of Notch3 and Notch4 in human peripheral blood CD4＋ T cells. Methods Density gradient centrifugation was used to separate the peripheral blood mononuclear cells from healthy people, and the CD4＋ T cells were sorted by flow eytometry. Tcells were divided into four groups： the blank control group, low, medium and high concentration group, and coeuhure with ox-LDL. The concentration of ox-LDL was 0 mg/L, 50 mg/L, 100 mg/L and 200 mg/L respectively. The expression of Notch3 and Notch4 in CD4＋ T cells was detected by flow cytometry in each group ＇after 72 h. Results The results revealed that the expression of Notch3 in each group was 3.42±0.36%, 16.98±1.05%, 9.83±0.52% and 15.65±0.96% respectively. Compared with the blank control group, the expression of Notch3 in other groups were significantly increased, the difference was statistically significant （P 〈 0.01 ）. The expression of Notch4 in each group was 9.54±0.72%, 29.33±2.29%, 13.58±1.43% and 36.62±3.27% respectively. Compared with the blank control group, the expression of Notch4 was significant increased, and the differences were statistically significant （P 〈 0.01 ）. Conclusion Ox-LDL can significantly promote the expression of Notch3 and Notch4 in human peripheral blood CD4＋ T cells, which may be related to the fine regulation of T cell differentiation and the negative regulation of inflammatory reaction, and is involved in the occurrence and development of atherosclerosis.