登革2型病毒调控血管内皮细胞凝血及抗凝系统相关蛋白的表达

DV_2 regulate the expression of coagulant and anti-coagulant proteins in human vein endothelial cells

目的观察登革2型病毒(DV2)对脐静脉血管内皮细胞(HUVECs)表达组织因子(TF)、组织因子抑制物(TFPI)和血栓调节蛋白(TM)的影响。方法应用胰酶消化HUVECs并进行传代培养,用生长良好的第二、三代细胞进行试验。应用CCK-8测定DV2感染对细胞活性的影响;应用逆转录聚合酶链反应(RT-PCR)检测细胞内TF、TFPI和TMmRNA水平。结果DV2对细胞活力的影响与对照组相比差异无统计学意义。DV2感染HUVEC后6h,TFPI mRNA水平显著下调(P<0.05),48h恢复到正常水平。TF mRNA对照组不表达,DV2组各时相均有微量表达。而DV2组抗凝蛋白TMmRNA表达显著高于对照组(F=17.855,P=0.000),24h达到峰值(P<0.05),以后渐下降,72h正常表达。结论DV2急性下调TFPI mRNA和微量上调TF mRNA表达,启动外源性凝血途径,促进血液凝固;但DV2诱导高水平的TM可有效地增强抗凝活性,这有利于出血和血浆外渗。结果提示DV可诱导血管内皮细胞所调控的凝血系统失调,这可能在登革出血热/登革休克综合征(DHF/DSS)的出血机制中起重要作用。

Objective To elucidate the effects of Dengue virus on the expression and secretion of tissue factor（TF）, tissue factor inhibitor（PAI-1） and thrombomodulin （TM） in vein endothelial cells. Methods Cultured human umbilical vein endothelial cells（HUVECs） were infected by DV2 for different hours. Cell viability was then determined by CCK 8 assay, and lactate dehydrogenase（LDH） in mitochondria of HUVECs was measured to assess cell activity. Cytoplasmic RNA of HUVECs was extracted by Trizol method and TF, TFPI and TM mRNA levels was assayed by reverse transcript polymerase chain reaction（RT-PCR）. Results DV2（MOI=2） did not produce cell toxicity as shown by cell viability according to LDH determination in culture media. DV2 infection inhibited the TFPI mRNA expression （P 〈 0.05） within infection 6 h, but the inhibition effect weakened as time past, and was up to the normal level until 48 h, but DV2 infection did not elevate the level of TF mRNA in HUVECs significantly. While TM mRNA level in DV2 group was enhanced noticeably comparing to control group （P 〈 0.05）, and TM mRNA level of DV2 group reached the peak after infected 24 h, then began to descend. After infected 72 h, the TM mRNA level recovered normal level. Conclusion DV2 pro motes the expression of TM mRNA in HUVECs, which inhibits thrombin activity, and shifts the local balance tending to increased anticoagulant capacity in blood. Such shift may increase hemorrhage risk, which may play an important role in the pathogenic development of DHF/DSS.