摘要
目的观察登革2型病毒(DV2)对人脐静脉血管内皮细胞(HUVEC)表达组织纤溶酶原激活物(tPA)和纤溶酶原激活物抑制物1(PAI-1)的影响. 方法应用胰酶消化分离HUVEC并进行传代培养,用生长良好的第2、3代细胞进行试验.用cell counting kit-8(CCK-8)测定DV2感染后细胞活性变化;发色底物法测定感染DV2组和对照组培养液中tPA、PAI-1活性;RT-PCR检测细胞内tPA和PAI-1 mRNA水平. 结果 DV2感染对细胞活力的影响与对照组相比差异无统计学意义.感染DV2组培养液中tPA活性在12～72 h显著升高(P＜0.05);DV2诱导HUVEC表达tPA mRNA的水平显著上调,12 h达到峰值,以后渐降,72 h mRNA表达水平仍高于对照组(P＜0.01).而DV2感染组培养液中PAI-1活性和PAI-1 mRNA的表达与对照组比较差异无统计学意义(P＞0.05). 结论 DV2感染可显著上调HUVEC的tPA mRNA转录,增强内皮细胞tPA蛋白的分泌,而不影响PAI-1 mRNA的转录或改变内皮细胞PAI-1的分泌.结果提示DV2可活化但并不损伤内皮细胞,诱发内皮细胞增强表达纤溶酶原激活物而致使纤溶系统失衡,引起纤溶亢进,这可能是诱发DHF/DSS患者急性期出血、低血容量性休克等体征的主要因素之一.
Objective To elucidate the effects of dengue virus on the expression and secretion of tissue plasminogen activator （ tPA ） and plasminogen activator inhibitor type - 1 （PAI - 1 ） in endothelial cells. Methods Cultured human umbilical vein endothelial cells（HUVEC） were infected with DV2. Cell viability was then deterrained by CCK-8 assay, tPA, PAI-1 activity in the media was assayed by fibrin overlay and reverse fibrin antograph. Level of cytoplasmic PAI-1 and tPA mRNA was measured by reverse transcript-polymerase chain reaction （RT-PCR）. Restllts DV2 has no cell toxicity as shown by cell viability according to LDH determination in culture media, tPA activity of DV2 group is enhanced（ P 〈0.05）, and PAI-1 activity of DV2 group remains normal level. Moreover, DV2 infection induces a marked increase of the levels of tPA mRNA till to 12 h, then began to descend but down to the normal level till to 72 h. However, DV2 infection did not change the level of PAI-1 mRNA in HUVEC（ P 〉 0.05）. Conclusion DV2 has no cell toxicity, but can promote the expression of tPA mRNA, increase activity of tPA but does not change PAI-I mRNA expression. The time-dependent increase in the DV2 induced tPA mRNA expression and activity can shift the local balance to an increase fibrinolytic state in blood, which raise increase hemorrhage risk, and play an important role in the pathogenesis of DHF/DSS.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2005年第7期523-528,共6页
Chinese Journal of Microbiology and Immunology
基金
广东省医学科研基金资助(A2005340)
