摘要
利用51Cr-标记血小板检测其与内皮细胞粘附功能;ELISA方法检测血管内皮细胞表面玻璃连接蛋白受体(VnR)表达改变;Fura-2/Am负载测定群体细胞胞浆游离钙;Fluo-3/Am负载测定单细胞内游离钙等方法,观察了肿瘤坏死因子(TNF)对内皮细胞(EC)与血小板粘附功能的影响,发现TNF-α(100U/ml)可明显促进血小板(PL)与EC的粘附,cpm值明显高于对照组(410.7±17.6vs.219.7±16.3n=6P<0.01).用抗VnR-β3亚单位的单抗(McAb)可大部分阻断TNF-α的促粘附作用,与未加单抗的TNFα组相比有显著差异,非McAb组cpm为410.5±17.6,McAb组为288.3±13.8,(n=6,P<0.01),用ELISA法证实不同浓度TNF-α(200U/ml~1000U/ml)可增加内皮细胞表面VnR表达,以1000U/ml组为最明显。同一浓度TNF-α组,VnR的表达呈现随作用时间延长而增加的趋势。此外,TNF-α可增加EC[Ca2+]i,群体细胞和单个细胞测定的结果一致。以上结果提示,TNF-α可增加EC与血小板的粘附功能,其作用机制是以VnR-(αvβ3?
The effect of tumor necrosis facto-α(TNF-α) on the adhesion of ECs (endothelial cells)to platelets(PLs)and its mechanism was observed.The change of adhesion of ECs to PLs,the expression of vitronectin receptor(VnRe.g.integrin αVβ3)on the surface of ECs and the change of[Ca2+]i of mass-ECs and sigle EC were studied.It was found that cpm-value of TNF α-treated group was much higher than that of control group.(410.7±17.6 vs. 219.7±16.3 n=6 P<0.01).Anti-β3 monoclonal-antibody(McAb SZ-22)did block the main effect of TNFα-indrced adhesion of PLs to ECs.The cpm were 410.5±17.6 in TNFα+nonMcAb group and 288.3±13.8 in TNFα+McAb group (n=6 P<0.01).It was proved by ELISA method that different concentrations of TNFα(200U/ml-1000U/ml) could increase the expression of αVβ3 on the surface of EC and the most remarkable change was found in 1000U/ml group.In the same concentration group,the expression of VnR showed a up-regulated tendency with the stimulating time.In addition,TNFα indrced [Ca2+]i increase was consistant with both the mass-cell and single-cell.These results suggested that TNFα may strenthen the adhesive function of EC to PL,that the vitronection receptor (VnR,e.g,integrin αVβ3)involves in this vechanism as a main medium,via Ca^2+ as a second-messager.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
1997年第5期470-474,共5页
Chinese Journal of Pathophysiology
基金
国家自然科学基金