超声微泡造影剂携带PE38生物毒素杀伤血管内皮细胞的实验研究

Experimental study on killing vascular endothelial cells of biological toxin PE38 carried by an ultrasound microbubble contrast-enhanced agent

目的研究超声微泡造影剂PLGA-COOH联合生物毒素PE38对内皮细胞的杀伤效应。方法制备超声微泡造影剂PLGA-COOH,包裹生物毒素PE38后形成复合物,将血管内皮细胞分为空白对照组、辐照微泡组、PE38组、复合物组、辐照复合物组,以TUNEL实验检测凋亡指数,以Western blot实验检测cleaved caspase-3,并进行组间比较。结果 TUNEL结果显示:辐照微泡组细胞凋亡与空白对照组无显著差异(P=0.946);PE38组细胞凋亡较空白对照组显著增加(P<0.001);复合物组细胞凋亡较PE38组显著下降(P<0.001),较空白对照组显著增加(P<0.001);辐照复合物组细胞凋亡较PE38组显著增加(P<0.001)。蛋白检测结果与凋亡检测相符。结论超声造影剂微泡复合物联合生物毒素杀伤血管内皮细胞具有较高的安全性、特异性及有效性,是一种具有前景的肿瘤血管杀伤方法。

Objective To study the killing effect on endothelial cells of biological toxin PE38 carried by an ultrasound microbubble contrast-enhanced agent PLGA-COOH. Methods An ultrasound contrast-enhanced agent PLGA-COOH was prepared and encapsulated biological toxin PE38. The vascular endothelial cells were divided into control group（untreated）, irradiation microbubble group（only added contrast-enhancedultrasound agent, ultrasonic irradiation）, PE38 group（only contained PE38 protein）, compound group（contained microbubble compound, no irradiation） and irradiation compound group（contained microbubble compound, ultrasonic irradiation）. TUNEL was used to test the apoptotic rate. Western blot was used to test the cleaved caspase-3. The results of both tests were compared among groups. Results There was no significant difference between the control group and irradiation microbubble group（P = 0.946）. The apoptotic rate of PE38 group was significantly higher than that of the control group（P 〈0.001）. The apoptotic rate of the compound group was significantly lower than that of the PE38 group（P 〈0.001）, while higher than that of the control group（P 〈0.001）. The apoptotic rate of the irradiation compound group was significantly higher than that of the PE38 group. The results from Western blot assays were similar to that from the TUNEL assays. Conclusion The biological toxin carried by an ultrasound microbubble contrast-enhanced agent has high safety, specificity and effectiveness in killing vascular endothelial cells, and is a promising method in killing tumor blood vessels.