Introduction

Ultrasound-targeted microbubble destruction (UTMD) has been shown a promising approach for target-specific gene delivery and treatment of many diseases in the past decade. To improve the therapeutic potential of UTMD, the gene carrier of microbubbles should possess adequate DNA condensation capability and (or) specific cell or tissue selectivity. The tissue-targeted and ultrasound-targeted cationic microbubbles were developed to meet gene therapy.

Methods

A tissue-targeted stearic acid-inserted cationic microbubbles (SCMBs) were prepared for ultrasound-targeted gene delivery. Branched PEI was modified with stearic acid and further mixed with 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and biot-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000] (ammonium salt) (Biot-DSPE-PEG2000), intercellular adhesion molecule-1 (ICAM-1) antibody and plasmid DNA to prepare cationic microbubbles through ultrasonic hydration. The ICAM-1 antibody and plasmid DNA were expected to assemble to the surface of SCMBs via biotin-avidin interaction and electrostatic interaction, respectively.

Results

It was found that the SCMBs had higher zeta potential compared with neutral microbubbles (NMBs) and cationic microbubbles (CMBs). In contrast, DNA incorporated SCMBs4 showed negative potential, exhibiting good DNA-binding capacity. Confocal images showed that the HeLa cells were attached around by the SCMBs4 from the view of green fluorescence of fluorescein isothiocyanate-loaded IgG which conjugated to ICAM-1 antibody on their surface. After ultrasound treatment, HeLa cells treated with SCMBs exhibited slightly stronger red fluorescence under confocal laser scanning microscope, indicating a synergistic promotion for transfection efficiency.

Conclusions

This tissue- and ultrasound-targeted cationic microbubble demonstrated here showed a promising strategy for improving gene therapy in the future.

中文翻译：

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质粒DNA的组织靶向和超声靶向微泡破坏递送和体外转染。

介绍

在过去的十年中，超声靶向微泡破坏（UTMD）已被证明是一种有前途的靶向特异性基因递送和治疗许多疾病的方法。为提高 UTMD 的治疗潜力，微泡基因载体应具备足够的 DNA 凝聚能力和（或）特定的细胞或组织选择性。开发了组织靶向和超声靶向阳离子微泡以满足基因治疗。

方法

组织靶向硬脂酸插入阳离子微泡 (SCMBs) 被制备用于超声靶向基因传递。支链 PEI 用硬脂酸改性，并进一步与 1,2-二硬脂酰-sn-甘油-3-磷酸胆碱 (DSPC) 和 biot-1,2-二硬脂酰-sn-甘油-3-磷酸乙醇胺-N- [甲氧基（聚乙烯乙二醇）-2000]（铵盐）（Biot-DSPE-PEG2000），细胞间粘附分子-1（ICAM-1）抗体和质粒DNA通过超声波水合制备阳离子微泡。预计 ICAM-1 抗体和质粒 DNA 将分别通过生物素-抗生物素蛋白相互作用和静电相互作用组装到 SCMB 表面。

结果

结果表明，与中性微泡（NMBs）和阳离子微泡（CMBs）相比，SCMBs具有更高的zeta电位。相比之下，掺入 DNA 的 SCMBs4 显示出负电位，表现出良好的 DNA 结合能力。共聚焦图像显示，从负载异硫氰酸荧光素的 IgG 的绿色荧光的角度来看，HeLa 细胞被 SCMBs4 附着在其表面上，该 IgG 与 ICAM-1 抗体结合。超声处理后，用 SCMBs 处理的 HeLa 细胞在共聚焦激光扫描显微镜下表现出稍强的红色荧光，表明对转染效率有协同促进作用。

结论

这里展示的这种组织和超声靶向的阳离子微泡显示了未来改善基因治疗的有希望的策略。