Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands; Center for Imaging Research and Education (CIRE), Eindhoven, The Netherlands.
Nijmegen Center for Mitochondrial Disorders, Radboud University Medical Centre, Nijmegen, The Netherlands.
J Control Release. 2014 Dec 10;195:130-7. doi: 10.1016/j.jconrel.2014.06.033. Epub 2014 Jun 28.
Localized gene delivery has many potential clinical applications. However, the nucleic acids (e.g. pDNA and siRNA) are incapable of passively crossing the endothelium, cell membranes and other biological barriers which must be crossed to reach their intracellular targets. A possible solution is the use of ultrasound to burst circulating microbubbles inducing transient permeabilization of surrounding tissues which mediates nucleic acid extravasation and cellular uptake. In this study we report on an optimization of the ultrasound gene delivery technique. Naked pDNA (200 μg) encoding luciferase and SonoVue® microbubbles were co-injected intravenously in mice. The hindlimb skeletal muscles were exposed to ultrasound from a non-focused transducer (1 MHz, 1.25 MPa, PRI 30s) and injection protocols and total amounts as well as ultrasound parameters were systemically varied. Gene expression was quantified relative to a control using a bioluminescence camera system at day 7 after sonication. Bioluminescence ratios in sonicated/control muscles of up to 101× were obtained. In conclusion, we were able to specifically deliver genetic material to the selected skeletal muscles and overall, the use of bolus injections and high microbubble numbers resulted in increased gene expression reflected by stronger bioluminescence signals. Based on our data, bolus injections seem to be required in order to achieve transient highly concentrated levels of nucleic acids and microbubbles at the tissue of interest which upon ultrasound exposure should lead to increased levels of gene delivery. Thus, ultrasound mediated gene delivery is a promising technique for the clinical translation of localized drug delivery.
局部基因传递有许多潜在的临床应用。然而，核酸（例如 pDNA 和 siRNA）不能被动地穿过内皮细胞、细胞膜和其他生物屏障，这些屏障必须穿过才能到达其细胞内靶标。一种可能的解决方案是使用超声破坏循环微泡，诱导周围组织的瞬时通透性，从而介导核酸外渗和细胞摄取。在这项研究中，我们报告了超声基因传递技术的优化。将编码荧光素酶的裸 pDNA（200μg）和 SonoVue®微泡静脉内共注射到小鼠中。后腿骨骼肌用非聚焦换能器（1MHz，1.25MPa，PRI 30s）进行超声照射，并且系统地改变了注射方案和总剂量以及超声参数。在超声处理后 7 天，使用生物发光成像系统相对于对照定量基因表达。在超声处理/对照肌肉中获得了高达 101×的生物发光比值。总之，我们能够将遗传物质特异性地递送到选定的骨骼肌中，并且总体而言，使用推注注射和高微泡数量导致基因表达增加，反映出更强的生物发光信号。基于我们的数据，似乎需要推注注射以在感兴趣的组织中达到短暂的高浓度核酸和微泡水平，而在超声暴露下，这应该会导致基因传递水平的增加。因此，超声介导的基因传递是将局部药物传递临床转化的有前途的技术。
