Fate of siRNA in the lungs and optimization of siRNA inhalant formulation based on RNA interference effect

我们开发了Cy5.5-siRNA，使我们能够在不影响其RNA干扰作用的情况下追踪siRNA在体内的命运。向siRNA中加入载体可以延长siRNA在肺中的滞留时间，抑制siRNA进入血液。与全身给药相比，肺部局部给药siRNA减少了表达RNA干扰效应所需的siRNA量。考虑到Cy5.5-siRNA在体内的稳定性，我们开发了一种新的电泳方法，使用PCI溶液分离siRNA和Cy5.5。本研究获得的结果将极大地促进基于siRNA在体内命运的siRNA制剂的发展。

We developed Cy5.5-siRNA, that enable us to trace the fate of siRNA in a body without affecting its RNA interference effect. Adding a vector to siRNA increased the retention time of siRNA in the lungs and suppressed siRNA entering into blood. The local pulmonary administration of siRNA reduced the amount of siRNA required to express the RNA interference effect compared to the systemic administration. Regarding to the stability of Cy5.5-siRNA in a body, we developed a novel electrophoresis method that separates siRNA and Cy5.5 by using a PCI solution. The results obtained by this study will contribute greatly to the development of siRNA formulations based on the fate of siRNA in the body.