Institute for Biochemistry, Westfälische Wilhems Universität,Münster, Wilhelm Klemm Str. 2, 48149 Münster, Germany.
J Control Release. 2018 Sep 10;285:172-177. doi: 10.1016/j.jconrel.2018.07.016. Epub 2018 Jul 10.
The main obstacle for the treatment of brain diseases is the restriction of the passage of pharmaceuticals across the blood-brain barrier. Endothelial cells line up the cerebral micro vessels and prevent the uncontrolled transfer of polar substances by intercellular tight junctions. In addition to this physical barrier, active transporters of the multi-drug-resistance prevent the passage of hydrophobic substances by refluxing them back to the blood stream. This paper reviews the development and selected applications of an in vitro porcine brain derived primary cell culture system established in the authors lab that closely resembles the BBB in vivo and could thus be used to study beyond other applications drug delivery to the brain. An essential technique to control the intactness or destruction of the barrier, the impedance spectroscopy, will be introduced. It will be shown that nanoparticles can cross the blood brain barrier by two mechanisms: opening the tight junctions and thus allowing parallel import of substances into the brain as well as receptor mediated endocytosis using brain specific target molecules. However cytotoxic effects have to be considered as well which beside standard cytotoxicity assays could be also determined by impedance technology. Moreover it will be shown that enzymes e.g. for enzyme replacement therapy could be transferred across the barrier by proper tuning or chemical modification of the enzyme. Since this review is based on a conference presentation it will mainly focus on applications of the monoculture system developed in the authors lab which under given culture conditions is useful due to its easy availability, robustness, good reproducibility and also due to its simplicity. Improvements of this model made by other groups will be acknowledged but not discussed here in detail.
治疗脑部疾病的主要障碍是药物穿过血脑屏障的限制。内皮细胞排列在脑微血管上，并通过细胞间紧密连接防止极性物质的不受控制的转移。除了这种物理屏障外，多药耐药的主动转运体通过将疏水性物质反流回血流中来防止它们的通过。本文回顾了作者实验室建立的体外猪脑原代细胞培养系统的发展和选定应用，该系统与体内 BBB 非常相似，因此可用于研究药物向大脑的传递等其他应用。本文将介绍一种重要的技术，即阻抗谱，用于控制屏障的完整性或破坏。将表明纳米颗粒可以通过两种机制穿过血脑屏障：打开紧密连接，从而允许物质平行进入大脑，以及使用大脑特异性靶分子进行受体介导的内吞作用。但是，必须考虑细胞毒性作用，除了标准细胞毒性测定外，还可以通过阻抗技术来确定。此外，本文还将表明，通过适当调整或化学修饰酶，可以将酶等用于酶替代疗法的酶转移穿过屏障。由于这篇综述是基于会议演讲，因此它将主要侧重于作者实验室开发的单核细胞培养系统的应用，在给定的培养条件下，由于其易于获得、稳健性、良好的重现性以及简单性，该系统非常有用。其他小组对该模型的改进将得到承认，但这里不会详细讨论。
