Functionalization of LbL-Microcarriers as Drug Delivery System for Elastase Inhibitors and HOCl Scavengers for the Termination of Chronic Inflammation

慢性炎症的治疗代表了现代世界的重要医学挑战。全身作用药物的应用通常伴随着多种副作用。因此，开发新的药物递送系统必须考虑靶向和局部持续应用的药物，具有高效率和减少的副作用。层层（LbL）涂层微载体代表了一个很好的选择，用于治疗局部炎症发生，例如，在关节炎关节。构建的模块化原理，即带相反电荷的聚电解质逐步吸附到球形微模板上，形成用于整合活性剂的多层，提供了许多优点：使用生物相容性和可生物降解的聚合物，可以实现一种或多种活性剂的时间控制和持续释放，特异性细胞靶向和高生物相容性。本提案的主题是继续概念发展和研究那些特定的载体，这些载体涉及将炎症物质转运到发炎组织中。在这里，中性粒细胞是研究的焦点：这些免疫细胞持续产生大量的侵袭性酶，这些酶有助于慢性化和大规模组织破坏。一种特殊的酶，弹性蛋白酶，在这些过程中起着重要作用。为了有效抑制，LbL微载体将被设计为仅通过一种方法促进α 1抗胰蛋白酶（AT）对细胞内和细胞外弹性蛋白酶的抑制。此外，LbL微载体的模块化结构将用于提供一种以上的活性剂，但具有不同的释放动力学：中性粒细胞也释放活性氧物质（ROS）以及HOCl，导致AT的活性丧失。因此，HOCl清除剂头孢哌酮将被整合到多层中以维持AT活性。在这个提议中，将研究多层或模板内两种试剂的组装顺序对它们的细胞内和细胞外功能的影响。与另一种药物传递系统，细胞穿透肽（CPP）和AT的复合物的直接比较，应有助于建立LbL微载体的优势。此外，还将研究LbL微载体的摄取行为和吞噬溶酶体加工，以及额外的脂质层表面修饰。这种修饰是一种有趣的平台，用于功能分子（抗体，CPP）或活性剂的特异性结合，尽管多层包埋活性剂的可用性和释放曲线仍然未知。预计所获得的数据将支持新的和高度特异性的药物递送系统的开发，特别是通过使用逐层技术的多功能属性。

The treatment of chronic inflammation represents an important medical challenge in the modern world. The application of systemically acting pharmaceuticals is often accompanied by multiple side effects. Therefore, the development of new drug delivery systems has to consider targeted and locally sustained applications of pharmaceuticals with high efficiency and reduced side effects.Layer by Layer (LbL) coated microcarriers represent an excellent choice for the treatment of local inflammations occurring, for instance, in arthritic joints. The modular principle of construction, that is the step-wise adsorption of oppositely charged polyelectrolytes onto a spherical micro-template forming a multilayer for an integration of active agents, offers many advantages: Using biocompatible and biodegradable polymers, time controlled and sustained release of one or more active agents, specific cell targeting and high biocompatibility can be realized. The subject of this proposal is to continue the conceptual development and investigation of those specific carriers regarding the transport of antiinflammatory substances into inflamed tissues. Here, neutrophils are in the focus of the investigations: These immune cells generate continuously considerable amounts of aggressive enzymes which contribute to chronification and massive tissue destruction. A specific enzyme, elastase, plays a major role in these processes. For an effective inhibition, LbL microcarriers will be designed to promote intracellular and extracellular elastase inhibition by a1antitrypsin (AT) by only one approach. Additionally, the modular construction of LbL microcarriers will be used to provide more than one active agent, but with different release kinetics: Neutrophils also release reactive oxygen species (ROS) as well as HOCl leading to the activity loss of AT. Therefore, an HOCl scavenger, cefoperazone, will be integrated into the multilayer to maintain AT activity. In this proposal, the influence of the assembling sequence of both agents within the multilayer or template on their intra and extracellular functionality will be investigated. The direct comparison with another drug delivery system, complexes of Cell Penetrating Peptide (CPP) and AT, should help to establish the advantages of LbL microcarriers. Additionally, the uptake behavior and phagolysosomal processing of the LbL microcarriers with regard to an additional lipid layer surface modification will be studied. This modification is an interesting platform for the specific binding of functional molecules (antibodies, CPP) or active agents although the availability and release profiles of the multilayer-embedded active agents are still unknown. It is expected that the obtained data will support the development of new and highly specific drug delivery systems, particularly by using the multifunctional attributes of Layer by Layer technology.