Nanomedicine Development for Systemic Lupus Erythematosus

摘要 该项目的总体目标是开发一种高效安全的治疗系统性狼疮的纳米药物 红斑性狼疮（SLE）或狼疮。在狼疮临床治疗中使用的许多药物中，糖皮质激素 (GC)由于其高抗炎效力而被最广泛地使用。但它们臭名昭著的毒性 阻碍了长期的临床应用。为了减少它们的副作用，我们将地塞米松 (Dex，一种有效的GC）与N-（2-羟丙基）甲基丙烯酰胺（HPMA）共聚物，并发现Dex前药 在狼疮性肾炎小鼠模型（NZB/WF 1）中是亲肾性的。预防和治疗已建立的 狼疮性肾炎，每月注射P-Dex（i. v.）在预防和减少 白蛋白尿的治疗效果优于每日等量游离地塞米松治疗。P-Dex治疗没有引起骨质疏松症， 但其他GC副作用（如肾上腺萎缩）仍然存在。为了进一步应对这一挑战，我们最近 设计了一种新的前药纳米药物，通过将Dex与聚乙二醇（PEG）结合。所得 两性PEG-Dex自组装成胶束。当在NZB/W F1小鼠中进行测试时， 有效的治疗效果，类似于P-Dex，但没有显示出任何典型的GC副作用。基于这些 令人兴奋的初步数据，我们假设，由于其不同的结构设计，P-Dex和PEG-Dex， 具有非常不同的药代动力学/生物分布（PK/BD）特征和与细胞相互作用的模式， 免疫系统的组成部分，导致不同的亚细胞分布/激活模式，类似 治疗效力，但不同的安全性。我们还推测，我们的原始结构设计 主要候选者PEG-Dex胶束由于异质性，在其他狼疮模型中可能并不总是起作用 和狼疮疾病的合并症，这将需要进一步的结构优化。来验证这些 假设，我们建议首先进行PEG-Dex和P-Dex的头对头比较PK/BD研究。 我们还将分析从两种前药纳米药物释放的游离Dex的PK/BD概况。这些 研究可以部分解释为什么PEG-Dex胶束具有比P-Dex更低的毒性，并将说明其工作原理。 从PK/BD的角度研究其作用机制。其次，我们将进行体外和体内细胞研究， 并分析P-Dex和PEG-Dex与免疫系统各种细胞成分的相互作用 以及它们对前药纳米药物的生物学功能的影响。这项研究的结果将 进一步解释了为什么PEG-Dex在细胞和分子水平上显示出比P-Dex更好的安全性。 第三，我们将在NZM 2410、MRL/lpr和CIA小鼠中验证PEG-Dex胶束的有效性和安全性，因为 狼疮疾病的异质性和共病性在这些模型中重现。基于 通过实验反馈，PEG-Dex胶束的结构将得到优化，并得到最终药物 将在NZB/W F1小鼠中评价候选物1年，以确认其在以下方面的长期疗效和安全性： 准备临床翻译。

ABSTRACT The overall goal of this project is to develop a highly effective and safe nanomedicine for systemic lupus erythematosus (SLE) or lupus. Among many medications used in clinical management of lupus, glucocorticoid (GC) is most widely used because of their high anti-inflammatory potency. But their notorious toxicities have hampered the long-term clinical application. To reduce their side effects, we have conjugated dexamethasone (Dex, a potent GC) to N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer and found that the Dex prodrug is nephrotropic in a mouse model of lupus nephritis (NZB/W F1). Prophylactic and treatment of established lupus nephritis with a monthly P-Dex injection (i.v.) are much more effective in prevention and reduction of albuminuria than dose equivalent daily free Dex treatment. The P-Dex treatment did not elicit osteoporosis, but other GC side effects (e.g. adrenal gland atrophy) remained. To further address this challenge, we recently designed a novel prodrug nanomedicine by conjugating Dex to polyethylene glycol (PEG). The resulting amphiphilic PEG-Dex self-assembles into micelles. When tested in the NZB/W F1 mice, it demonstrated potent therapeutic efficacy, similar to P-Dex, but did not show any classical GC side effects. Based on these exciting preliminary data, we hypothesize that due to their different structural design, P-Dex and PEG-Dex have very different pharmacokinetic/biodistribution (PK/BD) profiles and patterns of interaction with the cellular components of the immune system, leading to distinct subcellular distribution/activation patterns, similar therapeutic potency, but different safety profiles. We also speculate that the original structural design of our lead candidate, PEG-Dex micelle may not always work as well in other lupus models due to the heterogeneity and comorbidities of lupus disease, which would necessitate further structure optimization. To validate these hypotheses, we propose first to perform a head-to-head comparative PK/BD study of PEG-Dex and P-Dex. We will also analyze the PK/BD profiles of the free Dex released from the two prodrug nanomedicine. These studies may partially explain why PEG-Dex micelle has lower toxicity than P-Dex and will illustrate its working mechanism from the PK/BD aspect. Second, we will perform in vitro and in vivo cellular studies to compare and analyze the interaction of P-Dex and PEG-Dex with various cellular components of the immune system and their impact on the biological functions of the prodrug nanomedicine. The results from this study will further explain why PEG-Dex shows much better safety profile than P-Dex on the cellular and molecular levels. Third, we will validate PEG-Dex micelle's efficacy and safety in NZM2410, MRL/lpr and CIA mice because of the heterogeneity and comorbidities of lupus disease recapitulated in these models. Based on the experimental feedback, the structure of PEG-Dex micelle will be optimized and the resulting final drug candidate will be evaluated in NZB/W F1 mice for 1 year to confirm its long-term efficacy and safety in preparation for its clinical translation.