Targeted therapy for osteoarthritis

骨关节炎(OA)是普通人群残疾的主要原因，在退伍军人中增加。那里 目前还没有能够预防或改变病程的有效药理制剂。这 该项目将使用一种新的介入性纳米医学方法来预防骨性关节炎。具体地说，我们将使用 靶向抑制物阻断核因子-kappaB的激活及其下游的表达 导致胶原酶-基质金属蛋白酶-13表达的信号转导元件 负责关节软骨中II型胶原的降解。我们的假设是 由核因子B启动并由低氧诱导因子-2α(HIF-2α)传播的信号通路将证明 对早期骨性关节炎非常有效。通过降低基质金属蛋白酶-13，我们将防止II型胶原的不可逆转损失 对大部分的病理负有责任。为了验证我们的假设，我们将使用一种由 内侧半月板不稳定(DMM)。为了预防疾病，我们将使用一种细胞渗透肽(NBD) 这在实验性炎症性关节炎中被证明是有效的。慢性骨性关节炎的严重程度和进展 治疗小鼠的DMM将通过使用诊断性近红外荧光(NIF)的体内成像进行定量 抗II型胶原的单抗(MabCII)，并经关节组织病理学证实。药效的效果 在体内抑制核因子B活化的NBD多肽将在含有核因子B的转基因小鼠身上进行评估 荧光素酶报告基因上游启动子中的反应元件。低氧诱导因子(HIF- 2，由EPAS1编码)被证明与DMM中MMP-13和OA的表达有关 模特。我们将检验这一假说，即核因子B的激活是关节骨关节炎诱导的关键早期点 不稳定和阻止其激活将阻止HIF-2和 最终表达其靶基因，如基质金属蛋白酶MMP13。基因芯片技术的研究进展 来自DMM小鼠膝盖的RNA将被用于发现与核因子B激活有关的基因。建立 使用靶向递送系统抑制关节炎的可行性和有效性我们将使用抗体- 靶向纳米体胶囊，将治疗剂输送到特定的局部部位。纳米小体将成为 使用II型胶原的单抗(MabCII)定位于受损的软骨或 Lyc6抗体用于定位活化的巨噬细胞。MMPs的合成抑制剂已被证明 由于肌肉骨骼疼痛、纤维化和肌腱炎，临床试验中存在问题。我们会克服这个问题的 通过用包装在pH响应性溶液中的抑制剂仅选择性地阻断局部产生的基质金属蛋白酶-13， 内溶智能聚合物纳米粒(SPN)。纳米颗粒的独特之处在于它定位于特定的位置 但在被基质金属蛋白酶-13蛋白分解活性(邻近激活的靶向；PAT)释放之前一直保持包装状态 这是由于在外壳中加入了一种基质金属蛋白酶-13多肽。全面评估发展的方法 并提出了病原菌的致病机制和相关介体的表达。这些实验提供了一种新颖的 管理迄今为止一直是一个棘手问题的方法。

Osteoarthritis (OA) is a major cause of disability in the general population and is increased in Veterans. There are currently no effective pharmacologic agents capable of preventing or altering the course of disease. This project will use a novel interventional nanomedicine approach for preventing OA. Specifically, we will use targeted inhibitors to block activation of nuclear factor kappa B (NF¿B) and expression of the downstream signaling elements that result in expression of matrix metalloproteinase-13 (MMP-13), a collagenase responsible for degradation of type II collagen in articular cartilage. Our hypothesis is that interruption of the signaling pathway initiated by NF¿B and propagated by hypoxia inducible factor-2 alpha (HIF-2¿) will prove extremely effective in early OA. By reducing MMP-13 we will prevent the irreversible loss of type II collagen responsible for much of the pathology. To test our hypothesis, we will use a mouse model of OA induced by destabilization of the medial meniscus (DMM). To prevent disease we will use a cell-permeable peptide (NBD) that has proven effective in experimental inflammatory arthritis. The severity and progression of OA induced by DMM in the treated mice will be quantitated by in vivo imaging using diagnostic near-infrared fluorescent (NIF) monoclonal antibody to type II collagen (MabCII) and confirmed by histopathology of the joints. Efficacy of the NBD peptide to inhibit NF¿B activation in vivo will be evaluated in mice with a transgene containing NF¿B responsive elements in the promoter upstream from a luciferase reporter. Hypoxia-inducible factor (HIF- 2¿, encoded by EPAS1) has been shown to be responsible for expression of MMP-13 and OA in the DMM model. We will examine the hypothesis that NF¿B activation is a critical early point for induction of OA in joint instability and that prevention of its activation will block the downstream induction of expression of HIF-2¿ and ultimately expression of its target genes such as matrix metalloproteinase MMP-13. Microarray analyses on RNA from the DMM mouse knee will be used to discover genes that are linked to NF¿B activation. To establish the feasibility and efficacy of using a targeted delivery system to suppress arthritis we will employ antibody- targeted nanosome encapsulation to deliver the therapeutic agent to specific local sites. Nanosomes will be targeted using a monoclonal antibody to type II collagen (MabCII) for localization to damaged cartilage or antibody to Lyc6 for localization to activated macrophages. Synthetic inhibitors of MMPs have proven problematic in clinical trials due to musculoskeletal pain, fibrosis and tendonitis. We will overcome that problem by selectively blocking only locally produced MMP-13 with an inhibitor packaged within a pH-responsive, endosomolytic smart polymer nanoparticle (SPN). The nanoparticle is unique in that it localizes to specific sites but remains packaged until it is released by MMP-13 proteolytic activity (proximity activated targeting; PAT) due to the incorporation of an MMP-13 peptide in the outer shell. Methods for fully evaluating the development of disease and expression of the mediators involved are proposed. These experiments provide a novel approach to managing what has heretofore been an intractable problem.