Complement activation in glaucoma

描述（由申请人提供）：我们已经表明，在青光眼视网膜中具有改变表达的主要基因之一是补体成分C1 q。视网膜C1 q在青光眼的DBA/2小鼠模型、激光诱导的猴青光眼和人青光眼中在疾病过程的早期被上调。我们也取得了重大进展，产生一个同源C1 q敲除（KO）菌株的DBA/2的背景下，我们将在未来的研究，以了解C1 q在青光眼中的作用。C1 q和其他补体基因表达的变化表明，神经炎性过程在青光眼视网膜神经节细胞（RGC）病理学中是可操作的。事实上，我们提出的初步证据表明，炎症反应是至关重要的DBA/2小鼠的RGC损失的发展。基于上述和补体在调节适应性免疫中的作用，我们提出了以下关于补体活化如何参与青光眼发病机制的假设：补体活化的中间组分引起RGC轴突和索马损伤。[这种损伤是直接发生还是间接发生（通过对支持细胞、视网膜胶质细胞或免疫细胞和细胞外基质的影响）超出了本项目的范围]。为了验证这一假设，我们必须首先了解许多效应子补体分子中的哪些参与了这一过程。因此，我们提出了以下具体目标：SA 1.检测诱导性和自发性（DBA/2）青光眼小鼠模型的视网膜以及激光诱导的灵长类动物青光眼和青光眼患者标本中中间补体成分的表达水平和/或量的变化。SA 2.通过表征我们在上一个资助期产生的同源DBA/2 C1 q-/-动物的表型，确定通过经典途径的补体激活是否参与疾病的病理生理学。SA 3.确定C4和C3补体成分是否是肿瘤病理发展所必需的。这将通过评估经历激光诱导的IOP升高的同类DBA/2 C4 -/-和C3-/-动物以及C4和C3 KO和野生型动物中的RGC和轴突损失以及神经胶质活化来实现。SA 4.确定C5是否在青光眼的发病机制中具有保护作用。这将通过评估同类DBA/2 C5充足动物以及经历激光诱导的IOP升高的C5科斯和野生型小鼠中的RGC和轴突损失以及神经胶质活化来实现。SA 5.体外测定压力对Muller细胞和RGC补体成分表达的影响。该建议将剖析各种补体成分，以精确确定它们在青光眼发病机制中的作用。研究结果将对其他神经退行性疾病产生更广泛的影响。公共卫生相关性：C1 q和其他补体基因表达的变化表明神经炎性过程在青光眼视网膜神经节细胞（RGC）病理学中起作用。虽然一旦发现了涉及神经退行性变的新途径（在这种情况下是抗补体疗法），就试图引入新的疗法是很有吸引力的，但重要的是首先要充分了解任何干预措施的所有影响，以避免浪费宝贵的资源，甚至可能伤害患者。该建议将解剖各种补体成分，以允许精确确定每一个在青光眼发病机制中的作用，并允许我们合理设计新的治疗方法。

DESCRIPTION (provided by applicant): We have shown that one of the major genes with altered expression in the glaucomatous retina is complement component C1q. Retinal C1q is up-regulated early in the disease process in the DBA/2 mouse model of glaucoma, in laser induced monkey glaucoma and in human glaucoma. We have also made significant progress towards generating a congenic C1q knockout (KO) strain on the DBA/2 background which we will employ in future studies to understand the role of C1q in glaucoma. The changes in expression of C1q and other complement genes, suggest that a neuro-inflammatory process is operational in glaucomatous retinal ganglion cell (RGC) pathology. In fact we present preliminary evidence that an inflammatory reaction is critical for the development of RGC loss in the DBA/2 mouse. Based on the above and the role that complement plays in modulating adaptive immunity we propose the following hypothesis on how complement activation participates in the pathogenesis of glaucoma: Intermediate components of complement activation cause RGC axon and soma damage. [Whether this damage occurs directly or indirectly (through effects on supportive cells, retinal glia or immune cells and extracellular matrix) is beyond the scope of the present project]. To test this hypothesis we must first understand which of the many effector complement molecules are involved in this process. We thus propose the following specific aims: SA1.Test the corollaries that expression levels and/or amounts of intermediate complement components are altered in the retinas from induced and spontaneous (DBA/2) mouse models of glaucoma, as well as in laser induced primate glaucoma and in specimens from patients with glaucoma. SA2. Determine whether complement activation through the classical pathway is involved in the pathophysiology of the disease by characterizing phenotypically the congenic DBA/2 C1q -/- animals we have generated in the previous funding period. SA3. Determine whether the C4 and C3 complement components are required for development of the glaucomatous pathology. This will be achieved by assessing RGC and axonal loss as well as glial activation in congenic DBA/2 C4 -/-and C3-/- animals, as well as in C4 and C3 KO and wild type animals subjected to laser- induced IOP elevation. SA4. Determine whether C5 has a protective role in the pathogenesis of glaucoma. This will be achieved by assessing RGC and axonal loss as well as glial activation in congenic DBA/2 C5 sufficient animals as well as in C5 KOs and wild type mice subjected to laser-induced IOP elevation. SA5. Determine the effect of pressure on Muller cell and RGC complement component expression in vitro. This proposal will dissect the various complement components to allow precise determination of their role in the pathogenesis of glaucoma. Findings will have wider implications for other neurodegenerative disease. PUBLIC HEALTH RELEVANCE: Changes in expression of C1q and other complement genes, suggest that a neuro- inflammatory process is operational in glaucomatous retinal ganglion cell (RGC) pathology. Although it is tempting to try to introduce new therapies once a new pathway involved in neurodegeneration has been identified (in this case anti-complement therapies), it is important to first fully understand all the implications of any intervention in order to avoid wasting valuable resources and potentially even harming patients. This proposal will dissect the various complement components to allow precise determination of the role of each one in the pathogenesis of glaucoma and allow us to rationally design new therapeutic approaches.