A Protein Biologic for the Treatment of Sepsis

描述（由申请方提供）：脓毒症和相关多器官功能障碍是死亡和发病的主要原因，在美国每年造成超过215000例死亡。尽管对脓毒症的病理机制的了解不断增加，但治疗选择仍然主要限于抗生素，糖皮质激素和支持措施。广泛的共识是，线粒体功能障碍，所谓的细胞病变性缺氧，在脓毒症的过程中发展，并成为该过程的晚期阶段的定义特征。细胞病理性缺氧的特征在于线粒体复合物I、ATP产生和氧消耗的可逆抑制，其导致免疫抑制和广泛的器官衰竭。 已经发现实验操作，例如增强线粒体生物发生的转录因子（例如线粒体转录因子A，TFAM）的过表达，在脓毒症模型中有效，但是临床应用由于缺乏适当强大的药理学生物发生刺激物而受到阻碍。 Gencia开发了一种重组形式的人TFAM（rhTFAM），经过修饰使其能够穿过细胞屏障并特异性地导入线粒体。注射后，rhTFAM进入到目前为止检查的所有组织中的线粒体，并作为转录因子，迅速（在数小时内）增加复合物I活性，耗氧量，线粒体质量和最大ATP输出高达150%，同时减少ROS的产生。用rhTFAM实现的线粒体生物发生刺激的幅度、速度和持久性大于文献中描述的任何药理学试剂。在行为上，用rhTFAM治疗的健康小鼠将跑步耐力（转棒潜伏期）增加了300%，并且即使在34个月大的小鼠中，在长达10个月的给药期间也没有显著的副作用。初步的LPS脓毒症动物模型实验显示用rhTFAM治疗的小鼠的存活率显著提高。 在该I期SBIR项目中，我们将测试rhTFAM是否能够逆转在脓毒症的LPS模型中观察到的细胞病变性缺氧。本项目的具体目标是：1）确定rhTFAM处理是否改善LPS攻击的HepG 2和人原代肝细胞中的炎症、线粒体功能和细胞死亡 2)确定rhTFAM处理是否改变用LPS攻击的c57/bl 6小鼠的死亡率。 证实rhTFAM在脓毒症LPS模型中的有益作用将为II期SBIR工作铺平道路，其中rhTFAM将用于脓毒症CLP（盲肠结扎和穿刺）模型。 公共卫生相关性： 根据该提案进行的目标将显示rhTFAM作为脓毒症治疗的可行性。脓毒症是对感染和其他严重应激源的全身性炎症反应，是ICU环境中死亡的主要原因，在美国每年造成215，000例死亡。尽管对脓毒症的病理机制的了解不断增加，但治疗选择仍然主要限于抗生素，糖皮质激素和支持措施。

DESCRIPTION (provided by applicant): Sepsis and related multiple organ dysfunction are a major cause of mortality and morbidity, responsible for over 215 000 deaths per year in the US. Despite growing understanding of the pathomechanism of sepsis, treatment options are still limited primarily to antibiotics, glucocorticoids, and supportive measures. There is wide consensus that mitochondrial dysfunction, so called cytopathic hypoxia, develops over the course of sepsis, and becomes the defining feature of the late stage of the process. Cytopathic hypoxia is characterized by a reversible suppression of mitochondrial complex I, ATP production and oxygen consumption which result in immunosuppression and widespread organ failure. Experimental manipulations, such as overexpression of transcription factors that enhance mitochondrial biogenesis (e.g. the mitochondrial transcription factor A, TFAM), have been found effective in models of sepsis but clinical applications are hampered by lack of suitably powerful pharmacological biogenesis stimulators. Gencia developed a recombinant form of human TFAM (rhTFAM), modified to allow it to traverse cellular barriers and to be specifically imported into mitochondria. After being injected rhTFAM enters mitochondria in all tissues examined so far and acts as a transcription factor, rapidly (within hours) increasing complex I activity, oxygen consumption, mitochondrial mass and maximum ATP output by up to 150%, while decreasing ROS production. The magnitude, speed and persistence of mitochondrial biogenesis stimulation achieved with rhTFAM are larger than with any pharmacological agents described in the literature. Behaviorally, healthy mice treated with rhTFAM increased running endurance (rotarod latency) by 300%, and there were no significant side-effects over up to 10 months of dosing even in mice aged 34 months. Preliminary LPS sepsis animal model experiments show significantly improved survival in mice treated with rhTFAM. In this Phase I SBIR project we will test whether rhTFAM is capable of reversing of the cytopathic hypoxia observed in an LPS model of sepsis. Specific aims of the project are: 1) Determine if rhTFAM treatment ameliorates inflammation, mitochondrial function, and cell death in HepG2 and human primary liver cells challenged with LPS 2) Determine whether rhTFAM treatment alters mortality in c57/bl6 mice challenged with LPS. Confirmation of a beneficial effect of rhTFAM in LPS models of sepsis would pave the way for Phase II SBIR work where rhTFAM would be used in the CLP (cecal ligation and puncture) model of sepsis. PUBLIC HEALTH RELEVANCE: The aims carried out under this proposal will show feasibility for rhTFAM as a treatment for Sepsis. Sepsis is a systemic inflammatory response to infection and other severe stressors, and is the leading cause of death in the ICU setting, responsible for 215,000 fatalities per year in the US. Despite growing understanding of the pathomechanism of sepsis, treatment options are still limited primarily to antibiotics, glucocorticoids, and supportive measures.