Innate immunity to adenovirus vectors

描述(申请人提供)：腺病毒载体(Ad)是全世界临床研究中最常见的病毒载体类型。在血管内给药时，Ad会引起多方面的宿主先天免疫和炎症反应，由于剂量有限的全身毒性，这些反应极大地损害了基于Ad的治疗的安全性和有效性。调控这种全身性抗Ad炎症反应的分子和细胞机制仍然知之甚少。通过分析衣壳修饰的重组腺病毒载体在小鼠体内启动炎症反应的过程，我们初步观察到重组腺病毒与23种整合素和巨噬细胞表面受体的相互作用触发了一条由IL-11介导的独特的炎症通路。这一途径的激活启动了下游的细胞因子和趋化素级联反应，这依赖于IL-1RI信号的功能。然而，我们的研究也表明，除了这种细胞因子的产生，静脉注射Ad还可以诱导快速的促炎性MF死亡和促炎的白细胞流入受影响的部位。这项建议的具体目的是为了确定在静脉注射Ad后观察到的临床相关的全身毒性中，每种已知的Ad诱导炎症成分的贡献。在特定的目标1中，我们将探讨在体内介导Ad诱导的促炎性巨噬细胞死亡的分子机制，以及其在激活全身抗Ad炎症反应中的作用。在特定的目的2中，我们将分析静脉注射Ad后聚集在脾和肝内的炎性白细胞的表型标志物和功能激活状态，以及它们在介导急性全身性抗Ad炎症反应中的作用。在具体目标3中，我们将构建避免与23种整合素相互作用的新型Ad载体，并分析它们的体内基因传递和全身毒性。这些研究将提高我们对宿主防御病毒病原体的基本机制的理解，并最终可能导致安全有效的Ad载体的开发，用于治疗广泛的先天和获得性人类疾病。 公共卫生相关性：腺病毒载体(Ad)是全世界临床研究中最常见的病毒载体类型。尽管大量的临床前数据表明Ad在基因转移应用中的应用，但由于血管内注射高剂量(和潜在的治疗性)病毒后产生的危及生命的先天免疫反应和炎症反应，Ad在人类基因治疗中的应用受到严重限制。这一建议是为了填补我们对血管内病毒传递后在体内由Ad诱导的炎症反应的主要理解空白。这些研究将为宿主防御病毒病原体的基本机制提供新的见解，并最终可能导致安全有效的Ad载体的开发，用于治疗广泛的先天和获得性人类疾病。

DESCRIPTION (provided by applicant): Adenovirus vectors (Ad) are the most common viral vector type used in clinical studies worldwide. Upon intravascular delivery, Ad elicits multifaceted host innate immune and inflammatory responses that drastically compromise both the safety and the efficacy of the Ad-based therapy due to a dose-limiting systemic toxicity. The molecular and cellular mechanisms governing this systemic anti-Ad inflammatory response remain poorly understood. By analyzing the initiation of inflammation in vivo after the injection of capsid-modified Ad vectors into mice knockout for critical inflammatory mediators, we have made an original observation that Ad interaction with 23 integrins and macrophage cell-surface receptors triggers a unique inflammatory pathway mediated by IL-11. Activation of this pathway initiates a downstream cytokine and chemokine cascade that depends on functional IL-1RI signaling. However, our studies also indicate that, in addition to this cytokine production, intravenous Ad administration induces a rapid pro-inflammatory MF death and the influx of pro-inflammatory leukocytes into affected sites. The Specific Aims of this proposal are designed to define the contribution of each of the known components of Ad-induced inflammation into the clinically relevant systemic toxicity observed after the intravenous Ad administration. In Specific Aim 1, we will investigate the molecular mechanisms involved in mediating Ad-induced pro- inflammatory macrophage cell death in vivo, and its role in activating systemic anti-Ad inflammatory response. In Specific Aim 2, we will analyze the phenotypic markers and functional activation states of inflammatory leukocytes, accumulating in the spleen and liver after intravenous Ad injection, and their role in mediating the acute systemic anti-Ad inflammatory response. In Specific Aim 3, we will construct novel Ad vectors that would avoid interaction with 23 integrins and analyze their gene delivery and systemic toxicity profiles in vivo. These studies will improve our understanding of the fundamental mechanisms of host defense against viral pathogens and may ultimately lead to the development of safe and effective Ad vectors for the therapy of a wide range of inborn and acquired human diseases. PUBLIC HEALTH RELEVANCE: Adenovirus vectors (Ad) are the most common viral vector type used in clinical studies worldwide. Despite extensive preclinical data on the use of Ad in gene transfer applications, Ad's use for gene therapy in humans is severely limited due to life-threatening innate immune and inflammatory responses that arise after intravascular delivery of the high (and potentially therapeutic) virus doses. This proposal is to fill the major void in our understanding of Ad-induced inflammation in vivo triggered after intravascular virus delivery. These studies will provide new insights into fundamental mechanisms of the host defense against viral pathogens, and may ultimately lead to the development of safe and effective Ad vectors for the therapy of a wide range of inborn and acquired human diseases.