Development of Biomaterials that Release Therapeutic Agents to Modulate Inflammat

描述(申请人提供)：这项研究的目标是开发新技术，以减少脊髓损伤后的继发性损伤。目前，对于遭受脊髓损伤的患者，还没有可行的治疗方法。临床上，干预措施包括静脉注射药物。在实验上，大多数干预措施包括静脉或腹膜内注射药物。尽管这些治疗方法改善了功能，但尚未开发出无需泵或通过多次注射即可向受损部位持续输送药剂的技术。在这里，我们提出了一种由琼脂糖和甲基纤维素组成的新型生物材料混合物。先前的初步数据表明，这些混合物在室温下以液体形式存在，并在生理温度下迅速固化。它们可以通过注射器注射，以便于在受伤部位使用。在这一修订的应用中，我们提出的数据显示，谷胱甘肽和白介素10可以分别在体外释放5天和6天。这种水凝胶是在冷冻环境中仅使用含水缓冲液制造的。因此，负载的试剂不会受到苛刻的加工条件的影响，并且在释放后应该起作用。数据显示，释放的谷胱甘肽能够保护分离的鸡背根神经节神经元免受Fenton反应产生的自由基的影响。同时，用白介素10酶联免疫吸附试验检测水凝胶释放的白介素10。对大鼠脊髓损伤模型进行了一项初步研究，其中负载了白细胞介素10和谷胱甘肽的水凝胶。初步数据显示，与单纯注射水凝胶相比，加载治疗药物的水凝胶在损伤后42天有更高的BBB评分。本文描述了将荧光化学物质罗多明与谷胱甘肽和白介素10偶联的技术。荧光标记也将在目标1中得到确认。在目标2中，该提案概述了与俄亥俄州立大学菲利普·波波维奇博士的合作研究经验。开发的水凝胶随后将应用于俄亥俄州立大学开发的大鼠脊髓损伤模型。在那里的工作将确定治疗的急性体内释放，急性和慢性炎症反应的缓解，病变体积和神经元保留的慢性评估，以及运动恢复的慢性评估。公共卫生相关性：目前给药以减少脊髓损伤后继发性损伤的技术包括静脉注射或腹膜内注射。利用生物材料，由琼脂糖和甲基纤维素制成的水凝胶可以在持续的一段时间内装载减少二次伤害的试剂。这项建议中描述的研究将确定在大鼠脊髓损伤模型中，负载谷胱甘肽或白细胞介素10的水凝胶在减少继发性损伤方面比注射这些药物更有效。

DESCRIPTION (provided by applicant): The goal of this study is to develop new technology to reduce secondary injury following spinal cord injury. Currently, there are no viable treatments for patients who have sustained spinal cord injury. Clinically, interventions involve injection of agent intravenously. Experimentally, most interventions involve injection of agent intravenously or intraperiotoneally. Although these treatments have improved functionality, technology has not yet been developed to supply continuous delivery of agents to the damaged site without the need of pumps or through the administration of several injections. Here, we present a novel biomaterial blend composed of agarose and methylcellulose. Prior preliminary data has shown that these blends exist as a liquid at room temperature and quickly solidify at physiological temperatures. They are injectable through a syringe for ease of application to an injured site. Within this revised application, we present data showing that glutathione and interleukin-10 can be released for five and six days in vitro respectively. The hydrogel is fabricated in a chilled environment using just aqueous buffers. Thus, loaded agents are not subjected to harsh processing conditions and should be functional after release. Data shows that released glutathione is able to protect dissociated chick DRG neurons from free radicals produced by the Fenton reaction. Also, interleukin-10 released from the hydrogel was detected by an interleukin-10 ELISA. A pilot study was conducted where hydrogel loaded with interleukin-10 and glutathione were injected into a rat spinal cord injury model. Preliminary data show that hydrogel loaded with therapeutics had higher BBB scores 42 days post-injury compared to those injected with just plain hydrogel. In aim one of this proposal; techniques are described to couple the fluorescent chemical rhodomine to both glutathione and interleukin-10. Fluorescent conjugation will also be confirmed in aim 1. In aim two; the proposal overviews a collaborative research experience with Dr. Phillip Popovich at Ohio State. Hydrogels developed will then be applied to a rat spinal cord injury model developed at Ohio State. Work there will determine the acute in vivo release of therapeutic, acute and chronic mitigation of the inflammatory response, chronic assessment of lesion volume and neuronal sparing, and chronic assessment of locomotor recovery. PUBLIC HEALTH RELEVANCE: Current techniques to administer agents to reduce secondary injury following spinal cord trauma involve intravenous or intraperiotoneally injection. Using biomaterials, hydrogels made from agarose and methylcellulose can be loaded with agents that reduce secondary injury for a sustained period of time. The research described in this proposal will determine if hydrogels loaded with glutathione or interleukin-10 are more effective at reducing secondary injury than injection of these agents in a rat spinal cord injury model.