Pharmacological inhibition or genetic deletion of a neurotoxin found abundantly at sites of spinal cord injury will neuroprotect and improve outcome.

对脊髓损伤部位大量发现的神经毒素进行药理学抑制或基因删除将起到神经保护作用并改善预后。

• 批准号: MR/X003752/1
• 负责人: Elizabeth Bradbury
• 金额: $ 75.63万
• 依托单位: King's College London
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FX003752%2F1
• 关键词: Pharmacological; inhibition; genetic; deletion; neurotoxin

Background:Spinal cord injuries or brain injuries disable millions of people each year, and the cost to national economies run into tens of billions of pounds. Therapies which reduce the extent of neural cell death after injury and that improve survivor outcomes are badly needed.Innovation: We have discovered a neurotoxic molecule that is found abundantly at sites of neurotrauma in humans, rats, and mice after it is released by white blood cells (including neutrophils). Per molecule, it is up to 700 times more neurotoxic than glutamate (a molecule which is toxic at high concentrations when released from injured neurons). Pharmaceutical companies have spent hundreds of millions of pounds trying to develop medicines that inhibit toxins like glutamate; given our discovery of this even more potent neurotoxin at sites of neurotrauma, it merits urgent attention and could be a highly valuable target. Surprisingly, this neurotoxin remains essentially unstudied after neurological injury. Excitingly, we have identified a polyclonal antibody which completely blocks this molecule's ability to kill CNS neurons for at least 48 hours in vitro.Aim 1: We wish to develop therapeutic "monoclonal antibodies" that inhibit this neurotoxin. "Monoclonal antibodies" are a class of therapeutic that can be extraordinarily effective at inhibiting defined molecular targets; they are amenable to engineering for specific properties (e.g., size, longevity in the body, safety profile) and already provide health and commercial benefits worldwide. We now seek to develop and evaluate novel monoclonal antibodies that improve survival of human and rodent CNS neurons exposed to this neurotoxin in Petri dishes (Aim 1 and 2) or in vivo (Aim 3). Aim 2: We have also discovered that cerebrospinal fluid obtained by lumbar puncture from humans within 48 hours of spinal cord injury is toxic to rodent CNS neurons cultured in Petri dishes; we now wish to maximise survival of injured human neurons in Petri dishes by applying our new therapeutic antibodies without, or combined with, inhibitors of other toxins (e.g., glutamate and reactive oxygen species). We will analyse any other residual toxic molecule(s) by separating cerebrospinal fluid into component parts (e.g., based on molecular charge or size), for identification using modern biochemical methods, including but not limited to proteomics. Aim 3: We wish to test the idea that injection of these therapeutic monoclonal antibodies by lumbar puncture (into the cerebrospinal fluid) in mice would improve outcome in a clinically relevant model of contusive spinal cord injury when given in a medically feasible time frame. We predict that short-term treatment with the therapeutic monoclonal antibodies will neutralize this neurotoxin, will improve survival of human CNS neurons, and will improve sensorimotor outcomes (e.g., walking) in the long-term. Alternatively, we will evaluate whether lumbar injection of a known human protein inhibitor of this toxin can improve outcome. Aim 4: Finally, we wish to determine whether mice that lack the mouse equivalents of this neurotoxin show better CNS cell survival and improved recovery in the same clinically relevant model of contusive spinal cord injury. This will enable us to confirm the specificity of our therapeutic monoclonal antibodies, and their mechanisms of action, which in turn will help us optimise our therapy for maximum benefit.Clinical importance: These experiments are important because monoclonal antibodies could be given by straightforward lumbar puncture, within hours of injury, to reduce the amount of disability after spinal cord injury, and potentially also after stroke or traumatic brain injury.These experiments will help us take this potential therapy one step closer to clinical trials.

背景：脊髓损伤或脑损伤每年导致数百万人残疾，国民经济损失高达数百亿英镑。迫切需要减少损伤后神经细胞死亡程度并改善幸存者预后的疗法。创新：我们发现了一种神经毒性分子，白血释放后，在人类、大鼠和小鼠的神经损伤部位大量存在。细胞（包括中性粒细胞）。每个分子的神经毒性比谷氨酸（一种从受损神经元释放出来的高浓度有毒分子）高出 700 倍。制药公司花费了数亿英镑试图开发抑制谷氨酸等毒素的药物。鉴于我们在神经创伤部位发现了这种更有效的神经毒素，它值得紧急关注，并且可能是一个非常有价值的目标。令人惊讶的是，这种神经毒素在神经损伤后基本上仍未被研究。令人兴奋的是，我们已经鉴定出一种多克隆抗体，它可以在体外至少 48 小时内完全阻断该分子杀死中枢神经系统神经元的能力。 目标 1：我们希望开发出抑制这种神经毒素的治疗性“单克隆抗体”。 “单克隆抗体”是一类能够非常有效地抑制特定分子靶点的治疗药物；它们适合针对特定特性（例如尺寸、体内寿命、安全性）进行工程设计，并已在全球范围内提供健康和商业利益。我们现在寻求开发和评估新型单克隆抗体，以提高在培养皿中（目标 1 和 2）或体内（目标 3）暴露于这种神经毒素的人类和啮齿动物 CNS 神经元的存活率。目标2：我们还发现，脊髓损伤后48小时内通过腰椎穿刺获得的脑脊液对培养皿中培养的啮齿动物CNS神经元具有毒性；我们现在希望通过应用我们的新治疗抗体，不使用或结合其他毒素（例如谷氨酸和活性氧）抑制剂，最大限度地提高培养皿中受损人类神经元的存活率。我们将通过将脑脊液分离成组成部分（例如，基于分子电荷或大小）来分析任何其他残留的有毒分子，以便使用现代生化方法（包括但不限于蛋白质组学）进行识别。目标 3：我们希望测试这样的想法：在医学上可行的时间范围内，通过腰椎穿刺（进入脑脊液）将这些治疗性单克隆抗体注射到小鼠体内，可以改善临床相关的挫伤性脊髓损伤模型的结果。我们预测，用治疗性单克隆抗体进行短期治疗将中和这种神经毒素，提高人类中枢神经系统神经元的存活率，并从长远来看改善感觉运动结果（例如步行）。或者，我们将评估腰部注射这种毒素的已知人类蛋白质抑制剂是否可以改善结果。目标 4：最后，我们希望确定缺乏这种神经毒素的小鼠等效物的小鼠是否在相同的临床相关挫伤性脊髓损伤模型中表现出更好的中枢神经系统细胞存活率和更好的恢复能力。这将使我们能够确认治疗性单克隆抗体的特异性及其作用机制，从而帮助我们优化治疗以获得最大效益。临床重要性：这些实验很重要，因为单克隆抗体可以通过直接腰椎穿刺获得，在受伤后数小时内，减少脊髓损伤后的残疾程度，也可能减少中风或脑外伤后的残疾程度。这些实验将帮助我们将这种潜在的疗法更接近临床试验。