Platform for practical delivery of oral autoantigens as co-therapies for neurological disease

摘要 创建有效的口服自身抗原疗法的困难基本上是双重的：实用性和 功效实际上，大多数蛋白质自身抗原的制造、给药将是昂贵的，并且可能不 在通过胃肠道后保持完整。从治疗上讲，即使一些蛋白质 自身抗原存活下来，与肠道相关类淋巴组织（GALT）中的免疫细胞相互作用， 显著降低患者自身免疫性T和B细胞应答的作用尚未得到有效证实。 开发一个常规的，实用的口服自身抗原治疗策略肯定是一个困难和风险的命题。 证明常规和实用的口服自身抗原治疗技术的可行性将是 独特.作为原理的证明，我们表达了一种自身抗原（人烟碱受体的α 1亚基）， 乙酰胆碱受体）与呼肠孤病毒σ 1蛋白融合。逻辑 这种方法的背后在于呼肠孤病毒sigma 1蛋白（sigma 1）结合微折叠细胞的能力 覆盖粘膜淋巴组织。与σ 1融合的自身抗原将免疫原靶向这些细胞， 在“耐受环境”中递送自身抗原以限制正在进行的自身免疫应答。此外，虽然这种 自身抗原和融合蛋白难以制造，表达大量自身抗原和融合蛋白的能力也很困难。 相当大蛋白质，并将其作为可消耗的豆奶制剂给药，这是该平台表达所独有的 系统我们将在这些研究中关注的自身抗原是大多数肌无力患者 严重者对烟碱乙酰胆碱受体的细胞外部分产生免疫应答 α 1链（AChR）。 在这个提议中，我们将生产大量的AChR-sigma 1浓缩物， 表达该融合蛋白的大豆种子。研究以确定该药物的生产和封装 将进行粉末材料。我们还将使用大鼠模型来开始定义体内安全性 分布和使用实验性自身免疫性重症肌无力模型的治疗功效。 这些研究的完成将解决一些最重要的监管障碍， 含有这种新型融合蛋白的大豆基浓缩物。如果成功，疗效研究将 提示我们已经为自身免疫性疾病肌无力开发了一种候选的口服耐受疗法 重症（MG）。大豆衍生疗法的实际优势，结合 在耐受性环境中将自身抗原递送至肠道免疫系统，代表了一种新的解决方案， 重症肌无力和潜在的许多其他自身免疫性疾病的治疗干预。

ABSTRACT The difficulties for creating an efficacious oral autoantigen therapy are basically twofold: practicality and efficacy. Practically, most protein autoantigens will be expensive to manufacture, to administer, and may not remain intact following passage through the gastrointestinal tract. Therapeutically, even if some of the protein autoantigens survive to interact with immune cells in the Gut Associated Lymphoid Tissue (GALT), their ability to significantly reduce autoimmune T and B cells responses in patients has not been effectively demonstrated. Developing a routine, practical strategy for oral autoantigen therapy is certainly a difficult and risky proposition. Demonstrating the feasibility of a technology for routine and practical oral autoantigen therapy would be unique. As a proof of principle, we have expressed an autoantigen (the alpha 1 subunit of the human nicotinic acetylcholine receptor) as a fusion with the reovirus sigma1 protein in transgenic soybean seeds. The logic behind such an approach lies in the ability of the reovirus sigma1 protein (sigma1) to bind microfold cells covering mucosal lymphoid tissues. Autoantigens fused to sigma1 target the immunogen to these cells, and deliver the autoantigen in a “tolerizing context” to limit an ongoing autoimmune response. Further, while such autoantigens and fusion proteins are difficult to manufacture, the ability to express large quantities of a sizeable protein, and administer it as a consumable soymilk formulation is unique to this platform expression system. The autoantigen that we will focus on for these studies is one that most patients with myasthenia gravis mount an immune response against: i.e. the extracelluar portion of the nicotinic acetylcholine receptor alpha 1 chain (AChR). In this proposal, we will manufacture quantities of an AChR-sigma1 concentrate made from transgenic soybean seeds expressing this fusion protein. Studies to define manufacturing and encapsulation of this powdered material will be conducted. We will also use a rat model to begin to define safety, in vivo distribution, and therapeutic efficacy using a model of experimental autoimmune myasthenia gravis. Completion of these studies will address some of the most important regulatory hurdles for approval of oral soy-based concentrates containing this novel fusion protein. If successful, the therapeutic efficacy studies will suggest that we have developed a candidate oral tolerance therapy for the autoimmune disease, myasthenia gravis (MG). The practical advantages of soybean-derived therapeutics, combined with the efficacy of delivering an autoantigen in a tolerizing context to the gut immune system, represent a novel solution for therapeutic intervention for myasthenia gravis, and potentially many other autoimmune diseases.