Generation of Tissue Engineered Nerve Grafts from GalSafe Porcine Neurons

项目摘要 组织工程医疗产品具有巨大的前景，以解决目前无法弥补的影响， 神经创伤和/或神经变性疾病。Axonova医疗公司的主导产品，组织工程神经 TENG是一种具有生物活性的“活支架”，被证明可以促进神经的快速再生和功能恢复 当植入以修复主要周围神经损伤（PNI）时。将活的神经元细胞作为 生物质，Axonova通常生物制造TENG，由活的，长的，排列的轴突束组成，通过 轴突“伸展生长”的专有过程。迄今为止，TENG已被证明一贯促进宿主 轴突再生和改善功能恢复相比，目前的临床实践中，无论是小的和大的 PNI的动物模型，包括5cm节段性缺损的修复。为了转移到制造业- 符合生物质标准，Axonova与Revivicor合作，利用其基因技术生产GalSafe® TENG。 工程化的猪神经元以减轻最终移植到人体后的宿主免疫反应。 通过第一阶段的努力，GalSafe® TENG成功地拉伸生长，生产出长度为 1 cm、3 cm和5 cm，其健康和轴突密度达到或超过既定质量基准。 此外，将1cm TENG移植到啮齿动物PNI模型中以证明再生功效， 这表明GalSafe® TENG存活下来，并通过专有的 TENG的作用机制，称为轴突促进轴突再生（AFAR）。沿着选择 安全和容易获得的起始生物质，其他产品开发挑战包括生物保护和 质量保证标准，以延长产品的保质期、运输和保持产品的功效。 因此，目前的第二阶段SBIR计划解决了临床级生物制造的一个关键方面， 特别是验证有效的储存方案和放行标准，确保产品健康，无菌， 和力量TENG将由符合cGMP的细胞来源（GalSafe®猪神经元）生物制造， 使用符合cGMP的保存方案储存，然后在PNI的小型和大型动物模型中进行测试 来证明再生功效具体来说，Axonova将系统地完成这一目标， 该计划跨越3个具体目标：（1）确定新鲜GalSafe® TENG在已建立的猪 PNI模型;（2）有效地生物保护GalSafe® TENG，以延长保质期并验证非侵入性释放 标准;和（3）确定生物保存的GalSafe® TENG在啮齿动物体内的效力和功效，以及 猪PNI模型。该计划解决了下一代组织翻译中的一个重大挑战 通过验证活生物制品的制造、储存和放行标准， 产品，使最终在人类身上进行测试。能够将GalSafe® TENG作为一种“离线”存储和分发， 货架”产品将通过降低成本和扩大患者可及性而极大地增加商业潜力， 改善患有主要PNI的衰弱效应的患者的恢复和生活质量。

PROJECT SUMMARY Tissue engineered medical products have tremendous promise to address the currently irreparable effects of neurotrauma and/or neurodegenerative diseases. Axonova Medical’s lead product, the tissue engineered nerve graft (TENG), is a bioactive “living scaffold” proven to promote rapid nerve regeneration and functional restoration when implanted to repair major peripheral nerve injury (PNI). Implementing living neuronal cells as the starting biomass, Axonova routinely biomanufactures TENGs comprised of living, long, aligned axon tracts through the proprietary process of axon “stretch-growth”. To date, TENGs have been shown to consistently promote host axon regeneration and improve functional recovery compared to current clinical practices in both small and large animal models of PNI, including the repair of 5 cm segmental defects. In order to move to a manufacturing- compliant biomass, Axonova has partnered with Revivicor to generate GalSafe® TENGs using their genetically engineered porcine neurons to mitigate a host immune response upon eventual transplantation in humans. Through the Phase I efforts, GalSafe® TENGs were successfully stretch-grown to create products at lengths of 1 cm, 3 cm, and 5 cm with a health and axon density that met or exceeded established quality benchmarks. Moreover, 1 cm TENGs were transplanted into a rodent PNI model to demonstrate regenerative efficacy, revealing that GalSafe® TENGs survived as well as actively drove host axonal regeneration via the proprietary mechanism-of-action of TENGs, referred to as axon facilitated axon regeneration (AFAR). Along with choosing a safe and readily available starting biomass, other product development challenges include biopreservation and quality assurance criteria to allow increased shelf life, transportation, and maintained efficacy of the product. Accordingly, the current Phase II SBIR program addresses a key facet of clinical grade biomanufacturing, specifically the validation of an effective storage protocol and release criteria ensuring product health, sterility, and potency. TENGs will be biofabricated from a cGMP-compliant cell source (GalSafe® porcine neurons), cold- stored using a cGMP-compliant preservation protocol, and then tested in small and large animal models of PNI to demonstrate regenerative efficacy. Specifically, Axonova will systematically complete the objectives of this program across 3 Specific Aims: (1) determine the efficacy of fresh GalSafe® TENGs in an established porcine PNI model; (2) effectively biopreserve GalSafe® TENGs to increase shelf-life and validate non-invasive release criteria; and (3) determine the potency and efficacy of biopreserved GalSafe® TENGs in vivo in rodent and porcine PNI models. This program addresses a major challenge in the translation of next-generation tissue engineered medical products by validating manufacturing, storage and release criteria for a living biological product to enable eventual testing in humans. The ability to store and distribute GalSafe® TENGs as an “off-the- shelf” product will vastly increase commercial potential by reducing costs and expanding patient access, thereby improving recovery and quality of life for patients suffering from the debilitating effects of major PNI.