Characterization of Regenerative Phenotype of Unrestricted Somatic Stem Cells (USSC) from Human Umbilical Cord Blood (hUCB) by Functional Secretome Analysis*
Characterization of Regenerative Phenotype of Unrestricted Somatic Stem Cells (USSC) from Human Umbilical Cord Blood (hUCB) by Functional Secretome Analysis*
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DOI：
10.1074/mcp.m115.049312
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发表时间：
2015-07
影响因子：
7
通讯作者：
J. Schira;Heiner Falkenberg;Marion Hendricks;D. Waldera-Lupa;G. Kögler;H. Meyer;H. Müller;K. Stühler
中科院分区：
文献类型：
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作者：
J. Schira;Heiner Falkenberg;Marion Hendricks;D. Waldera-Lupa;G. Kögler;H. Meyer;H. Müller;K. Stühler
干细胞移植是一种有前景的增强脊髓损伤后轴突再生的治疗策略。从人脐带血中分离出的非限制性成体干细胞 (USSC) 是一种有吸引力的干细胞群，符合 GMP 级标准，没有任何伦理问题。研究表明，将 USSC 移植到急性损伤的大鼠脊髓中会导致轴突再生和显着的运动恢复，但缺乏细胞替代。相反，USSC 分泌营养因子，增强体外初级皮质神经元的神经突生长。在这里，我们首次应用功能性分泌组方法表征 USSC 分泌的蛋白质，并在体外使用原代皮质神经元验证候选神经突生长促进因子。通过质谱分析和详尽的生物信息学询问，我们鉴定了代表 USSC 分泌组的 1156 个蛋白质。使用 Gene Ontology，我们揭示了 USSC 分泌蛋白组包含参与神经再生的许多相关生物过程的蛋白质，例如细胞粘附、细胞运动、血管形成、细胞骨架组织和细胞外基质组织。例如，我们发现 31 种众所周知的神经突生长促进因子，例如神经元生长调节剂 1、NDNF、SPARC 和 PEDF 涵盖 USSC 分泌组的整个丰度范围。通过原代皮质神经元体外测定，我们验证了 SPARC 和 PEDF 显着参与 USSC 介导的神经突生长，从而强调了它们在改善移植后运动恢复中的作用。根据我们的数据，我们确信 USSC 是再生医学中的一个有价值的工具，因为 USSC 的分泌蛋白组包含一个全面的营养因子网络，不仅通过单一过程支持神经再生，而且通过多种相关的生物过程维持其再生表型。
Stem cell transplantation is a promising therapeutic strategy to enhance axonal regeneration after spinal cord injury. Unrestricted somatic stem cells (USSC) isolated from human umbilical cord blood is an attractive stem cell population available at GMP grade without any ethical concerns. It has been shown that USSC transplantation into acute injured rat spinal cords leads to axonal regrowth and significant locomotor recovery, yet lacking cell replacement. Instead, USSC secrete trophic factors enhancing neurite growth of primary cortical neurons in vitro. Here, we applied a functional secretome approach characterizing proteins secreted by USSC for the first time and validated candidate neurite growth promoting factors using primary cortical neurons in vitro. By mass spectrometric analysis and exhaustive bioinformatic interrogation we identified 1156 proteins representing the secretome of USSC. Using Gene Ontology we revealed that USSC secretome contains proteins involved in a number of relevant biological processes of nerve regeneration such as cell adhesion, cell motion, blood vessel formation, cytoskeleton organization and extracellular matrix organization. We found for instance that 31 well-known neurite growth promoting factors like, e.g. neuronal growth regulator 1, NDNF, SPARC, and PEDF span the whole abundance range of USSC secretome. By the means of primary cortical neurons in vitro assays we verified SPARC and PEDF as significantly involved in USSC mediated neurite growth and therewith underline their role in improved locomotor recovery after transplantation. From our data we are convinced that USSC are a valuable tool in regenerative medicine as USSC's secretome contains a comprehensive network of trophic factors supporting nerve regeneration not only by a single process but also maintained its regenerative phenotype by a multitude of relevant biological processes.