i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal.
INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal.
J Tissue Eng Regen Med. 2019 Jan;13(1):36-45. doi: 10.1002/term.2766. Epub 2018 Dec 3.
Human mesenchymal stem cells (MSC) are being explored for cell therapies targeting varied human diseases. For that, cells are being expanded in vitro, many times with fetal bovine serum (FBS) as the main source of growth factors. However, animal-derived components should not be used, to avoid immune rejection from the patient that receives the MSC. To solve this issue, different xeno-free media are being developed, and an industrial-grade human plasma fraction (SCC) is a promising candidate to substitute FBS. Indeed, we have previously shown that MSC expanded in SCC-medium maintain their phenotype and genetic stability. However, a reduction on MSC motility was observed when comparing with MSC motility on FBS-medium. Thus, in this present study, we have tested different factors to improve the motility of MSC in SCC-medium. Time lapse assays and experiments with transwells revealed that supplementation of the xeno-free medium with FGF or PDGF, but not TNF-α or SDF-1, increased MSC motility. Interestingly, FGF and PDGF supplementation also led to alterations on MSC morphology to a shape similar to the one observed when using FBS. The mechanism behind the effect of FGF on MSC motility involved the increased expression of αVβ3 integrin. Furthermore, assays with small molecule inhibitors revealed that the signalling molecule p38 MAPK is important for MSC motility and that MEK/ERK and PI3K/AKT also have a role on FGF-supplemented expanded MSC. Thus, it was found that FGF supplementation can improve the motility of xeno-free-expanded MSC and that the cells motility is regulated by αVβ3 integrin.
人骨髓间充质干细胞（MSC）正在被探索用于针对各种人类疾病的细胞疗法。为此，细胞在体外进行扩增，很多时候使用胎牛血清（FBS）作为生长因子的主要来源。然而，为了避免接受 MSC 的患者产生免疫排斥反应，不应使用动物源性成分。为了解决这个问题，正在开发不同的无动物成分培养基，工业级人血浆级分（SCC）是替代 FBS 的有前途的候选物。事实上，我们之前已经表明，在 SCC 培养基中扩增的 MSC 保持其表型和遗传稳定性。然而，与在 FBS 培养基中相比，观察到 MSC 迁移能力降低。因此，在本研究中，我们测试了不同的因素来提高 SCC 培养基中 MSC 的迁移能力。时差测定法和 Transwell 实验表明，用 FGF 或 PDGF 而非 TNF-α或 SDF-1 补充无动物成分培养基可提高 MSC 迁移能力。有趣的是，FGF 和 PDGF 的补充也导致 MSC 形态发生改变，形状类似于使用 FBS 时观察到的形状。FGF 对 MSC 迁移能力的影响的机制涉及到αVβ3 整合素表达的增加。此外，使用小分子抑制剂的测定法表明，信号分子 p38 MAPK 对 MSC 迁移能力很重要，MEK/ERK 和 PI3K/AKT 也对补充 FGF 的扩增 MSC 发挥作用。因此，发现 FGF 补充可以提高无动物成分扩增 MSC 的迁移能力，并且细胞迁移能力受到αVβ3 整合素的调节。
