Department of Orthopaedics, Physical Medicine and Rehabilitation, University Hospital of Munich, 81377, Munich, Germany.
BioMed Center Innovation gGmbh, 95448, Bayreuth, Germany.
BMC Biotechnol. 2020 Aug 27;20(1):48. doi: 10.1186/s12896-020-00641-y.
Human TGF-β has been used in many studies to induce genes coding for typical cartilage matrix components and accelerate chondrogenic differentiation, making it the standard constituent in most cultivation media used for the assessment of chondrogenesis associated with various stem cell types on carrier matrices. However, in vivo data suggests that TGF-β and its other isoforms also induce endochondral and intramembranous osteogenesis in non-primate species to other mammals. Based on previously demonstrated improved articular cartilage induction by a using hTGF-β and hBMP-6 together on hADSC cultures and the interaction of TGF- β with matrix in vivo, the present study investigates the interaction of a chitosan scaffold as polyanionic polysaccharide with both growth factors. The study analyzes the difference between chondrogenic differentiation that leads to stable hyaline cartilage and the endochondral ossification route that ends in hypertrophy by extending the usual panel of investigated gene expression and stringent employment of quantitative PCR.
By assessing the viability, proliferation, matrix formation and gene expression patterns it is shown that hTGF-β + hBMP-6 promotes improved hyaline articular cartilage formation in a chitosan scaffold in which ACAN with Col2A1 and not Col1A1 nor Col10A1 where highly expressed both at a transcriptional and translational level. Inversely, hTGF-β alone tended towards endochondral bone formation showing according protein and gene expression patterns.
These findings demonstrate that clinical therapies should consider using hTGF-β + hBMP-6 in articular cartilage regeneration therapies as the synergistic interaction of these morphogens seems to ensure and maintain proper hyaline articular cartilage matrix formation counteracting degeneration to fibrous tissue or ossification. These effects are produced by interaction of the growth factors with the polysaccharide matrix.
人类 TGF-β 已被用于许多研究中，以诱导编码典型软骨基质成分的基因，并加速软骨形成分化，使其成为评估各种干细胞类型在载体基质上与软骨形成相关的最常用培养介质的标准成分。然而，体内数据表明，TGF-β 及其其他同工型也会诱导非灵长类物种的软骨内和膜内成骨，以及其他哺乳动物。基于先前证明的在 hADSC 培养物上同时使用 hTGF-β 和 hBMP-6 可提高关节软骨诱导的作用，以及 TGF-β 与体内基质的相互作用，本研究探讨了壳聚糖支架作为聚阴离子多糖与这两种生长因子的相互作用。该研究分析了导致稳定透明软骨的软骨形成分化与最终发生肥大的软骨内骨化途径之间的差异，方法是扩展研究基因表达的常用面板，并严格使用定量 PCR。
通过评估细胞活力、增殖、基质形成和基因表达模式，表明 hTGF-β+hBMP-6 可促进壳聚糖支架中透明关节软骨的形成，其中 ACAN 与 Col2A1 而不是 Col1A1 或 Col10A1 的高表达均在转录和翻译水平上。相反，hTGF-β 单独倾向于软骨内骨形成，表现出相应的蛋白和基因表达模式。
这些发现表明，临床治疗方法应考虑在关节软骨再生治疗中使用 hTGF-β+hBMP-6，因为这些形态发生素的协同相互作用似乎可以确保和维持适当的透明关节软骨基质形成，防止向纤维组织或骨化退化。这些作用是通过生长因子与多糖基质的相互作用产生的。
