Orthopaedic Surgery, Osaka University Graduate School of Medicine, Suita, Japan.
Sensory and Motor System Medicine, The University of Tokyo, Tokyo, Japan.
J Tissue Eng Regen Med. 2019 Mar;13(3):446-458. doi: 10.1002/term.2795. Epub 2019 Feb 20.
As an alternative to chondrocytes-based cartilage repair, stem cell-based therapies have been investigated. Specifically, human synovium-derived stem cells (hSSCs) are a promising cell source based on their highly capacities for chondrogenesis, but some methodological improvements are still required towards optimal cartilage regeneration. Recently, a small compound, TD-198946, was reported to promote chondrogenesis of several stem cells, but the effect on hSSCs is still unknown. This study aimed to examine the effects of TD-198946 on chondrocyte differentiation and cartilaginous tissue formation with hSSCs. A range of concentrations of TD-198946 were examined in chondrogenic cultures of hSSC-derived cell pellets. The effect of TD-198946 on glycosaminoglycan (GAG) production, chondrocyte marker expression, and cartilaginous tissue formation was assessed. At concentrations >1 nM, TD-198946 dose-dependently enhanced GAG production, particularly hyaluronan, whereas chondrocyte differentiation was not impacted. When combined with transforming growth factor β3 (TGFβ3), TD-198946 promoted chondrocyte differentiation and production of cartilaginous matrices at doses <1 nM as judged by SOX9, S100, and type 2 collagen upregulation. Conversely, doses >1 nM TD-198946 attenuated TGFβ3-associated chondrocyte differentiation, but aggrecan was efficiently produced at 1 to 10 nM TD-198946 as judged by safranin O staining. Thus, TD-198946 exhibited different dose ranges for either GAG synthesis or chondrocyte differentiation. Regarding use of TD-198946 for in vitro engineering of cartilage, cartilaginous particles rich in type 2 collagen and GAG were predominately created with TGFβ3 + 0.25 nM TD-198946. These studies have demonstrated that TD-198946 synergistically enhances chondrogenesis of hSSCs in a unique dose range, and such findings may provide a novel strategy for stem cell-based cartilage therapy.
作为软骨修复的替代方法，人们研究了基于干细胞的治疗方法。具体而言，人滑膜衍生干细胞（hSSC）是一种有前途的细胞来源，因为其具有很高的软骨生成能力，但为了实现最佳的软骨再生，仍需要一些方法学上的改进。最近，一种小分子化合物 TD-198946 被报道能促进几种干细胞的软骨生成，但它对 hSSC 的作用仍不清楚。本研究旨在探讨 TD-198946 对 hSSC 来源细胞球软骨分化和软骨组织形成的影响。研究人员在 hSSC 来源的细胞球软骨生成培养物中检查了一系列 TD-198946 浓度。评估了 TD-198946 对糖胺聚糖（GAG）产生、软骨细胞标志物表达和软骨组织形成的影响。在浓度>1 nM 时，TD-198946 呈剂量依赖性地增强 GAG 产生，特别是透明质酸，而对软骨细胞分化没有影响。当与转化生长因子β3（TGFβ3）联合使用时，TD-198946 在<1 nM 剂量下促进软骨细胞分化和软骨基质的产生，这可以通过 Sox9、S100 和 II 型胶原的上调来判断。相反，在浓度>1 nM TD-198946 时，TD-198946 减弱了 TGFβ3 相关的软骨细胞分化，但在 1 至 10 nM TD-198946 时，聚集蛋白聚糖有效地产生，这可以通过番红 O 染色来判断。因此，TD-198946 在 GAG 合成或软骨细胞分化方面表现出不同的剂量范围。关于 TD-198946 用于软骨体外工程，富含 II 型胶原和 GAG 的软骨颗粒主要是在用 TGFβ3+0.25 nM TD-198946 时产生的。这些研究表明，TD-198946 在独特的剂量范围内协同增强 hSSC 的软骨生成，这些发现可能为基于干细胞的软骨治疗提供一种新策略。
