Ramos-Rodriguez David H, Fok Shierly W, Dorais Connor J, Filler Andrea C, Caserta Mason, Leach J Kent
Department of Orthopaedic Surgery, UC Davis Health, Sacramento, California, USA.
Department of Biomedical Engineering, University of California Davis, Davis, California, USA.
Tissue Eng Part A. 2025 Feb;31(3-4):139-151. doi: 10.1089/ten.tea.2024.0267. Epub 2024 Nov 18.
Cartilage regeneration is hindered due to the low proliferative capacity of chondrocytes and the avascular nature of cartilaginous tissue. Mesenchymal stromal cells (MSCs) are widely studied for cartilage tissue engineering, and the aggregation of MSCs into high-density cell spheroids facilitates chondrogenic differentiation due to increased cell-cell contact. Despite the promise of MSCs, the field would benefit from improved strategies to regulate the chondrogenic potential of MSCs differentiated from induced pluripotent stem cells (iPSCs), which are advantageous for their capacity to yield large numbers of required cells. We previously demonstrated the ability of MSC-secreted extracellular matrix (ECM) to promote MSC chondrogenic differentiation, but the combinatorial effect of iPSC-derived MSC (iMSC) spheroids, iMSC-derived decellularized ECM (idECM), and other stimuli (e.g., oxygen tension and transforming growth factor [TGF]-β) on chondrogenic potential has not been described. Similar to MSCs, iMSCs secreted a collagen-rich ECM. When incorporated into spheroids, idECM increased spheroid diameter and promoted chondrogenic differentiation. The combination of idECM loading, chondrogenic media, and hypoxia enhanced glycosaminoglycan (GAG) content 1.6-fold (40.9 ± 4.6 ng vs. 25.6 ± 3.3 ng, < 0.05) in iMSC spheroids. Compared with active TGF-β1, the presentation of latent TGF-β1 resulted in greater GAG content (26.6 ± 1.8 ng vs. 41.9 ± 4.3 ng, < 0.01). Finally, we demonstrated the capacity of individual spheroids to self-assemble into larger constructs and undergo both chondrogenic and hypertrophic differentiation when maintained in lineage-inducing media. These results highlight the potential of idECM to enhance the efficacy of chondrogenic stimuli for improved cartilage regeneration using human MSCs and iMSCs.
由于软骨细胞的低增殖能力和软骨组织的无血管特性,软骨再生受到阻碍。间充质基质细胞(MSCs)在软骨组织工程中得到了广泛研究,MSCs聚集形成高密度细胞球状体可因细胞间接触增加而促进软骨形成分化。尽管MSCs前景广阔,但该领域将受益于改进的策略,以调节从诱导多能干细胞(iPSCs)分化而来的MSCs的软骨形成潜能,iPSCs因其能够产生大量所需细胞而具有优势。我们之前证明了MSCs分泌的细胞外基质(ECM)促进MSCs软骨形成分化的能力,但iPSC来源的MSCs(iMSCs)球状体、iMSCs来源的脱细胞ECM(idECM)和其他刺激因素(如氧张力和转化生长因子[TGF]-β)对软骨形成潜能的联合作用尚未见报道。与MSCs相似,iMSCs分泌富含胶原蛋白的ECM。当整合到球状体中时,idECM增加了球状体直径并促进了软骨形成分化。idECM负载、软骨形成培养基和低氧的组合使iMSC球状体中的糖胺聚糖(GAG)含量提高了1.6倍(40.9±4.6 ng对25.6±3.3 ng,<0.05)。与活性TGF-β1相比,潜伏性TGF-β1的呈现导致更高的GAG含量(26.6±1.8 ng对41.9±4.3 ng,<0.01)。最后,我们证明了单个球状体在谱系诱导培养基中培养时能够自组装成更大的构建体并经历软骨形成和肥大分化。这些结果突出了idECM在增强软骨形成刺激效力以利用人MSCs和iMSCs改善软骨再生方面的潜力。