Ha Mi Yeon, Yang Dae Hyeok, You Su Jung, Kim Hyun Joo, Chun Heung Jae
Department of Biomedicine & Health Sciences, College of Medicine, The Catholic University of Korea, Seoul, 06591, Republic of Korea.
Institute of Cell and Tissue Engineering, College of Medicine, The Catholic University of Korea, Seoul, 06591, Republic of Korea.
NPJ Regen Med. 2023 Jan 6;8(1):2. doi: 10.1038/s41536-022-00274-z.
The collagen-mimetic peptide GFOGER possesses the chondrogenic potential and has been used as a cell adhesion peptide or chondrogenic inducer. Here, we prepared an injectable in situ forming composite hydrogel system comprising methoxy polyethylene glycol-b-polycaprolactone (MPEG-PCL) and GFOGER-conjugated PEG-PCL (GFOGER-PEG-PCL) with various GFOGER concentrations based on our recently patented technology. The conjugation of GFOGER to PEG-PCL was confirmed by H NMR, and the particle size distribution and rheological properties for the sol-gel transition behavior of the samples with respect to the GFOGER content were evaluated systemically. In vitro experiments using rat bone marrow-derived mesenchymal stem cells (BMSCs) revealed that the GFOGER-PEG-PCL hydrogel significantly enhanced expression of integrins (β1, α2, and α11), increased expression of FAK, and induced downstream signaling of ERK and p38. Overexpression of chondrogenic markers suggested that BMSCs have the potential to differentiate into chondrogenic lineages within GFOGER-PEG-PCL samples. In vivo studies using a rat osteochondral defect model revealed that transplanted BMSCs with GFOGER-PEG-PCL survived at the defect with strong chondrogenic expression after 4 weeks. The stem cell-laden GFOGER-PEG-PCL hydrogel produced remarkable osteochondral regeneration at 8 weeks of transplantation, as determined by histological findings and micro-CT analysis. The histomorphological score in the GFOGER-PEG-PCL + BMSCs group was ~1.7-, 2.6-, and 5.3-fold higher than that in the GFOGER-PEG-PCL, MPEG-PCL, and defect groups, respectively. Taken together, these results provide an important platform for further advanced GFOGER-based stem cell research for osteochondral repair.
胶原模拟肽GFOGER具有软骨生成潜力，已被用作细胞粘附肽或软骨生成诱导剂。在此，我们基于我们最近获得专利的技术，制备了一种可注射的原位形成复合水凝胶系统，该系统由甲氧基聚乙二醇-b-聚己内酯（MPEG-PCL）和具有不同GFOGER浓度的GFOGER共轭聚乙二醇-聚己内酯（GFOGER-PEG-PCL）组成。通过1H NMR证实了GFOGER与聚乙二醇-聚己内酯的共轭，并系统地评估了样品在溶胶-凝胶转变行为方面的粒径分布和流变学性质与GFOGER含量的关系。使用大鼠骨髓间充质干细胞（BMSC）进行的体外实验表明，GFOGER-PEG-PCL水凝胶显著增强了整合素（β1、α2和α11）的表达，增加了FAK的表达，并诱导了ERK和p38的下游信号传导。软骨生成标志物的过表达表明，骨髓间充质干细胞有潜力在GFOGER-PEG-PCL样品中分化为软骨生成谱系。使用大鼠骨软骨缺损模型进行的体内研究表明，移植了GFOGER-PEG-PCL的骨髓间充质干细胞在4周后在缺损处存活，并具有强烈的软骨生成表达。通过组织学检查和微型CT分析确定，负载干细胞的GFOGER-PEG-PCL水凝胶在移植8周时产生了显著的骨软骨再生。GFOGER-PEG-PCL +骨髓间充质干细胞组的组织形态学评分分别比GFOGER-PEG-PCL、MPEG-PCL和缺损组高约1.7倍、2.6倍和5.3倍。综上所述，这些结果为进一步开展基于GFOGER的干细胞骨软骨修复研究提供了一个重要平台。
