Guo Jason L, Diaz-Gomez Luis, Xie Virginia Y, Bittner Sean M, Jiang Emily Y, Wang Bonnie, Mikos Antonios G
Department of Bioengineering, Rice University, Houston, TX.
Bioprinting. 2021 Jun;22. doi: 10.1016/j.bprint.2021.e00136. Epub 2021 Mar 26.
Osteochondral repair remains a significant clinical challenge due to the multiple tissue phenotypes and complex biochemical milieu in the osteochondral unit. To repair osteochondral defects, it is necessary to mimic the gradation between bone and cartilage, which requires spatial patterning of multiple tissue-specific cues. To address this need, we have developed a facile system for the conjugation and patterning of tissue-specific peptides by melt extrusion of peptide-functionalized poly(ε-caprolactone) (PCL). In this study, alkyne-terminated PCL was conjugated to tissue-specific peptides via a mild, aqueous, and Ru(II)-catalyzed click reaction. The PCL-peptide composites were then 3D printed by multimaterial segmented printing to generate user-defined patterning of tissue-specific peptides. To confirm the bioactivity of 3D printed PCL-peptide composites, bone- and cartilage-specific scaffolds were seeded with mesenchymal stem cells and assessed for deposition of tissue-specific extracellular matrix . PCL-peptide scaffolds successfully promoted osteogenic and chondrogenic matrix deposition, with effects dependent on the identity of conjugated peptide.
由于骨软骨单元中存在多种组织表型和复杂的生化环境，骨软骨修复仍然是一项重大的临床挑战。为了修复骨软骨缺损，有必要模拟骨与软骨之间的渐变，这需要对多种组织特异性信号进行空间图案化。为满足这一需求，我们开发了一种简便的系统，通过肽功能化聚己内酯（PCL）的熔融挤出实现组织特异性肽的共轭和图案化。在本研究中，炔基封端的PCL通过温和的水相Ru（II）催化点击反应与组织特异性肽共轭。然后通过多材料分段打印对PCL-肽复合材料进行3D打印，以生成用户定义的组织特异性肽图案。为了确认3D打印的PCL-肽复合材料的生物活性，将骨和软骨特异性支架接种间充质干细胞，并评估组织特异性细胞外基质的沉积情况。PCL-肽支架成功促进了成骨和软骨基质沉积，其效果取决于共轭肽的特性。
