Department of Orthopaedics, First Affiliated Hospital, Bengbu Medical College, Bengbu, China.
Anhui Province Key Laboratory of Tissue Transplantation, Bengbu Medical College, Bengbu, China.
J Cell Mol Med. 2021 Jan;25(2):880-891. doi: 10.1111/jcmm.16141. Epub 2020 Dec 2.
A key early sign of degenerative disc disease (DDD) is the loss of nucleus pulposus (NP) cells (NPCs). Accordingly, NPC transplantation is a treatment strategy for intervertebral disc (IVD) degeneration. However, in advanced DDD, due to structural damage of the IVD and scaffold mechanical properties, the transplanted cells are less viable and secrete less extracellular matrix, and thus, are unable to efficiently promote NP regeneration. In this study, we evaluated the encapsulation of NPCs in a photosensitive hydrogel made of collagen hydrolysate gelatin and methacrylate (GelMA) to improve NP regeneration. By adjusting the concentration of GelMA, we prepared hydrogels with different mechanical properties. After examining the mechanical properties, cell compatibility and tissue engineering indices of the GelMA-based hydrogels, we determined the optimal hydrogel concentration of the NPC-encapsulating GelMA hydrogel for NP regeneration as 5%. NPCs effectively combined with GelMA and proliferated. As the concentration of the GelMA hydrogel increased, the survival, proliferation and matrix deposition of the encapsulated NPCs gradually decreased, which is the opposite of NPCs grown on the surface of the hydrogel. The controllability of the GelMA hydrogels suggests that these NPC-encapsulating hydrogels are promising candidates to aid in NP tissue engineering and repairing endogenous NPCs.
退变性椎间盘疾病（DDD）的一个早期关键标志是髓核细胞（NPCs）的丢失。因此，NPC 移植是治疗椎间盘退变的一种策略。然而，在晚期 DDD 中，由于椎间盘的结构损伤和支架的机械性能，移植细胞的活力较低，细胞外基质分泌较少，因此无法有效地促进 NP 再生。在这项研究中，我们评估了将 NPC 包封在由胶原蛋白水解明胶和甲基丙烯酰基（GelMA）制成的光敏感水凝胶中，以改善 NP 再生。通过调整 GelMA 的浓度，我们制备了具有不同机械性能的水凝胶。在研究了基于 GelMA 的水凝胶的机械性能、细胞相容性和组织工程指标后，我们确定了用于 NP 再生的包封 NPC 的 GelMA 水凝胶的最佳水凝胶浓度为 5%。NPC 可有效与 GelMA 结合并增殖。随着 GelMA 水凝胶浓度的增加，包封 NPC 的存活率、增殖率和基质沉积逐渐降低，这与 NPC 在水凝胶表面生长的情况相反。GelMA 水凝胶的可控性表明，这些包封 NPC 的水凝胶是辅助 NP 组织工程和修复内源性 NPC 的有前途的候选物。
