The development of efficacious bone substitute biomaterials remains a major challenge for research and clinical surgical. Herein, we constructed triple helix recombinant collagen (THRC) -based hydrogels loading bone morphogenetic protein-2 (BMP-2) to stimulate bone regeneration in cranial defects. A series of in situ forming hydrogels, denoted as THRC-oxidized carboxymethylcellulose (OCMC)-N-succinyl-chitosan (NSC) hydrogels, was synthesized via a Schiff base reaction involving OCMC, THRC and NSC. The hydrogels underwent rapid formation under physiological pH and temperature conditions. The composite hydrogel exhibits a network structure characterized by uniform pores, the dimensions of which can be tuned by varying THRC concentrations. The THRC-OCMC-NSC and THRC-OCMC-NSC-BMP2 hydrogels display heightened mechanical strength, substantial biodegradability, and lower swelling properties. The THRC-OCMC-NSC hydrogels show exceptional biocompatibility and bioactivity, accelerating cell proliferation, adhesion, and differentiation. Magnetic resonance imaging, computed tomography and histological analysis of rat cranial defects models revealed that the THRC-OCMC-NSC-BMP2 hydrogels substantially promote new bone formation and expedite bone regeneration. The novel THRC-OCMC-NSC-BMP2 hydrogels emerge as promising candidates for bone substitutes, demonstrating substantial potential in bone repair and regeneration applications.

中文翻译：

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负载骨形态发生蛋白2的三螺旋重组胶原基水凝胶可增强骨缺损愈合

有效骨替代生物材料的开发仍然是研究和临床外科的主要挑战。在此，我们构建了基于三螺旋重组胶原 (THRC) 的水凝胶，负载骨形态发生蛋白 2 (BMP-2)，以刺激颅骨缺损的骨再生。通过涉及 OCMC、THRC 和 NSC 的席夫碱反应合成了一系列原位形成水凝胶，称为 THRC 氧化羧甲基纤维素 (OCMC)-N-琥珀酰壳聚糖 (NSC) 水凝胶。水凝胶在生理pH和温度条件下快速形成。该复合水凝胶呈现出以均匀孔为特征的网络结构，其尺寸可以通过改变 THRC 浓度来调节。 THRC-OCMC-NSC 和 THRC-OCMC-NSC-BMP2 水凝胶表现出更高的机械强度、显着的生物降解性和更低的膨胀特性。 THRC-OCMC-NSC 水凝胶表现出卓越的生物相容性和生物活性，可加速细胞增殖、粘附和分化。大鼠颅骨缺损模型的磁共振成像、计算机断层扫描和组织学分析表明，THRC-OCMC-NSC-BMP2 水凝胶可显着促进新骨形成并加速骨再生。新型 THRC-OCMC-NSC-BMP2 水凝胶成为骨替代品的有前途的候选者，在骨修复和再生应用中表现出巨大的潜力。