Iwai Terunobu, Ikeguchi Ryosuke, Aoyama Tomoki, Noguchi Takashi, Yoshimoto Koichi, Sakamoto Daichi, Fujita Kazuaki, Miyazaki Yudai, Akieda Shizuka, Nagamura-Inoue Tokiko, Nagamura Fumitaka, Nakayama Koichi, Matsuda Shuichi
Department of Orthopaedic Surgery, Kyoto University, Kyoto, Japan.
Department of Rehabilitation Medicine, Kyoto University, Kyoto, Japan.
PLoS One. 2024 Dec 23;19(12):e0310711. doi: 10.1371/journal.pone.0310711. eCollection 2024.
Human umbilical cord-derived mesenchymal stromal cells (UC-MSCs), which can be prepared in advance and are presumed to be advantageous for nerve regeneration, have potential as a cell source for Bio 3D conduits. The purpose of this study was to evaluate the nerve regeneration ability of Bio 3D conduits made from UC-MSCs using a rat sciatic nerve defect model.
A Bio 3D conduit was fabricated using a Bio 3D printer by placing UC-MSC spheroids into thin needles according to predesigned 3D data. The conduit was transplanted to bridge the 5-mm gaps of Lewis rat sciatic nerve, and nerve regeneration was evaluated at 8 weeks (Bio 3D group). Transplantation of autologous nerve segments (autograft) and silicone tubes represented the positive and negative control groups, respectively. In a second experiment, immunological reactions were evaluated in Bio 3D, autograft, and allograft groups by histochemical staining of transplanted segments in Brown Norway rats.
The mean angle of attack value in the kinematic analysis was significantly better in the Bio 3D group (‒20.1 ± 0.5°) than in the silicone group (‒33.7 ± 1.5°) 8 weeks after surgery. The average diameters of myelinated axons were significantly larger in the Bio 3D group (3.61 ± 0.15 μm) than in the silicone group (3.07 ± 0.12 μm), and the number of myelinated axons was significantly higher in the Bio 3D group (11,201 ± 980) than in the silicone group (8117 ± 646). Histological findings (hematoxylin and eosin [HE] staining and anti-CD3 fluorescent immunostaining) showed that rejection was suppressed in the Bio 3D group compared to the allograft group. Based on macroscopic findings and histological findings (anti-human mitochondrial fluorescent immunostaining), UC-MSCs in the Bio 3D conduit disappeared gradually from week 1 to week 8.
The Bio 3D conduit prepared from UC-MSCs was superior to the silicone tube and achieved comparable nerve regeneration to the autologous (autograft) group. Rejection was suppressed in the Bio 3D group compared to the allograft group. Although this study used a xenograft model, we speculate that rejection was low due to the characteristics of UC-MSCs. UC-MSCs are a useful cell source for Bio 3D conduits.
人脐带间充质基质细胞（UC-MSCs）可以预先制备，被认为有利于神经再生，具有作为生物3D导管细胞来源的潜力。本研究的目的是使用大鼠坐骨神经缺损模型评估由UC-MSCs制成的生物3D导管的神经再生能力。
根据预先设计的3D数据，将UC-MSC球体放入细针中，使用生物3D打印机制造生物3D导管。将导管移植以桥接Lewis大鼠坐骨神经的5毫米间隙，并在8周时评估神经再生情况（生物3D组）。自体神经段移植（自体移植）和硅胶管分别代表阳性和阴性对照组。在第二个实验中，通过对棕色挪威大鼠移植段的组织化学染色，评估生物3D组、自体移植组和同种异体移植组的免疫反应。
术后8周，生物3D组（-20.1±0.5°）运动学分析中的平均攻角值明显优于硅胶组（-33.7±1.5°）。生物3D组有髓轴突的平均直径（3.61±0.15μm）明显大于硅胶组（3.07±0.12μm），生物3D组有髓轴突的数量（11,201±980）明显高于硅胶组（8117±646）。组织学结果（苏木精和伊红[HE]染色以及抗CD3荧光免疫染色）显示，与同种异体移植组相比，生物3D组的排斥反应受到抑制。基于宏观结果和组织学结果（抗人线粒体荧光免疫染色），生物3D导管中的UC-MSCs从第1周到第8周逐渐消失。
由UC-MSCs制备的生物3D导管优于硅胶管，并且实现了与自体（自体移植）组相当的神经再生。与同种异体移植组相比，生物3D组的排斥反应受到抑制。尽管本研究使用了异种移植模型，但我们推测由于UC-MSCs的特性，排斥反应较低。UC-MSCs是生物3D导管的有用细胞来源。
