The experimental study for creating an artificial nerve conduit with Schwann cells

目的：应用雪旺细胞或骨髓细胞的可吸收人工神经管桥接大鼠坐骨神经缺损区，并探讨其应用价值。方法：实验I：应用大孔胶原管修复15 mm长的神经缺损区(n=12)。实验二：使用聚乳酸管桥接15 mm长的神经缺损区。分别制作聚乳酸(PLA)组(n=6)、层粘连蛋白包被聚乳酸(PLA)组(n=3)、层粘连蛋白包被聚乳酸/骨髓单核细胞组(LMMC)(n=3)。实验三：使用聚乳酸管桥接15 mm长的神经缺损区。结果：实验I：术后8周，大体观察均为管腔连续性，3例管腔中央可见神经再生。多孔结构的消失似乎阻碍了轴突的再生。实验二：术后8周，聚乳酸和层粘连蛋白包裹的聚乳酸中枢神经未见再生。骨髓单核细胞组神经再生中心2例，远端1例。实验三：术后8周，聚乳酸组和骨髓基质细胞组中心未见神经再生。1例培养的雪旺细胞组在中心可见神经再生。结论：我们研制的聚乳酸导管在一定时期内保持了输卵管的构筑，可作为一种神经导管。由于大量培养的雪旺细胞需要牺牲更大的周围神经，所以使用培养的雪旺细胞是困难的。另一种观点认为，骨髓单核细胞促进神经再生。

Purpose : We performed experimental studies of bridging a nerve gap of a rat sciatic nerve by absorbable artificial tubes with Schwann cells or bone marrow cells and investigated the usefulness of them.Methods : Experimet I : We used a macroporous collagen tube and bridged a 15mm long nerve defect (n=12). Experiment II : We used a PLA tube and bridged a 15mm long nerve defect. PLA group (n=6), laminin-coated PLA group (n=3), laminin-coated PLA with bone marrow monocyte cells group(n=3) were made. Experiment III : We used a PLA tube and bridged a 15mm long nerve defect. PLA packed with collagen gel group (n=3), PLA packed with collagen gel with cultured Schwann cells group (n=3), PLA packed with collagen gel with cultured bone marrow stromal cells group (n=3) were made.Results : Experimet I : Eight weeks postoperatively the continuity of a tube was held in all cases macroscopically, but microscopically nerve regeneration was seen at the center of the tube in three cases. Disappearance of porous architecture seemed to prevent axons from regenerating. Experiment II : Eight weeks postoperatively nerve regeneration was not seen at the center in PLA group and laminin-coated PLA group. Nerve regeneration was seen at the center in two cases and at the distal part in a case of of bone marrow monocyte cells group. Experiment III : Eight weeks postoperatively nerve regeneration was not seen at the center in PLA group and cultured bone marrow stromal cell group. Nerve regeneration was seen at the center in a case of cultured Schwann cells group.Conclusion : The PLA tube that we invented was considered to be useful as a nerve conduit because of keeping tubal architecture at some periods. As large amount of cultured Schwann cells needs the sacrifice of a larger peripheral nerve, the use of cultured Schwann cells is difficult. Alternatively, it was suggested that bone marrow monocyte cells facilitate nerve regeneration.