应用组织工程材料栓塞动脉瘤的初步研究

Embolization of aneurysm by roblast tissue hydrogel, a tissue engineering material： experiment with rabbits

目的探讨壳聚糖-甘油磷酸钠-成纤维细胞水凝胶作为颅内动脉瘤栓塞材料的可行性。方法配制2％（w／v）壳聚糖与56％（w／v）甘油磷酸钠溶液，不同比例混合，测定混合液pH、37℃成胶时间及力学强度，体外观察兔皮肤成纤维细胞在不同配比壳聚糖-甘油磷酸钠水凝胶中生长状态，选择最佳比例。将Brdu标记的成纤维细胞与壳聚糖-甘油磷酸钠水凝胶混合栓塞兔颈动脉，评价组织相容性。最终栓塞兔动脉瘤模型。结果当壳聚糖／甘油磷酸钠在7：1时，pH值为7．28，成胶时间为（260±18）s，力学强度可达14kPa，细胞生存率最高，达（89．0±2．7）％。颈动脉栓塞，透视下可见混合物显影良好，局部组织切片显示（HE染色）：1周时凝胶中散在较多细胞及钽粉，凝胶与血管壁边界较清，内皮细胞完整。4周时凝胶与血管壁边界不清，可见周边凝胶被细胞成分包绕降解。免疫荧光显示，4周标本中可见较多标记的成纤维细胞。兔动脉瘤栓塞术中见动脉瘤不显影，术后3d病理见动脉瘤被凝胶栓塞，内膜细胞形态正常，动脉壁内未见明显炎性细胞浸润。结论短期观察，壳聚糖-甘油磷酸钠-成纤维细胞水凝胶可用于动脉瘤栓塞。

Objective To evaluate the feasibility of the injectable thermosetting chitosan - glycerophosphate-fibroblast （ C-GP-FB ） hydrogel as an embolizing material of intracranial aneurysm. Methods 2% chitosan solution and 56% glyeerophosphate solution were mixed in different volume ratio to detect the pH, colloidization time at 37 ℃, and mechanic strength. Fibroblasts were isolated from the skin of a rabbit and cultured with C-GP hydrogel of different, ratios so as to determine the best ratio. Six rabbits underwent construction of aneurysm in the right branehioeephalie trunk. Three weeks later C- GP-FB hydrogel was infused into the aneurysm via microtube and balloon. X-ray photography was conducted soon to observe the embolizing effect. Three days, 1 week, and 4 weeks later tea rabbits were killed respectively with their aneurysms taken out to undergo HE staining and microscopy. Result When the ratio of C/GP was 7：1 at pH 7. 28, the eolloidization time was （260 ± 18） see, and the mechanic strength reached 14 kPa. The C/GP volume ratio of 7：1 was regarded as the best ratio. When the fibroblasts were cultured with the C-GP hydrogel with the C/GP volume ratio of 7：1 the survival rate of the fibroblasts reached the peak of （ 89 ± 2. 74） %. X-ray photography showed that image of aneurysm failed to be spotted immediately after the infusion of the C-GP hydrogel. HE staining and microscopy showed that C-GP-FB gel had fine visualization under X-ray. Histological section（ HE stain） showed that 3 days after the infusion the aneurysms was embolized by the C-GP-FB hydrogel and no obvious inflammatory cell was seen in the arterial wall; the first week there were many cells in the gel, the boundary between the C-GP-FB gel and vessel wall was clear, and the endothelioeytes were complete; and in the fourth week, the boundary between the gel and vessel wall was obscure, slight degradation could be observed in the edge of hydrogel, and showed that there were many labeled cell in the gel . Conclusion In the short term view, C-GP-FB hydrogel can be used to embolize aneurysms, at least with an obvious short-term effect.