血管内皮生长因子混合Ⅰ型胶原修饰β-磷酸三钙多孔支架的血管化

Vascularization of vascular endothelial growth factor and collagen I modified beta-tricalcium phosphate porous scaffolds

背景:目前听骨链重建仍是治疗传导性聋的重要方法,多种生物材料被应用于听骨链重建,但都忽略了听骨植入后的血液供应,更未形成真正意义的骨组织。目的:观察经血管内皮生长因子混合Ⅰ型胶原修饰β-磷酸三钙多孔支架植入豚鼠听泡内的血管化效果。方法:取豚鼠60只制作听泡内壁黏膜缺损创面,随机分组,实验组听泡内植入经血管内皮生长因子混合Ⅰ型胶原修饰的β-磷酸三钙多孔支架,对照组植入Ⅰ型胶原修饰的β-磷酸三钙多孔支架,空白对照组植入β-磷酸三钙多孔支架,植入后1,2,3,4周扫描电镜观察支架表面情况,苏木精-伊红及免疫组织化学染色观察支架内血管生成情况,甲苯胺蓝染色观察支架内新骨生成。结果与结论:实验组植入1周后内皮细胞大量生长,血管管腔形成,3周时达血管生长高峰并可见微孔间交通支形成;另两组2周时可见血管管腔形成,但无微孔间交通支形成,且实验组各时间段血管计数均高于对照组和空白对照组(P<0.05)。3组支架表面及微孔内细胞黏附生长,形态基本一致。植入4周时实验组支架内成骨较其他两组明显。表明经血管内皮生长因子混合Ⅰ型胶原修饰的β-磷酸三钙多孔支架在豚鼠中耳环境中能够有效实现血管化,促进支架内新骨形成。

BACKGROUND：The auditory ossicle chain reconstruction is stil an important method to treat conductive deafness. Although a great variety of materials have been applied, the blood supply of otosteon after the implantation is ignored. Moreover, there is no real bone formed. OBJECTIVE：To observe the angiogenesis of vascular endothelial growth factor and col agen I modifiedβ-tricalcium phosphate porous scaffold which is implanted into the otocyst of guinea pig. METHODS：Total y 60 guinea pigs were randomly divided into experimental group （vascular endothelial growth factor and col agen I modifiedβ-tricalcium phosphate porous scaffold）, col agen I control group （col agen I modifiedβ-tricalcium phosphate porous scaffold） and blank control group （β-tricalcium phosphate porous scaffold）. The guinea pigs were executed under anesthesia at weeks 1, 2, 3, 4 respectively. The surface of scaffolds was observed by scanning electron microscopy. The angiogenesis of scaffolds were observed by hematoxylin-eosin staining and CD34 immunohistochemistry staining, and then the microvascular density was counted. The osteogenesis of the scaffolds was observed by toluidine blue staining. RESULTS AND CONCLUSION：Endothelial cel proliferation and lumen formation could be observed after 1 week in the experimental group, and the angiogenesis reach the peak after 3 weeks with traffic branches formedbetween micropores. In the other two groups, the lumen formed at 2 weeks but no traffic branches were＆amp;nbsp;visible. The sprouting of new blood vessels in the pores were observed more in the experimental group than the other two groups （P＜0.05）. The adherence and proliferation of cel s could be examined in the surface and pores of the scaffold by scanning electron microscope. After 4 weeks, the osteogenesis could be observed by toluidine blue staining, especial y in the experimental group. These findings suggest that the vascular endothelial growth factor and col agen I modifiedβ-tricalcium phosphate porous scaffold can realize an effective vascularization in the environment of guinea pigs’ middle ear. What’s more, the scaffold also can promote bone formation.