兔组织工程同种异体气管支架三种制备方法的比较

目的:探讨深低温冷冻-酶洗法制备的气管支架在去除抗原性、维持生物力学及保护细胞外基质方面的效果。方法:健康新西兰兔24只随机分为气管未处理作为对照A组,深低温冷冻法处理B组,玻璃化法处理C组,深低温冷冻-酶洗法D组,各组样本数均为6。处理后将各组标本行HE染色后光镜观察,戊二醛固定后电镜扫描,并测量气管最大拉伸力、破裂力和变异率等生物力学性能。结果:组织学观察显示对照A组有大量完整的粘膜上皮细胞;B组和C组可见部分气管粘膜上皮细胞;D组标本未见气管粘膜上皮细胞,且细胞核碎裂。电镜显示A、B、C、D组气管支架可见丰富的细胞基质,未暴露胶原纤维。组间两两比较,气管支架的最大拉伸力、最大破裂力和变异率均无统计学差异。结论:综合组织学、扫面电镜和生物力学分析,应用深低温冷冻-酶洗法制备气管支架D组可以有效地去除抗原,维持生物力学性能,并具有较完整的细胞外基质。

Three Preparation Methods of the Rabbit tissue EngineeringAllogeneic Tracheal Stent

Objective:Although it has been proved that detergent-enzymatic is a proper method to obtain non-immunogenictracheal matrices, it could not maintain allograft tissue engineering prefectly and protect biomechanics extra cellular matrix completely.This study mainly focused on finding out the optimal method to obtaine rabbit histological engineering tracheal matrix.Methods:24 adultrabbits were divided into 4 groups (each n=6), group A were not treated as control group,groupB was treated with the method ofcryopreservation, group C was treated with vitrificational method, group D was treated with the method of cryopreservationdetergent-enzymatic. HE dyes and scanning electron microscopy were used to observe the morphology and ultrastructure of the treatedtracheal matrices. The biomechanical properties including maximum tensile force, rupture force and aberration rate of the treated trachealmatrices were measured.Results:There were a lot of epithelial cells in the tracheas of group A and some epithelial cells in the tracheas ofgroup B and group C. But the tracheas of group D could not be seen complete epithelial cells. Under scanning electron microscopy, therewere abundant extracellular matrix and collagen fiber in group A, B, C and D. Finally, no statistical differences were found in themaximum tensile force, rupture force and aberration rate of all groups.Conclusion:The method of cryopreservationdetergent-enzymatic, by which the antigen can be removed, and extracellular matrix and biomechanical properties can be maintainedeffectively, is a better way to prepare tissue engineering tracheal matrix.