Development of Biological Scaffolds for Pediatric Patients having Growth Potential

目的研究基于脱细胞基质的问题工程移植物，以提高现有生物假体的耐久性和生长潜力，降低其免疫原性。洗涤剂通常用于去除细胞，而脱细胞取决于它们从组织表面渗透到组织中，并且在大组织或硬组织中可能无法完全实现。方法在无菌条件下分离心脏瓣膜、主动脉、心肌、骨骼肌和气管的孢素组织。立即进行980 Mpa （10,000 atm）的冷等静压（CIP）处理，然后在4℃下清洗（PowerGraft处理）。然后对它们进行组织学研究、猪内源逆转录病毒（PERV）检测、DNA检测、磷脂检测和生物力学研究。结果经CIP处理10 min，清洗7 d后，气管软骨等组织完全游离。压榨适用于整个组织，在此过程中不使用洗涤剂。处理组织中未检测到PERV。有报道称，超过600mpa的CIP对病毒的灭活效果较好。DNA和磷脂含量分别低于1 μg/ml和0.5 mg/g。胶原蛋白和弹性蛋白纤维在脱细胞组织中保持良好，生物力学性能无明显变化。结论PowerGraft能在短时间内完全清除胞素细胞和PERV。这样可以为组织再生提供更安全的脱细胞组织。

OBJECTIVESTissue engineered grafts based on acellular matrices have been studied to give more durability with growth potential and less immunogenicity to the current bioprostheses. Detergents are commonly used for removal of the cells, whereas the decellularization depends on their permeation in the tissue from its surface and may not be achieved completely in large or hard tissues.METHODSPorcine tissues of the heart valves, aorta, cardiac muscle, skeletal muscle, and trachea were isolated under sterile condition. They were treated immediately by cold isostatic pressing (CIP) of 980 Mpa (10,000 atm) followed by washing at 4℃ (PowerGraft treatment). They were then subjected to histological study, porcine endogeneoua retrovirus (PERV) assay, DNA assay, phospholipids assay, and biomechanical study.RESULTSThe tissues including tracheal cartilage were completely cell free when they were treated by the CIP for 10 min and washing for 7 days. The pressing is applied to the whole of the tissue and no detergents are used in the process. There was no PERV detected from the tissue treated. It has been reported that viruses are mostly inactivated by the CIP more than 600 MPa. The amount of DNA and phospholipids were lower than 1 μg/ml and 0.5 mg/g, respectively. The collagen and elastin fibers were well maintained in the acellular tissue and there were no significant changes in biomechanical properties.CONCLUSIONSPorcine cells and PERV were removed completely in a short period by the PowerGraft treatment. This may have more secure acellular tissues for the tissue regeneration.