Mooney D J, Mazzoni C L, Breuer C, McNamara K, Hern D, Vacanti J P, Langer R
Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge 02139, USA.
Biomaterials. 1996 Jan;17(2):115-24. doi: 10.1016/0142-9612(96)85756-5.
Polyglycolic acid (PGA) fibre meshes are attractive candidates to transplant cells, but they are incapable of resisting significant compressional forces. To stabilize PGA meshes, atomized solutions of poly(L-lactic acid) (PLLA) and a 50/50 copolymer of poly(D,L-lactic-co-glycolic acid) (PLGA) dissolved in chloroform were sprayed over meshes formed into hollow tubes. The PLLA and PLGA coated the PGA fibres and physically bonded adjacent fibres. The pattern and extent of bonding was controlled by the concentration of polymer in the atomized solution and the total mass of polymer sprayed on the device. The compression resistance of devices increased with the extent of bonding, and PLLA bonded tubes resisted larger compressive forces than PLGA bonded tubes. Tubes bonded with PLLA degraded more slowly than devices bonded with PLGA. Implantation of PLLA bonded tubes into rats revealed that the devices maintained their structure during fibrovascular tissue ingrowth, resulting in the formation of a tubular structure with a central lumen. The potential of these devices to engineer specific tissues was exhibited by the finding that smooth muscle cells and endothelial cells seeded onto devices in vitro formed a tubular tissue with appropriate cell distribution.
聚乙醇酸(PGA)纤维网是移植细胞的理想候选材料,但它们无法抵抗显著的压缩力。为了稳定PGA纤维网,将溶解于氯仿中的聚(L-乳酸)(PLLA)和聚(D,L-乳酸-共-乙醇酸)(PLGA)50/50共聚物的雾化溶液喷洒在制成中空管的纤维网上。PLLA和PLGA包覆了PGA纤维,并使相邻纤维物理结合。结合的模式和程度由雾化溶液中聚合物的浓度以及喷洒在装置上的聚合物总质量控制。装置的抗压性随结合程度增加,且PLLA结合的管比PLGA结合的管能抵抗更大的压缩力。与PLGA结合的装置相比,PLLA结合的管降解更慢。将PLLA结合的管植入大鼠体内显示,在纤维血管组织向内生长过程中,这些装置保持了其结构,从而形成了具有中央管腔的管状结构。体外接种到装置上的平滑肌细胞和内皮细胞形成了具有适当细胞分布的管状组织,这一发现展示了这些装置构建特定组织的潜力。