Ellis Marianne J, Chaudhuri Julian B
Centre for Regenerative Medicine, Department of Chemical Engineering, University of Bath, Claverton Down, Bath, UK.
Biotechnol Bioeng. 2007 Jan 1;96(1):177-87. doi: 10.1002/bit.21093.
Mass transfer limitations of scaffolds are currently hindering the development of 3-dimensional, clinically viable, tissue engineered constructs. We have developed a poly(lactide-co-glycolide) (PLGA) hollow fibre membrane scaffold that will provide support for cell culture, allow psuedovascularisation in vitro and provide channels for angiogenesis in vivo. We produced P(DL)LGA flat sheet membranes using 1, 4-dioxane and 1-methyl-2-pyrrolidinone (NMP) as solvents and water as the nonsolvent, and hollow fibre membranes, using NMP and water, by dry/wet- and wet-spinning. The resulting fibres had an outer diameter of 700 micro m and an inner diameter of 250 micro m with 0.2-1.0 micro m pores on the culture surface. It was shown that varying the air gap and temperature when spinning changed the morphology of the fibres. The introduction of a 50 mm air gap caused a dense skin of 5 micro m thick to form, compared to a skin of 0.5 micro m thick without an air gap. Spinning at 40 degrees C produced fibres with a more open central section in the wall that contained more, larger macrovoids compared to fibres spun at 20 degrees C. Culture of the immortalised osteogenic cell line 560pZIPv.neo (pZIP) was carried out on the P(DL)LGA flat sheets in static culture and in a P(DL)LGA hollow fibre bioreactor under counter-current flow conditions. Attachment and proliferation was statistically similar to tissue culture polystyrene on the flat sheets and was also successful in the hollow fibre bioreactor. The P(DL)LGA hollow fibres are a promising scaffold to address the size limitations currently seen in tissue engineered constructs.
支架的传质限制目前阻碍了三维、临床可行的组织工程构建体的发展。我们开发了一种聚(丙交酯-共-乙交酯)(PLGA)中空纤维膜支架,该支架将为细胞培养提供支持,允许体外假血管形成,并为体内血管生成提供通道。我们使用1,4-二氧六环和1-甲基-2-吡咯烷酮(NMP)作为溶剂,水作为非溶剂制备了P(DL)LGA平板膜,并通过干/湿纺丝和湿纺丝使用NMP和水制备了中空纤维膜。所得纤维的外径为700微米,内径为250微米,在培养表面具有0.2-1.0微米的孔隙。结果表明,纺丝时改变气隙和温度会改变纤维的形态。引入50毫米的气隙会导致形成5微米厚的致密皮层,而没有气隙时皮层厚度为0.5微米。与在20℃下纺制的纤维相比,在40℃下纺制的纤维在壁上的中央部分更开放,包含更多、更大的大孔隙。在静态培养条件下,将永生化成骨细胞系560pZIPv.neo(pZIP)培养在P(DL)LGA平板上,并在逆流条件下培养在P(DL)LGA中空纤维生物反应器中。附着和增殖在统计学上与平板上的组织培养聚苯乙烯相似,并且在中空纤维生物反应器中也成功。P(DL)LGA中空纤维是一种有前途的支架,可解决目前组织工程构建体中存在的尺寸限制问题。