Selvam Shivaram, Chang Wenji V, Nakamura Tamako, Samant Deedar M, Thomas Padmaja B, Trousdale Melvin D, Mircheff Austin K, Schechter Joel E, Yiu Samuel C
Mork Family Department of Chemical Engineering and Materials Science, Viterbi School of Engineering, University of Southern California, Los Angeles, California.
Tissue Eng Part C Methods. 2009 Sep;15(3):463-74. doi: 10.1089/ten.tec.2008.0431.
With the eventual goal of developing a tissue-engineered tear secretory system, we found that primary lacrimal gland acinar cells grown on solid poly(L-lactic acid) (PLLA) supports expressed the best histiotypic morphology. However, to be able to perform vectorial transport functions, epithelia must be supported by a permeable substratum. In the present study, we describe the use of a solvent-cast/particulate leaching technique to fabricate microporous PLLA membranes (mpPLLAm) from PLLA/polyethylene glycol blends. Scanning electron microscopy revealed pores on both the air-cured ( approximately 4 microm) and glass-cured sides (<2 microm) of the mpPLLAm. Diffusion studies were performed with mpPLLAm fabricated from 57.1% PLLA/42.9% polyethylene glycol blends to confirm the presence of channelized pores. The data reveal that glucose, L-tryptophan, and dextran (a high molecular weight glucose polymer) readily permeate mpPLLAm. Diffusion of the immunoglobulin G through the mpPLLAm decreased with time, suggesting the possible adsorption and occlusion of the pores. Cells cultured on the mpPLLAm (57.1/42.9 wt%) grew to subconfluent monolayers but retained histiotypic morphological and physiological characteristics of lacrimal acinar cells in vivo. Our results suggest that mpPLLAm fabricated using this technique may be useful as a scaffold for a bioartificial lacrimal gland device.
为了最终开发出组织工程化泪液分泌系统，我们发现生长在固体聚（L-乳酸）（PLLA）载体上的原代泪腺腺泡细胞表现出最佳的组织形态学特征。然而，为了能够执行向量运输功能，上皮细胞必须由可渗透的基质支撑。在本研究中，我们描述了一种使用溶剂浇铸/颗粒沥滤技术从PLLA/聚乙二醇共混物制备微孔PLLA膜（mpPLLAm）的方法。扫描电子显微镜显示mpPLLAm的空气固化面（约4微米）和玻璃固化面（<2微米）上均有孔隙。对由57.1% PLLA/42.9%聚乙二醇共混物制成的mpPLLAm进行了扩散研究，以确认通道化孔隙的存在。数据显示葡萄糖、L-色氨酸和葡聚糖（一种高分子量葡萄糖聚合物）很容易透过mpPLLAm。免疫球蛋白G通过mpPLLAm的扩散随时间减少，表明孔隙可能存在吸附和堵塞现象。在mpPLLAm（57.1/42.9 wt%）上培养的细胞生长至亚汇合单层，但保留了体内泪腺腺泡细胞的组织形态学和生理特征。我们的结果表明，使用该技术制备的mpPLLAm可能作为生物人工泪腺装置的支架。
