人胚胎干细胞（hESC）无饲养层培养体系由培养基和细胞基质两部分组成。目前国际通用的细胞基质为动物源性物质，当中所含的动物源成分和不明物质不利于研究者对hESC分子机制的研究以及未来hESC的临床应用。项目申请人在前期工作中首创性地发现小鼠胚胎成纤维细胞（MEF）和人包皮成纤维细胞（HFF）混合铺皿后通过冻融法制成的胞外基质能很好地支持hESC生长，本项目将在此基础上筛选出这种基质中发挥作用的蛋白成分，研究其支持hESC生长的分子机制，并以此蛋白为胞外基质建立新的、成分明确的无饲养层培养体系。这项工作将揭示细胞外基质对hESC体外培养中自我更新能力维持的作用机制，本项目探索建立的成分明确的培养体系有利于研究hESC体外增殖和分化的生化特征及分子生物学机制，并且为将来hESC进入临床应用创造条件。

The feeder-free culture system of human embryonic stem cell (hESC) is composed of culture medium and extracellular matrix (ECM). At present, the internationally used extracellular matrices are derived from animal cells. Components of animal origin and unknown substances are not helpful for researchers to study the molecular mechanism of hESC and the clinical application of hESC in the future. In the previous study, the applicant initiatively found that mixed ECM derived from mouse embryonic fibroblasts (MEF) and human foreskin fibroblasts (HFF) by freeze-thaw method could support the application of hESC. Based on the finding, the project will screen the crucial ingredients of mixed ECM that suppot the feeder-free growth of hESC, investigate the potential mechanism, and develop the new defined feeder-free culture system of hESC. The study will reveal the mechanism of extracellular matrix in maintaining self-renewal ability of hESC. The defined feeder-free culture system of hESC developed in this project is helpful to investigate biochemical characteristics and molecular mechanism of the proliferation and differentiation of hESC in vitro and create conditions for the clinical application of hESC in the future.