为给细胞株基因工程改造提供背景条件，文中以TNFR-Fc为模式蛋白，比较两株不同来源的CHO-DG44细胞在生长代谢以及外源蛋白TNFR-Fc表达方面的差异，采用iTRAQ结合2D LC-MS/MS技术，比较CHO-DG44 （A）/TNFR-Fc和CHO-DG44 （B）/TNFR-Fc细胞株的蛋白表达谱，并对差异蛋白进行了蛋白类型分析、差异基因GO富集分析和差异基因KEGG富集分析。结果表明：两株CHO细胞在生长代谢及外源蛋白表达方面存在一定的差异；通过对比蛋白表达谱发现的192种差异表达蛋白中，上调蛋白104个、下调蛋白88个；就蛋白类型而言，酶类所占的比例最多，达到38.02%；差异蛋白主要富集在包括蛋白质折叠、谷胱甘肽代谢过程、碳水化合物代谢过程、细胞内蛋白质转运、蛋白质稳定化等生物过程；差异蛋白主要涉及氨基酸的生物合成、碳代谢、糖酵解/糖异生、三羧酸循环等信号通路。不同CHO细胞株在氨基酸的生物合成、碳代谢、糖酵解/糖异生等方面的蛋白差异，可能是引起两株细胞生长代谢以及外源蛋白表达方面的差异的原因。

To provide the background for the genetic engineering modification of cell line, this paper compared two CHO-DG44 cells from different sources in terms of their differences in growth, metabolism and expression of exogenous protein TNFR-FC. ITRAQ combined with 2D LC-MS/MS were used to compare the protein expression profiles between CHO-DG44(A)/TNFR-FC cell, line and CHO-DG44 (B)/TNFR-Fc cell line, and protein-variety, GO enrichment and KEGG enrichment analysis were performed on the differential expression proteins. The results show that there are differences in cell growth, metabolism and exogenous protein expression between the two CHO cells. By comparing the protein expression profiles, it is found that there are 104 up-regulated proteins and 88 down-regulated proteins among 192 differentially expressed proteins. And enzymes accounted for the largest proportion (38.02%) among these differential proteins. The differentially expressed proteins are mainly enriched in biological processes like protein folding, glutathione metabolic process, carbohydrate metabolic process, intracellular protein transport, protein stabilization. These differential proteins are mainly related to pathways such as biosynthesis of amino acids, carbon metabolism, glycolysis/gluconeogenesis, citrate cycle, pyruvate metabolism and other signaling pathways. The differences in growth and metabolism, and expression of exogenous proteins between these two cell lines may be explained by the protomic differences in amino acid biosynthesis, carbon metabolism, glycolysis/gluconeogenesis, etc.