微囊化重组CHO细胞制备和培养条件的优化

Preparation and Cultivation of Microencapsulated Recombinant CHO Cells

微囊化重组基因细胞移植治疗肿瘤是一种新兴的肿瘤基因治疗方法,然而由于目前微囊化细胞规模化制备和培养技术还不成熟,阻碍了其在临床治疗中的推广与应用。以重组CHO细胞为模型,考察了不同的微囊制备和培养条件对微囊化细胞生长和内皮抑素表达的影响。实验表明,种子细胞所处的生长阶段和细胞接种密度对微囊化细胞生长和内皮抑素表达的影响较大,对数生长期的细胞进行包囊并且细胞接种密度为1×106~2×106cells/mL微囊时微囊内细胞生长良好、内皮抑素表达量高。微囊制备时间对细胞活性和内皮抑素表达也有较大的影响,制备时间延长对细胞的损伤增大,因此制备时间应控制在5h以内。生物微胶囊在制备过程中会造成细胞损伤,而体外培养是恢复细胞活性的良好方法,在培养过程中微囊接种量为5%时对细胞生长和内皮抑素表达有利。

Transplantation of the microencapsulated recombinant cells is a novel alternative approach to gene therapy of tumors. The semiermeable membrane of microcapsule protects cells from host＇ s immune rejection, increases the efficiency of gene transfer and reduces the need for frequent injection. Optimization of the preparation and culture is needed to acquire biological microcapsule with high cell viability and protein production. In this work, we studied the effect of different preparation and culture condition on the microencapsulated recombinant CHO cells growth and endostatin production. The result showed that the inoculum cells growth phase and seeding density potently affected the growth and endostatin production of the recombinant CHO cells in the microcapsule. The exponential growth phase recombinant CHO cells with a seeding density of 1 × 10^6 - 2 × 10^6 cells/ mL microcapsules benefited to the cells growth and endostatin production. The time of preparation was another important effect factor of cells viability, the cells viability decreased with the increase of preparation time and the time of preparation should be under 5h for maintaining the cell viability and endostain production. The highest viable cell density and endostatin production was acquired when the microcapsule percentage was 5 % in the culture of the microencapsulated cells, the cell growth and endostatin production decreased with the increase of the microcapsule percentage.