固相MICA协同s4-1BBL、IL-15体外高效扩增CD3+CD56+细胞的研究

摘要

Objective: To investigate whether immobilized MHC class Ⅰ chain-related protein A (MICA) could synergize with soluble 4-1BBL and IL-15 to promote expansion of peripheral CD3 and CD56 double positive cells ex vivo.Methods: Peripheral blood mononuclear cells or purified CD3 + CD56 + cells were stimulated with immobilized MICA, s4-1BBL, and IL- 15 for 19 days.Frequencies of CD3 + CD56 + cells or the absolute cell numbers were observed during this long-term culture period.Next cytotoxicity and IFN-γ, IL-4 production of the expanded CD3 + CD56 + cells were detected by the LDH releasing assay and ELISA, respectively.Lastly, expression of function-associated receptors on CD3+ CD56+ cells was analyzed.Results:With 19-day culture,frequency of CD3+ CD56+ cells arrived from 2％ to 21.7％ on the average,and CD3+ CD56+ cells conld expand with 32 folds meanly.In addition, the long-term cultured CD3 + CD56+ cells were showed higher cytotoxicity and more production of IFN-γ, and could not secrete IL-4.Activating receptors were up-regulated to be present on the cultured CD3 +CD56+ cells whereas inhibitory receptors were decreased.Conclusion: Immobilized MICA in combination with soluble 4-1BBL and IL-15 not only promotes high expansion of CD3 + CD56 + cells, but also enhances function of CD3 + CD56 + cells.The culture system we developed here may be used in tumor adoptive immunotherapy.%目的:观察固相MHC Ⅰ类相关抗原A(iMICA)是否协同s4-1BBL、IL-15促进外周血CD3+CD56+细胞的增殖并增强其活性.方法:首先将iMICA联合s4-1BBL、IL-15分别刺激外周血单个核细胞或纯化的CD3+CD56+细胞,共培养19天,动态观察CD3+CD56+细胞频率变化及记录其增殖曲线;其次利用LDH释放法和ELISA分别检测长期培养的CD3+CD56+细胞杀伤活性及IFN-?、IL-4的分泌;最后检测CD3+CD56+细胞表面活性相关受体的表达.结果:iMICA 联合s4-1BBL、IL-15促进CD3+CD56+细胞的频率自2%升高至21.7%,绝对细胞数平均增长32倍;扩增后的CD3+CD56+细胞杀伤K562活性明显增高,IFN-?分泌能力增强,不分泌IL-4;其表面活化性受体表达上调,抑制性受体表达下调.结论:iMICA联合s4-1BBL、IL-15能高效扩增CD3+CD56+细胞,体外大量增殖后可用于肿瘤的过继免疫治疗.