人K562白血病细胞来源的树突状细胞低温冻存方法的研究

本研究的目的是探讨经低温保存的树突状细胞 (dendriticcell,DC)的生物学特性 ,寻找一种较为简便有效的冻存方式 ,为DC的临床过继回输提供保存方法。将由K5 62细胞诱导培养产生的DC(K5 62 DC) ,用含 10 %二甲亚砜 (DMSO)及 2 0 %胎牛血清 (FCS)的RPMI 1640作为冻存剂 ,利用分步法分别将其冻存于 - 80℃冰箱及- 196℃液氮中 ,然后于不同时间将K5 62 DC复苏 ,复苏后检测两组细胞的存活率、表面分子表达、刺激指数及其介导CTL对K5 62细胞的杀伤率 ,比较冻存前后及两组间的差异。结果发现 ,冻存前后K5 62 DC (K5 62 DC于- 80℃或液氮冻存 1月 )细胞形态无明显变化 ,表面分子表达及刺激T细胞增殖的能力无明显差别 (P >0 .0 5 )。此外 ,在 - 80℃冰箱及 - 196℃液氮中冻存的K5 62 DC ,在冻存后 1月以内复苏 ,细胞的存活率、刺激T细胞增殖的能力及其介导的杀伤效应无差别 ;但当冻存时间超过 1月时 ,两组间有明显差别。结论 ,两种冻存方式冻存K5 62 DC ,冻存时间较短时 ( 1月以内 ) ,其刺激淋巴细胞及其介导CTL的杀伤能力相同 ;冻存时间较长时 ( >1月 ) ,- 196℃液氮效果明显优于 - 80℃超低温冰箱。

Study on Cryopreservative Methods for Dendritic Cells Derived from K562 Cell Line

To investigate the biological properties of cryopreserved dendritic cell (DC) derived from K562 cell line, thus to provide a simple, quick and efficient preservative method of DC for infusion of DC to patients with leukemia after complete remission, fresh DC induced from K562 cell line (K562-DC) was frozen in -196 degrees C liquid nitrogen and -80 degrees C mechanical freezer by method of steps (RPMI 1640 with 10% DMSO, 20% FCS as cryopreservatives), and thawed in different time, respectively. Survivals of cryopreserved and fresh K562-DC, expression of surface antigens, stimulating index (SI) and cytotoxic eliminating rate were detected. The results of fresh induced cells were compared with that of cryopreserved ones. The results showed that before and after frozen in liquid nitrogen, the morphological characteristics of K562-DC had no distinct change; and both their expression rates of surface molecular and capacity to stimulate allogeneic lymphocyte had no statistic significance (P > 0.05). In addition, there were no differences in terms of viability, stimulatory capacity and cytotoxicity of K562-DC from two ways for less than one month (P > 0.05), but there were differences when frozen for more than one month (P < 0.05). It is concluded that there is no significant difference when frozen less than one month between liquid nitrogen and -80 degrees C freezer; but when time is more than one month, K562-DC frozen in -196 degrees C liquid nitrogen is better than that in -80 degrees C freezer.