GM—CSF基因修饰,抗原预激的树突状细胞体内诱导白血病细胞分化？…

目的：探讨树突状细胞在肿瘤治疗过程中的作用及机制。方法：以小鼠ＦＢＬ－３红白血病细胞皮下接种Ｃ５７ＢＬ／６小鼠建立荷瘤模型，采用流式细胞仪分析和透射电镜等技术，观察了粒－巨噬细胞集落刺激因子（ＧＭ－ＣＳＦ）基因修饰的抗原预激的树突状细胞体内治疗作用。结果：采用ＧＭ－ＣＳＦ基因修饰的抗原预激的树突状细胞治疗，可以明显抑制白血病细胞生长；白血病细胞表达ＣＤ３４水平增加，同时ＭＨＣ－Ⅱ，Ｂ７－１，Ｂ７－

Studies on the in vivo induction of differentiation of the erythroleukemia cells by the antigen-pulsed dendritic cells modified with GM-CSF gene]

OBJECTIVE: To investigate the function and mechanism of dendritic cells in the immunotherapy for tumors. METHODS: C57BL/6 mice inoculated with erythroleukemia cells were used as models. Inhibition or induction of tumor cell differentiation was observed by fluorescence-activated cell sorting (FACS) and transmission electron microscopy. RESULTS: After pulsed with FBL-3 antigen, the GM-CSF gene transfected dendritic cells inhibited the proliferation of the tumor cells. The expression of CD14 was increased and the expressions of MHC-II, B7-1, B7-2 and VCAM-1 were also up-regulated. Erythroleukemia cells in different differentiating stages were observed in tumor tissues. Under transmission electron microscope, the volumes of FBL-3 cells were reduced, the amount of lysosome and hetero-chromatin became plentiful, the nucleocytoplasmic ratio was decreased, and apoptosis was revealed in erythroleukemia cells. The CD8+ cells were increased in peripheral blood and tumor tissues. CONCLUSION: The antigen-pulsed dendritic cells modified with GM-CSF gene could induce in vivo the erythroleukemia cells to differentiate into monocytes.