摘要
目的探讨血管内皮生长因子(vascular endothelial cell growth factor,VEGF)对白血病源树突状细胞(dendrit-ic cell,DC)抗原提呈能力的影响及其分子机制。方法K562细胞经5μmol/LVEGF反义寡核苷酸(AS-ODN)处理24h,ELISA和免疫组化检测VEGF蛋白水平。以正常K562细胞诱生的白血病DC作为对照组,利用流式细胞术和混合淋巴细胞反应,观察AS-ODN处理的白血病DC的免疫表型及其刺激T细胞增殖的能力。采用荧光素酶检测系统和RT-PCR分析培养12h时白血病DC内NF-κB转录活性和Flt-1mRNA水平。结果AS-ODN处理使K562细胞VEGF蛋白分泌量较K562细胞组显著下降(P<0.05)。与K562-DC比较,AS-ODN处理的免疫表型(CD40、CD86、CD83、HLA-DR)表达明显上调。在不同DC/T值(1:10～1:40)时,MLR实验中AS-K562-DC组刺激指数(SI)明显高于对照组(P<0.05)。此外,培养12h时AS-K562-DCNF-κB转录活性较K562-DC明显增高(P<0.05),而Flt-1mRNA水平未见明显改变。结论反义寡核苷酸可抑制白血病细胞VEGF表达,下调VEGF能够增强白血病DC免疫表型的表达,提高DC抗原提呈能力。
Objective To investigate the effect of vascular endothelial growth factor （VEGF） on antigen presentation capability of dendritic ceils （DCs） derived from leukemic cell line. Methods After treated by 5 μmol/L VEGF antisense oligodeoxynucleotide （AS-ODN） for 24 h, VEGF protein expression of K562 cells was measured by ELISA and immunohistochemistry. Taking DCs induced from K562 as control, the biological characteristics of leukemic DCs derived from K562 treated by AS-ODN were examed. Flow cytometry was used to detect the expressions of immunophenotypes. The proliferative ability of T ceils stimulated by DCs was analyzed by mixed lymphocyte reaction assay. Moreover, luciferase assay system was used to monitor the transcription activity of NF-κB and RT-PCR to detect Flt-1 mRNA expression at the end of 12-hour culture. Results VEGF protein secretion of treated K562 decreased remarkably compared to K562 cell （ P 〈 0.05 ）. Compared to K562- DC group, the expressions of immunophenotypes including CD40, CD83, CD86 and HLA-DR in leukemic DCs group increased remarkably. The stimulating index （SI） of MLR in leukemic DCs group was significantly higher than that in the control group in different ratio of DC/T （ 1：10 to 1：40 ） respectively （ P 〈0.05 ）. At the end of 12-hour culture, the transcription activity of NF-κB of leukemic DCs was significantly higher （P 〈0. 05 ）, but Flt-1 mRNA level had no obvious change. Conclusion VEGF AS-ODN could inhibit VEGF protein level in leukemic cells in vitro. Downregulating VEGF could enhance the immunophenotype expressions of DCs derived from the leukemic cells and improve their antigen presentation capability.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2007年第16期1587-1590,共4页
Journal of Third Military Medical University
基金
重庆市教委科学技术研究基金(KJ050309)~~
关键词
白血病
血管内皮生长因子
反义寡核苷酸
树突状细胞
核因子ΚB
leukemia
vascular endothelial growth factor
antisense oligodeoxynucleotide
dendritic cells
nuclear factor κB
