卡介苗体外对急性淋巴细胞性白血病患儿细胞毒性T淋巴细胞杀伤HL-60细胞效应的影响

Effect of bacillus Callmette-Guérin on cytotxicity of cytotoxic T lymphocyte from children with acute lymphoblastic leukemia for killing HL-60 cells in vitro

目的探讨卡介苗(BCG)体外对急性淋巴细胞性白血病(ALL)患儿外周血细胞毒性T淋巴细胞(CTL)杀伤HL-60细胞效应的影响。方法应用Ficoll-Hypaque法分离ALL患儿(白血病组)和健康儿童(对照组)的外周血单个核细胞,在白介素-2(IL-2)、植物血凝素(PHA)和BCG作用下诱导成CTL细胞;应用流式细胞仪测定CD3、CD3+CD4+、CD3+CD8+比例变化;应用MTT法检测CTL对HL-60细胞的杀伤力。结果培养前2 d,对照组和白血病组CTL细胞数量及体积均无明显变化,第3天开始两组细胞均开始增殖,体积变大,6～10 d达高峰;培养至第10天时,加入BCG的白血病组和对照组细胞数量分别较无BCG的白血病组和对照组增多;白血病组CD3+CD8+比例明显高于对照组,经BCG作用后两组CD3+CD8+比例均明显升高;白血病组CTL对HL-60细胞的杀伤力明显低于对照组。结论 BCG可协同IL-2、PHA体外促进CTL细胞增殖并提高其对HL-60细胞的杀伤力。

Objective To study the effect of bacillus Callmette-Guérin（BCG） on cytotxicity of cytotoxic T lymphocyte（CTL） from human peripheral blood of children with acute lymphoblastic leukemia（ALL） for killing HL-60 cells in vitro. Methods The mononuclear cells were isolated from peripheral blood of ALL children and healthy children,and were cultured with RPMI1640,interleukin-2（IL-2）,phytohemagglutinin（PHA） and BCG.The growth of CTLs was observed by light microscopy.The proportions of CD3,CD3＋CD4＋ and CD3＋CD8＋ were determined by flow cytometry 10 days after culture.MTT method was performed to detect the cytotoxicity of CTLs for killing HL-60 cells. Results Neither the cell number nor the volume of CTLs changed significantly within 2 days of culture,but both began increasing on the 3rd day of culture and reached a peak on the 6-10th days.On the 10th day of culture,the cell number of CTLs in the BCG treatment group was much higher than in the group without BCG treatment.The CD3＋CD8＋ proportion in the leukemia group was much higher than in the control group.With the effect of BCG,the CD3＋CD8＋ proportion of the two groups became much higher.The cytotoxicity of CTLs for killing HL-60 cells in the leukemia group was weaker than in the control group. Conclusions BCG along with IL-2 and PHA promotes the proliferation of CTLs and enhances the ability of CTLs in killing HL-60 cells.