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

摘要:

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。

Abstract:

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.