低剂量辐射对白血病小鼠肿瘤细胞凋亡的影响

目的研究低剂量辐射（LDR）后不同时间白血病小鼠血清肿瘤坏死因子（TNF）和骨髓白血病细胞凋亡的变化．为低剂量全身辐射辅助治疗白血病提供实验研究基础方法将体外培养扩增的WEHI-3细胞尾静脉注射接种于BALB／c小鼠体内，诱导移植性粒单白血病发生：60只成功建立的粒单白血病模型小鼠，实验组和对照组各30只．对照组小鼠不予LDR，实验组小鼠同时给予75mGy的LDR。于LDR后1d，2d，3d，5d和10d分别处死6只实验组及6只对照组小鼠，取其血清及骨髓，放射免疫分析法检测TNF，荧光显微镜、电镜观测骨髓白血病细胞的凋亡情况。结果LDR后不同时间小鼠血清TNF水平有不同程度的变化，1d和2d升高最为显著（P〈0．05），LDR后10d血清TNF水平已接近对照组（P〉0．05）。LDR后第2天、第3天骨髓白血病细胞凋亡率最高，第5天和第10天次之（P均〈0．05），骨髓白血病细胞凋亡率的变化略滞后于血清TNF的变化。结论LDR可使白血病小鼠血清TNF水平显著升高、骨髓白血病细胞凋亡率增加，LDR对小鼠粒单白血病的治疗是积极、有效的。

The Effect of Whole Body Low Dose Radiation on Apoptosis of Mice Leukemia Cell

Objective To investigate the effect caused by low dose radiation (LDR) on the level of tumor necrosis factor(TNF)and apoptosis of leukemia cell in myelomonocytic leukemia mice.Stimulatory effect of LDR on immune function is to be illuminated in this study in order to provide an experimental basis for auxiliary therapy on leukemia.Methods WEHI-3 cells were injected into BALB/c mice through tail veins to make an experimental animal model of myelomonocytic leukemia.60 leukemia models were used.30 animal models were irradiated with LDR of 75mGy at the same time and the others were not.6 animal models with LDR and 6 animal models without LDR would be killed at the time the 1st day,the 2nd day,the 3rd day,the 5th day and the 10th day after LDR in order to extract serum samples and bone marrow.The level of TNF and apoptosis percentage of leukemia cell in bone marrow were examined.Results There was remarkable difference between the mice which were killed at different time.The level of TNF was the highest on the 1st day and the 2nd day(P<0.05)and declined after that.The percentase of leukemia cell apoptosis was raised after LDR and went to top on the 2nd day and the 3rd day.Conclusion LDR could significantly increase the level of TNF and apoptosis percentage of leukemia cell in bone marrow.It shows that LDR is effective on leukemia mice recovery.