^{关键词：B细胞淋巴瘤；放射免疫治疗；碘放射性同位素；Rituximab；Raji细胞；细胞凋亡}

    摘要：目的 研究¹³¹I标记的Rituximab对CD20高表达的B细胞淋巴瘤细胞的生物学效应，为放射免疫导向治疗提供实验依据。 方法 IODO-GEN法将¹³¹I标记于抗CD20单抗Rituximab，用Annexin Ⅴ-FITC/PI 双染法检测¹³¹I-Rituximab对Raji细胞的诱导凋亡作用，PI染色法检测细胞周期分布。 结果 Annexin Ⅴ-FITC/PI 双染法检测凋亡率：¹³¹I-Rituximab组凋亡率为51.99%，¹³¹I组为42.71%，Rituximab组为29.42%，对照组为26.17%。对照组和Rituximab组凋亡率明显低于¹³¹I组和¹³¹I-Rituximab组(P<0.05)。PI 染色法对比各组的凋亡率(亚二倍体峰)：¹³¹I-Rituximab组细胞凋亡率为4.32%，¹³¹I组为1.47%，Rituximab组为1.39%，对照组仅0.37%，¹³¹I-Rituximab组凋亡率明显高于其他各组(P<0.05)。¹³¹I-Rituximab组Raji细胞周期发生变化，细胞大部分被阻滞于G1/G2期。 结论 ¹³¹I-Rituximab能够调控Raji细胞的细胞周期并诱导其凋亡，从而抑制Raji细胞增殖。

    Biological response of B-cell lymphoma cells in vitro to ¹³¹I-Rituximab on

    WEI Li, LUO Rong-cheng, ZHANG Jun-yi, YAN Xiao, FANG Yong-xin, FEI Li-hua

    Center of Oncology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China

    Abstract: Objective To study the biological response of B-cell lymphoma cells positive for CD20 expression to ¹³¹I-labeled Rituximab. Methods Anti-CD20 monoclonal antibody Rituximab was labeled with ¹³¹I by means of IODO-GEN method, and its effects on apoptosis of Raji cells were determined by Annexin-V/PI double-labeled cytometry. Its effects on the cell cycles was evaluated by cytometry with PI staining. Results The cell apoptotic rate measured by Annexin Ⅴ-FITC/PI was 51.99% in ¹³¹I-Rituximab group, significantly higher than that in in ¹³¹I group, Rituximab group and control group (42.71%, 29.42% and 26.17%, respectively, P<0.05). The apoptotic rate by flow cytometry with PI staining was 4.32% in ¹³¹I-Rituximab group, also significantly higher than that in the other 3 groups (1.47%1.39% and 0.37%, respectively, P<0.05). The cell cycle alteration of Raji cells occurred in ¹³¹I-Rituximab group, and the majority of cells were arrested at G₁/G₂ stage. Conclusion ¹³¹I-Rituximab can regulate the cell cycle of Raji cells and induce their apoptosis to inhibit their proliferation. ......