131I-rituximab对B细胞淋巴瘤细胞生物学效应的实验研究

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AnnexinV—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 AnnexinV—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）：^131ⅠI-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

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 apoptosis rate measured by Annexin V-FITC/PI was 51.99% in 131I-rituximab group, significantly higher than that in 131I group, rituximab group and control group (42.71%, 29.42% and 26.17%, respectively, P<0.05). The apoptosis 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). 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.