中文摘要：

目的：研究抗CD20嵌合抗体片段Fab’突变体诱导B淋巴细胞凋亡的发生、凋亡相关基因表达以及细胞内钙离子的浓度变化。方法：以人B淋巴细胞（Raji细胞）为凋亡细胞模型，通过MTT法、Westernblot和流式细胞仪等方法观察bcl-2／bax基因表达、细胞色素c及胞内Ca^2＋的变化。结果：抗CD20嵌合抗体片段Fab’突变体对Raji细胞生长增殖具有明显的抑制作用，并呈剂量依赖性。细胞中bcl-2表达有微弱的下降，而bax表达明显升高，并出现细胞色素c的释放和胞内Ca^2＋浓度的升高。结论：抗CD20嵌合抗体片段Fab’突变体诱导Raji细胞凋亡，与bcl2／bax表达、细胞色素c的释放和胞内Ca^2＋浓度的升高有关。

英文摘要：

Objective：To investigate the effect of chimeric anti-CD20 antibody Fab＇fragment on apoptosis, apoptosis related genes expression, and intracellular Ca^2＋ concentration of B lymphoma cells. Methods.. The proliferation of human B lymphoma cell line Raji was measured by MTT assay. The release of cytochrome c and expression of bcl-2/bax was detected by Western blotting. Apoptosis of Raji cells was determined by FACS analysis. Intracellular calcium concentration was measured by fluorescence method. Results：Chimeric anti-CD20 antibody Fab＇ fragment inhibited proliferation of Raji cells in a dose-dependent manner, slightly down-regulated bcl-2 protein expression, but significantly up-regulated bax expression. Cytochrome c was released and intracellular Ca^2＋ concentration was increased. Conclusion：Chimeric anti-CD20 antibody Fab＇ fragment induced apoptosis of Raji cells which was related with changes of bcl-2/bax, release of cytochrome c, and increase in intracellular Ca^2＋ concentration.