摘要
目的比较免疫球蛋白κ轻链启动子/增强子和免疫球蛋白重链启动子/增强子控制的白喉毒素A链基因对淋巴瘤细胞生长抑制。方法将白喉毒素A链基因或细菌β半乳糖苷酶基因与免疫球蛋白启动子/增强子相连构建成白喉毒素A链真核表达载体pcDNA3IgκDTA、pcDNA3IgHDTA或细菌β半乳糖苷酶真核表达载体pcDNA3IgκLacZ、pcDNA3IgHLacZ。由脂质体介导将质粒转染至产或不产免疫球蛋白的真核细胞中,检测β半乳糖苷酶基因在不同细胞中的表达水平,并进一步检测白喉毒素A链基因的表达对转染细胞的生长抑制作用。结果由免疫球蛋白κ轻链启动子/增强子或免疫球蛋白重链启动子/增强子控制的β半乳糖苷酶基因只能在产免疫球蛋白(κ轻链型)细胞株CA46中表达。当β半乳糖苷酶基因与质粒pcDNA3IgκDTA或pcDNA3IgHDTA共转染时,β半乳糖苷酶基因的表达只在CA46细胞中被抑制。质粒pcDNA3IgκDTA、pcDNA3IgHDTA的表达均能明显抑制CA46细胞的生长,而对照质粒pcDNA3IgκLacZ或pcDNA3IgHLacZ对CA46细胞则无明显作用,并且pcDNA3IgκDTA的抑制作用较pcDNA3IgHDTA更强。结论由免疫球蛋白κ轻链启动子/增强子或免疫球蛋白重链启动子/增强子控制的白喉毒素A链基因的表达能特异性地杀伤产免疫球蛋白(κ轻链)的肿瘤细胞。并且免疫球蛋白κ轻链启动子/增强子较免疫球蛋白重链启动子/增强子有更强的启动转录活性。
Objective To test whether the diphtheria toxin A chain coding sequence linked to murine immunoglobulin K-light chain （IgK） or heavy chain（IgH） promoter and enhancer exert cytocidal effect selec- tively on IgKor IgH producing cells. Methods The mammalian expression vectors containing the diphtheria toxin A chain coding sequence, controlled by murine immunoglobulin K-light chain（IgK） or heavy chain（IgH） promoter and enhancer, were transfected into the lymphoma cell line CA46 by the liposome-coated DNA meth- od. Expression of β-galactosidase（β-gal） activity and effects on cell growth of transfected cells were assessed. Results Expression of [3-gal under the control of IgKor IgH promoter was detected only in immunoglobulin pro- ducing cell line CA46. Expression of β-gal was greatly suppressed when co transfected with pcDNA3IgKDTA or pcDNA3IgHDTA in CA46 cells. Cell growth of CA46 cells transfected with pcDNA3IgKDTA plasmid was signif- icantly inhibited compared with CA46 cells transfected with pcDNA3IgHDTA. Conclusion Selective killing of inununoglobulin producing cells can be attained by introducing the diphtheria toxin A gene under the control of of IKor IgH oromoter and enhancer, esoecially under the control of IgKor IgH promoter and enhancer.
出处
《中国实用医药》
2012年第16期1-4,共4页
China Practical Medicine
