白介素13与白喉毒素融合蛋白靶向治疗活性的研究

Targeted Killing Effect of IL-13 Diphtheria Toxin Fusion Protein and DT_(389)-hIL13-13E13K

目的研究白介素13与白喉毒素融合蛋白DT389-hIL13-13E13K对神经胶质瘤的靶向杀伤作用,为神经胶质瘤的无创性治疗和常规化疗的替代或补充治疗提供新的途径。方法通过诱导已构建的融合蛋白表达质粒,原核表达并获得IL-13与白喉毒素融合蛋白DT389-hIL13-13E13K。分别通过两种不同方法提纯后,用体内外实验研究不同浓度融合蛋白对神经胶质瘤的靶向杀伤活性。结果所得融合蛋白浓度纯度均达到95%以上。在体外活性实验中,两种复性纯化方法获得的融合蛋白DT389-hIL13-13E13K对神经胶质瘤均有很好的杀伤效果,半数抑制浓度(IC50)分别达到6×10-10mol/L和1×10-8mol/L,杀伤效果达到了国际水平。体内活性测定结果显示,融合蛋白DT389-hIL13-13E13K对神经胶质瘤有一定的抑制作用,但效果并未达到使肿瘤完全消退的水平。结论得到了在体内外都对神经胶质瘤有抑制杀伤作用的特异的靶向治疗融合蛋白。

Objective To study the targeted killing effect of IL - 13 diphtheria toxin fusion protein to glioma and to provide an alternative or an accessorial therapy for human glioma.Methods IL-13 and diphtheria toxin fusion protein （DT389 - hiL13 - 13E13K） was induced and expressed from designed plasmid in E. coli. After the fusion protein was refolded and purified by two different ways, the killing effect was evaluated at different concentration both in vitro and in vivo. Results The purity of the fusion protein DT389 - hiL13-13EI3K was over 95%. It significant killed the cancer cells in vitro, the concentration of DT389-hiL13-13E13K at which 50% inhibition（ IC50） occurred at 6 ×10^-10 mol/L （which is up to the international level） and 1×10-^-8 mol/L in the two different renaturation and purification methods, respectively. In the in vivo experiment, the tumors of the nude mice grew very low when they were injected with the fusion protein but not regressed. Conclusion The fusion protein has a targeted killing effect to glioma both in vivo and in vitro experiment.