肿瘤血管导向肽与人突变IL-2融合蛋白的克隆、表达及生物学活性分析

摘要

Objective To obtain the fusion protein of recombinant mutant human IL-2 and a tumor-targeting peptide and study its biological activity. Methods Constructed a fusion gene of rmhIL-2 and a tumor-targeting peptide NGR cDNA and cloned into expression vector pET-22b( + ). After identification by sequencing, the recombinant vector was transformed into E. coli BL21 (DE3)for expression under induction of IPTG. The product of expression was purified, naturalized and identified. Results The product of expression presented in a form of inclusion body and more than 40% of total bacterial protein was the recombinant protein. The purified fusion protein rmhIL-2-NGR showed an immunogenicity on Western blot and a biological activity on CTLL-2 proliferative assay. Conclusion The fusion gene of rmhIL-2 and a tumor-targeting peptide can be successfully cloned and expressed. The expressed product shows biological activity and provids a chance for tumor targeting therapy.%目的获得具有生物学活性的与肿瘤血管导向肽(NGR)融合表达的突变人IL-2蛋白.方法将突变人IL-2与NGR的融合基因重组到表达载体pET-22b(+)并转化E.coli BL21(DE3),测序正确后,IPTG诱导表达,并对产物进行纯化、复性和鉴定.结果目的蛋白以包涵体形式存在,占菌体总蛋白的40%以上,Western blot分析显示纯化后的目的蛋白具有免疫结合活性,CTLL-2细胞增殖实验证明具有生物学活性.结论具有生物学活性的与肿瘤血管导向肽融合表达的重组人IL-2蛋白可成功地克隆并表达,为进一步的肿瘤导向治疗打下基础.