重组人白介素2-穿孔蛋白免疫毒素的制备及功能活性

CONSTRUCTION OF hIL2-PERFORIN RECOMBINANT IMMUNOTOXIN AND ITS BIOACTIVITY

以人白细胞介素2为载体，人Perforin为毒素，利用基因工程技术构建成pBV221／IL2－Perforom表达质粒，在大肠杆菌中成功地表达出IL2－Perforin重组毒素，SDS－PAGE获得分子量的20KD的蛋白条带，细胞毒测定对活化的人T淋巴细胞和IL2依赖株CTLL2有明显的杀伤作用，并且明显抑制同种混合淋巴细胞反应，这是一种性质全新的重组毒素，其杀伤机制不同于以往所用的毒素（PE，DT等）。这种新的重组毒素不仅有益于器官移植，也可能对自身免疫病的治疗带来新的方法。

By using genetic engineering tech-nique, a hybrid cDNA coding for a fusion protein between human interleukin 2 and a truncated human per forin was constructed and expressed in E. coli.The protein encoding by this cDNA contains the en-tire interleukin 2 sequence, fused at its C terminal to the bioactive part of human perforin in the N-ter-minal portion. Cytotoxic assay showed that the IL2-Perforin could kill the IL2-dependent cell line CTLL2 and IL2 activated T cells efficiently, and in-hibit the allogenic mixed ymphocyte response signif-icantly. All these imply that the novel humanized immunotoxin IL2-Perorin may be a promise tool for specific immunosppression in humans.