中文摘要：

目的：构建以IL-3为靶向、力达霉素（lidamycin,LDM）为弹头的融合蛋白IL-3-LDM,观察其对多种CD123＋白血病细胞的靶向杀伤作用。方法：原核表达IL-3-LDP（interleukin 3-lidamycin）融合蛋白,组装活性烯二炔（active enediyne,AE）发色团得到IL-3-LDM。流式细胞术检测不同白血病细胞系（KG1-a、TF-1、M07e、HL-60、K562、Raji）表面CD123分子的表达,并检测融合蛋白IL-3-LDM与各白血病细胞的结合能力;CCK-8检测IL-3-LDM融合蛋白对不同CD123阳性率的白血病细胞的杀伤能力。结果：组装活性发色团得到的IL-3-LDM蛋白纯度可达90%以上。急性髓系白血病（acute myeloid leukemia,AML）KG-1a细胞表面CD123阳性率最高（88.9%）,其次为MO7e和TF-1细胞（〉75%）,再次为HL-60细胞（7.8%）,而K562、Raji细胞CD123表达呈阴性。体外IL-3-LDM融合蛋白对CD123＋白血病细胞（KG-1a、MO7e、TF-1和HL-60细胞）的结合能力和杀伤效率与细胞表面CD123的阳性率成正比,对于CD123表达率最高的KG-1a细胞,LDM的杀伤强度是多柔比星（adriamycin,ADR）的1 415.8倍,而IL-3-LDM的杀伤强度又是LDM的9.6倍。结论：IL-3-LDM融合蛋白可以有效携带细胞毒药物LDM并高效靶向杀伤CD123＋白血病细胞。

英文摘要：

Objective：To construct a fusion protein IL-3-1idamycin （IL-3-LDM） with an IL-3 guide and a LDM war- head, and to investigate its targeting eytotoxieity on CD123 ~ leukemia cells in vivo. Methods： IL-3-LDP （interlekin 3-1i- damyein） fusion protein was obtained in a prokaryotic system, and further assembled with active enediyne （AE） to get IL- 3-LDM. The expression of CD123 in six leukemia cell lines （KGI-a, TF-1, M07e, HL-60, K562, Raji） was detected by flow cytometry and the binding ability of IL-3-LDM with different leukemia cell lines was examined. The cytotoxieity of IL-3-LDM fusion protein on leukemia cells with different CD123 expression levels was detected by CCK-8. Results： The purity of recombinant protein IL-3-LDM was more than 90% after assembling with AE. The results showed that the CD123 expression ratio was 88.9% on AML （acute myeloid leukemia） KG-la cells, 〉75% on MO7e and TF-1 cells, 7.8% on HL-60 ceils, and negative on K562 and Raji cells. The expression ratio of CD123 on leukemia cells （KG-la, MO7e, TF-1 and HL-60）was positively related to its binding ability and sensitivity to IL-3-LDM in vitro. The cytotoxicity of LDM on KG-la cells which expressed the highest level of CD133 was 1 415.8 fold stronger than that of adriamjcin （ADR）, and the cytotoxicity of IL-3-LDM was 9.6 fold than that of LDM. Conclusion： IL-3-LDM fusion protein can effectively target cytotoxic drug LDM to kill CD123 ^＋ leukemia cells.