Zhang Yang, Zhang Pengyu, He Aili, Yang Yun, Wang Jianli, Zhang Hui, Zhang Wanggang
Department of Hematology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China.
Oncotarget. 2017 Jun 13;8(24):39077-39086. doi: 10.18632/oncotarget.16590.
MLAA-34 is a newly identified monocytic leukemia-associated antigen that is overexpressed in acute monocytic leukemia specifically, thus providing a novel target for the therapy of acute monocytic leukemia. In this study, we first expressed MLAA-34 protein in Escherichia coli (E.coli) BL21 (DE3) cells and purified it by nickel ion affinity chromatography with high purity (>90%). Then, MLAA-34 was used as antigen for biopanning anti-MLAA-34 single chain antibody fragment (ScFv) from a fully human ScFv library, and a high affinity ScFv named MA1 was selected by phage-ELISA. Finally, after expression of MA1, we found that MA1 can specifically bind with U937 MLAA-34 positive cells, and the binding affinity of MA1 was at the nanomolar level. Furthermore, inhibition of U937 cell proliferation indicated that the novel antibody MA1 has the potential to be used as a therapeutic agent for acute monocytic leukemia.
MLAA - 34是一种新发现的单核细胞白血病相关抗原，它在急性单核细胞白血病中特异性过表达，从而为急性单核细胞白血病的治疗提供了一个新靶点。在本研究中，我们首先在大肠杆菌BL21(DE3)细胞中表达MLAA - 34蛋白，并通过镍离子亲和层析将其纯化至高纯度(>90%)。然后，将MLAA - 34用作抗原，从全人源单链抗体片段(ScFv)文库中淘选抗MLAA - 34单链抗体片段，通过噬菌体酶联免疫吸附测定法筛选出高亲和力的单链抗体片段MA1。最后，在表达MA1后，我们发现MA1能与U937 MLAA - 34阳性细胞特异性结合，且MA1的结合亲和力处于纳摩尔水平。此外，对U937细胞增殖的抑制表明新型抗体MA1有潜力用作急性单核细胞白血病的治疗药物。
