Zhao Rongqing, Xiao Qian, Li Maohua, Ren Wenlin, Xia Chenxi, Liu Xudong, Li Yingzi, Tan Tan, Wu Dianqing, Sun Le
AbMax BioPharmaceuticals Co., LTD, Beijing 101111, China.
AnyGo Technology Co., LTD, Beijing 100122, China.
Antib Ther. 2020 Apr;3(2):63-70. doi: 10.1093/abt/tbaa004. Epub 2020 Apr 13.
Dickkopf-related protein 2 (DKK2)is a member of the Dickkopf family in Wnt signaling pathway. Recently, we found that antibodies against DKK2 could activate natural killer (NK) and CD8+ T cells in tumors and inhibit tumor growth. In this paper, we report the rational design of peptides for identification of linear epitopes and generation of neutralizing monoclonal anti-DKK2 antibodies. To break the immune tolerance, we designed and chemically synthesized six peptides corresponding to different regions of DKK2 as immunogens and found five of them could generate mouse polyclonal antibodies that can bind to the active recombinant human DKK2 protein. Neutralizing mouse monoclonal antibodies (5F8 and 1A10) against human DKK2 were successfully developed by immunizing the mice with two different peptides (KLNSIKSSL and KVWKDATYS) conjugated to Keyhole limpet hemocyanin (KLH). The monoclonal antibodies not only abolish DKK2's suppression of Wnt signaling in vitro but also inhibits tumor growth in vivo. Currently, those two mAbs are undergoing humanization as immunotherapy candidates and may offer a new drug for treatment of human cancers.
Dickkopf相关蛋白2（DKK2）是Wnt信号通路中Dickkopf家族的一员。最近，我们发现抗DKK2抗体可激活肿瘤中的自然杀伤（NK）细胞和CD8 + T细胞，并抑制肿瘤生长。在本文中，我们报告了用于鉴定线性表位和产生中和性抗DKK2单克隆抗体的肽的合理设计。为了打破免疫耐受，我们设计并化学合成了六种对应于DKK2不同区域的肽作为免疫原，发现其中五种可产生能与活性重组人DKK2蛋白结合的小鼠多克隆抗体。通过用与钥孔血蓝蛋白（KLH）偶联的两种不同肽（KLNSIKSSL和KVWKDATYS）免疫小鼠，成功开发了针对人DKK2的中和性小鼠单克隆抗体（5F8和1A10）。这些单克隆抗体不仅在体外消除了DKK2对Wnt信号的抑制作用，而且在体内也抑制了肿瘤生长。目前，这两种单克隆抗体正在进行人源化改造，作为免疫治疗候选药物，可能为人类癌症治疗提供一种新药。
