Zhang T, Chen M L, Liu X Y, He H Z, Xu Y X, Tian Z, Xing H Y, Tang K J, Rao Q, Wang M, Wang J X
State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Tianjin Key Laboratory of Cell Therapy for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China.
Zhonghua Xue Ye Xue Za Zhi. 2022 May 14;43(5):376-382. doi: 10.3760/cma.j.issn.0253-2727.2022.05.005.
To investigate the effect of CD33-targeted bi-specific and tri-specific T-cell engagers on T-cell proliferation and explore their cytotoxicity on leukemia cells. The CD33-targeted bi-specific T-cell engager (CD33-BiTE) and tri-specific T-cell engager (CD33-TriTE) expression vectors were successfully constructed and expressed through a eukaryotic cell expression system. CD33-BiTE and CD33-TriTE were purified by affinity chromatography. The effects of CD33-BiTE and CD33-TriTE on T cells were analyzed through in vitro experiments. ① CD33-BiTE and CD33-TriTE were successfully constructed and purified and could compete with flow cytometry antibodies for binding to the target cells. ② After 12 days of co-culture with CD33-BiTE and CD33-TriTE, the number of human T cells were expanded to 33.89±19.46 and 81.56±23.62 folds, respectively. CD33-TriTE induced a stronger proliferation of T cells than CD33-BiTE (<0.05) . ③ Both CD33-BiTE and CD33-TriTE induced specific dose-dependent cytotoxicity on CD33(+) leukemia cells. ④ Compared to CD33-TriTE, leukemia cells were prone to express PD-L1 when co-cultured with T cells and CD33-BiTE. CD33-TriTE induced powerful cytotoxicity on leukemia cells with high PD-L1 expression. CD33-BiTE and CD33-TriTE expression vectors were constructed, and fusion proteins were expressed in eukaryotic cells. Our results support the proliferative and activating effects of BiTE and TriTE on T cells. Compared to that of CD33-BiTE, CD33-TriTE induced a stronger proliferative effect on T cells and a more powerful cytotoxicity on leukemia cells with high PD-L1 expression.
研究CD33靶向双特异性和三特异性T细胞衔接子对T细胞增殖的影响，并探讨其对白血病细胞的细胞毒性。通过真核细胞表达系统成功构建并表达了CD33靶向双特异性T细胞衔接子（CD33-BiTE）和三特异性T细胞衔接子（CD33-TriTE）表达载体。通过亲和层析法纯化CD33-BiTE和CD33-TriTE。通过体外实验分析CD33-BiTE和CD33-TriTE对T细胞的影响。①成功构建并纯化了CD33-BiTE和CD33-TriTE，它们可与流式细胞术抗体竞争结合靶细胞。②与CD33-BiTE和CD33-TriTE共培养12天后，人T细胞数量分别扩增至33.89±19.46倍和81.56±23.62倍。CD33-TriTE诱导的T细胞增殖比CD33-BiTE更强（<0.05）。③CD33-BiTE和CD33-TriTE均对CD33(+)白血病细胞诱导了特异性剂量依赖性细胞毒性。④与CD33-TriTE相比，白血病细胞在与T细胞和CD33-BiTE共培养时更容易表达PD-L1。CD33-TriTE对高表达PD-L1的白血病细胞诱导了强大的细胞毒性。构建了CD33-BiTE和CD33-TriTE表达载体，并在真核细胞中表达了融合蛋白。我们的结果支持BiTE和TriTE对T细胞的增殖和激活作用。与CD33-BiTE相比，CD33-TriTE对T细胞诱导了更强的增殖作用，对高表达PD-L1的白血病细胞诱导了更强的细胞毒性。
