急性T淋巴细胞白血病(T-ALL)是一种可能发生在儿童和成人人群中的白血病。与急性B淋巴细胞白血病(B-ALL)相比,T细胞T-ALL患者的治疗效果较差.在这项研究中,一种新型抗CD7抗体-药物偶联物(ADC,J87-Dxd)成功生成并用于T-ALL治疗。首先,为了获得抗CD7单克隆抗体,我们表达并纯化了CD7蛋白胞外域。利用杂交瘤技术,我们获得了三种对CD7具有高亲和力的抗CD7mAb(J87,G73和A15)。免疫荧光和Biacore测定的结果均表明,J87(KD=1.54×10-10M)在三种抗CD7mAb中具有最高的亲和力。此外,内化实验显示,J87的内化水平高于其他两种mAb.接下来,我们通过可切割的马来酰亚胺-GGFG肽接头将DXd与J87缀合,成功产生了抗CD7ADC(J87-Dxd).J87-Dxd还具有识别和结合CD7的能力。使用J87-Dxd治疗T-ALL细胞(Jurkat和CCRF-CEM),我们观察到与CD7结合的J87-Dxd被内化到T-ALL细胞中。此外,J87-Dxd处理显著诱导Jurkat和CCRF-CEM细胞凋亡。通过CCK-8测定获得的J87-Dxd对CCRF-CEM的IC50(半最大抑制浓度)值为6.3nM。最后,为了评估J87-Dxd在体内的抗肿瘤功效,我们建立了T-ALL小鼠模型并用J87-Dxd或J87治疗小鼠。结果表明,在肿瘤接种后第24天,所有用J87或PBS治疗的小鼠死亡,而用J87-Dxd处理的小鼠的存活率为80%。H&E染色显示心脏没有明显的器质性变化,肝脏,脾,脾所有小鼠的肺和肾脏。总之,我们证明了新型抗CD7ADC(J87-Dxd)在体外和体内对表达CD7的T-All细胞具有有效的选择性作用,因此有望进一步开发为治疗T-ALL或其他CD7表达肿瘤的新药。
Acute T-lymphoblastic leukemia (T-ALL) is a type of leukemia that can occur in both pediatric and adult populations. Compared to acute B-cell lymphoblastic leukemia (B-ALL), patients with T-cell T-ALL have a poorer therapeutic efficacy. In this study, a novel anti-CD7 antibody-drug conjugate (ADC, J87-Dxd) was successfully generated and used for T-ALL treatment. Firstly, to obtain anti-CD7
mAbs, we expressed and purified the CD7 protein extracellular domain. Utilizing hybridoma technology, we obtained three anti-CD7
mAbs (J87, G73 and A15) with a high affinity for CD7. Both the results of immunofluorescence and Biacore assay indicated that J87 (KD = 1.54 × 10-10 M) had the highest affinity among the three anti-CD7
mAbs. In addition, an internalization assay showed the internalization level of J87 to be higher than that of the other two
mAbs. Next, we successfully generated the anti-CD7 ADC (J87-Dxd) by conjugating DXd to J87 via a cleavable maleimide-GGFG peptide linker. J87-Dxd also possessed the ability to recognize and bind CD7. Using J87-Dxd to treat T-ALL cells (Jurkat and CCRF-CEM), we observed that J87-Dxd bound to CD7 was internalized into T-ALL cells. Moreover, J87-Dxd treatment significantly induced the apoptosis of Jurkat and CCRF-CEM cells. The IC50 (half-maximal inhibitory concentration) value of J87-Dxd against CCRF-CEM obtained by CCK-8 assay was 6.3 nM. Finally, to assess the antitumor efficacy of a J87-Dxd in vivo, we established T-ALL mouse models and treated mice with J87-Dxd or J87. The results showed that on day 24 after tumor inoculation, all mice treated with J87 or PBS died, whereas the survival rate of mice treated with J87-Dxd was 80%. H&E staining showed no significant organic changes in the heart, liver, spleen, lungs and kidneys of all mice. In summary, we demonstrated that the novel anti-CD7 ADC (J87-Dxd) had a potent and selective effect against CD7-expressing T-All cells both in vitro and in vivo, and could thus be expected to be further developed as a new drug for the treatment of T-ALL or other CD7-expression tumors.