PO.TB04.06 · 肿瘤生物学
用于全面评估T细胞接合器的集成临床前平台
An integrated preclinical platform for comprehensive evaluation of T-Cell engagers
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
T细胞接合器(TCEs)是一类双特异性抗体,设计用于同时结合T细胞上的CD3和癌细胞上的肿瘤相关抗原(TAA),代表了一类有前景的免疫疗法。鉴于其作用机制复杂,具有生理相关性的临床前模型对于准确评估TCE候选药物的疗效和安全性特征至关重要。我们开发了一组中通量至高通量的体外检测方法,基于靶点结合、T细胞活化和肿瘤细胞杀伤能力来筛选TCEs。先导候选药物进一步在异种移植和同基因模型中通过体内疗效研究进行评估。在异种移植研究中,我们使用了NCG小鼠和NCG-MHC-dKO小鼠——后者是通过在NCG背景中删除小鼠MHC I类和II类基因而产生的——以减少人PBMC植入后的移植物抗宿主病(GvHD)并延长实验观察期。AMG509(靶向STEAP1)、AMG757(靶向DLL3)和IBI-389(靶向CLDN18.2)分别在前列腺癌、小细胞肺癌和患者来源异种移植(PDX)模型中进行了评估。在同基因研究中,我们使用了BALB/c-hCD3EDG小鼠,其中内源性Cd3e、Cd3d和Cd3g基因被替换为人源版本。这些小鼠植入A20-hCD20淋巴瘤细胞以检测CD3/CD20双特异性抗体。
AMG509和AMG757均在PBMC人源化的NCG和NCG-MHC-dKO模型中显著抑制肿瘤生长,且对动物健康无重大不良影响。AMG509的疗效在STEAP1表达水平不同的前列腺癌细胞系中有所差异。在接受AMG757治疗的NCI-H69荷瘤小鼠中,肿瘤应答程度与治疗后三周观察到的人免疫细胞重建程度相关。IBI-389在两个胃癌PDX模型和一个胰腺癌PDX模型中表现出显著的肿瘤生长抑制。在BALB/c-hCD3EDG同基因模型中,给予CD3/CD20双特异性抗体在18天后导致81.5%的肿瘤生长抑制。
GemPharmatech的集成策略——将体外筛选与NCG、NCG-MHC-dKO和CD3人源化小鼠等一系列体内模型相结合——能够快速、可扩展且具有转化相关性地评估T细胞接合器候选药物。这一全面的平台支持稳健、高效的免疫肿瘤学药物发现与开发。
查看英文原文 English abstract
T-cell engagers (TCEs) are bispecific antibodies designed to bind both CD3 on T cells and a tumor-associated antigen (TAA) on cancer cells, representing a promising class of immunotherapies. Given their complex mechanisms of action, physiologically relevant preclinical models are essential for accurately evaluating the efficacy and safety profiles of TCE candidates. We developed a panel of medium- to high-throughput in vitro assays to screen TCEs based on target binding, T-cell activation, and tumor cell killing capabilities. Lead candidates were further assessed using in vivo efficacy studies in both xenograft and syngeneic models. In xenograft studies, we utilized NCG mice and NCG-MHC-dKO mice-the latter generated by deleting murine MHC class I and II genes in the NCG background-to reduce graft-versus-host disease (GvHD) after human PBMC engraftment and extend the experimental observation period. AMG509 (targeting STEAP1), AMG757 (targeting DLL3), and IBI-389 (targeting CLDN18.2) were evaluated in models of prostate cancer, small-cell lung cancer, and patient-derived xenografts (PDX), respectively. For syngeneic studies, we used BALB/c-hCD3EDG mice, in which endogenous Cd3e, Cd3d, and Cd3g genes were replaced with human versions. These mice were engrafted with A20-hCD20 lymphoma cells to test a CD3/CD20 bispecific antibody.
Both AMG509 and AMG757 significantly suppressed tumor growth in PBMC-humanized NCG and NCG-MHC-dKO models, with no major adverse effects on animal health. The efficacy of AMG509 varied across prostate cancer cell lines with different levels of STEAP1 expression. In NCI-H69 tumor-bearing mice treated with AMG757, the degree of tumor response correlated with the extent of human immune cell reconstitution observed three weeks post-treatment. IBI-389 exhibited marked tumor growth inhibition in two gastric cancer PDX models and one pancreatic cancer PDX model. In the BALB/c-hCD3EDG syngeneic model, administration of the CD3/CD20 bispecific antibody led to 81.5% tumor growth inhibition after 18 days.
GemPharmatech's integrated strategy-combining in vitro screening with a range of in vivo models such as NCG, NCG-MHC-dKO, and CD3-humanized mice-enables rapid, scalable, and translationally relevant assessment of T-cell engager candidates. This comprehensive platform supports robust and efficient immuno-oncology drug discovery and development.
利益披露 Disclosure
H. Sun, None..
X. Lian, None..
S. Guo, None..
Y. Zhang, None..
H. Yang, None..
X. Gao, None.