PO.IM01.07 · 免疫学
表面工程化NK/曲妥珠单抗细胞作为HER2低表达乳腺癌的新型免疫疗法
Surface engineered-NK/trastuzumab cells as a novel immunotherapy for HER2-low breast cancer
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
目的：HER2低表达乳腺癌占大多数转移性病例，其治疗仍然充满挑战。尽管曲妥珠单抗-德鲁替康（trastuzumab-deruxtecan）已显示出临床获益，但其应用受到高毒性和疾病进展的限制，这凸显了对更安全、更有效、更易获得的靶向选择的需求。这些肿瘤对弱势群体的影响尤为严重，加剧了医疗护理中的不平等。在我们此前构建的鼠源HER2低表达模型和NK/曲妥珠单抗（Tz）表面工程平台的基础上，我们现在评估了SE-NK/Tz细胞对HER2低表达的人源和鼠源肿瘤（包括3D肿瘤球体）的治疗潜力和选择性。
方法：通过使用疏水连接子将25 μg的Tz嵌入鼠源LNK细胞或人源NK92细胞表面，生成SE-NK细胞，并通过流式细胞术和共聚焦成像验证偶联效率。在4T1-HER2低表达鼠源细胞（本实验室构建）和HER2低表达MDA-MB-175人源乳腺癌细胞的2D和3D培养中，通过基于荧光素酶的杀伤实验评估HER2特异性细胞毒性。使用HER2阴性细胞评估特异性。
结果：与未修饰的NK细胞相比，SE-LNK/Tz细胞对4T1-HER2低表达靶细胞表现出显著增强的细胞毒性（在E:T 10:1时为86 ± 1 % vs 55 ± 2 %，p < 0.0001），并在多个效靶比（20:1至2.5:1）下保持一致。SE-NK92/Tz细胞对MDA-MB-175靶细胞的细胞毒性也同样增强（在E:T 1:1时为57 ± 1% vs 42 ± 3 %，p < 0.01）。重要的是，SE-NK/Tz细胞对HER2阴性细胞的杀伤明显较低（小鼠6 ± 5% vs 69 ± 2%；人42 ± 1% vs 57 ± 1 %，p < 0.0001），证实了HER2特异性靶向。SE-LNK/Tz细胞在3D球体实验中保持活性，表明其具有有效的肿瘤穿透能力。
结论：本研究将我们的表面工程NK平台从概念验证推进到在鼠源和人源HER2低表达系统（包括3D培养模型）中的功能验证。SE-NK/Tz细胞对HER2低表达乳腺癌显示出强效且具选择性的细胞毒性，支持其作为该弱势患者群体新一代低毒性免疫疗法的潜力。正在进行的工作着重于探索在多种体内HER2低表达模型中的免疫激活机制和治疗疗效。
查看英文原文 English abstract
Purpose: HER2-low breast cancers, which account for most metastatic cases, remain challenging to treat. Although trastuzumab-deruxtecan has shown clinical benefit, its use is limited by high toxicity and disease progression, underscoring the need for safer, more effective, and more accessible targeted options. These tumors disproportionately affect underserved populations, amplifying disparities in care. Building upon our previous development of a murine HER2-low model and NK/Trastuzumab (Tz) surface-engineering platform, we now evaluated the therapeutic potential and selectivity of SE-NK/Tz cells against HER2-low human and murine tumors, including 3D tumor spheroids.
Methods: SE-NK cells were generated by embedding 25 µg of Tz onto the mouse-derived LNK cells or human NK92 cells using a hydrophobic linker, and conjugation efficiency was verified by flow cytometry and confocal imaging. HER2-specific cytotoxicity was evaluated by luciferase-based killing assays in 2D and 3D cultures of 4T1-HER2-low murine cells (generated in our lab) and HER2-low MDA-MB-175 human breast cancer cells. HER2-negative cells were used to assess specificity.
Results: SE-LNK/Tz cells exhibited significantly enhanced cytotoxicity against 4T1-HER2-low targets (86 ± 1 % vs 55 ± 2 %, p < 0.0001 at E:T 10:1), consistent across multiple effector-to-target ratios (20:1-2.5:1), compared with unmodified NK cells. SE-NK92/Tz cells similarly increased cytotoxicity against MDA-MB-175 targets (57 ± 1% vs 42 ± 3 %, p < 0.01 at E:T 1:1). Importantly, SE-NK/Tz cells showed markedly lower killing of HER2-negative cells (mouse 6 ± 5% vs 69 ± 2%; human 42± 1% vs 57± 1 %, p < 0.0001), confirming HER2-specific targeting. SE-LNK/Tz cells maintained activity in 3D spheroid assays, indicating effective tumor penetration.
Conclusions: This study advances our surface-engineering NK platform from proof-of-concept to functional validation in both murine and human HER2-low systems, including 3D culture models. SE-NK/Tz cells display potent and selective cytotoxicity against HER2-low breast cancer, supporting their potential as a next-generation, low-toxicity immunotherapy for this underserved patient population. Ongoing work focuses on exploring mechanisms of immune activation and therapeutic efficacy in diverse in vivo HER2-low models.
利益披露 Disclosure
M. Godoy Calderon, None..
M. Patwardhan, None..
S. Sethi, None..
E. Gauchat, None.