PO.ET02.11 · 实验与分子治疗
基于白蛋白的DLL3靶向SN38纳米免疫偶联物在小细胞肺癌中保持效力并显示出高亲和力DLL3结合
Albumin-based DLL3-targeted nano-immunoconjugates of SN38 preserve potency and demonstrate high-affinity DLL3 binding in small cell lung cancer
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：小细胞肺癌(SCLC)仍是一种侵袭性恶性肿瘤，治疗选择有限，5年生存率低于10%。Delta样配体3(DLL3)在超过85%的SCLC中表达，但在正常组织中缺失，是一个有吸引力的治疗靶点。现有的DLL3导向抗体偶联药物存在载荷稳定性差和肿瘤穿透有限的问题。为克服这些局限，我们采用基于白蛋白的纳米支架，构建了一种DLL3靶向的SN38(伊立替康的活性代谢物)纳米免疫偶联物(NIC)。
方法：将SN38包封于人血清白蛋白(HSA)基质中，并以重组抗DLL3单克隆抗体进行非共价包被，制得DLL3-SN38-NIC。通过HSA-IgG相互作用和zeta电位变化确认了稳定的偶联。采用Biacore表面等离子体共振(SPR)和使用AHC生物传感器的Octet生物膜层干涉技术(BLI)评估了结合动力学，以测定DLL3-抗体的亲和力和特异性。使用IncuCyte活细胞成像在五种DLL3表达水平不同的SCLC细胞系(DMS454、SHP77、NCI-H82、NCI-H889和NCI-H211)中评估细胞毒性。
结果：DLL3-SN38-NIC保持了高亲和力的DLL3结合(KD≈3×10⁻¹⁰ M)，并在SCLC细胞系中显示出强效的细胞毒性。与游离SN38相比，NIC的形成未降低细胞毒活性，证实了效力的保持。在DLL3表达水平不同的各细胞系中，细胞毒性趋势一致，而单独的DLL3抗体表现出可忽略的细胞毒性。这些发现证实纳米免疫偶联物的形成维持了药物活性和DLL3结合；正在进行更多的体内研究以评估药代动力学和肿瘤选择性。
结论：基于白蛋白的DLL3-SN38-NICs代表了一种新型纳米肿瘤学平台，它保持了SN38的效力并实现了高亲和力的DLL3结合。正在进行的研究将评估其在DLL3阳性SCLC及其他神经内分泌恶性肿瘤中的体内选择性、生物分布和治疗潜力。
关键词：DLL3、纳米免疫偶联物、SN38、白蛋白纳米载体、小细胞肺癌
查看英文原文 English abstract
Background: Small cell lung cancer (SCLC) remains an aggressive malignancy with limited treatment options and a 5-year survival rate under 10%. Delta-like ligand 3 (DLL3), expressed in >85% of SCLC but absent from normal tissue, represents an attractive therapeutic target. Existing DLL3-directed antibody-drug conjugates suffer from poor payload stability and limited tumor penetration. To overcome these limitations, we engineered a DLL3-targeted nano-immunoconjugate (NIC) of SN38, the active metabolite of irinotecan, using an albumin-based nanoscaffold.
Methods: SN38 was encapsulated in a human serum albumin (HSA) matrix and non-covalently coated with a recombinant anti-DLL3 monoclonal antibody to yield DLL3-SN38-NIC. Stable conjugation was confirmed by HSA-IgG interactions and zeta-potential shift. Binding kinetics were evaluated using Biacore surface plasmon resonance (SPR) and Octet bio-layer interferometry (BLI) employing AHC biosensors to determine DLL3-antibody affinity and specificity. Cytotoxicity was assessed using IncuCyte live-cell imaging across five SCLC cell lines (DMS454, SHP77, NCI-H82, NCI-H889, and NCI-H211) with varying DLL3 expression.
Results: DLL3-SN38-NIC retained high-affinity DLL3 binding (KD ≈ 3 × 10⁻¹⁰ M) and demonstrated potent cytotoxicity in SCLC cell lines. NIC formation did not reduce cytotoxic activity compared with free SN38, confirming preserved potency. Cytotoxicity trends were consistent across lines with variable DLL3 expression, and DLL3 antibody alone exhibited negligible cytotoxicity. These findings confirm that nano-immunoconjugate formation maintains drug activity and DLL3 binding; additional in-vivo studies are underway to evaluate pharmacokinetics and tumor selectivity.
Conclusions: Albumin-based DLL3-SN38-NICs represent a novel nano-oncologic platform that preserves SN38 potency and achieves high-affinity DLL3 engagement. Ongoing studies will assess in-vivo selectivity, biodistribution, and therapeutic potential in DLL3-positive SCLC and other neuroendocrine malignancies.
Keywords: DLL3, nano-immunoconjugate, SN38, albumin nanocarrier, small cell lung cancer
利益披露 Disclosure
M. Shanshal,
Mayo clinic Employment, Mayo clinic.
Center for clinical and translation science grant from mayo clinic ), Center for clinical and translation science grant from mayo clinic.
L. Geng, None..
W. Nevala, None.
B. Wootla,
Mayo clinic Mayo clinic Business Development.
K. Korshavn,
Mayo clinic Employment.