A novel format for recombinant antibody-interleukin-2 fusion proteins exhibits superior tumor-targeting properties in vivo.
A novel format for recombinant antibody-interleukin-2 fusion proteins exhibits superior tumor-targeting properties in vivo.
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重组抗体-白介素-2 融合蛋白的新形式在体内表现出优异的肿瘤靶向特性。
DOI：
10.18632/oncotarget.27726
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发表时间：
2020-10-13
期刊：
影响因子：
--
通讯作者：
Villa A
中科院分区：
文献类型：
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作者：
Ongaro T;Gouyou B;Stringhini M;Corbellari R;Neri D;Villa A
将 IL-2 靶向递送至肿瘤作为增强 T 细胞和 NK 细胞在疾病部位作用的途径而受到关注。我们之前已经描述了使用非共价同源二聚体双抗体形式将纤连蛋白 EDB 结构域特异性的 L19 抗体与人白细胞介素 2 融合。在这里，我们描述了 L19-IL2 融合的四种新型形式，其特点是抗体和 IL2 的不同排列。使用放射性碘标记蛋白在荷瘤小鼠中进行的比较定量生物分布分析表明，新形式（L19L19-IL2，单链双抗体形式的抗体）表现出最佳的生物分布结果。外周血单核细胞的体外测定显示，当使用单个 IL2 结构域时，调节性 T 细胞的激活减少。在体内，L19-IL2 和 L19L19-IL2 均抑制免疫活性小鼠癌症模型中的肿瘤生长。 T 细胞分析显示，用 L19-IL2 和 L19L19-IL2 治疗的小鼠中 CD4+ 和 FoxP3+ 细胞水平相似，CD8+ T 细胞扩增。 L19L19-IL2 与小鼠特异性 PD-1 阻断剂联合使用时，CD4+ 调节性 T 细胞的百分比显着降低。总的来说，这些数据表明新的 L19L19-IL2 形式表现出良好的肿瘤归巢特性，并在体内介导有效的抗癌活性。
The targeted delivery of interleukin-2 to the tumor is gaining attention as an avenue to potentiate the action of T and NK cells at the site of disease. We have previously described the fusion of the L19 antibody, specific to the EDB domain of fibronectin, with human interleukin-2, using a non-covalent homodimeric diabody format. Here, we describe four novel formats for the L19-IL2 fusion, featuring different arrangements of antibody and IL2. A comparative quantitative biodistribution analysis in tumor-bearing mice using radioiodinated proteins revealed that the novel format (L19L19-IL2, with the antibody in single-chain diabody format) exhibited the best biodistribution results. In vitro assays on peripheral blood mononuclear cells showed a decrease activation of regulatory T cells when single IL2 domain was used. In vivo, both L19-IL2 and L19L19-IL2 inhibited tumor growth in immunocompetent mouse models of cancer. T-cell analysis revealed similar levels of CD4+ and FoxP3+ cells, with an expansion of the CD8+ T cell in mice treated with L19-IL2 and L19L19-IL2. The percentage of CD4+ regulatory T cells was markedly decreased with L19L19-IL2 combined with a mouse-specific PD-1 blocker. Collectively, these data indicate that the new L19L19-IL2 format exhibits favorable tumor-homing properties and mediates a potent anti-cancer activity in vivo.