Engineering Siglec15/TGF-beta targeted bispecific antibodies that modulate the tumor microenvironment and enhances T-cell immunotherapy against pancreatic cancer

工程化 Siglec15/TGF-β 靶向双特异性抗体可调节肿瘤微环境并增强针对胰腺癌的 T 细胞免疫治疗

• 批准号: 10651442
• 负责人: Samuel Lai
• 金额: $ 21.49万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10651442
• 关键词: Abbreviations; Affinity; Agreement; Animals; Antibodies; Avidity; B-Lymphocytes; Binding; Bispecific Antibodies; Bite; C57BL/6 Mouse; CD3 Antigens; CD8-Positive T-Lymphocytes; CTLA4 gene; CXCL13 gene; Cancer Etiology; Cells; Cessation of life; Characteristics; Data; Disease; Dose; Drug Delivery Systems; Effectiveness; Engineering; Epithelial Cells; Fab domain; Goals; Growth; Human; Image; Immune; Immune Evasion; Immune checkpoint inhibitor; Immunocompetent; Immunoglobulin G; Immunoglobulin M; Immunosuppression; Immunosuppressive Agents; Immunotherapy; Infiltration; Lead; Leukocytes; Light; Macrophage; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of pancreas; Mammary Neoplasms; Measures; Mediating; Mesenchymal; Modeling; Molecular; Mus; Myeloid Cells; Myeloid-derived suppressor cells; Nature; Pancreas; Pancreatic Ductal Adenocarcinoma; Patients; Peripheral Blood Mononuclear Cell; Pilot Projects; Production; Publications; Regulatory T-Lymphocyte; Resistance; Signal Transduction; Stromal Cells; Suppressor-Effector T-Lymphocytes; Survival Rate; T cell response; T-Cell Activation; T-Cell Proliferation; T-Lymphocyte; Therapeutic; Toxic effect; Transforming Growth Factor beta; Tumor Cell Migration; Tumor Promotion; Tumor Suppression; Tumor-associated macrophages; Vascularization; Work; Xenograft Model; bi-specific T cell engager; bioprocess; chemotherapy; cytokine; design; effective therapy; improved; knock-down; luminescence; melanoma; monocyte; mortality; mouse model; nanomedicine; nuclear factors of activated T-cells; overexpression; pancreatic cancer cells; pancreatic cancer model; pancreatic cancer patients; pancreatic ductal adenocarcinoma cell; pancreatic neoplasm; programmed cell death ligand 1; response; safety assessment; subcutaneous; triple-negative invasive breast carcinoma; tumor; tumor growth; tumor microenvironment; tumor-immune system interactions

Pancreatic ductal adenocarcinoma (PDAC), which accounts for more than 90% of the pancreatic cancer cases, unfortunately has an average 5-year survival rate of less than 10%. To date, both chemotherapy and immunotherapy, including the checkpoint inhibitors like PD-L1, CTLA-4, has not been effective in treating PDAC. Although PDAC is infiltrated with leukocytes, they are mostly the suppressive types such as myeloid- derived suppressor cells, regulatory B cells, T regulatory cells and M2-macrophages, likely due to elevated levels of molecules such as TGF-β that suppresses T-cell activation. We have identified Siglec-15 (S15), which can directly inhibit NFKβ/NFAT signaling resulting in suppressed T-cell proliferation and cytokine production, as a critical immune suppressor in tumor microenvironment. Interestingly, S15 is broadly upregulated in various cancers, including triple negative breast cancers and PDAC, as well as tumor-associated macrophages, with no detectible expression in other healthy cells besides monocytes. Elevated expression of S15 is correlated with poor survival in PDAC patients. Importantly, Siglec15 is highly expressed in PDAC cells with low PD-L1, suggesting Siglec15 may be involved in immune evasion observed in PDL1-negative PDAC. Given the overexpression of S15 in PDAC, we hypothesized that a bispecific antibody (bsAb) that binds both S15 and an immune-suppressive cytokine (TGF-β) could result in greater bsAb accumulation in the tumor, and thus synergistically enhances T-cell activation for improved tumor suppression. We hypothesize that bispecific T-cell engagers (BiTE) that bind S15 and CD3 could likewise enhance T-cell immunotherapy against PDAC, including breaking down the stromal barrier. In pilot studies, our S15/TGF-β bsAb afforded much more effective tumor suppression than a cocktail of anti-S15 and anti-TGF-β Ab in mouse model of triple negative breast cancer. Likewise, S15/CD3 BiTE effectively suppressed pancreatic tumor in a xenograft model. Building off these promising findings, we seek to explore whether simultaneously modulation of the tumor immune microenvironment with improved T-cell targeting can lead to more effective therapy against PDAC. Towards this goal, we will engineer in Aim 1 a panel of bsAb that binds S15 while possessing different number of binding domains against TGF-β. We will evaluate whether the increased number of TGF-β binding domains further reduce immune suppression in the tumor leading to more effective therapy in an orthotopic pancreatic model in mice. In Aim 2, we will investigate whether the most potent S15/TGF-β bsAb from Aim 1 may synergistically enhance S15/CD3 BiTE therapy, both in an orthotopic human pancreatic cancer model in NSG mice infused with human PBMC and in a syngeneic orthotopic mice pancreatic cancer model. If successful, our work may lead to improved treatment options for management of PDAC, as well as advance an overall framework to enhance immunotherapy against different cancers.

胰腺导管腺癌（PDAC），占胰腺的90％以上 不幸的是，癌症病例的平均5年生存率低于10％。迄今为止，两种化疗 免疫疗法，包括PD-L1，CTLA-4等检查点抑制剂，尚未有效治疗 PDAC。尽管PDAC被白细胞浸润，但它们主要是抑制类型，例如髓样 衍生的抑制细胞，调节性B细胞，调节细胞和M2巨噬细胞，可能是由于升高 抑制T细胞激活的TGF-β等分子水平。 我们已经确定了SIGLEC-15（S15），它可以直接抑制NFKβ/NFAT信号，从而导致 抑制T细胞增殖和细胞因子的产生，作为肿瘤中的临界免疫抑制剂 微环境。有趣的是，S15在各种癌症中广泛上调，包括三重负乳房 癌症和PDAC以及与肿瘤相关的巨噬细胞，在其他健康中没有可检测的表达 除单核细胞以外的细胞。 S15的表达升高与PDAC患者的存活率差有关。 重要的是，SIGLEC15在PD-L1低的PDAC细胞中高度表达，这表明SIGLEC15可能涉及 在PDL1阴性PDAC中观察到的免疫进化中。 鉴于PDAC中S15的过表达，我们假设双特异性抗体（BSAB）是 结合S15和免疫抑制细胞因子（TGF-β）可能会导致BSAB在 肿瘤，因此协同增强了T细胞激活，以改善肿瘤抑制。我们假设 结合S15和CD3的双特异性T细胞Endager（咬）也可以增强T细胞免疫疗法 针对PDAC，包括打破基质屏障。在试点研究中，我们的S15/TGF-βBSAB提供 在三重小鼠模型中，抗S15和抗TGF-βAB的鸡尾酒比抑制肿瘤更有效。 阴性乳腺癌。同样，S15/CD3咬合有效地抑制了Xenographic模型中的胰腺肿瘤。 建立这些承诺发现，我们试图探索是否仅仅调节 肿瘤免疫微环境具有改进的T细胞靶向可以导致更有效的治疗 PDAC。为了实现这一目标，我们将在AIM 1中设计一个BSAB面板，该BSAB绑定了S15，同时拥有不同 与TGF-β的结合结构域的数量。我们将评估TGF-β结合数量的增加 域进一步减少肿瘤中的免疫抑制 小鼠胰腺模型。在AIM 2中，我们将研究AIM 1中最有效的S15/TGF-βBSAB 可以在原位的人类胰腺癌模型中协同增强S15/CD3叮咬疗法 感染了人类PBMC的NSG小鼠和合成原位小鼠胰腺癌模型。如果 成功，我们的工作可能会改善PDAC管理的治疗选择，并提高 总体框架以增强免疫疗法，以抵抗不同的取消。