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)，占胰腺癌的90%以上 不幸的是，癌症病例的平均5年存活率不到10%。到目前为止，这两种化疗 免疫疗法，包括像PD-L1，CTLA-4这样的检查点抑制剂，在治疗方面还没有效果 PDAC。虽然PDAC有白细胞浸润，但大多为髓系白血病等抑制性白细胞。 衍生的抑制细胞、调节性B细胞、T调节性细胞和M2-巨噬细胞，可能是由于 抑制T细胞活化的分子水平，如转化生长因子-β。 我们已经鉴定出Siglec-15(S15)，它可以直接抑制NFKβ/NFAT信号转导导致 抑制T细胞增殖和细胞因子的产生，作为肿瘤中的关键免疫抑制因子 微环境。有趣的是，S15在各种癌症中普遍上调，包括三重阴性乳腺癌 癌症和PDAC，以及与肿瘤相关的巨噬细胞，在其他健康人群中未检测到表达 除单核细胞外的其他细胞。在PDAC患者中，S15的高表达与生存不良相关。 重要的是，Siglec15在低PD-L1的PDAC细胞中高表达，提示Siglec15可能参与了这一过程 在PDL1阴性的PDAC中观察到免疫逃避。 鉴于S15在PDAC中的过表达，我们假设一个双特异性抗体(BsAb)可以 结合S15和免疫抑制细胞因子(转化生长因子-β)可导致更多的bsAb在 从而协同增强T细胞的激活，从而改善肿瘤抑制。我们假设 结合S15和CD3的双特异性T细胞结合蛋白(BITE)同样可以加强T细胞免疫治疗 针对PDAC，包括打破基质屏障。在试点研究中，我们的S15/转化生长因子-β单抗提供了 抗S15和抗转化生长因子-β单抗在三联模型小鼠体内的抑瘤作用 阴性乳腺癌。同样，在异种移植模型中，S15/CD3 BITE有效地抑制了胰腺肿瘤。 在这些有希望的发现的基础上，我们试图探索同时调制 具有改进的T细胞靶向性的肿瘤免疫微环境可以导致更有效的治疗 PDAC。为了这个目标，我们将在目标1中设计一组bsAb，它结合S15，同时拥有不同的 与转化生长因子-β结合的结构域数。我们将评估转化生长因子-β结合数量的增加 结构域进一步减少肿瘤中的免疫抑制，从而在原位治疗中更有效 小鼠胰腺模型。在目标2中，我们将研究来自目标1的最强的S15/转化生长因子-βbsAb 可协同增强S15/CD3咬合治疗，两者均在人胰腺癌原位模型中 NSG小鼠输注人PBMC和同种异体原位小鼠胰腺癌模型。如果 如果成功，我们的工作可能会改善PDAC的治疗方案，并促进 加强针对不同癌症的免疫治疗的总体框架。