Oxygen as a master immunologic switch

氧气作为主要免疫开关

• 批准号: 8505412
• 负责人: CHRISTOPHER A PENNELL
• 金额: $ 29.45万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-09 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8505412
• 关键词: ANXA2 gene; Adjuvant; Affect; Age; Antibodies; Antibody Formation; Antigens; B-Lymphocytes; Binding; Biological Assay; Brain Neoplasms; Breast Carcinoma; CD8B1 gene; Cancer Etiology; Cell Culture Techniques; Cells; Cessation of life; Clinic; Clinical; Clinical Trials; Complex; Cross Presentation; Cross-Priming; Cultured Tumor Cells; Cytotoxic T-Lymphocytes; Data; Dendritic Cells; Enhancing Antibodies; Fc Receptor; Figs - dietary; Foundations; Glioblastoma; Glioma; Goals; Harvest; Human; Hypoxia; Hypoxia Inducible Factor; Immune response; Immunoglobulin G; Immunologics; Immunotherapy; Knowledge; Ligands; Malignant Glioma; Malignant Neoplasms; Malignant neoplasm of brain; Mediating; Methods; Modeling; Molecular; Morbidity - disease rate; Mus; Nervous System Neoplasms; Oxygen; Oxygen measurement, partial pressure, arterial; Patients; Property; Recombinants; Relative (related person); Research Personnel; Rest; Role; Site; Source; Survival Rate; System; T-Lymphocyte; TLR2 gene; Testing; Therapeutic; Toll-Like Receptor 2; Toxic effect; Treatment Efficacy; Vaccinated; Vaccination; Vaccine Antigen; Vaccine Production; Vaccines; Work; bHLH-PAS factor HLF; base; cancer cell; cancer immunotherapy; cell killing; cytokine; immunogenicity; improved; in vivo; loss of function; lymphocyte proliferation; mouse model; neoplastic cell; novel; novel vaccines; response; tissue culture; trafficking; translational approach; tumor; vaccine efficacy

DESCRIPTION (provided by applicant): Malignant brain tumors are the leading cause of cancer-related death in people under the age of 35. Immunotherapy in the form of personalized vaccines has demonstrated immunologic activity and clinical responses in select glioma patients with minimal toxicity. There are numerous ongoing clinical trials that utilize cultured tumor cells as the source of vaccine antigen for the treatment of a wide array of tumors. However, very little is known about how cell culture conditions affect the immune response and ultimate clinical response following vaccination. The consistent condition used is expansion of tumor cells in atmospheric oxygen (20% O2). We have identified the oxygen concentration used in tissue culture as a primary determinant of the immunogenicity of tumor cell vaccines. Our data have led to the attractive central hypothesis that the oxygen tension in a tumor cell culture acts as a master immunologic switch, dictating the type and strength of immune response induced by vaccination. We have reproducibly shown that lysates from glioma cells cultured in 5% O2 prime cytotoxic T lymphocytes (CTLs) with superior effector functions relative to lysate from glioma cells cultured in 20% O2 in human and murine systems. This difference profoundly affects the efficacy of immunotherapy, as shown by significant improvements in survival in murine models of glioma and breast carcinoma. We demonstrated that administration of 5% O2 lysate vaccination caused superior CTL proliferation, cytokine elaboration, tumoricidal function, and trafficking to tumor sites relative to 20% O2 lysate vaccines. Conversely, 20% O2 lysate vaccines enhance antibody responses. Despite reduced tumor-reactive antibody responses, the 5% O2 vaccines require B cells for therapeutic efficacy, revealing a putative role of B cells in CTL priming. Additionally, we have evidence that glioma cells grown in 5% O2 upregulate toll-like receptor (TLR) 2 ligands because TLR2 is required in several systems to distinguish the immunogenicity of 5% and 20% O2 lysates. The goal of this proposal is to elucidate the molecular basis of the "oxygen switch effect" in order to rationally improve the efficacy of tumor cell vaccines. In specific aim 1 we will determine and optimize tumor cell intrinsic changes that modulate immunogenicity. Pharmacologic strategies to increase hypoxia inducible factors (HIF) in tumor cells will be compared to actual hypoxia in cell cultures that will subsequently be assayed for immunogenicity. Additionally, we will test the hypothesis that HIF2a is the molecular switch that induces expression of TLR2 ligands. In specific aim 2, we will test our hypothesis that B cells are required because IgG-tumor lysate complexes trigger Fc receptor-mediated cross presentation of antigens to enhance CTL responses. In specific aim 3, we will determine if the adjuvant effect of 5% O2 lysates is due to expression of Annexin A2, a novel putative TLR2 ligand we recently found to be upregulated in hypoxia. Collectively, this knowledge will facilitate groundbreaking approaches to enhance the efficacy of immunotherapy for glioma and other non-central nervous system tumors.

描述（由申请人提供）：恶性脑肿瘤是 35 岁以下人群癌症相关死亡的主要原因。个性化疫苗形式的免疫治疗已在选定的神经胶质瘤患者中表现出免疫活性和临床反应，且毒性最小。有许多正在进行的临床试验利用培养的肿瘤细胞作为疫苗抗原的来源来治疗多种肿瘤。然而，人们对细胞培养条件如何影响免疫反应和疫苗接种后最终临床反应知之甚少。使用的一致条件是肿瘤细胞在大气氧气（20% O2）中扩增。我们已经确定组织培养中使用的氧气浓度是肿瘤细胞疫苗免疫原性的主要决定因素。我们的数据得出了一个有吸引力的中心假设，即肿瘤细胞培养物中的氧张力充当主免疫开关，决定疫苗接种诱导的免疫反应的类型和强度。我们已重复证明，在人类和小鼠系统中，与在 20% O2 中培养的神经胶质瘤细胞裂解物相比，在 5% O2 Prime 细胞毒性 T 淋巴细胞 (CTL) 中培养的神经胶质瘤细胞裂解物具有更优异的效应功能。这种差异深刻地影响了免疫疗法的疗效，胶质瘤和乳腺癌小鼠模型的生存率显着提高就表明了这一点。我们证明，与 20% O2 裂解物疫苗相比，5% O2 裂解物疫苗接种可导致更出色的 CTL 增殖、细胞因子合成、杀肿瘤功能以及向肿瘤部位的运输。相反，20% O2 裂解物疫苗可增强抗体反应。尽管肿瘤反应性抗体反应减少，5% O2 疫苗仍需要 B 细胞来发挥治疗功效，这揭示了 B 细胞在 CTL 启动中的假定作用。此外，我们有证据表明，在 5% O2 中生长的神经胶质瘤细胞上调 Toll 样受体 (TLR) 2 配体，因为多个系统需要 TLR2 来区分 5% 和 20% O2 裂解物的免疫原性。该提案的目标是阐明“氧开关效应”的分子基础，以合理提高肿瘤细胞疫苗的功效。在具体目标 1 中，我们将确定并优化调节免疫原性的肿瘤细胞内在变化。增加肿瘤细胞缺氧诱导因子（HIF）的药理学策略将与细胞培养物中的实际缺氧进行比较，随后将进行免疫原性测定。此外，我们将测试 HIF2a 是诱导 TLR2 配体表达的分子开关的假设。在具体目标 2 中，我们将检验我们的假设，即需要 B 细胞，因为 IgG-肿瘤裂解物复合物会触发 Fc 受体介导的抗原交叉呈递以增强 CTL 反应。在具体目标 3 中，我们将确定 5% O2 裂解物的佐剂作用是否是由于膜联蛋白 A2 的表达所致，膜联蛋白 A2 是我们最近发现的一种新型推定 TLR2 配体，在缺氧条件下表达上调。总的来说，这些知识将促进突破性的方法来提高神经胶质瘤和其他非中枢神经系统肿瘤的免疫治疗的疗效。