Augmenting immune responses to DC-tumor fusions using local 3rd signals

描述（由申请人提供）： 尽管在手术、化疗和放射治疗方面取得了进展，但晚期头颈癌患者仍然存在局部复发和远处转移的高风险。这些癌症是毁灭性的，因为它们对多个器官系统和生活质量的影响。需要新的方法来改善这些患者的护理。 解决这些问题的一种策略是树突状细胞（DC）-肿瘤融合杂交免疫疗法。单次DC-肿瘤融合疫苗接种已显示介导小鼠中已建立肿瘤的消退。然而，成功的DC-肿瘤融合免疫疗法需要全身共施用IL-12。不幸的是，IL-12的临床应用受到毒性的限制。此外，免疫调节机制，如调节性T细胞（Treg）可能会限制基于DC-肿瘤融合的免疫疗法的全部有效性。这种免疫调节机制可以使用抗CTLA-4单克隆抗体（mAb）克服，但是这种mAb的全身施用是昂贵的并且与毒性相关，限制了这种方法的临床适用性。提出了一种使用DC-肿瘤融合物进行头颈癌免疫治疗的新方法，所述DC-肿瘤融合物将IL-12以及抗CTLA-4 mAb局部递送至DC-肿瘤融合物/T细胞相互作用的位点。 本申请的总体目标是优化DC-肿瘤融合杂合体诱导抗肿瘤应答的能力。中心假设是局部分泌IL-12的DC-肿瘤融合杂合体将刺激CD 4+和CD 8 + T细胞介导的抗肿瘤应答。此外，我们假设这些融合杂合体刺激抗肿瘤免疫的能力将通过DC-肿瘤融合体局部分泌抗CTLA-4 mAb而增强。将通过追求三个具体目标来测试该中心假设：1）通过用局部分泌IL-12的DC-肿瘤融合杂合体接种来诱导抗肿瘤CD 4+和CD 8+效应T细胞。鼠模型将用于测试DC-肿瘤融合体局部分泌IL-12将通过CD 4+和CD 8 + T细胞诱导肿瘤消退的假设; 2）通过局部消除Treg介导的免疫抑制进一步增强DC-肿瘤融合体杂合体刺激抗肿瘤免疫的能力。鼠模型将用于测试如下假设：通过DC融合物局部递送抗CTLA-4 mAb来消除Treg免疫抑制将导致增强的抗肿瘤免疫; 3）在人体外模型中，使用局部分泌IL-12和抗CTLA-4 mAb的DC-肿瘤杂合体诱导抗肿瘤CD 4+和CD 8+效应T细胞。人体外模型将检验以下假设：与单独使用任一种相比，分泌IL-12和抗CTLA-4 mAb的人DC-肿瘤融合杂合体将增强CD 4+和CD 8 + T细胞抗肿瘤应答。 Walter Lee博士（PI）非常熟悉当前头颈癌治疗的局限性和挑战。他致力于寻求免疫疗法来治疗这些癌症，并将工作重点放在树突状细胞（DC）-肿瘤融合杂交体上。他已经召集了合格的导师和顾问，以进一步发展他作为一个专注于DC-肿瘤融合免疫疗法的外科医生-科学家。李博士的职业发展计划包括教学课程和研讨会，这些课程和研讨会已融入他的实验室学习目标。他还将指导涉及DC-肿瘤融合杂交和其他免疫治疗方法的临床试验的设计，执行和数据分析。 通过这个VA职业发展奖-2（VA-CDA-2），李博士将阐明影响成功的DC-肿瘤融合的机制，并获得将实验室发现转移到临床试验所需的技能。此外，该VA-CDA-2将允许Lee博士建立基于VA的职业生涯，并使他能够成长为独立资助的外科医生科学家。 公共卫生相关性： 据估计，每年有35,000名退伍军人被诊断患有癌症。这使得癌症成为退伍军人死亡的第二大原因。在这些癌症中，晚期头颈癌由于其对呼吸，吞咽和说话的影响而特别虚弱。此外，由于先前或持续使用烟草和酒精，退伍军人患头颈癌的风险很高，这是公认的风险因素。尽管手术、化疗和放疗方式有所改善，但晚期头颈癌患者仍存在局部复发和远处转移的高风险。此外，现有治疗方案的副作用影响了退伍军人及其家人的生活质量。迫切需要新的和改进的治疗策略，不仅可以提高头颈癌患者的长期生存率，还可以提高其生活质量。本计画将探讨树突状细胞-肿瘤融合免疫疗法，以引导免疫细胞攻击肿瘤而无副作用。

DESCRIPTION (provided by applicant): Despite advances in surgery, chemotherapy, and radiation modalities, patients with advanced head and neck cancer continue to be at high risk for loco-regional recurrences and distant metastasis. These cancers are devastating due to their impact on multiple organ systems and quality of life. New approaches are needed to improve the care of these patients. One strategy to address these issues is dendritic cell (DC)-tumor fusion hybrid immunotherapy. A single DC-tumor fusion vaccination has been shown to mediate the regression of established tumors in mice. However, successful DC-tumor fusion immunotherapy has required the systemic co-administration of IL-12. Unfortunately, the clinical use of IL-12 is limited by toxicity. Furthermore, immune regulatory mechanisms such as regulatory T cells (Treg) may limit the full effectiveness of DC-tumor fusion-based immunotherapy. Such immune regulatory mechanisms can be overcome using anti-CTLA-4 monoclonal antibody (mAb), but systemic administration of this mAb is costly and associated with toxicity, limiting the clinical applicability of such an approach. A novel approach is proposed for the immunotherapy of head and neck cancer using DC-tumor fusions that locally deliver IL-12, as well anti-CTLA-4 mAb, to the site of DC-tumor fusion/T cell interactions. The overall objective of this application is to optimize the ability of DC-tumor fusion hybrids to induce anti-tumor responses. The central hypothesis is that DC-tumor fusion hybrids that locally secrete IL-12 will stimulate a CD4+ and CD8+ T cell mediated anti-tumor response. Furthermore, we hypothesize that the ability of these fusion hybrids to stimulate anti-tumor immunity will be enhanced by local secretion of anti-CTLA-4 mAb by the DC-tumor fusion. This central hypothesis will be tested by pursuing three specific objectives: 1) Induce anti-tumor CD4+ and CD8+ effector T cells through vaccination with DC-tumor fusion hybrids locally secreting IL-12. Murine models will be used to test the hypothesis that local secretion of IL-12 by the DC-tumor fusion will induce tumor regression via both CD4+ and CD8+ T cells; 2) Further enhance the ability of DC-tumor fusion hybrids to stimulate anti-tumor immunity by abrogating Treg-mediated immunosuppression locally. Murine models will be used to test the hypothesis that abrogating Treg immunosuppression through local delivery of anti-CTLA-4 mAb by the DC-fusion will result in enhanced anti- tumor immunity; 3) In a human in vitro model, induce anti-tumor CD4+ and CD8+ effector T cells using DC-tumor hybrids locally secreting IL-12 and anti-CTLA-4 mAb. Human in vitro models will test the hypothesis that human DC-tumor fusion hybrids secreting both IL-12 and anti-CTLA-4 mAb will potentiate the CD4+ and CD8+ T cell anti-tumor response compared with using either one alone. Dr. Walter Lee (PI) is intimately familiar with the limitations and challenges of current therapies for head and neck cancers. He has demonstrated a commitment to pursuing immunotherapy approaches to treating these cancers and has focused his work on dendritic cell (DC) - tumor fusion hybrids. He has assembled well qualified mentors and consultants to further his development as a surgeon-scientist focused on DC-tumor fusion immunotherapy. Dr. Lee's career development plan includes didactic courses and seminars that are integrated into his laboratory learning objectives. He will also be mentored in the design, execution, and data analysis of clinical trials that involve DC-tumor fusion hybrids and other immunotherapy approaches. Through this VA Career Development Award-2 (VA-CDA-2), Dr. Lee will elucidate mechanisms that influence successful DC-tumor fusion as well as obtain the skills needed to move laboratory findings to clinical trials. Furthermore, this VA-CDA-2 will allow Dr. Lee to establish a VA-based career and enable him to mature into an independently funded surgeon scientist. PUBLIC HEALTH RELEVANCE: There are an estimated 35,000 veterans a year diagnosed with cancer. This contributes to making cancer the second leading cause of death among veterans. Of these cancers, advanced head and neck cancer is especially debilitating due to its impact on breathing, swallowing, and speaking. Furthermore, veterans are at high risk for developing head and neck cancers due to prior or continued use of tobacco and alcohol, which are well established risk factors. Despite improvements in surgery, chemotherapy, and radiation modalities, patients with advanced head and neck cancer remain at high risk for loco-regional recurrence and distant metastasis. Furthermore, the side effects from available treatment options impact the quality of life of veterans and their families. New and improved treatment strategies are urgently needed to not only increase long term survival but also quality of life for patients with head and neck cancer. This proposal will investigate dendritic- cell - tumor fusion immunotherapy as a means to direct immune cells to attack tumor without side effects.