Strategies to enhance thymus-independent T cell development in cancer patients

描述（由申请人提供）：绝大多数T细胞是在胸腺中产生的，胸腺是一种对放疗或化疗特别敏感的淋巴器官。因此，增强胸腺外T细胞发育的策略可能有助于改善造血干细胞移植、癌症、免疫抑制或某些病毒感染等疾病的结果。我之前在HSCT和恶性肿瘤的小鼠模型中进行了研究，证明了采用离体产生的T细胞（preT）进行过继细胞治疗以增强T细胞重建的可行性和有效性。我发现过继转移的preT可以用作“现成的”细胞疗法，并通过MHC屏障来增强胸腺再生和T细胞免疫。该提案的主要目标是开发策略，以提高胸腺非依赖性T细胞重建癌症患者，使用组织培养和组织工程为基础的免疫方法。我建议研究胸腺外位点对前T细胞来源的T细胞重建的贡献，并使用类似细胞外基质的三维生物可吸收聚合物支架开发用于T细胞发育的离体和体内组织结构。可生物降解的聚合物具有的优点是，它们可以用于制造用于体内移植的微米或纳米纤维三维基质，并且它们可以被分子定制以释放生物活性剂，从而导致高效的局部药物递送和细胞生长和分化的控制。将通过将工程化基质细胞-聚合物支架复合物或无细胞胸腺再生模板植入小鼠体内，然后分析细胞生长、分化、迁移和功能（包括抗肿瘤活性），在体外和体内研究T细胞发育。宿主和生物材料反应的表征还将包括植入物血管化、生物材料降解和植入炎症反应的分析。基于我的初步数据，使用一种改进的组织工程方法与优化的设计，生物材料的性能和细胞-生物材料的相互作用，我预计植入组织工程人工胸腺微环境将导致增强T细胞免疫，并将有助于肿瘤免疫监视。我的目标在未来五年内，在这个职业发展奖的帮助下，是建立自己作为一个医生，科学家在儿科血液学/肿瘤学领域，并获得终身职位的学术中心。作为一名医生，科学家，我希望联合收割机临床和教学活动与一个独立的实验室为基础的研究计划，重点是临床相关和转化研究。

DESCRIPTION (provided by applicant): The vast majority of T-cells are made in the thymus, a lymphoid organ that is particularly sensitive to radio- or chemotherapy. Strategies to enhance extrathymic T-cell development may therefore be useful to improve the outcome of conditions such as hematopoietic stem cell transplantation, cancer, immunosuppression or certain viral infections. I previously performed studies in mouse models of HSCT and malignancies demonstrating the feasibility and efficacy of adoptive cell therapy with ex vivo generated T cells (preT) to enhance T cell reconstitution. I found that adoptively transferred preT can be used as an "off-the-shelf" cell therapy and administered across MHC barriers to enhance thymic regeneration and T cell immunity. The main goal of this proposal is to develop strategies to enhance thymus independent T cell reconstitution in cancer patients, using tissue culture and tissue engineering based immunotherapeutic approaches. I propose to study the contribution of extrathymic sites to preT- derived T cell reconstitution, and to develop tissue constructs for T cell development ex vivo and in vivo using three-dimensional bioresorbable polymer scaffolds resembling extracellular matrix. Biodegradable polymers have the advantage that they can be used to fabricate micro or nanofibrous three-dimensional matrices for in vivo grafting, and they may be molecularly tailored to release bioactive agents resulting in highly effective localized drug delivery and control of cell growth and differentiation. T cell development will be studied in vitro and in vivo by implanting engineered stromal cell-polymer scaffold composites or cell-free thymic regeneration templates into mice followed by analysis of cell growth, differentiation, migration, and function (including anti-tumor activity). Characterization of host and biomaterial responses will also include analysis of vascularization of implants, biomaterial degradation, and inflammatory responses to implantation. Based on my preliminary data using an improved tissue engineering method with optimized design, biomaterial properties and cell-biomaterial interactions I expect that implantation of a tissue engineered artificial thymic microenvironment will result in enhanced T cell immunity and will contribute to tumor immunosurveillance. My goal over the next five years, with the help of this career development award, is to establish myself as a physician-scientist in the field of Pediatric Hematology/Oncology and to attain a tenure-track position at an academic center. As a physician-scientist, I hope to combine clinical and teaching activities with an independent laboratory-based research program with focus on clinically relevant and translational research.