Optimized ex vivo expansion of anti-tumor Th1 and Tc1 for adoptive immunotherapy

描述（由申请人提供）：最近的临床试验表明，晚期黑色素瘤可以用非清髓性化疗和自体过继性T细胞免疫疗法（AIT）联合治疗，以达到50%的临床应答率。然而，这种临床反应并不持久。在没有T细胞帮助（Th）的情况下，细胞毒性T细胞（CTL）的寿命很短，输注后的持续性有限。此外，在输注CD 8+占优势的肿瘤特异性T细胞系后产生抗原（Ag）阴性变体，表明肿瘤容易逃避集中治疗。我们的目标是通过提供具有功能特征的肿瘤Ag特异性CD 4 + Th 1细胞作为输注产品的核心成分，优化并扩展AIT至晚期乳腺癌。肿瘤抗原特异性CD 4 + Th 1细胞可归巢肿瘤并分泌炎性细胞因子，调节肿瘤微环境，增强局部抗原呈递细胞（APC）的功能。所得的内源性肿瘤细胞的加工增加导致表位扩散。通过提供稳健的CD 4 + Th 1免疫应答，将引发肿瘤Ag特异性CD 8 + T细胞，并且所产生的应答将是长期的。我们的目标是促进肿瘤特异性，表位扩散，Th 1型CD 4+反应作为有效AIT的重要组成部分。这种策略已经通过我们自己的HER-2/neu（HER 2）过表达乳腺癌III/IV期患者的疫苗试验得到验证。用MHC II类结合HER 2衍生肽疫苗接种的患者证明了显著的存活优势，如果他们不仅实现了对疫苗肽的增强的CD 4 + T细胞应答，而且还实现了对由他们的肿瘤表达但不存在于疫苗中的额外HER 2表位的T细胞应答。在动物研究中，我们观察到在T细胞培养期间包含自体树突状细胞（DC）可以显著提高再输注时的T细胞治疗性能。此外，适当活化的DC可以促进具有更高功能亲合力的T细胞的扩增，包括可以直接裂解MHC限制性肿瘤的CD 8+细胞溶解性T细胞。我们建议开发一种临床相关的方法来体外扩增HER 2特异性T细胞，使用在与待活化的T细胞相同的培养物中同时产生的最佳活化的自体DC。我们还将评估这些培养方法是否增加表位扩散。

DESCRIPTION (provided by applicant): Recent clinical trials have demonstrated that advanced melanoma can be treated with a combination of nonmyeloablative chemotherapy and autologous adoptive T cell immunotherapy (AIT) to achieve a 50% clinical response rate. Such clinical responses are not, however, consistently durable. Cytotoxic T cells (CTL) are shortlived in the absence of T cell help (Th), with limited persistence after infusion. Furthermore, antigen (Ag) negative variants develop after infusion of CD8+ predominant tumor specific T cell lines, suggesting tumors readily escape from focused therapy. Our goal is to optimize and extend AIT to advanced breast cancer by providing functionally characterized tumor Ag-specific CD4+ Th1 cells as a central component of the infused product. Tumor Ag-specific CD4+ Th1 cells can home to tumor and secrete inflammatory cytokines, modulating the microenvironment to enhance the function of local antigen presenting cells (APC). The resultant increased processing of endogenous tumor cells results in epitope spreading. By providing a robust CD4+ Th1 immune response, tumor Ag-specific CD8+ T cells will be elicited, and the response generated will be long lived. We aim to promote tumor-specific, epitope spreading, Th1-type CD4+ responses as an essential component of effective AIT. This strategy has been validated by our own vaccine trials for Stage III/IV patients with HER-2/neu (HER2)-overexpressing breast cancer. Patients vaccinated with MHC Class II-binding HER2-derived peptides evidenced a significant survival advantage if they achieved not only enhanced CD4+ T cell responses to vaccine peptides, but also T cell responses to additional HER2 epitopes expressed by their tumors but absent from the vaccine. In animal studies we observe that the inclusion of autologous dendritic cells (DCs) during T cell culture can markedly improve T cell therapeutic performance at the time of re-infusion. Moreover, appropriately activated DCs can promote the expansion of T cells with higher functional avidity, including CD8+ cytolytic T cells that can directly lyse MHC-restricted tumors. We propose to develop a clinically relevant method to expand HER2 specific T cells ex vivo, using optimally activated autologous DC generated simultaneously in the same cultures as the T cells to be activated. We will also assess whether these culture methods increase epitope spreading.