Defining a novel role for B cells in imprinting CD8 T cells with potent antitumor activity

项目摘要 使用肿瘤浸润性T淋巴细胞（TIL）对癌症患者进行的连续性细胞转移（ACT）疗法已经 未能充分发挥其潜力，主要是由于耗尽，短寿命的CD 8 + T细胞的转移。最近我们 发现T细胞适应性可以通过用Toll样受体9激活TIL培养物中的B细胞来改善 (TLR)激动剂CpG。理解和操纵维持T细胞持久性的TLR通路将 有可能开启对肿瘤的持久反应。此外，关于B和CD 8 + T细胞如何相互作用的研究很少 促进T细胞肿瘤免疫。在这个提议中，我们试图阐明T细胞 从CpG处理的培养物中产生的，能够在体内消除已建立的肿瘤而不需要IL-2或 疫苗接种。我们的初步数据显示，用CpG处理的B细胞具有明显的CD 40（共刺激性）。 蛋白），同时CD 8 + T细胞表达CD 40 L。我们发现此时CD 8 + T细胞获得T细胞 由CXCR 5、ICOS和PD-1表达表示的滤泡记忆样（TFML）表型。我们将CD 40 CpG处理后B细胞中的信号传导负责CD 8 + TFML细胞的发育并增强 抗肿瘤活性。由CpG处理的培养物产生的CD 8 + T细胞获得由高表达的独特表型。 IL-2细胞因子受体IL-2 R β的表达和CD 39 β的暗淡表达我的共同导师Mark Rubinstein博士 最近发表了IL-2 R β在ACT模型中促进T细胞植入的重要性。 相反，与载体处理的T细胞相比，在CpG产生的T细胞上仅最低限度表达的CD 39， 细胞，是与病毒和癌症模型中“终末耗竭”的CD 8 + T细胞相关的标志物。因此，我寻求 研究CpG如何诱导这种有效的细胞产物的机制以及IL-2 R β和CD 39的作用 实现强大的抗肿瘤反应。总的来说，我假设TLR 9激动剂CpG在一个细胞周期中激活了B细胞。 抗肿瘤T细胞培养，通过B细胞中的CD 40信号传导促进T细胞被印上TFML表型。我 我将在目标1中考察这个想法。此外，我认为IL-2 R β和CD 39，由TLR 9信号负调控， 负责增强过继转移的CD 8 + T细胞的抗肿瘤特性。这个概念将 在目标2中分析。揭示B细胞如何被CpG激活成为有效的抗原呈递细胞 Aim 1中的CD 8 + T细胞转化为CD 8 + T细胞将为Toll样受体激动剂的癌症治疗建立新的范例 CpG此外，这些研究的结果将为具有强免疫功能的T细胞的产生提供深入了解。 记忆肿瘤，并将有重要的临床意义的癌症患者。总体而言，拟议 预期研究将证明用CpG激活TLR 9通路可充分诱导 对晚期肿瘤的生长和复发具有持久的免疫力。

Project Summary Adoptive cell transfer (ACT) therapies using tumor infiltrating T lymphocytes (TIL) for cancer patients have failed to fulfill their full potential, mostly due to the transfer of exhausted, short-lived CD8+ T cells. Recently, we discovered that T cell fitness can be improved by activating B cells in a TIL culture with the Toll-like receptor 9 (TLR) agonist CpG. Understanding and manipulating the TLR pathways that sustain T cell persistence will potentially unlock durable responses to tumors. Further, there is little research on how B and CD8+ T cells interact to promote T cell tumor immunity. In this proposal we seek to elucidate the mechanism by which T cells generated from a CpG-treated culture, are able to abolish established tumors in vivo without the need of IL-2 or vaccine administration. Our preliminary data shows B cells treated with CpG have overt CD40 (costimulatory protein) and concomitantly CD8+ T cells express CD40L. We found that at this time CD8+ T cells acquire a T follicular memory-like (TFML) phenotype denoted by CXCR5, ICOS, and PD-1 expression. We posit that CD40 signaling in B cells post CpG-treatment is responsible for the development of CD8+ TFML cells and potentiated antitumor activity. CD8+ T cells generated from CpG-treated cultures gain a unique phenotype denoted by high expression of the IL-2 cytokine receptor IL-2R and dim expression of CD39 My co-mentor Dr. Mark Rubinstein recently published the importance of the IL-2R in promoting engraftment of T cells in an ACT model. Conversely, CD39 which is only minimally expressed on CpG-generated T cells compared to vehicle treated T cells, is a marker associated with “terminally exhausted” CD8+ T cells in viral and cancer models. Thus, I seek to study the mechanisms underlying how CpG induces this potent cell product and the roles of IL-2R and CD39 in achieving robust antitumor responses. Overall, I hypothesize that TLR9 agonist CpG activates B cells in an antitumor T cell culture, promoting T cells to be imprinted with a TFML phenotype via CD40 signaling in B cells. I will examine this idea in Aim 1. Moreover, I posit that IL-2R and CD39, inversely regulated by TLR9 signaling, are responsible for augmenting the antitumor properties of adoptively transferred CD8+ T cells. This concept will be analyzed in Aim 2. Uncovering how B cells can be activated by CpG to become potent antigen presenting cells to CD8+ T cells in Aim 1 will establish a new paradigm for cancer therapy with Toll-like receptor agonist CpG. Also, findings from these studies will provide insight into the generation of T cells with strong immunological memory to tumors and will have important clinical implications for patients with cancer. Overall, the proposed research is expected to demonstrate that activation of the TLR9 pathway with CpG may sufficiently induce durable immunity against the growth and recurrence of advanced tumors.