PO.IM01.08 · 免疫学
经纳米颗粒光热疗法改造的抗原特异性T细胞在免疫功能健全的卵巢癌小鼠模型中显示出抗肿瘤疗效
Antigen-specific T cells engineered with nanoparticle photothermal therapy demonstrate antitumor efficacy in an immunocompetent murine model of ovarian cancer
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
卵巢癌（OC）是最致命的妇科恶性肿瘤，对免疫检查点阻断的应答率不足10%。使用肿瘤裂解物冲击的树突状细胞进行个体化疫苗接种可放大T细胞应答，包括新表位特异性T细胞，但无法治愈。因此，放大预存的肿瘤特异性T细胞应答尚不充分。我们开发了一种新方法，利用普鲁士蓝纳米颗粒光热疗法（PBNP-PTT）在体外扩增针对OC特异性的T细胞，并使用同基因小鼠模型验证了其体内疗效。以PBNP-PTT生成的ID8 OC细胞裂解物刺激从健康雌性C57Bl6小鼠中分离的骨髓来源树突状细胞（BMDCs）。将自体脾脏CD3+ T细胞与BMDCs体外共培养，并使用IFNy ELISpot和MTS细胞毒性试验在体外评估肿瘤特异性激活与杀伤。携带ID8B OC细胞的同类系小鼠接受体外扩增的T细胞或非特异性扩增的T细胞，并对积聚的腹水进行细胞因子组成分析。通过光谱流式细胞术对过继转移的T细胞进行免疫表型分析。与非特异性扩增的T细胞相比，用经PBNP-PTT生成的OC细胞裂解物激发的DCs进行体外T细胞扩增，产生了一群CD8+ T细胞，其在肿瘤共培养中的IFNy和TNFa分泌增强。PBNP-PTT扩增的T细胞在效靶比递增时表现出更强的肿瘤细胞杀伤，且未表现出脱靶IFNy分泌。与接受非特异性T细胞的小鼠相比，接受OC扩增T细胞的荷瘤雌性C57Bl6小鼠存活显著延长，肿瘤负荷降低。用PBNP-PTT裂解物扩增的过继转移T细胞在体内也存活更久，并在腹水中维持激活状态，且与同期表观遗传治疗协同以进一步延长生存期。使用PBNP-PTT的体外扩增方法也应用于健康人类献血者，以生成在受到人类OC细胞系攻击时表现出强效激活的人类T细胞。总之，我们开发了一种利用纳米颗粒光热疗法在体外改造针对卵巢癌特异性T细胞的新方法。本研究首次利用PBNP-PTT在体外，使用卵巢癌自体小鼠模型证明了体内抗肿瘤活性。
查看英文原文 English abstract
Ovarian cancer (OC) is the most lethal gynecological malignancy with less than a 10% response rate to immune checkpoint blockade. Personalized vaccination with tumor lysate-pulsed dendritic cells amplifies T cell responses, including neoepitope-specific T cells, but is not curative. Thus, amplifying the pre-existing tumor-specific T cell response is insufficient. We developed a novel method to expand T cells ex vivo for OC specificity using Prussian Blue nanoparticle-photothermal therapy (PBNP-PTT), and verified in vivo efficacy using a syngeneic murine model. PBNP-PTT -generated ID8 OC cell lysate was used to stimulate bone marrow-derived dendritic cells (BMDCs) isolated from healthy female C57Bl6 mice. Autologous splenic CD3+ T cells were cocultured ex vivo with BMDCs and assessed in vitro for tumor-specific activation and killing using IFNy ELISpot and MTS cytotoxicity assays. Congenic mice bearing ID8B OC cells received either ex vivo expanded T cells or nonspecifically expanded T cells, and the accumulated ascites was profiled for cytokine composition. Adoptively transferred T cells were immunophenotyped with spectral flow cytometry.Ex vivo expansion of T cells with DCs primed using PBNP-PTT-generated OC cell lysate produced a pool of CD8+ T cells with enhanced IFNy and TNFa secretion in tumor coculture compared to nonspecifically expanded T cells. PBNP-PTT-expanded T cells exhibited greater tumor cell killing at increasing effector-to-target ratios and did not demonstrate off-target IFNy secretion. Tumor-bearing female C57Bl6 mice receiving OC-expanded T cells lived significantly longer and exhibited decreased tumor burden compared to mice receiving nonspecific T cells. Adoptively transferred T cells expanded with PBNP-PTT lysate also persisted longer in vivo with maintained activation in the ascites, and synergized with concurrent epigenetic therapy to further prolong survival. Ex vivo expansion methods using PBNP-PTT were also applied to healthy human blood donors to generate human T cells that demonstrate potent activation when challenged with human OC cell lines. In summary, we developed a novel method of engineering T cells ex vivo for specificity against ovarian cancer using nanoparticle photothermal therapy. This study is the first to harness PBNP-PTT ex vivo to demonstrate antitumor activity in vivo using an autologous mouse model of ovarian cancer.
利益披露 Disclosure
A. V. Lee, None..
E. Grundy, None..
J. Colina, None..
E. Sweeney, None..
R. Fernandes, None..
N. Muniraj, None..
R. Y. Cruz, None..
K. B. Chiappinelli, None.