Image-guided cancer therapy using heat activatable CAR T cells

摘要 嵌合抗原受体(CAR)T细胞正在改变血液系统恶性肿瘤的临床护理，刺激 为扩大其在不同癌症类型和应用中的应用做出了大量努力。然而，这种成功并没有 可靠地转化为实体肿瘤，包括乳腺癌。领养转让后，一小部分汽车 T细胞能够渗入肿瘤部位，肿瘤微环境(TME)具有高度的免疫抑制作用。 共同管理生物制品，以加强贩运或克服TME(例如，细胞因子或免疫检查) 点抑制剂)具有增强CAR T细胞活性的潜力。然而，它们同时影响汽车和内燃机- NOU T细胞群，这可能导致靶外杀伤、全身毒性和有限的治疗窗口。 此外，CAR T细胞渗透和贩运的非侵入性生物标志物需要在治疗早期进行评估。 部件响应。该建议旨在提高CAR T细胞疗法对抗固体的整体安全性和有效性 利用CAR T细胞，同时标记金纳米棒(AuNRs)和热工程 基因开关(TGSS)，通过1)证实AuNR-TGS-CAR T细胞在肿瘤部位的渗透 超声和光声(US/PA)成像系统；2)实现对局部免疫细胞的精确控制 US/PA引导下聚焦超声(FUS)激活和治疗TGS-CAR T细胞 和热(US/PA/TH)成像平台。TGS是一种在体内转录不活跃的基因结构 温度，但在40-42℃经历急剧的热转变，以触发转基因表达达到更高的水平 比基本水平高200倍以上。TGS允许热靶向肿瘤以激活浸润性CAR T细胞 在当地产生有效的治疗性基因，否则在全身给药时会有毒。这个 US/PA/TH成像平台将确认细胞渗透，通过无创标测引导FUS热量输送 肿瘤微环境中的局部温度，并量化治疗反应的关键生物标志物。这些 CAR T细胞工程和成像方面的协同进展将在HER2-CAR T细胞的背景下进行测试 对于大约30%的患者携带HER2基因和/或 HER2过度表达。影像引导的CAR T细胞治疗方法的临床前评估将按 在原位注射E0771肿瘤细胞的同基因乳腺癌模型中，表达- 将人HER2基因导入B6-HER2转基因小鼠。HER2-CAR T细胞将与控制TGS的TGS一起工程 刺激性细胞因子IL-15SA。成功完成我们的研究将产生一个新的类形象指导 CAR T细胞治疗，在限制全身毒性的同时，提高对乳腺肿瘤的反应。最新进展 通过这些研究开发的可扩展到其他CAR T细胞受体，以对抗其他类型的癌症。

ABSTRACT Chimeric antigen receptor (CAR) T cells are transforming clinical care for hematological malignancies, spurring numerous efforts to expand their use for different cancer types and applications. However, this success has not reliably translated to solid tumors, including breast cancer. Following adoptive transfer, a small fraction of CAR T cells manage to infiltrate tumor sites and the tumor microenvironment (TME) is highly immunosuppressive. Co-administration of biologics to enhance trafficking or to overcome the TME (e.g., cytokines or immune check- point inhibitors) have the potential to enhance CAR T cell activity. However, they affect both CAR and endoge- nous T cells populations, which can lead to off-target killing, systemic toxicities, and limited therapeutic windows. Moreover, noninvasive biomarkers of CAR T cell infiltration and trafficking are needed to assess early on treat- ment response. This proposal seeks to improve overall safety and efficacy of CAR T cell therapy against solid tumors by utilizing CAR T cells, simultaneously tagged with gold nanorods (AuNRs) and engineered with thermal gene switches (TGSs), by 1) confirming AuNR-TGS-CAR T cell infiltration at the tumor site using a combined ultrasound and photoacoustic (US/PA) imaging system, and 2) achieving precisely controlled local immune cell activation and therapy by mild heating of TGS-CAR T cells using focused ultrasound (FUS) guided by US/PA and thermal (US/PA/TH) imaging platform. TGS are genetic constructs that are transcriptionally inactive at body temperature but undergo a sharp thermal transition at 40–42°C to trigger transgene expression to levels greater than 200-fold above basal levels. TGS allows thermal targeting of tumors to activate infiltrated CAR T cells to locally produce potent therapeutic genes that would otherwise be toxic when administered systemically. The US/PA/TH imaging platform will confirm cell infiltration, guide FUS delivery of heat by noninvasive mapping of local temperatures within the tumor microenvironment, and quantify key biomarkers of therapy response. These synergistic advances in CAR T cell engineering and imaging will be tested in the context of HER2-CAR T cells for breast cancer where approximately 30 percent of patients carry an amplification of the HER2 gene and/or HER2 over-expression. Preclinical evaluation of the image-guided CAR T cell therapy approach will be per- formed in a syngeneic model of mammary adenocarcinoma by orthotopic injection of E0771 tumor cells express- ing human HER2 into B6-HER2 transgenic mice. HER2-CAR T cells will be engineered with TGS that control stimulatory cytokine IL-15SA. The successful completion of our studies will result in a new class of image-guided CAR T cell therapy to improve response against breast tumors while limiting systemic toxicity. The advances developed through these studies can be extended to other CAR T cell receptors against other cancer types.