PO.CL05.02 · 临床研究
磷酸化IRF7增强GPC3靶向CAR T细胞在实体瘤中的抗肿瘤活性
Phosphorylated IRF7 enhances antitumor activity of GPC3-targeted CAR T cells in solid tumors
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
磷脂酰肌醇蛋白聚糖3（GPC3）在肝细胞癌（HCC）和肝母细胞瘤（HBL）中高表达，但在健康成熟组织中不表达，因此是一个有前景的免疫治疗靶点。在近期一项研究中，GPC3-CAR或共表达IL15的GPC3-CAR T细胞（15.CAR）在患者中是安全的，IL15共表达显著增强了CAR T细胞扩增，实现了66%的疾病控制率和33%的抗肿瘤应答率。为阐明与治疗应答相关的分子程序，研究者对肿瘤浸润性CAR T细胞进行了单细胞RNA测序，并鉴定出与抗肿瘤应答相关的独特转录组差异，包括SWI/SNF下调以及FOS/JUN和I型干扰素家族成员上调。转录因子基序富集分析确定干扰素调节因子7（IRF7）为应答者中上调基因的主导转录驱动因子。我们假设IRF7将增强抗肿瘤活性，本研究考察了野生型和组成型活性IRF7表达在GPC3-CAR T细胞中的作用（分别为IRF7.CAR和pIRF7.CAR）。与15.CAR T细胞相比，IRF7.CAR和pIRF7.CAR T细胞在基线（制造后）经流式细胞术检测显示出显著更高的初始型（CD45RA+ CCR7+ CD62L+；CD4 p=0.0348；CD8 p=0.0163）、中央记忆型（CM，CD45RO+ CCR7+ CD62L+；CD4 p=0.0382）、LAG3+（CD4 p=0.0236，CD8 p=0.0030）细胞群，以及显著更低的效应记忆型（TEM，CD45RA- CCR7- CD62L-；CD4 p=0.0221）细胞群。在使用IncuCyte系统的重复肿瘤攻击实验中，IRF7.CAR和pIRF7.CAR T细胞具有更高的扩增能力和显著改善的杀伤效力（p<0.001）。最后，在体内，pIRF7GPC3+细胞在荷HCC和HBL异种移植瘤的NSG-MHC I/II双敲除小鼠中，无论在高剂量（5x10^6）还是低剂量（3x10^6）条件下均显示出更快速的肿瘤清除。这些发现表明pIRF7增强了CAR T细胞功能。将pIRF7整合入GPC3靶向CAR代表了一种改善实体瘤疗效的新策略。
查看英文原文 English abstract
Glypican-3 (GPC3) is highly expressed in hepatocellular carcinoma (HCC) and hepatoblastoma (HBL), but not in healthy mature tissues; thus, represents a promising immunotherapeutic target. In a recent study, GPC3-CAR or IL15 co-expressing GPC3-CAR T cells (15.CAR) were safe in patients, IL15 co-expression significantly enhanced CAR T cell expansion and resulted in a disease control rate of 66% and antitumor response rate of 33%. To elucidate molecular programs associated with therapeutic response, single cell RNA sequencing of tumor infiltrating CAR T cells was performed and unique transcriptomic profile differences were identified associated with antitumor responses including downregulation of SWI/SNF and upregulation of FOS/JUN and Type I Interferon family members. Transcription factor motif enrichment analyses identified Interferon regulatory factor 7 (IRF7) as the dominant transcriptional driver of genes upregulated in responders. We hypothesized that IRF7 will boost the antitumor activity and this study examined the role of wild type and constitutively active IRF7 expression in GPC3-CAR T cells (IRF7.CAR and pIRF7.CAR, respectively).Compared with 15.CAR T cells, IRF7.CAR and pIRF7.CAR T cells showed significantly higher naïve (CD45RA+ CCR7+ CD62L+; CD4 p=0.0348; in CD8 p=0.0163; ), Central memory (CM, CD45RO+ CCR7+ CD62L+; CD4 p= 0.0382), LAG3+ (CD4 p=0.0236, CD8 p=0.0030) and significantly lower effector memory (TEM, CD45RA- CCR7- CD62L-; CD4 p= 0.0221) cell population at baseline, post-manufacturing based on flow cytometry. IRF7.CAR and pIRF7.CAR T cells had higher expansion and significantly improved killing efficacy (p<0.001) in repeated tumor-challenge assays using the IncuCyte system. Finally, In vivo, pIRF7GPC3+ cells showed more rapid tumor clearance under both high (5x10^6)- and low-dose (3x10^6) conditions in NSG-MHC I/II double knockout mice bearing HCC and HBL xenografts. These findings demonstrate that pIRF7 enhances CAR T-cell function. Incorporation of pIRF7 into GPC3-targeted CARs represents a novel strategy to improve efficacy against solid tumors.
利益披露 Disclosure
I. Cevher Zeytin, None..
C. Li, None..
D. de la Cerda, None..
L. Caraballo Galva, None.
A. Heczey,
Waypoint Bio Consultant.
CARGO Therapeutics Scientific Advisory Board.