重定向人抗生物素蛋白修饰的CAR-T细胞过继免疫治疗表达EGFRvIII胶质瘤及其通过活体...

Retargeted human avidin-CAR T cells for adoptive immunotherapy of EGFRvIII expressing gliomas and their evaluation via optical imaging

Abstract
There has been significant progress in the design of chimeric antigen receptors (CAR) for adoptive immunotherapy targeting tumor-associated antigens. However, the challenge of monitoring the therapy in real time has been continually ignored. To address this issue, we developed optical molecular imaging approaches to evaluate a recently reported novel CAR strategy for adoptive immunotherapy against glioma xenografts expressing EGFRvIII. We initially biotinylated a novel anti-EGFRvIII monoclonal antibody (biotin-4G1) to pre-target EGFRvIII+ gliomas and then redirect activated avidin-CAR expressing T cells against the pre-targeted biotin-4G1. By optical imaging study and bio-distribution analysis, we confirmed the specificity of pre-target and target and determined the optimal time for T cells adoptive transfer in vivo. The results showed this therapeutic strategy offered efficient therapy effect to EGFRvIII+ glioma-bearing mice and implied that optical imaging is a highly useful tool in aiding in the instruction of clinical CAR-T cells adoptive transfer in future.

Keywords: adoptive immunotherapy, avidin-CAR, biotinylated, EGFRvIII, optical imaging
重定向人抗生物素蛋白修饰的CAR-T细胞过继免疫治疗表达EGFRvIII的胶质瘤及其通过活体成像的评估

摘要: 嵌合抗原受体（CAR）用于肿瘤相关抗原免疫治疗的设计已经取得了显著的进展。然而，一直忽视了实时监测治疗这一方面的挑战。为了解决这个问题，我们开发了一种光学分子成像来评估一个最近报道的新CAR-T治疗方案——过继免疫治疗表达EGFRvIII的胶质瘤。我们最初装备了一种新型的抗EGFR单克隆抗体（biotin-4g1），预靶向EGFRvIII 阳性的胶质瘤，然后用重定向活化的人抗生素蛋白修饰的CAR-T细胞来对抗预先靶向的生物素-4G1。通过光学成像研究和生物分布分析，证实了预靶和靶点的特异性，并确定了T细胞在体内过继治疗的最佳时机。结果表明这个治疗策略在EGFRvIII阳性的胶质瘤小鼠体内有良好的效果，也预示了光学成像是协助临床CAR-T细胞过继移植在未来教学中的一个非常有用的工具。
关键词：过继免疫治疗，抗生物素蛋白-CAR，生物素，EGFRvIII，光学成像