人工抗原提呈细胞膜纳米载药系统的构建及其联合CRISPR-Cas9技术介导PD-1敲除的T细胞免疫疗法在胃癌中的评价

Immunotherapy is currently one of the most promising therapeutic methods for tumor treatment. Based on our previous studies about drug delivery system, which were supported by the National Natural Science Foundation of China, this program is aimed at the preparation of artificial antigen presenting cell membrane-based drug delivery system by the involvement of a dual-targets and tumor penetrating fusion protein and a tumor antigen. So the ideal anti-tumor efficacy is under the premise that nanoparticles could not only accumulate in the tumor, penetrate into the center of the tumor, but also deliver tumor antigen into the tumor sites, activate immune responses. This study is focusing on the targeting effect, high penetration, as well as the immune responses, and safety of the system. Combining CRISPR-Cas9 mediated disruption of PD-1 on human T-cells, the anti-tumor efficacy is also evaluated. We believe that our research will provide scientific evidence to develop new targeted drug carriers and transit them to clinical application.

免疫治疗是目前肿瘤治疗最有发展前景的治疗策略之一。申请人所在的团队在前期国家自然科学基金赞助纳米载药系统的研究基础上，采用生物安全度高、保留原细胞功能的人工抗原提呈细胞膜，以最新自主研制的具有双特异靶向性、高穿透性融合蛋白anti-EGFR-iRGD和肿瘤抗原肽为依据，构建具有双靶向性、高穿透性、靶向运送抗原的人工抗原提呈细胞膜载药系统，研究其靶向能力、穿透能力、运送抗原肽能力及局部激活淋巴细胞能力。联合CRISPR-Cas9技术介导PD-1敲除的T细胞免疫疗法，评价其抗肿瘤作用及安全性。明确其作为一种新型的靶向载体在胃癌治疗中的价值，为临床应用提供科学依据。

免疫治疗是目前肿瘤治疗最有发展前景的治疗策略之一。申请人所在的团队在前期国家自然科学基金赞助纳米载药系统的研究基础上，采用生物安全度高、保留原细胞功能的淋巴细胞膜，以最新自主研制的具有双特异靶向性、高穿透性融合蛋白anti-EGFR-iRGD和肿瘤抗原肽为依据，构建具有双靶向性、高穿透性、靶向运送抗原的淋巴细胞膜载药系统，研究其靶向能力、穿透能力、运送抗原肽能力及局部激活淋巴细胞能力。联合CRISPR-Cas9技术介导PD-1敲除的T细胞免疫疗法，评价其抗肿瘤作用及安全性。明确其作为一种新型的靶向载体在胃癌治疗中的价值，为临床应用提供科学依据。申请人完成了构建了粒径大小均一、分散性好、载药量、包封率、稳定性达标的靶向纳米化生物膜载药系统。研究结果表明嵌插anti-EGFR-iRGD的纳米载药系统在荷瘤裸鼠体内具有明显的肿瘤靶向性、肿瘤组织穿透性及抗肿瘤作用，相比其他对照组有统计学差异。在研究的过程中，申请人发现将双靶向、高穿透性融合蛋白连接于T淋巴细胞表面不影响细胞的生长增殖、活力、表型及功能。在体外3D细胞球模型中，anti-EGFR-iRGD修饰的T细胞可有效穿透至肿瘤细胞球中心并抑制其增殖生长。在胃癌皮下瘤模型中，anti-EGFR-iRGD修饰的T细胞可浸润至肿瘤深部，荧光信号较对照T细胞组明显升高。iRGD修饰的T细胞与CRISPR-CAS9介导的PD-1敲除T细胞具有协同抗肿瘤作用，后续申请人将继续进行anti-EGFR-iRGD修饰的T细胞与CRISPR-CAS9介导的PD-1敲除T细胞的协同抗肿瘤作用评价。将靶向分子修饰在PD-1敲除的T淋巴细胞表面，可显著增强其体内抗肿瘤作用，具有较好的临床应用潜力，为肿瘤过继细胞免疫治疗提供了新的治疗策略和手段。