TEM-1抗体片段-近红外光分子探针在黑素瘤靶向诊断及实时手术导航中的应用研究

It’s been reported that in the pathological state, transmembrane protein TEM-1 dynamically participated in the vascular remodeling, thus promoting tumor growth. The pilot studyin our lab found that TEM-1 expression is increased in melanoma than in normal skin and it’s mainly expressed in tumor vascular endothelium or perivascular tissue. We previously synthesized TEM-1 specific human antibody fragment scFv78 and its derivatives such as 78F(ab')2 by genetic engineering. In this project, we try to prepare the specific molecular imaging probe IRDye.800CW-78F(ab')2 by targeting TEM-1 in the melanoma and analyze its biological and pharmacokinetics characteristics. In vitro and in vivo experiments are used to detect specific binding of IRDye 800CW-78F(ab')2 in melanoma, observing its effect in the border tracing of primary, metastases tumor and sentinel lymph nodes of melanoma, defining its high-resolution potential and effect on assisting surgery to improve tumor resection rate. This project will provide new ideas and methods for melanoma targeted diagnosis and treatment from a new perspective of molecules, cells, tissues, animals and the whole bio-system.

研究表明跨膜蛋白TEM-1在病理状态下动态参与血管重塑，促进肿瘤生长。申请人前期发现黑素瘤患者肿瘤组织中TEM-1较正常皮肤表达增高，且主要表达于肿瘤血管内皮及血管周围组织。前期用基因工程的方法合成了TEM-1特异性的全人抗体片段scFv78及其衍生物如78F(ab')2。据此提出黑素瘤微环境中，以TEM-1为切入点，制备特异性分子成像探针IRDye800CW-78F(ab')2，分析其生物及药物动力学特征；通过细胞和动物模型，体、内外检测IRDye800CW-78F(ab')2在黑素瘤中对TEM-1的特异性靶向结合；近红外光成像系统下，观察IRDye800CW-78F(ab')2对黑素瘤原发灶、转移灶及前哨淋巴结的示踪分辨潜能及其对辅助外科手术、提高肿瘤切除率的影响。从分子、细胞、组织、动物及整体水平，拟以一个新的视角为黑素瘤的精准靶向诊断和治疗提供新的思路和方法。

基于抗体的光分子影像技术近年来持续发展，让医生在手术期间对患者的肿瘤组织进行实时、高分辨率的特异性示踪成为可能，进而实现辅助病灶精准定位及病灶切除。研究表明跨膜蛋白TEM-1在病理状态下动态参与血管重塑，促进肿瘤生长。申请人前期发现黑素瘤患者肿瘤组织中TEM-1较正常皮肤表达增高，且主要表达于肿瘤血管内皮及血管周围组织。本研究前期合成了TEM-1特异性的全人抗体片段scFv78及其衍生物78F(ab')2。项目开展后在此基础上，制备了特异性荧光标记的抗体片段分子探针VivoTag-S750-78F(ab’)2 并对其进行特征分析，体外实验检测了该探针的抗原-抗体结合亲和力。进一步建立了相关黑素瘤及其他肿瘤小鼠模型，在体内实验中，用近红外光成像系统检测该探针对体内肿瘤TEM-1的特异性靶向结合，验证了该分子探针在活体动物中靶向TEM-1（+）肿瘤的能力，研究了近红外光成像系统下该分子探针对肿瘤示踪分辨潜能及其对辅助外科手术、提高肿瘤切除率的影响。从分子、细胞、组织、动物及整体水平，拟以一个新的视角为黑素瘤的精准靶向诊断和治疗提供新的思路和方法。