亲和素-生物素系统介导的炎症预定位显像研究

目的：探讨亲和素-生物素系统在小鼠炎症模型中进行预定位炎症显像的实验研究。方法：实验动物均为用肌肉注射松节油所致炎症模型,采用生物素化人免疫球蛋白（B-hIgG）和99mTc标记亲和素（99mTc-Avi-din）进行二步法预定位炎症显像,在注药后3h、6h、12h对小鼠炎症模型进行显像和体内生物学分布测定,并以^99mTc-hIgG和^99mTc-Avidin作为对照组。结果：二步法预定位显像组炎症病灶在3h即可显像,其靶/非靶（T/NT）比值为1.95,6h达3.12,血中放射性清除较快。而^99mTc-hIgG组T/NT在3h仅0.38,由于其分子量较大,血中清除时间较长,血本底较高,6h-12h血中仍保持较高放射性水平,且肝脏积聚放射性较多,图像也不清晰;^99mTc-Avidin组则在肝、肾有较多放射性浓聚。结论：二步法预定位炎症显像的T/NT比值较^99mTc直接标记hIgG法为高,且病灶显像时间提前,并可提高图像的清晰度。

Study on Pretargeting of Inflammation-Site and Imaging with Avidin-Biotin System

Objective To evaluate the feasibility of pretargeting of inflammation-site and imaging with avidin-bioltin system in mouse model.Methods A mouse inflammation model was established with intramuscular administration of turpentine.A two-step method of imaging was developed: biotinylated hIgG was first injected i.v.followed by 99mTc-Avidin intra-peritoneally 48h later.99mTc-hIgG or 99mTc-Avidin only intraperitoneally were used as controls.Imaging scintigraphy was performed and biodistribution was studied at 3,6...