小动脉血栓磁共振免疫成像的实验研究

The experimental study of MRI immune imaging in arterioles thrombosis

目的探讨Gd-DTPA-D-二聚体抗体的MR靶向免疫成像显示小动脉血栓的可行性。方法以DTPA连接Gd和D-二聚体抗体制备血栓MR靶向对比剂,综合多种方法制作大鼠右侧股动脉血栓模型。实验组大鼠注射Gd-DTPA-D-二聚体抗体,对照组大鼠注射等量的Gd-DTPA,均分别于注射前及注射后5、10、30和60min进行MR扫描,测量血栓信号变化情况。取5只未注射MR对比剂的大鼠模型,注射99mTc-DTPA-D-二聚体抗体,分别于注射前及注射后5、10、30和60min处死,取出血栓、心、肝、脾、肺、肾和血液,分析抗体在体内的分布。结果观察到注射Gd-DTPA-D-二聚体抗体组与注射Gd-DTPA组在不同时间点之间的差异有统计学意义(F=7.195,P=0.044;F=6.318,P=0.003),实验组在10min点上血栓信号强度比(SNR)的均数最高,这与MR图像在10min的点显像最佳相符,体内放射免疫技术测定显示血栓部位聚集的99mTc-DTPA-D-二聚体抗体高于血液本底,因此是特异性聚集。结论 Gd-DTPA-D-二聚体抗体的MR靶向免疫成像对于显示小动脉血栓可能具有良好的应用前景。

Objective To investigate the feasibility of MR targeting immunoimaging using Gd-DTPA-D-dimer antibody to show the arterioles thrombosis.Methods Connecting cDTPA with the Gd and D-dimer antibody to prepare MRI contrast agent targeting the thrombosis and make the rat model of femoral arterial thrombosis integrating a number of ways.The rats were randomized into 2 groups that received injection of either Gd-DTPA-D-dimer antibody through the tail vein,or Gd-DTPA.All rats received MRI examination before injection and at 5,10,30,and 60?min post-injection to measured the changes of thrombus signals.Another 5 rat models were executed before injected with 99mTc-DTPA-D-dimer antibody and at 5,10,30 and 60 min post-injection to taking out the thrombosis,heart,liver,spleen,lung,kidney and blood,and the distribution of antibody in the body was analyzed.Results The difference between the two groups had statistical difference among the different time(?F?=?7.195,P?=?0.044;F?=?6.318,P?=?0.003?).Rats that received Gd-DTPA-D-dimer antibody had the maximum means of the signal intensity ratio of the thrombus which were consistent with the best MR imaging on 10 min.The radioimmunoassay showed that thrombosis parts gathered 99mTc-DTPA-D-dimer antibody were specific aggregation.Conclusion MR targeting immunoimaging using Gd-DTPA-D-dimer antibody for displaying arterioles thrombosis may have a good application prospect.