彩色编码参数量化技术结合靶向微泡造影剂评价干细胞移植后微血管新生

Evaluation of angiogenesis after stem cell transplantation using color-encoded parametric quantification with targeted microbubbles in rabbits with myocardial infarction

目的探讨彩色编码参数量化（parametric quantification，PQ）技术结合靶向造影剂评价干细胞移植治疗兔急性心肌梗死（AMI）的微血管新生效应。方法制备携CD34单克隆抗体靶向微泡超声造影剂。新西兰大白兔80只，分别于AMI前、AMI后3d、干细胞移植术后4周进行心肌超声造影（MCE），采用PQ技术对比各组干细胞移植前后梗死区域色差评分及心肌灌注参数（A、β和A×β）。移植4周后行CD34抗体免疫组化检测微血管密度（MVD）。结果普通造影剂组（T＋C组）及靶向造影剂组（T＋T组）干细胞移植后各心肌节段的PI色差评分（P〈0．05）及A、β和A×β值（P〈0．01）均较本组内移植前改善。实验组干细胞移植后MVD均较对照组增加（P〈0．01），T＋T组增加最为明显（P〈0．05）。T＋C组A×β值与MVD具有相关性（r=0．658，P〈0．05），T＋T组β和A×β与MVD具有相关性（r=0．620，0．859，P均〈0．05），A×β（X）与MVD（Y）建立回归方程y=-130．986＋34．505X（R^2=0．556，P〈0．05）。结论PQ技术结合靶向微泡造影剂对无创评价干细胞移植后微血管新生具有一定的价值。

Objective To investigate the application of parametric quantification （PQ） with targeted microbubbles on angiogenesis after stem ceil transplantation in rabbits with myocardial infarction. Methods A CD34-targeted microbubble was prepared. Acute myocardial infarction （AMI） model were established by ligating coronary artery in 80 New Zealand white rabbits. Rabbits in common microbubble group （T ＋ C group） and CD34 targeted microbubble group （T ＋ T group） were subjected to myocardial contrast echoeardiography（MCE） ,then compare myocardial perfusion parameters （A,β and A ×βvalues） pre- and 3d postligation and 4 weeks after stem cell transplantation. Microvessel density （MVD） were determine by CD34 antibody immunohistochemistry. Results Compared to before stem ceil transplantation,the perfusion scores （ P 〈0.05） and A,β and A ×β values（ P %0.01） of T ＋ C group and T ＋ T group were increased than before transplantation and control group. MVDs after stem cell transplantation in experimental groups were higher than those of control group （ P 〈0.01 ）, especially the T ＋ T group. A ×β value in the T ＋ C group was correlated with MVD （ r = 0. 658, P 〈 0.05） ; β and A×β value in the T ＋ T group were correlated with MVD （r =0.620,0.859, P〈0.05）. A×β value （X） and MVD （Y） were included to establish the following regression equation： Y = - 130. 986 ＋ 34. 505 X （ R ^2 = 0. 556, P 〈 0.05）. Conclusions PQ and CD34 targeted microbubble probably provides some value in invasive evaluation of angiogenesis after stem cell transplantation.