Establishment of a mouse model for the induction of preeclampsia by soluble VEGFR-1/flt-1 and its modulation by exogenous treatment with antibodies and receptor ligands

在过去的24个月里，我们的工作假设是VEGF-A和PIGF必须得到很好的调节，sFlt-1和VEGF/PIGF水平之间的组织内平衡似乎对维持血管内稳态起着至关重要的作用，这种平衡的失调与几种血管疾病有关。这种从胎盘分泌到母体血液中的sFlt-1水平的增加与游离VEGF-A和PIGF的循环水平的降低相关，并导致体内内皮功能障碍。在最后一个阶段，我们成功地建立了一个小鼠模型，先兆子痫使用腺病毒过表达的sFlt-1在Balb/c小鼠。这是通过将2.5-5 × 108个病毒颗粒静脉注射到8-11周龄动物的尾静脉中来实现的。8-10天后，处死动物，并通过组织化学分析来分析肾脏的肾小球。可溶性flt-1过表达导致肾小球微血管管腔的强烈缩小所示的微血管和管的塌陷。腺病毒的注射也导致病毒处理的动物的肝脏体积的大量增加，表明大部分注射的病毒颗粒位于肝脏中。到目前为止，尚未详细研究血压和蛋白尿等参数。为了调节肾脏中的病理效应，我们已经开始通过噬菌体展示开发阻断抗体。因为这是项目的高风险部分，我们能够从一个合作小组招募flt-1的阻断抗体。sflt-1对肾功能不全的诱导作用将在最后一个阶段详细分析。为此，我们也将开始合作，通过遥测测量高血压的诱导，并希望调查我们的问题，如果阻断抗体flt-1可以调节实验诱导的小鼠先兆子痫的影响。

Our work hypothesis during the last 24 months was that VEGF-A together with PIGF must be very well regulated and that intratissual balance between sFlt-1 and VEGF/PIGF levels seems to play a crucial role for maintaining vascular homeostasis and that dysregulation of this balance is involved in several vascular diseases. This increasing levels of sFlt-1 secreted from placenta into the maternal blood are associated with decreasing circulating levels of free VEGF-A and PIGF and results in endothelial dysfunction in vivo. In the last period we have sucessfully established a mouse model for preeclampsia using adenoviral overexpression for sFlt-1 in Balb/c mice. This was achieved by intravenous injection of 2.5-5 x108 virus particles into the tail vein of 8-11 week old animals. After 8-10 days animals were sacrified and the glomeruli of the kidney were analyzed by histochemical analysis. Soluble flt-1 overexpression leads to a collapse of microvessels and tubes indicated by a strong reduction of microvessel lumen in a glomerulus. Injection of adenovirus also lead to a massive increase in liver volumen of virus treated animals, indicating that most of the injected virus particles were localized in the liver. So far parameter like blood pressure and proteinuria were not investigated in detail. In order to modulate the pathological effect in the kidney we have started to develop blocking antibodies by phage-display. Because this is a high risk part of the project, we were able to recrute blocking antibodies for flt-1 from a collaborating group. The sflt-1 effect induced for kidney dysfunction will now be analyzed in the last period in great detail. For this purpose we will also start a collaboration to measure induction of high blood pressure by telemetry and want to investigate our question, if blocking antibody to flt-1 can modulate the effect of preeclampsia experimentally induced in mice.