Supplemental Digital Content is available in the text. Preeclampsia is a potentially life-threatening multisystem disease affecting 4% to 8% of pregnant women after the 20th week of gestation. An excess of placental expressed antiangiogenic soluble VEGF (vascular endothelial growth factor)-receptor 1 (soluble FMS-like tyrosine kinase 1) scavenges VEGF and PlGF (placental growth factor), causing generalized endothelial dysfunction. Interventions to restore the angiogenic balance in preeclamptic pregnancies are intensively studied and improve maternal and neonatal outcomes. Especially extracorporeal strategies to remove sFlt-1 are promising in human pregnancy. However, available apheresis systems adsorb sFlt-1 unspecifically and with low efficiency. Affinity-enhanced ligands are needed to improve performance and compatibility of apheresis treatments. Using computerized molecular modeling, we developed multimeric VEGF molecules comprised of single-chain VEGF165 dimers (scVEGF165). A short peptide linker hampers intrachain dimerization to induce assembly preferably as tetrameric molecules as visualized in negative staining electron microscopy. scVEGF165 multimers possess 1.2-fold higher affinity for sFlt-1 as compared to the available antibodies or monomeric VEGF. Consequently, scVEGF multimers have the ability to competitively release sFlt-1 bound PlGF and, in particular, VEGF. In ex vivo adsorption experiments using serum samples from patients with preeclampsia, scVEGF multimers reduce sFlt-1 levels by 85% and increase PlGF and VEGF levels by 20- and 9-fold, respectively. Finally, performance and stability of sFlt-1 capturing scVEGF165 multimers were scrutinized on different matrices of which biocompatible agarose matrix yielded optimal results. We introduce the first VEGF-based highly efficient sFlt-1 apheresis system that is directly applicable in vivo due to utilization of inert agarose matrix, using a homomultimeric form of VEGF165 to restore the angiogenic balance in preeclampsia.

中文翻译：

---

亲和力增强的多聚体 VEGF（血管内皮生长因子）和 PlGF（胎盘生长因子）变体用于特异性吸附 sFlt-1 以恢复先兆子痫的血管生成平衡

补充数字内容在文本中可用。先兆子痫是一种可能危及生命的多系统疾病，在妊娠 20 周后影响 4% 至 8% 的孕妇。过量的胎盘表达的抗血管生成可溶性 VEGF（血管内皮生长因子）受体 1（可溶性 FMS 样酪氨酸激酶 1）清除 VEGF 和 PlGF（胎盘生长因子），导致全身内皮功能障碍。对恢复先兆子痫妊娠血管生成平衡的干预措施进行了深入研究，以改善孕产妇和新生儿的结局。特别是去除 sFlt-1 的体外策略在人类怀孕中很有希望。然而，可用的单采系统非特异性吸附 sFlt-1，效率低下。需要亲和力增强的配体来提高单采治疗的性能和相容性。使用计算机分子模型，我们开发了由单链 VEGF165 二聚体 (scVEGF165) 组成的多聚 VEGF 分子。短肽接头阻碍链内二聚化以诱导组装，优选作为四聚体分子，如负染色电子显微镜中所见。与可用的抗体或单体 VEGF 相比，scVEGF165 多聚体对 sFlt-1 的亲和力高 1.2 倍。因此，scVEGF 多聚体能够竞争性地释放 sFlt-1 结合的 PlGF，尤其是 VEGF。在使用先兆子痫患者血清样本的体外吸附实验中，scVEGF 多聚体将 sFlt-1 水平降低了 85%，并使 PlGF 和 VEGF 水平分别增加了 20 和 9 倍。最后，sFlt-1 捕获 scVEGF165 多聚体的性能和稳定性在不同基质上进行了仔细检查，其中生物相容性琼脂糖基质产生了最佳结果。我们介绍了第一个基于 VEGF 的高效 sFlt-1 单采系统，由于利用惰性琼脂糖基质，该系统可直接应用于体内，使用同型多聚体形式的 VEGF165 来恢复先兆子痫的血管生成平衡。