Hanson Marina M, Liu Fengming, Dai Shen, Kearns Alison, Qin Xuebin, Bryda Elizabeth C
Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri;
Department of Neuroscience, Temple University, School of Medicine, Philadelphia, Pennsylvania.
Physiol Genomics. 2016 Aug 1;48(8):626-32. doi: 10.1152/physiolgenomics.00026.2016. Epub 2016 Jul 1.
Effective methods for cell ablation are important tools for examining the anatomical, functional, and behavioral consequences of selective loss of specific cell types in animal models. We have developed an ablation system based on creating genetically modified animals that express human CD59 (hCD59), a membrane receptor, and administering intermedilysin (ILY), a toxin produced by Streptococcus intermedius, which binds specifically to hCD59 to induce cell lysis. As proof-of-concept in the rat, we generated an anemia model, SD-Tg(CD59-HBA1)Bryd, which expresses hCD59 on erythrocytes. Hemolysis is a common complication of inherited or acquired blood disorders, which can result in cardiovascular compromise and death. A rat model that can replicate hemolysis through specific ablation of erythrocytes would allow further study of disease and novel treatments. In vitro, complete lysis of erythrocytes expressing hCD59 was observed at and above 250 pM ILY, while no lysis was observed in wild-type erythrocytes at any ILY concentration (8-1,000 pM). In vivo, ILY intravenous injection (100 ng/g body wt) dramatically reduced the hematocrit within 10 min, with a mean hematocrit reduction of 43% compared with 1.4% in the saline control group. Rats injected with ILY at 500 ng/g intraperitoneally developed gross signs of anemia. Histopathology confirmed anemia and revealed hepatic necrosis, with microthrombi present. These studies validate the hCD59-ILY cell ablation technology in the rat and provide the scientific community with a new rapid conditional targeted ablation model for hemolytic anemia and hemolysis-associated sequelae.
有效的细胞消融方法是研究动物模型中特定细胞类型选择性缺失的解剖学、功能和行为后果的重要工具。我们开发了一种消融系统，该系统基于创建表达人类CD59（hCD59，一种膜受体）的基因改造动物，并给予中间链球菌产生的毒素中间溶素（ILY），它能特异性结合hCD59以诱导细胞裂解。作为在大鼠中的概念验证，我们构建了一个贫血模型，SD-Tg(CD59-HBA1)Bryd，其在红细胞上表达hCD59。溶血是遗传性或获得性血液疾病的常见并发症，可导致心血管功能损害和死亡。一个能够通过特异性消融红细胞来复制溶血的大鼠模型将有助于对疾病和新治疗方法进行进一步研究。在体外，在ILY浓度达到及高于250 pM时观察到表达hCD59的红细胞完全裂解，而在任何ILY浓度（8 - 1000 pM）下野生型红细胞均未观察到裂解。在体内，静脉注射ILY（100 ng/g体重）在10分钟内显著降低了血细胞比容，平均血细胞比容降低了43%，而生理盐水对照组为1.4%。腹腔注射500 ng/g ILY的大鼠出现了明显的贫血症状。组织病理学证实了贫血并揭示存在肝坏死和微血栓。这些研究验证了大鼠中的hCD59 - ILY细胞消融技术，并为科学界提供了一种用于溶血性贫血和溶血相关后遗症的新型快速条件性靶向消融模型。
