Dzau V J, Devine D, Mudgett-Hunter M, Kopelman R I, Barger A C, Haber E
Clin Exp Hypertens A. 1983;5(7-8):1207-20. doi: 10.3109/10641968309048852.
The use of antirenin antibody and Fab may provide a more specific physiologic tool and potential therapeutic agent than the existing pharmacologic inhibitors. The antibody combining site, by virtue of its larger size than organic compounds, has the capacity for a larger number of intramolecular contacts with its ligands, thus allowing increased selectivity and affinity. Renin-specific Fab obtained through immunization with purified dog renal renin has been studied. Fab had no effect on blood pressure in the sodium replete conscious dog but induced systemic hypotensive responses in the sodium deplete animal or during acute renovascular hypertension. These responses were accompanied with complete suppression of plasma renin and angiotensin II levels. The vasodepressor responses of Fab were comparable to the converting enzyme inhibitor, teprotide. However, the latter induced a greater renal vasodilator effect. Since antibodies and their fragments derived from immune sera are limited in their application to physiologic study with respect to lack of homogeneity, reproducibility and limitation of quantity, we obtained monoclonal antibodies to purified human renal renin. Fusion HR3 yielded 14 renin-antibody secreting clones. Six clones have been isolated and characterized. Isotypes include IgG1 and IgM. Kd's range from 6 X 10(-9) to 7.5 X 10(-10)M renin concentration. Five clones produce antibodies with antienzymatic activity. IC50's of these antibodies range from 1 X 10(-6) to 6 X 10(-8)M. All antibodies are renin-specific and do not bind several nonrenin enzymes and proteins examined. They are also highly species specific, i.e., do not crossreact with mouse, dog, bovine or rat renins but recognize hog renin. These catalytic-site directed antibodies may be highly potent and specific tools for physiologic studies in subhuman primates and man.
与现有的药物抑制剂相比，抗肾素抗体和Fab片段可能提供一种更具特异性的生理学工具和潜在治疗剂。抗体结合位点由于其尺寸大于有机化合物，能够与配体进行更多的分子内接触，从而提高选择性和亲和力。通过用纯化的犬肾肾素免疫获得的肾素特异性Fab片段已得到研究。在钠充足的清醒犬中，Fab片段对血压无影响，但在钠缺乏的动物或急性肾血管性高血压期间可引起全身性降压反应。这些反应伴随着血浆肾素和血管紧张素II水平的完全抑制。Fab片段的血管降压反应与转化酶抑制剂替普罗肽相当。然而，后者诱导出更大的肾血管舒张作用。由于源自免疫血清的抗体及其片段在应用于生理学研究时存在缺乏同质性、可重复性和数量有限的问题，我们获得了针对纯化的人肾肾素的单克隆抗体。融合HR3产生了14个分泌肾素抗体的克隆。已分离并鉴定了6个克隆。亚型包括IgG1和IgM。解离常数（Kd）范围为肾素浓度6×10⁻⁹至7.5×10⁻¹⁰M。5个克隆产生具有抗酶活性的抗体。这些抗体的半数抑制浓度（IC50）范围为1×10⁻⁶至6×10⁻⁸M。所有抗体均对肾素具有特异性，不与所检测的几种非肾素酶和蛋白质结合。它们也具有高度的种属特异性，即不与小鼠、犬、牛或大鼠肾素发生交叉反应，但可识别猪肾素。这些催化位点导向抗体可能是用于亚人类灵长类动物和人类生理学研究的高效且特异的工具。
