Lee Hyun, Zahra David, Vogelzang Alexis, Newton Rebecca, Thatcher Jenny, Quan Annie, So Trina, Zwirner Jörg, Koentgen Frank, Padkjaer Søren B, Mackay Fabienne, Whitfeld Peter L, Mackay Charles R
Immunology and Inflammation Department, Garvan Institute of Medical Research, 384 Victoria Street, Darlinghurst, NSW 2010, Australia.
Nat Biotechnol. 2006 Oct;24(10):1279-84. doi: 10.1038/nbt1248. Epub 2006 Sep 17.
Complement component C5a binds C5a receptor (C5aR) and facilitates leukocyte chemotaxis and release of inflammatory mediators. We used neutrophils from human C5aR knock-in mice, in which the mouse C5aR coding region was replaced with that of human C5aR, to immunize wild-type mice and to generate high-affinity antagonist monoclonal antibodies (mAbs) to human C5aR. These mAbs blocked neutrophil migration to C5a in vitro and, at low doses, both prevented and reversed inflammatory arthritis in the murine K/BxN model. Of approximately 40 mAbs generated to C5aR, all potent inhibitors recognized a small region of the second extracellular loop that seems to be critical for regulation of receptor activity. Human C5aR knock-in mice not only facilitated production of high-affinity mAbs against an important human therapeutic target but were also useful in preclinical validation of the potency of these antagonists. This strategy should be applicable to other important mAb therapeutics.
补体成分C5a与C5a受体（C5aR）结合，促进白细胞趋化作用并释放炎症介质。我们使用来自人C5aR基因敲入小鼠（其中小鼠C5aR编码区被人C5aR编码区取代）的中性粒细胞免疫野生型小鼠，以产生针对人C5aR的高亲和力拮抗剂单克隆抗体（mAb）。这些单克隆抗体在体外阻断中性粒细胞向C5a的迁移，并且在低剂量时，在小鼠K/BxN模型中既能预防又能逆转炎性关节炎。在针对C5aR产生的约40种单克隆抗体中，所有强效抑制剂都识别第二细胞外环的一个小区域，该区域似乎对受体活性的调节至关重要。人C5aR基因敲入小鼠不仅有助于产生针对重要人类治疗靶点的高亲和力单克隆抗体，还可用于这些拮抗剂效力的临床前验证。该策略应适用于其他重要的单克隆抗体治疗药物。
