Fu Huamei, Karlsson Jennie, Björkman Lena, Stenfeldt Anna-Lena, Karlsson Anna, Bylund Johan, Dahlgren Claes
Department of Rheumatology and Inflammation Research, University of Göteborg, Guldhedsgatan 10, S-413 46 Göteborg, Sweden.
J Immunol Methods. 2008 Feb 29;331(1-2):50-8. doi: 10.1016/j.jim.2007.11.005. Epub 2007 Dec 10.
Neutrophils express the G protein-coupled N-formyl peptide receptor (FPR) as well as its closely related homologue, formyl peptide like receptor 1 (FPRL1), and activation of these receptors induce a release of superoxide anions. The magnitude of the responses induced by the two peptide agonists fMLF and WKYMVM, specific for FPR and FPRL1, respectively, was found to be very variable in different neutrophil populations. The ratio between the FPR and FPRL1 triggered respiratory burst was, however, very constant and close to 1. The ratio was changed in neutrophils that were desensitized as well as when the signaling through either of the receptors was inhibited by receptor specific antagonists or by a PIP(2) binding peptide. The FPR/FPRL1 ratio was not changed in primed neutrophils or in differentiated HL-60 cells. We show that the change in the ratio, calculated from the amount of radical release in neutrophils triggered with FPR and FPRL1 specific agonists can be used as a valuable tool to find/identify receptor specific/selective changes mediated by peptides/proteins/drugs, as well as to identify cells from patients or groups of patients that diverge from normal cells in their FPR/FPRL1 triggered functions.
中性粒细胞表达G蛋白偶联的N-甲酰基肽受体（FPR）及其密切相关的同系物甲酰基肽样受体1（FPRL1），这些受体的激活会诱导超氧阴离子的释放。发现分别对FPR和FPRL1具有特异性的两种肽激动剂fMLF和WKYMVM所诱导的反应强度在不同的中性粒细胞群体中变化很大。然而，FPR和FPRL1触发的呼吸爆发之间的比率非常恒定，接近1。在脱敏的中性粒细胞中以及当通过受体特异性拮抗剂或PIP(2)结合肽抑制任一受体的信号传导时，该比率会发生变化。在预激活的中性粒细胞或分化的HL-60细胞中，FPR/FPRL1比率没有变化。我们表明，根据用FPR和FPRL1特异性激动剂触发的中性粒细胞中自由基释放量计算出的比率变化，可作为一种有价值的工具，用于发现/鉴定由肽/蛋白质/药物介导的受体特异性/选择性变化，以及鉴定来自患者或患者群体的细胞，这些细胞在FPR/FPRL1触发的功能方面与正常细胞不同。
