Department of Cardiology and Angiology, University Hospital Erlangen, Erlangen, Germany.
Institute of Human Genetics, University of Erlangen-Nuremberg, Erlangen, Germany.
Thromb Res. 2014 Mar;133(3):426-32. doi: 10.1016/j.thromres.2013.12.030. Epub 2013 Dec 30.
The stimulatory effects of CRP (C-reactive protein) on endothelial cells are mainly mediated via FcγRIIa. This receptor exists in two different allotypes bearing either arginine (R131) or histidine (H131) at the extracellular amino acid position 131 of the mature protein, but only FcγRIIa-R131 displays high avidity for CRP. This study investigated the role of the FcγRIIa genotype in CRP-stimulated endothelial cells.
We tested the effects of CRP on expression of the adhesion molecules ICAM-1, VCAM-1, and E-selectin, as well as the endothelial release of pro-inflammatory molecules as a function of the FcγRIIa-genotype (FcγRIIa-H/H131, FcγRIIa-H/R131, FcγRIIa-R/R131) in HUVEC (Human Umbilical Vein Endothelial Cells). HUVEC were grouped according to their FcγRIIa status by genotyping with an allele specific nested-PCR. The expression of ICAM-1, VCAM-1, and E-selectin on HUVEC was detected by flow cytometry. The release of soluble markers (sCD40L, IL-6, IL-8, MCP-1, tPA, sP-selectin, and sVCAM-1) was measured using a multiplex assay for flow cytometry.
CRP-stimulated expression of ICAM-1 and E-selectin was dependent on the specific FcγRIIa-genotype, with most pronounced induction in HUVEC with the FcγRIIa-R/R genotype, followed by H/R and H/H. In accordance with this finding, the supernatants of stimulated HUVEC with the R/R genotype showed significantly higher levels of tPA, MCP-1, and IL-6. Our data show that CRP stimulates the expression of adhesion molecules and the release of soluble markers by HUVEC as a function of the FcγRIIa-genotype. These findings could be relevant in the context of risk stratification in patients with cardiovascular disease.
CRP（C 反应蛋白）对内皮细胞的刺激作用主要通过 FcγRIIa 介导。该受体在成熟蛋白的细胞外氨基酸位置 131 处存在两种不同的同种型，分别携带精氨酸（R131）或组氨酸（H131），但只有 FcγRIIa-R131 对 CRP 表现出高亲和力。本研究探讨了 FcγRIIa 基因型在 CRP 刺激的内皮细胞中的作用。
我们检测了 CRP 对粘附分子 ICAM-1、VCAM-1 和 E-选择素表达的影响，以及作为 FcγRIIa 基因型（FcγRIIa-H/H131、FcγRIIa-H/R131、FcγRIIa-R/R131）功能的内皮细胞释放促炎分子。HUVEC（人脐静脉内皮细胞）根据 FcγRIIa 状态通过等位基因特异性巢式 PCR 进行基因分型。通过流式细胞术检测 ICAM-1、VCAM-1 和 E-选择素在 HUVEC 上的表达。使用流式细胞术的多重分析测量可溶性标记物（sCD40L、IL-6、IL-8、MCP-1、tPA、sP-选择素和 sVCAM-1）的释放。
CRP 刺激的 ICAM-1 和 E-选择素表达依赖于特定的 FcγRIIa 基因型，在具有 FcγRIIa-R/R 基因型的 HUVEC 中诱导最为明显，其次是 H/R 和 H/H。与此发现一致，具有 R/R 基因型的刺激的 HUVEC 的上清液显示出明显更高水平的 tPA、MCP-1 和 IL-6。我们的数据表明，CRP 刺激 HUVEC 表达粘附分子并释放可溶性标记物，这与 FcγRIIa 基因型有关。这些发现可能与心血管疾病患者的风险分层有关。
