Keenan Tiarnan D L, Toso Marc, Pappas Chris, Nichols Lisa, Bishop Paul N, Hageman Gregory S
Center for Translational Medicine John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, Utah, United States 2Centre for Ophthalmology & Vision Science, Institute of Human Development, Faculty of Med.
Center for Translational Medicine John A. Moran Eye Center, Department of Ophthalmology and Visual Sciences, University of Utah, Salt Lake City, Utah, United States.
Invest Ophthalmol Vis Sci. 2015 Jul;56(8):4870-9. doi: 10.1167/iovs.15-17009.
To determine the effects of chromosome 1 genotype and cigarette smoking on levels of complement activation and inflammation in the human macula.
Donor macular tissue was stratified into three groups by diplotype at the AMD-associated CFH-to-F13B locus: homozygous "risk" (n = 9, 56-78 years), homozygous neutral (n = 2, 64-79 years), and homozygous "protective" (n = 6, 61-78 years) diplotype. Importantly, all donors were homozygous nonrisk at the ARMS2/HTRA1 locus, so that purely chromosome 1-directed pathways were examined. Immunohistochemistry was performed by using 14 antibodies, mostly against markers of complement and inflammation, followed by confocal microscopy and immunofluorescence quantification (all masked to donor status).
Donors homozygous risk at CFH-to-F13B exhibited significantly higher levels of terminal complement complex (TCC) in macular Bruch's membrane (BM; P = 0.03), choriocapillaris (CC; P = 0.04), and choriocapillaris intercapillary septa (CC IS; P = 0.03), compared to homozygous protected donors. Smoking was associated with increased TCC in BM (P = 0.05), CC IS (P = 0.03), and choroidal stroma (CS; P = 0.01), and with substantially elevated C-reactive protein (CRP) levels in RPE (P = 0.04), BM (P = 0.01), CC (P = 0.05), and CS (P = 0.05). Smoking was associated with higher levels of oxidative stress in macular RPE (P = 0.04) and CS (P = 0.01).
Genetic risk at the CFH-to-F13B locus was associated with higher levels of complement activation at the human macular RPE-choroid interface, as was cigarette smoking. Levels of CRP were substantially elevated in risk donors with smoking history. Examination of human macular tissue from donors with "pure" diplotypes allows assessment of AMD-associated pathways driven solely by CFH-to-F13B. These findings have important implications for identifying chromosome 1-directed pathways and therapeutic targets.
确定1号染色体基因型和吸烟对人黄斑区补体激活水平及炎症的影响。
根据年龄相关性黄斑变性（AMD）相关的CFH至F13B基因座的双倍型，将供体黄斑组织分为三组：纯合“风险”型（n = 9，56 - 78岁）、纯合中性型（n = 2，64 - 79岁）和纯合“保护”型（n = 6，61 - 78岁）双倍型。重要的是，所有供体在ARMS2/HTRA1基因座均为纯合非风险型，以便研究仅由1号染色体引导的途径。使用14种抗体进行免疫组织化学检测，这些抗体大多针对补体和炎症标志物，随后进行共聚焦显微镜检查和免疫荧光定量分析（所有检测均对供体状态保密）。
与纯合保护型供体相比，CFH至F13B基因座为纯合风险型的供体在黄斑布鲁赫膜（BM；P = 0.03）、脉络膜毛细血管（CC；P = 0.04）和脉络膜毛细血管毛细血管间间隔（CC IS；P = 0.03）中的终末补体复合物（TCC）水平显著更高。吸烟与BM（P = 0.05）、CC IS（P = 0.03）和脉络膜基质（CS；P = 0.01）中TCC水平升高相关，并且与视网膜色素上皮（RPE；P = 0.04）、BM（P = 0.01）、CC（P = 0.05）和CS（P = 0.05）中C反应蛋白（CRP）水平大幅升高相关。吸烟与黄斑RPE（P = 0.04）和CS（P = 0.01）中更高水平的氧化应激相关。
CFH至F13B基因座的遗传风险与人类黄斑RPE - 脉络膜界面更高水平的补体激活相关，吸烟也是如此。有吸烟史的风险供体中CRP水平大幅升高。对具有“纯”双倍型供体的人黄斑组织进行检查，有助于评估仅由CFH至F13B驱动的AMD相关途径。这些发现对于确定1号染色体引导的途径和治疗靶点具有重要意义。
