interleukin-8 and Geographic-Atrophy

Geographic atrophy (GA) is a clinical phenotype of late age-related macular degeneration (AMD) with no current treatment available. In this study, we investigated markers of chronic inflammation in plasma of patients with GA and how these relate to progression rate.. We prospectively included 42 patients with GA, 41 patients with neovascular AMD, and 27 healthy controls. We quantified levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF) receptor 2, and C-reactive protein (CRP). We adapted an inflammation summary score to cluster conceptually related markers of chronic inflammation. Enlargement rate of the atrophic lesion was measured from fundus autofluorescence images performed at baseline and after 1 year.. Patients with GA showed an increase in proinflammatory markers of IL-6 (P = 0.009), TNF receptor 2 (P = 0.013), and CRP (P = 0.017) compared to healthy controls. We found that IL-8 levels were markedly higher in patients with GA when compared to patients with neovascular AMD (P = 0.013). The inflammation summary score was high in patients with neovascular AMD (P = 0.024), but even higher in patients with GA (<0.001), when compared to healthy controls. GA enlargement was measured in 36 patients, who completed follow-up. Plasma levels of IL-6 had a moderate but significant correlation with GA enlargement rate (R2 = 0.23, P = 0.0035).. Markers of chronic inflammation strongly associates with presence of GA secondary to AMD. Plasma IL-6 possesses predictive ability of progression and constitutes the first known plasma biomarker of disease activity in GA. These findings shed light into a poorly understood clinical phenotype of AMD and highlights the important role of chronic inflammation in GA.

Topics: Aged; Aged, 80 and over; Biomarkers; C-Reactive Protein; Disease Progression; Female; Fluorescein Angiography; Genotyping Techniques; Geographic Atrophy; Humans; Interleukin-6; Interleukin-8; Male; Prospective Studies; Receptors, Tumor Necrosis Factor, Type II; Visual Acuity; Wet Macular Degeneration

To study the association of the single nucleotide polymorphism (SNP) rs4073 in the interleukin-8 (IL-8) promoter region with the diagnosis and age of onset of exudative age-related macular degeneration (AMD) in association with the known genetic risk factors for AMD and tobacco smoking.. Medical records, smoking history and angiograms or fundus photographs of 301 patients with exudative AMD, 72 patients with dry AMD and 119 control subjects were analysed retrospectively. The associations of IL-8 rs4073 A→T, CFH rs1061170 T→C, ARMS2 rs10490924 G→T and C3 rs2230199 C→G SNPs with the presence of AMD and with the age of onset of exudative AMD were analysed.. Younger age of exudative AMD onset was associated with the homozygous AA genotype of IL-8 rs4073 (p = 0.009, Mann-Whitney U-test), CC genotype of CFH rs1061170 (p = 0.016), TT genotype of ARMS2 rs10490924 (p = 0.001) and with current smoking (p = 0.002). The risk alleles C in CFH rs1061170 (p < 0.0001, Pearson chi-square) and T in ARMS2 rs10490924 (p < 0.0001), as well as smoking (p < 0.0001), were more prevalent in AMD patients compared with controls. No association was found between the IL-8 rs4073 genotype and the presence of AMD.. Out of the factors associated with the earlier onset of exudative AMD, only the genotype of IL-8 rs4073 did not appear as a risk factor for AMD in general. IL-8 may have a role in accelerating the development of the choroidal neovascularization in exudative AMD.

Topics: Aged; Aged, 80 and over; Complement C3; Complement Factor H; Female; Genotype; Geographic Atrophy; Humans; Interleukin-8; Male; Middle Aged; Polymerase Chain Reaction; Polymorphism, Single Nucleotide; Promoter Regions, Genetic; Retrospective Studies; Risk Factors; Smoking; Wet Macular Degeneration