Lebriz Altay

Local complement activation in aqueous humor in patients with age-related macular degeneration

PurposeTo investigate complement activation in aqueous humor and in plasma of patients with neovascular age-related macular degeneration (nAMD).Patients and methodsAqueous humor and EDTA-plasma of 31 nAMD patients and 30 age-matched controls was collected. The levels of the complement factor 3 (C3), the regulators factor H (FH), and factor I (FI), and of the complement activation products Ba, C3a, and the terminal complement complex (sC5b-9) were measured. Associations between complement levels and phenotype were determined using Mann–Whitney U-test.ResultsIn plasma, no significant differences were found between the nAMD group and the control group. In aqueous humor, significantly increased levels of Ba (P=0.002), and C3a (P=0.002) indicate local complement activation in nAMD patients and a trend for a concomitant upregulation of the complement regulators FH (P=0.02) and FI (P=0.04).ConclusionsOur findings provide strong evidence for a local complement dysregulation in nAMD patients.

Comparison of subthreshold micropulse laser (577 nm) treatment and half-dose photodynamic therapy in patients with chronic central serous chorioretinopathy

PurposeTo compare the short-term treatment outcome of the 577 nm subthreshold micropulse laser (SML) and half-dose photodynamic therapy (PDT) in patients with chronic central serous chorioretinopathy (cCSC) and persistent subretinal fluid (SRF).MethodsThis retrospective study included 100 eyes of 100 consecutive patients who were treated with the 577 nm SML (Supra Scan, Quantel Medical) (n=42) or half-dose PDT (n=58) for cCSC. The treatment was applied at the leakage sites in the fluorescein and indocyanine green angiography. The treatment success was evaluated 6 weeks after treatment using best-corrected visual acuity, central retinal thickness, and resolution of SRF in spectral domain optical coherence tomography.ResultsPatients showed treatment response more often in the SML group compared with the PDT group (treatment response after SML: 33 eyes (79%), PDT: 34 eyes (59%), P=0.036, χ2 test). The CRT decreased significantly after both treatments (mean CRT before SML: 445±153 μm, after SML: 297±95, P<0.001; mean CRT before PDT: 398±88 μm, after PDT: 322±93 μm, P<0.001, Wilcoxons signed-rank test). The decrease in CRT was statistically significantly higher in the SML group (decrease in CRT after SML: −148±163 μm, after PDT: −76±104 μm, P=0.041, Mann–Whitney U-test).ConclusionsBoth the half-dose PDT and the 577 nm SML are potent treatments for cCSC with persistent SRF. More patients showed treatment response to the SML treatment and SML leads to a greater decrease in CRT.

GWAS study using DNA pooling strategy identifies association of variant rs4910623 in OR52B4 gene with anti-VEGF treatment response in age-related macular degeneration

Pooled DNA based GWAS to determine genetic association of SNPs with visual acuity (VA) outcome in anti-vascular endothelial growth factor (anti-VEGF) treated neovascular age-related macular degeneration (nAMD) patients. We performed pooled DNA based GWAS on 285 anti-VEGF treated nAMD patients using high density Illumina 4.3 M array. Primary outcome was change in VA in Early Treatment Diabetic Retinopathy Study (ETDRS) letters after 6 months of anti-VEGF treatment (patients who lost ≥5 ETDRS letters classified as non-responders and all remaining classified as responders). GWAS analysis identified 44 SNPs of interest: 37 with strong evidence of association (p < 9 × 10−8), 2 in drug resistance genes (p < 5 × 10−6) and 5 nonsynonymous changes (p < 1 × 10−4). In the validation phase, individual genotyping of 44 variants showed three SNPs (rs4910623 p = 5.6 × 10−5, rs323085 p = 6.5 × 10−4 and rs10198937 p = 1.30 × 10−3) remained associated with VA response at 6 months. SNP rs4910623 also associated with treatment response at 3 months (p = 1.5 × 10−3). Replication of these three SNPs in 376 patients revealed association of rs4910623 with poor VA response after 3 and 6 months of treatment (p = 2.4 × 10−3 and p = 3.5 × 10−2, respectively). Meta-analysis of both cohorts (673 samples) confirmed association of rs4910623 with poor VA response after 3 months (p = 1.2 × 10−5) and 6 months (p = 9.3 × 10−6) of treatment in nAMD patients.

A Review of Subthreshold Micropulse Laser for Treatment of Macular Disorders

Micropulse laser treatment is an alternative to the conventional continuous-wave laser for the treatment of retinal or macular diseases. In contrast to the conventional laser, the therapeutic effect of the subthreshold micropulse laser is not accompanied by thermal retinal damage. This fact is of particular importance when a treatment near the fovea is required. Micropulse treatment is applied in indications such as central serous chorioretinopathy (CSC), diabetic macular edema (DME), or macular edema due to retinal vein occlusion (RVO). This review outlines and discusses the published literature of subthreshold micropulse laser treatment for CSC, DME, and macular edema after RVO.

Association of a Haplotype in the NR3C2 Gene, Encoding the Mineralocorticoid Receptor, With Chronic Central Serous Chorioretinopathy

Importance Chronic central serous chorioretinopathy (cCSC) is a chorioretinal disease with unknown disease etiology. The glucocorticoid receptor and the mineralocorticoid receptor, 2 glucocorticoid-binding receptors, might be involved in the pathogenesis of cCSC. Objective To assess the association of functional variants and haplotypes in the glucocorticoid receptor (NR3C1) and mineralocorticoid receptor (NR3C2) genes with cCSC. Design, Setting, and Participants In this case-control genetic association study, 336 patients with cCSC and 1314 unaffected controls, collected at 3 university medical centers from September 1, 2009, to May 1, 2016, underwent KASP genotyping for selected variants in NR3C1 (rs56149945, rs41423247, and rs6198) and NR3C2 (rs2070951 and rs5522). Main Outcomes and Measures Genetic associations of 3 NR3C1 variants and 2 NR3C2 variants with cCSC. Results Among the 336 patients (274 men and 62 women; mean [SD] age, 52 [10] years), after correction for multiple testing, rs2070951 in the NR3C2 gene was significantly associated with cCSC (odds ratio, 1.29; 95% CI, 1.08-1.53; P = .004). Moreover, the GA haplotype of single-nucleotide polymorphisms rs2070951 and rs5522 in NR3C2 conferred risk for cCSC (odds ratio, 1.39; 95% CI, 1.15-1.68; P = .004), whereas the CA haplotype decreased risk for cCSC (odds ratio, 0.72; 95% CI, 0.60-0.87; P < .001). Three known variants in NR3C1 that alter the activity of the glucocorticoid receptor (rs56149945, rs41423247, and rs6198) were not associated with cCSC. Conclusions and Relevance In this study, the variant rs2070951 and the GA haplotype in NR3C2 were associated with an increased risk for cCSC. Results of this genetic study support a possible role for the mineralocorticoid receptor in the pathogenesis of cCSC. Since these haplotypes have previously been associated with perceived stress, this study provides a clue to bridging clinical risk factors for cCSC to underlying genetic associations.

A Novel Complotype Combination Associates with Age-Related Macular Degeneration and High Complement Activation Levels in vivo

The complement system is the first line of defense against foreign intruders, and deregulation of this system has been described in multiple diseases. In age-related macular degeneration (AMD), patients have higher complement activation levels compared to controls. Recently, a combination of three single nucleotide polymorphisms (SNPs) in genes of the complement system, referred to as a complotype, has been described to increase complement activation in vitro. Here we describe a novel complotype composed of CFB (rs4151667)-CFB (rs641153)-CFH (rs800292), which is strongly associated with both AMD disease status (p = 5.84*10−13) and complement activation levels in vivo (p = 8.31*10−9). The most frequent genotype combination of this complotype was associated with the highest complement activation levels in both patients and controls. These findings are relevant in the context of complement-lowering treatments for AMD that are currently under development. Patients with a genetic predisposition to higher complement activation levels will potentially benefit the most of such treatments.

Association of Hyperreflective Foci Present in Early Forms of Age-Related Macular Degeneration With Known Age-Related Macular Degeneration Risk Polymorphisms

PURPOSE We evaluated the association of hyperreflective foci (HF) observed in early and intermediate age-related macular degeneration (AMD) with known AMD risk alleles. METHODS In this pilot case-control study, HF were defined as lesions with reflectivity equal or higher than the retinal pigment epithelium band in spectral domain optical coherence tomography (SDOCT). Hyperreflective foci in the outer nuclear layer and photoreceptor complex were evaluated in 518 individuals with early and intermediate AMD. Definite presence of HF was defined as at least 10 HF in all SDOCT scans. Genotyping was performed for 22 single nucleotide polymorphisms (SNPs). Associations between AMD severity stages, HF, and SNPs were determined by logistic regression analyses. RESULTS Hyperreflective foci (n ≥ 10) were significantly associated with AMD severity and the association was strongest with intermediate AMD (odds ratio [OR], 8.45; P = 1.092*10-8). Independently, HF showed associations with ARMS2 rs104909/HtRA1 rs11200638 (OR, 1.64; P = 0.017), CFH rs1061170 (OR, 1.70; P = 0.011), and APOE4/TOMM40 rs2075650 (OR, 2.26; P = 0.005) variants. Within the group of intermediate AMD, associations were similar (ARMS2 rs104909/HtRA1 rs11200638 OR, 1.79, P = 0.010; CFH rs1061170 OR, 1.77, P = 0.013; APOE4/TOMM40 rs2075650 OR, 1.98; P = 0.034) and showed additional trending associations with VEGFA rs943080 variant (OR, 0.59; P = 0.024). After Bonferroni-correction for 22 SNPs, none of the associations was statistically significant (P ≤ 0.0023). CONCLUSIONS The presence of HF is related to AMD severity. Despite limited power of this pilot study, our results suggest an association of HF with polymorphisms in ARMS2/HTRA1, CFH, APOE4/TOMM40, and VEGFA genes which could be triggered by modification of the extracellular matrix, altered complement system or lipid metabolism.

Genetics of Unilateral and Bilateral Age-Related Macular Degeneration Severity Stages

Background Age-related macular degeneration (AMD) is a common disease causing visual impairment and blindness. Various gene variants are strongly associated with late stage AMD, but little is known about the genetics of early forms of the disease. This study evaluated associations of genetic factors and different AMD stages depending on unilateral and bilateral disease severity. Methods In this case-control study, participants were assigned to nine AMD severity stages based on the characteristics of each eye. 18 single nucleotide polymorphisms (SNPs) were genotyped and attempted to correlate with AMD severity stages by uni- and multivariate logistic regression analyses and trend analyses. Area under the receiver operating characteristic curves (AUC) were calculated. Results Of 3444 individuals 1673 were controls, 379 had early AMD, 333 had intermediate AMD and 989 showed late AMD stages. With increasing severity of disease and bilateralism more SNPs with significant associations were found. Odds ratios, especially for the main risk polymorphisms in ARMS2 (rs10490924) and CFH (rs1061170), gained with increasing disease severity and bilateralism (exemplarily: rs1061170: unilateral early AMD: OR = 1.18; bilateral early AMD: OR = 1.20; unilateral intermediate AMD: OR = 1.28; bilateral intermediate AMD: OR = 1.39, unilateral geographic atrophy (GA): OR = 1.50; bilateral GA: OR = 1.71). Trend analyses showed p<0.0001 for ARMS2 (rs10490924) and for CFH (rs1061170), respectively. AUC of risk models for various AMD severity stages was lowest for unilateral early AMD (AUC = 0.629) and showed higher values in more severely and bilaterally affected individuals being highest for late AMD with GA in one eye and neovascular AMD in the other eye (AUC = 0.957). Conclusion The association of known genetic risk factors with AMD became stronger with increasing disease severity, which also led to an increasing discriminative ability of AMD cases and controls. Genetic predisposition was also associated with the disease severity of the fellow-eye, highlighting the importance of both eyes in AMD patients.

Role of the Complement System in Chronic Central Serous Chorioretinopathy: A Genome-Wide Association Study

Importance To date, several targeted genetic studies on chronic central serous chorioretinopathy (cCSC) have been performed; however, unbiased genome-wide studies into the genetics of cCSC have not been reported. To discover new genetic loci associated with cCSC and to better understand the causative mechanism of this disease, we performed a genome-wide association study (GWAS) on patients with cCSC. Objective To discover new genetic loci and pathways associated with cCSC and to predict the association of genetic variants with gene expression in patients with cCSC. Design, Setting, and Participants This case-control GWAS was completed in the general community, 3 referral university medical centers, and outpatient care on Europeans individuals with cCSC and population-based control participants. Genotype data was collected from May 2013 to August 2017, and data analysis occurred from August 2017 to November 2017. Main Outcomes and Measures Associations of single-nucleotide polymorphisms, haplotypes, genetic pathways, and predicted gene expression with cCSC. Results A total of 521 patients with cCSC (median age, 51 years; interquartile range [IQR], 44-59 years; 420 [80.6%] male) and 3577 European population-based control participants (median age, 52 years; IQR, 37-71 years; 1630 [45.6%] male) were included. One locus on chromosome 1 at the complement factor H (CFH) gene reached genome-wide significance and was associated with an increased risk of cCSC (rs1329428; odds ratio [OR], 1.57 [95% CI, 1.38-1.80]; P = 3.12 × 10−11). The CFH haplotypes H1 and H3 were protective for cCSC (H1: OR, 0.64 [95% CI, 0.53-0.77]; P = 2.18 × 10−6; H3: OR, 0.54 [95% CI, 0.42-0.70]; P = 2.49 × 10−6), whereas haplotypes H2, H4, H5, and the aggregate of rare CFH haplotypes conferred increased risk (H2: OR, 1.57 [95% CI, 1.30-1.89]; P = 2.18 × 10−6; H4: OR, 1.43 [95% CI, 1.13-1.80]; P = 2.49 × 10−3; H5: OR, 1.80 [95% CI, 1.36-2.39]; P = 4.61 × 10−5; rare haplotypes: OR, 1.99 [95% CI, 1.43-2.77]; P = 4.59 × 10−5). Pathway analyses showed involvement of the complement cascade and alternative open reading frame (ARF) pathway in cCSC. Using PrediXcan, we identified changes in predicted expression of complement genes CFH, complement factor H related 1 (CFHR1), complement factor related 4 (CFHR4), and membrane cofactor protein (MCP/CD46). Additionally, the potassium sodium-activated channel subfamily T member 2 (KCNT2) and tumor necrosis factor receptor superfamily member 10a (TNFRSF10A) genes were differentially expressed in patients with cCSC. Conclusions and Relevance In this GWAS on cCSC, we identified a locus on chromosome 1 at the CFH gene that was significantly associated with cCSC, and we report protective and risk-conferring haplotypes in this gene. Pathway analyses were enriched for complement genes, and gene expression analysis suggests a role for CFH, CFHR1, CFHR4, CD46, KCNT2, and TNFRSF10A in the disease. Taken together, these results underscore the potential importance of the complement pathway in the causative mechanisms of cCSC.

Retinal Nerve Fiber Loss in Anti-VEGF Therapy for Age-Related Macular Degeneration Can Be Decreased by Anterior Chamber Paracentesis

Purpose: To analyze peripapillary retinal nerve fiber layer thickness (RNFLT) change after long-term intravitreal anti-VEGF therapy. Patients with regular anterior chamber paracentesis (ACP) prior to intravitreal injections (IVIs) were compared to those without ACP. Methods: Neovascular age-related macular degeneration (nAMD) was treated in a pro re nata regimen with a minimum of 9 IVIs. RNFLT change was determined in spectral domain optical coherence tomography. Results: In 32 patients without ACP, mean RNFLT loss (-2.16 ± 3.60 µm) was significantly higher than in 44 patients with regular ACP (0.16 ± 3.60; p = 0.029). Both groups were comparable in age (75.0 vs. 76.8 years; p = 0.35), number of IVIs (16.2 vs. 16.6; p = 0.98), and observational time (30.0 vs. 32.3 months; p = 0.32). In patients without ACP, RNFLT loss was higher compared to IVI-naive fellow eyes (p = 0.005), whereas in ACP patients, no difference was detected (p = 0.5). Conclusions: A moderate RNFLT loss is found in nonglaucomatous patients after injection therapy for nAMD. As it is decreased with regular ACP, tight management of intraocular pressure seems advisable.