Aims Anti-vascular endothelial growth factor compounds are routinely used for the treatment of diabetic macular edema (DME). We aim to evaluate for the existence and magnitude of treatment effect on fellow un-injected eyes. Methods A consecutive group of patients with bilateral DME who received unilateral bevacizumab injections was retrospectively evaluated. Data collected included demographics, ophthalmic and systemic findings, and optical coherence tomography (OCT) measurements of macular thickness. Results Thirty-five patients were evaluated. Mean follow-up was 245 days (range: 30–800), and the mean number of bevacizumab injections was 3.6 (range: 1–11). At end of follow-up, the mean (SD) OCT central subfield thickness reduced by 72±112 micron in the injected eye (from 469±139 to 397±120 micron; P=0.001), while in the non-injected eye it reduced by 49±75 micron (from 380±130 to 331±106 micron; P<0.001). Sixteen injected eyes (45.7%) showed central subfield thickness reduction of ≥50 micron while 10 (28.6%) non-injected eyes showed such thickness reduction. Improved VA following treatment was detected in 14 (40%) injected eyes and in 15 (43%) non-injected eyes. Conclusions Unilateral bevacizumab injections in patients with bilateral DME are often associated with bilateral response. Summary Statement Anti-vascular endothelial growth factor compounds are routinely used for the treatment of diabetic macular edema (DME). In this retrospective study, we show that unilateral bevacizumab injections often result in reduction of the macular thickness in the fellow un-injected eye.

Purpose.: Chemokine signaling and monocytes/macrophages were implicated in the pathogenesis of AMD. We tested the association between chemokines involved in monocyte recruitment and AMD. Methods.: Immunophenotyping for white blood cell (WBC) populations including CD14++CD16- and CD14+CD16+ monocytes, CD19+, CD3+, and CD16+ lymphocytes, and chemokine receptors CCR1, CCR2, CCR5, CX₃CR1, and CXCR4 was performed on peripheral blood from treatment-naïve neovascular AMD (NV-AMD) patients and controls. The mRNA level of chemokine receptors in monocytes was measured with quantitative-PCR. Systemic levels of major chemokine ligands CCL2, CCL5, CCL3, and CXCL10 were evaluated by ELISA. Genotyping was performed for risk SNPs for AMD in the CFH, C3, and HTRA1 genes. Results.: The percentage of WBC subpopulations tested was similar between NV-AMD patients (n = 18) and controls (n = 20). CD14+CD16+ monocyte subpopulation showed a 3.5-fold increased expression of CCR1 (P = 0.039; t-test) and a 2.2-fold increased expression of CCR2 (P = 0.027) in patients compared with controls. Increased CCR1 and CCR2 expression was correlated with each other in patients (R ² = 0.64, P < 0.0001), but not controls (R ² = 0.02, P = 0.57). Increased mRNA levels of CCR1 (1.6-fold, P = 0.037) and CCR2 (1.6-fold, P = 0.007) were found in monocytes from NV-AMD patients. Chemokine receptor expression was not correlated with the presence of risk SNPs, and was not associated with blood chemokine levels. Conclusions.: CCR1 and CCR2 are coupregulated on the CD14+CD16+ monocyte population in NV-AMD patients. These data implicate CD14+CD16+ monocytes and chemokine signaling in AMD. Additional investigation is needed to elucidate the role of these monocytes and their potential as a biomarker or therapeutic target for AMD.

Purpose: Age-related macular degeneration (AMD) is associated with altered gene and protein expression in the retina. We characterize the aqueous humor (AH) proteome in AMD to gain insight into the pathogenesis of the disease and identify potential biomarkers. Methods: AH was collected from age and gender matched neovascular AMD (nvAMD; n = 10) patients and controls (n = 10). AH was pooled to create two samples (nvAMD and control), followed by intensity-based label-free quantification (MS1). Functional and bioinformatic analysis were then performed. A validation set (20 controls, 15 atrophic AMD and 15 nvAMD) was tested via multiplex ELISA for nine differentially expressed proteins according to the MS1 findings. Results: MS1 identified 674 proteins in the AH. 239 proteins were upregulated in nvAMD (nvAMD/control > 2, peptide tags (PT) > 2), and 86 proteins were downregulated (nvAMD/control < 0.5, PT > 2). Functional analysis of proteins upregulated in AMD demonstrated enrichment for platelet degranulation (enrichment score (ES):28.1), negative regulation of endopeptidase activity (ES:18.8), cellular protein metabolic process (ES:11.8), epidermal growth factor-like domain (ES:10.3), sushi/SCR/CCP (ES:10.1), and complement/coagulation cascades (ES:9.2). AMD protein clusters were upregulated for 3/6 (χ2 < 0.05 compared to randomization). Validation via ELISA confirmed MS1 in 2/9 proteins (Clusterin and Serpin A4, P < 0.05), while 3/9 showed differential expression between aAMD and nvAMD (Clusterin, Serpin A4, and TF P < 0.05). Receiver operating characteristic curve calculation identified the area under the curve of 0.82 for clusterin as a biomarker for distinction of AMD. Conclusions: AH proteomics in AMD patients identified several proteins and functional clusters with altered expression. Further research should confirm if these proteins may serve as biomarkers or therapeutic target for the disease.

Mononuclear phagocytes (MPs), including monocytes/macrophages, play complex roles in age-related macular degeneration (AMD) pathogenesis. We reported altered gene-expression signature in peripheral blood mononuclear cells from AMD patients and a chemokine receptor signature on AMD monocytes. To obtain comprehensive understanding of MP involvement, particularly in peripheral circulation in AMD, we performed global gene expression analysis in monocytes. We separated monocytes from treatment-naïve neovascular AMD (nvAMD) patients (n = 14) and age-matched controls (n = 15) and performed microarray and bioinformatics analysis. Quantitative real-time PCR was performed on other sets of nvAMD (n = 25), atrophic AMD (n = 21) and controls (n = 28) for validation. This validated microarray genes (like TMEM176A/B and FOSB) tested, including differences between nvAMD and atrophic AMD. We identified 2,165 differentially-expressed genes (P < 0.05), including 79 genes with log2 fold change ≥1.5 between nvAMD and controls. Functional annotation using DAVID and TANGO demonstrated immune response alterations in AMD monocytes (FDR-P <0.05), validated by randomized data comparison (P < 0.0001). GSEA, ISMARA and MEME analysis found immune enrichment and specific involved microRNAs. Enrichment of differentially-expressed genes in monocytes was found in retina via SAGE data-mining. These genes were enriched in non-classical vs. classical monocyte subsets (P < 0.05). Therefore, global gene expression analysis in AMD monocytes reveals an altered immune-related signature, further implicating systemic MP activation in AMD.

Purpose. Altered iron metabolism was implicated in retinal and macular degeneration. This study was designed to further elucidate iron homeostasis during the course of retinal degeneration in mice. methods. Retinal mRNA and protein expression of transferrin, transferrin receptor, and ceruloplasmin were evaluated during retinal degeneration in rd10 mice and chemokine receptor 2 (ccr2)-deficient mice. Retinal ferritin protein levels, ferritin-bound iron, and total iron were evaluated in rd10 mice. results. Transferrin and ceruloplasmin mRNA levels increased between 2- and 12-fold during the course of retinal degeneration in rd10 mice compared with same-age controls (P < 0.01), whereas transferrin receptor mRNA levels increased only at the late stages of degeneration in rd10 mice (2.7-fold; P = 0.005). Transferrin mRNA also increased in retinas of aged ccr2-deficient mice (1.5-fold; P = 0.05). Transferrin and ceruloplasmin protein levels corroborated with mRNA levels changes in rd10 mice albeit at a lower magnitude. Retinal ferritin protein levels increased between 1.5-fold and 2-fold (P < 0.03) in rd10 mice, and ferritin-bound iron levels increased 1.6-fold in 3-week-old rd10 mice (P = 0.03). Three-week-old rd10 mice also had a 1.4-fold increase in total retinal iron level (P = 0.05). conclusions. Combined with previous reports, these data suggest that retinal degenerations are associated with altered iron homeostasis regardless of the primary insult. Given the potential of iron to generate oxidative injury, its role as a therapeutic target in retinal and macular degenerations should be evaluated.