Complement factor H Y402H polymorphism results in diminishing CD4+ T cells and increasing C-reactive protein in plasma.

Age-related macular degeneration (AMD) is a common cause of visual loss among the elderly. Genetic variants in the gene encoding complement factor H (CFH) have been identified as an AMD susceptibility gene, however, the mechanistic link is debated. Here, we investigated the link between the CFH Y402H genotype and low-grade inflammation. We recruited 153 healthy individuals, 84 participants with dry stages of AMD, and 148 participants with neovascular AMD. All participants were subjected to detailed retinal examination, and interview regarding comorbidities and lifestyle. Blood samples were analyzed for level of C-Reactive Protein (CRP), white blood cell differential count, and stained with fluorescent antibodies to differentiate CD4+ and CD8+ T cells. CFH Y402H genotyping was performed using an allele-specific polymerase chain reaction genotyping assay. Splenocytes from young and aged wild type and Cfh null mutant C57BL/6J mice were examined for CD4+ and CD8+ T cells. Healthy individuals with the CFH Y402H at-risk polymorphism HH had higher levels of CRP and lower proportions of CD4+ T cells compared to persons with the YH or YY polymorphism (P = 0.037, Chi-square). Healthy individuals with the HH polymorphism displayed lower proportions of CD4+ T cells with ageing (P < 0.01, one-way ANOVA), whereas both young and aged Cfh null mutant mice displayed lower proportions of CD4+ T cells (P < 0.001 and P < 0.05; unpaired t test). Participants with dry AMD and the HH polymorphism had similarly lower proportions of CD4+ T cells (P = 0.024, one-way ANOVA), but no difference in CRP-levels. In the neovascular stage of AMD, there was no difference in proportion of CD4+ cells or CRP levels according to genotype. The risk-associated CFH genotype is associated with an age-related decrease in proportion of CD4+ T cells and increased levels of CRP in healthy individuals. This indicates that decreased complement regulation results in extensive changes in innate and adaptive immune compartments that precede development of AMD.

Vision-related quality of life is selectively affected by comorbidities in patients with geographic atrophy.

BACKGROUND: The atrophic late stage of age-related macular degeneration (AMD) is termed geographic atrophy (GA), and affects visual acuity (VA) as well as quality of life (QoL). Previous studies have found that best-corrected VA (BCVA), the standard vision assessment often underrepresents functional deficits. Therefore, the purpose of this study was to evaluate the correlation between atrophic lesion size, VA and QoL measured with the National Eye Institute Visual Function Questionnaire (VFQ-39) in a Danish population. Moreover, we wanted to evaluate the correlation between comorbidities, behavioural factors, and QoL. METHODS: This was prospective clinical study of 51 patients with GA in one or both eyes, of these 45 patients had bilateral GA. Patients were consecutively included between April 2021 and February 2022. All patients filled in the VFQ-39 questionnaire except the subscales "ocular pain" and "peripheral vision." Lesion size was measured from fundus autoflourescense images, and BCVA was assessed by the Early Treatment Diabetic Retinopathy Study (ETDRS) protocol. RESULTS: We found an overall low score in each VFQ-39 subscale scores reflected by GA. Lesion size and VA were both significantly associated with all VFQ-39 subscale scores except for "general health." VA showed a larger effect on QoL than lesion size. Chronic obstructive pulmonary disease (COPD) was associated with a lower score in the subscale score "general health" but none of the other subscale scores were affected. Cardiovascular disease (CVD) was associated with a lower BCVA as well as in QoL reflected in the subscale scores "poor general vision," "near activities," and "dependency" of VFQ-39. CONCLUSION: Both atrophic lesion size and visual acuity affects QoL in Danish patients with GA, who reports an overall poor QoL. CVD seems to have a negative effect on disease, as well as in VFQ-39 in several subscales, whereas COPD did not affect disease severity or vision-related subscales in VFQ-39.

EX-vivo whole blood stimulation with A2E does not elicit an inflammatory cytokine response in patients with age-related macular degeneration.

Age-related macular degeneration (AMD) is a highly prevalent degenerative disease and a leading cause of vision loss worldwide. Evidence for an inflammatory component in the development of AMD exists, yet the exact mechanisms remain unclear. Bisretinoid N-retinylidene-N-retinylethanolamine (A2E) in retinal pigmental epithelial (RPE) cells, and in extracellular deposits constitutes a hallmark of AMD, but its role in the pathology of AMD is elusive. Here, we tested the hypothesis that A2E is responsible for the heightened inflammatory activity in AMD. To this end, we measured ex vivo mRNA expression of the cytokines TNF-α, IL-6, and IL-10 in whole blood samples after stimulation with A2E in a clinical sample of 27 patients with neovascular AMD and 24 patients with geographic atrophy secondary to AMD. Patients' spouses (n = 30) were included as non-affected controls. After stimulation with A2E, no statistical differences were found in the median expression level of TNF-α, IL-6, IL-10 between the control group, and the neovascular AMD and the geographic atrophy group. Our findings do not support evidence for the hypothesis, that A2E per se contributes to heightened inflammatory activity in AMD.

Patients with myeloproliferative neoplasms and high levels of systemic inflammation develop age-related macular degeneration.

BACKGROUND: Epidemiological data show that myeloproliferative neoplasms (MPNs) are associated with increased risk of neovascular age-related macular degeneration (AMD). However, knowledge about the retinal findings in these patients is lacking. This study was conducted to examine retinal ageing and the prevalence of a hallmark of AMD; drusen, in patients with MPNs. Further, we examine the role of chronic systemic inflammation, considered central in both AMD and MPNs. METHODS: In this single-centre cross-sectional study, we consecutively enrolled 200 patients with MPNs. The study was divided into three substudies. Firstly, we obtained colour fundus photographs from all patients to evaluate and compare the prevalence of drusen with the published estimates from three large population-based studies. Secondly, to evaluate age-related changes in the various retinal layers, optical coherence tomography images were obtained from 150 of the patients and compared to a healthy control group, from a previous study. Thirdly, venous blood was sampled from 63 patients to determine the JAK2V617F allele burden and neutrophil-to-lymphocyte ratio (NLR), a marker of systemic inflammation, in MPN patients with and without drusen. FINDINGS: Patients with MPNs had an increased risk of having large drusen compared to the three population-based studies OR 5·7 (95%CI, 4·1-8·0), OR 6·0 (95%CI, 4·2-8·4) and OR 7·0 (95%CI, 5·0-9·7). Also, we found that the retinal site of drusen accumulation - the Bruch's-membrane-retinal-pigment-epithelium-complex was thicker compared to healthy controls, 0·43µm (95%CI 0·17-0·71, p = 0·0014), but there was no sign of accelerated retinal ageing in terms of thinning of the neuroretina. Further, we found that MPN patients with drusen had a higher level of systemic inflammation than MPN patients with no drusen (p = 0·0383). INTERPRETATION: Patients with MPNs suffer from accelerated accumulation of subretinal drusen and therefore AMD from an earlier age than healthy individuals. We find that the retinal changes are located only between the neuroretina and the choroidal bloodstream. Further, we find that the drusen accumulation is associated with a higher JAK2V617F allele burden and a higher NLR, suggesting that low-grade chronic inflammation is a part of the pathogenesis of drusen formation and AMD. FUNDING: Fight for Sight, Denmark and Region Zealand's research promotion fund.

Distribution of risk alleles in patients with age-related macular degeneration.

INTRODUCTION: Age-related macular degeneration (AMD) is a leading cause of vision loss in elderly people. Several single-nucleotide polymorphisms (SNP) have been shown to either increase or reduce the risk of developing AMD. In this study, we investigated the frequency of ten known risk alleles in a Danish cohort across subtypes of late AMD and explored any relationship to accelerated development of bilateral neovascular AMD. METHODS: A total of 206 participants were included, 73 hereof had neovascular AMD, 57 geographic atrophy (GA), 28 polypoidal choroidal vasculopathy (PCV) and 48 were healthy aged controls. Genotyping was performed using the Kompetitive allele-specific polymerase chain reaction genotyping assay. Participants with neovascular AMD were followed in the clinic for four years and registered as having developed bilateral disease or having persistent unilateral disease. RESULTS: We found that patients with neovascular AMD and GA, but not PCV, had a higher frequency of the risk allele for rs10490924 in age-related maculopathy susceptibility 2 (ARMS2) as well as several SNPs related to the complement pathway. Patients who developed bilateral disease within the four-year follow-up had an increased frequency of the risk-allele for rs1061170 in complement factor H (CFH). CONCLUSIONS: Our results support the notion that ARMS2 and CFH are central in neovascular AMD and GA, and that the risk allele for rs1061170 in CFH is associated with accelerated onset of bilateral neovascular AMD. FUNDING: The Velux Foundation, the Danish Eye Research Foundation, Fight for Sight Denmark, the University of Copenhagen, and Region Zealand funded this study. None of the funding bodies had any role in the design, execution or interpretation of the research performed. TRIAL REGISTRATION: not relevant.

The transcriptome of peripheral blood mononuclear cells in patients with clinical subtypes of late age-related macular degeneration.

BACKGROUND: Peripheral blood mononuclear cells (PBMCs) are implicated in the pathogenesis of age-related macular degeneration (AMD). We here mapped the global gene transcriptome of PBMCs from patients with different clinical subtypes of late AMD. RESULTS: We sampled fresh venous blood from patients with geographic atrophy (GA) secondary to AMD without choroidal neovascularizations (n = 19), patients with neovascular AMD without GA (n = 38), patients with polypoidal choroidal vasculopathy (PCV) (n = 19), and aged control individuals with healthy retinae (n = 20). We isolated PBMCs, extracted RNA, and used microarray to investigate gene expression. Volcano plots identified statistically significant differentially expressed genes (P < 0.05) at a high magnitude (≥30% higher/lower) for GA (62 genes), neovascular AMD (41 genes), and PCV (41 genes). These clinical subtypes differed substantially across gene expression and the following pathways identified in enrichment analyses. In a subgroup analysis, we investigated presence vs. absence of subretinal fibrosis and found 826 differentially expressed genes (≥30% higher/lower, P < 0.05) with relation to mRNA splicing, endothelial migration, and interleukin-1 signaling. CONCLUSIONS: We here map the global gene transcriptome of PBMCs related to clinical subtypes of late AMD and find evidence of subtype-specific immunological involvement. Our findings provide a transcriptomic insight into the systemic immunity associated with AMD.

Optical Coherence Tomography Angiography of Purtscher Retinopathy after Severe Traffic Accident in 16-Year-Old Boy.

PURPOSE: To describe optical coherence tomography (OCT) angiography (OCTA) in a case of Purtscher retinopathy. METHODS: A 16-year-old male underwent ophthalmological examination including color fundus photography, spectral domain OCT, OCTA, and microperimetry. Examination was performed 10 days, 1 month, and 6 months after the trauma. Diagnosis was based on the characteristic clinical presentation. PATIENTS: A single patient case. RESULTS: Only the right eye was affected, and all examinations of the left eye were normal. The visual acuity of the right eye was 0.03 (Snellen equivalent) at 10 days and at one month, improving to 0.16 at 6 months. The imaging confirmed the findings of Purtscher retinopathy with ischemic whitening of the retina and retinal hemorrhages and thickened inner retina on OCT. Microperimetry showed reduced sensitivity in the central macula of the right eye. OCTA revealed nonperfusion in both the superficial and the deep retinal capillary plexus of the right eye. CONCLUSION: The OCTA in traumatic Purtscher retinopathy following traffic accident showed nonperfusion in both the superficial and the deep capillary plexus of the retina. OCTA is a valuable noninvasive diagnostic examination in Purtscher retinopathy, and fluorescein angiography became redundant in this case.

T-cell differentiation and CD56+ levels in polypoidal choroidal vasculopathy and neovascular age-related macular degeneration.

Polypoidal choroidal vasculopathy (PCV) and neovascular age-related macular degeneration (AMD) are prevalent age-related diseases characterized by exudative changes in the macula. Although they share anatomical and clinical similarities, they are also distinctly characterized by their own features, e.g. vascular abnormalities in PCV and drusen-mediated progression in neovascular AMD. PCV remains etiologically uncharacterized, and ongoing discussion is whether PCV and neovascular AMD share the same etiology or constitute two substantially different diseases. In this study, we investigated T-cell differentiation and aging profile in human patients with PCV, patients with neovascular AMD, and age-matched healthy control individuals. Fresh venous blood was prepared for flow cytometry to investigate CD4+ and CD8+ T-cell differentiation (naïve, central memory, effector memory, effector memory CD45ra+), loss of differentiation markers CD27 and CD28, and expression of aging marker CD56. Patients with PCV were similar to the healthy controls in all aspects. In patients with neovascular AMD we found significantly accelerated T-cell differentiation (more CD28-CD27- cells) and aging (more CD56+ cells) in the CD8+ T-cell compartment. These findings suggest that PCV and neovascular AMD are etiologically different in terms of T cell immunity, and that neovascular AMD is associated with T-cell immunosenescence.