Localisé entre l'Epithélium Pigmentaire Rétinien (EPR) et les segments externes des photorécepteurs, l'espace sous-rétinien est une zone immunosuppressive ; régulée par des signaux comme la thrombospondine-1 (TSP-1) ou Fas Ligand (FasL), qui empêchent l'accumulation des phagocytes mononucléés (PMs), en particulier des monocytes inflammatoires. La Dégénérescence Maculaire Liée à l'Age (DMLA) est associée à une rupture de l'immunosuppression de cet espace, et s'accompagne d'une accumulation de PMs ; causant la mort des photorécepteurs, la dédifférenciation de l'EPR et une néovascularisation pathologique. Des études d'associations génétiques ont établi un lien entre la DMLA et un haplotype qui affecte le locus 10q26, qui contient trois gènes : PLEKHA1, ARMS2 et HTRA1. L'haplotype est associé à une augmentation de la transcription de HTRA1 dans les lymphocytes ou les cellules de l'EPR. HTRA1 code pour une sérine protéase qui a une multitude de substrats ; mais le mécanisme par lequel elle pourrait être impliquée dans la pathogenèse de la DMLA reste inconnu. TSP-1 est une glycoprotéine exprimée par l'EPR, les macrophages résidents et inflammatoires. Le domaine C-terminal de TSP-1 contient deux séquences VVM qui peuvent chacune interagir avec un récepteur CD47. Dans cette étude, nous montrons que HTRA1 clive TSP-1 et inhibe l'élimination des PMs régulée par l'interaction entre TSP-1 et CD47 à l'état physiologique, in vitro et in vivo. L'activation pharmacologique de CD47 nous a permis d'annuler les effets pro-inflammatoires de HTRA1 et pourrait représenter un espoir thérapeutique pour le contrôle de la progression de la DMLA chez les patients porteurs de l'haplotype à risque. / Localized between the Retinal Pigment Epithelium (RPE) and the photoreceptors outer segments, the subretinal space is an immunosuppressive zone, mediated by signals such as Thrombospondin-1 (TSP-1), Fas Ligand (FasL) that prevent the accumulation of Mononuclear Phagocytes (MPs) and in particular pathogenic inflammatory monocytes. Age related Macular Degeneration (AMD) is associated with a breakdown of this immunosuppressivity and an accumulation of MPs, which causes photoreceptor degeneration, RPE dedifferentiation and pathological neovascularization. Genome association studies showed a strong link between AMD and a relatively common haplotype of 10q26 locus that contains the PLEKHA1, ARMS2 and HTRA1 genes. The disease haplotype is associated with increased HTRA1 transcription in cell types such as lymphocytes and RPE cells. HTRA1 is a serine protease with a number of substrates, but the mechanism by which it might be involved in AMD pathogenesis is unknown. TSP-1 is a glycoprotein expressed by RPE, resident macrophages and inflammatory macrophages. The C-terminal domain of TSP-1 contains two VVM sequences that can each interact with a CD47 receptor. We show that HTRA1 induced subretinal MP accumulation is dependent on TSP-1 deactivation in an RPE/Mo co-culture model and in a laser induced inflammation model in vivo. This pathogenic effect of HTRA1 was reversible by synthetic CD47 agonists. Our study reveals a comprehensive mechanism how the risk-allele 10q26 participates in the pathogenesis of AMD and opens new therapeutic avenues to restore subretinal immunosuppressivity and inhibit the inflammation-dependent neurodegeneration.

Age related macular degeneration (AMD) is a public health concern in an aging society. The retinal pigment epithelium (RPE) layer of the eye is a principal site of pathogenesis for AMD. Morphological characteristics of the cells in the RPE layer can be used to discriminate age and disease status of individuals. In this thesis three genotypes of mice of various ages are used to study the predictive abilities of these characteristics. The disease state is represented by two mutant genotypes and the healthy state by the wild-type. Classification analysis is applied to the RPE morphology from the different spatial regions of the RPE layer. Variable reduction is accomplished by principal component analysis (PCA) and classification analysis by the k-nearest neighbor (k-NN) algorithm. In this way the differential ability of the spatial regions to predict age and disease status by cellular variables is explored.

Darbo uždaviniai: 1. Nustatyti pradinės AGDD paplitimą vidutinio amžiaus (40 – 64 metų) pacientų, sergančių IŠL grupėje bei atsitiktinėje to paties amžiaus Kauno miesto gyventojų imtyje. 2. Palyginti pacientų, sergančių tik IŠL ir IŠL bei pradinės AGDD klinikinius duomenis. 3. Nustatyti MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) genotipų dažnį bei genotipų derinių įtaką AGDD susiformavimui. 4. Nustatyti MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) genotipų dažnį esant minkštoms ir kietoms drūzoms, sergant AGDD. 5. Nustatyti MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) genotipų dažnį bei genotipų derinių įtaką AGDD ir IŠL drauge bei tik IŠL pasireiškimui. 6. Nustatyti funkcinio kontrastinio jautrumo tyrimo rodmenis pacientams, sergantiems pradine lengva ir pradine vidutine AGDD bei spalvų juslės pokyčius sergantiems pradine AGDD, ir oftalmologiškai sveikiems pacientams. / The goals were as follows: 1. To determine the prevalence of AMD in patients with IHD and compare with the prevalence in a random sample of Kaunas population (at 40-64 yrs old). 2. To compare the main clinical characteristics of the patients exhibiting early AMD and IHD together with the patients with IHD alone. 3. To determine the frequency of the genotypes of the matrix metalloproteinases (MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T)), and genotype combinations that have an influence on the development of early AMD. 4. To determine the frequency of the genotypes of the matrix metallo¬proteinases (MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T)), in early AMD patients with soft or hard drusen. 5. To determine the frequency of the genotypes of the matrix metallo¬proteinases (MMP-2 (-735 C/T), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T)), and the influence of genotype combi¬na¬tions on the development of AMD and IHD together, and only on IHD development. 6. To determine the results of functional acuity contrast sensitivity test in patients with early mild and early intermediate AMD, and color contrast sensitivity in patients with AMD, and in ophthalmologically healthy patients.

Didėjant vyresnių žmonių populiacijai amžinė geltonosios dėmės degeneracija (AGDD) yra vis dažnesnė vyresnio nei 50 metų amžiaus žmonių negrįžtamo regos netekimo priežastis. AGDD prevencinės priemonės bei gydymo galimybės ribotos, nes ligos etiopatogenezė iki šiol nėra visiškai aiški. Disertacinio darbo metu įvertintos AGDD ir išeminės širdies ligos (IŠL) sąsajos, atsižvelgiant į vainikinių arterijų aterosklerozinius pažeidimus. Pirmą kartą analizuota SCARB1 rs5888 C/T genotipų įtaka AGDD ir IŠL pasireiškimui. Tyrimo rezultatai parodė, kad AGDD ir IŠL, kai vainikinėse arterijose yra aterosklerozinių pažeidimų (IŠLath+), sieja bendri, šių ligų pasireiškimo galimybę didinantys, klinikiniai veiksniai ir oksidacinis stresas. Nustatytas „apsauginis“ SCARB1 rs5888 T/T genotipas, mažinantis AGDD ir IŠLath+, bei „rizikingas“ SCARB1 rs5888 C/T genotipas, didinantis AGDD+IŠLath+ galimybę. Pritaikius matematinės morfologijos metodus, nustatyta, jog sergantiems vėlyvąja AGDD SCARB1 rs5888 „rizikingas“ genetinis variantas susijęs su didesniu centrinės tinklainės dalies pažeidimo plotu. Bendrų AGDD ir IŠL patogenezinių grandžių tyrimas suteikia naujos informacijos apie AGDD etiologiją, patogenezę ir galbūt pasitarnaus efektyvaus gydymo bei prevencijos krypčių kūrimui. Tyrimo metu taikyti morfometriniai geltonosios dėmės pažaidos ploto matavimai gali būti naudojami gydytojų-oftalmologų klinikinėje praktikoje, siekiant tiksliau įvertinti centrinės tinklainės dalies pokyčius dinamikoje... [toliau žr. visą tekstą] / Age-related macular degeneration (ARMD) is the commonest cause of blindness among persons over the age of 50 and its prevalence is likely to increase as a consequence of population ageing. ARMD is a disorder of unknown cause and pathogenesis, therefore current options for ARMD prevention and treatment are limited. In the recent study the associations between ARMD and CAD, according the angiographic findings of atherosclerosis in the coronary arteries, were analyzed. The oxidative stress impact and clinical factors determining susceptibility to ARMD and CADath+, separately and common susceptibility factors for both diseases prediction were ascertained. Analysis of novel genetic biomarker, the rs5888 variant of SCARB1 gene, identified the „protective“ SCARB1 rs5888 TT genotype, associated with the lower risk of ARMD and CADath+, and a „risk-determining“ CT genotype, determining higher ARMD+CADath+ risk. The evaluation of macular lesion area by using the methods of mathematical morphology revealed that in late stage ARMD subjects carriers of SCARB1 rs5888 CT genotype the area of macular lesion was larger than in TT genotype carriers. New information about ARMD and CAD discovered additional knowledge about ARMD etiopathogenesis and might be helpfull in search of new treatments or strategies for ARMD prevention. Evaluation of macular lesion area by mathematical morphology methods used in this study may be useful in ophthalmological practice to monitor the dynamics of ARMD.

This research was designed to address important issues for the effective prescription of, and training in the use of, magnifiers for reading patients with visual impairment. The emphasis was on the development of simple methods of assessment and training that could be easily implemented, at no great cost, by low vision practitioners in clinical practice. To ensure that the results would be widely applicable, the research focused on subjects with age-related macular degeneration (AMD) using stand magnifiers (being the most common cause of low vision and the most commonly prescribed magnifiers respectively). From this research, modifications to the current methods of reading rehabilitation are suggested to more effectively improve low vision reading for the millions of people with low vision around the world. The magnification and reading performance achieved with the magnifier determined by the fixed acuity reserve method was as valid as that achieved with the magnifier determined by the individual acuity reserve method. The fixed acuity reserve is a simpler method to calculate the required magnification, as it requires only near visual acuity and the patient's goal reading task. This method was primarily used to select the appropriate illuminated stand magnifiers for the subjects participating in the subsequent studies and is recommended for use as the starting point in clinical low vision practice. The main study of this thesis was a longitudinal investigation of the benefit of large print reading practice on reading performance with stand magnifiers. Instead of the intensive training programs on magnifier use which have been suggested by previous studies, this study aimed to investigate the effect of simple large print reading practice, under either full or restricted field of view (the latter simulated by a practice stand), on reading rate with stand magnifiers for subjects with AMD. The experimental hypothesis was that reading practice prior to the prescription of stand magnifiers would improve reading performance with the stand magnifiers for subjects with AMD. As previous studies have shown, reading rate reduced when a stand magnifier was first introduced. One week of reading practice on large print, with or without a reduced field of view, gave an improvement in reading rate with the stand magnifier for passages of text (such that the reading rates with and without magnifiers were not significantly different). There was a suggestion that this practice may give a more rapid improvement in reading rate than that achieved by the control subjects who did not do any large print reading practice, but this did not reach statistical significance. Even very brief reading with the stand magnifiers by the control subjects gave some improvement in reading rate. Therefore, home or in-office reading practice on large print or with magnifiers is recommended for patients with AMD before magnifiers are prescribed. Subjects who had neither reading practice nor exposure to the magnifier prior to its prescription required two weeks practice using their stand magnifiers to achieve their maximum reading rate. This suggests that home practice in using stand magnifiers is beneficial and a follow up visit is recommended two weeks after the provision of a magnifier to assess any change in reading rate. If no improvement in the magnifier reading rate is found or the rate is less than the reading rate on large print without a magnifier, further investigations of the patients' vision and/or their magnifier manipulation strategy are necessary. In the last study, a simple method aimed at alleviating difficulties with magnifier manipulation and navigation, the attachment of a line guide to the base of the stand magnifier, was investigated using both objective methods (recording magnifier movements and reading rate measures) and subjective methods (simple questionnaire). Although there was no improvement in the objective measures of reading or navigation performance with the line guide, more than half of the subjects with low vision preferred to have the line guide on their stand magnifiers. This suggests that the objective measures might not be sensitive enough to predict the subjective response, or that other factors that were not measured in this study influenced subjects' preferences in selecting the line guide (e.g., psychological support provided by the line guide in reading orientation). Clinically, the subjective response of patients to the use of low vision aids as well as their motivation are important criteria for success in low vision rehabilitation. There was a tendency for less experienced users to prefer the line guide to assist their use of the stand magnifier for reading. Therefore, a line guide could be offered as a preliminary training aid when stand magnifiers are first prescribed for AMD patients. Possible improvements to the design of the line guide were identified. Further research is required to assess the benefits of this or similar devices for new magnifier users and to understand the difficulties that people with visual impairment have with page navigation in order to determine improved methods of training navigation strategies. The unique contribution of this study to the field of low vision rehabilitation is that the benefit of short-term reading practice, on large print or with magnifiers, as simple, cheap methods of enhancing reading performance with stand magnifiers was demonstrated. The results of this study have led to the development of recommendations for assessing and training AMD patients who are prescribed stand magnifiers.

La Dégénérescence Maculaire Liée à l'Age (DMLA) constitue dans les pays industrialisés la 1ère cause de cécité chez les personnes de plus de 50 ans, et représente un enjeu majeur de santé publique d'autant plus important que le vieillissement de la population ne fait que s'accroître. La forme atrophique de cette maladie, pour laquelle il n'existe actuellement aucun traitement, est notamment caractérisée par une inflammation sous-rétinienne associée une dégénérescence des photorécepteurs, et conduit à une perte progressive de la vision centrale pouvant aller jusqu'à la cécité. Nos résultats montrent qu'au stade précoce de la maladie (MLA) on peut déjà observer de nombreux phagocytes mononucléaires (PM) dans l'espace sous-rétinien, en contact avec les drusen. Ces PM expriment de l'apolipoprotéine E (APOE), protéine impliquée dans l'homéostasie lipidique et la régulation de réponses inflammatoires, qui est retrouvée dans les drusen des patients atteints de DMLA, et dont le variant génétique APOε2 est associé à un risque élevé de développer une DMLA. Grâce à l'utilisation de souris Cx3cr1GFP/GFP déficientes en CX3CR1, un récepteur de chimiokine, et de souris humanisées APOε2, les travaux présentés ici démontrent que l'APOE exerce un rôle pro-inflammatoire conduisant de manière dose-dépendante à une altération du privilège immun sous-rétinien. Cet environnement immunosuppresseur est dépendant du FasL exprimé par l'épithélium pigmentaire rétinien (EPR), et empêche en condition physiologique la présence de cellules inflammatoires dans la rétine externe. Nos résultats montrent que l’APOE stimule de manière autocrine la sécrétion d’IL-6 par les PM, possiblement par un mécanisme impliquant une activation des Toll-like receptors (TLR) et de leur corécepteur CD36. Nous montrons que l’IL-6 inhibe l’expression de FasL sur l’EPR et altère sa capacité de clairance sous-rétinienne, ce qui facilite la survie des PM infiltrants au contact des photorécepteurs. La persistance de cette inflammation pathologique dans la rétine externe conduit au cours du vieillissement à une dégénérescence des photorécepteurs, phénomène qui peut est inhibé chez des souris déficientes en APOE. Ensemble, ces résultats permettent d’apporter une explication inédite au risque élevé de développer une DMLA pour les porteurs de l’allèle APOε2, et pourrait ouvrir la voie vers de nouvelles perspectives thérapeutiques. / Age-related Macular Degeneration (AMD) is the first cause of blindness in people over 50 year old in industrialized countries, and represents a major public health concern as the population of elderly is more and more increasing. The atrophic form of the disease, for which there is currently no treatment available, is characterized by subretinal inflammation associated with photoreceptor degeneration and leads to a progressive loss of central vision that can lead to blindness. Our results show many mononuclear phagocytes (MP) are already present at the early stage of the disease (MLA), in the subretinal space and in apposition with drusen. These PM express apolipoprotein E (APOE), a protein involved in lipid homeostasis and the regulation of inflammatory responses, which is found in drusen in patients with AMD, and whose genetic APOε2 variant is associated with a high risk of developing AMD. Using Cx3cr1GFP/GFP mice (deficient in CX3CR1, a chemokine receptor) and humanized APOε2 mice, the work presented herein demonstrates that APOE exerts a pro-inflammatory role leading to a dose-dependent alteration of the subretinal immune privilege. This immunosuppressive environment is dependent upon FasL expression by the retinal pigment epithelium (RPE), and prevents in physiological condition the presence of inflammatory cells in the outer retina. Our results show that APOE stimulates in an autocrine fashion the secretion of IL -6 by PM, possibly through a mechanism involving activation of Toll- like receptors (TLR) and their coreceptor CD36. We show that IL-6 inhibits the expression of FasL on the RPE and impairs its subretinal clearance capacity, which facilitates the survival of infiltrating PM in contact with photoreceptors. The persistence of a pathological inflammation in the outer retina leads to age-dependent photoreceptor degeneration, which can be inhibited in APOE-deficient mice. Taken together, these results provide novel rationale for the higher risk of developing AMD for APOε2allele carriers, and could allow the emergence of new therapeutic perspectives.

Background: Olfactory dysfunction is a common symptom of many neurodegenerative diseases, and age-related macular degeneration (AMD) is a late-onset neurodegenerative disease. Objective: Thus, the aim of this study was to investigate olfactory functions in patients with AMD. Methods: A total of 69 subjects with AMD and 69 age- and sex-matched healthy controls were enrolled. After a complete ophthalmic evaluation, the AMD patients were subclassified as earlyand late-stage AMD. Psychophysical testing of olfactory function was performed using the validated Sniffin’ Sticks test. Results: This study was carried out in 138 subjects, with a mean age of 74.3 ± 8.9 years (range 51–89). The current investigation showed the following two major findings: (1) patients with AMD had decreased olfactory abilities, especially in odor discrimination and odor identification, even at early stages compared to controls, whereas patients had decreased olfactory abilities in all subtasks of olfactory testings in advanced stages of AMD disease, and (2) as the visual acuity of AMD patients decreased, the olfactory abilities of these patients worsened. Conclusion: This study demonstrated that AMD had significant negative effects on all orthonasal olfactory tasks, particularly in advanced stages. Similar to other neurodegenerative diseases, odor discrimination and identification seemed to be more affected than odor detection threshold tasks.

PURPOSE: Retinal and choroidal ischemic retinopathies such as retinal-vein occlusion (RVO), diabetic retinopathy (DR), and age-related macular degeneration (AMD) are ocular diseases caused by abnormal changes in the microvasculature. The ischemia can lead to macular edema or neovascularization, which can affect vision. Intravitreal injections (IVI) of anti-vascular endothelial growth factor (anti-VEGF) can help to reduce macular edema and improve visual acuity. Lost to follow-up (LTFU) after anti-VEGF injections increases the risk of vision loss in patients with RVO, DR, and AMD. METHODS: Patients scheduled for an IVI of anti-VEGF between September 2009 and September 2019 with either RVO, DR, or AMD were included in the analysis. LTFU was defined as missing an appointment without another evaluation for at least one interval exceeding 180 days. All patients were seen by a single provider at an urban, hospital-based, single-site retina practice in Boston, MA. RESULTS: Among the 698 patients (mean [SD] age, 70.23 [14.2] years; 373 [53.4%] female) identified as receiving an IVI, 121 (17.3%) were LTFU. Age was not found to be statistically different between the LTFU and not LTFU groups (mean difference, -1.67; 95% CI, -4.66¬–1.32; P=.27). Odds of LTFU was lower among patients with AMD (odds ratio [OR], 0.57; 95% CI, 0.36-0.92; P=.02). Odds of LTFU was greater among patients with Medicaid insurance (OR, 2.31; 95% CI, 1.22-4.33; P=.01), compared with patients with Medicare insurance. A trend towards higher risk of LTFU was seen in patients with DR (OR, 1.42; 95% CI, 0.94-2.15; P=.09) and a toward lower risk in patients with two or more eye diseases (OR, 0.53; 95% CI, 0.24-1.15; P=.10). Medicaid insurance was the only significant (P=.02) independent risk factor of LTFU in the multivariate regression. CONCLUSION: We found a high rate of LTFU after anti-VEGF injections among patients with RVO, DR, AMD, and identified risk and protective factors associated with LTFU among this population. Although our results may not be generalizable, data on LTFU in a clinical practice setting are needed to understand the scope of the problem so that interventions may be designed to improve outcomes.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22323号 / 医博第4564号 / 新制||医||1041(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 大森 孝一, 教授 横出 正之, 教授 山下 潤 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Age-related macular degeneration (AMD) is the leading cause for visual impairment in the elderly. The etiology of AMD remains unclear. Clinical and histopathological studies suggest that photoreceptors play a role in disease progression. Here, we found that photoreceptors of AMD patients show adaptive changes in gene expression, suggestive of a nutrient shortage. To study the effect of these changes, we mimicked the metabolic alteration in mouse photoreceptors, by disruption of the Tuberous Sclerosis Complex (TSC). This led to AMD hallmarks, including the advanced stages of geographic atrophy (GA) and choroidal neovascularization (CNV). Furthermore, we found that disease onset requires the activity of the mammalian target of rapamycin complex 1 (mTORC1). To study the contribution of photoreceptors to disease, we profiled retinal phospholipids as photoreceptors are rich in phospholipids. We found a reduction in two docosahexaenoic acid (DHA)-containing phospholipids. Feeding DHA to mutant mice, alleviated most AMD-associated hallmarks. To study the inflammatory complications seen with current anti-vascular endothelial growth factor (VEGF) treatments for CNV we used rAAV-mediated gene transfer to overexpress an anti-VEGF protein. We found that inhibition of VEGF can promote retinal inflammation. The data suggests that targeting photoreceptor metabolism may provide novel therapies to treat AMD.