The impact of lutein-loaded poly(lactic-co-glycolic acid) nanoparticles following topical application: An in vitro and in vivo study.

Antioxidant therapies are of interest in the prevention and management of ocular disorders such as cataracts. Although an active area of interest, topical therapy with antioxidants for the treatment of cataracts is complicated by multiple ocular anatomical barriers, product stability, and solubility. Entrapment and delivery of antioxidants with poly(lactic-co-glycolic acid) nanoparticles is a possible solution to these challenges, however, little is known regarding their effects in vitro or in vivo. Our first aim was to investigate the impact of blank and lutein loaded PLGA nanoparticles on viability and development of reactive oxygen species in lens epithelial cells in vitro. Photo-oxidative stress was induced by ultraviolet light exposure with cell viability and reactive oxygen species monitored. Next, an in vivo, selenite model was utilized to induce cataract formation in rodents. Eyes were treated topically with both free lutein and lutein loaded nanoparticles (LNP) at varying concentrations. Eyes were monitored for the development of anterior segment changes and cataract formation. The ability of nanodelivered lutein to reach the anterior segment of the eye was evaluated by liquid chromatography coupled to mass spectrometry of aqueous humor samples and liquid chromatography coupled to tandem mass spectrometry (targeted LC-MS/MS) of lenses. LNP had a minimal impact on the viability of lens epithelial cells during the short exposure timeframe (24 h) and at concentrations < 0.2 µg LNP/µl. A significant reduction in the development of reactive oxygen species was also noted. Animals treated with LNPs at an equivalent lutein concentration of 1,278 µg /mL showed the greatest reduction in cataract scores. Lutein delivery to the anterior segment was confirmed through evaluation of aqueous humor and lens sample evaluation. Topical treatment was not associated with the development of secondary keratitis or anterior uveitis when applied once daily for one week. LNPs may be an effective in the treatment of cataracts.

Protein profile of purified plasma- and aqueous humor-derived extracellular vesicles from patients with ocular toxoplasmosis.

PURPOSE: To characterize the extracellular vesicle protein cargo in the aqueous humor and plasma of patients with ocular toxoplasmosis. METHODS: Aqueous humor and plasma were collected from six patients with active ocular toxoplasmosis and six patients with cataract. Extracellular vesicles were isolated, and western blotting and mass spectrometry were performed for protein analysis. RESULTS: All plasma samples from patients with ocular toxoplasmosis and cataract were positive for the tetraspanins CD63 and TSG101. However, the aqueous humor from patients with ocular toxoplasmosis was positive only for CD63. Sixty-seven new unreported proteins were identified in the aqueous humor and plasma of patients with the ocular toxoplasmosis and cataract. Of the 67 proteins, 10 and 7 were found only in the cataract and ocular toxoplasmosis groups, respectively. In general, these proteins were involved in immune system activation and retina homeostasis and were related to infections and retina-associated diseases. CONCLUSION: The distinct protein signatures between ocular toxoplasmosis and cataract may be helpful in the differential diagnosis of ocular toxoplasmosis. However, more studies are needed to better understand the role of these proteins in the pathogenesis of ocular toxoplasmosis.

Utilization of multiplex polymerase chain reaction for simultaneous and rapid detection of viral infections from different ocular structures.

The impact of viral keratitis (VK) on individuals and society is notable. Early diagnosis and treatment are crucial in managing viral keratitis effectively. Timely intervention with antiviral medications and supportive care can help mitigate the severity of the infection and improve visual outcomes. We examined the prevalence of varicella-zoster virus (VZV), herpes simplex virus type 1 (HSV-1), adenovirus (AdV) and herpes simplex virus type 2 (HSV-2) in patients suspected for ocular infections. Patients included in the study exhibited various clinical manifestations indicative of ocular pathology, such as infectious keratitis, corneal scar, endogenous endophthalmitis, panuveitis, endothelitis, stromal edema, and other relevant conditions. Four different types of tear fluid, corneal samples epithelium, aqueous humor and vitreous humor were taken. After genome extraction, multiplex real-time PCR was used for diagnosis of viruses. 48 (29.6%) out of the total of 162 (100%) eye specimen were positive. The dominant prevalence was VZV (12.3%) and HSV-1 (11.7%) followed by AdV (4.9%) and HSV-2 (0.6%). There were 4 (8.3%) coinfections within the samples (HSV-1 and VZV). Aqueous humor samples demonstrated superior virus detection ability and our only HSV-2 positive sample was from aqueous humor. The utilization of multiplex real-time PCR assays in differential diagnosis of VK holds promise for expeditious diagnoses while also preventing unwarranted antibiotic prescriptions. Moreover, the aqueous humor appears to be a more sensitive site for detecting viral keratitis.

Ocular and Serum Profiles of Inflammatory Molecules Associated With Retinitis Pigmentosa.

Purpose: To investigate the profiles and correlations between local and systemic inflammatory molecules in patients with retinitis pigmentosa (RP). Methods: The paired samples of aqueous humor and serum were collected from 36 eyes of 36 typical patients with RP and 25 eyes of age-matched patients with cataracts. The concentration of cytokines/chemokines was evaluated by a multiplexed immunoarray (Q-Plex). The correlations between ocular and serum inflammatory molecules and their association with visual function were analyzed. Results: The aqueous levels of IL-6, Eotaxin, GROα, I-309, IL-8, IP-10, MCP-1, MCP-2, RANTES, and TARC were significantly elevated in patients with RP compared to controls (all P < 0.05). The detection rate of aqueous IL-23 was higher in patients with RP (27.8%) compared with controls (0%). In patients with RP, Spearman correlation test demonstrated positive correlations for IL-23, I-309, IL-8, and RANTES between aqueous and serum expression levels (IL-23: ⍴ = 0.8604, P < 0.0001; I-309: ρ = 0.4172, P = 0.0113; IL-8: ρ = 0.3325, P = 0.0476; RANTES: ρ = 0.6685, P < 0.0001). In addition, higher aqueous IL-23 was associated with faster visual acuity loss in 10 patients with RP with detected aqueous IL-23 (ρ = 0.4119 and P = 0.0264). Multiple factor analysis confirmed that aqueous and serum IL-23 were associated with visual acuity loss in patients with RP. Conclusions: These findings suggest that ocular and systemic inflammatory responses have a close interaction in patients with RP. Further longitudinal studies with larger cohorts are needed to explore the correlation between specific inflammatory pathways and the progression of RP. Translational Relevance: This study demonstrates the local-systemic interaction of immune responses in patients with RP.

Aqueous humor cytokine levels in patients with subretinal fibrosis in neovascular age-related macular degeneration.

PURPOSE: To investigate aqueous humor cytokine levels in neovascular age-related macular degeneration (nAMD) patients with subretinal fibrosis and to explore the relationship between cytokine levels and disease severity. METHODS: The aqueous humor samples were collected from 16 eyes with subretinal fibrosis due to nAMD (SRFi group), 33 eyes with nAMD without subretinal fibrosis (nAMD group) and 28 eyes with cataract patients (control group). Clinical samples were analyzed for 5 cytokines,including vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), basic fibroblast growth factor (bFGF), transforming growth factor-α (TGF-α), platelet-derived growth factor-BB (PDGF-BB). RESULTS: Aqueous humor cytokines VEGF and bFGF were significantly higher in nAMD patients than controls (all P < 0.05), and VEGF, bFGF and TGF-α levels were significantly higher in SRFi patients than controls (all P < 0.05). No significant differences in 4 cytokine levels were observed between nAMD and SRFi patients in aqueous humor. We also identified a positive correlation between the aqueous humor levels of IL-6 and VEGF in the SRFi group, while bFGF and TGF-α in the nAMD group. Moreover, VEGF levels were strongly related to BCVA, and bFGF levels were positively related to the maximum thickness of subretinal hyperreflective material (SHRM) in fibrosis due to nAMD. CONCLUSION: VEGF and bFGF levels in aqueous humor were elevated in macular neovascularization with and without subretinal fibrosis. TGF-α levels exclusively differed in neovascular AMD with fibrosis. Cytokines are distributed differently and play a synergistic role in different stages (angiogenesis and fibrogenesis) of nAMD. The bFGF levels could predict the negative prognosis in fibrosis due to nAMD.

Molecular Responses of Anti-VEGF Therapy in Neovascular Age-Related Macular Degeneration: Integrative Insights From Multi-Omics and Clinical Imaging.

Purpose: The purpose of this study was to investigate the molecular mechanisms underlying anti-vascular endothelial growth factor (anti-VEGF) efficacy and response variability in neovascular age-related macular degeneration (nAMD) using longitudinal proteomic and metabolomic analysis alongside three-dimensional lesion measurements. Methods: In this prospective study, 54 treatment-naive patients with nAMD underwent "3+ pro re nata" (3+PRN) anti-VEGF regimens followed for at least 12 weeks. Aqueous humors were collected pre- and post-treatment for proteomic and metabolomic analysis. Three-dimensional optical coherence tomography (OCT) and OCT angiography assessed different types of nAMD lesion volumes and areas. Results: There were 1350 proteins and 1268 metabolites that were identified in aqueous humors, with 301 proteins and 353 metabolites significantly altered during anti-VEGF treatment, enriched in pathways of angiogenesis, energy metabolism, signal transduction, and neurofunctional regulation. Sixty-seven changes of (Δ) molecules significantly correlated with at least one type of ΔnAMD lesion. Notably, proteins FGA, TALDO1, and ASPH significantly decreased during treatment, with their reductions correlating with greater lesion regression in at least two lesion types. Conversely, despite that YIPF3 also showed significant downregulation, its decrease was associated with poorer regression in total nAMD lesion and subretinal hyper-reflective material. Conclusions: This study identifies FGA, TALDO1, and ASPH as potential key molecules in the efficacy of anti-VEGF therapy, whereas YIPF3 may be a key factor in poor response. The integration of longitudinal three-dimensional lesion analysis with multi-omics provides valuable insights into the mechanisms and response variability of anti-VEGF treatment in nAMD.

CRISPR-CasRx-mediated disruption of Aqp1/Adrb2/Rock1/Rock2 genes reduces intraocular pressure and retinal ganglion cell damage in mice.

Glaucoma affects approximately 80 million individuals worldwide, a condition for which current treatment options are inadequate. The primary risk factor for glaucoma is elevated intraocular pressure. Intraocular pressure is determined by the balance between the secretion and outflow of aqueous humor. Here we show that using the RNA interference tool CasRx based on shH10 adenovirus-associated virus can reduce the expression of the aqueous humor circulation related genes Rock1 and Rock2, as well as aquaporin 1 and ß2 adrenergic receptor in female mice. This significantly reduced intraocular pressure in female mice and provided protection to the retina ganglion cells, ultimately delaying disease progression. In addition, we elucidated the mechanisms by which the knockdown of Rock1 and Rock2, or aquaporin 1 and ß2 adrenergic receptor in female mice, reduces the intraocular pressure and secures the retina ganglion cells by single-cell sequencing.

Endothelin-1 Plasma and Aqueous Humor Levels in Different Types of Glaucoma: A Systematic Review and Meta-Analysis.

Background and Objectives: Several studies suggest the complex relationship between Endothelin-1 (ET-1) levels with various types of glaucoma. This systematic review and meta-analysis explore ET-1 levels in plasma and aqueous humor among different types of glaucoma. Materials and Methods: A literature search (PubMed, ScienceDirect, Cochrane Library) was made up to April 2024 (PROSPERO: CRD42023430471). The results were synthesized according to PRISMA Guidelines. Results were presented as standardized mean differences (SMD) with 95% confidence intervals (CI). Results: A total of 2597 subjects (1513 patients with glaucoma vs. 1084 healthy controls) from 23 studies were included in a meta-analysis. Notably, patients with glaucoma reported significantly higher plasma levels of ET-1 compared to controls (SMD: 1.21, 95% CI: 0.59-1.82, p < 0.001). Particularly, plasma ET-1 levels were higher in primary open-angle glaucoma (POAG) (SMD: 0.87, 95% CI: 0.09-1.65, p < 0.05), normal-tension glaucoma (SMD: 0.86, 95% CI: 0.27-1.46, p = 0.05), and angle-closure glaucoma patients (SMD: 1.03, 95% CI: 0.43-1.63, p < 0.001) compared to healthy controls. Moreover, ET-1 aqueous humor levels were significantly higher in patients with glaucoma compared to controls (SMD: 1.60, 95% CI: 1.04-2.15, p < 0.001). In particular, aqueous humor levels were higher in POAG patients (SMD: 2.03 95% CI: 1.00-3.14, p < 0.001), and pseudoexfoliative glaucoma patients (SMD: 2.03, 95% CI: 1.00-3.07, p < 0.001) compared to controls. Conclusions: This meta-analysis indicates that elevated levels of ET-1 plasma and aqueous humor are significantly associated with different types of glaucoma. The pathogenesis of ET-1-related mechanisms may vary across different glaucoma types, indicating that possible therapeutic approaches targeting ET-1 pathways should be tailored to each specific glaucoma type.

Proteomics Analyses of Small Extracellular Vesicles of Aqueous Humor: Identification and Validation of GAS6 and SPP1 as Glaucoma Markers.

Cataracts and glaucoma account for a high percentage of vision loss and blindness worldwide. Small extracellular vesicles (sEVs) are released into different body fluids, including the eye's aqueous humor. Information about their proteome content and characterization in ocular pathologies is not yet well established. In this study, aqueous humor sEVs from healthy individuals, cataracts, and glaucoma patients were studied, and their specific protein profiles were characterized. Moreover, the potential of identified proteins as diagnostic glaucoma biomarkers was evaluated. The protein content of sEVs from patients' aqueous humor with cataracts and glaucoma compared to healthy individuals was analyzed by quantitative proteomics. Validation was performed by western blot (WB) and ELISA. A total of 828 peptides and 192 proteins were identified and quantified. After data analysis with the R program, 8 significantly dysregulated proteins from aqueous humor sEVs in cataracts and 16 in glaucoma showed an expression ratio ≥ 1.5. By WB and ELISA using directly aqueous humor samples, the dysregulation of 9 proteins was mostly confirmed. Importantly, GAS6 and SPP1 showed high diagnostic ability of glaucoma, which in combination allowed for discriminating glaucoma patients from control individuals with an area under the curve of 76.1% and a sensitivity of 65.6% and a specificity of 87.7%.

Green and sensitive detection of olopatadine in aqueous humor using a signal-on fluorimetric approach: GREEnness assessment.

Olopatadine (OLP) is widely utilized as an effective antihistaminic drug for alleviating ocular itching associated with allergic conjunctivitis. With its frequent usage in pharmacies, there arises a pressing need for a cost-effective, easily implementable, environmentally sustainable detection method with high sensitivity. This study presents a novel signal-on fluorimetric method for detecting OLP in both its pure form and aqueous humor. The proposed approach depends on enhancing the weak intrinsic fluorescence emission of OLP, achieving a remarkable increase of up to 680% compared to its intrinsic fluorescence. This enhancement is achieved by forming micelles around protonated OLP using an acetate buffer (pH 3.6) and incorporating a solution of sodium dodecyl sulfate (SDS) surfactant. A strong correlation (R = 0.9996) is observed between the concentration of OLP and fluorescence intensities ranging from 1.0 to 100.0 ng mL-1 with a limit of detection of 0.22 ng mL-1. This described method is successfully employed for quantifying OLP in both its powder form and pharmaceutical eye drops. Furthermore, it demonstrates robust performance in determining OLP in artificial aqueous humor with a percentage recovery of 99.05 ± 1.51, with minimal interference from matrix interferents. Moreover, the greenness of the described method was evaluated.

Pigment Dispersion Contributes to Ocular Immune Privilege in a DBA/2J Mouse Model of Pigmentary Glaucoma.

Purpose: To investigate the effects of anterior chamber pigment dispersion on ocular immune privilege and the possible mechanisms involved in a DBA/2J mouse model of pigmentary glaucoma. Methods: DBA/2J mice were utilized as a pigment dispersion model, and age-matched C57BL/6J mice were used as the control group in this study. Proteins in the aqueous humor (AH) and serum were quantified using the bicinchoninic acid assay. Immune cells in the AH were detected using hematoxylin and eosin staining and immunocytochemistry. The expression of TGF-ß2 in the AH and cytokine levels (IL-10, IFN-γ) in serum were measured using ELISA. Anterior chamber-associated immune deviation (ACAID) was induced in DBA/2J mice by injecting antigens into the anterior chamber. Delayed-type hypersensitivity (DTH) assays were used to assess the induction of ACAID. In DBA/2J mice, before and after pigment dispersion, following anterior chamber injection of pigment particles, and after ACAID modeling, the expression of regulatory T cells (Tregs) was detected using flow cytometry. Results: Compared to C57BL/6J mice, the protein concentration, immune cell count, and TGF-ß2 levels in the AH were elevated in DBA/2J mice. Protein concentration and IL-10 levels in serum were increased, while IFN-γ levels were decreased in DBA/2J. Additionally, the expression of Treg cells in the spleen of DBA/2J mice was significantly increased after pigment dispersion and anterior chamber injection of pigment particles. At 3 and 6 months, DTH responses in DBA/2J mice were not inhibited, thus preventing ACAID induction. However, the opposite was observed at 9 months in DBA/2J mice. Furthermore, the ACAID group exhibited an augmented expression of Treg cells. Conclusions: Dispersion of pigment particles in the anterior chamber of the eye enhances the state of ocular immune privilege by influencing the immunosuppressive microenvironment and inducing more Treg cells to reestablish ACAID.

Analysis of Sphingosine and Sphinganine from the Aqueous Humor for Signaling Studies Using Ultrahigh-Performance Liquid Chromatography-Mass Spectrometry.

Sphingolipids, including sphingosine and sphinganine, are one of the major classes of lipids. They serve as constituents of cell membranes and lipid rafts and aid in the performance of cell-cell communication and adhesion. Abnormal levels of sphingolipids in the aqueous humor can indicate impaired sphingolipid metabolism and associated ocular pathologies. Sphingolipids can be extracted from the aqueous humor by the methyl-tert-butyl ether (MTBE) lipid extraction method and subsequently analyzed by liquid chromatography-mass spectrometry (LC-MS). This chapter describes a modified protocol for an MTBE lipid extraction from the aqueous humor, followed by analysis with ultrahigh-performance liquid chromatography-mass spectrometry (UHPLC-MS).

Levels of asymmetric dimethylarginine in plasma and aqueous humor: a key risk factor for the severity of fibrovascular proliferation in proliferative diabetic retinopathy.

Introduction: Proliferative diabetic retinopathy (PDR) is a common diabetes complication, significantly impacting vision and quality of life. Previous studies have suggested a potential link between arginine pathway metabolites and diabetic retinopathy (DR). Connective tissue growth factor (CTGF) plays a role in the occurrence and development of fibrovascular proliferation (FVP) in PDR patients. However, the relationship between arginine pathway metabolites and FVP in PDR remains undefined. This study aimed to explore the correlation between four arginine pathway metabolites (arginine, asymmetric dimethylarginine[ADMA], ornithine, and citrulline) and the severity of FVP in PDR patients. Methods: In this study, plasma and aqueous humor samples were respectively collected from 30 patients with age-related cataracts without diabetes mellitus (DM) and from 85 PDR patients. The PDR patients were categorized as mild-to-moderate or severe based on the severity of fundal FVP. The study used Kruskal-Wallis test to compare arginine, ADMA, ornithine, and citrulline levels across three groups. Binary logistic regression identified risk factors for severe PDR. Spearman correlation analysis assessed associations between plasma and aqueous humor metabolite levels, and between ADMA and CTGF levels in aqueous humor among PDR patients. Results: ADMA levels in the aqueous humor were significantly greater in patients with severe PDR than in those with mild-to-moderate PDR(P=0.0004). However, the plasma and aqueous humor levels of arginine, ornithine, and citrulline did not significantly differ between mild-to-moderate PDR patients and severe PDR patients (P>0.05). Binary logistic regression analysis indicated that the plasma (P=0.01) and aqueous humor (P=0.006) ADMA levels in PDR patients were risk factors for severe PDR. Furthermore, significant correlations were found between plasma and aqueous humor ADMA levels (r=0.263, P=0.015) and between aqueous humor ADMA and CTGF levels (r=0.837, P<0.001). Conclusion: Elevated ADMA levels in plasma and aqueous humor positively correlate with the severity of FVP in PDR, indicating ADMA as a risk factor for severe PDR.

Implications of Ocular Confounding Factors for Aqueous Humor Proteomic and Metabolomic Analyses in Retinal Diseases.

Purpose: To assess the impact of ocular confounding factors on aqueous humor (AH) proteomic and metabolomic analyses for retinal disease characterization. Methods: This study recruited 138 subjects (eyes): 102 with neovascular age-related macular degeneration (nAMD), 18 with diabetic macular edema (DME), and 18 with cataract (control group). AH samples underwent analysis using Olink Target 96 proteomics and Metabolon's metabolomics platform Data analysis included correlation, differential abundance, and gene-set analysis. Results: In total, 756 proteins and 408 metabolites were quantified in AH. Total AH protein concentration was notably higher in nAMD (3.2-fold) and DME (4.1-fold) compared to controls. Pseudophakic eyes showed higher total AH protein concentrations than phakic eyes (e.g., 1.6-fold in nAMD) and a specific protein signature indicative of matrix remodeling. Unexpectedly, pupil-dilating drugs containing phenylephrine/tropicamide increased several AH proteins, notably interleukin-6 (5.4-fold in nAMD). Correcting for these factors revealed functionally relevant protein correlation clusters and disease-relevant, differentially abundant proteins across the groups. Metabolomics analysis, for which the relevance of confounder adjustment was less apparent, suggested insufficiently controlled diabetes and chronic hyperglycemia in the DME group. Conclusions: AH protein concentration, pseudophakia, and pupil dilation with phenylephrine/tropicamide are important confounding factors for AH protein analyses. When these factors are considered, AH analyses can more clearly reveal disease-relevant factors. Translational Relevance: Considering AH protein concentration, lens status, and phenylephrine/tropicamide administration as confounders is crucial for accurate interpretation of AH protein data.

Parallel Analysis of Exosomes and Cytokines in Aqueous Humor Samples to Evaluate Biomarkers for Glaucoma.

Recent emerging studies have demonstrated numerous critical roles of exosomes in cell-to-cell signaling. We investigated exosomes in the aqueous humor of glaucoma patients and controls and compared their characteristics with other biomarkers such as cytokines. Glaucoma patients exhibited higher exosome particle counts and smaller sizes compared to controls. Higher exosome density was correlated with more severe visual field loss. Conversely, concentrations of aqueous humor cytokines, particularly PD-L1, were primarily associated with intraocular pressure, and none of the cytokines showed a significant association with visual field damage. This may reflect the characteristics of exosomes, which are advantageous for crossing various biological barriers. Exosomes may contain more information about glaucoma functional damage occurring in the retina or optic nerve head. This highlights the potential importance of exosomes as signaling mediators distinct from other existing molecules.

Uveoscleral Outflow Routes after MicroPulse Laser Therapy for Refractory Glaucoma: An Optical Coherence Tomography Study of the Sclera.

To analyze in vivo scleral changes induced by MicroPulse transscleral laser therapy (MP-TLT) in refractory glaucoma using anterior segment-optical coherence tomography (AS-OCT). Forty-two candidate patients for MP-TLT were consecutively enrolled and underwent AS-OCT at baseline and after six months. MP-TLT success was defined as an intraocular pressure (IOP) reduction by one-third. The main outcome measures were the mean superior (S-), inferior (I-), and total (T-) intra-scleral hypo-reflective space area (MISHA: mm2) and scleral reflectivity (S-SR, I-SR, T-SR; arbitrary scale) as in vivo biomarkers of uveoscleral aqueous humor (AH) outflow. The IOP was the secondary outcome. The relations between the baseline-to-six months differences (D) of DS-MISHA, DI-MISHA, and DT-MISHA and DS-SR, DI-SR, DT-SR, and DIOP, were investigated. At 6 months, the median IOP reduction was 21% in the failures and 38% in the successes. The baseline S-MISHA, I-MISHA, and T-MISHA did not differ between the groups, while S-SR and T-SR were higher in the successes (p < 0.05). At six months, successful and failed MP-TLTs showed a 50% increase in S-MISHA (p < 0.001; p = 0.037), whereas I-SR and T-SR reduced only in the successes (p = 0.002; p = 0.001). When comparing DS-MISHA, DI-MISHA, and DT-MISHA and DS-SR, DI-SR, and DT-SR, there were no significant differences between the groups. In the successful procedures, DIOP was positively correlated with DT-MISHA and DI-MISHA (ρ = 0.438 and ρ = 0.490; p < 0.05). MP-TLT produced potentially advantageous modifications of the sclera in refractory glaucoma. Given the partial correlation between these modifications and post-treatment IOP reduction, our study confirmed that the activation of the uveoscleral AH outflow route could significantly contribute to the IOP lowering after MP-TLT.

Comparative Single Vesicle Analysis of Aqueous Humor Extracellular Vesicles before and after Radiation in Uveal Melanoma Eyes.

Small extracellular vesicles (sEVs) have been shown to promote tumorigenesis, treatment resistance, and metastasis in multiple cancer types; however, sEVs in the aqueous humor (AH) of uveal melanoma (UM) patients have never previously been profiled. In this study, we used single particle analysis to characterize sEV subpopulations in the AH of UM patients by quantifying their size, concentration, and phenotypes based on cell surface markers, specifically the tetraspanin co-expression patterns of CD9, CD63, and CD81. sEVs were analyzed from paired pre- and post-treatment (brachytherapy, a form of radiation) AH samples collected from 19 UM patients. In post-brachytherapy samples, two subpopulations, CD63/81+ and CD9/63/81+ sEVs, were significantly increased. These trends existed even when stratified by tumor location and GEP class 1 and class 2 (albeit not significant for GEP class 2). In this initial report of single vesicle profiling of sEVs in the AH of UM patients, we demonstrated that sEVs can be detected in the AH. We further identified two subpopulations that were increased post-brachytherapy, which may suggest radiation-induced release of these particles, potentially from tumor cells. Further study of the cargo carried by these sEV subpopulations may uncover important biomarkers and insights into tumorigenesis for UM.

Next-Generation Sequencing of the Human Aqueous Humour Microbiome.

The microbiome of the ocular surface has been characterised, but only limited information is available on a possible silent intraocular microbial colonisation in normal eyes. Therefore, we performed next-generation sequencing (NGS) of 16S rDNA genes in the aqueous humour. The aqueous humour was sampled from three patients during cataract surgery. Air swabs, conjunctival swabs from patients as well as from healthy donors served as controls. Following DNA extraction, the V3 and V4 hypervariable regions of the 16S rDNA gene were amplified and sequenced followed by denoising. The resulting Amplicon Sequence Variants were matched to a subset of the Ribosomal Database Project 16S database. The deduced bacterial community was then statistically analysed. The DNA content in all samples was low (0-1.49 ng/µL) but sufficient for analysis. The main phyla in the samples were Acinetobacteria (48%), Proteobacteria (26%), Firmicutes (14%), Acidobacteria (8%), and Bacteroidetes (2%). Patients' conjunctival control samples and anterior chamber fluid showed similar patterns of bacterial species containing many waterborne species. Non-disinfected samples showed a different bacterial spectrum than the air swab samples. The data confirm the existence of an ocular surface microbiome. Meanwhile, a distinct intraocular microbiome was not discernible from the background, suggesting the absence of an intraocular microbiome in normal eyes.

Dysregulated Th17/Treg cell axis is correlated with local and systemic immune response in human intermediate uveitis.

Th17/Treg cell balance is essential for immune homeostasis and when disrupted, is associated with the occurrence and development of inflammation in numerous autoimmune diseases. However, its contribution in pathophysiology of uveitis remains unexplored. In this study, we deciphered the role of Th17/Treg cell balance in autoimmune uveitis subjects. Using flow cytometry, we detected the frequencies and absolute count of both Th17 and Treg cells in the aqueous humor and peripheral blood of patients and healthy controls. Our results for the first time reveal a significant increase (p < 0.01 and p < 0.005) in Th17 population alongside a significant decrease (p < 0.001 and p < 0.003) in Treg cell population in both the aqueous humor and PBMCs of uveitis patients. Further we analyzed the expression of Th17-Treg associated genes and cytokines via qPCR and ELISA respectively. These findings align with our flow cytometry results, as evident by a significant (p < 0.002) up-regulation of IL-17 and a concurrent down regulation of IL-10 at transcriptional levels. Moreover, IL-17A cytokine was found to be substantially high (p < 0.001) and IL-10 (p < 0.02) down regulated in serum. Interestingly, we demonstrated a significant correlation of Th17/Treg cells in aqueous humor with those in peripheral blood. Conclusively, our results suggest the pivotal role of Th17/Treg cell axis in the immuno-pathophysiology of human uveitis. Further we propose the therapeutic potential of targeting this novel axis for ameliorating the disease burden associated with uveitis.