Uveitis: a sight-threatening disease which can impact all systems

Analysis of Serum microRNAs During the Development of Experimental Autoimmune Uveoretinitis in Rats

PURPOSE

To investigate alterations in circulating microRNAs (miRNAs) in the development of experimental autoimmune uveoretinitis (EAU) in rats.

METHODS

Lewis rats were immunized with interphotoreceptor retinoid binding protein (IRBP) peptide (R14) and EAU clinical scores were assessed on day 0 (baseline), and days 7, 14, and 21 after immunization. Total RNA was isolated from serum at the same timepoints and used for microarray analysis.

RESULTS

The clinical score of EAU peaked on day 14 and decreased on day 21. Hierarchical cluster analysis and principal component analysis (PCA) of serum miRNA expression displayed distinctly different miRNA profiles between baseline and days 7, 14, and 21 after immunization. Microarray analysis revealed significantly increased expression of 5 (day 7), 9 (day 14), and 10 (day 21) miRNAs, and significantly decreased expression of 19 (day 7), 20 (day 14), and 19 (day 21) miRNAs compared to baseline. Of note, the expression of miRNA-146a-5p, known to be involved in EAU, and miRNA-150-5p was significantly elevated on days 14 and 21. Bioinformatics analysis revealed that mucin type O-glycan biosynthesis and cell adhesion molecules were major pathways affected during the development of EAU.

CONCLUSIONS

Hierarchical cluster analysis and PCA showed distinctly different miRNA profiles at baseline versus after IRBP immunization. Upregulation of serum miRNA-146a-5p and miRNA-150-5p was observed in the effector and resolution phases of EAU. Analysis of circulating miRNAs may help to delineate systemic epigenetic changes occurring in the development of EAU, and may lead to new insights in our understanding of human uveitis.

Single-cell RNA sequencing indicates AP-1 as a potential therapeutic target for autoimmune uveitis

Autoimmune uveitis (AU) is a sight-threatening eye disease, marked by a complex pathogenesis and limited treatment options. Herein, we conducted single-cell RNA sequencing (scRNA-seq) on the spleen and cervical draining lymph nodes (CDLNs) of both normal and experimental autoimmune uveitis (EAU) mice and found common alterations in celluar composition and transcriptional regulation occurred throughout the EAU process. Moreover, we identified activator protein-1 (AP-1) as a pivotal disease-related molecule in the pathogenesis of EAU. Inhibiting AP-1 alleviated symptoms of EAU and reduced the retina infiltration of T helper 17 cells (Th17) and Th1 cells. Additionally, following treatment with the AP-1 inhibitor, both the spleen and CDLNs showed decreased Th17 and Th1 cell proportions. Meanwhile, in vitro studies revealed that treatment with AP-1 inhibitor reduced the level of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-23 (IL-23), two pivotal molecules implicated in the Th17 cell pathogenicity, during EAU. The adoptive transfer experiment also showed that inhibiting AP-1 in CD4+ T cells suppressed their ability to elicit EAU. Altogether, our study demonstrates that AP-1 might involved in EAU pathogenesis by supporting Th17 cell pathogenicity via the GM-CSF/IL-23 feedback loop. Thus, AP-1 inhibition might be a novel treatment strategy for uveitis.

Integrative immunology identified interferome signatures in uveitis and systemic disease-associated uveitis

Introduction

Uveitis accounts for up to 25% of global legal blindness and involves intraocular inflammation, classifed as infectious or non-infectious. Its complex pathophysiology includes dysregulated cytokines, particularly interferons (IFNs). However, the global signature of type I, II, and III interferon-regulated genes (Interferome) remains largely uncharacterized in uveitis.

Methods

In this study, we conducted an integrative systems biology analysis of blood transcriptome data from 169 non-infectious uveitis patients (56 isolated uveitis, 113 systemic disease-associated uveitis) and 82 healthy controls.

Results

Modular co-expression analysis identified distinct cytokine signaling networks, emphasizing interleukin and interferon pathways. A meta-analysis revealed 110 differentially expressed genes (metaDEGs) in isolated uveitis and 91 in systemic disease-associated uveitis, predominantly linked to immune responses. The Interferome database confirmed a predominance of type I and II IFN signatures in both groups. Pathway enrichment analysis highlighted inflammatory responses, including cytokine production (IL-8, IL1-β, IFN-γ, β, and α) and toll-like receptor signaling (TLR4, TLR7, TLR8, CD180). Principal component analysis emphasized the IFN signature's discriminative power, particularly in systemic disease-associated uveitis. Machine learning identified IFN-associated genes as robust predictors, while linear discriminant analysis pinpointed CCR2, CD180, GAPT, and PTGS2 as key risk factors in isolated uveitis and CA1, SIAH2, and PGS in systemic disease-associated uveitis.

Conclusion

These findings highlight IFN-driven imune dysregulation and potential molecular targets for precision therapies in uveitis.

MiR-30b-5p ameliorates experimental autoimmune uveitis by inhibiting the Atg5/Atg12/Becn1 Axis

CONTEXT

Uveitis is a severe autoimmune eye disease that poses a significant threat to visual health. Autophagy is essential for maintaining cellular homeostasis and becomes dysregulated in autoimmune conditions like uveitis. MicroRNAs (miRNAs) can influence autophagy and apoptosis by targeting autophagy-related genes (Atg).

OBJECTIVE

This study aimed to investigate the role of miR-30b-5p in regulating autophagy-related genes and to explore its therapeutic potential in experimental autoimmune uveitis (EAU).

MATERIALS AND METHODS

EAU was induced and RT(Vega-Tapia et al., 2021 [2]) Profiler PCR Arrays were used to identify significant interactions among Atg genes and their role in uveitic pathogenesis. Both in vitro and in vivo experiments were used to assess the expression of Atg-related genes. Additionally, miR-30b-5p-carrying lentivirus injections were administered, and the levels of Atg5, Atg12, and Becn1 were measured, along with autophagosome formation through electron microscopy. Meanwhile, we also assessed inflammatory markers (i.e., IL-10, IL-17), the Th17/Treg ratio, and apoptosis.

RESULTS

In vitro experiments demonstrated that miR-30b-5p led to decreased expression of Atg5, Atg12, and Becn1, which resulted in a lower number of autophagosomes. In vivo validation confirmed these outcomes, showing reduced mRNA and protein levels of Atg-related molecules and diminished autophagosome formation after the injection of miR-30b-5p. Furthermore, miR-30b-5p exhibited anti-inflammatory effects by increasing IL-10 levels and decreasing IL-17, thereby improving the balance of the Th17/Treg ratio.

CONCLUSION

This study highlights the importance of autophagy in the pathogenesis of uveitis and identifies miR-30b-5p as a regulator of autophagy and inflammation. Targeting miR-30b-5p presents a promising therapeutic approach for treating uveitis.

Human umbilical cord-derived mesenchymal stem/stromal cells via suprachoroidal injection: A novel approach for experimental uveitis treatment

Uveitis is a group of vision-threatening inflammatory diseases, and current treatment options are mainly limited to corticosteroids, which often have side effects and do not address the underlying immune dysregulation. Mesenchymal stem/stromal cells cultivated in vitro have gained attention for their immune-regulating, neurotrophic, and tissue-regenerative properties, making them a promising candidate for treating uveitis. This study investigates the safety and efficacy of human umbilical cord derived mesenchymal stem/stromal cells (HUMSCs) combined with a novel suprachoroidal microinjector for targeted delivery in a rabbit model of experimental uveitis (EU). No significant clinical or histological changes were observed following HUMSCs injection in normal Chinichilla rabbit eyes. In the EU model, treatment with HUMSCs and triamcinolone acetonide (TA) significantly alleviated uveitis symptoms compared to phosphate-buffered saline, with notable improvements in anterior chamber inflammation and vitreous opacity scores. Both treatments also reduced the levels of inflammatory cytokines (TNF-α, VEGF, MIP-1α, IL-17A, bFGF) in the aqueous humor. Histological and immunofluorescence analyses showed decreased inflammatory cell infiltration and microglial activation. Additionally, RNA sequencing revealed that HUMSCs injection downregulated key genes in the Th17 differentiation pathway, which plays a critical role in the pathogenesis of EU. These findings establish the safety and efficacy of suprachoroidal injection of HUMSCs, highlighting their potential as an effective, targeted therapeutic approach for uveitis, with results comparable to TA.

Anterior uveitis for the comprehensive ophthalmologist

Anterior uveitis presents a diagnostic challenge due to its wide array of etiologies and clinical manifestations. This narrative review aims to equip general ophthalmologists with a comprehensive understanding of anterior uveitis epidemiology, diagnosis, and treatment. Particular emphasis is placed on developing a tailored and stepwise strategy, rather than a one-size-fits-all approach, for the workup and treatment of anterior uveitis. Chest radiography and serologic testing for syphilis, human leukocyte antigen B27, and angiotensin-converting enzyme are appropriate routine investigations in cases of severe, bilateral, recurrent, or chronic anterior uveitis. Additional testing should be guided by clinical findings and regional epidemiology, especially when considering expensive and invasive modalities. Investigations that are obtained in the absence of clinical and epidemiologic orientation are of limited utility and incur significant costs to patients and health care systems. Most cases of anatomically isolated anterior uveitis resolve with topical corticosteroids, but some patients require escalation to systemic immunomodulatory therapy (IMT). IMT should be considered in patients who respond poorly to corticosteroids, develop side effects related to corticosteroids that limit their use, require high doses to maintain disease remission, or have concomitant systemic inflammatory disease. Comprehensive ophthalmologists should feel comfortable comanaging patients that require conventional disease-modifying antirheumatic drugs/antimetabolite therapy (i.e., methotrexate, azathioprine, and mycophenolate mofetil) with rheumatologists and providing guidance on ocular dosing. When uveitis quiescence cannot be achieved despite maximally tolerated antimetabolite therapy, patients should be referred to a uveitis specialist for consultation and consideration of IMT escalation. The timing of uveitis referral may depend on local factors specific to health care jurisdictions.

High Body Mass Index is Associated with Lower Adalimumab Serum Levels and Higher Disease Activity in Noninfectious Uveitis

PURPOSE

Adalimumab, a TNF-alpha inhibitor, is the only FDA-approved biologic for non-infectious uveitis (NIU). However, treatment responses vary, potentially due to interindividual pharmacokinetic differences influenced by body mass index (BMI). This study aimed to evaluate the impact of BMI on adalimumab serum trough levels and therapeutic efficacy in patients with NIU.

DESIGN

Cross-sectional, clinical study.

METHODS

Setting: Single-center study. - Study Population: 80 patients with NIU treated with Adalimumab - Observation Procedure: Adalimumab serum trough levels and anti-Adalimumab antibody (AAA) levels were measured. BMI was calculated at treatment initiation, and patients were categorized into normal weight, overweight, obese, and morbidly obese groups. - Main Outcome Measures: The correlation between BMI, adalimumab levels, and clinical response was analyzed using Pearson correlation, chi-square tests, and logistic regression.

RESULTS

Higher BMI was associated with lower adalimumab serum levels and a reduced likelihood of clinical response. A significant negative correlation was found between BMI and adalimumab levels (r = -0.408, P = .007). Logistic regression identified BMI as a significant predictor of treatment response (P = .017). A BMI threshold of 26.4 was identified, above which the probability of a positive response significantly decreased. Additionally, 51.2% of patients were non-responders, all of whom demonstrated detectable AAA.

CONCLUSIONS

Higher BMI is associated with lower adalimumab trough levels and reduced treatment efficacy in NIU patients. A BMI threshold of 26.4 may serve as a clinical marker for tailoring adalimumab therapy, highlighting the need for personalized dosing strategies in patients with elevated BMI.

Epidemiological Characterization of Uveitis in Japan: a Systematic Review

PURPOSE

Study the etiologies, behind uveitis, examine the anatomical location, and explore how these causes vary across regions in Japan.

METHODS

The systemic review was conducted followed the PRISMA guidelines, searching through databases, like PubMed/MEDLINE, Scopus, Central and Web of Science, from January 1990 to August 2024. Our focus was on studies done in Japan. Presented in either English or Japanese and provided information on uveitis etiologies. We excluded any studies using selfreported data during our selection process.

RESULTS

Out of a total of 1,738 studies initially considered, only 20 met the criteria for inclusion. The majority of uveitis cases were categorized as "unclassified." Sarcoidosis was the most common systemic etiology, followed by VogtKoyanagiHarada (VKH), with Behcet's disease coming next. Most studies showed a greater number of female patients. In Tokyo, sarcoidosis accounts for 8.9% of uveitis cases, making it the most systemic association cause. In contrast, in Hokkaido, while sarcoidosis remains the leading systemic association of uveitis, it is significantly more prevalent at 19.5%.

CONCLUSION

The findings reveal significant regional variations in the causes of uveitis across Japan, with sarcoidosis playing a major role. These regional differences underscore the importance of considering local factors in the diagnosis and treatment of uveitis. Additionally, the high prevalence of unclassified uveitis cases points to the urgent need for better methods to accurately identify and manage these conditions.

Nanotechnological approaches to improve corticosteroids ocular therapy

The administration of corticosteroids is the first-line treatment of the clinical conditions with ocular inflammation. Nonetheless, ocular physiological mechanisms, anatomical barriers and corticosteroid properties prevent it from reaching the target site. Thus, frequent topical administered doses or ocular injections are required, leading to a higher risk of adverse events and poor patient compliance. Designing novel drug delivery systems based on nanotechnological tools is a useful approach to overcome disadvantages associated with the ocular delivery of corticosteroids. Nanoparticle-based drug delivery systems represent an alternative to the current dosage forms for the ocular administration of corticosteroids, since due to their particle size and the properties of their materials, they can increase their solubility, improve ocular permeability, control their release and increase bioavailability after their ocular administration. In this way, lipid and polymer-based nanoparticles have been the main strategies developed, giving rise to novel patent applications to protect these innovative drug delivery systems as a product, its preparation or administration method. Additionally, it should be noted that at least 10 clinical trials are being carried out to evaluate the ocular application of different pharmaceutical formulations based on corticosteroid-loaded nanoparticles. Through a comprehensive and extensive analysis, this review highlights the impact of nanotechnology applications in ocular inflammation therapy with corticosteroids.

Exosomes in Ocular Health: Recent Insights into Pathology, Diagnostic Applications and Therapeutic Functions

Exosomes are extracellular vesicles ranging from 30 to 150 nm in diameter that contain proteins, nucleic acids and other molecules. Produced by virtually all cell types, they travel throughout the body until they reach their target, where they can trigger a wide variety of effects by transferring the molecular cargo to recipient cells. In the context of ocular physiology, exosomes play a very important role in embryological development, the regulation of homeostasis and the immune system, which is crucial for normal vision. Consequently, in pathological situations, exosomes also undergo modifications in terms of quantity, composition and content, depending on the etiology of the disease. However, the mechanisms by which exosomes contribute to ocular pathology has not yet been studied in depth, and many questions remain unanswered. This review aims to summarize the most recent knowledge on the function of exosomes in the ocular system in healthy individuals and the role they play during pathological processes of a degenerative, infectious, neurodegenerative, vascular and inflammatory nature, such as keratoconus, keratitis, glaucoma, diabetic retinopathy and uveitis. Furthermore, given their unique characteristics, their potential as diagnostic biomarkers or therapeutic agents and their application in clinical ophthalmology are also explored, along with the main limitations that researchers face today in the field.

Genetic evidence supports the causal effects of exposure to ambient air pollution on autoimmune eye diseases

Previous observational studies have reported inconsistent associations between air pollution and autoimmune eye diseases (AEDs). The primary objective of this Mendelian randomization (MR) study was to investigate the causal link of air pollution with AEDs risk. The instrumental variables were selected based on genome-wide association study data. Univariable and multivariable MR analyses were conducted to disentangle the causality of air pollutants with AEDs. The estimates of univariable MR analysis revealed a suggestively causal link between NO2 or NOx exposure and diabetic retinopathy (OR=1.29, 95% CI=1.05-1.58, P=0.015; OR=1.33, 95% CI=1.05-1.69, P=0.019, respectively). A suggestive association was observed between PM2.5 exposure and age-related macular degeneration (OR=1.46, 95% CI=1.09-1.97, P=0.013). In addition, multivariable MR indicated that the observed association was remained consistent and robust. Rigorous sensitivity analyses confirmed the robustness and consistency of these findings. Our study firstly provided the genetic evidence linking air pollution, specially NO2, NOx and PM2.5, to AEDs susceptibility.

Cytokines in Immune-mediated "Non-infectious" Uveitis

Uveitis is a significant cause of ocular morbidity and accounts for approximately 5 - 10% of visual impairments worldwide, particularly among the working-age population. Infections are the cause of ~ 50% cases of uveitis, but it has been suggested that infection might also be implicated in the pathogenesis of immune-mediated "non-infectious" uveitis. There is growing evidence that cytokines (i.e., interleukins, interferons, etc.) are key mediators of immune-mediated "non-infectious" uveitis. For example, activation of the interleukin-23/interleukin-17 signalling pathway is involved in immune-mediated "non-infectious" uveitis. Studies in animal models have been important in investigating the role of cytokines in uveitis. Recent studies of clinical samples from patients with uveitis have allowed the measurement of a considerable array of cytokines even from very small sample volumes (e.g., aqueous and vitreous humour). The identification of complex patterns of cytokines may contribute to a better understanding of their potential pathogenetic role in uveitis as well as to an improved diagnostic and therapeutic approach to treat these potentially blinding pathologies. This review provides further insights into the putative pathobiological role of cytokines in immune-mediated "non-infectious" uveitis.

Itaconate Ameliorates Experimental Autoimmune Uveitis by Modulating Teff/Treg Cell Imbalance Via the DNAJA1/CDC45 Axis

Purpose

The aim of this study was to elucidate the effect of itaconate (ITA) on experimental autoimmune uveitis (EAU), to explore its potential mechanism, and to identify potential therapeutic targets.

Methods

We established an animal model of EAU by constructing an immune map of mice treated with ITA and exploring the therapeutic mechanism of ITA by single-cell RNA sequencing and flow cytometry.

Results

ITA mitigated ocular inflammation associated with EAU and reversed the pathogenic differentiation linked to Th17 induction by EAU, along with the reactive oxygen species (ROS) and oxidative stress pathways. Subsequent to ITA intervention, the downregulated differentially expressed genes in the T-cell subset primarily centered around the heat shock protein (HSP) family. Activation of HSPs reversed the anti-inflammatory effects of ITA in EAU mice. ITA decreased ROS levels and HSP expression in CD4+ T cells, with DnaJ heat shock protein family (HSP40) member A1 (DNAJA1) exhibiting the most notable alterations among the HSPs. ITA suppressed the expression of DNAJA1/cell division cycle protein 45 (CDC45), thereby disrupting the pathogenic division cycle of CD4+ T cells and reducing their proliferation. Inhibiting DNAJA1 also held promise for modulating the Th17/Treg imbalance. Notably, ITA curtailed the expansion of CD4+ T cells in uveitis patients.

Conclusions

Our research delved into the potential therapeutic mechanisms underlying ITA therapy in EAU, offering fresh perspectives on its utility in the treatment of autoimmune conditions. DNAJA1 emerges as a promising candidate for targeted therapeutic interventions in uveitis.

A Postbiotic Formulation of Lactiplantibacillus plantarum CRL 759 Attenuates Endotoxin Induced Uveitis

PURPOSE

To evaluate the anti-inflammatory activity of a cell-free supernatant from Lactiplantibacillus plantarum CRL 759, in phosphate buffer modified according to Sorensen called POF-759.

METHODS

The activity of POF-759 administered by means of eye drops was evaluated on animals subcutaneously injected with the lipopolysaccharide animals in which uveitis was induced by a subcutaneous injection of lipopolysaccharide (EIU). Clinical signs of ocular inflammation, cytokines and proteins were examined in the aqueous humor. Additionally, cellular infiltration was evaluated by histopathological analysis.

RESULTS

The new postbiotic administered locally decreases signs of ocular damage, the number of infiltrating cells in the anterior and posterior chambers, the proinflammatory mediators and the proteins in the aqueous humor on mice with EIU.

CONCLUSIONS

Our results provide an impetus to relieve ocular inflammation and to identify and develop preventive and therapeutic approaches, to avoid deterioration and to maintain healthy eyes on inflammatory processes.

Fine particulate matter potentiates Th17-cell pathogenicity in experimental autoimmune uveitis via ferroptosis

The effect of fine particulate matter (PM2.5) on the development of uveitis remains unclear. Therefore, this study was designed to investigate the role of PM2.5 in experimental autoimmune uveitis (EAU) and its potential mechanism. Our results showed that PM2.5 could exacerbate the activity of EAU, as evidenced by severer clinical and pathological changes, correlated with elevated Th17 cells frequency and IL-17A expression. Proteomic analysis revealed ferroptosis was the most significant pathway. In vivo, the levels of Fe2+, ROS, lipid ROS, and malondialdehyde, as well as the expression of TFRC, HMOX1, FTH1, and FTL1 in CD4+ T cells were increased, while GSH/GSSG ratio and the expression of ACSL1 and GPX4 were decreased after PM2.5 exposure. In vitro, the expression of TFRC and HMOX1 were increased, while the expression FTH1, FTL1, ACSL1, and GPX4 were decreased after PM2.5 exposure. Ferrostatin-1 effectively alleviated PM2.5-induced intraocular inflammation and suppressed the frequency of Th17 cells. These results suggest that PM2.5 could aggravate intraocular inflammation and immune response in EAU mice through ferroptosis. Ferroptosis could be a potential marker for the prevention and treatment of uveitis.

Irisin Alleviates Autoimmune Uveitis Through Promoting Retinal Microglial M1 to M2 Phenotypic Polarization Mediated by HIF-1α Pathway

Irisin, proteolytically cleaved from Fndc5 protein, has been identified as an exercise-related hormone. Here, we investigated the irisin levels in aqueous humor and its involvement in the pathogenesis of uveitis. The results revealed that the irisin level in the aqueous humor was significantly decreased in Vogt-Koyanagi-Harada (VKH), and Behcet uveitis (BU) patients, and was negatively correlated with TNF-α in BU patients. Exogenous supplementation of irisin alleviated scores of experimental autoimmune uveitis (EAU) clinically and pathologically and suppressed the proportion of Th1 and Th17 cells in spleen. Fndc5-/- EAU mice exhibited more severe inflammatory manifestations with increased microglial activation in the retina. Irisin could mitigate M1 microglia and promote M2 microglia polarization. RNA sequencing of the retina showed that HIF-1α pathway was significantly enriched in Fndc5-/- EAU mice. HIF-1α pathway inhibitor significantly rescued EAU severity, associated with a decreased M1 microglial polarization in the retina of Fndc5-/- mice. In conclusion, we highlighted that irisin could alleviate uveitis by inhibiting Th1 and Th17 cells and reducing M1 microglial polarization via HIF-1α pathway.

Quantitative urinary proteome analysis reveals potential biomarkers for disease activity of Behcet's disease uveitis

PURPOSE

Behçet's disease-associated uveitis (BDU) is a severe, recurrent inflammatory condition affecting the eye and is part of a systemic vasculitis with unknown etiology, making biomarker discovery essential for disease management. In this study, we intend to investigate potential urinary biomarkers to monitor the disease activity of BDU.

METHODS

Firstly, label-free data-dependent acquisition (DDA) and tandem mass tag (TMT)-labeled quantitative proteomics methods were used to profile the proteomes of urine from active and quiescent BDU patients, respectively. For further exploration, the remaining fifty urine samples were analyzed by a data-independent acquisition (DIA) quantitative proteomics method.

RESULTS

Twenty-nine and 21 differential proteins were identified in the same urine from BDU patients by label-free DDA and TMT-labeled analyses, respectively. Seventy-nine differentially expressed proteins (DEPs) were significantly changed in other active BDU urine samples compared to those in quiescent BDU urine samples by IDA analysis. Gene Ontology (GO) and protein-protein interaction (PPI) analyses revealed that the DEPs were associated with multiple functions, including the immune and neutrophil activation responses. Finally, seven proteins were identified as candidate biomarkers for BDU monitoring and recurrence prediction, namely, CD38, KCRB, DPP4, FUCA2, MTPN, S100A8 and S100A9.

CONCLUSIONS

Our results showed that urine can be a good source of biomarkers for BDU. These dysregulated proteins provide potential urinary biomarkers for BDU activity monitoring and provide valuable clues for the analysis of the pathogenic mechanisms of BDU.

High salt diet alleviates disease severity in native experimental autoimmune uveitis

Background

Recent studies reported a link between high salt diet (HSD) and clinical exacerbation in mouse models of autoimmune diseases, mainly through the induction of pathogenic Th17 cells and/or HSD-induced dysbiosis. However, the topic remains controversial and not fully understood.

Purpose

In this study, we investigated the effects of HSD on the development of experimental autoimmune uveitis (EAU) in C57BL/6J mice.

Methods and results

Unexpectedly, our data showed a significant attenuating effect of HSD on disease severity of native EAU, induced by direct immunization with IRBP peptide. That said, HSD had no effect on EAU disease severity induced by adoptive transfer of semi-purified auto-reactive IRBP-specific T lymphocytes. Accordingly, HSD did not affect IRBP-specific systemic afferent immune response as attested by no HSD-linked changes in T lymphocytes proliferation, cytokine production and Treg proportion. Gut microbiota analysis from cecal samples in naïve and EAU mice demonstrated that HSD affected differentially α-diversity between groups, whereas β-diversity was significantly modified in all groups. Unknown Tannerellaceae was the only taxon associated to HSD exposure in all treatment groups. Interestingly, a significantly higher abundance of unknown Gastranaerophilales, with potential anti-inflammatory properties, appeared in HSD-fed native EAU mice, only.

Discussion

In conclusion, our study suggests a possible impact of HSD on gut microbiota composition and consequently on development and clinical severity of EAU. Further studies are required to investigate the potential beneficial role of Gastranaerophilales in EAU.

Clinical Insights: Antimicrobial Therapy for Infectious Uveitis

Infectious uveitis is a major global cause of vision impairment. Despite the eye's immune privilege, afforded by the blood-ocular barrier that restricts microbial entry, several pathogens such as bacteria, viruses, fungi, and parasites can still infiltrate and cause ocular infections and complications. Clinicians often encounter significant challenges in treating infectious uveitis due to limited or ineffective treatment options. Modern molecular techniques and imaging can aid in diagnosing and assessing intraocular infections. Various antimicrobial therapies exist, spanning topical and systemic treatments, but these are constrained by issues like drug concentration, penetration, effective duration, toxicity, and side effects. Treatment approaches also differ based on the infection's etiology. This review provides recent updates on antimicrobial therapies from a clinical perspective, covering topical, systemic, and regional treatments for infectious uveitis.

Obesity, body fat distribution and eye diseases

BACKGROUND

The prevalence of obesity, a chronic disease, is increasing, and obesity is now considered a global epidemic. Eye diseases are also increasing worldwide and have serious repercussions on quality of life as well as increasingly high costs for the community. The relationships between obesity and ocular pathologies are not yet well clarified and are not pathologically homogeneous: they seem to be somehow linked to excess body fat, especially to the distribution of adipose tissue and its ectopic deposits.

PURPOSE

Our objective was to examine the associations between obesity and anthropometric indices, including body mass index (BMI), waist circumference (WC), and the waist/hip ratio (WHR), and the risk of most widespread eye diseases, with particular attention given to the most significant metabolic mechanisms.

METHODS

This article provides a narrative overview of the effect of obesity and anthropometric measurements of body fat on prevalent eye diseases. We used the MEDLINE/PubMed, CINAHL, EMBASE, and Cochrane Library databases from 1984 to 2024. In addition, we hand-searched references from the retrieved articles and explored a number of related websites. A total of 153 publications were considered.

RESULTS

There is significant evidence that obesity is associated with several eye diseases. Waist circumference (WC) and the waist/hip ratio (WHR) have been observed to have stronger positive associations with eye diseases than BMI.

CONCLUSIONS

Obesity must be considered a significant risk factor for eye diseases; hence, a multidisciplinary and multidimensional approach to treating obesity, which also affects ocular health, is important. In the prevention and treatment of eye diseases related to obesity, lifestyle factors, especially diet and physical activity, as well as weight changes, both weight loss and weight gain, should not be overlooked.

LEVEL OF EVIDENCE

Level V narrative review.

New targets of nascent lymphatic vessels in ocular diseases

Recent advancements in the field of endothelial markers of lymphatic vessels and lymphangiogenic factors have shed light on the association between several ocular diseases and ocular nascent lymphatic vessels. The immune privilege of corneal tissue typically limits the formation of lymphatic vessels in a healthy eye. However, vessels in the eyes can potentially undergo lymphangiogenesis and be conditionally activated. It is evident that nascent lymphatic vessels in the eyes contribute to various ocular pathologies. Conversely, lymphatic vessels are present in the corneal limbus, ciliary body, lacrimal glands, optic nerve sheaths, and extraocular muscles, while a lymphatic vasculature-like system exists in the choroid, that can potentially cause several ocular pathologies. Moreover, numerous studies indicate that many ocular diseases can influence or activate nascent lymphatic vessels, ultimately affecting patient prognosis. By understanding the mechanisms underlying the onset, development, and regression of ocular nascent lymphatic vessels, as well as exploring related research on ocular diseases, this article aims to offer novel perspectives for the treatment of such conditions.

The Humira in Ocular Inflammations Taper (HOT) Study

PURPOSE

To assess factors that impact the risk of relapse in patients with noninfectious uveitis (NIU) who undergo adalimumab tapering after achieving remission.

DESIGN

Retrospective study.

METHODS

In this multicenter study, patients with NIU were treated with adalimumab and subsequently tapered. Patient demographics, type of NIU, onset and duration of disease, the period of inactivity before tapering adalimumab, and the tapering schedule were collected. The primary outcome measures were independent predictors of the rate of uveitis recurrence after adalimumab tapering.

RESULTS

Three hundred twenty-eight patients were included (54.6% female) with a mean age of 34.3 years. The mean time between disease onset and initiation of adalimumab therapy was 35.2 ± 70.1 weeks. Adalimumab tapering was commenced after a mean of 100.8 ± 69.7 weeks of inactivity. Recurrence was observed in 39.6% of patients at a mean of 44.7 ± 61.7 weeks. Patients who experienced recurrence were significantly younger than those without recurrence (mean 29.4 years vs 37.5 years, P = .0005), and the rate of recurrence was significantly higher in younger subjects (hazard ratio [HR] = 0.88 per decade of increasing age, P = .01). The lowest rate of recurrence was among Asian subjects. A faster adalimumab taper was associated with an increased recurrence rate (HR = 1.23 per unit increase in speed, P < .0005). Conversely, a more extended period of remission before tapering was associated with a lower rate of recurrence (HR = 0.97 per 10-weeks longer period of inactivity, P = .04).

CONCLUSIONS

When tapering adalimumab, factors that should be considered include patient age, race, and duration of disease remission on adalimumab. A slow tapering schedule is advisable.

Unveiling the Web: Exploring the Multifaceted Role of Neutrophil Extracellular Traps in Ocular Health and Disease

Neutrophil extracellular traps (NETs) play an essential role in antimicrobial defense. However, NETs have also been shown to promote and mediate a wide spectrum of diseases, including cancer, diabetes mellitus, cardiovascular diseases, and ocular diseases. Data regarding NETs in ocular diseases remain limited. In physiological conditions, NETs protect the eye from debris and cleave proinflammatory cytokines, including several interleukins. On the other hand, NETs play a role in corneal diseases, such as dry eye disease and ocular graft-versus-host disease, where they promote acinar atrophy and delayed wound healing. Additionally, NET levels positively correlate with increased severity of uveitis. NETs have also been described in the context of diabetic retinopathy. Although increased NET biomarkers are associated with an increased risk of the disease, NETs also assist in the elimination of pathological blood vessels and the regeneration of normal vessels. Targeting NET pathways for the treatment of ocular diseases has shown promising outcomes; however, more studies are still needed in this regard. In this article, we summarize the literature on the protective roles of NETs in the eye. Then, we describe their pathogenetic effects in ocular diseases, including those of the cornea, uvea, and retinal blood vessels. Finally, we describe the therapeutic implications of targeting NETs in such conditions.

Serum amyloid A aggravates endotoxin-induced ocular inflammation through the regulation of retinal microglial activation

Serum amyloid A (SAA) are major acute-phase response proteins which actively participate in many inflammatory diseases. This study was designed to explore the function of SAA in acute ocular inflammation and the underlying mechanism. We found that SAA3 was upregulated in endotoxin-induced uveitis (EIU) mouse model, and it was primarily expressed in microglia. Recombinant SAA protein augmented intraocular inflammation in EIU, while the inhibition of Saa3 by siRNA effectively alleviated the inflammatory responses and rescued the retina from EIU-induced structural and functional damage. Further study showed that the recombinant SAA protein activated microglia, causing characteristic morphological changes and driving them further to pro-inflammatory status. The downregulation of Saa3 halted the amoeboid change of microglia, reduced the secretion of pro-inflammatory factors, and increased the expression of tissue-reparative genes. SAA3 also regulated the autophagic activity of microglial cells. Finally, we showed that the above effect of SAA on microglial cells was at least partially mediated through the expression and signaling of Toll-like receptor 4 (TLR4). Collectively, our study suggested that microglial cell-expressed SAA could be a potential target in treating acute ocular inflammation.

Differential Proteins Expression Distinguished Between Patients With Infectious and Noninfectious Uveitis

PURPOSE

We investigated the aqueous humor proteome and associated plasma proteome in patients with infectious or noninfectious uveitis.

METHODS

AH and plasma were obtained from 28 patients with infectious uveitis (IU), 29 patients with noninfectious uveitis (NIU) and 35 healthy controls undergoing cataract surgery. The proteins profile was analyzed by SomaScan technology.

RESULTS

We found 1844 and 2484 proteins up-regulated and 124 and 161 proteins down-regulated in the AH from IU and NIU groups, respectively. In the plasma, three proteins were up-regulated in NIU patients, and one and five proteins were down-regulated in the IU and NIU patients, respectively. The results of pathway enrichment analysis for both IU and NIU groups were related mostly to inflammatory and regulatory processes.

CONCLUSION

SomaScan was able to detect novel AH and plasma protein biomarkers in IU and NIU patients. Also, the unique proteins found in both AH and plasma suggest a protein signature that could distinguish between infectious and noninfectious uveitis.

Novel Role of Molecular Hydrogen: The End of Ophthalmic Diseases?

Molecular hydrogen (H2) is a colorless, odorless, and tasteless gas which displays non-toxic features at high concentrations. H2 can alleviate oxidative damage, reduce inflammatory reactions and inhibit apoptosis cascades, thereby inducing protective and repairing effects on cells. H2 can be transported into the body in the form of H2 gas, hydrogen-rich water (HRW), hydrogen-rich saline (HRS) or H2 produced by intestinal bacteria. Accumulating evidence suggest that H2 is protective against multiple ophthalmic diseases, including cataracts, dry eye disease, diabetic retinopathy (DR) and other fields. In particular, H2 has been tested in the treatment of dry eye disease and corneal endothelial injury in clinical practice. This medical gas has brought hope to patients suffering from blindness. Although H2 has demonstrated promising therapeutic potentials and broad application prospects, further large-scale studies involving more patients are still needed to determine its optimal application mode and dosage. In this paper, we have reviewed the basic characteristics of H2, and its therapeutic effects in ophthalmic diseases. We also focus on the latest progress in the administration approaches and mechanisms underlying these benefits.

Pattern of Uveitis at a Tertiary Eye Hospital in Eastern Province of Saudi Arabia and Comparison with Local Literature

PURPOSE

To explore the patterns of uveitis in a main ophthalmic referral center in the Eastern province of Saudi Arabia.

METHODS

A retrospective chart review of uveitis cases was conducted in a tertiary eye hospital for five years. In addition, a comprehensive review of Saudi publications about uveitis patterns in the literature.

RESULTS

Out of 222 patients included, 54.4% were females, with a mean age of 38.5 years. Uveitis was bilateral in 55.7%, non-granulomatous in 55.9%, and infectious in 11.3%. Most of the cases were anterior uveitis (51.1%), followed by panuveitis (26%), intermediate uveitis (12.8%), and posterior uveitis (10%). Apart from idiopathic cases (43.7%), the most common diagnoses were Vogt-Koyanagi-Harada disease (11.3%) and Behcet's disease (7.7%) in adults. Juvenile idiopathic arthritis (7.2%) was commonest among children. Posterior synechiae was the leading complication (32.0%), followed by cataracts (22.8%).

CONCLUSIONS

VKH and Behçet disease were the primary non-idiopathic etiologies in Saudi Arabia.

The large Hellenic Study of Uveitis: epidemiology, etiologic factors and classification

PURPOSE

To analyse the demography, etiology, and classification of uveitis at a tertiary academic referral center.

METHODS

An observational study was conducted on the archives of uveitic patients at the Ocular Inflammation Service of the Department of Ophthalmology at the University Hospital of Ioannina (Greece) from 1991 to 2020. This study aimed to investigate the epidemiological profile of patients, including their demographics and the main etiologic factors of uveitis.

RESULTS

Out of 6191 cases with uveitis, 1925 were infectious, 4125 were non-infectious, and an overall of 141 masquerade syndromes were recorded. Among these cases, 5950 patients were adults, with a slight female predominance, while 241 were children (< 18 years old). Interestingly, 24.2% of cases (1500 patients) were associated with 4 specific microorganisms. Herpetic uveitis (HSV-1 and VZV/HZV) was the most common cause of infectious uveitis (14.87%), followed by toxoplasmosis (6.6%) and tuberculosis (2.74%). In 49.2% of non-infectious uveitis cases, no systematic correlation was found. The most frequent causes of non-infectious uveitis included sarcoidosis, white dot syndromes, ankylosing spondylitis, lens-induced uveitis, Adamantiades-Behçet disease, and idiopathic juvenile arthritis. Infectious uveitis was more common in the rural population, whereas non-infectious uveitis was more frequently recorded in the urban population CONCLUSIONS: Although our study was conducted on a predominantly white Caucasian population, it also reflects the effect of increasing immigration, improvements of diagnostic techniques, changes in referral patterns, and various actual changes in disease incidence.

A novel peptide derived from the mannose binding lectin inhibits LPS-activated TLR4/NF-κB signaling and suppresses ocular inflammation

Uveitis is a major cause of vision impairment worldwide. Current treatments have limited effectiveness but severe complications. Mannose binding lectin (MBL) is an important protein of the innate immune system that binds to TLR4 and suppresses LPS-induced inflammatory cytokine secretion. MBL-mediated inhibition of inflammation via the TLR4 pathway and MBL-derived peptides might be a potential therapeutics. In this study, we designed a novel MBL-derived peptide, WP-17, targeting TLR4. Bioinformatics analysis was conducted for the sequence, structure and biological properties of WP-17. The binding of WP-17 to THP-1 cells was analyzed using flow cytometry. Signaling molecules were analyzed by western blotting, and activation of NF-κB was measured by immunofluorescence-histochemical analysis. Effects of WP-17 were studied in vitro using LPS-stimulated THP-1 cells and in vivo in endotoxin-induced uveitis (EIU). Our results showed that WP-17 could bind to TLR4 expressed on macrophages, thus downregulating the expression levels of MyD88, IRAK-4, and TRAF-6, and inhibiting the downstream NF-kB signaling pathway and LPS-induced expression of TNF-α and IL-6 in THP-1 cells. Moreover, in EIU rats, intravitreal pretreatment with WP-17 demonstrated significant inhibitory effects on ocular inflammation, attenuating the clinical and histopathological manifestations of uveitis, reducing protein leakage and cell infiltration into the aqueous humor, and suppressing TNF-α and IL-6 production in ocular tissues. In summary, our study provides the first evidence of a novel MBL-derived peptide that suppressed activation of the NF-кB pathway by targeting TLR4. The peptide effectively inhibited rat uveitis and may be a promising candidate for the management of ocular inflammatory diseases.

Uveitis: Study of 109 cases

PURPOSE

Analyse and describe the anatomical and etiological classification, clinical and epidemiological characteristics and most frequent symptoms of uveitis cases in our population.

PATIENTS AND METHOD

Descriptive, retrospective observational study of uveitis cases treated in the Ophthalmology Department of Virgen del Rocío University Hospital in 2021. The demographic and clinical characteristics were studied.

RESULTS

A total of 109cases of uveitis were studied, 46 men and 63 women, with a mean age of 45.43±16.11 years. The most frequent symptoms were pain (74.31%), hyperemia (73.39%) and blurred vision (65.14%). The most frequent anatomical classification was anterior (55.96%), followed by panuveitis (18.35%), posterior (12.84%) and intermediate uveitis (7.34%). Regarding etiology, most uveitis were idiopathic (42.99%), followed by non-infectious (38.32%) and finally infectious (18.69%).

CONCLUSIONS

In southern España, the characteristics of uveitis are similar to other studies in Western countries.

Diagnosis of tuberculous uveitis by the macrogenome of intraocular fluid: A case report and review of the literature

BACKGROUND

Tuberculous uveitis caused by tuberculosis infection factors is common, but tuberculous uveitis caused by Mycobacterium tuberculosis found in the intraocular fluid is rare. This report describes the use of intraocular fluid in the diagnosis of tuberculous uveitis in a patient and reviews the relevant literature.

CASE SUMMARY

A 24-year-old woman who was 31-wk pregnant visited Hebei Chest Hospital due to intermittent chest pain, fever, and decreased vision for 3 mo. The hydrothorax test suggested “tuberculous pleurisy”, and yellow effusion was extracted from the chest tube twice resulting in a total volume of approximately 800 mL. The patient chose to continue the pregnancy without treatment, and was hospitalized again due to high fever. Following 2 mo of anti-tuberculosis treatment, a healthy boy was delivered by cesarean section. Tuberculous uveitis was diagnosed using tuberculosis Xpert, and intraocular infection was detected by second-generation gene sequencing. Following systemic treatment, the patient gradually improved, and the corrected visual acuity of the left eye gradually increased from 0.08 to 1.0.

CONCLUSION

The etiology of uveitis is complex, and it is necessary to assess the patient’s general condition and apply molecular biology methods to determine the pathogenesis and guide precise treatment, to improve clinicians’ awareness and standardize treatment of the disease.

Evaluation of uveitis events in real-world patients receiving immune checkpoint inhibitors based on the FAERS database

PURPOSE

Immune checkpoint inhibitors (ICIs) have emerged as a novel class of drugs carrying a potential risk of uveitis. Due to the rarity, current knowledge on this safety issue is still incomplete. This study employed the post-marketing surveillance data to comprehensively describe and assess the uveitis events after the use of ICIs.

METHODS

Data between 2004 and 2021 were downloaded from the Food and Drug Administration Adverse Event Reporting System (FAERS), and the uveitis events reported for ICIs were identified and included in this study. Clinical details of these reports were collected and analyzed. Four data mining methods were utilized to investigate the potential associations between uveitis and different ICI regimens.

RESULTS

Overall, 461 uveitis cases after exposure to ICI therapies were reported. Melanoma (58.79%) was revealed as the most common indication for receiving ICIs. The median onset time of uveitis was 41 (interquartile range 18-91) days after ICI initiation. 9.54% of these cases resulted in disability. Data mining results showed 5 ICIs generated positive uveitis signals when used alone. Ipilimumab yielded the most noticeable uveitis signal with the highest reporting odds ratio (ROR = 6.73, 95% two-sided CI = 5.26, 8.60), proportional reporting ratio (PRR = 6.69, χ²=308.52), information component (IC = 2.74, IC025 = 2.14) and empirical Bayes geometric mean (EBGM = 6.66, EBGM05 = 5.42), followed by pembrolizumab, cemiplimab, nivolumab and atezolizumab. When nivolumab, pembrolizumab or atezolizumab was administrated together with ipilimumab, obviously stronger uveitis signal was detected than that for either of them.

CONCLUSIONS

This study provided an overview of the clinical features of ICI-related uveitis cases in the FAERS. Data mining results revealed that positive uveitis signals commonly existed within this drug class, but signal strength varied among ICIs. When ICIs were used in a combined way, uveitis signals became obviously stronger. Therefore, early ophthalmic monitoring is important when applying ICIs to patients, especially those with a tendency for uveitis, such as melanoma patients.

Extracellular vesicles as a new horizon in the diagnosis and treatment of inflammatory eye diseases: A narrative review of the literature

Extracellular vesicles include exosomes, microvesicles, and apoptotic bodies. Their cargos contain a diverse variety of lipids, proteins, and nucleic acids that are involved in both normal physiology and pathology of the ocular system. Thus, studying extracellular vesicles may lead to a more comprehensive understanding of the pathogenesis, diagnosis, and even potential treatments for various diseases. The roles of extracellular vesicles in inflammatory eye disorders have been widely investigated in recent years. The term "inflammatory eye diseases" refers to a variety of eye conditions such as inflammation-related diseases, degenerative conditions with remarkable inflammatory components, neuropathy, and tumors. This study presents an overview of extracellular vesicles' and exosomes' pathogenic, diagnostic, and therapeutic values in inflammatory eye diseases, as well as existing and potential challenges.

Intravitreal injection versus systematic treatment in patients with uveitis undergoing cataract surgery: a systematic review and meta-analysis

PURPOSE

Cataract surgery in patients with uveitis is challenging, and postoperative inflammation control is crucial for successful outcomes. No consensus exists regarding the optimal method of controlling postoperative inflammation. In this systematic review and meta-analysis, we compared the outcome of intravitreal injection (IVI), including steroid (triamcinolone acetonide) or steroid implant (dexamethasone), with systemic anti-inflammatory therapy (ST), such as systemic steroids with or without immunomodulatory therapy, in patients with uveitis undergoing cataract surgery.

METHODS

We searched PubMed, EMBASE, and Cochrane Library databases for randomized controlled trials (RCTs), comparative cohort studies, and case-control studies published through May 2021 that compared intraoperative IVI of triamcinolone acetonide or steroid implant with ST with or without immunomodulatory therapy. The following outcomes were evaluated: preoperative best-corrected visual acuity, intraocular pressure, laser flare photometry, central macular thickness and cystoid macular edema rate.

RESULTS

Five studies were selected. Our analysis indicated that compared with ST, IVI treatment may be associated with less anterior chamber inflammation and a lower cystoid macular edema rate, but the difference in best-corrected visual acuity, intraocular pressure, or central macular thickness was not significant.

CONCLUSIONS

IVI of steroid or steroid implants might be beneficial in controlling postoperative inflammation for uveitis cataract, especially in patients who cannot tolerate ST. To the best of our knowledge, this is the first meta-analysis to compare the efficacy of intraoperative IVI of steroids with standard-of-care treatment as a prophylaxis for uveitis cataract. However, large-scale RCTs are warranted to compare the IVI of steroid implants and steroids.

Decoding the Key Functional Combined Components Group and Uncovering the Molecular Mechanism of Longdan Xiegan Decoction in Treating Uveitis

Objective

Longdan Xiegan Decoction (LXD) is a famous herbal formula in China. It has been proved that LXD has been shown to have a significant inhibitory effect on suppresses the inflammatory cells associated with uveitis. However, the key functional combination of component groups and their possible mechanisms remain unclear.

Methods

The community detecting model of the network, the functional response space, and reverse prediction model were utilized to decode the key components group (KCG) and possible mechanism of LXD in treating uveitis. Finally, MTT assay, NO assay and ELISA assay were applied to verify the effectiveness of KCG and the accuracy of our strategy.

Results

In the components-targets-pathogenic genes-disease (CTP) network, a combination of Huffman coding and random walk algorithm was used and eight foundational acting communities (FACs) were discovered with important functional significance. Verification has shown that FACs can represent the corresponding C-T network for treating uveitis. A novel node importance calculation method was designed to construct the functional response space and pick out 349 effective proteins. A total of 54 components were screened and defined as KCG. The pathway enrichment results showed that KCG and their targets enriched signal pathways of IL-17, Toll-like receptor, and T cell receptor played an important role in the pathogenesis of uveitis. Furthermore, experimental verification results showed that important KCG quercetin and sitosterol markedly inhibited the production of nitric oxide and significantly regulated the level of TNF-α and IFN-γ in Lipopolysaccharide-induced RAW264.7 cells.

Discussion

In this research, we decoded the potential mechanism of the multi-components-genes-pathways of LXD’s pharmacological action mode against uveitis based on an integrated pharmacology approach. The results provided a new perspective for the future studies of the anti-uveitis mechanism of traditional Chinese medicine.

Analysis of differentially expressed genes in individuals with noninfectious uveitis based on data in the gene expression omnibus database

Noninfectious uveitis (NIU), an intraocular inflammation caused by immune-mediated reactions to eye antigens, is associated with systemic rheumatism and several autoimmune diseases. However, the mechanisms underlying the pathogenesis of uveitis are poorly understood. Therefore, we aimed to identify differentially expressed genes (DEGs) in individuals with NIU and to explore its etiologies using bioinformatics tools. GSE66936 and GSE18781 datasets from the gene expression omnibus (GEO) database were merged and analyzed. Functional enrichment analysis was performed, and protein-protein interaction (PPI) networks were constructed. A total of 89 DEGs were identified. Gene ontology (GO) enrichment analysis identified 21 enriched gene sets. Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis identified four core enriched pathways: antigen processing and expression signaling, natural killer (NK) cell-mediated cytotoxicity signaling, glutathione metabolic signal transduction, and arachidonic acid metabolism pathways. PPI network analysis revealed an active component-target network with 40 nodes and 132 edges, as well as several hub genes, including CD27, LTF, NCR3, SLC4A1, CD69, KLRB1, KIR2DL3, KIR3DL1, and GZMK. The eight potential hub genes may be associated with the risk of developing NIU. NK cell-mediated cytotoxicity signaling might be the key molecular mechanism in the occurrence and development of NIU. Our study provided new insights on NIU, its genetics, molecular pathogenesis and new therapeutic targets.

Imaging of Painful Ophthalmologic Disorders

Cross-sectional imaging with computed tomography (CT) and MRI are diagnostic examinations useful in the diagnosis of painful ophthalmologic disorders and their potential complications. CT is a first-line imaging study for suspected orbital infections, particularly useful in differentiating preseptal cellulitis and orbital cellulitis and detecting complications such as orbital abscess. When compared with CT, MRI is better for orbital soft tissue evaluation, particularly useful for optic neuritis, ocular diseases such as endophthalmitis, and invasive fungal rhinosinusitis with orbital involvement. CT angiography is the preferred noninvasive imaging modality for the detection and classification of carotid cavernous fistula.

Vitreous proteomics, a gateway to improved understanding and stratification of diverse uveitis aetiologies

PURPOSE

The vitreous proteome might provide an attractive gateway to discriminate between various uveitis aetiologies and gain novel insights into the underlying pathophysiological processes. Here, we investigated 180 vitreous proteins to discover novel biomarkers and broaden disease insights by comparing (1). primary vitreoretinal lymphoma ((P)VRL) versus other aetiologies, (2). sarcoid uveitis versus tuberculosis (TB)-associated uveitis and (3). granulomatous (sarcoid and TB) uveitis versus other aetiologies.

METHODS

Vitreous protein levels were determined by proximity extension assay in 47 patients with intraocular inflammation and a prestudy diagnosis (cohort 1; training) and 22 patients with a blinded diagnosis (cohort 2; validation). Differentially expressed proteins identified by t-tests on cohort 1 were used to calculate Youden's indices. Pathway and network analysis was performed by ingenuity pathway analysis. A random forest classifier was trained to predict the diagnosis of blinded patients.

RESULTS

For (P)VRL stratification, the previously reported combined diagnostic value of IL-10 and IL-6 was confirmed. Additionally, CD70 was identified as potential novel marker for (P)VRL. However, the classifier trained on the entire cohort (cohort 1 and 2) relied primarily on the interleukin score for intraocular lymphoma diagnosis (ISOLD) or IL-10/IL-6 ratio and only showed a supportive role for CD70. Furthermore, sarcoid uveitis displayed increased levels of vitreous CCL17 as compared to TB-associated uveitis.

CONCLUSION

We underline the previously reported value of the ISOLD and the IL-10/IL-6 ratio for (P)VRL identification and present CD70 as a potentially valuable target for (P)VRL stratification. Finally, we also show that increased CCL17 levels might help to distinguish sarcoid uveitis from TB-associated uveitis.

Anti-Inflammatory Effects of GM1 Ganglioside on Endotoxin-Induced Uveitis in Rats

Exogenous ganglioside GM1 has been reported to exert an immunomodulatory effect. We investigated the anti-inflammatory effect of GM1 ganglioside on endotoxin-induced uveitis (EIU) in rats and RAW 264.7 macrophages. Methods: EIU was induced in Lewis rats by administering a subcutaneous injection of lipopolysaccharide (LPS). GM1 was injected intraperitoneally for three consecutive days prior to the LPS injection. Twenty-four hours after the LPS injection, the integrity of the blood-aqueous barrier was evaluated by determining the protein concentration and number of infiltrating cells in the aqueous humor (AqH). Immunohistochemical and Western blot analyses of the iris-ciliary body (ICB) were performed to evaluate the effect of GM1 on the LPS-induced expression of cyclooxygenase-2 (COX-2) and intercellular adhesion molecule-1 (ICAM-1). The effect of GM1 on proinflammatory mediators and signaling cascades was examined in LPS-stimulated RAW 264.7 cells using Western blotting and immunofluorescence staining to further clarify the underlying anti-inflammatory mechanism. Results: GM1 significantly reduced the protein concentration and number of infiltrating cells in the AqH of rats with EIU. GM1 also decreased the LPS-induced expression of the ICAM-1 and COX-2 proteins in the ICB. In RAW 264.7 cells, GM1 inhibited the proinflammatory mediators induced by LPS, including inducible nitric oxide synthase (iNOS), COX-2, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6), and this inhibitory effect was potentially mediated by suppressing transforming growth factor-β-activated kinase 1 (TAK1) and reactive oxygen species (ROS)-mediated activation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). Conclusions: Based on this study, GM1 may be a potential anti-inflammatory agent for ocular inflammatory diseases.

Therapeutic Potential of Microvesicles in Cell Therapy and Regenerative Medicine of Ocular Diseases With an Especial Focus on Mesenchymal Stem Cells-Derived Microvesicles

These days, mesenchymal stem cells (MSCs), because of immunomodulatory and pro-angiogenic abilities, are known as inevitable factors in regenerative medicine and cell therapy in different diseases such as ocular disorder. Moreover, researchers have indicated that exosome possess an essential potential in the therapeutic application of ocular disease. MSC-derived exosome (MSC-DE) have been identified as efficient as MSCs for treatment of eye injuries due to their small size and rapid diffusion all over the eye. MSC-DEs easily transfer their ingredients such as miRNAs, proteins, and cytokines to the inner layer in the eye and increase the reconstruction of the injured area. Furthermore, MSC-DEs deliver their immunomodulatory cargos in inflamed sites and inhibit immune cell migration, resulting in improvement of autoimmune uveitis. Interestingly, therapeutic effects were shown only in animal models that received MSC-DE. In this review, we summarized the therapeutic potential of MSCs and MSC-DE in cell therapy and regenerative medicine of ocular diseases.

Effect of small extracellular vesicles derived from IL-10-overexpressing mesenchymal stem cells on experimental autoimmune uveitis

BACKGROUND

Autoimmune uveitis is a sight-threatening intraocular inflammation mainly caused by immune dysregulation. The development of safe and effective therapeutic approaches is urgently needed. Small extracellular vesicles (sEVs) derived from mesenchymal stem cells (MSCs) have been demonstrated to inhibit autoimmune responses; however, the immunosuppressive effect of MSC-sEVs is too weak for clinical transfer. In the current study, we investigated the therapeutic effect of IL-10-overexpressing MSC-sEVs (sEV-IL10) on experimental autoimmune uveitis (EAU) and studied the underlying mechanism.

METHODS

Mice were randomly grouped and received a single tail vein injection of different sEVs (50 μg) or PBS on day 11 post-immunization. The clinical and histological scores were graded, and the percentage of T helper cell was measured. To investigate the effect of sEVs on the proliferation of T-cells and the differentiation of Th1, Th17 and Treg cells, T-cells were cocultured with sEVs under the corresponding culture conditions. After labeled with PKH-26, sEVs were traced both in vivo and in vitro.

RESULTS

Compared with normal or vector sEV-treated groups, mice in the sEV-IL10-treated group had lower clinical and histological scores with lower percentages of Th1 and Th17 cells in the eyes and higher percentages of Treg cells in the spleen and draining lymph nodes (LN). Furthermore, sEV-IL10 enhanced the suppressive effect of MSC-sEVs on the proliferation of T-cells and differentiation of Th1 and Th17 cells, whereas upregulated the differentiation of Treg cells. Both in vivo and in vitro experiments demonstrated that MSC-sEVs were rapidly enriched in target tissues and internalized by T-cells.

CONCLUSION

These results suggested that sEV-IL10 effectively ameliorates EAU by regulating the proliferation and differentiation of T-cells, indicating sEVs as a potential novel therapy for autoimmune uveitis or other autoimmune diseases.

Proteome Analysis of Urinary Biomarkers in a Bovine IRBP-Induced Uveitis Rat Model via Data-Independent Acquisition and Parallel Reaction Monitoring Proteomics

Uveitis, a group of intraocular inflammatory diseases, is one of the major causes of severe visual impairment among the working-age population. This study aimed to screen potential urinary biomarkers for uveitis based on proteome analysis. An experimental autoimmune uveitis (EAU) rat model induced by bovine interphotoreceptor retinoid-binding protein (IRBP) was used to mimic uveitis. In discovery phase, a total of 704 urinary proteins were identified via data-independent acquisition (DIA) proteomic technique, of which 76 were significantly changed (34, 36, and 37 on days 5, 8, and 12, respectively, after bovine IRBP immunization). Gene Ontology annotation of the differential proteins indicates that acute-phase response, innate immune response, neutrophil aggregation, and chronic inflammatory response were significantly enriched. Protein-protein interaction network indicates that these differential urinary proteins were biologically connected in EAU, as a group. In validation phase, 17 proteins having human orthologs were verified as the potential markers associated with uveitis by parallel reaction monitoring (PRM) targeted quantitative analysis. Twelve differential proteins changed even when there were no clinical manifestations or histopathological ocular damage. These 12 proteins are potential biomarkers for early diagnosis of uveitis to prevent the development of visual impairment. Five differential proteins changed at three time-points and showed progressive changes as the uveitis progressed, and another five differential proteins changed only on day 12 when EAU severity peaked. These 10 proteins may serve as potential biomarkers for prognostic evaluation of uveitis. Our findings revealed that the urinary proteome could sensitively reflect dynamic pathophysiological changes in EAU, and represent the first step towards the application of urinary protein biomarkers for uveitis.

Enhanced Ectasia Screening in Patients with Uveitis and Isolated Systemic Inflammatory Disease

PURPOSE

To investigate corneal topographic alterations in patients with uveitis and isolated systemic inflammatory disease (SID).

METHODS

This retrospective cross-sectional study included 44 patients with uveitis with anterior chamber inflammation (uveitis group), 39 subjects with isolated SID, and 91 healthy controls (control group). Topographic images were classified as "normal," "keratoconus (KC) suspect" and "KC" based on maps of axial curvature, corneal thickness, front and back elevation in combination with Belin/Ambrósio Enhanced Ectasia Display (BAD).

RESULTS

The uveitis and SID groups had higher incidence of KC (6.8% and 10.2%, respectively) and KC suspect (45.5% and 33.3%, respectively), whereas 2.2% of the control subjects had KC and 26.4% represented KC suspect (p < .05).

CONCLUSIONS

Patients with uveitis with or without SID, and isolated SID without intraocular inflammation seem to be more likely to have KC and KC suspect, which might be due to systemic and/or local inflammatory background triggering pathophysiological mechanisms underlying KC.

Anti-inflammatory Effects of GTE in Eye Diseases

Ocular inflammation is a common complication of various eye diseases with wide consequences from irritations to potentially sight-threatening complications. Green tea is a popular beverage throughout the world. One of the proven health benefits of consuming green tea extract (GTE) is anti-inflammation. Catechins are the biologically active constituents of GTE. In in vitro and in vivo studies, GTE and catechins present inhibition of inflammatory responses in the development of ocular inflammation including infectious, non-infectious or autoimmune, and oxidative-induced complications. Research on the ocular inflammation in animal models has made significant progress in the past decades and several key disease mechanisms have been identified. Here we review the experimental investigations on the effects of GTE and catechins on various ocular inflammation related diseases including glaucoma, age-related macular degeneration, uveitis and ocular surface inflammation. We also review the pharmacokinetics of GTE constituents and safety of green tea consumption. We discuss the insights and perspectives of these experimental results, which would be useful for future development of novel therapeutics in human.

Uveitis and autoimmune hepatitis, a real entity? A case report with review of the literature

A 63-year-old man presented with a 10-day history of severe pain, redness of the right eye, and reduced vision in both eyes. In addition, he had been diagnosed incidentally with liver cirrhosis and splenomegaly 1 week before he was admitted to our center. The patient was found to have severe intraocular inflammation that initially involved the right eye and then progressed to bilateral panuveitis. The presenting visual acuity was 20/60 for the left eye and lumbar puncture (LP) for the right eye. Vitreous tap revealed a nonturbid, yellow fluid that was negative for organism culture, polymerase chain reaction (PCR), and tumor markers. Oral prednisolone significantly improved the clinical status of both ocular and hepatic inflammation. During the admission period, the patient developed several medical comorbid complications that temporarily altered the management of our case. After a full evaluation of uveitis causes, the patient was diagnosed with biopsy-proven autoimmune hepatitis. In addition to a high-dose oral steroid, azathioprine was given for 3 months before the patient developed decompensated liver failure, which was successfully managed with a liver transplant. The patient was stable for 1 year following the transplant but eventually developed blindness of the right eye and visual acuity of 20/30 in the left eye.

Effects of Mesenchymal Stem Cell-Derived Exosomes on Autoimmune Diseases

Recent years, the immunosuppressive properties of mesenchymal stem cells (MSCs) have been demonstrated in preclinical studies and trials of inflammatory and autoimmune diseases. Emerging evidence indicates that the immunomodulatory effect of MSCs is primarily attributed to the paracrine pathway. As one of the key paracrine effectors, mesenchymal stem cell-derived exosomes (MSC-EXOs) are small vesicles 30-200 nm in diameter that play an important role in cell-to-cell communication by carrying bioactive substances from parental cells. Recent studies support the finding that MSC-EXOs have an obvious inhibitory effect toward different effector cells involved in the innate and adaptive immune response. Moreover, substantial progress has been made in the treatment of autoimmune diseases, including multiple sclerosis (MS), systemic lupus erythematosus (SLE), type-1 diabetes (T1DM), uveitis, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD). MSC-EXOs are capable of reproducing MSC function and overcoming the limitations of traditional cell therapy. Therefore, using MSC-EXOs instead of MSCs to treat autoimmune diseases appears to be a promising cell-free treatment strategy. In this review, we review the current understanding of MSC-EXOs and discuss the regulatory role of MSC-EXOs on immune cells and its potential application in autoimmune diseases.

Reliability of Aqueous Flare Measurements During Uveitis by a Spot Fluorometer

Purpose: To evaluate the reliability of intensity of light scatter (ILS) for diagnosing mild-to-moderate uveitis, which is difficult to score by the subjective standardized uveitis nomenclature (SUN) grading. Methods: ILS (in millivolts) was measured in healthy subjects and uveitis patients by a custom-made Spot fluorometer. The reliability was assessed by noise analysis of the instrument using turbid samples and intra- and interobserver variabilities. Results: ILS increased with the severity of inflammation: healthy (0.1498 ± 0.0564) and SUN0 (0.1590 ± 0.0564) < SUN1+ (0.2050 ± 0.0887) < SUN2+ (0.4283 ± 0.1895). The increase in ILS was more significant between healthy and SUN1+ (P < 0.0001) compared to the difference between SUN0 and SUN1+ (P = 0.0006). The instrument noise was small (σ = 0.002). Intraobserver measurements revealed no variability (P > 0.98) between measurements and predicted repeatability coefficients of 0.0754, 0.0522, and 0.0532 in healthy, SUN0, and SUN1+, respectively. Interobserver measurements also showed no variability (P > 0.88) and predicted intraclass correlation coefficient > 0.63 in healthy and uveitis subjects. Conclusions: The fluorometer enables precise measurement of ILS with negligible instrument noise, and the measurements are unaffected by intra- and interobserver variabilities. However, the difference in mean ILS between SUN0 and SUN1+ is greater than the instrument noise and comparable to intra- and interobserver variabilities. Thus, ILS measurements are likely impacted by blinking, eye movements, and focusing jitter. The impact of these factors must be reduced before using the fluorometer to distinguish mild-to-moderate uveitis.

The Efficacy and Safety of Infliximab in Refractory Noninfectious Uveitis: A Meta-Analysis of Observational Studies

Background: Although infliximab has been recommended for the second-line treatment of seronegative spondyloarthropathy- or juvenile idiopathic arthritis-related uveitis, the issue of its systemic efficacy and safety in a broader diversity of refractory noninfectious uveitis is debatable. To assess the short-term and relatively long-term efficacy of infliximab in refractory noninfectious uveitis, we performed a systematic review and meta-analysis of observational studies.

Methods: PubMed, Cochrane Library, EMBASE, and Wanfang Med Online were systematically searched from January 2005 to March 2020. Two investigators independently assessed eligibility. Data were independently collected by two investigators. The pooled proportions were estimated with patients for intraocular inflammation control and improvement of visual acuity. Pooled proportions with 95% credible intervals were computed. Study homogeneity was investigated using I² statistics to quantify the percentage of variation across studies. To pool the results, the Mantel–Haenszel fixed-effects or random-effects models were used.

Results: Of 2316 studies identified, 16 unique studies with 509 unique participants were included in the meta-analysis. The pooled proportions of intraocular inflammation control reached 92% (95% CI: 87%–98%; I²: 1%; p=0.42) and 95% (95% CI: 93%–97%; I²: 0%; p=0.91) in groups of ≤6- and ≥12-month follow-up durations. During the relatively long follow-up period, the pooled proportions of maintaining visual acuity stable or increasing at least one line reached 99% (95% CI: 96%–100%; I²: 0%; p=0.54) in the involved eyes. The corticosteroid-sparing effect of infliximab was also well demonstrated, with the proportion of corticosteroid-sparing success reaching 85.5% (112/131). Besides, about serious adverse events, 2.6% (13/500) of patients experienced hypersensitivity reactions, 2.4% (12/500) of patients experienced serious infections, 1.8% (9/500) of patients experienced autoimmune diseases, and 0.6% (3/500) of patients experienced neoplasia.

Conclusions: This meta-analysis provided evidence that infliximab might be a promising choice in controlling inflammatory activity, gaining visual acuity, and sparing corticosteroid use with relatively few side effects when applied in treating refractory noninfectious uveitis.

Systematic Review Registration: [website], identifier [registration number]

Ocular Immune-Related Adverse Events Associated With Immune Checkpoint Inhibitors in Lung Cancer

Immune checkpoint inhibitors (ICIs) are novel immunotherapy-based drugs that have become increasingly popular in the treatment of lung cancer. Researchers have recognized ocular immune-related adverse events (irAEs) secondary to ICIs because of their vision-threatening characteristics. However, they are incompletely characterized and no studies have reported the ICI-related ocular irAEs in lung cancer. Therefore, we aimed to comprehensively illustrate the clinical characteristics, contributory factors, diagnosis, and management of ICI-related ocular irAEs in lung cancer, based on previously reported 79 patients. Ophthalmoplegia (40.51%), uveitis (20.25%), and dry eye (17.72%) were the most common ICI-related ocular irAEs in lung cancer. Ptosis was the most common (36.71%) and the highest mortality (23.33%) of ophthalmoplegia. Patients in Asia and patients who underwent combination therapy with programmed cell death-1 and cytotoxic T-lymphocyte-associated antigen 4 inhibitors demonstrated significantly higher frequency of ophthalmoplegia than other ocular irAEs. Most ICI-related ophthalmoplegia and uveitis in lung cancer were observed in the first 10 weeks following the initiation of ICIs. Furthermore, the onset time of dry eye and other ocular irAEs was much longer. In addition, 92.31% of the patients with ocular irAEs other than ophthalmoplegia could be remised. In conclusion, ocular irAEs secondary to ICIs in lung cancer are non-negligible, particularly ophthalmoplegia. Ethnicity and the type of ICIs play important roles in the distribution of ocular irAEs. ICI-related ophthalmoplegia in lung cancer presented with early onset and worse prognosis features, thus necessitating further attention.