Pathogenesis of Non-Infectious Uveitis Elucidated by Recent Genetic Findings

Peptide-based hydrogel co-assembled with antibody-drug for enhanced retinal cell uptake and attenuated experimental autoimmune uveitis

Effective treatment of chronic posterior ocular diseases such as uveitis, diabetic retinopathy, and age-related macular degeneration requires improvements in targeted drug delivery strategies. This study introduces a novel injectable drug delivery system co-assembled with a peptide-based hydrogel and secukinumab (SEK), an IL-17A neutralising monoclonal antibody, targeting retinal pigmented epithelium (RPE) cells. Compared to a SEK solution, the SEK loaded hydrogel significantly enhanced the protein uptake (3.7 times higher) by RPE cells in an inflammatory state after 24 hours of treatment and increased the drug concentration in retinal tissues during 20 days of treatment. A single intravitreal injection of the SEK loaded hydrogel effectively suppressed inflammation in a uveitis model. It also reduced the immunoreactivity of microglia and T helper 17 cells, preserved the integrity of the blood-retina barrier, mitigated retinal cell apoptosis, and facilitated the recovery of the retinal function. This delivery system comprising an antibody-drug co-assembled with a peptide-based hydrogel shows promising potential for targeting the retina and treating complex chronic posterior ocular diseases.

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.

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.

Arctiin suppress Th17 cells response and ameliorates experimental autoimmune uveitis through JAK/STAT signaling

Conventional treatments for autoimmune uveitis, such as corticosteroids and systemic immunosuppressants, often result in adverse side effects, prompting the need for therapies targeting specific molecular pathways. This study investigates the effects of Arctiin, known for its diverse biological properties, on experimental autoimmune uveitis (EAU) through its action on Th17 cells and the JAK/STAT signaling pathway. Our findings reveal that Arctiin significantly alleviates EAU by reducing clinical scores, inflammatory cell infiltration, and levels of inflammatory cytokines like IL-17 and TNF-α in the eye. Arctiin achieves this by activating adiponectin receptor 1 (AdipoR1), which modulates the JAK/STAT pathway, thereby inhibiting Th17 cell differentiation and cytokine secretion. Additionally, Arctiin effectively suppresses IRBP-specific Th17 cell activation in cervical lymph nodes, further mitigating retinal inflammation and tissue damage. These results underscore Arctiin's potential as a therapeutic agent for uveitis and other autoimmune inflammatory disorders through the modulation of the AdipoR1/JAK/STAT pathway in Th17 cells.

RNA methylation homeostasis in ocular diseases: All eyes on Me

RNA methylation is a pivotal epigenetic modification that adjusts various aspects of RNA biology, including nuclear transport, stability, and the efficiency of translation for specific RNA candidates. The methylation of RNA involves the addition of methyl groups to specific bases and can occur at different sites, resulting in distinct forms, such as N6-methyladenosine (m6A), N1-methyladenosine (m1A), 5-methylcytosine (m5C), and 7-methylguanosine (m7G). Maintaining an optimal equilibrium of RNA methylation is crucial for fundamental cellular activities such as cell survival, proliferation, and migration. The balance of RNA methylation is linked to various pathophysiological conditions, including senescence, cancer development, stress responses, and blood vessel formation, all of which are pivotal for comprehending a spectrum of eye diseases. Recent findings have highlighted the significant role of diverse RNA methylation patterns in ophthalmological conditions such as age-related macular degeneration, diabetic retinopathy, cataracts, glaucoma, uveitis, retinoblastoma, uveal melanoma, thyroid eye disease, and myopia, which are critical for vision health. This thorough review endeavors to dissect the influence of RNA methylation on common and vision-impairing ocular disorders. It explores the nuanced roles that RNA methylation plays in key pathophysiological mechanisms, such as oxidative stress and angiogenesis, which are integral to the onset and progression of these diseases. By synthesizing the latest research, this review offers valuable insights into how RNA methylation could be harnessed for therapeutic interventions in the field of ophthalmology.

Long-acting release of fluocinolone acetonide microspheres using electrospray technology for noninfectious uveitis therapy

Intravitreous long-acting drug delivery system offers an excellent alternative to multiple injections for the treatment of noninfectious uveitis (NIU). However, the adverse effects of non-biodegradable intravitreal implants of fluocinolone acetonide (FA), such as postoperative hypotony and secondary injury during removal of the implant matrix, are frequent occurrence to affect patient's compliance. Herein, biodegradable poly (lactic-co-glycolic acid) (PLGA)-based microspheres (MS) containing fluocinolone acetonide (FA@MS) were prepared using an optimized electrospray technology with a voltage of 10.07 kV and the receiving distance of 9.87 cm. The obtained FA@MS with the average particle size of 2.25 μm possessed the high encapsulation efficiency (94.85%) and drug content (9.48%). In vitro release demonstrated that FA@MS exhibited sustained release for 30 days, and the release characteristic of FA@MS conformed to the Weibull model. In vivo study in a rabbit NIU model indicated that FA@MS continuously released the drug for at least 28 days in vitreum and progressively decreased inflammation of NIU. Furthermore, the intraocular pressure of rabbits treated with blank MS and FA@MS remained the normal level for 28 days, which demonstrated the favorable biosafety of FA@MS. In conclusion, long-acting release of FA@MS provides a promising formulation for NIU treatment. HIGHLIGHTSA biodegradable FA@MS was prepared using the modified electrospray technology for intravitreal administration.FA@MS exhibited the sustained release characteristics for 30 days in the medium of PBS (pH 7.4) with 0.2% Tween 80.The pharmacodynamics indicated that FA@MS could be continuously released for at least 28 days in vitreum to treat NIU.

Long-term outcomes of noninfectious uveitis treated with systemic immunomodulatory therapy: a retrospective case series

OBJECTIVE

To study the clinical characteristics and long-term outcomes of patients with noninfectious uveitis (NIU) who are treated with systemic immunomodulatory therapy (IMT).

DESIGN

Retrospective case series.

PARTICIPANTS

All consecutive cases of adults with NIU under the care of 5 uveitis subspecialty tertiary care clinics between 2010 to 2021 were included.

METHODS

Patient outcomes were assessed at initial presentation and at the latest available follow-up.

RESULTS

A total of 418 NIU patients receiving IMT therapy with a median age of 46.0 years and 59.3% female were identified. Each patient required an average of 1.4 agents until achieving an optimal response. Following initial treatment with prednisone, patients were most commonly initiated on methotrexate. The top 3 treatments with the highest proportion of optimal treatment response when taken alone or in combination with other agents were infliximab (79.3%), cyclosporine (75%), and adalimumab (70%). The strongest predictors for requiring a greater number of IMTs trialed were younger age, panuveitis, and a chronic or recurrent disease course. Multivariable linear regression analysis suggested that baseline visual acuity at diagnosis was the only significant predictor of final visual acuity (p < 0.001).

CONCLUSIONS

NIU patients on IMT are often trialed on multiple therapeutic agents before achieving an optimal treatment response. Visual acuity at diagnosis is a predictor of final visual outcomes, whereas chronic or recurrent disease course, younger age, and panuveitis are predictors of requiring multiagent treatment regimens.

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.

Changes of peripheral blood Th cytokines in acute anterior uveitis and their relationships with recurrence

Acute anterior uveitis (AAU) can cause great pain to patients. Th cytokines in peripheral blood are significantly changed in these patients, including serum interleukin-23 (IL-23), interleukin-17 (IL-17), interleukin-4 (IL-4), interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1) increase. However, the relationship between Th cytokines and recurrence of AAU is still unclear. Ninety-two cases of AAU were enrolled from January 2020 to April 2022 in our hospital (observation group). Levels of peripheral blood Th cytokines were detected, which were compared between acute and remission stages. After 6 months of follow-up, the relationships between Th cytokines in peripheral blood and recurrence in the observation group were analyzed. The prediction of Th cytokines on recurrence was analyzed. (1) The recurrence rate was 25.00%, and there were no statistical differences in the serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels between patients with bilateral disease and unilateral disease (P < 0.05). (2) The serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels of recurrence patients were higher than those of non-recurrence (t = 2.971, 5.357, 2.197, 2.766, 4.395, 2.983, P < 0.05). (3) The serum IL-23, IL-17, TNF-α levels were risk factors for recurrence (OR = 1.035, 1.210, 1.155, P < 0.05). (4) There were positive relationships between serum IL-23, IL-17, IL-4, IFN-γ, TNF-α and TGF-β 1 levels and recurrence (r = 0.317, 0.526, 0.248, 0.304, 0.480, 0.325, P < 0.05).            .

Association between iridocyclitis and immune-related disease: A 2-sample Mendelian randomization study

The genetic basis of iridocyclitis, an inflammatory eye disease, remains poorly understood, particularly in relation to autoimmune diseases. This study aimed to explore the causal associations between 6 immune-related diseases and iridocyclitis using Mendelian randomization (MR). A total of 230 single nucleotide polymorphisms (SNPs) significantly associated with systemic lupus erythematosus, ankylosing spondylitis (AS), rheumatoid arthritis (RA), Graves disease (GD), Crohn disease (CD), and allergic contact dermatitis were identified based on stringent MR assumptions. These SNPs served as instrumental variables to estimate the causal effect of each autoimmune disease on iridocyclitis risk. The analysis utilized the inverse variance weighted method, complemented by sensitivity analyses including MR-Egger regression and leave-one-out testing to assess pleiotropy and robustness. The MR analysis revealed significant associations between genetically predicted AS (odds ratio [OR]: 1.544, 95% confidence interval [CI]: 1.494-1.595, P = 1.99 × 10-226), RA (OR: 1.207, 95% CI: 1.052-1.385, P = .003), and CD (OR: 1.654, 95% CI: 1.263-2.166, P = 2.54 × 10⁻⁶) with an increased risk of iridocyclitis. Conversely, higher genetically predicted GD was associated with a decreased risk of iridocyclitis (OR: 0.763, 95% CI: 0.674-0.865, P = .0002). Although systemic lupus erythematosus and allergic contact dermatitis appeared to have a protective effect, these results were not statistically significant, and no causal relationship could be established. Heterogeneity was observed among the SNPs, but no significant horizontal pleiotropy was detected. This study identifies potential genetic links between AS, RA, CD, GD, and the risk of iridocyclitis, providing new insights into the genetic underpinnings of this eye disease. The results support the need for further investigation into the genetic and molecular mechanisms underlying these associations.

"Infectious uveitis: a comprehensive systematic review of emerging trends and molecular pathogenesis using network analysis"

BACKGROUND

Infectious uveitis is a significant cause of visual impairment worldwide, caused by diverse pathogens such as viruses, bacteria, fungi, and parasites. Understanding its prevalence, etiology, pathogenesis, molecular mechanism, and clinical manifestations is essential for effective diagnosis and management.

METHODS

A systematic literature search was conducted using PubMed, Google Scholar, Web of Science, Scopus, and Embase, focusing on studies published in the last fifteen years from 2009 to 2023. Keywords included "uveitis," "infectious uveitis," "viral uveitis," and others. Rigorous inclusion and exclusion criteria were applied, and data were synthesized thematically. Gene symbols related to infectious uveitis were analyzed using protein-protein interaction (PPI) networks and pathway analyses to uncover molecular mechanisms associated with infectious uveitis.

RESULTS

The search from different databases yielded 97 eligible studies. The review identified a significant rise in publications on infectious uveitis, particularly viral uveitis, over the past fifteen years. Infectious uveitis prevalence varies geographically, with high rates in developing regions due to systemic infections and limited diagnostic resources. Etiologies include viruses (39%), bacteria (17%), and other pathogens, substantially impacting adults aged 20-50 years. Pathogenesis involves complex interactions between infectious agents and the ocular immune response, with key roles for cytokines and chemokines. The PPI network highlighted IFNG, IL6, TNF, and CD4 as central nodes. Enriched pathways included cytokine-cytokine receptor interaction and JAK-STAT signaling. Clinical manifestations range from anterior to posterior uveitis, with systemic symptoms often accompanying ocular signs. Diagnostic strategies encompass clinical evaluation, laboratory tests, and imaging, while management involves targeted antimicrobial therapy and anti-inflammatory agents.

CONCLUSION

This review underscores the complexity of infectious uveitis, driven by diverse pathogens and influenced by various geographical and systemic factors. Molecular insights from PPI networks and pathway analyses provide a deeper understanding of its pathogenesis. Effective management requires comprehensive diagnostic approaches and targeted therapeutic strategies.

A proliferation-inducing ligand (APRIL) level among risk factors of ocular involvement in patients with Behçet's disease

Introduction

Ocular involvement is quite common in Behçet's disease (BD) and may cause crucial functional complications. Even though the mechanisms of BD remain unclear, advances in genetic and immunological fields have improved our understanding of the immunopathogenesis of BD ocular involvement. Little is known about the expression of a proliferation-inducing ligand (APRIL) in terms of ocular involvement in BD. The objective of this study was to determine whether serum APRIL concentrations are associated with ocular involvement in patients with BD.

Material and methods

The study included 60 patients diagnosed with BD matched by age and sex to 30 healthy individuals. Every patient underwent a clinical evaluation, and the Behçet's Disease Current Activity Form (BDCAF) was utilized to quantify disease activity. All patients underwent a comprehensive ophthalmological assessment. Serum APRIL was assessed for patients as well as controls.

Results

One or more ocular manifestations were found in 42 BD patients (70%), while 18 patients (30%) had no ocular involvement. The mean level of serum APRIL levels was markedly elevated in BD patients, particularly those with ocular involvement, compared to both BD patients without ocular involvement and healthy individuals. A statistically significant association was determined between high APRIL concentration and development of uveitis, cataract, and hypopyon. Cutaneous lesions and arthritis were strong independent predictors for ocular involvement in BD patients.

Conclusions

Overexpression of APRIL in patients with BD, particularly in terms of uveitis, cataract, and hypopyon, lends credence to the idea that B cell activating factors have an important function in BD. These findings may indicate that serum APRIL concentrations can differentiate a clinical subgroup of BD patients with ocular disease. As a result, finding a new therapeutic strategy targeting the APRIL pathway might be beneficial in BD patients suffering from ocular involvement.

Regulatory role of the lncRNAs MIAT and PVT1 in Behçet's disease through targeting miR-93-5p and miR-124-3p

BACKGROUND

Noncoding RNAs play pivotal roles in the process of autoimmune diseases. However, the definite contributions of these molecules to Behçet's disease (BD) are still unknown. This study aimed to explore the clinical value of a novel competing endogenous (ce) RNA network in the pathogenesis of BD and to assess its use in primary diagnosis.

METHODS

Bioinformatic analysis was applied to construct a BD-related ceRNA network: lncRNA (MIAT and PVT1)-miRNA (miR-93-5p and miR-124-3p)-mRNA (SOD-2 and MICA). Blood was obtained from 70 BD patients and 30 healthy subjects, and the serum expression of the tested RNAs was estimated via quantitative real-time PCR (qPCR). Serum tumor necrosis factor-alpha (TNF-α) levels were also determined. The associations between these RNAs were further analyzed, and receiver operating characteristic (ROC) curve and logistic regression analyses were employed to validate their diagnostic and prognostic values.

RESULTS

The expression levels of the lncRNAs PVT1 and miR-93-5p were significantly increased, whereas those of the lncRNAs MIAT and miR-124-3p, as well as those of the SOD-2 and MICA mRNAs, were significantly decreased in BD patients compared with controls. BD patients had significantly higher serum TNF-α levels than controls did. ROC curve analysis indicated that the selected RNAs could be candidate diagnostic biomarkers for BD. Moreover, the highest diagnostic efficiency was achieved with the combination of MIAT and miR-93-5p or PVT1 and miR-124-3p with either SOD-2 or MICA. Logistic regression analysis revealed that all RNA expression levels could be predictors for BD.

CONCLUSION

Mechanistically, our research revealed a novel ceRNA network that is significantly disrupted in BD. The findings reported herein, highlight the noncoding RNA-molecular pathways underlying BD and identify potential targets for therapeutic intervention. These insights will likely be applicable for developing new strategies for the early diagnosis, management and risk assessment of BD as well as the design of novel preventive measures. Trial registration The protocol for the clinical studies was approved by Cairo University's Faculty of Pharmacy's Research Ethics Committee (approval number: BC 3590).

Overview of dendritic cells and related pathways in autoimmune uveitis

Dendritic cells (DCs) play a crucial role in bridging innate and adaptive immune responses. They are widely distributed in various tissues and organs, including the eyes. In the ocular context, permanent DCs are present at the peripheral edge of the retina and the peripapillary area in an immature state. However, during the inflammatory process, DCs become activated and contribute to the development of uveitis. This review focuses on introducing the characteristics and status of DC-induced uveitis, exploring factors that can influence the status of DCs, and discussing feasible methods for treating DCs in both experimental autoimmune uveitis animal models and humans. It emphasizes the importance of further research on molecular pathways and signaling pathways that regulate the function of DCs. For example, investigating molecules such as cytotoxic T-lymphocyte-associated protein 4, which inhibits the B7-CD28 co-stimulatory interaction, can help improve immune homeostasis. The aim is to identify new therapeutic targets and develop targeted strategies for DCs, such as DC vaccine therapy or the use of immune modulators. These approaches can be tailored to the immune characteristics and disease manifestations of individual patients, enabling personalized treatment strategies. This may include the personalized design and precise medication of DC therapy, with the ultimate goal of improving treatment efficacy while minimizing adverse reactions.

Management of JIA associated uveitis

Juvenile Idiopathic Arthritis (JIA) is the most common chronic rheumatic disease in childhood, and is associated with uveitis in up to 20-25% of cases. Typically, the uveitis is chronic, asymptomatic, non-granulomatous and anterior. For this reason, screening for uveitis is recommended to identify uveitis early and allow treatment to prevent sight-threatening complications. The management of JIA associated uveitis requires a multidisciplinary approach and a close collaboration between paediatric rheumatologist and ophthalmologist. Starting the appropriate treatment to control uveitis activity and prevent ocular complications is crucial. Current international recommendations advise a step-wise approach, starting with methotrexate and moving on to adalimumab if methotrexate alone is not sufficient to control the disease. If the uveitis remains active despite standard treatment other therapeutic options may be considered including anti-IL6 or other anti-TNF agents such as infliximab, although the evidence for these agents is limited.

Subconjunctival injection of rapamycin-loaded polymeric microparticles for effective suppression of noninfectious uveitis in rats

Noninfective uveitis is a major cause of vision impairment, and corticosteroid medication is a mainstay clinical strategy that causes severe side effects. Rapamycin (RAPA), a potent immunomodulator, is a promising treatment for noninfective uveitis. However, because high and frequent dosages are required, it is a great challenge to implement its clinical translation for noninfective uveitis therapy owing to its serious toxicity. In the present study, we engineered an injectable microparticulate drug delivery system based on biodegradable block polymers (i.e., polycaprolactone-poly (ethylene glycol)-polycaprolactone, PCEC) for efficient ocular delivery of RAPA via a subconjunctival injection route and investigated its therapeutic efficacy in an experimental autoimmune uveitis (EAU) rat model. RAPA-PCEC microparticles were fabricated using the emulsion-evaporation method and thoroughly characterized using scanning electron microscopy, fourier transform infrared spectroscopy, X-ray diffraction, and differential scanning calorimetry. The formed microparticles exhibited slow in vitro degradation over 28 days, and provided both in vitro and in vivo sustained release of RAPA over 4 weeks. Additionally, a single subconjunctival injection of PCEC microparticles resulted in high ocular tolerance. More importantly, subconjunctival injection of RAPA-PCEC microparticles significantly attenuated the clinical signs of EAU in a dose-dependent manner by reducing inflammatory cell infiltration (i.e., CD45+ cells and Th17 cells) and inhibiting microglial activation. Overall, this injectable microparticulate system may be promising vehicle for intraocular delivery of RAPA for the treatment of noninfective uveitis.

Repurposing of rituximab biosimilars to treat B cell mediated autoimmune diseases

Rituximab, the first monoclonal antibody approved for the treatment of lymphoma, eventually became one of the most popular and versatile drugs ever in terms of clinical application and revenue. Since its patent expiration, and consequently, the loss of exclusivity of the original biologic, its repurposing as an off-label drug has increased dramatically, propelled by the development and commercialization of its many biosimilars. Currently, rituximab is prescribed worldwide to treat a vast range of autoimmune diseases mediated by B cells. Here, we present a comprehensive overview of rituximab repurposing in 115 autoimmune diseases across 17 medical specialties, sourced from over 1530 publications. Our work highlights the extent of its off-label use and clinical benefits, underlining the success of rituximab repurposing for both common and orphan immune-related diseases. We discuss the scientific mechanism associated with its clinical efficacy and provide additional indications for which rituximab could be investigated. Our study presents rituximab as a flagship example of drug repurposing owing to its central role in targeting cluster of differentiate 20 positive (CD20) B cells in 115 autoimmune diseases.

Advance in pathogenesis of sarcoidosis: Triggers and progression

Sarcoidosis, a multisystemic immune disease, significantly impacts patients' quality of life. The complexity and diversity of its pathogenesis, coupled with limited comprehensive research, had hampered both diagnosis and treatment, resulting in an unsatisfactory prognosis for many patients. In recent years, the research had made surprising progress in the triggers of sarcoidosis (genetic inheritance, infection and environmental factors) and the abnormal regulations on immunity during the formation of granuloma. This review consolidated the latest findings on sarcoidosis research, providing a systematic exploration of advanced studies on triggers, immune-related regulatory mechanisms, and clinical applications. By synthesizing previous discoveries, we aimed to offer valuable insights for future research directions and the development of clinical diagnosis and treatment strategies.

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.

Succinic acid exacerbates experimental autoimmune uveitis by stimulating neutrophil extracellular traps formation via SUCNR1 receptor

AIMS

To investigate the effect of succinic acid on the development of experimental autoimmune uveitis (EAU) and the underlying mechanism.

METHODS

Succinic acid was administrated intraperitoneally to evaluate its effects on immune response and EAU in mice. Intraocular inflammation was evaluated by histopathological scoring. Frequencies of Th1/Th17 cells were measured by flow cytometry. Concentrations of IFN-γ/IL-17A, neutrophil elastase (NE) and myeloperoxidase (MPO) were determined by enzyme-linked immunosorbent test. Infiltration of neutrophils and generation of neutrophil extracellular traps (NETs) within the eye were assessed by immumofluorescence. NETs formation in extracellular matrix was visualised by laser scanning confocal microscopy. Succinate receptor (SUCNR1) antagonist was used to investigate its effect on the generation of NETs.

RESULTS

Intraperitoneal injection of succinic acid exacerbated EAU severity as evidenced by severe histological changes in association with elevated frequencies of splenic Th1/Th17 cells, and upregulated levels of IFN-γ/IL-17A and NETs in plasma. In vitro experiments showed that succinic acid could promote the generation of NETs by neutrophils as shown by increased expression of NE and MPO.NETs could increase the frequencies of Th1/Th17 cells in CD4+ T cells and their expression of IFN-γ/IL-17A. In the experiment of receptor antagonism, the upregulatory effect of succinic acid on NETs could be significantly blocked by SUCNR1 antagonist.

CONCLUSIONS

Succinic acid could worsen EAU induced by IRBP in mice. This effect was possibly mediated by its upregulation on NETs generation and frequencies of Th1/Th17 cells in affiliation with increased production of IFN-γ/IL-17A through succinic acid-SUCNR1 axis.

Advances in pathogenesis and treatment of ocular involvement in Behcet's disease

Behcet's disease (BD) is a chronic multi-systemic disease characterized by relapsing-remitting oral ulcers, genital ulcers, ocular inflammatory involvements, and numerous other systemic features. Ocular involvements are quite common in BD and may cause severe tissue damage and potentially blindness. Even though the pathogenesis of BD remains ambiguous, growing evidences have shown that genetic factors, environmental triggers and immunological abnormalities play significant roles in its development and progression. Novel biotherapies targeting IFN-γ, TNF-α and interleukins have been used in recent years. In this review, we mainly pay attention to the ocular involvement of BD, and discuss the current understanding of mechanisms and advances in therapeutic approaches, especially novel biologics. Finally, we discuss the management in patients with pregnancy.

Autoimmune uveitis in Behçet's disease and Vogt-Koyanagi-Harada disease differ in tissue immune infiltration and T cell clonality

Objectives

Non-infectious uveitis is often secondary to systemic autoimmune diseases, with Behçet's disease (BD) and Vogt-Koyanagi-Harada disease (VKHD) as the two most common causes. Uveitis in BD and VKHD can show similar clinical manifestations, but the underlying immunopathogenesis remains unclear.

Methods

To understand immune landscapes in inflammatory eye tissues, we performed single-cell RNA paired with T cell receptor (TCR) sequencing of immune cell infiltrates in aqueous humour from six patients with BD (N = 3) and VKHD (N = 3) uveitis patients.

Results

Although T cells strongly infiltrated in both types of autoimmune uveitis, myeloid cells only significantly presented in BD uveitis but not in VKHD uveitis. Conversely, VKHD uveitis but not BD uveitis showed an overwhelming dominance by CD4+ T cells (> 80%) within the T cell population due to expansion of CD4+ T cell clusters with effector memory (Tem) phenotypes. Correspondingly, VKHD uveitis demonstrated a selective expansion of CD4+ T cell clones which were enriched in pro-inflammatory Granzyme H+ CD4+ Tem cluster and showed TCR and Th1 pathway activation. In contrast, BD uveitis showed a preferential expansion of CD8+ T cell clones in pro-inflammatory Granzyme H+ CD8+ Tem cluster, and pathway activation for cytoskeleton remodelling, cellular adhesion and cytotoxicity.

Conclusion

Single-cell analyses of ocular tissues reveal distinct landscapes of immune cell infiltration and T-cell clonal expansions between VKHD and BD uveitis. Preferential involvements of pro-inflammatory CD4+ Th1 cells in VKHD and cytotoxic CD8+ T cells in BD suggest a difference in disease immunopathogenesis and can guide precision disease management.

Bibliometric analysis of the uveitis literature and research trends over the past two decades

OBJECTIVE

This study aimed to examine the publication patterns and present a current view of the field of uveitis using a bibliometric analysis.

DESIGN

Bibliometric analysis.

METHODS AND ANALYSIS

A comprehensive search of three databases including MEDLINE, EMBASE and Cochrane was conducted from 1 January 2000 to 31 December 2022. Search results from all three databases were subjected to analysis by Bibliometrix, an R programme that analyses large literature dataset with statistical and mathematical models. Visualisation of collaboration networks and relevance between countries was presented with VOSviewer.

RESULTS

A total of 26 296 articles were included in the analysis. The field of uveitis has undergone a significant exponential growth since 2000, with an average growth rate of 4.14%. The most substantial annual growth was between the years 2021 and 2022 (36%). According to the corresponding author's countries, the three most productive countries were Turkey (3288, 12.6%), the USA (3136, 12%) and Japan (1981, 7.6%). The USA (243, 31.4%), England (117, 15%) and Germany (62, 8%) are the top three countries that contributed to clinical trials. The average international collaboration of all countries was 2.5%.

CONCLUSIONS

Uveitis literature has undergone significant growth in the past two decades. The demographic factors of publishing countries lead to their various productivity and types of these uveitis studies, which is closely associated with the countries' scientific research resources and patient populations.

Targeting the Gut-Eye Axis: An Emerging Strategy to Face Ocular Diseases

The human microbiota refers to a large variety of microorganisms (bacteria, viruses, and fungi) that live in different human body sites, including the gut, oral cavity, skin, and eyes. In particular, the presence of an ocular surface microbiota with a crucial role in maintaining ocular surface homeostasis by preventing colonization from pathogen species has been recently demonstrated. Moreover, recent studies underline a potential association between gut microbiota (GM) and ocular health. In this respect, some evidence supports the existence of a gut-eye axis involved in the pathogenesis of several ocular diseases, including age-related macular degeneration, uveitis, diabetic retinopathy, dry eye, and glaucoma. Therefore, understanding the link between the GM and these ocular disorders might be useful for the development of new therapeutic approaches, such as probiotics, prebiotics, symbiotics, or faecal microbiota transplantation through which the GM could be modulated, thus allowing better management of these diseases.

Emerging roles of air pollution and meteorological factors in autoimmune eye diseases

Autoimmune eye diseases (AEDs), a collection of autoimmune inflammatory ocular conditions resulting from the dysregulation of immune system at the ocular level, can target both intraocular and periorbital structures leading to severe visual deficit and blindness globally. The roles of air pollution and meteorological factors in the initiation and progression of AEDs have been increasingly attractive, among which the systemic and local mechanisms are both involved in. Exposure to excessive air pollution and extreme meteorological conditions including PM2.5/PM0.1, environmental tobacco smoke, insufficient sunshine, and high temperature, etc., can disturb Th17/Treg balance, regulate macrophage polarization, activate neutrophils, induce systemic inflammation and oxidative stress, decrease retinal blood flow, promote tissue fibrosis, activate sympathetic nervous system, adversely affect nutrients synthetization, as well as induce heat stress, therefore may together deteriorate AEDs. The crosstalk among inflammation, oxidative stress and dysregulated immune system appeared to be prominent. In the present review, we will concern and summarize the potential mechanisms underlying linkages of air pollution and meteorological factors to ocular autoimmune and inflammatory responses. Moreover, we concentrate on the specific roles of air pollutants and meteorological factors in several major AEDs including uveitis, Graves' ophthalmopathy (GO), ocular allergic disease (OAD), glaucoma, diabetic retinopathy (DR), etc.

Pathogenesis and current therapies for non-infectious uveitis

Non-infectious uveitis (NIU) is a disorder with various etiologies and is characterized by eye inflammation, mainly affecting people of working age. An accurate diagnosis of NIU is crucial for appropriate therapy. The aim of therapy is to improve vision, relieve ocular inflammation, prevent relapse, and avoid treatment side effects. At present, corticosteroids are the mainstay of topical or systemic therapy. However, repeated injections are required for the treatment of chronic NIU. Recently, new drug delivery systems that may ensure intraocular delivery of therapeutic drug levels have been highlighted. Furthermore, with the development of immunosuppressants and biologics, specific therapies can be selected based on the needs of each patient. Immunosuppressants used in the treatment of NIU include calcineurin inhibitors and antimetabolites. However, systemic immunosuppressive therapy itself is associated with adverse effects due to the inhibition of immune function. In patients with refractory NIU or those who cannot tolerate corticosteroids and immunosuppressors, biologics have emerged as alternative treatments. Thus, to improve the prognosis of patients with NIU, NIU should be managed with different drugs according to the response to treatment and possible side effects.

γδ T cells in autoimmune uveitis pathogenesis: A promising therapeutic target

Autoimmune uveitis is a non-infectious, inflammatory intraocular disease that affects the uveal and adjacent tissues. It frequently causes varying degrees of visual loss. Evidence for the strong association between activated γδ T cells and the development of autoimmune uveitis is growing. The innate and adaptive immune response are connected in the early phases by the γδ T cells that contain the γ and δ chains. γδ T cells can identify antigens in a manner that is not constrained by the MHC. When activated by various pathways, γδ T cells can not only secrete pro-inflammatory factors early on (such as IL-17), but they can also promote Th17 cells responses, which ultimately exacerbates autoimmune uveitis. Therefore, we review the mechanisms by which γδ T cells affect autoimmune uveitis in different activation and disease states. Moreover, we also prospect for immunotherapies targeting different γδ T cell-related action pathways, providing a reference for exploring new drug for the treatment of autoimmune uveitis.

Rheumatologist's Perspective on Non-Infectious Uveitis: Patterns from Tertiary Referral Rheumatologic Clinics in Italy

Non-infectious uveitis (NIU) can be an early or even the first extra-articular manifestation of systemic rheumatic diseases, or the first one; thus, rheumatologists are often involved in the diagnostic and therapeutic assessment of NIU. We evaluated 130 patients with a diagnosis of NIU who were admitted to two Italian rheumatologic clinics (Tor Vergata University Hospital in Rome, and Federico II University in Naples) from January 2018 to December 2021. Anterior uveitis (AU) occurred in 75.4% of patients, followed by posterior uveitis (PU, 21.5%); acute (54.6%) and recurrent (35.4%) NIU were more documented than chronic NIU (10%), and a bilateral involvement was observed in 38.7% of cases. Half of NIU cases were associated with spondyloarthritis (SpA); the remaining were affected by Behçet disease (BD)-related uveitis (13.9%) and idiopathic NIU (9.2%). HLA-B27⁺ patients (34.8%) had a higher prevalence of anterior and unilateral NIU (p = 0.005) with acute course (p = 0.04) than HLA-B27^- patients. On the contrary, HLA-B51⁺ patients (19.6%) had mostly PU and bilateral NIU (p < 0.0001) and recurrent course (p = 0.04) than HLA-B51^- patients. At the first rheumatologic referral, 117 patients (90%) received systemic treatments. Findings from this study demonstrate that rheumatologic referral has a pivotal role in the diagnostic work-up of NIU and may dramatically influence NIU-treatment strategies.

Noninfectious Uveitis in Rheumatology: Patterns, Treatment, and Outcomes

OBJECTIVES

The present study aimed to determine the pattern and cause of noninfectious uveitis in rheumatology practice. The secondary objective was to identify the pattern of treatment and outcomes.

MATERIALS AND METHODS

This retrospective cross-sectional study was conducted in the Department of Rheumatology, National Hospital and Medical Centre, Lahore, Pakistan. After receiving consent, electronic medical records (EMRs) of all patients with a diagnosis of noninfectious uveitis (NIU) from November 2019 to January 2023 were reviewed, and a total of 52 patients labeled as having noninfectious uveitis were identified. The collected data included age at diagnosis, anatomical location of uveitis, associated systemic disease, used medications, and outcomes. All cases had been diagnosed and assessed mutually by a rheumatologist and an ophthalmologist using the International Uveitis Study Group classification system to classify the pattern of uveitis by location, clinical course, and laterality and rule out the possibility of other ophthalmologic diseases. Disease activity was defined using the Standardization of Uveitis Nomenclature (SUN) guidelines. Data was analyzed on SPSS Statistics version 23 (IBM Corp, Armonk, NY, USA).

RESULTS

The mean age of the patients in this study was 36.02 ± 43.31 years, with 31 (59.6%) male patients. Anterior uveitis was the most common type observed among the patients at 55.8%, panuveitis was found in 25%, intermediate uveitis and posterior uveitis were seen in 9.6% each. Based on laterality, unilateral eye involvement was identified in 53.8% of patients. Spondyloarthritis (SpA) and idiopathic uveitis were observed in 34.6% and 28.8%, respectively. In this study, 28 (54.9%) patients were on conventional disease-modifying antirheumatic drugs (cDMARDDs), and 23 (45.1%) were on biological DMARDs. In the biologics group, 82% of patients were in remission in comparison to 60% in the cDMARDs group.

CONCLUSION

To the best of our knowledge, this is the first report on noninfectious uveitis in the Pakistani population. The study concluded that anterior uveitis is the most common type of uveitis and is more common in males. Spondyloarthropathy is one of the most common underlying systemic diseases. Human leukocyte antigen (HLA)-B27 is associated more with uveitis. Biologics are more effective than cDMARDs in controlling the disease. Collaborative work between different specialties resulted in early diagnosis of underlying systemic disease, better management plans, and disease outcomes. To obtain further details on noninfectious uveitis, a population-based study is needed in Pakistan.

[Noninfectious posterior uveitis : Clinical aspects, diagnostics, management and treatment]

Noninfectious posterior uveitis (NPU) comprises a heterogeneous group of vision-threatening, immune-mediated ocular and systemic diseases. It is predominantly bilateral and recurrent and, if not treated properly, leads to severe tissue damage that threatens the eyesight. In industrialized countries ca. 10-20% of all cases of blindness are caused by NPU. An NPU can occur at any age but is most common between the ages of 20 and 50 years. Laboratory diagnostic and imaging procedures enable an increasingly better differentiation of the disease spectrum. This makes it possible to better assess the course and prognosis of individual disease entities. An increasing repertoire of systemic and intravitreal forms of treatment has already led to more favorable long-term treatment outcomes. It can be expected that further progress can be achieved with better knowledge of the pathophysiology of the different clinical disorders and appropriate, targeted treatment.

Study of the shared gene signatures of polyarticular juvenile idiopathic arthritis and autoimmune uveitis

Objective

To explore the shared gene signatures and potential molecular mechanisms of polyarticular juvenile idiopathic arthritis (pJIA) and autoimmune uveitis (AU).

Method

The microarray data of pJIA and AU from the Gene Expression Omnibus (GEO) database were downloaded and analyzed. The GEO2R tool was used to identify the shared differentially expressed genes (DEGs) and genes of extracellular proteins were identified among them. Then, weighted gene co-expression network analysis (WGCNA) was used to identify the shared immune-related genes (IRGs) related to pJIA and AU. Moreover, the shared transcription factors (TFs) and microRNAs (miRNAs) in pJIA and AU were acquired by comparing data from HumanTFDB, hTFtarget, GTRD, HMDD, and miRTarBase. Finally, Metascape and g: Profiler were used to carry out function enrichment analyses of previously identified gene sets.

Results

We found 40 up-regulated and 15 down-regulated shared DEGs via GEO2R. Then 24 shared IRGs in positivity-related modules, and 18 shared IRGs in negatively-related modules were found after WGCNA. After that, 3 shared TFs (ARID1A, SMARCC2, SON) were screened. And the constructed TFs-shared DEGs network indicates a central role of ARID1A. Furthermore, hsa-miR-146 was found important in both diseases. The gene sets enrichment analyses suggested up-regulated shared DEGs, TFs targeted shared DEGs, and IRGs positivity-correlated with both diseases mainly enriched in neutrophil degranulation process, IL-4, IL-13, and cytokine signaling pathways. The IRGs negatively correlated with pJIA and AU mainly influence functions of the natural killer cell, cytotoxicity, and glomerular mesangial cell proliferation. The down-regulated shared DEGs and TFs targeted shared DEGs did not show particular functional enrichment.

Conclusion

Our study fully demonstrated the flexibility and complexity of the immune system disorders involved in pJIA and AU. Neutrophil degranulation may be considered the shared pathogenic mechanism, and the roles of ARID1A and MiR-146a are worthy of further in-depth study. Other than that, the importance of periodic inspection of kidney function is also noteworthy.

Causal Association between Iritis or Uveitis and Glaucoma: A Two-Sample Mendelian Randomisation Study

Recent studies have suggested an association between iritis or uveitis and glaucoma. This study investigated the causal relationship between glaucoma and iritis and uveitis as exposures in a multi-ethnic population. Single-nucleotide polymorphisms associated with exposures to iritis and uveitis from the genome-wide association study (GWAS) data of Biobank Japan (BBJ) and the meta-analysis data from BBJ and UK Biobank (UKB) were used as instrumental variables (IVs). The GWAS dataset for glaucoma was extracted from the meta-analysis data (n = 240,302) of Genetic Epidemiology Research in Adult Health and Aging and UKB. The casual estimates were assessed with a two-sample Mendelian randomisation (MR) test using the inverse-variance-weighted (IVW) method, weighted median method, MR–Egger method, and MR-Pleiotropy Residual Sum and Outlier test. The IVW method revealed a significant causal association between iritis and glaucoma using IVs (p < 5.0 × 10−8) from the East Asian population (n = 2) (odds ratio [OR] = 1.01, p = 0.017), a significant association between iritis exposures (p < 5.0 × 10−8) in the multi-ethnic population (n = 11) (OR = 1.04, p = 0.001), and a significant causal association between uveitis exposures (n = 10 with p < 5.0 × 10−8) and glaucoma in the multi-ethnic population (OR = 1.04, p = 0.001). Iritis and uveitis had causal effects on glaucoma risk based on IVs from the multi-ethnic population. These findings imply that the current classifications of uveitic glaucoma and open-angle glaucoma overlap, indicating the need for further investigating these complex relationships.

Prednisone acetate modulates Th1/Th2 and Th17/Treg cell homeostasis in experimental autoimmune uveitis via orchestrating the Notch signaling pathway

Uveitis is an immune eye disease that can seriously impair vision. Glucocorticoids (GC_S) have been extensively used to treat uveitis, though the mechanisms have not been fully elucidated. In this study, we investigated the regulatory effects of prednisone acetate (PA) on the Th1/Th2 and Th17/Treg balance in experimental autoimmune uveitis (EAU) through modulating the Notch signaling pathway. Briefly, Lewis rats were randomly divided into the normal control (NC), EAU, and EAU + PA groups. Rats in EAU and EAU + PA groups were induced EAU, while those in the EAU + PA group were treated with PA. Clinical and histopathological scores were employed to assess the progression of EAU. The expression levels of Notch signaling-related molecules (Notch1, Notch2, Dll3, Dll4, and Rbpj) and Th-associated cytokines (IFN-γ, IL-4, IL-10, and IL-17) were assessed via quantitative PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA). In addition, the frequencies of Th1, Th2, Th17 and Treg cells were detected by flow cytometry. These experimental results indicated that activation of the Notch signaling pathway occurred in EAU rats and resulted in a severe imbalance of the Th17/Treg and Th1/Th2 ratios. PA treatment significantly alleviated ocular inflammation, inhibited activation of the Notch signaling pathway, and declined Th1, and Th17 cell differentiation, thereby restoring the Th1/Th2 and Th17/Treg balance. Collectively, PA can positively enhance the systemic immune response and improve the intraocular microenvironmental homeostasis by inhibiting activation of the Notch signaling pathway and by restoring Th1/Th2 and Th17/Treg balance, thus achieving the goal of treating uveitis.

Genetic association of PRKCD and CARD9 polymorphisms with Vogt-Koyanagi-Harada disease in the Chinese Han population

BACKGROUND

Protein kinase C delta (PRKCD) and caspase recruitment domain family member 9 (CARD9) are genes involved in B and T cell activation, and cytokine production, which are vital mechanisms underlying autoimmune disease development. This study aimed to explore the association of the PRKCD and CARD9 genes with Vogt-Koyanagi-Harada disease (VKH) disease. The case-control study was performed to in 912 patients with VKH and 878 normal controls. MassARRAY system, SHEsis online platform, real-time PCR, and enzyme-linked immunosorbent assay were used to detect genotyping, haplotyping, mRNA expression, and cytokine levels, respectively.

RESULTS

We found that rs74437127 C allele of PRKCD, rs3812555 CC genotype, and C allele of CARD9 were associated with increased susceptibility of VKH (Pc = 0.020, OR = 1.624; Pc = 2.04 × 10^-5, OR = 1.810; Pc = 2.76 × 10^-5, OR = 1.698, respectively). However, the rs74437127 T allele, and rs3812555 TC genotype and T allele were linked with decreased susceptibility to VKH (Pc = 0.020, OR = 0.616; Pc = 7.85 × 10^-5, OR = 0.559; Pc = 2.76 × 10^-5, OR = 0.589, respectively). PRKCD ATG and CARD9 GCTTA haplotypes decreased susceptibility to VKH (Pc = 3.11 × 10^-3, OR = 0.594; Pc = 5.00 × 10^-3, OR = 0.639, respectively). Functional studies on rs3812555 genotyped individuals revealed that CC carriers had significantly higher CARD9 mRNA expression and tumour necrosis factor-α production than TC/TT carriers (P = 1.00 × 10^-4; P = 2.00 × 10^-3, respectively).

CONCLUSIONS

We found an association between PRKCD rs74437127 and CARD9 rs3812555 polymorphisms and VKH susceptibility and revealed that the increased susceptibility of rs3812555 for VKH may be mediated by regulating CARD9 gene expression and the production of pro-inflammatory cytokines, such as TNF-α.

SNP rs7130280 in lncRNA NONHSAT159216.1 confers susceptibility to Behçet's disease uveitis in a Chinese Han population

OBJECTIVE

Long noncoding RNA (lncRNA) plays a crucial role in the process of immune-mediated diseases. However, the defined involvement of lncRNA on Behçet's disease (BD) is not well known. The aim of this study was to investigate the effects of lncRNA-related single nucleotide polymorphisms (SNPs) on BD susceptibility in Chinese populations.

METHODS

A two-stage case-control association study was conducted in a cohort of 1152 BD individuals and 1152 healthy controls. Genotyping was performed by a MassARRAY System. Quantified expression of the lncRNA-miRNA-mRNA molecular axis was detected by real-time PCR and western blot. The cell proliferation was measured by CCK-8 assay.

RESULTS

Two-stage association analysis showed a significantly decreased frequency of A allele of SNP rs7130280 in BD patients compared with healthy controls [OR 0.72 (95% CI 0.64, 0.81), Pc = 1.15 × 10-6]. Functionally, SNP rs7130280 could influence the secondary structure and relative expression of NONHSAT159216.1 in human THP-1/U937 macrophages and in peripheral blood mononuclear cells from healthy volunteers. In vitro, overexpression of the rs7130280 A allele also suppressed cell proliferation. Mechanistically, rs7130280 A allele could inhibit the expression of miR-6778-5p, thus enhancing its downstream molecular RPS6KA4/IL10 in a competing endogenous RNA sponge manner.

CONCLUSION

Our findings suggest that NONHSAT159216.1 rs7130280 G>A might be associated with a low risk of BD and participates in a potential lncRNA-miRNA-mRNA regulatory network.

Clinical Comparative Study of Different Fundus Imaging Methods in the Acute Phase of Vogt-Koyanagi-Harada Disease

BACKGROUND

The diversification of follow-up ophthalmic imaging examination methods, and whether there are differences in clinical characteristics of VKH at the acute stage under different images. Our study aims to compare the imaging characteristics of the acute phase of Vogt-Koyanagi-Harada disease (VKH) under different fundus imaging methods to deepen clinical knowledge.

METHODS

A retrospective case study was performed on fundus images of 62 eyes from 31 patients with acute phase VKH and a disease duration ≤2 months who were treated at Ganzhou People's Hospital from January 2013 to December 2020. Fundus photography (FP), optical coherence tomography (OCT), and fundus fluorescein angiography (FFA) were performed on all 62 eyes. The fundus presentations were divided into an optic disc swelling (ODS) group, a serous retinal detachment (SRD) group, and a mixed type (MT) group (both ODS and SRD), and the proportions of patients in these groups and the coincidence rate of ODS, SRD, and MT identified by the three fundus imaging modes were determined.

RESULTS

The proportion of patients with ODS was highest under FP, and the proportion of patients with MT was highest under OCT. The proportions of patients with ODS and MT in the three fundus imaging modes differed significantly (P < 0.05), while the proportion of patients with SRD did not (P > 0.05). The proportion of patients with subretinal fluid with positive OCT results was significantly higher than those with positive FFA results (81.08% vs. 59.46%) (P < 0.05).

CONCLUSION

Clinically significant positive signs could be obtained for acute VKH under different imaging methods. However, compared with FP and FFA, OCT tomography is more intuitive for the observation of lesions.

Identification of uveitis-associated functions based on the feature selection analysis of gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment scores

Uveitis is a typical type of eye inflammation affecting the middle layer of eye (i.e., uvea layer) and can lead to blindness in middle-aged and young people. Therefore, a comprehensive study determining the disease susceptibility and the underlying mechanisms for uveitis initiation and progression is urgently needed for the development of effective treatments. In the present study, 108 uveitis-related genes are collected on the basis of literature mining, and 17,560 other human genes are collected from the Ensembl database, which are treated as non-uveitis genes. Uveitis- and non-uveitis-related genes are then encoded by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment scores based on the genes and their neighbors in STRING, resulting in 20,681 GO term features and 297 KEGG pathway features. Subsequently, we identify functions and biological processes that can distinguish uveitis-related genes from other human genes by using an integrated feature selection method, which incorporate feature filtering method (Boruta) and four feature importance assessment methods (i.e., LASSO, LightGBM, MCFS, and mRMR). Some essential GO terms and KEGG pathways related to uveitis, such as GO:0001841 (neural tube formation), has04612 (antigen processing and presentation in human beings), and GO:0043379 (memory T cell differentiation), are identified. The plausibility of the association of mined functional features with uveitis is verified on the basis of the literature. Overall, several advanced machine learning methods are used in the current study to uncover specific functions of uveitis and provide a theoretical foundation for the clinical treatment of uveitis.

Comprehensive Proteomic Profiling of Vitreous Humor in Ocular Sarcoidosis Compared with Other Vitreoretinal Diseases

Ocular sarcoidosis is an inflammatory disease that manifests as uveitis, and is often difficult to distinguish from other forms of uveitis based on nonspecific findings alone. Comprehensive proteomic analyses of vitreous humor using LC-MS/MS were performed in each patient with ocular sarcoidosis, vitreoretinal lymphoma (VRL), and controls with epiretinal membrane or macular hole. Differential expression proteins (DEPs) were identified by comparing with VRL and controls, and functional pathway analysis was performed. The candidate biomarker proteins for ocular sarcoidosis were validated using enzyme-linked immunosorbent assay. A total of 1590 proteins were identified in all samples. Of these, 290 and 174 DEPs were detected in vitreous of ocular sarcoidosis compared with controls and VRL, respectively. Enrichment pathway analysis revealed that pathways related to the immune system were most upregulated. Validation of two candidate biomarkers for ocular sarcoidosis, neutrophil gelatinase-associated lipocalin (NGAL) and junctional adhesion molecules B (JAMB), confirmed upregulated NGAL and JAMB protein expressions in ocular sarcoidosis compared to controls and VRL. The results of this study revealed that altered vitreous protein expression levels may discriminate ocular sarcoidosis from other uveitis diseases. Vitreous NGAL and JAMB are potential biomarkers and may serve as an auxiliary tool for the diagnosis of ocular sarcoidosis.

Association between meteorological factors and hospital admissions for uveitis in Hefei, China: a time-series study

Meteorological variables are regarded as risk factors for inflammatory diseases, but their associations with uveitis, one of the leading causes accounting for blindness worldwide with an estimated prevalence of 38-714 cases/100,000 person-years, have not been thoroughly investigated. The present study explored the short-term association between meteorological variables and hospital admissions for uveitis in Hefei City, China. Daily data on uveitis hospital admissions and meteorological variables including mean temperature (MT) (°C), diurnal temperature range (DTR) (°C), and relative humidity (RH) (%), from 2014 to 2020, were collected. A time-series study using generalized linear model combined with distributed lag non-linear model was applied. Totally, 1911 admissions for uveitis including 894 first admissions and 1017 readmissions were reported during the study period. The associations of high percentile of MT (75th, 24.5℃) and low percentile of DTR (25th, 5.4℃) with uveitis admissions were observed to be statistically significant from lag9 (RR = 1.041, 95%CI: 1.002-1.081) to lag11 (RR = 1.053, 95%CI: 1.003-1.104) and lag4 (RR = 1.053, 95%CI: 1.019-1.088) to lag5 (RR = 1.052, 95%CI: 1.020-1.085), respectively. Moreover, a significant association between low percentile of RH (1th, 44%) and uveitis admissions appeared at lag0-8 (RR = 1.869, 95%CI: 1.017-3.434) and lasted until lag0-13 (RR = 2.539, 95%CI: 1.102-5.850) in the cumulative lag structure. Subgroup analyses indicated that males and the young seemed to be more sensitive to high MT exposure, while females appeared to be more vulnerable to low DTR exposure. Interestingly, both the young and the elderly are susceptible to low DTR and low RH exposure. Furthermore, high MT and low DTR exposure were associated with increased risk of first admission for uveitis. In summary, exposure to high-value of MT and low-value of DTR and RH may increase the hospital admissions for uveitis, especially for the status of first admission.

The HLA-G Immune Checkpoint Plays a Pivotal Role in the Regulation of Immune Response in Autoimmune Diseases

The human G-leukocyte antigen (HLA-G) molecule is a non-classical major histocompatibility complex (MHC) class I molecule. The pertinence of HLA-G has been investigated in numerous studies which have sought to elucidate the relevance of HLA-G in pathologic conditions, such as autoimmune diseases, cancers, and hematologic malignancies. One of the main goals of the current research on HLA-G is to use this molecule in clinical practice, either in diagnostics or as a therapeutic target. Since HLA-G antigens are currently considered as immunomodulatory molecules that are involved in reducing inflammatory and immune responses, in this review, we decided to focus on this group of antigens as potential determinants of progression in autoimmune diseases. This article highlights what we consider as recent pivotal findings on the immunomodulatory function of HLA-G, not only to establish the role of HLA-G in the human body, but also to explain how these proteins mediate the immune response.