The role of tumour necrosis factor (TNF-alpha) in experimental autoimmune uveoretinitis (EAU)

Long-term Experience with Anti-tumor Necrosis factor - α Therapy in the Treatment of Refractory, Non-infectious Intermediate, Posterior, and Panuveitis

PURPOSE

To study the efficacy and long-term effects of infliximab and adalimumab in patients with active refractory non-infectious intermediate, posterior, or panuveitis (NIPPU).

METHODS

Retrospective, longitudinal study.

RESULTS

Included were 61 patients (104 eyes) of whom 34 were males (55.74%). Mean age at diagnosis of uveitis was 26.5 ± 16.14 years. All patients had active uveitis at baseline (time of initiation of biological therapy). Median interval between the start of conventional immunomodulatory therapy (IMT) to the introduction of biological therapy was 13.0 (IQR 26.0) months. Ocular inflammation was effectively controlled in 92 eyes (88.46%). The most commonly used TNF-α inhibitor was adalimumab in 47 patients (77%). Mean follow-up time after baseline was 40 ± 34.08 months. In the year preceding the institution of TNF-α inhibitors, the average number of flares was 1.5 ± 1.1/year and it decreased to 0.08 ± 0.29/year in the first year after baseline (p < .0005). Forty-four eyes (42.30%) experienced flare over the entire follow-up period. Mean time to first flare was 14.5 ± 9.26 months. At baseline, the mean dose of prednisone was 25.5-±20.8 mg/day. A marked decrease to a mean prednisone dose of 7.85 ± 9.7 mg/day was observed at 6 months (p = .03). In patients treated with adalimumab, the mean time to prednisone dose ≤7.5 mg/day was 4.02 ± 4.89 months compared to 15.64 ± 21.34 months in patients treated with infliximab (p = .03). 64.3% of patients treated by infliximab had Behçet uveitis compared to 27.7% of patients treated by adalimumab. Eyes treated with adalimumab experienced first flare at a mean time of 14.11 ± 6.29 months, whereas eyes treated with infliximab experienced first flare at 18.29 ± 14.24 months after baseline (p < .0005). The risk for moderate and severe visual loss was lower with shorter duration of uveitis before initiating anti-TNF-α treatment (odds ratio, 0.003; 95% CI, 0.000-0.005; p = .023), better presenting logMAR VA (odds ratio, 0.266; 95% CI, 0.172-0.361; p < .0005) and when adalimumab was used (odds ratio, 0.354; 95% CI, 0.190-0.519, p < .0005).

CONCLUSIONS

Anti-TNF-α therapy was successful in controlling refractory NIPPU in the majority of cases. It significantly reduced flare rate, exerted steroid-sparing effects, and preserved visual potential. Adalimumab use, better initial visual acuity, and earlier introduction of anti-TNF- α therapy were associated with a lower risk of visual loss.

Microglial mediators in autoimmune Uveitis: Bridging neuroprotection and neurotoxicity

Autoimmune uveitis, a severe inflammatory condition of the eye, poses significant challenges due to its complex pathophysiology and the critical balance between protective and detrimental immune responses. Central to this balance are microglia, the resident immune cells of the central nervous system, whose roles in autoimmune uveitis are multifaceted and dynamic. This review article delves into the dual nature of microglial functions, oscillating between neuroprotective and neurotoxic outcomes in the context of autoimmune uveitis. Initially, we explore the fundamental aspects of microglia, including their activation states and basic functions, setting the stage for a deeper understanding of their involvement in autoimmune uveitis. The review then navigates through the intricate mechanisms by which microglia contribute to disease onset and progression, highlighting both their protective actions in immune regulation and tissue repair, and their shift towards a pro-inflammatory, neurotoxic profile. Special emphasis is placed on the detailed pathways and cellular interactions underpinning these dual roles. Additionally, the review examines the potential of microglial markers as diagnostic and prognostic indicators, offering insights into their clinical relevance. The article culminates in discussing future research directions, and the ongoing challenges in translating these findings into effective clinical applications. By providing a comprehensive overview of microglial mechanisms in autoimmune uveitis, this review underscores the critical balance of microglial activities and its implications for disease management and therapy development.

Natural plant medications for the treatment of retinal diseases: The blood-retinal barrier as a clue

BACKGROUND

Retinal diseases significantly contribute to the global burden of visual impairment and blindness. The occurrence of retinal diseases is often accompanied by destruction of the blood‒retinal barrier, a vital physiological structure responsible for maintaining the stability of the retinal microenvironment. However, detailed summaries of the factors damage the blood‒retinal barrier and treatment methods involving natural plant medications are lacking.

PURPOSE

To comprehensively summarize and analyze the protective effects of active substances in natural plant medications on damage to the blood-retina barrier that occurs when retinal illnesses, particularly diabetic retinopathy, and examine their medicinal value and future development prospects.

METHODS

In this study, we searched for studies published in the ScienceDirect, PubMed, and Web of Science databases. The keywords used included natural plant medications, plants, natural herbs, blood retinal barrier, retinal diseases, diabetic retinopathy, age-related macular degeneration, and uveitis. Chinese herbal compound articles, non-English articles, warning journals, and duplicates were excluded from the analysis.

RESULTS

The blood‒retinal barrier is susceptible to high glucose, aging, immune responses, and other factors that destroy retinal homeostasis, resulting in pathological changes such as apoptosis and increased vascular permeability. Existing studies have shown that the active compounds or extracts of many natural plants have the effect of repairing blood-retinal barrier dysfunction. Notably, berberine, puerarin, and Lycium barbarum polysaccharides exhibited remarkable therapeutic effects. Additionally, curcumin, astragaloside IV, hesperidin, resveratrol, ginsenoside Rb1, luteolin, and Panax notoginseng saponins can effectively protect the blood‒retinal barrier by interfering with distinct pathways. The active ingredients found in natural plant medications primarily repair the blood‒retinal barrier by modulating pathological factors such as oxidative stress, inflammation, pyroptosis, and autophagy, thereby alleviating retinal diseases.

CONCLUSION

This review summarizes a series of plant extracts and plant active compounds that can treat retinal diseases by preventing and treating blood‒retinal barrier damage and provides reference for the research of new drugs for treating retinal diseases.

Aqueous Macrophages Contribute to Conserved CCL2 and CXCL10 Gradients in Uveitis

Purpose

Uveitis is a heterogenous group of inflammatory eye disease for which current cytokine-targeted immune therapies are effective for only a subset of patients. We hypothesized that despite pathophysiologic nuances that differentiate individual disease states, all forms of eye inflammation might share common mechanisms for immune cell recruitment. Identifying these mechanisms is critical for developing novel, broadly acting therapeutic strategies.

Design

Experimental study.

Subjects

Biospecimens from patients with active or inactive uveitis and healthy controls.

Methods

Protein concentration and single cell gene expression were assessed in aqueous fluid biopsies and plasma samples from deidentified patients with uveitis or healthy controls.

Main Outcome Measures

The concentration of 31 inflammatory proteins was measured in all aqueous samples, as well as plasma samples from patients with active uveitis. Chemokine and cytokine ligand and receptor expression were assessed in individual cell types from aqueous biopsies obtained from patients with active uveitis.

Results

We identified 6 chemokines that were both elevated in active uveitis compared with controls and enriched in aqueous compared with plasma during active uveitis (C-C motif chemokine ligand [CCL]2, C-X-C motif chemokine ligand [CXCL]10, CXCL9, CXCL8, CCL3, and CCL14), forming potential gradients for migration of immune cells from the blood to the eye. Of these, CCL2 and CXCL10 were consistently enriched in the aqueous of all patients in our cohort, as well as in a larger cohort of patients from a previously published study. These data suggest that CCL2 and CXCL10 are key mediators in immune cell migration to the eye during uveitis. Next, single cell RNA sequencing suggested that macrophages contribute to aqueous enrichment of CCL2 and CXCL10 during human uveitis. Finally, using chemokine ligand and receptor expression mapping, we identified a broad signaling network for macrophage-derived CCL2 and CXCL10 in human uveitis.

Conclusions

These data suggest that ocular macrophages may play a central role, via CCL2 and CXCL10 production, in recruiting inflammatory cells to the eye in patients with uveitis.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Design and Development of a Web-Based Prospective Nationwide Registry for Ocular Inflammatory Diseases: UVEITE.PT - The Portuguese Ocular Inflammation Registry

Uveitis is a heterogeneous collection of infrequent diseases, which poses significant challenges to cost-effective research in the field. Medical registries are being increasingly recognized as crucial tools to provide high-quality data, thus enabling prospective clinical research. This paper describes the design and technical structure development of an innovative countrywide electronic medical record for uveitis, Uveite.pt, and gives an overview of the cohort registered since its foundation, March 2020.Uveite.pt is an electronic medical record platform developed by the Portuguese Ocular Inflammation Group (POIG), a scientific committee of the Portuguese Ophthalmology Society. This is a nationwide customized web-based platform for uveitis patients useful for both clinical practice and real-world-based research, working as a central repository and reporting tool for uveitis. This paper describes the technical principles, the design and the development of a web-based interoperable registry for uveitis in Portugal and provides an overview of more than 400 patients registered in the first 18 months since inception.In infrequent diseases, the existence of registries enables to gather evidence and increase research possibilities to clinicians. The adoption of this platform enables standardization and improvement of clinical practice in uveitis. It is useful to apprehend the repercussion of medical and surgical treatments in uveitis and scleritis, supporting clinicians in the strict monitoring of drug adverse reactions and surgical outcomes.

Effects of tumor necrosis factor-α and interleukin-1β on human retinal endothelial cells

Uveitis, or intraocular inflammation, is a potentially blinding condition that mostly affects the working-age population. The cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β, play a role in the pathogenesis of non-infectious uveitis and have been linked to the breakdown of the inner blood-retinal barrier, composed mainly of retinal endothelial cells, leading to macular oedema and vascular leakage. However, the effects of TNF-α and IL-1β on human retinal endothelial function are not fully understood. In this work, we investigated the impact of TNF-α and IL-1β on several aspects of human retinal endothelial cell biology. Through a real-time biosensor, the impact of TNF-α and IL-1β on formation of a retinal endothelial cell barrier was analyzed. Changes in junctional components were assessed via RT-qPCR and immunolabelling. Cell survival, necrosis and apoptosis were appraised via cell proliferation and flow cytometric studies. Tumor necrosis factor-α and IL-1β impaired the electrical resistance of the retinal endothelial cell barrier, while the addition of a potentially barrier-impairing cytokine, IL-6, did not enhance the effect of TNF-α and IL-1β. Level of the gene transcript encoding zonula occludens (ZO)-1 was diminished, while ZO-1 protein configuration was changed by TNF-α and IL-1β. Both cytokines affected human retinal endothelial cell proliferation and viability, while only TNF-α increased rates of necrosis. These results indicate that TNF-α and IL-1β are important drivers of retinal endothelial dysfunction in non-infectious uveitis, suggesting that targeting these cytokines is critical when treating complications of uveitis, such as macular oedema and vascular leakage.

Efficacy and Safety of Adalimumab in Patients with Behçet Uveitis: A Systematic Review and Meta-Analysis

PURPOSE

To examine the long-term efficacy and safety of adalimumab (ADA) in patients with Behçet uveitis (BU).

METHODS

A systematic review and meta-analysis of observational studies was performed. Pooled results are presented as mean difference or standardized mean difference (std diff) and 95% confidence intervals (CI). Visual acuity (VA), intraocular inflammation grade, central macular thickness, corticosteroid (CS) sparing effect and adverse events were evaluated.

RESULTS

Ten studies were included finally for quantitative and qualitative synthesis. ADA therapy resulted in 0.124 (95%CI: 0.084, 0.165) logMAR improvement in VA. In addition, ADA therapy resulted in decreased grade of intraocular inflammation [std diff, -1.187 (95%CI: -1.508, -0.866)] and macular thickness [std diff, -0.564 (95%CI: -0.843, -0.286)] and caused a decrease in CS dosage [std diff, -1.809 (95%CI: -2.420, -1.198)]. The pooled rate of overall adverse events for ADA in 301 patients was 8.5% (95%CI: 0.039, 0.177).

CONCLUSION

ADA is an efficient therapy that improves VA and controls intraocular inflammation, macular edema and retinal vasculitis. As the disease exposure time increased, improvement in VA was less. The safety and CS-sparing effect of ADA were demonstrated with few adverse effects. The results provided evidence that ADA can be used safely and efficiently as the first-line drug in patients with BU.

Inflammatory cytokines as mediators of retinal endothelial barrier dysfunction in non-infectious uveitis

Characterised by intraocular inflammation, non-infectious uveitis includes a large group of autoimmune and autoinflammatory diseases that either involve the eye alone or have both ocular and systemic manifestations. When non-infectious uveitis involves the posterior segment of the eye, specifically the retina, there is substantial risk of vision loss, often linked to breakdown of the inner blood-retinal barrier. This barrier is formed by non-fenestrated retinal vascular endothelial cells, reinforced by supporting cells that include pericytes, Müller cells and astrocytes. Across the published literature, a group of inflammatory cytokines stand out as prominent mediators of intraocular inflammation, with effects on the retinal endothelium that may contribute to breakdown of the inner blood-retinal barrier, namely tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, IL-17 and chemokine C-C motif ligand (CCL)2. This article reviews the function of each cytokine and discusses the evidence for their involvement in retinal endothelial barrier dysfunction in non-infectious uveitis, including basic laboratory investigations, studies of ocular fluids collected from patients with non-infectious uveitis, and results of clinical treatment trials. The review also outlines gaps in knowledge in this area. Understanding the disease processes at a molecular level can suggest treatment alternatives that are directed against appropriate biological targets to protect the posterior segment of eye and preserve vision in non-infectious uveitis.

Involvement of Angiopoietin 2 and vascular endothelial growth factor in uveitis

PURPOSE

Angiopoietin (Ang) 2 is released from vascular endothelial cells by the stimulation of vascular endothelial growth factor (VEGF)A. Ang2 increases the expression of leukocyte adhesion molecules on endothelial cells via nuclear factor κB. The aim of this study was to evaluate the effects of Ang2 and VEGFA on ocular autoimmune inflammation.

METHODS

We measured the concentrations of Ang2 and VEGFA in vitreous samples among patients with uveitis. Vitreous samples were collected from 16 patients with idiopathic uveitis (uveitis group) and 16 patients with non-inflammatory eye disease (control group). Experimental autoimmune uveoretinitis (EAU) was induced in B10.BR mice with a human interphotoreceptor retinoid-binding protein-derived peptide. The retinochoroidal tissues of the EAU mice were removed, and the mRNA levels of Ang2 and VEGFA were examined. EAU mice treated with anti-Ang2, anti-VEGFA, a combination of anti-Ang2 and anti-VEGFA, anti-Ang2/VEGFA bispecific, or IgG control antibodies were clinically and histopathologically evaluated.

RESULTS

The protein levels of Ang2 and VEGFA were significantly higher in the vitreous samples of patients with uveitis than in controls (P<0.05). The retinochoroidal mRNA levels of Ang2 and VEGFA were significantly upregulated in EAU mice compared to controls (n = 6, P<0.05). Although there was no significant difference, treatment with anti-VEGFA antibody reduced the clinical and histopathological scores. However, treatment with anti-Ang2 antibody reduced the clinical and histopathological scores (n = 18-20, P<0.05). Furthermore, these scores were further decreased when treated by inhibiting both Ang2 and VEGFA.

CONCLUSIONS

Based on these results, VEGFA and Ang2 were shown to be upregulated locally in the eye of both uveitis patients and models of uveitis. Dual inhibition of Ang2 and VEGFA is suggested to be a new therapeutic strategy for uveitis.

Melatonin attenuates lipopolysaccharide-induced immune dysfunction in dendritic cells

Melatonin, a ubiquitous hormone, is principally secreted from pineal gland in mammals and possesses strong antioxidant and anti-inflammatory properties. However, its specific roles in the immune functions of dendritic cells (DCs) during acute lung injury (ALI) remain unknown. In this study, we found that melatonin restored the body weight, decreased the lung weight/body weight ratio, alleviated the histopathological lung injury, and decreased the levels of cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-12p70, IL-17, and IL-10) in bronchoalveolar lavage fluid of the lipopolysaccharide (LPS)-induced ALI murine model. Moreover, melatonin inhibited the major histocompatibility complex II (MHCII) expression of lung CD11b⁺ DCs after LPS challenge in vivo. In vitro, melatonin reversed the shape index, promoted the endocytosis, and inhibited phenotypic expression of MHCII, CD40, CD80, and CD86 in LPS-activated DCs. Furthermore, melatonin decreased the expression of an activated marker, CD69, and the secretion of pro-inflammatory cytokines (TNF-α, IL-12p70, and IL-17) after LPS challenge. It hampered the LPS-activated DCs migration by downregulating the C-C chemokine receptor 7 (CCR7) expression, and then weakened the ability of LPS-induced DCs to stimulate allogeneic CD4⁺ T cell proliferation. Melatonin shaped the immune function of DCs in a nuclear factor erythroid-2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) axis-dependent manner. These findings indicate that melatonin protects DCs from ALI-induced immunological stress and may be used to develop novel DC-targeting strategies for ALI therapy.

Anti-adalimumab Antibodies in Patients with Non-infectious Ocular Inflammatory Disease: A Case Series

PURPOSE

To report the clinical course of patients with ocular inflammatory disease treated with adalimumab in whom anti-adalimumab antibodies (AAA) were detected.

METHODS

Single center case series.

RESULTS

Eight patients with initial response to adalimumab developed a disease flare associated with positive AAA testing after 5 to 76 months of therapy. Six patients were receiving no concurrent antimetabolite therapy at the time of AAA diagnosis and four had a temporary lapse in adalimumab therapy prior to AAA discovery. AAA resulted in undetectable drug levels in five of the seven patients for whom data were available, and adalimumab was discontinued in six of the eight patients. Of two patients continued on adalimumab, one maintained detectable serum adalimumab despite AAA and one had a low AAA titer.

CONCLUSIONS

For patients receiving adalimumab for ocular inflammatory disease, a disease flare in the setting of previously well-controlled disease should prompt consideration of AAA testing.

Bilateral multifocal choroiditis with disc edema in a 15-year-old girl following COVID-19 vaccination

A few cases of posterior uveitis following COVID-19 vaccination have been reported but none in the pediatric age group. A 15-year-old girl presented with history of headache and bilateral blurred vision of five days duration. The symptoms developed five days after vaccination with the first dose of Covaxin (inactivated SARS-CoV-2 vaccine). Her anterior segment was normal in both eyes (BE), whereas the posterior segment showed mild vitritis with disc edema and multiple yellowish lesions at the level of choroid clustered at the macula and associated with multiple serous detachments. BE uveitis resolved, and the vision was completely recovered three weeks after treatment with steroids. Hence, ophthalmologists should be aware of uveitis following vaccination-a condition that is usually benign, transient, and results in excellent outcomes with timely diagnosis and early treatment with steroids.

JAK-STAT Signaling Pathway in Non-Infectious Uveitis

Non-infectious uveitis (NIU) refers to various intraocular inflammatory disorders responsible for severe visual loss. Cytokines participate in the regulation of ocular homeostasis and NIU pathological processes. Cytokine receptors transmit signals by activating Janus kinase (JAK) and signal transducer and activator of transcription (STAT) proteins. Increasing evidence from human NIU and experimental models reveals the involvement of the JAK-STAT signaling pathway in NIU pathogenesis. Several small-molecule drugs that potentially inhibit multiple cytokine-dependent pathways are under investigation for treating autoimmune diseases, implicating possible applications for NIU treatment. This review summarizes the current understanding of the diverse roles of the JAK-STAT signaling pathway in ocular homeostasis and NIU pathology, providing a rationale for targeting JAKs and STATs for NIU treatment. Moreover, available evidence for the safety and efficacy of JAK inhibitors for refractory uveitis and potential approaches for treatment optimization are discussed.

Topical Ocular Anti-TNFα Agent Licaminlimab in the Treatment of Acute Anterior Uveitis: A Randomized Phase II Pilot Study

Purpose

Licaminlimab is a new anti-TNFα antibody fragment for topical ocular application. This phase II study assessed the tolerability, treatment effect, and pharmacokinetics of licaminlimab in acute anterior uveitis (AAU).

Methods

In this multicenter, randomized, parallel-group, double-masked study, 43 adult patients with non-infectious AAU and Standardization of Uveitis Nomenclature (SUN) anterior chamber (AC) cell score of 2+ or 3+ were randomized (3:1 ratio) to licaminlimab (60 mg/mL, 8 drops/day for 15 days, 4 drops/day for 7 days, then matching vehicle for 7 days) or dexamethasone eye drops (8 drops/day for 15 days, tapering to 1 drop/day over 14 days). The primary efficacy end point was clinical response (≥2-step decrease in AC cell grade at day 15). A treatment effect was considered as established if the lower limit of the 95% posterior interval of the responder rate was >30%. Serum levels of licaminlimab were determined.

Results

The day 15 response rate for licaminlimab was 56%; the lower bound of the 95% credible interval was 40% (i.e. >30%), demonstrating a treatment effect according to prespecified criteria. By day 4, 36% of licaminlimab-treated patients were responders; 76% had an AC cell grade of 0 on ≥1 post-treatment visit. The day 15 dexamethasone response rate was 90% (no inferential between-arm comparison was planned). Both treatments were well-tolerated. Intraocular pressure increased from baseline with dexamethasone but not licaminlimab. Licaminlimab was undetectable in serum in most patients.

Conclusions

Licaminlimab is the first biologic demonstrated to have a treatment effect on an intraocular condition with topical ocular application. The trial met its primary objective and the observed responder rate for licaminlimab was 56.0%. Ocular administration of licaminlimab was well-tolerated in adult subjects with AAU for up to 35 days.

Therapeutic Validation of GEF-H1 Using a De Novo Designed Inhibitor in Models of Retinal Disease

Inflammation and fibrosis are important components of diseases that contribute to the malfunction of epithelia and endothelia. The Rho guanine nucleotide exchange factor (GEF) GEF-H1/ARHGEF-2 is induced in disease and stimulates inflammatory and fibrotic processes, cell migration, and metastasis. Here, we have generated peptide inhibitors to block the function of GEF-H1. Inhibitors were designed using a structural in silico approach or by isolating an inhibitory sequence from the autoregulatory C-terminal domain. Candidate inhibitors were tested for their ability to block RhoA/GEF-H1 binding in vitro, and their potency and specificity in cell-based assays. Successful inhibitors were then evaluated in models of TGFβ-induced fibrosis, LPS-stimulated endothelial cell-cell junction disruption, and cell migration. Finally, the most potent inhibitor was successfully tested in an experimental retinal disease mouse model, in which it inhibited blood vessel leakage and ameliorated retinal inflammation when treatment was initiated after disease diagnosis. Thus, an antagonist that blocks GEF-H1 signaling effectively inhibits disease features in in vitro and in vivo disease models, demonstrating that GEF-H1 is an effective therapeutic target and establishing a new therapeutic approach.

Characterization and Validation of In Vitro and In Vivo Models to Investigate TNF-α-Induced Inflammation in Retinal Diseases

Purpose

Inflammation is implicated in the etiology of diverse retinopathies including uveitis, age-related macular degeneration or diabetic retinopathy. Tumor necrosis factor alpha (TNF-α) is a well-known proinflammatory cytokine that is described as a biomarker for inflammation in diverse retinopathies and therefore emerged as an interesting target to treat inflammation in the eye by neutralizing anti-TNF-α antibodies.

Methods

Recently, we have demonstrated that Adeno-associated virus (AAV)–mediated expression of human TNF-α in the murine eye induces retinal inflammation including vasculitis and fibrosis, thereby mimicking human disease-relevant pathologies. In a proof-of-mechanism study, we now tested whether AAV-TNF-α induced pathologies can be reversed by neutralizing TNF-α antibody treatment.

Results

Strikingly, a single intravitreal injection of the TNF-α antibody golimumab reduced AAV-TNF-α–induced retinal inflammation and retinal thickening. Furthermore, AAV-TNF-α–mediated impaired retinal function was partially rescued by golimumab as revealed by electroretinography recordings. Finally, to study TNF-α-induced vasculitis in human in vitro cell culture assays, we established a monocyte-to-endothelium adhesion co-culture system. Indeed, also in vitro TNF-α induced monocyte adhesion to human retinal endothelial cells, which was prevented by golimumab.

Conclusions

Overall, our study describes valuable in vitro and in vivo approaches to study the function of TNF-α in retinal inflammation and demonstrated a preclinical proof-of-mechanism treatment with golimumab.

Translational Relevance

The AAV-based model expressing human TNF-α allows us to investigate TNF-α–driven pathologies supporting research in mechanisms of retinal inflammation.

Blood-retina barrier dysfunction in experimental autoimmune uveitis: the pathogenesis and therapeutic targets

Experimental autoimmune uveitis (EAU), an animal model of human uveitis, is characterized by infiltration of autoimmune T cells in the uvea as well as in the retina of susceptible animals. EAU is induced by the immunization of uveitogenic antigens, including either retinal soluble-antigen or interphotoreceptor retinoid-binding proteins, in Lewis rats. The pathogenesis of EAU in rats involves the proliferation of autoimmune T cells in peripheral lymphoid tissues and breakdown of the blood-retinal barrier, primarily in the uvea and retina, finally inducing visual dysfunction. In this review, we describe recent EAU studies to facilitate the design of a therapeutic strategy through the interruption of uveitogenic factors during the course of EAU, which will be helpful for controlling human uveitis.

Low Expression of YTH Domain-Containing 1 Promotes Microglial M1 Polarization by Reducing the Stability of Sirtuin 1 mRNA

The N6-methyladenosine (m6A) modification is the most abundant posttranscriptional mRNA modification in mammalian cells and is dynamically modulated by a series of "writers," "erasers," and "readers." Studies have shown that m6A affects RNA metabolism in terms of RNA processing, nuclear export, translation, and decay. However, the role of the m6A modification in retinal microglial activation remains unclear. Here, we analyzed the single-cell RNA sequencing data of retinal cells from mice with uveitis and found that the m6A-binding protein YTH domain-containing 1 (YTHDC1) was significantly downregulated in retinal microglia in the context of uveitis. Further studies showed that YTHDC1 deficiency resulted in M1 microglial polarization, an increased inflammatory response and the promotion of microglial migration. Mechanistically, YTHDC1 maintained sirtuin 1 (SIRT1) mRNA stability, which reduced signal transducer and activator of transcription 3 (STAT3) phosphorylation, thus inhibiting microglial M1 polarization. Collectively, our data show that YTHDC1 is critical for microglial inflammatory response regulation and can serve as a target for the development of therapeutics for autogenic immune diseases.

Beneficial effect of dimethyl fumarate on experimental autoimmune uveitis is dependent of pro-inflammatory markers immunomodulation

Autoimmune uveitis is an inflammatory disease of the eye and is one of the major causes of blindness worldwide. Experimental autoimmune uveoretinitis (EAU) constitutes an animal disease model of human endogenous uveitis. In our study, we investigated the immunomodulatory effect of dimethyl fumarate (DMF) using bovine retinal extract-induced uveitis in a Female Wistar rats. To evaluate the in vivo efficacy, Female Wistar rats were divided into seven experimental groups: control group (n = 5), consisting of non-immunized animals; Uveoretinitis (n = 5), and DMF/Uveoretinitis groups (n = 15), which received a subcutaneous injection of bovine retinal extract emulsified in complete Freund's adjuvant; MC group (n = 5), treated by daily intragastric administration of methylcellulose 0.08% in tap water; DMF group, consisting of control positive group, rats received daily oral gavage administration of 500 μL of dimethyl fumarate at 100 mg/Kg dissolved in 0.08% methylcellulose in tap water (n = 5). On day 14 post immunization, the rats were then euthanized and associated indications were investigated to evaluate the therapeutic efficacy. Nitric oxide (NO) and TNF-α were assessed in plasma. Meanwhile, eyes were collected for histological and immunohistochemical studies. The retinal expression of iNOS, CD68, CD20, CD25, CD4, and CD8 was examined. Interestingly, DMF enhanced a significant reduction of NO and TNF-α production in the treated group. This effect was strongly related to the histological structure of eyes improvement. In the same context, a significant decrease of iNOS, CD68, and CD20 expression and CD25 increase expression were reported in retinal tissue of DMF/Uveoretinitis group in comparison to the immunized group. Collectively, our results indicate that DMF treatment has a beneficial effect in experimental autoimmune uveoretinitis and could constitute a good candidate for monitoring an ocular inflammatory diseases.

Prednisone Reprograms the Transcriptional Immune Cell Landscape in CNS Autoimmune Disease

Glucocorticoids (GCs) are widely used immunosuppressive drugs for autoimmune diseases, although considerable gaps exist between current knowledge of the mechanisms of GCs and their conclusive immune-regulatory effects. Here we generated a single-cell transcriptional immune cell atlas based on prednisone-treated or untreated experimental autoimmune uveitis (EAU) mice. Immune cells were globally activated in EAU, and prednisone partially reversed this effect in terms of cell composition, gene expression, transcription factor regulation, and cell-cell communication. Prednisone exerted considerable rescue effects on T and B cells and increased the proportion of neutrophils. Besides commonly regulated transcriptional factors (Fosb, Jun, Jund), several genes were only regulated in certain cell types (e.g. Cxcr4 and Bhlhe40 in T cells), suggesting cell-type-dependent immunosuppressive properties of GC. These findings provide new insights into the mechanisms behind the properties and cell-specific effects of GCs and can potentially benefit immunoregulatory therapy development.

Perspectives for immunotherapy in noninfectious immune mediated uveitis

Introduction: Noninfectious uveitis (NIU) is one of the leading causes of blindness worldwide. In adult patients, anterior NIU is usually managed with topical corticosteroids. In intermediate, posterior uveitis. and panuveitis, systemic corticosteroids are used especially in case of bilaterality or association with systemic disease. Biotherapies are recommended in case of inefficacy or intolerance to corticosteroids or conventional immunosuppressive drugs. Anti-TNF-α agents are by far the most widely used biotherapies. In case of failure or poor tolerance to anti-TNF-α, new targeted therapies can be proposed.Areas covered: We present and discuss an updated overview on biologics and biotherapies in NIU.Expert opinion: In case of dependency to systemic or intravitreal steroids, sight-threatening disease, and/or failure of conventional immunosuppressive drugs, anti-TNF-α are used as first-line biologics to achieve quiescence of inflammation. Anti-interleukin-6 is another option that may be proposed as first-line biologic or in case of poor efficacy of anti-TNF-α. Interferon can be directly proposed in specific indications (e.g. refractory macular edema, sight-threatening Behçet's uveitis). In the rare cases that remain unresponsive to traditional biotherapies, novel molecules, such as Janus-associated-kinase and anti-phosphodiesterase-4-inhibitors can be used. Therapeutic response must always be evaluated by clinical and appropriate ancillary investigations.

Update on biologic therapies for juvenile idiopathic arthritis-associated uveitis

Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease of childhood, and juvenile idiopathic associated uveitis (JIA-U) is the most frequently noted extra-articular manifestation. JIA-U can present asymptomatically and lead to ocular complications, so regular screening and monitoring are needed to prevent potentially sight-threatening sequelae. Topical glucocorticoids such as prednisolone acetate are usually the first line of treatment for anterior uveitis associated with JIA-U, but long-term use may be associated with cataract, ocular hypertension and glaucoma. Disease modifying anti-rheumatic drugs (DMARDs) such as methotrexate allow tapering of the corticosteroids to prevent long-term complications. Biologic therapies have been increasingly used as targeted therapies for JIA-U, particularly monoclonal antibodies targeting the proinflammatory cytokine TNF-α such as adalimumab and infliximab. One recent, multicenter, prospective, randomized clinical trial provided evidence of the efficacy of adalimumab with methotrexate for JIA-U compared to methotrexate alone. Another clinical trial studying the interleukin-6 inhibitor tocilizumab for JIA-U showed promise in tapering topical corticosteroids. Additionally, JAK inhibitors are emerging biologic therapies for JIA-U in patients refractory to TNF-α inhibitors, with a clinical trial assessing the efficacy of baricitinib for JIA-U underway. While clinical trials on these novel biologics are limited, further investigation of these agents may provide additional therapeutic options for JIA-U.

A Review of the Various Roles and Participation Levels of B-Cells in Non-Infectious Uveitis

Non-infectious uveitis is an inflammatory disorder of the eye that accounts for severe visual loss without evident infectious agents. While T cells are supposed to dominate the induction of inflammation in non-infectious uveitis, the role of B cells in the pathogenesis of this disease is obscure. Therefore, this review aimed to discuss diverse B-cell participation in different non-infectious uveitides and their roles in the pathogenesis of this disease as well as the mechanism of action of rituximab. Increasing evidence from experimental models and human non-infectious uveitis has suggested the participation of B cells in non-infectious uveitis. The participation levels vary in different uveitides. Furthermore, B cells play multiple roles in the pathogenic mechanisms. B cells produce autoantibodies, regulate T cell responses via antibody-independent functions, and constitute ectopic lymphoid structures. Regulatory B cells perform pivotal anti-inflammatory functions in non-infectious uveitis. Rituximab may work by depleting pro-inflammatory B cells and restoring the quantity and function of regulatory B cells in this disease. Identifying the levels of B-cell participation and the associated roles is beneficial for optimizing therapy. Diversified experimental model choices and emerging tools and/or methods are conducive for future studies on this topic.

A Non-Infectious Uveitis Multidisciplinary Clinic in a Tertiary Referral Center: Clinical Impact and Added Value

Non-infectious uveitis (NIU) is a group of sight-threatening diseases that generates significant burden for the healthcare systems due to its adverse outcomes, irreversible structural complications in the eye with loss of visual function, limited clinical expertise and low-grade evidence for best practice. The usefulness of multidisciplinary care, specifically close collaboration between Rheumatologists and Ophthalmologists in NIU, has been emphasized in the literature. In this paper, the assessment tools and protocols used in our clinic are depicted and an overview of our activity with a brief description of the patients included in our registry, between 2018 and 2020 is provided. The cohort of 290 patients assessed in our NIU clinic, their demographics, sources of referral, details about immunosuppression treatment, and internal and external collaborations is described. This experience-based manuscript aims to describe the general functioning of our multidisciplinary NIU clinic, highlighting the benefits and drawbacks of multidisciplinary team management in patients with NIU, ultimately initiating a dialogue on what an NIU clinic should be and providing information for newly NIU clinics start-up. In conclusion, establishing a standardized and multidisciplinary clinic in NIU allows to systematically observe and follow-up this infrequent disease at a tertiary hospital level, thus improving quality of care delivery and research avenues.

Efficacy and Safety of Adalimumab Therapy for the Treatment of Non-infectious Uveitis: Efficacy comparison among Uveitis Aetiologies

Objective: To assess the efficacy and safety of adalimumab treatment in patients with Non-infectious uveitis.Methods: This was a single-center retrospective chart review of patients with active Non-infectious uveitis who had received adalimumab in Japan. Outcome variables included change in systemic immunosuppressive treatment, intraocular inflammation, visual acuity, and relapse rate.Results: In total, 48 patients were included. After the initiation of adalimumab, more than 80% of the patients received systemic corticosteroid ≤5 mg from 3 months onwards. Intraocular inflammation, relapse rate, and visual acuity showed persistent improvement. Adalimumab and methotrexate combination therapy was required in 71.4% of the patients with Vogt-Koyanagi-Harada disease/sympathetic ophthalmia, whereas it was required in only 18.0% of the patients with Behçet's disease. There were no serious side effects that required discontinuation of adalimumab.Conclusion: Adalimumab is efficacious and safe for the treatment of patients with Non-infectious uveitis. Differences in the efficacy of adalimumab treatment may exist between patients with Vogt-Koyanagi-Harada disease/sympathetic ophthalmia and patients with Behçet's disease.

Regulated Tristetraprolin Overexpression Dampens the Development and Pathogenesis of Experimental Autoimmune Uveitis

Non-infectious uveitis, a common cause of blindness in man, is often mediated by autoimmunity, a process in which cytokines play major roles. The biosynthesis and secretion of pro-inflammatory cytokines are regulated in part by tristetraprolin (TTP), an endogenous anti-inflammatory protein that acts by binding directly to specific sequence motifs in the 3'-untranslated regions of target mRNAs, promoting their turnover, and inhibiting synthesis of their encoded proteins. We recently developed a TTP-overexpressing mouse (TTPΔARE) by deleting an AU-rich element (ARE) instability motif from the TTP mRNA, resulting in increased accumulation of TTP mRNA and protein throughout the animal. Here, we show that homozygous TTPΔARE mice are resistant to the induction of experimental autoimmune uveitis (EAU) induced by interphotoreceptor retinoid-binding protein (IRBP), an established model for human autoimmune (noninfectious) uveitis. Lymphocytes from TTPΔARE mice produced lower levels of the pro-inflammatory cytokines IFN-γ, IL-17, IL-6, and TNFα than wild type (WT) mice. TTPΔARE mice also produced lower titers of antibodies against the uveitogenic protein. In contrast, TTPΔARE mice produced higher levels of the anti-inflammatory cytokine IL-10, and had higher frequencies of regulatory T-cells, which, moreover, displayed a moderately higher per-cell regulatory ability. Heterozygous mice developed EAU and associated immunological responses at levels intermediate between homozygous TTPΔARE mice and WT controls. TTPΔARE mice were able, however, to develop EAU following adoptive transfer of activated WT T-cells specific to IRBP peptide 651-670, and naïve T-cells from TTPΔARE mice could be activated by antibodies to CD3/CD28. Importantly, TTPΔARE antigen presenting cells were significantly less efficient compared to WT in priming naïve T cells, suggesting that this feature plays a major role in the dampened immune responses of the TTPΔARE mice. Our observations demonstrate that elevated systemic levels of TTP can inhibit the pathogenic processes involved in EAU, and suggest the possible use of TTP-based treatments in humans with uveitis and other autoimmune conditions.

[Immunosuppressive therapy in severe or chronic pediatric uveitis: Review of the literature]

Immunosuppressants are prescribed for pediatric uveitis in cases of severe involvement affecting the prognosis for vision or life, in cases of recurrent or chronic uveitis to achieve corticosteroid sparing, or in cases of corticosteroid resistance. Immunosuppressants used in children include antimetabolites (methotrexate, mycophenolate mofetil, azathioprine), cyclosporine, tacrolimus, and biologics, including infliximab, adalimumab, anakinra, canakinumab, and tocilizumab. The mechanisms of action and indications of the various immunosuppressants are described in this review.

Recent Developments in HLA B27 Anterior Uveitis

There has been steady progress in understanding the pathogenesis, clinical features, and effective treatment of acute anterior uveitis (AU) over the past 5 years. Large gene wide association studies have confirmed that AU is a polygenic disease, with overlaps with the seronegative arthropathies and inflammatory bowel diseases, associations that have been repeatedly confirmed in clinical studies. The role of the microbiome in AU has received increased research attention, with recent evidence indicating that human leukocyte antigen B27 (HLA B27) may influence the composition of the gut microbiome in experimental animals. Extensive clinical investigations have confirmed the typical features of acute AU (AAU) and its response to topical, regional and systemic immunosuppressive treatment. Increased understanding of the role of cytokines has resulted in studies confirming the value of anti-cytokine therapy [anti-tumor necrosis factor (anti-TNF) and interleukin 6 (IL-6) therapy] in severe and recurrent cases of AAU, particularly in subjects with an associated spondyloarthopathy (SpA) and in juvenile idiopathic arthritis (JIA)-associated AAU.

Paediatric autoimmune and autoinflammatory conditions associated with uveitis

Childhood uveitis comprises a collection of heterogenous ocular phenotypes which are associated with a diverse range of childhood autoimmune and autoinflammatory disorders. Of these genetic and/or acquired disorders, juvenile idiopathic arthritis is the most common, affecting 30-80% of children with uveitis. Up to a third of children with uveitis have 'isolated' idiopathic disease and do not have an associated systemic disease which manifests in childhood. However, uveitis may be the presenting manifestation of disease; thus, the apparently well child who presents with uveitis may have isolated idiopathic disease, but they may have an evolving systemic disorder. The diagnosis of most of the associated disorders is reliant on clinical features rather than serological or genetic investigations, necessitating detailed medical history taking and systemic examination. Adequate control of inflammation is key to good visual outcomes, and multidisciplinary care is key to good broader health outcomes.

[Anti-TNF-α in the treatment of non-infectious uveitis]

Non-infectious uveitis is a heterogenous group of potentially blinding ocular autoimmune diseases that may represent a manifestation of a systemic condition or may affect the eyes only. A systemically administered anti-TNF has recently been approved for the treatment of non-infectious uveitis, broadening the therapeutic arsenal available to control intraocular inflammation and reduce uveitis complications that can lead to vision loss. When uveitis affects only the eyes, a local anti-TNF-α administration strategy could optimize the ocular therapeutic effect and reduce undesirable systemic side-effects. A new ocular method of non-viral gene therapy, currently in development, may broaden the indications for ocular anti-TNF-α agents, not only for uveitis but also for other diseases in which TNF-α-mediated neuro-inflammation has been demonstrated.

Adalimumab in combination with methotrexate for refractory uveitis associated with juvenile idiopathic arthritis: a RCT

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) are at risk of uveitis. The role of adalimumab (Humira^®; AbbVie Inc., Ludwigshafen, Germany) in the management of uveitis in children needs to be determined.

OBJECTIVE

To compare the efficacy, safety and cost-effectiveness of adalimumab in combination with methotrexate (MTX) versus placebo with MTX alone, with regard to controlling disease activity in refractory uveitis associated with JIA.

DESIGN

This was a randomised (applying a ratio of 2 : 1 in favour of adalimumab), double-blind, placebo-controlled, multicentre parallel-group trial with an integrated economic evaluation. A central web-based system used computer-generated tables to allocate treatments. A cost-utility analysis based on visual acuity was conducted and a 10-year extrapolation by Markov modelling was also carried out.

SETTING

The setting was tertiary care centres throughout the UK.

PARTICIPANTS

Patients aged 2-18 years inclusive, with persistently active JIA-associated uveitis (despite optimised MTX treatment for at least 12 weeks).

INTERVENTIONS

All participants received a stable dose of MTX and either adalimumab (20 mg/0.8 ml for patients weighing < 30 kg or 40 mg/0.8 ml for patients weighing ≥ 30 kg by subcutaneous injection every 2 weeks based on body weight) or a placebo (0.8 ml as appropriate according to body weight by subcutaneous injection every 2 weeks) for up to 18 months. A follow-up appointment was arranged at 6 months.

MAIN OUTCOME MEASURES

Primary outcome - time to treatment failure [multicomponent score as defined by set criteria based on the Standardisation of Uveitis Nomenclature (SUN) criteria]. Economic outcome - incremental cost per quality-adjusted life-year (QALY) gained from the perspective of the NHS in England and Personal Social Services providers. Full details of secondary outcomes are provided in the study protocol.

RESULTS

A total of 90 participants were randomised (adalimumab, n = 60; placebo, n = 30). There were 14 (23%) treatment failures in the adalimumab group and 17 (57%) in the placebo group. The analysis of the data from the double-blind phase of the trial showed that the hazard risk (HR) of treatment failure was significantly reduced, by 75%, for participants in the adalimumab group (HR 0.25, 95% confidence interval 0.12 to 0.51; p < 0.0001 from log-rank test). The cost-effectiveness of adalimumab plus MTX was £129,025 per QALY gained. Adalimumab-treated participants had a much higher incidence of adverse and serious adverse events.

CONCLUSIONS

Adalimumab in combination with MTX is safe and effective in the management of JIA-associated uveitis. However, the likelihood of cost-effectiveness is < 1% at the £30,000-per-QALY threshold.

FUTURE WORK

A clinical trial is required to define the most effective time to stop therapy. Prognostic biomarkers of early and complete response should also be identified.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN10065623 and European Clinical Trials Database number 2010-021141-41.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 15. See the NIHR Journals Library website for further project information. This trial was also funded by Arthritis Research UK (grant reference number 19612). Two strengths of adalimumab (20 mg/0.8 ml and 40 mg/0.8 ml) and a matching placebo were manufactured by AbbVie Inc. (the Marketing Authorisation holder) and supplied in bulk to the contracted distributor (Sharp Clinical Services, Crickhowell, UK) for distribution to trial centres.

Interaction of inflammatorily activated retinal pigment epithelium with retinal microglia and neuronal cells

In age-related macular degeneration, inflammatory events are presumed to contribute to disease development. A primary suspect of this contribution is the microglia, the innate immune cell of the retina. In addition, retinal pigment epithelium (RPE) cells can be inflammatorily activated. In this study, we investigate the effect of activated RPE cells on retinal microglia and on neuronal cells. RPE cells and microglia were harvested from porcine eyes. In addition, a neuronal cell line (SHSY-5Y) of human origin was used. For inflammatory activation, agonists of toll-like receptors in different concentrations were used: Pam2CSK4 (Pam; TLR-2), Polyinosinic:polycytidylic acid (Poly I:C; TLR-3) and lipopolysaccharid (LPS; TLR-4). Cell viability was investigated with an MTT assay. The secretion of cytokines was assessed in an ELISA and their expression in real-time PCR. There was no effect of the agonists on cell viability in RPE cells. All agonists induced the secretion of IL-6 and IL-8 in RPE cells with the strongest effect induced by LPS. In microglia, pro-inflammatory stimulation increased the metabolic activity. All agonists induced the secretion of IL-1ß, IL-8, and TNFα in microglia cells while in real-time PCR, LPS and Pam induced the expression of IL-6, IL-1ß and iNOS. Direct stimulation of SHSY-5Y with the agonists induced only minor alterations of viability. Stimulated RPE cell supernatant reduced the secretion of TNFα and IL-8 irrespective of the inducing agent in microglia cells. Additionally a slight induction of IL-1ß was found in microglia treated with supernatant of RPE cells treated with Pam. In real time PCR, the supernatant of RPE cells stimulated with LPS significantly reduced the expression of iNOS and IL-6, but not of IL-1ß. Of note, the expression of iNOS was also reduced by naive RPE cells. The treatment of the SHSY-5Y with supernatant of microglia previously treated with RPE conditioned medium significantly decreased SHSY-5Y viability with and without pro-inflammatory treatment. In conclusion, inflammatory activated RPE cells have a regulatory effect on the pro-inflammatory activation of microglia, stressing the importance of the interaction between these two retinal cell types. Microglia treated with RPE supernatant reduced viability of a neuronal cell line, indicating a neurotoxic effect.

Ocular manifestations of inflammatory bowel diseases: an update for gastroenterologists

Inflammatory bowel diseases (IBD), that includes ulcerative colitis and Crohn's disease, can affect not only the gastrointestinal tract but a wide spectrum of organs. The extra-intestinal manifestations (EIMs) are one of the most challenging aspect of IBD, playing a significant role for the lifetime care and the quality of life of patients. Ocular manifestations are the third most frequent EIMs, preceded by articular and dermatological ones. The aim of this narrative review is to describe the different types of ocular involvements, focusing on their clinical management. Uveitis and episcleritis are the most common ocular EIMs, differing for many aspects. Uveitis are unrelated with IBD activity and they even precede the onset of the intestinal disease, while episcleritis are common defined as a good mark of IBD activity. Pain is uncommon in most cases of episcleritis, while severe eye pain and photophobia are the most frequent onset of anterior uveitis. Less common but even more severe, are orbital pseudotumor or posterior segment involvement. Most of the ocular EIMs can be successfully treated with topic and oral steroids and the underlying therapy for IBD can reduce or cut out at all the recurrence of these manifestations. Symptoms are commonly not specific, in some cases being unnoticed for years leading to permanent ocular consequences. Cooperation between different specialists is crucial to avoid all the possible consequences of a non-treated EIMs, especially for ocular ones.

Current standardized therapeutic approach for uveitis in Japan

Uveitis is an ocular disease associated with systemic immune-mediated diseases such as rheumatoid arthritis, inflammatory bowel disease and ankylosing spondylitis; and infectious diseases. Infectious uveitis occasionally shows symptoms similar to those of non-infectious uveitis. Therefore, distinguishing between non-infectious and infectious uveitis is critical for definitive diagnosis and appropriate choice of treatment. Once the cause of infection is known, treatment can be promptly initiated. However, in contrast to infectious uveitis, non-infectious uveitis is more difficult to diagnose clinically. Eliminating the possibility of infectious uveitis is important because unlike the infectious type, non-infectious uveitis is treated with immunosuppressive drugs such as corticosteroids and biological agents. Compared to other countries, the drugs available in Japan are limited. Cyclosporin A is the only immunosuppressive drug available for treating uveitis in Japan, and infliximab and adalimumab are the only biological drugs that have been approved for use in the treatment of uveitis in Japan. In this review, I describe the characteristics of typical non-infectious uveitis in Japan and its treatment methods.

The effectiveness of adalimumab treatment for non-infectious uveitis

Uveitis, which is a major cause of blindness worldwide, is defined as intraocular inflammation that affects the iris, ciliary body, vitreous, retina and choroid. Tumor necrosis factor-alpha (TNF-α) is a key cytokine involved in the pathogenesis of many inflammatory diseases including uveitis. Corticosteroids and immunosuppressive agents are the conventional therapy to treat non-infectious uveitis. In cases that are resistant to these therapies, anti-TNF agents are added. An anti-TNF-α agent, adalimumab, was recently approved for the treatment of refractory non-infectious uveitis. In this review, we provide an introduction to uveitis and summarize the effectiveness and safety of adalimumab in the treatment of non-infectious uveitis.

Targets of immunomodulation in bacterial endophthalmitis

Bacterial infection of the posterior segment of the eye (endophthalmitis) leads to a robust host response that often results in irreversible damage to the layers of the retina, significant vision loss, and in some patients, enucleation of the globe. While a great deal of effort has gone into understanding the role of bacterial virulence factors in disease initiation and propagation, it is becoming increasingly clear that the host response to infection plays a major role in causing the damage associated with endophthalmitis. Researchers have identified the host receptors which detect infecting organisms and initiate the cascade of events that result in inflammation. This inflammation may damage nonregenerative tissues of the eye while attempting to clear the infection. Both Gram-positive and Gram-negative bacteria can cause endophthalmitis. These organisms initiate an immune response by activating toll-like receptor (TLR) pathways. Once an inflammatory response is initiated, the expression of immunomodulators, such as proinflammatory chemokines and cytokines, affect the recruitment of PMNs and other inflammatory cells into the eye. We and others have reported that knockout mice that do not express specific inflammatory pathways and molecules have an attenuated response to infection and retain significant retinal function. These findings suggest that host immune mediators are important components of the response to infections in the posterior segment of the eye, and the timing and level of their production may be related to the severity of the damage and the ultimate visual outcome. If that is the case, a better understanding of the complex and often redundant role of these pathways and inflammatory mediators may identify host molecules as potential anti-inflammatory therapeutic targets. This review highlights potential anti-inflammatory targets during acute inflammation in endophthalmitis, compares and contrasts those with findings in other models of ocular inflammation, and translates current immunomodulatory strategies for other types of infection and inflammation to this blinding disease. Given the poor visual outcomes seen in patients treated with antibiotics alone or in combination with corticosteroids, immunomodulation in addition to antibiotic therapy might be more effective in preserving vision than current regimens.

Update in treatment of uveitic macular edema

Macular edema (ME) represents the most common cause for visual loss among uveitis patients. The management of uveitic macular edema (UME) may be challenging, due to its often recalcitrant nature. Corticosteroids remain the mainstay of treatment, through their capability of effectively controlling inflammation and the associated ME. Topical steroids may be effective in milder cases of UME, particularly in edema associated with anterior uveitis. Posterior sub-Tenon and orbital floor steroids, as well as intravitreal steroids often induce rapid regression of UME, although this may be followed by recurrence of the pathology. Intra-vitreal corticosteroid implants provide sustained release of steroids facilitating regression of ME with less frequent injections. Topical nonsteroidal anti-inflammatory drugs may provide a safe alternative or adjuvant therapy to topical steroids in mild UME, predominantly in cases with underlying anterior uveitis. Immunomodulators including methotrexate, mycophenolate mofetil, tacrolimus, azathioprine, and cyclosporine, as well as biologic agents, notably the anti-tumor necrosis factor-α monoclonal antibodies adalimumab and infliximab, may accomplish the control of inflammation and associated ME in refractory cases, or enable the tapering of steroids. Newer biotherapies have demonstrated promising outcomes and may be considered in persisting cases of UME.

Miliary tuberculosis developing during adalimumab treatment for Behçet's disease with uveitis

Tumour necrosis factor-alpha (TNF-α) is a key proinflammatory cytokine in non-infective uveitis (NIU). Adalimumab, an anti-TNF-α monoclonal antibody, is approved for the treatment of severe NIU by the European Medicines Agency. There is a recognised risk of serious infections, including tuberculosis (TB), during anti-TNF-α therapy in systemic immune-mediated diseases. We describe miliary pulmonary TB during adalimumab therapy for severe NIU. To our knowledge, this is the first detailed report of this complication in a patient with uveitis. We present the challenges of managing vision-threatening uveitis during life-threatening infection necessitating withdrawal of adalimumab and oral immunosuppression therapy. Uveitis activity was controlled during anti-TB therapy with oral corticosteroid therapy.

The Management of Acute Anterior Uveitis Complicating Spondyloarthritis: Present and Future

Spondyloarthropathies (SpA) encompass a group of chronic inflammatory diseases sharing common genetic and clinical features, including the association with HLA-B27 antigen, the involvement of both the axial and the peripheral skeleton, the presence of dactylitis, enthesitis, and typical extra-articular manifestations such as psoriasis, inflammatory bowel disease, and acute anterior uveitis (AAU). The latter is commonly reported as a noninfectious acute inflammation of the anterior uveal tract and its adjacent structures. AAU may affect more than 20% of SpA patients representing the most common extra-articular manifestation of the disease. Considering the potential consequences of untreated AAU, early diagnosis and aggressive treatment are crucial to avoid complications of remittent or chronic eye inflammation, such as visual loss and blindness. The management of SpA has dramatically improved over the last decades due to the development of new treat-to-target strategies and to the introduction of biologic disease modifying antirheumatic drugs (bDMARDs), particularly tumor necrosis factor alpha inhibitors (TNFis), currently used for the treatment of nonresponder patients to conventional synthetic agents. Along with the improvement of musculoskeletal features of SpA, bDMARDs provided an additional effect also in the management of AAU in those patients who are failures to topical and systemic conventional therapies. Nowadays, five TNFis, one interleukin-17, and one interleukin 12/23 blocker are licensed for the treatment of SpA, with different proven efficacy in preventing and treating ocular involvement. The aim of this review is to summarize the current options and to analyze the future perspectives for the management of SpA-associated AAU.

Efficacy and safety of intravitreal anti-tumour necrosis factor drugs in adults with non-infectious uveitis - a systematic review

Anti-tumour necrosis factor (TNF) drugs have been extensively used in non-infectious uveitis (NIU), when corticosteroids or conventional immunosuppressive drugs cannot adequately control inflammation or intolerable side-effects occur. However, systemic anti-TNF therapies are also associated with a myriad of side-effects. Therefore, intravitreal administration of anti-TNF biologics has been employed to minimize patient morbidity and systemic adverse effects, while maintaining therapeutic effectivity. We undertook a systematic review to determine evidence of efficacy and safety of intravitreal administration of anti-TNF drugs in adults with NIU. We conducted this systematic review according to the PRISMA guidelines. The protocol was registered with PROSPERO (CRD42016041946). We searched CENTRAL, MEDLINE and EMBASE, from inception to April 2017, as well as clinical trial registries and grey literature. The qualitative analysis included all studies of adult patients with a diagnosis of NIU and who received intravitreal anti-TNF drugs with a 4-week minimum follow-up. A total of 4840 references were considered for title and abstract screening. Seven full texts were screened, and five studies were considered for analysis. All studies were open-label, single-centre, prospective, non-randomized, interventional case series with a follow-up between 4 and 26 weeks, employing either adalimumab in two studies and infliximab in three. Three studies showed a treatment effect of anti-TNF intravitreal injections, while one study revealed short-term improvement and one study revealed no efficacy of anti-TNF intravitreal therapy. None of the studies reported ocular adverse effects but only two studies included electrophysiological assessment in the safety analysis and no study assessed systemic human anti-drug antibodies. The available evidence is not sufficiently robust to conclude about the clinical effectivity of intravitreal anti-TNF in NIU and so no recommendation can be made. In conclusion, intravitreal injection of anti-TNF antibodies remains a possible treatment option to be explored through robust clinical investigation.

Adenosine A1 receptor: A neuroprotective target in light induced retinal degeneration

Light induced retinal degeneration (LIRD) is a useful model that resembles human retinal degenerative diseases. The modulation of adenosine A1 receptor is neuroprotective in different models of retinal injury. The aim of this work was to evaluate the potential neuroprotective effect of the modulation of A1 receptor in LIRD. The eyes of rats intravitreally injected with N6-cyclopentyladenosine (CPA), an A1 agonist, which were later subjected to continuous illumination (CI) for 24 h, showed retinas with a lower number of apoptotic nuclei and a decrease of Glial Fibrillary Acidic Protein (GFAP) immunoreactive area than controls. Lower levels of activated Caspase 3 and GFAP were demonstrated by Western Blot (WB) in treated animals. Also a decrease of iNOS, TNFα and GFAP mRNA was demonstrated by RT-PCR. A decrease of Iba 1⁺/MHC-II⁺ reactive microglial cells was shown by immunohistochemistry. Electroretinograms (ERG) showed higher amplitudes of a-wave, b-wave and oscillatory potentials after CI compared to controls. Conversely, the eyes of rats intravitreally injected with dipropylcyclopentylxanthine (DPCPX), an A1 antagonist, and subjected to CI for 24 h, showed retinas with a higher number of apoptotic nuclei and an increase of GFAP immunoreactive area compared to controls. Also, higher levels of activated Caspase 3 and GFAP were demonstrated by Western Blot. The mRNA levels of iNOS, nNOS and inflammatory cytokines (IL-1β and TNFα) were not modified by DPCPX treatment. An increase of Iba 1⁺/MHC-II⁺ reactive microglial cells was shown by immunohistochemistry. ERG showed that the amplitudes of a-wave, b-wave, and oscillatory potentials after CI were similar to control values. A single pharmacological intervention prior illumination stress was able to swing retinal fate in opposite directions: CPA was neuroprotective, while DPCPX worsened retinal damage. In summary, A1 receptor agonism is a plausible neuroprotective strategy in LIRD.

The expression of C1 inhibitor (C1INH) in macrophages is upregulated by retinal pigment epithelial cells - implication in subretinal immune privilege in the aging eye

Age-related para-inflammation in the retina-choroidal interface is featured by low-levels of complement activation and subretinal macrophage accumulation. This study aimed to understand how complement expression in macrophages is regulated by retinal pigment epithelium (RPE). Bone marrow-derived macrophages (BMDMs) and RPE cells were cultured from 8-10 weeks old C57BL/6J mice. The BMDMs were co-cultured with normal RPE, or oxidized photoreceptor outer segment (oxPOS) or TNF-α pre-treated RPE, or apoptotic RPE, or RPE-choroid eyecups. Macrophages were then isolated and processed for real-time RT-PCR. The expression of complement inhibitor C1INH in BMDMs was significantly upregulated by RPE and RPE-choroid eyecups. The eyecups also upregulated CFH, CD59a, and Crry in BMDMs. oxPOS pre-treated RPE upregulated C1qb but down-regulated C3 expression in BMDMs. TNF-α pre-treated RPE enhanced C1INH and CFB expression. When BMDMs were treated with apoptotic RPE, the expression of C1qb, CFH, and CD59a was reduced, whereas the expression of C3, CFB and C1INH was increased. Our results suggest that RPE can modulate macrophages complement expression at the retina-choroidal interface even under aging or oxidative conditions. However, during inflammation, they may promote the alternative pathway of complement activation through down-regulating CFH and CD59a and upregulating CFB and C3.

Galectin-7 promotes proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting The TGFβ/Smad3 pathway

Galectin-7 (Gal-7) has been associated with cell proliferation and apoptosis. It is known that Gal-7 antagonises TGFβ-mediated effects in hepatocytes by interacting with Smad3. Previously, we have demonstrated that Gal-7 is related to CD4+ T cells responses; nevertheless, its effect and functional mechanism on CD4+ T cells responses remain unclear. The murine CD4+ T cells were respectively cultured with Gal-7, anti-CD3/CD28 mAbs, or with anti-CD3/CD28 mAbs & Gal-7. The effects of Gal-7 on proliferation and the phenotypic changes in CD4+ T cells were assessed by flow cytometry. The cytokines from CD4+ T cells were analysed by quantitative real-time PCR. Subcellular localisation and expression of Smad3 were determined by immunofluorescence staining and Western blot, respectively. Gal-7 enhanced the proliferation of activated CD4+ T cells in a dose- and β-galactoside-dependent manner. Additionally, Gal-7 treatment did not change the ratio of Th2 cells in activated CD4+ T cells, while it increased the ratio of Th1 cells. Gal-7 also induced activated CD4+ T cells to produce a higher level of IFN-γ and TNF-α and a lower level of IL-10. Moreover, Gal-7 treatment significantly accelerated nuclear export of Smad3 in activated CD4+ T cells. These results revealed a novel role of Gal-7 in promoting proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting the TGFβ/Smad3 pathway.

Theissenolactone C Exhibited Ocular Protection of Endotoxin-Induced Uveitis by Attenuating Ocular Inflammatory Responses and Glial Activation

The aim of this study was to investigate the effects of a natural component, theissenolactone C (LC53), on the ocular inflammation of experimental endotoxin-induced uveitis (EIU) and its related mechanisms in microglia. Evaluation of the severity of anterior uveitis indicated that LC53 treatment significantly decreased iridal hyperemia and restored the clinical scores. Additionally, the deficient retina functions of electroretinography were improved by LC53. LC53 significantly reduced levels of tumor necrosis factor (TNF)-α, monocyte chemoattractant protein-1, protein leakage and activation of matrix metalloproteinases in the anterior section during EIU. Moreover, LC53 treatment decreased the oxidative stress as well as neuroinflammatory reactivities of GFAP and Iba-1 in the posterior section. Furthermore, LC53 decreased the phosphorylation of p65, expression of HSP90, Bax, and cleaved-caspase-3 in EIU. According to the microglia studies, LC53 significantly abrogated the productions of TNF-α, PGE₂, NO and ROS, as well as inducible NO synthase and cyclooxygenase-2 expression in LPS-stimulated microglial BV2 cells. The microglial activation of IKKβ, p65 phosphorylation and nuclear phosphorylated p65 translocation were strongly attenuated by LC53. On the other hand, LC53 exhibited the inhibitory effects on JNK and ERK MAPKs activation. Our findings indicated that LC53 exerted the ocular-protective effect through its inhibition on neuroinflammation, glial activation, and apoptosis in EIU, suggesting a therapeutic potential with down-regulation of the NF-κB signaling for uveitis and retinal inflammatory diseases.

Safety and Efficacy of Adalimumab in Patients with Noninfectious Uveitis in an Ongoing Open-Label Study: VISUAL III

PURPOSE

To evaluate safety and efficacy of adalimumab in patients with noninfectious intermediate, posterior, or panuveitis.

DESIGN

Phase 3, open-label, multicenter clinical trial extension (VISUAL III).

PARTICIPANTS

Adults meeting treatment failure (TF) criteria or who completed VISUAL I or II (phase 3, randomized, double-masked, placebo-controlled) without TF.

METHODS

Patients received adalimumab 40 mg every other week. Interim follow-up data were described from VISUAL III weeks 0 through 78.

MAIN OUTCOME MEASURES

Disease quiescence, steroid-free quiescence, active inflammatory chorioretinal/retinal vascular lesions, anterior chamber cell grade, vitreous haze grade, best-corrected visual acuity (BCVA), and corticosteroid dose. Binary data were reported using nonresponder imputation (NRI), continuous data using last observation carried forward and as-observed analysis, and corticosteroid dose using observed-case analysis. Adverse events (AEs) were reported from first adalimumab dose in VISUAL III through interim cutoff.

RESULTS

Of 424 patients enrolled, 371 were included in intent-to-treat analysis. At study entry, 242 of 371 (65%) patients had active uveitis; 60% (145/242, NRI) achieved quiescence at week 78, and 66% (95/143, as-observed) of those were corticosteroid free. At study entry, 129 of 371 (35%) patients had inactive uveitis; 74% (96/129, NRI) achieved quiescence at week 78, and 93% (89/96, as-observed) of those were corticosteroid free. Inflammatory lesions, anterior chamber grade, and vitreous haze grade showed initial improvement followed by decline in patients with active uveitis and remained stable in patients with inactive uveitis. BCVA improved in patients with active uveitis from weeks 0 to 78 (0.27 to 0.14 logMAR; left and right eyes; as-observed) and remained stable in patients with inactive uveitis. Mean corticosteroid dose decreased from 13.6 mg/day (week 0) to 2.6 mg/day (week 78) in patients with active uveitis and remained stable in those with inactive uveitis (1.5-1.2 mg/day). AEs (424 events/100 patient-years) and serious AEs (16.5 events/100 patient-years) were comparable with previous VISUAL trials.

CONCLUSIONS

Patients with active uveitis at study entry who received adalimumab therapy were likely to achieve quiescence, improve visual acuity, and reduce their daily uveitis-related systemic corticosteroid use. Most patients with inactive uveitis at study entry sustained quiescence without a systemic corticosteroid dose increase. No new safety signals were identified.

Randomized Controlled Study to Evaluate the Efficacy of Adalimumab in Patients with Different Forms of Refractory Uveitis

PURPOSE

TNF alpha inhibitors have revolutionized the care of vision-threatening uveitis. This study evaluated the efficacy of adalimumab (ADA) for the treatment of refractory noninfectious uveitis.

DESIGN

Randomized, prospective, controlled, two-center clinical trial Methods: Patients with active uveitis despite combined oral low-dose prednisolone and immunosuppression were randomized for additional ADA with corticosteroids in a fixed tapering regime, or corticosteroids only. Primary outcome measure at three months was improved best-corrected visual acuity (BCVA; >2 lines). In case of treatment failure, switch to the other arm was possible.

RESULTS

Twenty-five patients (10 ADA, 15 controls) were included. BCVA increased with ADA by > 2 lines in 6/10 patients (60%; mean increase of 0.23 logMAR), but in only 2/15 from controls (13%, mean increase of 0.04 logMAR, Fisher´s exact test p = 0.00221).

CONCLUSIONS

The results show superiority of ADA over controls in severe ocular inflammation including anterior uveitis.