Elevated serum levels of interleukin-17A in uveitis patients

Targeted therapies for uveitis in spondyloarthritis: A narrative review

Spondyloarthritis (SpA) encompasses a group of chronic inflammatory disorders of the joints frequently associated with uveitis in almost a quarter of cases. SpA-related uveitis typically affects the eye anterior chamber with sudden onset, causing pain, redness, photophobia, and blurred vision. Ophthalmologists will describe an acute anterior unilateral uveitis. Most patients present with episodic acute anterior non-granulomatous uveitis and retain excellent visual acuity. However, systemic treatments are recommended in the event of frequent relapses (2-3/year) or in rare cases of sight-threatening with ocular complications. The improved understanding of the pathogenesis of SpA has led to the management of this disease by biologics. Here, we review the main data regarding the opportunity to target specific components in inflammatory pathways for the treatment of SpA-related uveitis. These therapies are recommended for long-term control when uveitis relapses occur too frequently despite conventional systemic treatments. Significant benefits have been obtained with the tumor necrosis factor-α inhibitors (TNFis), particularly infliximab and adalimumab. Paradoxically, a high number of uveitis occurrences have been shown on etanercept. Mixed results have been demonstrated with interleukin-17 antagonists (secukinumab) and interleukin-12/interleukin-23 antagonists (ustekinumab) in cases of failure of TNFis. JAK inhibitors seem to be a valuable class of medications for these patients in the future. Although SpA-related uveitis is typically managed with conventional local and/or systemic treatments, these biological/targeted therapies may provide avenues to control both the underlying SpA and uveitis manifestations. Thus, a close collaboration between patients, rheumatologists, internists, and ophthalmologists is needed to optimally manage ocular inflammation in SpA.

Low uveitis rates in patients with axial spondyloarthritis treated with bimekizumab: pooled results from phase 2b/3 trials

OBJECTIVES

Acute anterior uveitis ('uveitis') is a common axial spondyloarthritis (axSpA) extramusculoskeletal manifestation. Interleukin (IL)-17 is implicated in its pathogenesis, however, there is conflicting evidence for IL-17A inhibition in uveitis management. We report pooled analyses of uveitis incidence in patients receiving bimekizumab (BKZ), a monoclonal IgG1 antibody that selectively inhibits IL-17F in addition to IL-17A, from phase 2b/3 trials.

METHODS

Data were pooled for patients receiving BKZ 160 mg or placebo in the double-blind treatment period of the phase 3 BE MOBILE 1 (NCT03928704; non-radiographic axSpA) and BE MOBILE 2 (NCT03928743; radiographic axSpA) trials. Data were separately pooled for patients treated with at least one BKZ dose in the BE MOBILE trials and their ongoing open-label extension (OLE; NCT04436640), and the phase 2b BE AGILE trial (NCT02963506; radiographic axSpA) and its ongoing OLE (NCT03355573). Uveitis rates and exposure-adjusted incidence rates (EAIR)/100 patient-years (PYs) are reported.

RESULTS

In the BE MOBILE 1 and 2 double-blind treatment period, 0.6% (2/349) of patients receiving BKZ experienced uveitis vs 4.6% (11/237) receiving placebo (nominal p=0.001; EAIR (95% CI): 1.8/100 PYs (0.2 to 6.7) vs 15.4/100 PYs (95% CI 7.7 to 27.5)). In patients with history of uveitis, EAIR was lower in patients receiving BKZ (6.2/100 PYs (95% CI 0.2 to 34.8); 1.9%) vs placebo (70.4/100 PYs (95% CI 32.2 to 133.7); 20.0%; nominal p=0.004). In the phase 2b/3 pool (N=848; BKZ exposure: 2034.4 PYs), EAIR remained low (1.2/100 PYs (95% CI 0.8 to 1.8)).

CONCLUSIONS

Bimekizumab, a dual-IL-17A/F inhibitor, may confer protective effects for uveitis in patients with axSpA.

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

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

Cytokines in PD-1 immune checkpoint inhibitor adverse events and implications for the treatment of uveitis

Immune checkpoint inhibitors (ICI) such as Programmed cell Death 1 (PD-1) inhibitors have improved cancer treatment by enhancing the immune system's ability to target malignant cells. Their use is associated with immune-related adverse events (irAEs), including uveitis. The profile of pro-inflammatory cytokines underlying Anti-PD-1-induced uveitis shares significant overlap with that of non-infectious uveitis. Current corticosteroid treatments for uveitis while effective are fraught with vision threatening side effects. The cytokine profile in ICI-related uveitis has a large overlap with that of noninfectious uveitis, this overlap strongly supports the potential for therapy that activates the PD-1 axis in the eye to treat uveitis. Indeed, ICI related uveitis often resolves with cessation of the ICI, restoring the endogenous PD-1 axis. The potential benefit of targeting many pro-inflammatory cytokines via local PD-1 axis activation is mitigating ocular inflammation while minimizing adverse effects.

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.

Psoriasis Comorbidities and Their Treatment Impact

Psoriasis, a systemic inflammatory disease classically presenting with cutaneous lesions, has significant involvement in other organ systems. This article explores the prevalence, clinical manifestations, screening mechanisms, and laboratory testing by which to evaluate these comorbidities. Treatment approach for these comorbidities must combine patient preference with established treatment algorithms while recognizing innovative therapeutics currently under development.

Generalized Pustular Psoriasis and Systemic Organ Dysfunctions

This review explores the intricate relationship between generalized pustular psoriasis (GPP) and various systemic diseases, shedding light on the broader impacts of this severe skin condition beyond its primary dermatological manifestations. GPP is identified as not only a profound contributor to skin pathology but also a significant risk factor for systemic diseases affecting cardiovascular, hepatic, renal, pulmonary, and skeletal systems, as well as associated with an increased incidence of anemia, depression, anxiety, and arthritis. The research highlights the complex interplay of cytokines, particularly IL-17 and IL-36, which are central to the pathophysiology of GPP and implicated in the exacerbation of systemic conditions. Key findings indicate a higher incidence of cardiovascular events in GPP patients compared to those with other severe forms of psoriasis, notably with a stronger correlation between myocardial infarction history and GPP development. Liver disturbances, frequently reversible upon psoriasis remission, suggest a cytokine-mediated link to hepatic health. Renal dysfunction appears elevated in GPP sufferers, with IL-17 and IL-36 potentially driving renal fibrosis. Similarly, interstitial lung disease and osteoporosis in GPP patients underscore the systemic reach of inflammatory processes initiated in the skin. The associations with anemia, depression, anxiety, and arthritis further complicate the clinical management of GPP, requiring a multidisciplinary approach. The study concludes that managing GPP effectively requires a holistic approach that addresses both the cutaneous and systemic dimensions of the disease, advocating for continued research into the mechanisms that connect GPP with broader health implications to refine therapeutic strategies.

Questionnaire survey of risk factors for recurrence of ocular inflammation in patients with uveitis after SARS-CoV-2 infection

Introduction

During the COVID-19 pandemic in China, the proportion of patients with uveitis who were infected with SARS-CoV-2 increased greatly. The impact of SARS-CoV-2 infection on patients with uveitis has not been fully described.

Methods

A questionnaire on SARS-CoV-2 infection was sent to patients with uveitis to assess ocular and systemic conditions before and after infection. Chi-square analysis and multifactorial regression analysis were used to investigate the associations between each risk factor and the recurrence of uveitis after SARS-CoV-2 infection.

Results

One hundred thirty-nine patients with noninfectious uveitis completed the questionnaire; 114 (82.0%) had COVID-19, and 27 (23.7%) had recurrent or exacerbated uveitis after COVID-19. There was a higher rate of recurrence or aggravation of ocular inflammation in patients who developed severe COVID-19 symptoms (severe group 8/20 vs. nonsevere group 19/94). There were significant differences in the rates of recurrence and aggravation between the two groups of patients who differed in terms of ocular inflammatory activity within 3 months prior to SARS-CoV-2 infection (χ2 = 10.701, P=0.001), as well as in the rates of recurrence and aggravation after cessation of systemic immunomodulatory therapy. After multifactorial regression analysis, patients with active ocular inflammation within 3 months prior to SARS-CoV-2 infection had a greater risk of recurrence or exacerbation of uveitis after COVID-19 (OR=4.298, P=0.002).

Conclusion

The degree of ocular inflammatory activity within 3 months prior to SARS-CoV-2 infection may be a major factor influencing the recurrence or exacerbation of uveitis after infection. Interruption of medication should be minimized in patients with unstable inflammatory control.

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.

Recent advances in uveitis therapy: focus on selected phase 2 and 3 clinical trials

INTRODUCTION

Uveitis is a heterogeneous group of ocular conditions characterized by inflammation of the uveal tract. It is a leading cause of blindness in developed countries and exerts significant psychological, social, and economic impact on both patients and the larger society. While there are numerous pharmacotherapy options, posterior segment noninfectious uveitis remains a significant challenge to treat due to its severity, chronicity, and high recurrence rates.

AREAS COVERED

The index review highlights the unmet needs of uveitis pharmacotherapy and its research and the shortcomings of existing ocular and systemic therapeutic options for noninfectious uveitis. The more promising novel ocular drug delivery methods and therapeutic targets/drugs are discussed, and evidence from the clinical trials is evaluated.

EXPERT OPINION

There has been incredible growth in the number of treatment options available to uveitis patients today, especially with the new generation of biologic drugs. Available evidence suggests that these newer options may be superior to conventional immunosuppressive therapies in terms of efficacy and side effect profiles. Further high-quality research and additional clinical trials will be needed to clarify their roles in the stepladder treatment approach of noninfectious uveitis.

Involvement of the systemic microcirculation in pediatric uveitis

BACKGROUND

Pediatric uveitis is a severe inflammatory ocular condition that can lead to sight-threatening complications and can negatively impact quality of life. The retinal microcirculation is often affected in intermediate uveitis and panuveitis. Here, we examined the extraocular (i.e., systemic) microcirculation in pediatric uveitis cases and healthy controls using nailfold capillaroscopy (NFC).

METHODS

We performed NFC in 119 children with noninfectious uveitis and 25 healthy pediatric controls, and assessed the following parameters: capillary density (number of capillaries/mm), dilated capillaries (apex > 20 µm), avascular area, the presence of microhemorrhages, and capillary morphology. Differences in NFC parameters between cases and controls were calculated using regression analysis after adjusting for age and sex.

RESULTS

The mean (± SD) age of the patient group was 13.7 (± 3) years, with 56% females; 46%, 18%, and 36% of cases presented as anterior uveitis, intermediate uveitis, and panuveitis, respectively, with an overall mean disease duration of 4.7 (± 4.0) years. Compared to the control group, the pediatric uveitis cases had a significantly higher number of dilated capillaries/mm and a higher prevalence of ramified capillaries. Moreover, compared to the control group the intermediate uveitis cases had a significantly higher number of dilated capillaries, whereas the anterior uveitis cases had a lower capillary density and a higher prevalence of ramified capillaries.

CONCLUSIONS

Children with uveitis without systemic disease can present with changes in systemic microcirculation. These changes vary amongst the subtypes of uveitis.

Izokibep: Preclinical development and first-in-human study of a novel IL-17A neutralizing Affibody molecule in patients with plaque psoriasis

Psoriasis, an immune-mediated inflammatory disease, affects nearly 125 million people globally. The interleukin (IL)-17A homodimer is a key driver of psoriasis and other autoimmune diseases, including psoriatic arthritis, axial spondyloarthritis, hidradenitis suppurativa, and uveitis. Treatment with monoclonal antibodies (mAbs) against IL-17A provides an improvement in the Psoriasis Area and Severity Index compared to conventional systemic agents. In this study, the AffibodyⓇ technology was used to identify and optimize a novel, small, biological molecule comprising three triple helical affinity domains, izokibep (previously ABY-035), for the inhibition of IL-17A signaling. Preclinical studies show that izokibep, a small 18.6 kDa IL-17 ligand trap comprising two IL-17A-specific Affibody domains and one albumin-binding domain, selectively inhibits human IL-17A in vitro and in vivo with superior potency and efficacy relative to anti-IL-17A mAbs. A Phase 1 first-in-human study was conducted to establish the safety, pharmacokinetics, and preliminary efficacy of izokibep, when administered intravenously and subcutaneously as single doses to healthy subjects, and as single intravenous and multiple subcutaneous doses to patients with psoriasis (NCT02690142; EudraCT No: 2015-004531-13). Izokibep was well tolerated with no meaningful safety concerns identified in healthy volunteers and patients with psoriasis. Rapid efficacy was seen in all psoriasis patients after one dose which further improved in patients receiving multiple doses. A therapeutic decrease in joint pain was also observed in a single patient with concurrent psoriatic arthritis. The study suggests that izokibep has the potential to safely treat IL17A-associated diseases such as psoriasis, psoriatic arthritis, axial spondyloarthritis, hidradenitis suppurativa, and uveitis.

T cells in ocular autoimmune uveitis: Pathways and therapeutic approaches

Autoimmune uveitis is a non-infectious intraocular condition that affects the uveal tract of the eye and threatens vision if not treated properly. Increasing evidence suggests that activated CD4⁺ T cells are associated with progressive and permanent destruction of photoreceptors in ocular autoimmune diseases. As such, the purpose of this review is to offer an overview of the role of CD4⁺ T cells in autoimmune uveitis as well as a justification for the current development and assessment of innovative autoimmune uveitis medications targeting CD4⁺ T cells. With an emphasis on T helper (Th)17, Th1, and Th2 cells, follicular helper CD4⁺ T cells, and regulatory T cells, this review presents a summary of recent research related to the pathways and signaling that encourage CD4⁺ T cells to develop into specialized effector cells. We also describe immunotherapeutic approaches based on CD4⁺ T cell subsets and their potential as therapeutic agents for autoimmune disorders.

Correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis

PURPOSE

To determine the correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis (OTB).

METHODS

Vitreous fluid was analysed for cytokines in patients with OTB and non-OTB uveitis using multiplex fluorescent bead-based flow cytometric assay. The clinical phenotypes were recorded and correlated with vitreous biomarkers.

RESULTS

Vitreous humour from OTB patients had elevated levels of interleukin-10 (IL-10), IL-17-A, interferon-gamma (IFN-γ), and tumour necrosis factor-alpha (TNF-α). Angiopoietin (Ang-2) levels were higher in the panuveitis phenotype. OTB posterior uveitis phenotype had relatively higher vascular endothelial growth factor (VEGF) levels and lower fibroblast growth factor (FGF) levels. Additionally, eyes with choroiditis and vasculitis had elevated levels of VEGF and Ang-2 with FGF downregulation. Both IFN-γ and IL-10 were upregulated in the choroiditis phenotype of OTB.

CONCLUSION

Angiogenic growth factors and inflammatory cytokines were altered in the vitreous humour of OTB patients. IFN-γ, VEGF, and IL-10 levels are increased in choroiditis and vasculitis phenotypes. Receiver operating characteristic (ROC) curve analysis further emphasized the importance of the IFN-γ assay in the diagnosis of OTB.

Non-biologic, steroid-sparing therapies for non-infectious intermediate, posterior, and panuveitis in adults

BACKGROUND

Non-infectious intermediate, posterior, and panuveitis (NIIPPU) represent a heterogenous collection of autoimmune and inflammatory disorders isolated to or concentrated in the posterior structures of the eye. Because NIIPPU is typically a chronic condition, people with NIIPPU frequently require treatment with steroid-sparing immunosuppressive therapy. Methotrexate, mycophenolate, cyclosporine, azathioprine, and tacrolimus are non-biologic, disease-modifying antirheumatic drugs (DMARDs) which have been used to treat people with NIIPPU.

OBJECTIVES

To compare the effectiveness and safety of selected DMARDs (methotrexate, mycophenolate mofetil, tacrolimus, cyclosporine, and azathioprine) in the treatment of NIIPPU in adults.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register), MEDLINE, Embase, the Latin American and Caribbean Health Sciences database, ClinicalTrials.gov, and the World Health Organization International Clinical Trials Registry Platform, most recently on 16 April 2021.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing selected DMARDs (methotrexate, mycophenolate, tacrolimus, cyclosporine, and azathioprine) with placebo, standard of care (topical steroids, with or without oral steroids), or with each other.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 11 RCTs with a total of 601 participants in this review. DMARDs versus control Two studies compared an experimental DMARD (cyclosporine A or enteric-coated mycophenolate [EC-MPS]) plus oral steroid with steroid monotherapy. We did not pool these results into a meta-analysis because the dose of cyclosporine used was much higher than that used in current clinical practice. The evidence is very uncertain about whether EC-MPS plus low-dose oral steroid results in a higher proportion of participants achieving control of inflammation over steroid monotherapy (risk ratio [RR] 2.81, 95% confidence interval [CI] 1.10 to 7.17; 1 study, 41 participants; very low-certainty evidence). The change in best-corrected visual acuity (BCVA) was reported separately for right and left eyes. The evidence for improvement (lower logarithm of the minimum angle of resolution (logMAR) indicates better vision) between the groups is very uncertain (mean difference [MD] -0.03 and -0.10, 95% CI -0.96 to 0.90 and -0.27 to 0.07 for right and left, respectively; 1 study, 82 eyes; very low-certainty evidence). No data were available for the following outcomes: proportion of participants achieving a 2-line improvement in visual acuity, with confirmed macular edema, or achieving steroid-sparing control. The evidence for the proportion of participants requiring cessation of medication in the DMARD versus control group is very uncertain (RR 2.61, 95% CI 0.11 to 60.51; 1 study, 41 participants; very low-certainty evidence). Methotrexate versus mycophenolate We were able to combine two studies into a meta-analysis comparing methotrexate versus mycophenolate mofetil. Methotrexate probably results in a slight increase in the proportion of participants achieving control of inflammation, including steroid-sparing control, compared to mycophenolate at six months (RR 1.23, 95% CI 1.01 to 1.50; 2 studies, 261 participants; moderate-certainty evidence). Change in BCVA was reported per eye and the treatments likely result in little to no difference in change in vision (MD 0.01 logMAR higher [worse] for methotrexate versus mycophenolate; 2 studies, 490 eyes; moderate-certainty evidence). No data were available for the proportion of participants achieving a 2-line improvement in visual acuity. The evidence is very uncertain regarding the proportion of participants with confirmed macular edema between methotrexate versus mycophenolate (RR 0.49, 95% CI 0.19 to 1.30; 2 studies, 35 eyes; very low-certainty). Methotrexate versus mycophenolate may result in little to no difference in the proportion of participants requiring cessation of medication (RR 0.99, 95% CI 0.43 to 2.27; 2 studies, 296 participants; low-certainty evidence). Steroids with or without azathioprine versus cyclosporine A Four studies compared steroids with or without azathioprine (oral steroids, intravenous [IV] steroids, or azathioprine) to cyclosporine A. We excluded two studies from the meta-analysis because the participants were treated with 8 mg to 15 mg/kg/day of cyclosporine A, a significantly higher dose than is utilized today because of concerns for nephrotoxicity. The remaining two studies were conducted in all Vogt-Koyanagi-Harada disease (VKH) populations and compared cyclosporine A to azathioprine or IV pulse-dose steroids. The evidence is very uncertain for whether the steroids with or without azathioprine or cyclosporine A influenced the proportion of participants achieving control of inflammation (RR 0.84, 95% CI 0.70 to 1.02; 2 studies, 112 participants; very low-certainty evidence), achieving steroid-sparing control (RR 0.64, 95% CI 0.33 to 1.25; 1 study, 21 participants; very low-certainty evidence), or requiring cessation of medication (RR 0.85, 95% 0.21 to 3.45; 2 studies, 91 participants; very low-certainty evidence). The evidence is uncertain for improvement in BCVA (MD 0.04 logMAR lower [better] with the steroids with or without azathioprine versus cyclosporine A; 2 studies, 91 eyes; very low-certainty evidence). There were no data available (with current cyclosporine A dosing) for the proportion of participants achieving a 2-line improvement in visual acuity or with confirmed macular edema. Studies not included in synthesis We were unable to include three studies in any of the comparisons (in addition to the aforementioned studies excluded based on historic doses of cyclosporine A). One was a dose-response study comparing cyclosporine A to cyclosporine G, a formulation which was never licensed and is not clinically available. We excluded another study from meta-analysis because it compared cyclosporine A and tacrolimus, considered to be of the same class (calcineurin inhibitors). We were unable to combine the third study, which examined tacrolimus monotherapy versus tacrolimus plus oral steroid, with any group.

AUTHORS' CONCLUSIONS

There is a paucity of data regarding which DMARD is most effective or safe in NIIPPU. Studies in general were small, heterogenous in terms of their design and outcome measures, and often did not compare different classes of DMARD with each other. Methotrexate is probably slightly more efficacious than mycophenolate in achieving control of inflammation, including steroid-sparing control (moderate-certainty evidence), although there was insufficient evidence to prefer one medication over the other in the VKH subgroup (very low-certainty evidence). Methotrexate may result in little to no difference in safety outcomes compared to mycophenolate.

Increased Risk of Acute Coronary Syndrome in Ankylosing Spondylitis Patients With Uveitis: A Population-Based Cohort Study

Background

Uveitis, a sight-threatening ocular inflammatory state, is associated with autoimmune diseases and systemic inflammation. This prolonged systemic inflammation may cause plaque formation in coronary arteries, subsequently resulting in acute coronary syndrome (ACS).

Methods

This retrospective, population-based study (15-year period) used the Longitudinal Health Insurance Database based on the National Health Insurance Research Database in Taiwan. Chi-square and Student's t-tests were used to examine differences between the study and comparison cohorts for categorical and continuous variables, respectively. Fine and Gray's competing risk model was used to determine the hazard ratio of the risk of ACS. Furthermore, the cumulative risk of ACS was determined using Kaplan-Meier analysis.

Results

A total of 1,111 patients with AS and uveitis were enrolled in this study cohort, and 4,444 patients with AS without uveitis were enrolled in the comparison cohort. After adjustment for age, sex, and comorbidities, patients with AS and uveitis demonstrated an increased risk of ACS compared to those without uveitis (adjusted hazard ratio: 1.675, p<0.001). In addition, Kaplan-Meier analysis revealed that patients with AS and uveitis had a significantly higher risk of ACS than those without uveitis (p<0.001). Age, diabetes mellitus, hypertension, hyperlipidemia, chronic obstructive pulmonary disease, asthma, and systemic steroids were significant risk factors for ACS. Both anterior uveitis and posterior segment involvement were associated with an increased risk of ACS in patients with AS. All-cause mortality was higher in the uveitis group (9.81%) than in the non-uveitis group (8.10%) (p=0.015).

Conclusion

Our analysis revealed that uveitis could potentially be a predictor of ACS in patients with AS. However, further prospective controlled studies are required to assess the association between uveitis and ACS in patients with AS.

Therapie der Uveitis mit Biologika

Zielsetzung Ziel dieser Zusammenfassung ist das Vermitteln einer Übersicht zu den verschiedenen Ansatzpunkten, Wirkmechanismen und Indikationen diverser Biologika, die bei der Therapie der nichtinfektiösen Uveitis zum Einsatz kommen.

Material und Methoden Etablierte sowie aktuelle Literatur wurden herangezogen, um die biochemischen und pathophysiologischen Grundlagen sowie eine evidenzbasierte Empfehlung zum Therapieeinsatz verschiedener Biologika bei nichtinfektiöser Uveitis allgemein und bei speziellen Uveitisentitäten darzulegen.

Ergebnisse Für viele Biologika, hier nennenswert TNF-α-Inhibitoren, einige Interleukininhibitoren, Interferone sowie B- und T-Zell-Inhibitoren, liegen mittlerweile gute Daten vor, was ihren Einsatz in der Uveitistherapie mehr als rechtfertigt. Dies trifft insbesondere für den TNF-α-Inhibitor Adalimumab zu, welcher der einzig zugelassene Vertreter für diese Indikation unter den vorgestellten Biologika ist.

Schlussfolgerungen Die Biologika haben die Behandlung der Uveitis revolutioniert und sind aus der aktuellen Therapie der intraokularen Entzündung nicht mehr wegzudenken. Biologika werden bei Ineffektivität oder Unverträglichkeit konventioneller immunsuppressiver Medikamente empfohlen, aber auch bei der Therapie von schwerwiegenden Uveitisformen (z. B. Morbus Behçet). Die TNF-α-Inhibitoren sind die am häufigsten verwendeten Biologika bei Uveitis.

Uveitis as a Risk Factor for Developing Acute Myocardial Infarction in Ankylosing Spondylitis: A National Population-Based Longitudinal Cohort Study

Background

Ankylosing spondylitis (AS) is a chronic inflammatory disease. Excess cardiovascular risks were well recognized in patients with AS and were attributed to prolonged systemic inflammation. Uveitis is one of the most common extra-articular symptoms of AS and is also considered an indicator of systemic inflammation. This study aimed to investigate whether uveitis was a risk factor for developing acute myocardial infarction (AMI) in patients with AS using the National Health Insurance Research Database (NHIRD).

Methods

Data were collected from the NHIRD over a fifteen-year period. Variables were analyzed using the Pearson chi-square test and Fisher’s exact test. Risk factors for the occurrence of AMI were examined by calculating hazard ratio. Kaplan-Meier analysis was performed to compare the cumulative incidence of AMI in the uveitis and non-uveitis cohorts.

Results

A total of 5905 patients with AS were enrolled, including 1181 patients with uveitis (20%) and 4724 patients without uveitis (80%). The Kaplan–Meier method with the log-rank test showed that the uveitis group had a significantly higher cumulative hazard for patients with AMI than the non-uveitis group (p < 0.001). The adjusted hazard ratio (aHR) of AMI was higher in the uveitis group than in the non-uveitis group (aHR = 1.653, p < 0.001). Stratified analysis revealed that patients with uveitis had an increased risk of developing AMI regardless of their sex (male/female aHR = 1.688/1.608, p < 0.001). Patients with uveitis in all age groups were independently associated with an increased risk of developing AMI compared to those without uveitis (20–39 years/40–59 years/≥ 60 years, aHR = 1.550, 1.579, 3.240, p < 0.001). Patients with uveitis had a higher probability of developing AMI regardless of comorbidities. Uveitis patients with comorbidities had a higher risk of developing AMI compared to uveitis patients without comorbidities.

Conclusion

Uveitis is a significant risk factor for developing AMI in patients with AS. Physicians should be aware of the potential cardiovascular risk in AS patients with uveitis, especially simultaneously with other traditional risk factors of AMI. Further prospective studies are needed to elucidate the underlying mechanism between uveitis and AMI in patients with AS.

The role of IL-17 and anti-IL-17 agents in the immunopathogenesis and management of autoimmune and inflammatory diseases

Interleukin-17 (IL-17) is a proinflammatory cytokine involved in chronic inflammation occurring during the pathogenesis of allergy, malignancy, and autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, multiple sclerosis, and psoriasis. IL-17 is produced by multiple cell types of adaptive and innate immunity, including T helper 17 cells, CD8 + T cells, γδ T cells, natural killer T cells, and innate lymphoid cells. Monoclonal antibodies (mAbs) targeting IL-17 and/or IL-17R would be a potential approach to study this therapeutic tool for these diseases. In the current review, we aimed to highlight the characteristics of IL-17 and its important role in the pathogenesis of related diseases. Critical evaluation of the mAbs targeting IL-17A and IL-17 receptors (e.g., Ixekizumab, Secukinumab, and Brodalumab) in various immune-mediated diseases will be provided, and finally, their clinical efficacy and safety will be reported.

Managing Psoriatic Arthritis With Inflammatory Bowel Disease and/or Uveitis

Psoriatic arthritis (PsA) is a chronic inflammatory disease that presents with psoriasis (PsO), peripheral and axial arthropathy. The heterogeneity of disease presentation leads to the term "psoriatic disease (PsD)" which is thought to better encompass the range of clinical manifestations. PsA is associated with several comorbidities such as cardiovascular diseases, metabolic syndrome and other extra-articular manifestations including uveitis, and inflammatory bowel disease (IBD). While novel therapeutics are being developed following advances in our understanding of the pathogenesis of the disease, the diverse combinations of PsA with its various comorbidities still pose a clinical challenge in managing patients with PsA. This article reviews our current understanding of the pathogenesis of PsA and how various pathways in the pathogenesis lead to the two comorbid extra-articular manifestations - uveitis and IBD. We also review current evidence of treatment strategies in managing patients with PsA with comorbidities of uveitis and/or IBD.

IL-17A Damages the Blood-Retinal Barrier through Activating the Janus Kinase 1 Pathway

Blood-retinal barrier (BRB) dysfunction underlies macular oedema in many sight-threatening conditions, including diabetic macular oedema, neovascular age-related macular degeneration and uveoretinitis. Inflammation plays an important role in BRB dysfunction. This study aimed to understand the role of the inflammatory cytokine IL-17A in BRB dysfunction and the mechanism involved. Human retinal pigment epithelial (RPE) cell line ARPE19 and murine brain endothelial line bEnd.3 were cultured on transwell membranes to model the outer BRB and inner BRB, respectively. IL-17A treatment (3 days in bEnd.3 cells and 6 days in ARPE19 cells) disrupted the distribution of claudin-5 in bEnd.3 cells and ZO-1 in ARPE19 cells, reduced the transepithelial/transendothelial electrical resistance (TEER) and increased permeability to FITC-tracers in vitro. Intravitreal (20 ng/1 μL/eye) or intravenous (20 ng/g) injection of recombinant IL-17A induced retinal albumin leakage within 48 h in C57BL/6J mice. Mechanistically, IL-17A induced Janus kinase 1 (JAK1) phosphorylation in bEnd.3 but not ARPE19 cells. Blocking JAK1 with Tofacitinib prevented IL-17A-mediated claudin-5 dysmorphia in bEnd.3 cells and reduced albumin leakage in IL-17A-treated mice. Our results suggest that IL-17A can damage the BRB through the activating the JAK1 signaling pathway, and targeting this pathway may be a novel approach to treat inflammation-induced macular oedema.

Interleukins and cytokine biomarkers in uveitis

Interleukins and cytokines are involved in the pathogenesis of uveitis of heterogeneous origin. Understanding the basics of the ocular immune privilege is a fulcrum to discern their specific role in diverse uveitis to potentially translate as therapeutic targets. This review attempts to cover these elements in uveitis of infectious, noninfectious and masquerade origin. Insights of the molecular targets in novel therapy along with the vision of future research are intriguing.

Immune-Mediated Retinal Vasculitis in Posterior Uveitis and Experimental Models: The Leukotriene (LT)B4-VEGF Axis

Retinal vascular diseases have distinct, complex and multifactorial pathogeneses yet share several key pathophysiological aspects including inflammation, vascular permeability and neovascularisation. In non-infectious posterior uveitis (NIU), retinal vasculitis involves vessel leakage leading to retinal enlargement, exudation, and macular oedema. Neovascularisation is not a common feature in NIU, however, detection of the major angiogenic factor—vascular endothelial growth factor A (VEGF-A)—in intraocular fluids in animal models of uveitis may be an indication for a role for this cytokine in a highly inflammatory condition. Suppression of VEGF-A by directly targeting the leukotriene B4 (LTB4) receptor (BLT1) pathway indicates a connection between leukotrienes (LTs), which have prominent roles in initiating and propagating inflammatory responses, and VEGF-A in retinal inflammatory diseases. Further research is needed to understand how LTs interact with intraocular cytokines in retinal inflammatory diseases to guide the development of novel therapeutic approaches targeting both inflammatory mediator pathways.

Ocular Complications of Checkpoint Inhibitors and Immunotherapeutic Agents: A Case Series

BACKGROUND

Ophthalmologists have a role in assessing immune-related adverse events (IRAE) in oncology patients on immunotherapy. We assessed the utility of a hospital-wide toxicity team in referring patients with new ocular symptoms for examination. We also identified new immunotherapy agents causing ocular side-effects.

DESIGN

A cohort study of eight consecutive patients on immunotherapy, who developed ocular IRAE from November 1, 2017 to June 30, 2019. All were seen at the Ocular Immunology Division of the Wilmer Eye Institute and referred by the Johns Hopkins Toxicity Team.

RESULTS

All eight patients on had IRAEs; were treated with corticosteroid drops or observation with clinical resolution. Two new agents, epocadostat and daratumumab, were associated with the development of uveitis.

CONCLUSION

Ophthalmologists play an important role in a hospital-wide toxicity team and need to include IRAEs in their differential diagnosis. Given new drug development, ophthalmologists may be the first to identify IRAEs.

Psoriasis and uveitis: links and risks

Uveitis, an inflammatory disorder of the mid-portion of the eye, is considered a relatively rare but very serious ocular complication of psoriasis. Data on the specific characteristics of uveitis in the background of psoriasis are extremely limited. The presence of uveitis in the context of psoriasis has been estimated to occur in 7-20% of the psoriasis cases. This incidence tends to be higher in patients suffering from psoriasis and psoriatic arthritis (PsA) or PSA alone. Psoriatic uveitis is usually bilateral, chronic, and severe. In term of pathogenesis, both psoriasis and uveitis are considered as paradigms of T-helper 1/T-helper 17 (Th1/Th17) inflammatory reactions. Certain cytokines such as tumor necrosis factor-α (TNF- α), Interleukin-17 (IL-17), IL-23, and IL-6 play a significant role in the pathogenesis of both psoriasis and uveitis. As uveitis shares common pathogenetic mechanisms with psoriasis in certain circumstances, both diseases may benefit from the same targeted biologic therapies. Undiagnosed and under-treated cases of psoriatic uveitis may cause significant morbidity and even vision loss. Larger prospective studies are needed in order to further investigate the association between these two entities.

Defining outcome measures in juvenile idiopathic arthritis associated uveitis by a systematic review analysis: do we need a consensus?

BACKGROUND

Juvenile Idiopathic Arthritis associated Uveitis (JIA-U) represents its most frequent extra-articular manifestation and the main cause of childhood uveitis in in developed countries. The broad variety of outcome measures utilized makes the comparison of the disease course, risk for complications, impairment in visual function, and responses to treatment quite difficult. Our aim was to summarize evidence regarding the current availability of outcome measures in JIA-U.

METHODS

A systematic review between January 2000 and December 2018 was performed to identify studies investigating outcome measures used in JIA-U.

RESULTS

The initial search identified 8254 articles of which 89 were potentially eligible. After the full text revision, a total of 27 studies, including 2 RCTs, were included. Among these studies 12 outcome measures for JIA-U use have been identified (grade of cells in the AC, grade of flare in the AC, VA, amblyopia, structural complications, use and sparing of oral corticosteroids and immunosuppressive drugs, surgery requirement, biomarkers, bilateral disease, JIA persistence, quality of life assessments, uveitis subtype). As regards primary outcome measures, 44% among studies included one or more variables related to disease activity (i.e. grade of flare, grade of cells); 56% included visual function performance (i.e. visual acuity); 68% (17/25) included one or more variables of disease-associated tissue damage or complications (i.e. cataract, amblyopia); 24% included disease features (i.e. bilateral disease; uveitis subtype); 44% included laboratory features (i.e. biomarkers); 8% included JIA features (i.e. persistence of disease); 12% included quality of life (i.e. EYE-Q); 44% included management (i.e. use and sparing of oral corticosteroids and other immunosuppressive drugs; surgery requirement).

CONCLUSIONS

Our systematic review surveys the heterogeneity around outcome measures related to JIA-U in children, even in RCTs. It does not provide the solution to overcome the heterogeneity in uveitis studies, but it does provide an estimate of the scale of the problems and provides data to inform this important debate; highlighting the requirement to obtain a new consensus regarding a common approach to identify suitable and efficient outcome measures in JIA-U.

Targeting Interleukin-23 in the Treatment of Noninfectious Uveitis

The interleukin (IL)-23/IL-17 axis plays a central role in the pathogenesis of immune-mediated diseases such as psoriasis, psoriatic arthritis, Crohn's disease, and uveitis. Therefore, targeting the IL-23/IL-17 axis has become the focus of multiple clinical trials for drug development in patients with autoimmune diseases. We briefly describe the biology of the IL-23/IL-17 axis and its relevance to the pathogenesis of experimental and clinical uveitis, and review the monoclonal antibody therapies targeting this pathway. Finally, 2 ongoing phase 2 trials of the anti-IL-23 biologic therapy ustekinumab (STELARA, Janssen Biotech Inc, Horsham, PA) in patients with noninfectious uveitis are introduced.

Cytokines in uveitis

PURPOSE OF REVIEW

Increasing evidence supports Th17 cells as key mediators of ocular inflammatory disease. Cytokines that are important for the development and pathologic function of these cells are potential therapeutic targets in patients with immune mediated uveitis. This review provides an overview of these cytokines including recent insights about their roles in ocular inflammation from laboratory and clinical studies.

RECENT FINDINGS

Interleukin (IL)-6, IL-10, IL-17, IL-22, IL-23 and tumour necrosis factor-alpha (TNFα) are cytokines that have been examined for their functional role in uveitis and their relationship to pathologic Th17 cells. Studies in animal models, particularly in experimental autoimmune uveitis (EAU), have been instrumental in studying the role of these cytokines in disease pathogenesis. More recently, studies on aqueous, vitreous and serum from patients with uveitis using flow cytometry and multiplex ELISA bead-based methodologies have provided insights into the contribution of Th17 cells and the related cytokines in ocular inflammatory diseases. The central role of IL-23 in determining the pathologic Th17 fate has made it an effective therapeutic target in systemic diseases such as psoriasis and thereby an attractive potential target for patients with immune-mediated uveitis.

SUMMARY

Th17 cells, and their related cytokines, are important inflammatory mediators in autoimmune uveitis. Animal and human studies continue to provide new information to direct development of new cytokine-targeted therapies for patients with uveitis.

Elevated serum levels of IL-6 and CXCL9 in autoimmune retinopathy (AIR) patients

Autoimmune retinopathy (AIR) is a rare immune-mediated retinopathy associated with circulating antiretinal antibodies (ARAs). Other prominent features of AIR include visual field deficits and photoreceptor dysfunction in the setting of progressive unexplained vision loss. The role of inflammation is poorly understood in AIR. Since cytokines play a central role in the initiation and development of inflammation, we evaluated the presence of proinflammatory cytokines and chemokines in AIR patient sera. We demonstrate that IL-6 and CXCL9 are both elevated in AIR patient sera. Moreover, the presence and concentration of these 2 molecules appear to correlate with AIR patient disease severity. This cytokine profile, IL-6 and CXCL9, has been described to participate in a variety of autoimmune and inflammatory diseases. Our study provides support for an activated inflammatory process in AIR and identifies possible mechanisms that can drive autoimmunity in this disease.

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IL-6 and CXCL9 are both elevated in AIR patient sera.

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The presence and concentration of IL-6 and CXCL9 correlate with AIR patient disease severity.

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These cytokines may play a prominent role in the initiation and development of inflammation and autoimmunity.

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The data provides evidence for activated inflammatory processes in AIR.

Roles of interleukin-17 in uveitis

Th17 cells, a CD4+ T-cell subset, produce interleukin (IL)-17, a pro-inflammatory cytokine that has been shown to be involved in several forms of infectious and noninfectious uveitis. Here, we explore the roles of this IL in uveitic disorders as well as in experimental autoimmune uveitis, the possible pathogenic implications of several cytokines associated with IL-17 and analyze the current outcomes and goals for drugs aiming for the IL-17 pathway.

[Cytokine profile changes in children with juvenile idiopathic arthritis-associated uveitis]

AIM

to identify the differences between serum cytokine profiles in juvenile idiopathic arthritis (JIA) with or without uveal tract inflammation.

MATERIAL AND METHODS

Serum cytokine profiles were studied in two groups of patients: 20 children with JIA and JIA-associated uveitis and 33 children, who had no signs of uveitis under basic therapy for their JIA. All the patients showed drug remission of articular syndrome. Inflammation of the choroid took the form of chronic anterior uveitis. The process was active in 95% of cases. The control group consisted of 35 children without rheumatic disease or other acute condition at the time of examination. Groups were comparable in terms of age and sex. Serum levels of TNF-α, IFN-γ, IL-17, IL-10 were measured by the enzyme multiplied immunoassay technique.

RESULTS

A statistically significant increase in TNF-α, IFN-γ, IL-17, and IL-10 levels was found in all patients as compared to the control group. A comparison drawn between serum cytokine levels of JIA patients and those, who also suffered from JIA-associated uveitis, revealed a decrease in IFN-γ and an increase in IL-10 in the latter group. There was also a statistically significant positive correlation between TNF-α and IFN-γ serum levels in patients with JIA-associated uveitis.

CONCLUSION

Development of uveitis in patients with drug remission of JIA occurs on the background of cytokine imbalance in the serum, in particular, increased concentrations of proinflammatory TNF-α and IL-17 cytokines along with reduced IFN-γ and increased IL-10 levels. This may be regarded as risk factors for ocular inflammation and should be taken into account when making treatment decisions.

Autoimmune uveitis: clinical, pathogenetic, and therapeutic features

Autoimmune uveitis (AU), an inflammatory non-infectious process of the vascular layer of the eye, can lead to visual impairment and, in the absence of a timely diagnosis and suitable therapy, can even result in total blindness. The majority of AU cases are idiopathic, whereas fewer than 20 % are associated with systemic diseases. The clinical severity of AU depends on whether the anterior, intermediate, or posterior part of the uvea is involved and may range from almost asymptomatic to rapidly sight-threatening forms. Race, genetic background, and environmental factors can also influence the clinical picture. The pathogenetic mechanism of AU is still poorly defined, given its remarkable heterogeneity and the many discrepancies between experimental and human uveitis. Even so, the onset of AU is thought to be related to an aberrant T cell-mediated immune response, triggered by inflammation and directed against retinal or cross-reactive antigens. B cells may also play a role in uveal antigen presentation and in the subsequent activation of T cells. The management of AU remains a challenge for clinicians, especially because of the paucity of randomized clinical trials that have systematically evaluated the effectiveness of different drugs. In addition to topical treatment, several different therapeutic options are available, although a standardized regimen is thus far lacking. Current guidelines recommend corticosteroids as the first-line therapy for patients with active AU. Immunosuppressive drugs may be subsequently required to treat steroid-resistant AU and for steroid-sparing purposes. The recent introduction of biological agents, such as those targeting tumor necrosis factor-α, is expected to remarkably increase the percentages of responders and to prevent irreversible sight impairment. This paper reviews the clinical features of AU and its crucial pathogenetic targets in relation to the current therapeutic perspectives. Also, the largest clinical trials conducted in the last 12 years for the treatment of AU are summarized and critically discussed.

Increased CD1c+ mDC1 with mature phenotype regulated by TNFα-p38 MAPK in autoimmune ocular inflammatory disease

In this study we investigated the role of blood CD1c(+) myeloid dendritic cells 1 (mDC1), a key mDC subtype, in patients with autoimmune uveitis. We observed a significant increase of blood CD1c(+) mDC1 in uveitis patients. The increased CD1c(+) mDC1 exhibited high HLADR expression and less antigen uptake. CD1c(+) mDC1 were divided into two subpopulations. CD1c(hi) mDC1 subpopulation showed less antigen uptake and higher HLADR expression compared to CD1c(lo) mDC1 subpopulation. Importantly, the CD1c(hi) mDC1 subpopulation was increased in uveitis patients. In vitro, mature monocyte-derived dendritic cells (MoDCs), characterized by lower levels of antigen uptake, induced more CD4(+)CD62L(-) T helper cell proliferation. The mature phenotype and function of CD1c(+) mDC1 were regulated by TNFα via a p38 MAPK-dependent pathway. These data show that alterations in the systemic immune response are involved in the pathogenesis of autoimmune uveitis and invite the therapeutic possibility of attenuating uveitis by manipulating blood CD1c(+) mDC1.

Autoimmune and autoinflammatory mechanisms in uveitis

The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of T_reg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8⁺ T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders.

Diagnosis and classification of autoimmune uveitis

Uveitis is the most common ophthalmological finding in the practice of rheumatology and clinical immunology. The condition is frequently idiopathic and defined by the inflammatory status of the uvea, the part of the middle eye that includes the iris, ciliary body and choroid. Anterior uveitis involves the iris and ciliary body, while the posterior form is limited to the retina and choroid. Both forms represent indications for an urgent evaluation by an ophthalmologist as untreated cases may cause blindness. Anterior uveitis is associated with the HLA-B27 allele and is a classification criterion for seronegative arthritis forms such as ankylosing spondylitis, psoriatic arthropathy, arthritis associated with Crohn's disease and ulcerative colitis, and reactive arthritis. Posterior uveitis is associated with Behcet's disease and HLA-B51. The clinical suspicion is raised by self-reported symptoms in the case of anterior involvement and floaters for posterior uveitis while the diagnosis, in the absence of established criteria, is made by an experienced ophthalmologist.