Neutralizing TNF-alpha activity modulates T-cell phenotype and function in experimental autoimmune uveoretinitis

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.

Transcriptome analysis of AAV-induced retinopathy models expressing human VEGF, TNF-α, and IL-6 in murine eyes

Retinopathies are multifactorial diseases with complex pathologies that eventually lead to vision loss. Animal models facilitate the understanding of the pathophysiology and identification of novel treatment options. However, each animal model reflects only specific disease aspects and understanding of the specific molecular changes in most disease models is limited. Here, we conducted transcriptome analysis of murine ocular tissue transduced with recombinant Adeno-associated viruses (AAVs) expressing either human VEGF-A, TNF-α, or IL-6. VEGF expression led to a distinct regulation of extracellular matrix (ECM)-associated genes. In contrast, both TNF-α and IL-6 led to more comparable gene expression changes in interleukin signaling, and the complement cascade, with TNF-α-induced changes being more pronounced. Furthermore, integration of single cell RNA-Sequencing data suggested an increase of endothelial cell-specific marker genes by VEGF, while TNF-α expression increased the expression T-cell markers. Both TNF-α and IL-6 expression led to an increase in macrophage markers. Finally, transcriptomic changes in AAV-VEGF treated mice largely overlapped with gene expression changes observed in the oxygen-induced retinopathy model, especially regarding ECM components and endothelial cell-specific gene expression. Altogether, our study represents a valuable investigation of gene expression changes induced by VEGF, TNF-α, and IL-6 and will aid researchers in selecting appropriate animal models for retinopathies based on their agreement with the human pathophysiology.

Tumor necrosis factor (TNF) inhibitors for juvenile idiopathic arthritis-associated uveitis

BACKGROUND

Uveitis is the most common extra-articular manifestation of juvenile idiopathic arthritis (JIA) and a potentially sight-threatening condition characterized by intraocular inflammation. Current treatment for JIA-associated uveitis (JIA-U) is largely based on physician experience, observational evidence and consensus guidelines, resulting in considerable variations in practice.  OBJECTIVES: To evaluate the effectiveness and safety of tumor necrosis factor (TNF) inhibitors used for treatment of JIA-U.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Health Sciences Literature Database (LILACS); ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We last searched the electronic databases on 3 February 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing TNF inhibitors with placebo in participants with a diagnosis of JIA and uveitis who were aged 2 to 18 years old.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology and graded the certainty of the body of evidence for seven outcomes using the GRADE classification.

MAIN RESULTS

We included three RCTs with 134 participants. One study conducted in the USA randomized participants to etanercept or placebo (N = 12). Two studies, one conducted in the UK (N = 90) and one in France (N = 32), randomized participants to adalimumab or placebo. All studies were at low risk of bias. Initial pooled estimates suggested that TNF-inhibitors may result in little to no difference on treatment success defined as 0 to trace cells on Standardization of Uveitis Nomenclature (SUN)-grading; or two-step decrease in activity based on SUN grading (estimated risk ratio (RR) 0.66; 95% confidence interval (CI) 0.21 to 2.10; 2 studies; 43 participants; low-certainty evidence) or treatment failure defined as a two-step increase in activity based on SUN grading (RR 0.31; 95% CI 0.01 to 7.15; 1 study; 31 participants; low-certainty evidence). Further analysis using the individual trial definitions of treatment response and failure suggested a positive treatment effect of TNF inhibitors; a RR of treatment success of 2.60 (95% CI 1.30 to 5.20; 3 studies; 124 participants; low-certainty evidence), and RR of treatment failure of 0.23 (95% CI 0.11 to 0.50; 3 studies; 133 participants). Almost all the evidence was on adalimumab and the evidence on etanercept was very limited.  For secondary outcomes, one study suggests that adalimumab may have little to no effect on risk of recurrence after induction of remission at three months (RR 2.50, 95% CI 0.31 to 20.45; 90 participants; very low-certainty evidence) and visual acuity, but the evidence is very uncertain; mean difference in longitudinal logMAR score change over six months was -0.01 (95% CI -0.06 to 0.03) and -0.02 (95% CI -0.07 to 0.03) using the best and worst logMAR measurement, respectively (low-certainty evidence). Low-certainty evidence from one study suggested that adalimumab treatment results in reduction of topical steroid doses at six months (hazard ratio 3.58; 95% CI 1.24 to 10.32; 74 participants who took one or more topical steroid per day at baseline). Adverse events, including injection site reactions and infections, were more common in the TNF inhibitor group. Serious adverse events were uncommon.

AUTHORS' CONCLUSIONS

Adalimumab appears to increase the likelihood of treatment success and decrease the likelihood of treatment failure when compared with placebo. The evidence was less conclusive about a positive treatment effect with etanercept. Adverse events from JIA-U trials are in keeping with the known side effect profile of TNF inhibitors. Standard validated JIA-U outcome measures are required to homogenize assessment and to allow for comparison and analysis of multiple datasets.

Pro-inflammatory cytokines in aqueous humor from dogs with anterior uveitis and post-operative ocular hypertension following phacoemulsification, primary glaucoma, and normal healthy eyes

Background

The aim of this study was to evaluate the levels of pro-inflammatory cytokines in aqueous humor (AH) from dogs with anterior uveitis and post-operative ocular hypertension (POH) following phacoemulsification, in AH from dogs with primary glaucoma, and in normal healthy eyes with no signs of anterior uveitis or other ocular diseases.

Methods

An exploratory study including 21 samples of AH collected from 15 dogs; post-phacoemulsification with anterior uveitis and POH (‘POH group’, n = 10 samples), primary glaucoma (‘glaucoma group’, n = 6 samples), and normal (‘normal group’, n = 5 samples). Target mass spectrometry via multiple reaction monitoring (MRM-MS) with the Canine Cytokine SpikeMix™ as internal standard was used to measure the pro-inflammatory cytokine levels.

Results

The MRM-MS method measured 15 pro-inflammatory cytokines. Tumor-necrosis-factor-alpha (TNFα) and interleukin-18 (IL-18) levels in AH were different between all three groups (glaucoma>POH>normal) (p = .05, p = .02, respectively). Additionally, IL-6 was higher in the ‘POH group’ compared to the ‘glaucoma group’ (p = .04) and IL-4 was higher in the ‘POH group’ compared to the ‘normal group’ (p = .04). Intraocular pressure (IOP) was positively associated with increased AH levels of IL-18 (Spearman correlation = .64, p = .03).

Conclusions

MRM-MS using the Canine Cytokine SpikeMix™ as an internal standard was established as a method to detect pro-inflammatory cytokine levels in canine AH. The study demonstrated increased levels of IL-4, IL-6, IL-18, and TNFα in AH from canines with POH following phacoemulsification. Primary glaucomatous eyes had the highest levels of IL-18 and TNFα which may indicate that inflammation plays a role in the pathogenesis of primary glaucoma in dogs.

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.

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.

TNF-α in Uveitis: From Bench to Clinic

Uveitis is an inflammation of the iris, ciliary body, vitreous, retina, or choroid, which has been shown to be the first manifestation of numerous systemic diseases. Studies about the immunopathogenesis and treatment of uveitis are helpful to comprehend systemic autoimmune diseases, and delay the progression of systemic autoimmune diseases, respectively. Tumor necrosis factor-alpha (TNF-α), a pleiotropic cytokine, plays a pivotal role in intraocular inflammation based on experimental and clinical data. Evidence of the feasibility of using anti-TNF-α agents for uveitis management has increased. Although there are numerous studies on TNF-α in various autoimmune diseases, the pathological mechanism and research progress of TNF-α in uveitis have not been reviewed. Therefore, the objective of this review is to provide a background on the role of TNF-α in the immunopathogenesis of uveitis, as well as from bench to clinical research progress, to better guide TNF-α-based therapeutics for uveitis.

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.

A review of ocular adverse events of biological anti-TNF drugs

The recent introduction of biological agents has revolutionized the treatment of chronic immune-inflammatory diseases; however, this new therapy did not come without significant side effects.Through large controlled studies indicating decrease in the number of uveitis flares, the role of TNF inhibitors therapy for non-infectious uveitis gained more ground. Paradoxically to its therapeutic effect, there are reports associating these drugs with the onset or recurrence of inflammatory eye disease.A number of studies have suggested possible roles for anti-TNF-α agents in precipitating or worsening an underlying inflammatory process, including the hypothesis of a disequilibrium in cytokine balance, but to date the mechanisms responsible for these adverse events are not fully understood.A PubMed literature search was performed using the following terms: ophthalmic complication, uveitis, inflammatory eye disease, optic neuritis, neuropathy, adverse events, anti-TNF, TNF alpha inhibitor, infliximab, etanercept, adalimumab, golimumab, certolizumab, and biologics. The data presented in this study was mainly derived from the use of TNF inhibitors in rheumatology, essentially because these drugs have been used for a longer period in this medical field.Many of the ocular adverse events reported on this review may be considered a paradoxical effect of anti-TNF therapy. We found a variety of data associating new onset of uveitis with anti-TNF therapy for rheumatic conditions, predominantly under etanercept.In conclusion, although there is increasing data on ocular adverse events, it remains to be seen whether the suggested link between TNF inhibitors and the onset of ocular inflammation is substantiated by more quality data. Nevertheless, the awareness of potential treatment side effects with anti-TNF should be highlighted.

Regulatory T cells and IL-17A levels in noninfectious uveitis

PURPOSE

Regulatory T cells (Tregs) have been intensively studied in a myriad of autoimmune diseases. As for noninfectious uveitis (NIU), results have been contradictory, and studies have failed to demonstrate a consistent reduction in Treg cell frequency in patients with active disease. The present study aims to characterize T lymphocyte subsets, including naïve and memory Tregs as well as their respective CD39 expression, in the peripheral blood of NIU patients. Inflammatory as well as suppressive cytokine profiles were also evaluated.

METHODS

T cell subpopulations were evaluated by multiparametric flow cytometry using anti-CD3, anti-CD4, anti-CD45, anti-CD45RA, anti-CD197, anti-CD25, anti-CD127, and anti-CD39. Treg cells were defined as CD3 + CD4⁺CD25^hiCD127^low. A multiplex bead-based immunoassay was used to determine TNF-α, IFN-ɣ, IL-17A, IL-10, and TGF-β levels.

RESULTS

Twenty-nine patients with active NIU were included as well as 15 sex- and age-matched controls. There were no significant differences in T lymphocyte subsets, including Tregs, between patients and controls. However, patients with a lower grade of anterior chamber or vitreous inflammatory cellular reaction showed higher memory Treg counts than controls, with no respective increase in CD39+ expression, and a tendency for higher IL-17A levels (p = 0.06). This IL-17A elevation was present in the total NIU group (p = 0.08) as well as a positive correlation between IL-17A levels and the absolute counts of memory Tregs (p = 0.013; R = 0.465). Patients with higher IL-17A levels also showed higher serum concentrations of memory (p = 0.001) and naïve (p = 0.003) Tregs as well as elevated TNF-α (p < 0.0001) and IFN-ɣ (p = 0.016) levels. Negative correlations were observed between IL-10 and TGF-β levels and the percentages of memory (p = 0.030; R = - 0.411) and total CD39+ Tregs (p = 0.051; R = - 0.373) in the peripheral blood of NIU patients.

CONCLUSION

Our results showed that total Treg levels were not reduced in patients with NIU. Further characterization of Treg subsets, including memory Tregs and respective CD39 expression, may provide additional insight on the role of Treg cells in NIU. Consistent high levels of circulating IL-17A in NIU patients are in accordance with previous studies and reinforce this cytokine's vital role in uveitis pathogenesis and its possible use as a therapeutic target.

Uveitis Therapy With Shark Variable Novel Antigen Receptor Domains Targeting Tumor Necrosis Factor Alpha or Inducible T-Cell Costimulatory Ligand

PURPOSE

We assess the efficacy of two next-generation biologic therapies in treating experimental autoimmune uveitis.

METHODS

Variable binding domains from shark immunoglobulin novel antigen receptors (VNARs) were fused with a mouse IgG2a constant domain (Fc) to generate VNAR-Fc molecules with binding specificity to tumor necrosis factor alpha (TNFα) or inducible T-cell costimulatory ligand (ICOSL). Treatment with VNAR-Fc fusion proteins was compared to treatment with dexamethasone or vehicle in the Lewis rat model of experimental autoimmune uveitis (EAU). Inflammation control was determined by comparing OCT clinical and histologic scores, and aqueous humor protein concentration. The concentration of 27 inflammatory cytokines in the aqueous humor was measured using a multiplex enzyme-linked immunosorbent assay platform.

RESULTS

Administration of S17-Fc significantly decreased clinical, histologic, and aqueous protein levels when compared to vehicle treatment. Inflammation scores and aqueous protein levels in A5-Fc-treated animals were decreased compared to vehicle treatment, but not significantly. The concentration of vascular endothelial growth factor (VEGF), regulated on activation, normal T cell expressed and secreted (RANTES), macrophage inflammatory protein 1 alpha (MIP-1α), interleukin (IL)-1β, LPS-induced CXC chemokine (LIX), monocyte chemoattractant protein-1 (MCP-1), and interferon (IFN)-γ were significantly decreased in the eyes of animals treated with dexamethasone. VNAR treatment demonstrated a trend towards decreased cytokine concentrations, but only VEGF and RANTES were significantly decreased by S17-Fc.

CONCLUSIONS

Treatment with the anti-TNFα VNAR S17-Fc ameliorates EAU as effectively as treatment with corticosteroids.

TRANSLATIONAL RELEVANCE

VNAR-Fc molecules are a next-generation therapeutic biologic that overcome the limitations of classical biologic monoclonal antibodies, such as complex structure, large size, and limited tissue penetration. This is a novel drug modality that could result in the development of new therapy options for patients with noninfectious uveitis.

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.

Non-viral ocular gene therapy, pEYS606, for the treatment of non-infectious uveitis: Preclinical evaluation of the medicinal product

Non-infectious uveitis (NIU) is the first cause of blindness that can be cured if optimal anti-inflammatory therapy can be achieved. Systemic anti-TNF (Tumor Necrosis Factor) agents have been recently approved for NIU but no local delivery of anti-TNF is available. For sustained production of secreted therapeutic proteins into the eye, non-viral gene therapy using plasmid electrotransfer in the ciliary muscle has been proposed. In this paper, we report the development steps of pEYS606, a clinical-grade plasmid DNA, devoid of antiobiotic selection gene, encoding a fusion protein consisting of the extracellular domain of the soluble p55 TNF-α receptor linked to the human IgG1 Fc domain (hTNFR-Is/hIgG1 or Protein 6), with high affinity for human TNF-α, for non-viral gene transfer into the ocular ciliary muscle. Electrotransfer of pEYS606 in the ciliary muscle significantly reduced ocular inflammation in two well-established rat models of uveitis, the endotoxin-induced uveitis (EIU) and the experimental autoimmune uveitis (EAU). In addition, in EAU, a significant protection of photoreceptors was demonstrated after pEYS606 treatment. The improved pharmacokinetic profile of intraocularly-secreted protein as compared to direct intravitreous injection of recombinant protein allowed to demonstrate Protein 6 efficacy at very low concentrations. Based on these results, a phase I/II clinical trial is conducted [ClinicalTrials.gov Identifier: NCT03308045].

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.

Doyne lecture 2016: intraocular health and the many faces of inflammation

Dogma for reasons of immune privilege including sequestration (sic) of ocular antigen, lack of lymphatic and immune competent cells in the vital tissues of the eye has long evaporated. Maintaining tissue and cellular health to preserve vision requires active immune responses to prevent damage and respond to danger. A priori the eye must contain immune competent cells, undergo immune surveillance to ensure homoeostasis as well as an ability to promote inflammation. By interrogating immune responses in non-infectious uveitis and compare with age-related macular degeneration (AMD), new concepts of intraocular immune health emerge. The role of macrophage polarisation in the two disorders is a tractable start. TNF-alpha regulation of macrophage responses in uveitis has a pivotal role, supported via experimental evidence and validated by recent trial data. Contrast this with the slow, insidious degeneration in atrophic AMD or in neovasular AMD, with the compelling genetic association with innate immunity and complement, highlights an ability to attenuate pathogenic immune responses and despite known inflammasome activation. Yolk sac-derived microglia maintains tissue immune health. The result of immune cell activation is environmentally dependent, for example, on retinal cell bioenergetics status, autophagy and oxidative stress, and alterations that skew interaction between macrophages and retinal pigment epithelium (RPE). For example, dead RPE eliciting macrophage VEGF secretion but exogenous IL-4 liberates an anti-angiogenic macrophage sFLT-1 response. Impaired autophagy or oxidative stress drives inflammasome activation, increases cytotoxicity, and accentuation of neovascular responses, yet exogenous inflammasome-derived cytokines, such as IL-18 and IL-33, attenuate responses.

Anti-tumor necrosis factor-α therapy in uveitis

Since the first reported use in 2001 of an anti-tumor necrosis factor-alpha (TNF-α) agent, infliximab, for the treatment of uveitis, several new anti-TNF-α agents have emerged for the treatment of refractory noninfectious uveitides, although their use remains off-label in the US. These agents have demonstrated remarkable clinical antiinflammatory efficacy and a potential immunoregulatory role in selected uveitis patients, but it is currently unclear whether they can modify the natural history of disease. We review the rationale and clinical indications for this therapy, the differences between agents, how to manage dosing and intervals, and how to screen for and identify potential side effects. We also present a summary of the science behind the use of anti-TNF-α agents in ocular inflammation and the evidence for their efficacy.

Regulatory T cell levels and cytokine production in active non-infectious uveitis: in-vitro effects of pharmacological treatment

The aim of this study was to quantify the proportion of regulatory T cells (Treg ) and cytokine expression by peripheral blood mononuclear cells (PBMCs) in patients with active non-infectious uveitis, and to evaluate the effect of in-vitro treatment with infliximab, dexamethasone and cyclosporin A on Treg levels and cytokine production in PBMCs from uveitis patients and healthy subjects. We included a group of 21 patients with active non-infectious uveitis and 18 age-matched healthy subjects. The proportion of forkhead box protein 3 (FoxP3)(+) Treg cells and intracellular tumour necrosis factor (TNF)-α expression in CD4(+) T cells was determined by flow cytometry. PBMCs were also either rested or activated with anti-CD3/anti-CD28 and cultured in the presence or absence of dexamethasone, cyclosporin A and infliximab. Supernatants of cultured PBMCs were collected and TNF-α, interleukin (IL)-10, IL-17 and interferon (IFN)-γ levels were measured by enzyme-linked immunosorbent assay (ELISA). No significant differences were observed in nTreg levels between uveitis patients and healthy subjects. However, PBMCs from uveitis patients produced significantly higher amounts of TNF-α and lower amounts of IL-10. Dexamethasone treatment in vitro significantly reduced FoxP3(+) Treg levels in PBMCs from both healthy subjects and uveitis patients, and all tested drugs significantly reduced TNF-α production in PBMCs. Dexamethasone and cyclosporin A significantly reduced IL-17 and IFN-γ production in PBMCs and dexamethasone up-regulated IL-10 production in activated PBMCs from healthy subjects. Our results suggest that PBMCs from patients with uveitis express more TNF-α and less IL-10 than healthy subjects, and this is independent of FoxP3(+) Treg levels. Treatment with infliximab, dexamethasone and cyclosporin A in vitro modulates cytokine production, but does not increase the proportion of FoxP3(+) Treg cells.

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.

Birdshot uveitis: current and emerging treatment options

Birdshot chorioretinopathy is a relatively uncommon subtype of idiopathic posterior uveitis with distinct clinical characteristics and a strong genetic association with the Human Leukocyte Antigen (HLA)-A29 allele. The diagnosis remains clinical and is based on the presence of typical clinical features, including multiple, distinctive, hypopigmented choroidal lesions throughout the fundus. The long-term visual prognosis of this disorder, however, remains guarded – central visual acuity can be preserved until late in the disease and it is not uncommon for patients to receive inadequate immunosuppressive treatment, leading to a poor long-term outcome in which peripheral retinal damage eventually leads to visual deterioration. Birdshot chorioretinopathy has proven a particularly attractive area of study within the field of uveitis, as it is a relatively easily defined disease with an associated human leukocyte antigen haplotype. Despite this, however, the immune mechanisms involved in its pathogenesis remain unclear, and some patients continue to lose retinal function despite therapy with corticosteroids and conventional immunosuppressive agents. Laboratory research continues to investigate the underlying mechanisms of disease, and clinical research is now being driven to improve the phenotyping and monitoring of this condition as, in the era of so-called personalized medicine, it is becoming increasingly important to identify patients at risk of visual loss early so that they can be treated more aggressively with targeted therapies such as the newer biological agents. This approach requires the formation of collaborative groups, as the relative rarity of the condition makes it difficult for one center to accumulate enough patients for worthwhile studies. Nevertheless, results obtained with newer therapies, such as biological agents directed against particular cytokines or cell-surface receptors, demonstrate ever improving control of the inflammation in refractory cases, providing hope that the outlook for visual function in this condition can only improve.

Systemic therapies for inflammatory eye disease: past, present and future

In this review we consider the current evidence base for treatments in inflammatory eye disease, and in particular uveitis, from a historical perspective. We consider the challenges that have traditionally hindered progress in inflammatory eye disease including small target populations, heterogeneous disease groups, poorly defined phenotypes, diagnostic inconsistency, subjective outcome measures, specific issues around visual acuity as an outcome measure and low commercial interest. Strategies to address these issues are considered de novo and with reference to recent advances outside of ophthalmology and highlight the promise for ocular inflammation. Progress in these specialties has included the development of thriving clinical-trial cultures, public-private partnerships, pathogenetic- and structure-led drug design, efficient drug development pipelines, and biomarker-defined treatment protocols enabling personalization of medicine. Although there are challenges, these are exciting opportunities as we seek to develop safe and effective treatments for patients with inflammatory eye disease.

Biologic agents in experimental autoimmune uveitis

Experimental uveitis models were developed in an effort to elucidate the pathogenesis of human uveitis. The therapeutic effects of numerous anti-inflammatory agents including corticosteroids and immunomodulatory agents including biologic response modifiers have been investigated in both experimental and human uveitis. Monoclonal antibodies to tumor necrosis factor alpha and anti-interleukins, among others, demonstrate efficacy and are employed in the treatment of uveitis refractory to conventional immunomodulatory agents.

Epigenetics, autoimmunity and hematologic malignancies: a comprehensive review

The relationships between immunological dysfunction, loss of tolerance and hematologic malignancies have been a focus of attention in attempts to understand the appearance of a higher degree of autoimmune disease and lymphoma in children with congenital immunodeficiency. Although multiple hypotheses have been offered, it is clear that stochastic processes play an important role in the immunopathology of these issues. In particular, accumulating evidence is defining a role of epigenetic mechanisms as being critical in this continuous spectrum between autoimmunity and lymphoma. In this review, we focus attention predominantly on the relationships between T helper 17 (Th17) and T regulatory populations that alter local microenvironments and ultimately the expression or transcription factors involved in cell activation and differentiation. Abnormal expression in any of the molecules involved in Th17 and/or Treg development alter immune homeostasis and in genetically susceptible hosts may lead to the appearance of autoimmunity and/or lymphoma. These observations have clinical significance in explaining the discordance of autoimmunity in identical twins. They are also particularly important in the relationships between primary immune deficiency syndromes, immune dysregulation and an increased risk of lymphoma. Indeed, defining the factors that determine epigenetic alterations and their relationships to immune homeostasis will be a challenge greater or even equal to the human genome project.

Minimal-change disease secondary to etanercept

Etanercept is a soluble tumor necrosis factor alpha (TNFα) receptor which is widely used in the treatment of rheumatoid arthritis, psoriasis and other autoimmune inflammatory disorders. It is known for its relative lack of nephrotoxicity; however, there are reports on the development of nephrotic syndrome associated with the treatment with TNFα antagonists. Here, we describe a patient with psoriasis who developed biopsy-proven minimal-change disease (MCD) shortly after initiating etanercept. Our case is unique in that the MCD resolved after discontinuation of this medication, notably without the use of corticosteroids, strongly suggesting a drug-related phenomenon.

Role of adalimumab in the management of children and adolescents with juvenile idiopathic arthritis and other rheumatic conditions

Treatment of children and adolescents with juvenile idiopathic arthritis and other pediatric rheumatic diseases has evolved. Where once there was only a limited arsenal of medications, with significant side effects and inadequate efficacy, today, with an increased understanding of the pathogenesis of these diseases, there is a wider variety of more targeted and effective treatments. TNF-α is a cytokine involved in a number of inflammatory pathways in pediatric rheumatic diseases. The emergence of biologic modifiers that target TNF-α has been pivotal in providing the ability to deliver early and aggressive treatment. Adalimumab, a recombinant monoclonal antibody to TNF-α, is an important therapeutic option, which affords children and adolescents with chronic illnesses an improved quality of life.

Tumour necrosis factor-mediated macrophage activation in the target organ is critical for clinical manifestation of uveitis

Clinically available anti-tumour necrosis factor (TNF) biologics, which inhibit both soluble (sTNF) and transmembrane forms (tmTNF) of TNF, eliminating all TNF signalling, have successfully treated autoimmune diseases including uveitis. These have potentially serious side effects such as reactivation of latent Mycobacterium tuberculosis and, therefore, more specific inhibition of TNF signalling pathways may maintain clinical efficacy while reducing adverse effects. To determine the effects of specific pharmacological inhibition of sTNF on macrophage activation and migration, we used a mouse model of uveitis (experimental autoimmune uveoretinitis; EAU). We show that selective inhibition of sTNF is sufficient to suppress EAU by limiting inflammatory CD11b(+) macrophages and CD4(+) T cell migration into the eye. However, inhibition of both sTNF and tmTNF is required to inhibit interferon-γ-induced chemokine receptor 2, CD40, major histocompatibility complex class II and nitric oxide (NO) up-regulation, and signalling via tmTNF is sufficient to mediate tissue damage. In confirmation, intravitreal inhibition of sTNF alone did not suppress disease, and inflammatory cells that migrated into the eye were activated, generating NO, thus causing structural damage to the retina. In contrast, intravitreal inhibition of both sTNF and tmTNF suppressed macrophage activation and therefore disease. We conclude that sTNF is required for inflammatory cell infiltration into target tissue, but at the tissue site inhibition of both sTNF and tmTNF is required to inhibit macrophage activation and to protect from tissue damage.

Interplay between innate and adaptive immunity in the development of non-infectious uveitis

In vertebrates, the innate and adaptive immune systems have evolved seamlessly to protect the host by rapidly responding to danger signals, eliminating pathogens and creating immunological memory as well as immunological tolerance to self. The innate immune system harnesses receptors that recognize conserved pathogen patterns and alongside the more specific recognition systems and memory of adaptive immunity, their interplay is evidenced by respective roles during generation and regulation of immune responses. The hallmark of adaptive immunity which requires engagement of innate immunity is an ability to discriminate between self and non-self (and eventually between pathogen and symbiont) as well as peripheral control mechanisms maintaining immunological health and appropriate responses. Loss of control mechanisms and/or regulation of either the adaptive or the innate immune system lead to autoimmunity and autoinflammation respectively. Although autoimmune pathways have been largely studied to date in the context of development of non-infectious intraocular inflammation, the recruitment and activation of innate immunity is required for full expression of the varied phenotypes of non-infectious uveitis. Since autoimmunity and autoinflammation implicate different molecular pathways, even though some convergence occurs, increasing our understanding of their respective roles in the development of uveitis will highlight treatment targets and influence our understanding of immune mechanisms operative in other retinal diseases. Herein, we extrapolate from the basic mechanisms of activation and control of innate and adaptive immunity to how autoinflammatory and autoimmune pathways contribute to disease development in non-infectious uveitis patients.

Adalimumab specifically induces CD3(+) CD4(+) CD25(high) Foxp3(+) CD127(-) T-regulatory cells and decreases vascular endothelial growth factor plasma levels in refractory immuno-mediated uveitis: a non-randomized pilot intervention study

AIM

To explore immunoregulatory and anti-inflammatory pathways specifically targeted by a subcutaneous anti-TNFαdrug-adalimumab-which might be relevant for controlling refractory uveitis.

DESIGN

Non-randomized pilot intervention study on the effects of adalimumab on Treg populations and plasma VEGF levels in refractory uveitis patients. Inflammatory and immunological parameters were measured in 12 patients before therapy, and 1 and 6 months after therapy, and analyzed in the context of ophthalmological outcomes. The results were compared with those obtained in 10 systemic prednisone-treated uveitis patients.

RESULTS

After 1 month of treatment, all patients responded, with 67% of adalimumab group and 80% of the corticosteroid group achieving inactivity (P=0.5). Unlike steroid-treated patients, a significant increase in T-regulatory CD4(+) CD25(high) Foxp3(+) CD127(-) cells was observed in adalimumab patients after 1 month of treatment, and maintained after 6 months (P=0.003). A significant adalimumab-specific drop in plasma VEGF was observed after 1 and 6 months of treatment (P=0.019). In every single patient, Tregs but not VEGF correlated with disease activity.

CONCLUSIONS

In refractory uveitis patients treated with adalimumab, clinical efficacy may be mediated through upregulation of Tregs in addition to modulation of VEGF-mediated inflammatory pathways. These biological properties, which were not observed in patients treated with corticosteroids, may reflect the specificity of TNF-αtargeting.

Current concepts and future directions in the pathogenesis and treatment of non-infectious intraocular inflammation

The blockbuster drug paradigm is under increasing scrutiny across the biopharmaceutical industry. Intraocular inflammation poses particular challenges to this, given the heterogeneity of conditions in the uveitis spectrum, and the increasing acknowledgement of individual patient and disease variance in underlying immune responses. This need has triggered a drive towards personalised and stratified medicine, supported and enabled as a result of continued development of both experimental models and molecular biological techniques and improved clinical classification. As such we have the ability now to systematically appraise at a genomic, transcriptomic, and proteomic level individual immunophenotype, and the promise that in the eye this can be augmented by in vivo immune imaging to identify individual immunopathology. With such advances all running in parallel, we are entering an era of experimental medicine that will facilitate early diagnosis, generate biomarkers for accurate prognostication, and enable the development of individualised and targeted therapies, which can progress rapidly into clinical practice.

Biologic therapies in non-rheumatic diseases: lessons for rheumatologists?

Biologic therapies have been licensed to treat rheumatic diseases for more than a decade. In parallel, they have gained acceptance in a variety of non-rheumatic diseases, where their impact has been no less revolutionary. In this Review, we examine the application of biologics in a number of non-rheumatic autoimmune and inflammatory disorders-psoriasis, inflammatory bowel disease, uveitis, asthma, diabetes, congestive cardiac failure and multiple sclerosis. In particular, we have sought information, or lessons, that could influence their application in rheumatic diseases. For example, we highlight the potential to stratify asthma into groups that might require different targeted approaches, and focus on some of the less common adverse events associated with biologic therapies in multiple sclerosis. Similarly, we examine type 1 diabetes mellitus in the context of potential therapeutic induction of immune tolerance. Working collaboratively, across specialties, there is significant synergy to be gained in regard to understanding how biologic therapies work, how best to use them, and the adverse effects we should be conscious of.

Cytokines in autoimmune uveitis

Autoimmune uveitis is a complex group of sight-threatening diseases that arise without a known infectious trigger. The disorder is often associated with immunological responses to retinal proteins. Experimental models of autoimmune uveitis targeting retinal proteins have led to a better understanding of the basic immunological mechanisms involved in the pathogenesis of uveitis and have provided a template for the development of novel therapies. The disease in humans is believed to be T cell-dependent, as clinical uveitis is ameliorated by T cell-targeting therapies. The roles of T helper 1 (Th1) and Th17 cells have been major topics of interest in the past decade. Studies in uveitis patients and experiments in animal models have revealed that Th1 and Th17 cells can both be pathogenic effectors, although, paradoxically, some cytokines produced by these subsets can also be protective, depending on when and where they are produced. The major proinflammatory as well as regulatory cytokines in uveitis, the therapeutic approaches, and benefits of targeting these cytokines will be discussed in this review.

Adalimumab (humira™) in ophthalmology: a review of the literature

Tumor Necrosis Factor alpha (TNF-α) is a pleiotropic cytokine which plays a primary role in the induction of inflammation in autoimmune diseases. The newest anti-TNF-α agent is adalimumab (Humira, Abbott Pharmaceutical Inc.), a human-derived antibody. This review summarizes the characteristics of adalimumab, highlighting its clinical use in systemic and ocular inflammatory disorders, and the possible therapeutic strategies. Adalimumab has been successfully used for the treatment of rheumatoid arthritis, ankylosing spondylitis, and psoriasis arthritis. More recently, adalimumab has shown promising qualities in controlling intraocular inflammations, even though this has been used prevalently as a rescue therapy for unresponsive cases. This biologic agent was also used in pediatric cases, showing a good safety and efficacy profile. Albeit no direct comparison with other biologics has been done, and adalimumab seems to be equivalent to the other anti-TNF-α, the switching to adalimumab can offer a better uveitic control. Adalimumab is a promising drug for the treatment of uveitis, even though further studies are needed on its application as a primary therapy in uveitis.

Adalimumab (Humira™): a promising monoclonal anti-tumor necrosis factor alpha in ophthalmology

Tumor necrosis factor alpha (TNF-α) is a key soluble mediator involved in the inflammatory cascade of many disorders including uveitis. Among the anti-TNF-α agents, one of the most used in immune-mediated diseases, such as inflammatory arthropathies, is adalimumab (Humira™, Abbott Pharmaceutical Inc.), a fully humanized antibody. The purpose of this review is to analyze the main pharmacological and clinical aspects of adalimumab and its efficacy both in systemic and ocular inflammatory disorders. Adalimumab was effective in treating several autoimmune diseases, such as rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. In recent years, adalimumab has been used successfully in refractory cases of intraocular inflammation. Moreover, this biological agent showed good safety and efficacy profiles in ocular use including childhood uveitis. Switching from other anti-TNF-α agents to adalimumab may offer several advantages, such as easier administration, better patient compliance, and lower rate of adverse events. Adalimumab is a promising drug for the therapy of uveitis, although further studies are needed on its application in uveitis.

Current therapeutic approaches to autoimmune chronic uveitis in children

Uveitis is an inflammatory disorder involving inflammation of the uveal tract. It is classified as anterior, intermediate, posterior or panuveitis, depending on the part of eye affected by the inflammatory process. In children, non-infectious, chronic uveitis is a relatively uncommon but serious disease, with the potential for significant long-term complications and possible blindness. Although frequently associated with an underlying systemic disease, e.g. juvenile idiopathic arthritis (JIA), a significant number of cases in children show no associated signs or symptoms, and are labelled as idiopathic. Taking into account this evidence, an anti-inflammatory therapy based on an immuno-modulatory approach seems a reasonable strategy for non-infectious chronic uveitis, in children as well as in adults. Due to a lack of controlled studies regarding uveitis in children, immunosuppressive drugs are supported only at evidence level III. The aim of this review is to report currently available medical strategies for treatment of childhood sight-threatening chronic uveitis; in addition, a step-by-step approach to the use of immunosuppressants in this context is suggested.

Clinical review: Anti-TNFalpha therapies in uveitis: perspective on 5 years of clinical experience

Despite a lack of robust evidence, anti-TNF therapies are in wide use for the treatment of noninfectious ocular inflammatory diseases. There is a clear rationale, based on mechanistic and preclinical efficacy data, for their use in posterior segment intraocular inflammation. However, their increasing use for other indications has been largely extrapolated from the benefit observed in autoinflammatory and autoimmune systemic diseases. Given their cost and the potential for significant adverse events, this review highlights the evidence for their continued use, possibilities for switching anti-TNF agents, and ways of reducing the risk of therapy.

Systemic and local anti-C5 therapy reduces the disease severity in experimental autoimmune uveoretinitis

Activation of complement occurs during autoimmune retinal and intraocular inflammatory disease as well as neuroretinal degenerative disorders. The cleavage of C5 into fragments C5a and C5b is a critical event during the complement cascade. C5a is a potent proinflammatory anaphylatoxin capable of inducing cell migration, adhesion and cytokine release, while membrane attack complex C5b-9 causes cell lysis. Therapeutic approaches to prevent complement-induced inflammation include the use of blocking monoclonal antibodies (mAb) to prevent C5 cleavage. In these current experiments, the rat anti-mouse C5 mAb (BB5.1) was utilized to investigate the effects of inhibition of C5 cleavage on disease progression and severity in experimental autoimmune uveoretinitis (EAU), a model of organ-specific autoimmunity in the eye characterized by structural retinal damage mediated by infiltrating macrophages. Systemic treatment with BB5.1 results in significantly reduced disease scores compared with control groups, while local administration results in an earlier resolution of disease. In vitro, contemporaneous C5a and interferon-gamma signalling enhanced nitric oxide production, accompanied by down-regulation of the inhibitory myeloid CD200 receptor, contributing to cell activation. These experiments demonstrate that C5 cleavage contributes to the full expression of EAU, and that selective C5 blockade via systemic and local routes of administration can suppress disease. This presents great therapeutic potential to protect against tissue damage during autoimmune responses in the retina or inflammation-induced degenerative disease.

TNFR1-dependent regulation of myeloid cell function in experimental autoimmune uveoretinitis

Experimental autoimmune uveoretinitis is an autoimmune disease induced in mice, which involves the infiltration of CD11b(+) macrophages and CD4(+) T cells into the normally immune-privileged retina. Damage is produced in the target organ following the activation of Th1 and Th17 T cells and by the release of cytotoxic mediators such as NO by activated macrophages. The majority of immune cells infiltrating into the retina are CD11b(+) myeloid cells, but, despite the presence of these APCs, relatively limited numbers of T cells are observed in the retina during the disease course. These T cells do not proliferate when leukocytes are isolated from the retina and restimulated in vitro, although they do produce both IFN-gamma and IL-17. T cell proliferation was restored by depleting the myeloid cells from the cultures and furthermore those isolated myeloid cells were able to regulate the proliferation of other T cells. The ability of macrophages to regulate proliferation depends on activation by T cell-produced IFN-gamma and autocrine TNF-alpha signaling in the myeloid cells via TNFR1. In the absence of TNFR1 signaling, relative T cell expansion in the retina is increased, indicating that regulatory myeloid cells may also act in vivo. However, TNFR1 signaling is also required for macrophages, but not T cells, to migrate into the target organ. Thus, in TNFR1 knock out mice, the amplification of autoimmunity is limited, leading to resistance to experimental autoimmune uveoretinitis induction.

Etanercept (Enbrel)-Associated Inflammatory Eye Disease: Case Report and Review of the Literature

PURPOSE

To report a case of severe anterior uveitis flare following the administration of etanercept (Enbrel) for ankylosing spondylitis and to review the literature pertaining to inflammatory eye disease associated with the use of etanercept.

METHODS

Clinical data were collected from a 52-year-old female with chronic symptomatic ankylosing spondylitis. The relationship between etanercept administration and the patient's systemic and ocular inflammation was assessed. A review of the literature was conducted to identify additional reports.

RESULTS

A patient with a history of ankylosing spondylitis exhibited acute exacerbations of uveitis that were temporally related to etanercept injections. Re-challenge was associated temporally with a worsening of symptoms, and drug withdrawal, in concert with aggressive systemic steroid treatment, resulted in rapid resolution. Seventeen cases of inflammatory eye disease (uveitis, scleritis, orbital myositis) believed to be associated with etanercept therapy were found in the recent literature.

CONCLUSIONS

Ocular inflammation is paradoxically a potential adverse event following the use of etanercept in both previously uninvolved and inflamed eyes. Careful surveillance of patients on etanercept is warranted to assure that flares in ocular inflammation are not secondary to etanercept therapy.

Adalimumab in the therapy of uveitis in childhood

PURPOSE

Chronic anterior uveitis in children often takes a serious course. Despite various immunosuppressive drugs some children do not respond sufficiently and there is a high risk of them becoming seriously disabled. Anti-TNF alpha therapy has been shown by our group and others to be mostly ineffective (Etanercept) or partly effective (Infliximab) with the risk of anaphylactic reactions. Here we report on 18 young patients treated with Adalimumab (Humira), a complete humanised anti-TNF alpha antibody.

METHODS

We retrospectively analysed 18 patients, who were treated with Adalimumab (20-40 mg, every 2 weeks, when ineffective every week); 17 had juvenile idiopathic arthritis, one was without detectable underlying disease. The age at onset of arthritis varied from 0.5-15 years and for uveitis from 2-19 years. Patients were included when the previous anti-inflammatory therapy had been ineffective. It consisted of systemic steroids (n = 18), Cyclosporin A (n = 18), Methotrexate (n = 18), Azathioprine (n = 12), Mycophenolate mofetil (n = 4), Cyclophosphamide (n = 2), Leflunomide (n = 3), Etanercept (n = 8) and Infliximab (n = 5). The grading for uveitis was: (a) effective: no relapse or more than two relapses less than before treatment, (b) mild: one relapse less than before treatment, (c) no response: no change in relapse rate and (d) worsening: more relapses under treatment than before. The grading for arthritis (depending on the clinical findings), using three out of six parameters of the ACR PED Criteria, was: effective, mild, no response, worsening.

RESULTS

For arthritis (n = 16) the response to Adalimumab was effective in 10 of 16 patients, mild in three patients, three did not respond. For uveitis (n = 18) Adalimumab was effective in 16, mild in one child, and one patient did not show any effect. After a very good response initially a shorter application time had to be used to maintain the good anti-inflammatory effect in one child. Additional immunosuppressive treatment was used in seven of the effectively treated children. Due to elevation of liver enzymes in one patient, who also took MTX, Adalimumab had to be discontinued. No anaphylactic reactions or increased frequency of infections since start of Adalimumab treatment was reported.

CONCLUSIONS

For our group of children with long lasting disease our results show that Adalimumab was effective or mildly effective against the arthritis in 81%, but in uveitis in 88%. While these results regarding arthritis are comparable with other TNF-alpha blocking drugs (Etanercept), Adalimumab seems to be much more effective against uveitis than Etanercept. Anaphylactic reactions, found in a previous study from our group after Infliximab treatment, were not seen with Adalimumab. The necessary dosage and the treatment period, which probably have to be defined individually for each patient, remain unclear.