Interleukin-22 serum levels are elevated in active scleritis

The Association of HIF-1α/rs2057482 Polymorphism with Idiopathic Scleritis in a Chinese Han Population

BACKGROUND

To investigate the association of hypoxia-inducible factor-1α (HIF-1α), Janus tyrosine kinase-signal transducer and activator of transcription (JAK-STAT) gene polymorphisms with idiopathic scleritis in a Chinese Han population.

METHODS

Ten single nucleotide polymorphisms (SNP) of HIF-1α, tyrosine kinase 2 (TYK2), signal transducer and activator of transcription 3 (STAT3), signal transducer and activator of transcription 4 (STAT4), and retinoid-related orphan nuclear receptors-γ (ROR-γ) were selected for this study. A total of 496 idiopathic scleritis patients and 1009 controls were genotyped by the MassARRAY platform and iPLEX Gold Genotyping Assay. The allele and genotype frequencies were analyzed by Chi-square test and Fisher's exact test. Stratified analyses were performed based on gender and anatomic locations of idiopathic scleritis.

RESULTS

The frequencies of CC genotype (p = 6.18 × 10-4, Pc = 0.04, OR = 0.67,95%CI = 0.53-0.84) and C allele (p = 7.08 × 10-4, Pc = 0.04, OR = 0.71,95%CI = 0.58-0.87) for HIF-1α/rs2057482 were found significantly lower in idiopathic scleritis patients when compared to healthy controls. Stratified analysis depending on gender showed significant decreased frequencies of CC genotype (CC: p = 4.04 × 10-4, Pc = 0.02, OR = 0.54, 95%CI = 0.39-0.76) and C allele (C: p = 1.62 × 10-4, Pc = 0.01, OR = 0.58, 95%CI = 0.44-0.77) in male patients. Stratification analysis of rs2057482 according to location of scleritis did not show any significant difference between three subgroups and healthy controls.

CONCLUSION

This study showed association between polymorphism of HIF-1α/rs2057482 and susceptibility to idiopathic scleritis in Han Chinese male patients.

Visual Morbidity and Outcomes of Scleritis Associated with Intraocular Inflammation Compared to Isolated Scleritis

PURPOSE

To compare visual outcomes, ocular complications and therapies for patients with scleritis-associated intraocular inflammation (SAI) and patients with isolated scleritis (IS).

RESULTS

A total of 52 patients (36 with SAI and 16 with IS) were reviewed. Mean age (standard deviation) at presentation was 48.4 years old (± 15.4) in the SAI group and 53 years old (± 17.1) in the IS group (p = .37). Visual acuity was worse at presentation and last visit for patients with SAI compared to IS (p = .04). Patients in the SAI group developed greater posterior segment complications than in the IS group (p = .002).

CONCLUSIONS

Scleritis with intraocular inflammation was associated with a higher rate of visual morbidity compared to isolated scleritis. More aggressive management strategies may be needed for patients who present with scleritis associated with inflammation.

Scleral Proteome in Noninfectious Scleritis Unravels Upregulation of Filaggrin-2 and Signs of Neovascularization

Purpose

Scleritis is a severe inflammatory ocular disorder with unknown pathogenesis. We investigated healthy sclera as well as sclera affected by noninfectious scleritis for differentially expressed proteins using a mass spectrometry approach.

Methods

We collected scleral samples of enucleated eyes due to severe noninfectious scleritis (n = 3), and control scleral tissues (n = 5), all exenterated eyes for eyelid carcinomas (n = 4), or choroidal melanoma (n = 1) without scleral invasion. Samples were prepared for the nano liquid-chromatography mass spectrometer (LC-MS), data were analyzed using proteomics software (Scaffold), and is available via ProteomeXchange (identifier PXD038727). Samples were also stained for immuno-histopathological evaluation.

Results

Mass spectrometry identified 629 proteins within the healthy and diseased scleral tissues, whereof collagen type XII, VI, and I were the most abundantly expressed protein. Collagen type II-XII was also present. Filaggrin-2, a protein that plays a crucial role in epidermal barrier function, was found upregulated in all scleritis cases. In addition, other epithelial associated proteins were upregulated (such as keratin 33b, 34, and 85, epiplakin, transglutaminase-3, galectin 7, and caspase-14) in scleritis. Further, upregulated proteins involved in regulation of the cytoskeleton (vinculin and myosin 9), and housekeeping proteins were found (elongation factor-2 and cytoplasmic dynein 1) in our study. Upregulation of filaggrin-2 and myosin-9 was confirmed with immunohistochemistry, the latter protein showing co-localization with the endothelial cell marker ETC-related gene (ERG), indicating neovascularization in scleral tissue affected by scleritis.

Conclusions

We found upregulation of filaggrin-2 and signs of neovascularization in scleral tissue of patients with noninfectious scleritis. Further research, ideally including more scleritis cases, is needed to validate our findings.

Adalimumab plus Conventional Therapy versus Conventional Therapy in Refractory Non-Infectious Scleritis

Long-term systemic glucocorticoids and non-specific immunosuppressants remain the mainstay of treatment for refractory scleritis, and result in serious side-effects and repeated inflammation flares. To assess the efficacy and safety of additional adalimumab, patients diagnosed with refractory non-infectious scleritis were enrolled. They were assigned to the conventional-therapy (CT, using systemic glucocorticoids and other immunosuppressants) group or the adalimumab-plus-conventional-therapy (ACT) group according to the treatments they received. The primary outcome was time to achieve sustained remission, assessed by a reduction in modified McCluskey's scleritis scores. Other outcomes included changes in McCluskey's scores, scleritis flares, best-corrected visual acuity, and spared glucocorticoid dosage. Patients in the ACT group achieved faster remission than those in the CT group, as the median periods before remission were 4 months vs. 2.5 months (p = 0.016). Scleritis flares occurred in 11/11 eyes in the CT group and 5/12 eyes in the ACT group (p = 0.005). Successful glucocorticoid sparing was realized in both groups, but the ACT group made it faster. No severe adverse events were observed. Data suggest that adalimumab plus conventional therapy could shorten the time to remission, reduce disease flares, and accelerate glucocorticoid withdrawal compared with conventional therapy alone.

Innate and Adaptive Gene Single Nucleotide Polymorphisms Associated With Susceptibility of Severe Inflammatory Complications in Acanthamoeba Keratitis

Purpose

Over a third of patients with Acanthamoeba keratitis (AK) experience severe inflammatory complications (SICs). This study aimed to determine if some contact lens (CL) wearers with AK were predisposed to SICs due to variations in key immune genes.

Methods

CL wearers with AK who attended Moorfields Eye Hospital were recruited prospectively between April 2013 and October 2014. SICs were defined as scleritis and/or stromal ring infiltrate. Genomic DNA was processed with an Illumina Low Input Custom Amplicon assay of 58 single nucleotide polymorphism (SNP) targets across 18 genes and tested for association in PLINK.

Results

Genomic DNA was obtained and analyzed for 105 cases of AK, 40 (38%) of whom experienced SICs. SNPs in the CXCL8 gene encoding IL-8 was significantly associated with protection from SICs (chr4: rs1126647, odds ratio [OR] = 0.3, P = 0.005, rs2227543, OR = 0.4, P = 0.007, and rs2227307, OR = 0.4, P = 0.02) after adjusting for age, sex, steroids prediagnosis, and herpes simplex keratitis (HSK) misdiagnosis. Two TLR-4 SNPs were associated with increased risk of SICs (chr9: rs4986791 and rs4986790, both OR = 6.9, P = 0.01). Th-17 associated SNPs (chr1: IL-23R rs11209026, chr2: IL-1β rs16944, and chr12: IL-22 rs1179251) were also associated with SICs.

Conclusions

The current study identifies biologically relevant genetic variants in patients with AK with SICs; IL-8 is associated with a strong neutrophil response in the cornea in AK, TLR-4 is important in early AK disease, and Th-17 genes are associated with adaptive immune responses to AK in animal models. Genetic screening of patients with AK to predict severity is viable and this would be expected to assist disease management.

Current Approach for the Diagnosis and Management of Noninfective Scleritis

ABSTRACT

Scleritis is a rare, vision-threatening inflammation of the sclera that is often associated with life-threatening systemic illnesses. Rheumatoid arthritis remains the most common associated systemic rheumatic disease and the commonest systemic association of scleritis. Granulomatosis with polyangiitis is the most common cause of vasculitis-associated scleritis. The etiopathogenesis of scleritis remains unclear, but can be immune complex-mediated or due to a local delayed hypersensitivity reaction. Scleritis can involve either the anterior or posterior sclera, and has a wide spectrum of clinical presentations. Among the subtypes of scleritis, necrotizing scleritis has an increased risk of complications and is more commonly associated with anterior uveitis and peripheral ulcerative keratitis. Posterior scleritis is often not diagnosed or missed due to its subtle clinical signs and protean manifestations. Meticulous history taking, detailed ocular examination, and a targeted array of investigations with a multi-disciplinary approach to find any underlying systemic disease are crucial for the management of a case of scleritis. Corticosteroids remain the mainstay of short-term treatment of scleritis; mild to moderate scleral inflammation may respond well to treatment with nonsteroidal antiinflammatory drug or topical corticosteroid. Corticosteroid-sparing immunosuppressive therapies are useful in cases with an inadequate response or failure to provide long-term control of inflammation, and to prevent recurrence of scleritis. Biologic agents are increasingly used in the management of scleritis, not responding to the conventional therapies. This review provides an overview of the various subtypes of scleritis and its systemic associations and evaluates current trends in the diagnosis and management of noninfective scleritis.

Systemic Regulatory T Cells and IL-6 as Prognostic Factors for Anatomical Improvement of Uveitic Macular Edema

Purpose

To investigate whether systemic immune mediators and circulating regulatory T cells (Tregs) could be prognostic factors for anatomic outcomes in macular edema secondary to non-infectious uveitis (UME).

Methods

Multicenter, prospective, observational, 12-month follow-up study of 60 patients with UME. Macular edema was defined as central subfield thickness (CST) > 300 μm measured with spectral domain optical coherence tomography (SD-OCT). Serum samples and peripheral blood mononuclear cells (PBMC) were obtained from venous blood extraction at baseline. Serum levels of IL-1β, IL-6, IL-8, IL-17, MCP-1, TNF-α, IL-10, and VEGF were determined by Luminex. Tregs population, defined as CD3+CD4+FoxP3+ in PBMC, was determined by flow cytometry. Main outcome measure was the predictive association between searched mediators and CST sustained improvement, defined as CST < 300 microns or a 20% CST decrease, at 6 months maintained until 12-months compared to baseline levels.

Results

Multivariate logistic regression analysis showed an association between CST sustained improvement at 12 months follow-up and IL-6 and Tregs baseline levels. Higher IL-6 levels were associated with less events of UME improvement (OR: 0.67, 95% CI (0.45-1.00), P = 0.042), whereas higher levels of Tregs favored such improvement (OR: 1.25, 95% CI: 1.12-2.56, P = 0.049).

Conclusions

Increased levels of Tregs and reduced levels of IL-6 in serum may be prognostic factors of sustained anatomical improvement in UME. These findings could enforce the opportunity to develop more efficient and personalized therapeutic approaches to improve long-term visual prognosis in patients with UME.

Current insights in the pathogenesis of scleritis

Scleritis is a sight-threatening inflammation characterized by severe pain and redness of the eye. It can cause blindness by severe complications like scleral and corneal necrosis, keratitis, and uveitis. The pathogenesis of scleritis is largely unknown due to a combination of the rarity of the disease, the little available human tissue-based research material, and the lack of animal models. The immune system is assumed to play a crucial role in the pathogenesis of scleritis. Multiple clues indicate probable antigenic stimuli in scleritis, and the involvement of matrix metalloproteinases in the destruction of scleral tissue. In this article we review the current insights into the pathogenesis of scleritis, and we suggest new hypotheses by implementing knowledge of systemic autoimmune disease pathogenesis. Understanding the pathogenesis of scleritis is crucial to improve the clinical management, as well as to find novel treatment modalities.

Successful Tocilizumab Treatment for Scleritis

Purpose: To present a rare case of scleritis associated with a prior diagnosis of giant cell arteritis (GCA) that was unresponsive to glucocorticoids, nonsteroidal anti-inflammatory drugs (NSAIDs), methotrexate, and azathioprine, but reached and maintained a full remission with tocilizumab.Observations: A 62-year-old Caucasian female presented with scleritis and headache. Four years earlier, the patient was diagnosed with GCA. Treatment with topical and systemic NSAIDs, prednisone and diverse disease-modifying antirheumatic drugsonly had a partial effect on the scleritis whilst the arthralgia and headaches increased. Despite the absence of laboratory evidence of active GCA, tocilizumab was started and the scleritis and headaches disappeared within several days. Prednisone could be fully tapered within 3 months and to date, 12 months after the start of tocilizumab, the patient has maintained a sustained remission.Conclusions: Our patient demonstrates that tocilizumab might represent a therapeutic option for scleritis, and its further evaluation for this severe ocular disease is worthwhile.

A cell penetrating peptide from SOCS-1 prevents ocular damage in experimental autoimmune uveitis

We describe an immunosuppressive peptide corresponding to the kinase inhibitory region (KIR) of the intracellular checkpoint protein suppressor of cytokine signaling 1 (SOCS-1) that binds to the phospho-tyrosine containing regions of the tyrosine kinases JAK2 and TYK2 and the adaptor protein MAL, and thereby inhibits signaling downstream from these signaling mediators. The peptide, SOCS1-KIR, is thus capable of downregulating overactive JAK/STAT or NF-kB signaling in somatic cells, including those in many compartments of the eye. Attachment of poly-arginine to this peptide (R9-SOCS1-KIR) allows it to penetrate the plasma membrane in aqueous media. R9-SOCS1-KIR was tested in ARPE-19 cells and was found to attenuate mediators of inflammation by blocking the inflammatory effects of IFNγ, TNFα, or IL-17A. R9-SOCS1-KIR and also protected against TNFα or IL-17A mediated damage to the barrier properties of ARPE-19 cells, as evidenced by immunostaining with the tight junction protein, zona occludin 1 (ZO-1), and measurement of transepithelial electrical resistance (TEER). Experimental autoimmune uveitis (EAU) was generated in B10. RIII mice using a peptide of interphotoreceptor retinal binding protein (IRBP^161-180) as immunogen. Topical administration of R9-SOCS1-KIR, 2 days before (prophylactic), or 7 days after immunization (therapeutic) protected ocular structure and function as seen by fundoscopy, optical coherence tomography (OCT), and electroretinography (ERG). The ability R9-SOCS1-KIR to suppress ocular inflammation and preserve barrier properties of retinal pigment epithelium makes it a potential candidate for treatment of autoimmune uveitis.

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.