Inhibitory effect of Cyclosporin A and corticosteroids on the production of IFN-γ and IL-17 by T cells in Vogt–Koyanagi–Harada syndrome

Cost-Effectiveness Analysis of Adalimumab Versus Cyclosporine for Vogt-Koyanagi-Harada Disease: A Randomized Controlled Study

PURPOSE

To compare the 26-week cost-effectiveness of adalimumab-corticosteroids (ADA-CS) and cyclosporine-corticosteroids (CSA-CS) for Vogt-Koyanagi-Harada (VKH).

METHODS

A preplanned cost-effectiveness analysis based on the per-protocol population of a randomized-controlled trial. VKH subjects were randomized to receive either cyclosporine (100-200 mg daily) combined with corticosteroids or adalimumab (40 mg twice monthly) combined with corticosteroids. The primary outcome of this cost-effectiveness study was the incremental cost-effectiveness ratio (ICER). Costs and quality-adjusted life-years (QALYs) data were calculated by the medical records and health utility, respectively. Subgroup (early and late-phase VKH) analysis and sensitivity analyses were performed.

RESULTS

The ICER at 26 weeks was $62,425/QALY for the total participants. Compared to the CSA-CS group, costs in the ADA-CS group were more expensive (mean difference [ΔA-C]: $2,497) with more gains in QALYs (mean difference [ΔA-C]: 0.04). The probability of ADA-CS being cost-effective was 0.17 and 0.41 at willingness to pay (WTP) thresholds of $12,000/QALY and $36,000/QALY, respectively. Subgroup analysis and sensitivity analyses showed consistent findings with the primary analysis.

CONCLUSIONS

Regardless of early or late-phase VKH, the CSA-CS strategy may be recommended as the preferred initial choice for the majority of VKH.

Identification of FCER1G as a cyclosporin A plus corticosteroid sensitization gene in female patients with Vogt-Koyanagi-Harada disease

The resistance development of the combination regimen of corticosteroids (CS) with cyclosporin A (CsA) leads to therapeutic failure of some patients with autoimmune diseases. In the male patients with Vogt-Koyanagi-Harada (VKH) disease, we have identified RPS4Y1 as an important resistance gene of the regimen and a functional mediator of chlorambucil (CLB). However, it remains unclear what is responsible for the resistance in female patients. In the present study, we performed RNA sequencing, tandem mass tag (TMT) proteomics, gain- and loss-of-function assays and rescue assays to screen and validate potential resistant mediators. The results showed that only Fc epsilon receptor Ig (FCER1G) exhibited significantly differential expression in CD4+ T cells among female CsA & CS resistant, sensitive and CLB & CsA & CS treated patients at transcription and protein levels. Inhibition of FCER1G was demonstrated to modulate CD4+ T cell resistance to CsA & CS in female patients. Importantly, the inhibition was mediated by elevated DNA methylation in the promoter region of the FCER1G gene. Moreover, we found that the salvage effect of CLB on CsA & CS resistance was mediated by an increased FCER1G expression via DNA demethylation in female patients. Taken together, the downregulation of FCER1G due to DNA hypermethylation is responsible for the resistance to CsA & CS and CLB reverses this resistance by inducing FCER1G expression via DNA demethylation in female patients. Modulation of FCER1G would be a promising sensitization strategy in female patients with resistance to CsA & CS.

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.

COVID-19 Vaccine-Related Vogt-Koyanagi-Harada Disease Complicated by Central Serous Chorioretinopathy during Treatment Course: Case Report and Literature Review

With the promotion of mass COVID-19 vaccination in the elimination of the SARS-CoV-2 pandemic, new side effects, including ocular complications, are emerging. In this study, we report on a 62-year-old Chinese man who developed Vogt-Koyanagi-Harada (VKH) disease six days after his third dose of an inactivated COVID-19 vaccine, with a preceding severe headache and tinnitus. His medical history included tuberculosis 20 years prior and hypertension. Systemic prednisone was administered, resulting in completely relieved inflammation and improved visual acuity. Another three and a half months later, the visual acuity of his right eye slightly decreased due to complicated central serous chorioretinopathy (CSC) disease. By gradually replacing prednisone with cyclosporine within 2 months, the subretinal fluid was completely absorbed at the last visit. Steroid-related CSC during the treatment course of VKH disease after COVID-19 vaccination has never been reported before. By reviewing relative literature, we discuss the mechanism of CSC onset in our case and the potential therapeutic strategies. Complicated CSC may develop in the eyes with vaccine-related VKH after steroid treatment. Ophthalmologists should be aware of this condition, carefully distinguish complicated CSC with inflammation relapse, and adjust the medication in a timely manner.

Indications and effects of biological agents in the treatment of noninfectious uveitis

Noninfectious uveitis is a common blinding eye disease, and an autoimmune response is involved in its pathogenesis. Biological agents have gradually been introduced into the treatment of noninfectious uveitis. The authors reviewed the clinical application and side effects of different biological agents on noninfectious uveitis. Biological agents that target TNF-α are widely used in the clinic. Other biological agents, such as IL-6- and IL-1-neutralizing antibodies, are used in patients who do not respond to TNF inhibitors. The efficacy of IL-17 neutralizing antibodies in noninfectious uveitis is controversial. Biological agents targeting T cells and signaling pathways provide new drug options for treatment of noninfectious uveitis. However, it cannot be ignored that these biological agents have side effects, such as increasing risk of infection.

Cyclosporin A up-regulated thromboxane A2 receptor through activation of MAPK and NF-κB pathways in rat mesenteric artery

Cyclosporin A (CsA) is an immunosuppressant used in transplantation patients and inflammatory diseases. CsA-induced local vasoconstriction can lead to serious side effects including nephrotoxicity and hypertension. However, the underlying mechanisms are not fully understood. Mesenteric artery rings of rats were cultured with CsA and specific inhibitors for mitogen-activating protein kinases (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. A sensitive myograph recorded thromboxane (TP) receptor-mediated vasoconstriction. Protein levels of key signaling molecules were assessed by Western blotting. The results show that CsA up-regulated the TP receptor expression with the enhanced vasoconstriction in a dose- and time-dependent manner. Furthermore, the blockage of MAPKs or NF-κB activation markedly attenuated CsA-enhanced vasoconstriction and the TP receptor protein expression. Rats subcutaneously injected with CsA for three weeks showed increased blood pressure in vivo and increased contractile responses to a TP agonist ex vivo. CsA also enhanced TP receptor, as well as p-ERK1/2, p-p38, p- IκBα, p-NF-κB P65 protein levels and decreased IκBα protein expression, demonstrating that CsA induced TP receptor enhanced-vasoconstriction via activation of MAPK and NF-κB pathways. In conclusion, CsA up-regulated the expression of TP receptors via activation of MAPK and NF-κB pathways. The results may provide novel options for prevention of CsA-associated hypertension.

Analyses of circRNA and mRNA Profiles in Vogt-Koyanagi-Harada Disease

Recent studies revealed that circular RNAs (circRNAs) are important in numerous biological process and involved in autoimmune diseases. However, their role in Vogt-Koyanagi-Harada (VKH) disease, a classical autoimmune disease, is not yet known. This research aimed to study the expression profile of mRNAs, microRNAs (miRNAs) and circRNAs and investigate the influence of circRNAs on the pathogenesis of VKH disease. We identified circRNAs, miRNAs, and mRNAs expression profiles in CD4⁺ T cells between 4 VKH patients and 3 healthy controls using the whole-transcriptome sequencing (RNA-seq) technique. We discovered that a total of 5088 mRNAs, 451 circRNAs and 433 miRNAs were differently expressed. The GO and KEGG pathway enrichment analyses were performed for significantly differentially expressed circRNAs and mRNAs. GSEA was conducted for all mRNAs. The functional enrichment suggested that the inflammatory response, the adaptive immune response, NF-kappa B signaling pathway, Th17 cell differentiation, Th1 and Th2 cell differentiation and T cell receptor signaling pathway were associated with VKH disease. In addition, based on the immune-related genes we screened, the circRNA-miRNA-mRNA ceRNA network was analyzed and constructed. Ten differently expressed mRNAs (LAT, ZAP70, ITK, ICOS, RASGRP1, PAG1, PLCG1, PRKCQ, LCK, CARD11) and 5 differently expressed circRNAs (hsa_circ_0033144, hsa_circ_0000233, hsa_circ_0000396, hsa_circ_0001924, hsa_circ_0001320) were selected to be validated by Real-time qPCR (RT-qPCR). The results of RT-qPCR turned out to be consistent with RNA-seq data. Further analysis showed that hsa_circ_0001320 and hsa_circ_0001924 may serve as crucial candidate marker genes of VKH disease. These results reveal that circRNAs may have a crucial immunomodulatory function in the pathophysiological process of VKH disease.

Vogt-Koyanagi-Harada: treatment of recurrence after administration of 3 intravenous bolus of 1 g of corticosteroids and mycophenolate mofetil

The case is presented on a young Honduran female with no medical history of note, who presented with multiple areas of exudative retinal detachment (RD), and a best-corrected visual acuity of 1.3 logMAR in both eyes. She was diagnosed with incomplete Vogt-Koyanagi-Harada syndrome, and treated early with a combination of intravenous therapy with 1 g of prednisolone per day for 3 days, as recommended by published evidence, as well as mycophenolate mofetil (2 g per day). During the corticosteroids tapering, there was a recurrence of exudative retinal detachments, and megadoses of 1 g of intravenous corticosteroids per day were reintroduced for 6 days until the complete resolution of the fluid of the exudative RD, and cyclosporine (100 mg per day), subtenon triamcinolone (40 mg/mL), and intravitreal ranibizumab once a month in the both eyes were added to the treatment, with a great control of choroidal inflammation that resulted in the remission of symptoms and signs.

miRNA Landscape in Pathogenesis and Treatment of Vogt-Koyanagi-Harada Disease

miRNAs, one of the members of the noncoding RNA family, are regulators of gene expression in inflammatory and autoimmune diseases. Changes in miRNA pool expression have been associated with differentiation of CD4⁺ T cells toward an inflammatory phenotype and with loss of self-tolerance in autoimmune diseases. Vogt–Koyanagi–Harada (VKH) disease is a chronic multisystemic pathology, affecting the uvea, inner ear, central nervous system, and skin. Several lines of evidence support an autoimmune etiology for VKH, with loss of tolerance against retinal pigmented epithelium-related self-antigens. This deleterious reaction is characterized by exacerbated inflammation, due to an aberrant T_H1 and T_H17 polarization and secretion of their proinflammatory hallmark cytokines interleukin 6 (IL-6), IL-17, interferon γ, and tumor necrosis factor α, and an impaired CD4⁺ CD25^high FoxP3⁺ regulatory T cell function. To restrain inflammation, VKH is pharmacologically treated with corticosteroids and immunosuppressive drugs as first and second line of therapy, respectively. Changes in the expression of miRNAs related to immunoregulatory pathways have been associated with VKH development, whereas some genetic variants of miRNAs have been found to be risk modifiers of VKH. Furthermore, the drugs commonly used in VKH treatment have great influence on miRNA expression, including those miRNAs associated to VKH disease. This relationship between response to therapy and miRNA regulation suggests that these small noncoding molecules might be therapeutic targets for the development of more effective and specific pharmacological therapy for VKH. In this review, we discuss the latest evidence regarding regulation and alteration of miRNA associated with VKH disease and its treatment.

Cytokines that Modulate the Differentiation of Th17 Cells in Autoimmune Uveitis

Increasing evidence has suggested that T helper 17 (Th17) cells play a central role in the pathogenesis of ocular immune disease. The association between pathogenic Th17 cells and the development of uveitis has been confirmed in experimental and clinical studies. Several cytokines affect the initiation and stabilization of the differentiation of Th17 cells. Therefore, understanding the mechanism of related cytokines in the differentiation of Th17 cells is important for exploring the pathogenesis and the potential therapeutic targets of uveitis. This article briefly describes the structures, mechanisms, and targeted drugs of cytokines-including interleukin (IL)-6, transforming growth factor-β1 (TGF-β1), IL-1β, IL-23, IL-27, IL-35, IL-2, IL-4, IL-21, and interferon (IFN)-γ-which have an important influence on the differentiation of Th17 cells and discusses their potential as therapeutic targets for treating autoimmune uveitis.

Vogt-Koyanagi-Harada patients show higher frequencies of circulating NKG2Dpos NK and NK T cells

Vogt-Koyanagi-Harada (VKH) is an autoimmune disease characterized by inflammation in tissues that contain melanocytes. We aimed to increase the knowledge regarding immunological pathways deregulated in VKH disease. We compared the percentages of circulating natural killer (NK), NK T and T cells expressing the activatory markers: CD16, CD69, NK group 2D (NKG2D), natural cytotoxicity triggering receptor 3 (Nkp30), natural cytotoxicity triggering receptor 1 (Nkp46) and the inhibitory marker: NK group 2 member A (NKG2A) in 10 active VKH patients, 20 control subjects (CTR) and seven patients with Behçet disease (BD) by flow cytometry. Cytotoxic potential of NK cells was determined through the degranulation marker CD107a expression after contact with K562 cells by flow cytometry. Moreover, plasmatic levels of 27 cytokines were determined with a multiplex bead-based assay. VKH patients showed higher percentages of NKG2D^pos NK and NK T cells versus CTR. The cytotoxic potential of NK cells induced by K562 cells was comparable between VKH patients and CTR. Finally, higher concentrations of interleukin (IL)-4, IL-5, IL-7, IL-17 and platelet-derived growth factor-subunits B (PDGF-bb) were detected in plasma of VKH patients versus CTR. The immune profile of VKH patients was similar to that of BD patients.

Vogt-Koyanagi-Harada: treatment of recurrence after administration of 3 intravenous bolus of 1g of corticosteroids and mycophenolate mofetil

The case is presented on a young Honduran female with no medical history of note, who presented with multiple areas of exudative retinal detachment (RD), and a best-corrected visual acuity of 1.3logMAR in both eyes. She was diagnosed with incomplete Vogt-Koyanagi-Harada syndrome, and treated early with a combination of intravenous therapy with 1g of prednisolone per day for 3 days, as recommended by published evidence, as well as mycophenolate mofetil (2g per day). During the corticosteroids tapering, there was a recurrence of exudative retinal detachments, and megadoses of 1g of intravenous corticosteroids per day were reintroduced for 6 days until the complete resolution of the fluid of the exudative RD, and cyclosporine (100mg per day), subtenon triamcinolone (40mg/mL), and intravitreal ranibizumab once a month in the both eyes were added to the treatment, with a great control of choroidal inflammation that resulted in the remission of symptoms and signs.

Plasma metabolomics study of Vogt-Koyanagi-Harada disease identifies potential diagnostic biomarkers

Vogt-Koyanagi-Harada (VKH) disease is a common type of uveitis in China, but the diagnosis criteria of VKH disease is controversial. The aim of this study was to investigate potential diagnostic plasma biomarkers for VKH disease. A case-control study including 55 VKH patients (28 active patients and 27 inactive VKH patients) and 30 healthy controls in a tertiary referral center was performed. The metabolic phenotype of VKH patients showed a significant difference compared to healthy controls. Fifteen differentially expressed metabolites (DEMs) were identified between active VKH patients and healthy controls and nine DEMs were found between inactive VKH patients and healthy controls after controlling variable importance in the projection (VIP) value > 1 and false discovery rate (FDR) < 0.05. D-mannose, stearic acid and L-lysine were shown to be potential diagnostic biomarkers which can discriminate active VKH patients from healthy controls with a diagnostic performance with AUC = 0.965, 0.936 and 0.910 respectively in independent diagnosis and an AUC = 0.999 when combined. Sarcosine was recognized as an independent potential biomarker which could distinguish inactive VKH patients from healthy controls. This study reveals a significant difference of plasma metabolic phenotype and identifies diagnostic biomarkers for VKH disease. Changes in the metabolic profile may provide clues towards the pathophysiology of VKH disease.

Activation of the interleukin-23/interleukin-17 signalling pathway in autoinflammatory and autoimmune uveitis

Uveitis is a group of diseases characterized by intraocular inflammation, of which some are driven by autoinflammatory or autoimmune responses, such as Vogt-Koyanagi-Harada disease, Behçet's disease, uveitis associated with spondyloarthritis, ocular sarcoidosis, sympathetic ophthalmia and birdshot chorioretinopathy. These entities have various clinical forms, but genetic and biomarker data suggest that they share a common molecular basis, activation of the Interleukin (IL)-23/IL-17 pathway. Multiple factors including genetic predisposition, various cytokine imbalances, infectious agents and gut alterations are found to trigger an aberrant response of this pathway. The enhanced activity of the IL-23/IL-17 pathway is committed to the expansion and pathogenicity of Th17 cells. Evidence from animal models demonstrates that the development of pathogenic Th17 cells is responsible for the induction of experimental autoimmune uveitis. Further findings indicate that retinal pigment epithelium (RPE) cells may be a target of IL-17. IL-17 triggers downstream inflammatory cascades and causes dysfunction of RPE cells, which may affect retinal barrier function and thereby promote intraocular inflammation. Currently, several emerging drugs blocking the IL-23/IL-17 pathway have been assessed for the treatment of uveitis in pilot studies. The purpose of this is to summarize updated biological knowledge and preliminary clinical data, providing the rationale for further development and evaluation of novel drugs targeting the IL-23/IL-17 pathway in autoinflammatory and autoimmune uveitis. Future studies may focus on translational medicine targeting the IL-23/IL-17 pathway for the improvement of diagnosis and treatment of uveitis. In conclusion, activation of the IL-23/IL-17 pathway is a critical biological event and can be an important target for the treatment of autoinflammatory and autoimmune uveitis.

Identification of Ribosomal Protein S4, Y-Linked 1 as a cyclosporin A plus corticosteroid resistance gene

Combination of corticosteroids (CS) with cyclosporin A (CsA) is widely used in the treatment of autoimmune diseases, autoinflammatory diseases and transplantation rejection. However, some patients fail to respond or develop resistance to the combination regimen. In Vogt-Koyanagi-Harada (VKH) disease model, we performed RNA sequencing (RNA-seq) based transcriptomics, isobaric tags for relative and absolute quantification (iTRAQ) based proteomics and assays in vitro to screen and validate potential resistant molecules. We found that a total of 1697 differentially expressed genes (DEGs) and 21 differentially expressed proteins (DEPs) in CD4⁺ T cells between CsA & CS-resistant and -sensitive VKH patients. Ribosomal Protein S4, Y-Linked 1 (RPS4Y1) was verified to regulate the resistance of CD4⁺ T cells from male VKH patients to CsA & CS. Importantly, we showed that chlorambucil (CLB) could reverse the resistance by RPS4Y1 suppression. Taken together, we identify RPS4Y1 as an important CsA & CS resistance gene in VKH disease. Researchers should consider validating the resistant effect of RPS4Y1 in other autoimmune diseases or organ transplantation.

Th lymphocyte subsets in patients with Vogt-Koyanagi-Harada disease

AIM

To assess helper T (Th) lymphocyte subset balance in patients with Vogt-Koyanagi-Harada (VKH) disease.

METHODS

Sixty-eight active VKH patients and seventy-two inactive VKH patients were included in this study. One hundred healthy individuals served as controls. Peripheral blood was obtained from VKH patients and healthy controls. Th lymphocyte subsets were analyzed by flow cytometry. Plasma concentration of interleukin (IL)-17, IL-10, transforming growth factor (TGF)-β, IL-23 and IL-6 was examined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

VKH patients with active uveitis had significantly higher percentages of both Th1 and Th17 cells and lower percentages of regulatory T (Treg) cells as compared with inactive VKH patients and healthy controls. Th1/Th2 and Th17/Treg ratios were also significantly elevated in active VKH patients. The percentages of Th1, Th17 and Treg cells and the Th1/Th2, Th17/Treg ratio did not differ between inactive VKH patients and healthy controls. There was no difference concerning the percentage of Th2 cells among all the groups. VKH patients with active uveitis showed an elevated level of peripheral Th17 related cytokines levels (TGF-β, IL-6, IL-23, and IL-17) and a decreased level of Treg related cytokines (IL-10) compared with inactive VKH patients and healthy controls. Inactive VKH patients showed no differences in peripheral Th17 related cytokines (TGF-β, IL-6, IL-23, and IL-17) and Treg related cytokines (IL-10) levels compared with healthy controls.

CONCLUSION

Th1 and Th17 cells are significantly increased and Treg cells significantly decreased in active VKH compared with inactive VKH or healthy controls. Therefore, Th lymphocyte subset analysis may serve as a disease biomarker for VKH.

Baicalin modulates the Treg/Teff balance to alleviate uveitis by activating the aryl hydrocarbon receptor

Autoimmune uveitis is a sight-threatening ocular inflammatory disorder. Immunological inflammation is regarded as the key to pathogenesis in autoimmune uveitis. Baicalin, the major bioactive component of Scutellaria baicalensis, possesses immunomodulatory properties. However, the role of baicalin in uveitis and its underlying mechanisms remain unclear. In the current study, we found that baicalin treatment obviously inhibited the intraocular inflammatory process in mice with experimental autoimmune uveitis, along with clear declines in infiltrated inflammatory cells and inflammatory cytokine transcription in the retina and draining lymph nodes. Furthermore, baicalin treatment increased the frequency and number of regulatory T cells and decreased the frequency and number of effector T cells (Th1 and Th17 cells) in the draining lymph nodes of mice with experimental autoimmune uveitis. In vitro, baicalin treatment suppressed interphotoreceptor retinoid binding protein-specific CD4+ T cell proliferation and converted CD4+ T cell differentiation. Furthermore, the expression of aryl hydrocarbon receptor was activated by baicalin treatment. Baicalin-mediated modulation of CD4+ T cell differentiation was partially abrogated by the suppression of aryl hydrocarbon receptor. These findings suggest that baicalin modulates the Treg/Teff balance and CD4+ T cell proliferation to ameliorate experimental autoimmune uveitis by activating the aryl hydrocarbon receptor.

Decreased interleukin(IL)-35 Expression is Associated with Active Intraocular Inflammation in Vogt-Koyanagi-Harada (VKH) Disease

Purpose: Recent studies have reported that IL-35 has a protective effect in autoimmune disease. In this study, we explored the role of IL-35 in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease. Methods: The IL-35/EBI3 and IL-35/P35 mRNA level was assayed by Real-Time PCR. The level of IL-35 in serum was detected by ELISA. PBMCs and monocyte-derived DCs were cultured with or without IL-35 and the concentration of IL-17, IL-10, IFN-γ, IL-6, TNF-α, and IL-1β in supernatants was tested by ELISA. Results: The serum level of IL-35 is reduced in active VKH patients. The mRNA expression of the two subunits IL-35/EBI3 and IL-35/P35 in PBMCs from patients with active VKH was also decreased. IL-35 significantly inhibited IFN-γ and IL-17 expression and induced IL-10 production by PBMCs and inhibited IL-6 production by monocyte-derived DCs. Conclusion: The current study suggests that a decreased IL-35 expression may be involved in the pathogenesis of VKH disease.

MicroRNA-20a-5p suppresses IL-17 production by targeting OSM and CCL1 in patients with Vogt-Koyanagi-Harada disease

Aim

To elucidate the role of microRNA-20a-5p (miR-20a-5p) in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease.

Methods

Quantitative real-time PCR was used to quantify miR-20a-5p expression in CD4+ T cells from patients with active VKH and normal controls. The promoter methylation status of miR-20a-5p was detected by bisulfite sequencing PCR. Targets were evaluated by a luciferase reporter assay. The functional effects of miR-20a-5p on CD4+ T cells from patients with active VKH were assessed by upregulation or downregulation of its expression using liposomes.

Results

The miR-20a-5p level was significantly decreased in CD4+ T cells from patients with active VKH as compared with normal controls. The two genes, oncostatin M (OSM) and C-C motif chemokine ligand 1 (CCL1), were identified as targets of miR-20a-5p. The upregulation of miR-20a-5p significantly suppressed interleukin 17 (IL-17) production in CD4+ T cells from patients with active VKH, whereas downregulation of miR-20a-5p exhibited an inverse effect. In addition, overexpression of OSM and CCL1 could rescue the effect of the upregulation of miR-20a-5p. Moreover, the level of miR-20a-5p was reduced in response to hypermethylation of the promoter. Further study showed that miR-20a-5p suppressed the activity of the phosphoinositide 3-kinase-AKT pathway.

Conclusions

Our findings indicate that downregulation of miR-20a-5p is caused by promoter hypermethylation. MiR-20a-5p could also suppress the production of IL-17 by targeting OSM and CCL1 production in CD4+ T cells in patients with active VKH.

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.

Hypermethylation of Interferon Regulatory Factor 8 (IRF8) Confers Risk to Vogt-Koyanagi-Harada Disease

Aberrant methylation change of IRF8 confers risk to various tumors, and abnormal expression of IRF8 is involved in many autoimmune diseases, including ocular Behcet’s disease. However, whether the methylation change of IRF8 is associated with Vogt-Koyanagi-Harada (VKH) disease remains unknown. In the present study, we found a decreased IRF8 mRNA expression in association with a higher methylation level in monocyte-derived dendritic cells (DCs) from active VKH patients compared with the normal and inactive subjects. DCs incubated with cyclosporin a (CsA) or dexamethasone (DEX) showed a lower methylation and higher mRNA expression of IRF8 in active VKH patients. A demethylation reagent, 5-Aza-2′-deoxycytidine (DAC) showed a notable demethylation effect as evidenced by increasing the mRNA expression and reducing the methylation level of IRF8. It also suppressed the Th1 and Th17 responses through down-regulating the expression of co-stimulatory molecules (CD86, CD80, CD40), and reducing the production of pro-inflammatory cytokines (IL-6, IL-1β, IL-23, IL-12) produced by DCs. These findings shows that hypermethylation of IRF8 in DCs confers risk to VKH disease. Demethylation of IRF8 may offer a novel therapeutic strategy protect against VKH disease.

Spectrum and visual outcomes of Vogt-Koyanagi-Harada disease in Argentina

AIM

To review all cases of Vogt-Koyanagi-Harada (VKH) disease in an Inflammatory Eye Disease Service in Argentina and to describe the clinical profile and outcomes of treatment.

METHODS

The records from patients with VKH disease between January 1980 and December 2008 were retrospectively analyzed for clinical profile, complications, and treatment. Patients were classified according to their initial treatment in group 1: high corticosteroid dose [≥1 mg/(kg·d)] within 2wk of illness onset; group 2: high corticosteroid dose, 2 to 4wk of onset and group 3: patients who received the high dose after 1mo of illness onset, patients who received lower oral doses than 1 mg/(kg·d) without regarding the time of beginning of the disease.

RESULTS

A total of 210 eyes of 105 patients were included. The mean age at presentation was 32.6±13y (range: 10-74y), and 86.7% were female. The mean duration of follow up was 144±96.6mo. Patients in the group 1 had significantly higher visual acuity than the other groups (P<0.0001), none had (loss of, or no) light perception at the end of follow up, whereas 24.7% patients in group 3 ended in light perception (P<0.004).

CONCLUSION

Patients with early high dose corticosteroid treatment have better visual acuity and fewer complications. Proper timing in referral and treatment is critical for better visual outcome in VKH disease.

Berberine exerts an anti-inflammatory role in ocular Behcet's disease

Behcet's disease is a multi-system inflammatory disorder, and ocular Behcet's disease (OBD) is one of the most common causes of uveitis in China. A number of studies have indicated that Th17 cells, a subset of interleukin-17 (IL-17)-producing CD4⁺ T-helper cells, serve important roles in the pathogenesis of OBD. Berberine (BBR) is an isoquinoline derivative alkaloid isolated from Chinese herbs, and has been used traditionally for the treatment of gastrointestinal disorders. The aim of the present study was to investigate the effect of BBR on Th17 cell proliferation and cytokine secretion, and the expression and activation of the signal transducer and activator of transcription 3 (STAT3) transcription factor in OBD in vitro. Blood samples were obtained from healthy controls and patients with active ocular Behcet's disease. Peripheral blood mononuclear cells (PBMCs) or CD4⁺ T cells were cultured for three days with or without BBR and in the presence of anti-CD3 and anti-CD28 antibodies. IL-17 expression in cell sample supernatants was determined by enzyme-linked immunosorbent assay, and cell viability was measured using the Cell Counting kit-8 assay. The number of CD4⁺IL-17⁺ cells and the expression level of phosphorylated (p)-STAT3 in CD4⁺ T cells was determined using flow cytometry analysis. The expression of IL-17 was increased in patients with active OBD following the activation of PBMCs and CD4⁺ T cells with anti-CD3 and anti-CD28 antibodies when compared with healthy controls. However, no significant difference in cell viability following exposure to BBR was observed in PBMCs derived from healthy controls or patients with OBD. Following incubation with BBR, the expression of IL-17 was reduced and the number of CD4⁺IL-17⁺ cells was decreased in patients with active OBD and healthy controls. Furthermore, the expression of p-STAT3 was significantly decreased in the presence of BBR in healthy controls. In conclusion, the results of the present study demonstrate that BBR may suppress the Th17 response in patients with OBD by reducing STAT3 phosphorylation. BBR may be a potential therapeutic agent for the treatment of OBD.

Vogt-Koyanagi-Harada disease: Novel insights into pathophysiology, diagnosis and treatment

Vogt-Koyanagi-Harada (VKH) disease is one of the major vision-threatening diseases in certain populations, such as Asians, native Americans, Hispanics and Middle Easterners. It is characterized by bilateral uveitis that is frequently associated with neurological (meningeal), auditory, and integumentary manifestations. Although the etiology and pathogenesis of VKH disease need to be further elucidated, it is widely accepted that the clinical manifestations are caused by an autoimmune response directed against melanin associated antigens in the target organs, i.e. the eye, inner ear, meninges and skin. In the past decades, accumulating evidence has shown that genetic factors, including VKH disease specific risk factors (HLA-DR4) and general risk factors for immune mediated diseases (IL-23R), dysfunction of immune responses, including the innate and adaptive immune system and environmental triggering factors are all involved in the development of VKH disease. Clinically, the criteria of diagnosis for VKH disease have been further improved by the employment of novel imaging techniques for the eye. For the treatment, early and adequate corticosteroids are still the mainstream regime for the disease. However, immunosuppressive and biological agents have shown benefit for the treatment of VKH disease, especially for those patients not responding to corticosteroids. This review is focused on our current knowledge of VKH disease, especially for the diagnosis, pathogenesis (genetic factors and immune mechanisms), ancillary tests and treatment. A better understanding of the role of microbiome composition, genetic basis and ongoing immune processes along with the development of novel biomarkers and objective quantitative assays to monitor intraocular inflammation are needed to improve current management of VKH patients.

Decreased B and T lymphocyte attenuator in Behcet's disease may trigger abnormal Th17 and Th1 immune responses

Behcet's disease (BD) is a chronic, systemic and recurrent inflammatory disease associated with hyperactive Th17 and Th1 immune responses. Recent studies have shown that B and T lymphocyte attenuator (BTLA) negatively regulates the immune response. In this study, we investigated whether BTLA activation could be exploited to inhibit the development of abnormal immune responses in BD patients. BTLA expression in PBMCs and CD4(+) T cells was significantly decreased in active BD patients. Decreased BTLA level was associated with increased Th17 and Th1 responses. Activation of BTLA inhibited the abnormal Th17 and Th1 responses and IL-22 expression in both patients and controls. Addition of an agonistic anti-BTLA antibody remarkably inhibited DC-induced Th17 and Th1 cell responses, resulted in decreased production of the Th17 and Th1-related cytokines IL-1beta, IL-6, IL-23 and IL-12p70 and reduced CD40 expression in DCs. In conclusion, decreased BTLA expression in ocular BD may lead to inappropriate control of the Th17 and Th1 immune responses and DC functions. Therefore, BTLA may be involved in the development and recurrence of this disease. Agonistic agents of BTLA may represent a potential therapeutic approach for the treatment of BD and other inflammatory diseases mediated by abnormal Th17 and Th1 immune responses.

The Role of IL-17 and Th17 Lymphocytes in Autoimmune Diseases

The end of twentieth century has introduced some changes into T helper (Th) cells division. The identification of the new subpopulation of T helper cells producing IL-17 modified model of Th1-Th2 paradigm and it was named Th17. High abilities to stimulate acute and chronic inflammation made these cells ideal candidate for crucial player in development of autoimmune disorders. Numerous publications based on animal and human models confirmed their pivotal role in pathogenesis of human systemic and organ-specific autoimmune diseases. These findings made Th17 cells and pathways regulating their development and function a good target for therapy. Therapies based on inhibition of Th17-dependent pathways are associated with clinical benefits, but on the other hand are frequently inducing adverse effects. In this review, we attempt to summarize researches focused on the importance of Th17 cells in development of human autoimmune diseases as well as effectiveness of targeting IL-17 and its pathways in pre-clinical and clinical studies.

Incidence and clinical features of recurrent Vogt-Koyanagi-Harada disease in Japanese individuals

PURPOSE

Our aim was to determine the recurrence rate of inflammation in Vogt-Koyanagi-Harada (VKH) disease and to describe its clinical features.

METHODS

We retrospectively evaluated patients diagnosed as having VKH disease with exudative retinal detachment at the Osaka University Hospital or the Japanese Community Healthcare Organization, Osaka Hospital, between 1998 and 2012. All patients received high-dose corticosteroid therapy as the initial treatment and were followed for at least 6 months. Demographic data, including age, sex, visual acuity (VA) levels at initial presentation and at 1 year after initial therapy, treatment received, and recurrent episodes were reviewed.

RESULTS

Fifty-five consecutive patients with VKH disease were identified (36 women; mean age 38.6 ± 10.4 years). Fourteen patients (25.5 %) had recurrent inflammation, which manifested as posterior uveitis in eight and as anterior uveitis in six of the patients. Recurrent posterior segment inflammation was more likely to develop in patients whose VA at initial presentation was poor (P = 0.039) and in whom orally administered corticosteroid was tapered rapidly (to 30 mg within 3 weeks or less, to 20 mg within 2 months or less, and to 10 mg within 3 months or less) (P = 0.006, P = 0.066, and P = 0.041, respectively).

CONCLUSIONS

About 25 % of patients with VKH disease had recurrent inflammation. Poor initial VA and rapid tapering of the corticosteroid were associated with posterior recurrence.

Discrepant expression of cytokines in inflammation- and age-related cataract patients

PURPOSE

Inflammatory cataracts secondary to Behcet's disease (BD) or Vogt-Koyanagi-Harada disease (VKH) are thought to result from a pathological dysregulation of cytokines that is different from that of age-related (AR) cataracts. However, little is known about the function of cytokines in the development of inflammatory cataracts. The purpose of this study was to identify possible differences in cytokine expression in inflammation- and age-related cataract patients.

METHODS

Analysis techniques involving the concomitant use of a cocktail of antibody-coated non-magnetic beads were used to determine the cytokine expression profiles of BD, VKH and AR cataract patients. Furthermore, anterior chamber aqueous flares and inflammatory cells were quantitatively measured with a laser flare cell meter (LFCM).

RESULTS

The expressions of interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-17A, and interferon-γ (IFN-γ) were analyzed in aqueous humor (AqH), phytohemagglutinin (PHA)-stimulated and non-PHA-stimulated cultures of peripheral blood mononuclear cells (PBMCs) from the three types of cataract patients. IL-6 and IFN-γ were identified above the detection limits, but, among the BD and VKH cataract patients, only the levels of IL-6 were significantly higher in both the AqH and PBMC non-PHA cultures compared with the levels observed in the AR cataract patients. In contrast, IFN-γ was significantly elevated in the AqH of the BD cataract patients compared with the VKH and AR cataract patients. In the PHA-stimulated PBMC cultures, IL-2, IFN-γ, IL-6, and IL-17A were significantly increased, and the IL-6 level was significantly higher in the VKH patients than in the BD and AR cataract patients. The correlation analyses of the cytokines and inflammation indexes of the AqH obtained with the LFCM revealed that only IL-6 was significantly correlated with the inflammation index.

CONCLUSION

Distinct expression profiles of cytokines and the correlations of these profiles with in vivo inflammatory indexes for inflammatory and AR cataract patients were identified.

Decreased expression of the aryl hydrocarbon receptor in ocular Behcet's disease

Recent studies show that the aryl hydrocarbon receptor (AhR) is involved in immune responses. AhR is activated following interaction with its ligands, such as 6-formylindolo[3,2-b]carbazole (FICZ) and 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE). In this study, we investigated the role of AhR activation by its endogenous ligands in the pathogenesis of ocular Behcet's disease (BD). The expression of AhR was significantly decreased in active BD patients as compared to inactive BD patients and normal controls. Both FICZ and ITE inhibited Th1 and Th17 polarization and induced the expression of IL-22 by PBMCs and by CD4⁺T cells in active BD patients and normal controls. Stimulation of purified CD4⁺T cells with FICZ or ITE caused a decreased expression of RORC, IL-17, IL-23R, and CCR6 and an increased phosphorylation of STAT3 and STAT5. The present study suggests that a decreased AhR expression is associated with disease activity in BD patients. The activation of AhR by either FICZ or ITE was able to inhibit Th1 and Th17 cell polarization. Further studies are needed to investigate whether modulation of AhR might be used in the treatment of BD.

Diagnosis and classification of Vogt-Koyanagi-Harada disease

Vogt-Koyanagi-Harada (VKH) disease is a systemic autoimmune disorder that affects pigmented tissues of the body, with its most dire manifestations affecting the eyes. This review focuses on the diagnostic criteria of VKH disease, including some information on history, epidemiology, appropriate clinical and classification criteria, etiopathogenesis, treatment and outcomes. Expert review of most relevant literature from the disease's first description to 2013 and correlation with the experience in the care of VKH disease patients at a tertiary Uveitis Service in Brazil gathered over the past 40 years. The clinical manifestations and ancillary assessment of VKH disease have been summarized in the Revised Diagnostic Criteria proposed in 2001 in a manner that allows systematic diagnosis of both acute and chronic patients. It includes the early acute uveitic manifestations (bilateral diffuse choroiditis with bullous serous retinal detachment and optic disk hyperemia), the late ocular manifestations (diffuse fundus depigmentation, nummular depigmented scars, retinal pigment epithelium clumping and/or migration, recurrent or chronic anterior uveitis), besides the extraocular manifestations (neurological/auditory and integumentary). There are two exclusion criteria, i.e. absence of previous ocular penetrating trauma or surgery and any other ocular disease that could be confounded with VKH disease. HLA-DRB1*0405 plays an important role in pathogenesis, rendering carriers more susceptible to disease. The primary ocular pathological feature is a diffuse thickening of the uveal tract in the acute phase. Later on, there may be a compromise of choriocapillaris, retinal pigment epithelium and outer retina, mostly due to an "upstream" effect, with clinical correlates as fundus derangements. Functional tests (electroretinogram and visual field testing) as well as imaging modalities (retinography, fluorescein/indocyanine green angiography, optical coherence tomography and ultrasound) play an important role in diagnosis, severity grading as well as disease monitorization. Though high-dose systemic corticosteroids remain gold-standard therapy, refractory cases may need other agents (cyclosporine A, anti-metabolites and biological agents). In spite of good visual outcomes in the majority of patients, knowledge about disease progression even after the acute phase and its impact on visual function warrant further investigation.

B cells contribute to heterogeneity of IL-17 producing cells in rheumatoid arthritis and healthy controls

Secretion of the proinflammatory cytokine Interleukin-17A (IL-17A) is the hallmark of a unique lineage of CD4 T cells designated Th17 cells, which may play a crucial role in the pathogenesis of rheumatoid arthritis (RA) and many autoimmune diseases. Recently, IL-17-producing cells other than T cells have been described, including diverse innate immune cells. Here, we show that the cellular sources of IL-17A in RA include a significant number of non-T cells. Multicolour fluorescence analysis of IL-17-expressing peripheral blood mononuclear cells (PBMC) revealed larger proportions of IL-17⁺CD3^- non-T cells in RA patients than in healthy controls (constitutive, 13.6% vs. 8.4%, and after stimulation with PMA/ionomycin 17.4% vs. 7.9% p < 0.001 in both cases). The source of IL-17 included CD3^-CD56⁺ NK cells, CD3^-CD14⁺ myeloid cells as well as the expected CD3⁺CD4⁺ Th17 cells and surprisingly a substantial number of CD3^-CD19⁺ B cells. The presence of IL-17A-expressing B cells was confirmed by specific PCR of peripheral MACS-sorted CD19⁺ B cells, as well as by the analysis of different EBV-transformed B cell lines. Here we report for the first time that in addition to Th17 cells and different innate immune cells B cells also contribute to the IL-17A found in RA patients and healthy controls.

Regulatory and effector T-cells are differentially modulated by Dexamethasone

It is assumed that the ratio between effector T cells (Teff) and regulatory T cells (Tregs) controls the immune reactivity within the T-cell compartment. The purpose of this study was to investigate if Dexamethasone (Dex) affects Teff and Tregs subsets. Dex induced on Tregs a dose and time-dependent apoptosis which resulted in a relative increase of Teff. After TCR activation, Dex induced a strong proliferative inhibition of Teff, but a weaker proliferative inhibition on Tregs. These effects were modulated by IL-2, which not only restored the proliferative response, but also prevented Dex-induced apoptosis. The highest dose of IL-2 prevented apoptosis on all FOXP3+CD4+ T cells. Meanwhile, the lowest dose only rescued activated Tregs (aTregs), probably related to their CD25 higher expression. Because Dex did not affect the suppressor capacity of aTregs either, our results support the notion that under Dex treatment, the regulatory T-cell compartment maintains its homeostasis.

Amelioration of experimental autoimmune uveitis by leflunomide in Lewis rats

Purpose

To investigate the efficacy of leflunomide in experimental autoimmune uveitis (EAU) in rats.

Methods

Lewis rats were immunized with interphotoreceptor retinoid-binding peptide (IRBP) in order to generate EAU. Rats received three dose of leflunomide through intragastric administration (prevention or treatment protocols) after immunization at three separate doses (3 mg/kg/d; 6 mg/kg/d; 12 mg/kg/d). Cyclosporin A was administered as a positive) control. Rats were euthanized during peak disease activity (day 14 or 15). Treatment effectiveness was evaluated in vivo using clinical EAU scoring (d14) and histopathological evaluation of enucleated eyes after experimental termination. The expression levels of inflammatory cytokines in the serum were quantified by ELISA. Eyeball of rats were harvested and mRNA expression of interleukin 17 (IL17) and IFN-γ were quantified through RT-PCR. Intracellular expression of interleukin (IL)-17 in the activated CD4(+) T cells was assessed by flow cytometry. The effects of leflunomide inhibition on immune responses in rats were investigated in isolated lymphocytes.

Results

Histopathological and clinical data revealed severe intraocular inflammation in the immunized rat. Inflammation reached its peak on day 14 in this EAU model. Treatment with leflunomide significantly prevented and treated EAU-induced ocular inflammation and decreased clinical and pathological scores compared to vehicle-treated eyes. Gene expression of IL17 and IFN-γwas markedly reduced in leflunomide-treated eyes. Leflunomide significantly decreased the serum levels of IL17 and IFN-γ. The study of IL17+ T cells in peripheral blood and spleen by flow cytometry showed a decreased number of Th17 cell in rats of leflunomide prevented group. Lymphocytes from animals treated with leflunomide had decreased antigen-specific proliferation in vitro compared with lymphocytes from untreated animals.

Conclusions

Oral administration of leflunomide effectively suppressed IRBP-induced uveitis in rats. These results suggest that leflunomide may be potentially clinical application in uveitis.

Enrichment of circulating interleukin-17-secreting interleukin-23 receptor-positive γ/δ T cells in patients with active ankylosing spondylitis

OBJECTIVE

Ankylosing spondylitis (AS) is a common inflammatory arthritis affecting primarily the axial skeleton. IL23R is genetically associated with AS. This study was undertaken to investigate and characterize the role of interleukin-23 (IL-23) signaling in AS pathogenesis.

METHODS

The study population consisted of patients with active AS (n = 17), patients with psoriatic arthritis (n = 8), patients with rheumatoid arthritis, (n = 9), and healthy subjects (n = 20). IL-23 receptor (IL-23R) expression in T cells was determined in each subject group, and expression levels were compared.

RESULTS

The proportion of IL-23R-expressing T cells in the periphery was 2-fold higher in AS patients than in healthy controls, specifically driven by a 3-fold increase in IL-23R-positive γ/δ T cells in AS patients. The proportions of CD4+ and CD8+ cells that were positive for IL-17 were unchanged. This increased IL-23R expression on γ/δ T cells was also associated with enhanced IL-17 secretion, with no observable IL-17 production from IL-23R-negative γ/δ T cells in AS patients. Furthermore, γ/δ T cells from AS patients were heavily skewed toward IL-17 production in response to stimulation with IL-23 and/or anti-CD3/CD28.

CONCLUSION

Recently, mouse models have shown IL-17-secreting γ/δ T cells to be pathogenic in infection and autoimmunity. Our data provide the first description of a potentially pathogenic role of these cells in a human autoimmune disease. Since IL-23 is a maturation and growth factor for IL-17-producing cells, increased IL-23R expression may regulate the function of this putative pathogenic γ/δ T cell population.

Intraocular interleukin-17 and proinflammatory cytokines in HLA-A29-associated birdshot chorioretinopathy

PURPOSE

To determine the levels of 23 immune mediators in paired aqueous humor (AqH) and serum samples from patients with birdshot chorioretinopathy (BSCR).

DESIGN

Single-centre case-control study.

METHODS

A multiplex immunoassay was used to determine the levels of 23 immune mediators (T-cell, proinflammatory, and vascular-active mediators) in paired AqH and serum of 16 BSCR patients. The AqH of 11 age-related cataract controls served as controls.

RESULTS

AqH levels of the T-cell mediators interleukin (IL)-2 (P=.044) and IL-17 (P=.039) and proinflammatory mediators IL-1β (P=.032), IL-6 (P=.034), and tumor necrosis factor α (P=.041) were elevated compared with that of age-related cataract controls. The elevated intraocular levels of IL-1β, IL-17, and tumor necrosis factor α in BSCR samples were higher than their concurrent serum levels. A significant positive correlation of intraocular mediators was noted between IL-17 and both IL-2 (r=0.744; P<.0001) and IL-23 (r=0.921; P<.0001) and between IL-2 and IL-23 (r=0.776; P<.0001). AqH levels of vascular-active mediators were not distinct between the groups.

CONCLUSIONS

BSCR patients have elevated intraocular levels of proinflammatory and T cell-associated cytokines. Our results suggest the novel pathogenic concept that BSCR is an autoimmune inflammatory disease restricted to the eye and associated with elevated IL-17.

Homeostatic control of conjunctival mucosal goblet cells by NKT-derived IL-13

Although the effects of the interleukin 13 (IL-13) on goblet cell (GC) hyperplasia have been studied in the gut and respiratory tracts, its effect on regulating conjunctival GC has not been explored. The purpose of this study was to determine the major IL-13-producing cell type and the role of IL-13 in GC homeostasis in normal murine conjunctiva. Using isolating techniques, we identified natural killer (NK)/natural killer T (NKT) cells as the main producers of IL-13. We also observed that IL-13 knockout (KO) and signal transducer and activator of transcription 6 knockout (STAT6KO) mice had a lower number of periodic acid Schiff (PAS)+GCs. We observed that desiccating stress (DS) decreases NK population, GCs, and IL-13, whereas it increases interferon-γ (IFN-γ) mRNA in conjunctiva. Cyclosporine A treatment during DS maintained the number of NK/NKT cells in the conjunctiva, increased IL-13 mRNA in NK+ cells, and decreased IFN-γ and IL-17A mRNA transcripts in NK+ and NK- populations. C57BL/6 mice chronically depleted of NK/NKT cells, as well as NKT cell-deficient RAG1KO and CD1dKO mice, had fewer filled GCs than their wild-type counterparts. NK depletion in CD1dKO mice had no further effect on the number of PAS+ cells. Taken together, these findings indicate that NKT cells are major sources of IL-13 in the conjunctival mucosa that regulates GC homeostasis.

Label-free proteomics reveals decreased expression of CD18 and AKNA in peripheral CD4+ T cells from patients with Vogt-Koyanagi-Harada syndrome

Vogt-Koyanagi-Harada (VKH) syndrome is a systemic autoimmune disease. CD4⁺ T cells have been shown to be involved in autoimmune diseases including VKH syndrome. To screen aberrantly expressed membrane proteins in CD4⁺ T cell from patients with active VKH syndrome, blood samples were taken from five patients with active VKH syndrome and five healthy individuals. A label-free quantitative proteomic strategy was used to identify the differently expressed proteins between the two groups. The results revealed that the expression of 102 peptides was significantly altered (p<0.05) between two groups and matched amino acid sequences of proteins deposited in the international protein index (ipi.HUMAN.v3.36.fasta). The identified peptides corresponded to 64 proteins, in which 30 showed more than a 1.5-fold difference between the two groups. The decreased expression of CD18 and AKNA transcription factor (AKNA), both being three-fold lower than controls in expression identified by the label-free method, was further confirmed in an additional group of five active VKH patients and six normal individuals using the Western blot technique. A significantly decreased expression of CD18 and AKNA suggests a role for both proteins in the pathogenesis of this syndrome.

Vogt-Koyanagi-Harada disease: diagnosis and treatments update

PURPOSE OF REVIEW

To review current advances in the diagnosis and therapy of Vogt-Koyanagi-Harada (VKH) disease.

RECENT FINDINGS

A new T-cell subset (Th17) may play an important role in the initiation and maintenance of inflammatory disease when stimulated by the interleukin (IL)-23, thus producing IL-17. Recent developments of new imaging techniques, such as high-resolution optical coherence tomography 3 scanner (OCT3), have allowed greater accuracy in VKH disease diagnosis. The OCT3 examinations have shown that cystoid spaces appear in the neurosensory layer (between the inner and outer segments of photoreceptors) and not in the subretinal space. This structural finding was also supported by functional studies with multifocal electroretinography that measured the photoreceptors activity. Antimetabolites (azathioprine, mycophenolate mofetil and methotrexate), T-cell inhibitors (cyclosporine and tacrolimus) and biologic agents, associated with the well known glucocorticosteroids therapy, showed good results in acute and chronic phases of the disease. Intravitreal triamcinolone and bevacizumab were reported to have encouraging results for progressive or stubborn cases of VKH disease.

SUMMARY

To uphold visual acuity, an early, fast and accurate diagnosis is necessary, followed by an aggressive and lengthy immunosuppressive treatment.

Cutaneous GVHD is associated with the expansion of tissue-localized Th1 and not Th17 cells

Studies in mice have shown that proinflammatory Th17 cells can cause acute graft-versus-host disease (aGVHD) related tissue damage; however, whether they play a role in human aGVHD remains unclear. In a prospective study, we measured the proportion of Th17 cells in the blood and skin of patients at the onset of aGVHD. We found no difference in the proportion or amount of IL-17 produced by T cells in the blood of patients with aGVHD (n = 20) compared with time-matched patients without GVHD (n = 14). Moreover, Th17 cells were not increased in the skin of patients with cutaneous aGVHD (n = 7) compared with healthy controls (n = 10). In contrast, we found significantly more interferon-γ-producing T cells in the skin of patients with aGVHD compared with controls. These data support the long-standing paradigm that tissue localized interferon-γ-producing cells are the perpetrators of aGVHD.