Anti-retinal auto-antibodies in Vogt-Koyanagi-Harada syndrome, Behcet's disease, and sympathetic ophthalmia

Approaches based on miRNAs in Behçet's Disease: Unveiling pathogenic mechanisms, diagnostic strategies, and therapeutic applications

Behçet's Disease (BD) is an intricate medical puzzle, captivating researchers with its enigmatic pathogenesis. This complex ailment, distinguished by recurrent mouth and genital lesions, eye irritation, and skin injuries, presents a substantial obstacle to therapeutic research. This review explores the complex interaction of microRNAs (miRNAs) with BD, highlighting their crucial involvement in the disease's pathophysiology. miRNAs, recognized for regulatory influence in diverse biological processes, hold a pivotal position in the molecular mechanisms of autoimmune diseases, such as BD. The exploration begins with examining miRNA biogenic pathways and functions, establishing a foundational understanding of their regulatory mechanisms. Shifting to the molecular landscape governing BD, the review highlights miRNA-mediated impacts on critical signaling pathways like Notch, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and protein kinase B (AKT)/mammalian target of rapamycin (mTOR), offering insights into intricate pathophysiological mechanisms. Dissecting the immunological landscape reveals the profound influence of miRNAs on BD, shedding light on the intricate modulation of immune responses and offering novel perspectives on disease etiology and progression. Beyond molecular intricacies, the review explores the clinical relevance of miRNAs in BD, emphasizing their potential as diagnostic and prognostic indicators. The discussion extends to the promising realm of miRNA-based therapeutic interventions, highlighting their potential in alleviating symptoms and altering disease progression. This comprehensive review, serving as a valuable resource for researchers, clinicians, and stakeholders, aims to decipher the intricate molecular tapestry of BD and explore the therapeutic potential of miRNAs.

Autoimmune-Related Retinopathy Presenting As Plaquenil Toxicity in Patients With Systemic Lupus Erythematosus

Purpose: To report 3 cases of autoimmune retinopathy (AIR) in patients with systemic lupus erythematosus (SLE) to explore the association between these conditions and highlight additional clinical consideration of AIR in patients presenting with atypical retinopathy in the context of hydroxychloroquine use. Methods: The medical and clinical follow-up records of 3 clinical cases were reviewed. The eligibility criteria were the absence of other retinopathy or systemic autoimmune diseases. Results: All patients had a long-standing diagnosis of SLE and had been taking hydroxychloroquine at a dose exceeding the American Academy of Ophthalmology recommendations. All 3 patients had extensive retinal degeneration atypical in appearance for drug toxicity alone. Examination, imaging, electroretinograms, and autoantibody assays eventually led to the diagnosis of AIR. Conclusions: Further study of the AIR and SLE may reveal an association between these conditions. In patients with SLE presenting with retinal degeneration, AIR may be underdiagnosed.

Insights gained from single-cell analysis of immune cells in tofacitinib treatment of Vogt-Koyanagi-Harada disease

Vogt-Koyanagi-Harada disease (VKH) is an important refractory uveitis mediated by pathological T cells (TCs). Tofacitinib (TOFA) is a JAK- targeted therapy for several autoimmune diseases. However, the specific pathogenesis and targeted therapeutics for VKH remain largely unknown. Based on single-cell RNA sequencing and mass cytometry, we present what we believe is the first multimodal, high-dimensional analysis to generate a comprehensive human immune atlas regarding subset composition, gene signatures, enriched pathways, and intercellular interactions of VKH patients undergoing TOFA therapy. Patients with VKH are characterized by TCs' polarization from naive to effector and memory subsets, together with accrued monocytes and upregulated cytokines and JAK/STAT signaling pathways. In vitro, TOFA reversed Th17/Treg imbalance and inhibited IL-2-induced STAT1/3 phosphorylation. TOFA alleviated VKH symptoms by restoring pathological TCs' polarization and functional marker expression and downregulating cytokine signaling and lymphocyte function. Remarkably, inflammation-related responses and intercellular interactions decreased after TOFA treatment, particularly in monocytes. Notably, we identified 2 inflammation- and JAK-associated monocyte subpopulations that were strongly implicated in VKH pathogenesis and mechanisms involved in TOFA treatment. Here, we provide a potentially novel JAK-targeted therapy for VKH and elaborate on the possible therapeutic mechanisms of TOFA, expanding our knowledge of VKH pathological patterns.

Peripheral immune landscape and natural killer-like B cells in human Vogt-Koyanagi-Harada disease

Vogt-Koyanagi-Harada (VKH) disease is a systemic autoimmune disorder threatening the eyesight. The pathogenic mechanisms and biomarkers reflecting disease severity and predicting treatment response require further exploration. Here, we performed a single-cell analysis of peripheral blood mononuclear cells (PBMC) obtained from eight patients with VKH disease and eight healthy controls to comprehensively delineate the changes in VKH disease. We showed a mixture of inflammation, effector, and exhausted states for PBMCs in VKH disease. Notably, our study implicated a newly identified B cell subset, natural killer-like B cells (K-BC) characterized by expressing CD19 and CD56, was correlated with VKH disease. K-BCs expanded in VKH disease, fell back after effective treatment, and promoted the differentiation of pathogenic T cells. Overall, we mapped the peripheral immune cell atlas in VKH disease and indicated the pathogenic role and potential value in predicting treatment response of K-BCs.

Reflectance adaptive optics findings in a patient with Vogt-Koyanagi-Harada disease

Purpose

To describe the reflectance adaptive optics scanning laser ophthalmoscopy (AOSLO) findings in different stages of Vogt-Koyanagi-Harada (VKH) disease and correlate them to visual gain post treatment. Confocal (cAOSLO) and non-confocal split-detector AOSLO (sdAOSLO) were used to assess longitudinally the status of the photoreceptors in a patient with VKH managed on corticosteroid and immunomodulatory therapy.

Observation

A 32-year-old Japanese American female presented with a 2-week history of blurred vision in both eyes (OU) and worsening headache previously diagnosed as a case of VKH and treated with high dose oral prednisone. At the time of presentation, though vision was improving, and frank serous retinal detachments were absent, spectral domain optical coherence tomography (SD-OCT) showed presence of residual subretinal fluid with disruption of the photoreceptor inner segments and outer segments (IS/OS) involving OU. The photoreceptor mosaic at the foveal center appeared very sparse with large areas devoid of visible photoreceptors on cAOSLO, in agreement with the SD-OCT data. sdAOSLO imaging over the same location shows a higher number of contiguous photoreceptors. After imaging, the patient was started on mycophenolate mofetil as steroid-sparing long-term therapy. Three months later, visual acuity improved to 20/20 OU, and SD-OCT showed almost complete resolution of subretinal fluid with significant improvement of the IS/OS SD-OCT signal, OU. cAOSLO imaging revealed a contiguous photoreceptor mosaic without gaps and of normal appearance.

Conclusions and Importance

VKH patients may demonstrate transient photoreceptor abnormalities on SD-OCT and cAOSLO imaging. sdAOSLO imaging revealed intact photoreceptor segments in areas that appeared as voids on cAOSLO, which later showed structural recovery on SD-OCT and cAOSLO. Therefore, sdAOSLO may predict potential for improvement in patients wherein there appears to be photoreceptor loss in cAOSLO and/or SD-OCT.

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

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

Correlation of Immunological Markers with Disease and Clinical Outcome Measures in Patients with Autoimmune Retinopathy

Purpose

To determine if immunological markers (1) are significantly different between autoimmune retinopathy (AIR) patients and controls and (2) correlate with disease progression in AIR patients.

Methods

We enrolled patients with a possible AIR diagnosis, as well as control participants without eye disease, autoimmunity, or cancer. Immunological markers were tested in all participants. In addition, AIR patients had up to three blood draws for testing over their disease course. For AIR patients, clinical measures, including visual acuity (VA) and Goldmann visual field (GVF) area, were recorded at each draw. We used the Mann-Whitney U test to compare the immunological markers between AIR patients and controls. We used multilevel mixed-effect regression to investigate the correlation between markers and clinical parameters over time in AIR patients.

Results

Seventeen patients with AIR and 14 controls were included. AIR patients had a higher percent of monocytes (Z = 3.076, P = 0.002). An increase in immunoglobulin G against recoverin was correlated with a VA decrease (β = 0.0044, P < 0.0001). An increase in monocyte proportion was correlated with a decrease in GVF area (β = -7.27, P = 0.0021). Several markers of B-cell depletion were correlated with GVF improvement.

Conclusions

Monocytes may play a role in AIR pathophysiology and be a disease activity marker. B-cell depletion markers correlated with clinical parameter improvement, particularly GVF.

Translational Relevance

This work elucidates immunologic markers that may improve the accuracy of diagnosis and treatment of AIR.

New Pharmacological Strategies for the Treatment of Non-Infectious Uveitis. A Minireview

Non-infectious uveitis (NIU) is a group of disorders characterized by intraocular inflammation at different levels of the eye. NIU is a leading cause of irreversible blindness in working-age population in the developed world. The goal of uveitis treatment is to control inflammation, prevent recurrences, and preserve vision, as well as minimize the adverse effects of medications. Currently, the standard of care for NIU includes the administration of corticosteroids (CS) as first-line agents, but in some cases a more aggressive therapy is required. This includes synthetic immunosuppressants, such as antimetabolites (methotrexate, mycophenolate mofetil, and azathioprine), calcineurinic inhibitors (cyclosporine, tacrolimus), and alkylating agents (cyclophosphamide, chlorambucil). In those patients who become intolerant or refractory to CS and conventional immunosuppressive treatment, biologic agents have arisen as an effective therapy. Among the most evaluated treatments, TNF-α inhibitors, IL blockers, and anti-CD20 therapy have emerged. In this regard, anti-TNF agents (infliximab and adalimumab) have shown the strongest results in terms of favorable outcomes. In this review, we discuss latest evidence concerning to the effectiveness of biologic therapy, and present new therapeutic approaches directed against immune components as potential novel therapies for NIU.

Non-paraneoplastic related retinopathy: clinical challenges and review

Autoimmune retinopathy (AIR) is a rare inflammatory condition characterized by progressive visual loss, abnormalities in visual fields and electroretinographic exams, along with presence of circulating anti-retinal antibodies. There are two main forms of AIR: paraneoplastic AIR (pAIR) and presumed non-paraneoplastic AIR (npAIR). NpAIR is considered a diagnosis of exclusion, since it is typically made after other causes of retinopathy have been investigated and the absence of malignancy is confirmed. Work-up of a npAIR case is challenging since there are no standartizaded protocols for diagnosis and treatment. The treatment regimen may vary from case to case, and it can be best guided by a set of parameters including electrophysiological responses, visual outcomes, and presence of anti-retinal antibodies. The purpose of this review is to summarize the principal clinical features, investigation, and management of npAIR.

Prevalence and clinical impact of antiretinal antibodies in uveitis

PURPOSE

To determine the prevalence of serum antiretinal antibodies (ARAs) among patients with uveitis and establish their clinical relevance.

METHODS

This prospective study assessed the presence of ARAs by indirect immunofluorescence (IIF) using primate retina in 126 patients with uveitis and 60 healthy controls. Clinical data of uveitis patients were collected from medical charts and included the classification of uveitis, cause of uveitis or its association with systemic disease, stage and activity of uveitis and specific retinal features. Correlations between the presence of specific ARAs and various clinical characteristics were analysed.

RESULTS

The presence of ARAs was observed in 49 of 104 (47%) of patients with uveitis and in 10 of 59 (17%) of healthy controls (p < 0.001). Staining of the nuclear layers or the photoreceptors were both more often observed in patients with uveitis compared to healthy controls (p = 0.002 and p = 0.018, respectively). No specific associations were found between the presence of serum ARAs and various clinical characteristics.

CONCLUSION

Serum ARAs were more frequent in patients with uveitis compared to healthy controls, but their clinical role remains elusive. The assessment of intraocular production of specific ARAs may provide further insight into the role of ocular autoantibodies in diverse uveitis entities.

Vogt-Koyanagi-Harada disease: review of a rare autoimmune disease targeting antigens of melanocytes

Vogt-Koyanagi-Harada disease (VKHD) is a rare granulomatous inflammatory disease that affects pigmented structures, such as eye, inner ear, meninges, skin and hair. This disease is mainly a Th1 lymphocyte mediated aggression to melanocytes after a viral trigger in the presence of HLA-DRB1*0405 allele. The absence of ocular trauma or previous intraocular surgery sets VKHD appart from sympathetic ophthalmia, its main differential diagnosis. The disease has an acute onset of bilateral blurred vision with hyperemia preceded by flu-like symptoms. The acute uveitic stage is characterized by a diffuse choroiditis with serous retinal detachment and optic disc hyperemia and edema. Fluorescein angiography in this phase demonstrates multiple early hyperfluorescent points. After the acute uveitic stage, ocular and integumentary system pigmentary changes may appear. Ocular findings may be accompanied by lymphocytic meningitis, hearing impairment and/or tinnitus in a variable proportion of patients. Prompt diagnosis followed by early, aggressive and long-term treatment with high-dose corticosteroids is most often ensued by good visual outcomes. However, some patients may experience chronic uveal inflammation with functional eye deterioration. The current review discusses the general features of VKHD, including epidemiology, classification into categories, differential diagnosis and current therapeutic approaches.

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.

Correlation between Fluorescein Angiographic Findings and Visual Acuity in Behçet Retinal Vasculitis

PURPOSE

To identify significant fluorescein angiographic (FA) characteristics associated with visual acuity (VA) in Behçet retinal vasculitis.

MATERIALS AND METHODS

Retrospective review of 86 eyes of 48 patients (age: 35.6±10.2 years) with Behçet retinal vasculitis were performed. VA and FA findings as well as correlation between them were assessed.

RESULTS

The mean initial VA of eyes with posterior pole-involved vasculitis (63 eyes; 73.3%) was significantly worse than that of those with peripheral vasculitis (23 eye; 26.7%) (logarithm of the minimum angle of resolution VA: 0.554±0.572 vs. 0.078±0.148; p<0.0001). Subgroup analysis revealed a more severe and diffuse pattern of vascular leakage in posterior pole-involved vasculitis compared to peripheral vasculitis (p<0.0001). Retinal vascular leakage (β=0.345; p<0.0001), optic disc hyperfluorescence (β=0.147; p=0.032), and macular leakage (β=0.107; p=0.047) were significantly associated with worse initial VA. During the follow up (mean: 33.3±17.9 months), the change of leakage showed no significant correlation with change of VA in posterior pole-involved vasculitis (τ=0.199, p=0.092).

CONCLUSION

Posterior pole involvement, the degree of retinal vascular leakage, optic disc hyperfluorescence, and macular leakage are significantly associated with VA in Behçet retinal vasculitis.

Diagnostic features of the autoimmune retinopathies

The term autoimmune retinopathy encompasses a spectrum of rare autoimmune diseases that affect retinal function, often but not exclusively at the level of the photoreceptor. They typically present with painless visual loss, which may be accompanied by normal fundus examination. Some are progressive, often rapidly. They present a diagnostic challenge because there are no standardised clinical or laboratory based diagnostic criteria. Included within the spectrum are cancer-associated retinopathy, melanoma-associated retinopathy and presumed non-paraneoplastic autoimmune retinopathy. Differentiation from other retinopathies can be challenging, with overlap in symptoms, signs, and investigation findings, and an absence of pathognomonic features. However, technological developments in ophthalmic imaging and serological investigation over the past decade are adding novel dimensions to the investigation and classification of patients with these rare diseases. This review addresses the clinical, imaging, and serological features of the autoimmune retinopathies, and discusses the relative strengths and limitations of candidate diagnostic features.

Autoimmune retinopathy

PURPOSE OF REVIEW

Autoimmune retinopathy (AIR) is an immune-mediated disorder characterized by progressive visual loss, abnormal electroretinographic and visual field findings in the presence of circulating anti-retinal antibodies. This review highlights advances made toward understanding the pathophysiology, clinical manifestations, and trends in the management of AIR.

RECENT FINDINGS

The pathophysiology of AIR is likely antibody-mediated. AIR serum autoantibodies are variable in their size and retinal tissue they target and can also be present in healthy controls and multiple autoimmune diseases. Rarely, AIR may be associated with dysregulated self-tolerance mechanisms in the thymus. Despite progress in research, our understanding of AIR remains incomplete. Lack of standardized methods for anti-retinal antibody testing continues to challenge the interpretation of seropositivity. Conventional immunosuppressives have been further studied, and promising immunomodulatory therapies, such as targeted B-cell therapy, have been introduced. Newer imaging modalities such as fundus autofluorescence and spectral domain optical coherence tomography may be helpful in diagnosis, monitoring progression of disease and response to treatment.

SUMMARY

AIR is a rare but vision-threatening disease whose pathogenesis is poorly defined. Lack of standardized clinical or laboratory criteria further complicates the diagnosis and management. Despite recent progress, further basic science research into the autoimmune process is needed. Prospective controlled clinical trials with immunomodulatory therapy can help define future treatment paradigms.

Proliferative vitreoretinopathy may be a risk factor in combined macular hole retinal detachment cases

OBJECTIVE

To review the incidence and closure rate of full-thickness macular holes (MH) in cases associated with concomitant rhegmatogenous retinal detachment (RRD).

METHODS

A retrospective consecutive case series was performed from patients undergoing surgical repair of RRD and simultaneous closure of MH. The presence of proliferative vitreoretinopathy (PVR), rates of hole closure and reattachment, and visual acuity outcomes were evaluated.

RESULTS

There were a total of 607 RRDs during the study period. The incidence of concomitant MH in RRD cases was 2.3% (14 of 607), and the overall incidence of PVR was 15.8% (96 of 607). All eyes with a MH had a primary break that was distinct from the MH. Five patients did not meet the inclusion criteria for review of the postoperative outcomes. In the remaining 9 patients, the retinal reattachment rate was 100%, and MH closure was achieved in 8 of 9 (89%) eyes after a single surgery. At the time of primary repair, PVR was present in 6 of these 9 cases (66.7%). There was a significant association between the presence of PVR and a concomitant MH (P = 0.0027). The mean preoperative visual acuity was 2.59 ± 0.649 logarithm of the minimum angle of resolution units and significantly improved to 1.23 ± 1.01 logarithm of the minimum angle of resolution units (P = 0.00124). Overall, 88.8% of patients showed an improvement in visual acuity at the final postoperative visit, and a visual acuity of 20/125 or better was achieved in 66.7% of cases.

CONCLUSION

Macular holes combined with a RRD are infrequent, and good anatomical results can be achieved after a simultaneous repair. Also, PVR may be more frequently encountered in this particular subset of RRDs.

Inflammatory cytokine and chemokine expression in sympathetic ophthalmia: a pilot study

Sympathetic ophthalmia is a bilateral uveitis that develops after penetrating injury to one eye. This study aimed to identify the inflammatory cellular sub-phenotypes and expression of pertinent inflammatory cytokines/chemokines in sympathetic ophthalmia (SO). Dalen-Fuchs nodules (DFN), granulomas, and non-granulomatous foci of inflammation were micro-dissected from 15 cases. RNA was extracted, and quantitative PCR was performed to measure IL-17, IL-18, IL-23, IFN-γ, CCL19, CXCL11, CCL17, and CCL22 transcripts. Immunohistochemical methods were used to characterize CD3, CD4, CD8, CD20, CD68, and CD163 expression. Non-granulomatous lymphocytes were predominantly CD3-positive and expressed more IFN-γ than cells within granulomas, consistent with Th1 cells. In contrast, granulomas and DFN contained mainly CD68+, CD163+/- and expressed more IL-17, IL-18, IL-23, CCL19, and CXCL11 than non-granulomatous cells. Our data indicate for the first time that M1 macrophages are the predominant inflammatory cells within granulomas and DFN of SO. We further observed high levels of IL-17 within granulomas and the presence of Th1 and M1 cells.

The role of perivascular melanophage infiltrates in the conjunctiva in sympathetic ophthalmia

PURPOSE

To report pathologic changes in the conjunctiva from the exciting eye in a case of sympathetic ophthalmia (SO).

METHODS

Report of clinical findings and conjunctival histopathology in a patient with SO.

RESULTS

A 50-year-old male developed SO, with unusual peribulbar conjunctival pigmentation in the inciting eye. Histological examination of the conjunctival biopsy revealed perivascular distribution of CD68(+) melanophages that also expressed HLA-DR, suggesting that these macrophages may act as antigen-presenting cells. In addition, increased CD4(+) and CD3(+) lymphocytes were noted in the subconjunctival space when compared to specimens of normal conjunctiva and traumatic uveal prolapse without SO, suggesting T-cell recruitment.

CONCLUSIONS

These pathologic findings suggest a possible mechanism by which local antigen processing by subconjunctival melanophages may play a role in the initiation of the complex cell-mediated response seen in SO.

Ophthalmopathology in rats with MBP-induced experimental autoimmune encephalomyelitis

PURPOSE

Multiple studies indicate that T-cells play a major role in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis, but recently an involvement of antibodies has also been discussed. The aim of our study was to examine the effects of myelin basic protein (MBP) immunization on survival of neurons, alteration of antibody reactivity, and microglia in the retinal ganglion cell layer.

METHODS

EAE was induced in rats by immunization with MBP. Intraocular pressure (IOP) measurements and funduscopies were performed regularly. Neuron cell density was evaluated on cresyl-stained retinal flatmounts. IgG antibody deposition and activated microglia were detected in retina and optic nerve sections via immunohistology. The intensity of autoreactive IgG antibodies was quantified in successive serum samples via tissue arrays.

RESULTS

Significant loss of neurons was detected 6 weeks after immunization (p < 0.05). At the same time, IgG antibody deposits accumulated in the retina and the optic nerve of EAE animals and a significant microglia turn-over to activation was observed. The level of IgG antibody reactivity against retina and optic nerve tissue continuously increased (p < 0.05). While clinical parameters indicated typical EAE progression, we observed no changes in IOP (p > 0.9) or abnormalities in fundi.

CONCLUSIONS

Immunization with MBP not only causes neuron loss in the retinal ganglion cell layer, but also triggers antibody reactivity against ocular tissue. Possibly some of these antibodies are involved in the induction of neuronal apoptosis. This study suggests that, apart from T-cell mediation, alteration of antibody reactivity and activated microglia do also influence the ocular pathomechanisms in the EAE model.

Increased frequency of anti-retina antibodies in asymptomatic patients with chronic t. gondii infection

PURPOSE

To search for anti-retina antibodies that serve as markers for eye disease in uveitis.

MATERIALS AND METHODS

Stored sera from patients with uveitis, ocular toxoplasmosis (n = 30) and non-infectious, immune-mediated uveitis (n = 50) and from asymptomatic individuals who were positive (n = 250) and negative (n = 250) for anti-Toxoplasma antibodies were tested. Serum anti-retina IgG was detected by an optimized ELISA using a solid-phase whole human retina extract, bovine S-antigen or interphotoreceptor retinoid-binding protein.

RESULTS

Uveitis patients showed a higher mean reactivity to whole human retina extract, interphotoreceptor retinoid-binding protein and S-antigen in comparison to the asymptomatic population. These findings were independent of the uveitis origin and allowed the determination of the lower anti-retina antibody cut-off for the three antigens. Asymptomatic anti-Toxoplasma serum-positive individuals showed a higher frequency of antihuman whole retina extract antibodies in comparison to asymptomatic anti-Toxoplasma serum-negative patients. The bovine S-antigen and interphotoreceptor retinoid-binding protein ELISAs also showed a higher mean reactivity in the uveitis groups compared to the asymptomatic group, but the observed reactivities were lower and overlapped without discrimination.

CONCLUSION

We detected higher levels of anti-retina antibodies in uveitis patients and in a small fraction of asymptomatic patients with chronic toxoplasmosis. The presence of anti-retina antibodies in sera might be a marker of eye disease in asymptomatic patients, especially when whole human retina extract is used in a solid-phase ELISA.

Vogt-Koyanagi-Harada Disease

Vogt-Koyanagi-Harada disease (VKH) is a multisystem autoimmune disorder principally affecting pigmented tissues in the ocular, auditory, integumentary and central nervous systems. Patients are typically 20 to 50 years old and have no history of either surgical or accidental ocular trauma. Pigmented races are more commonly affected. Depending on revised diagnostic criteria, the disease is classified as complete, incomplete or probable based on the presence of extraocular findings (neurological, auditory and integumentary). The clinical course of VKH is divided into four phases: prodromal (mimics a viral infection), uveitic (bilateral diffuse uveitis with papillitis and exudative retinal detachment), convalescent (tissue depigmentation), and chronic recurrent (recurrent uveitis and ocular complications). The pathogenesis of VKH is thought to be related to an aberrant T cell-mediated immune response directed against self-antigens found on melanocytes. VKH has been linked to human leukocyte antigen DR4 (HLA-DR4) and HLA-Dw53, with strongest associated risk for HLA-DRB1*0405 haplotype. The diagnosis of VKH is clinical, and differential includes sympathetic ophthalmia, sarcoidosis, primary intraocular B-cell lymphoma, posterior scleritis, and uveal effusion syndrome. Treatment is typically initiated with high-dose oral corticosteroids, but other immunomondulatory agents (most oftentimes cyclosporine) may be needed for non-responsive patients or when corticosteroid side-effects are not tolerated. Visual prognosis is generally good with prompt diagnosis and aggressive immunomodulatory treatment.

Uveitic foveal atrophy: clinical features and associations

OBJECTIVE

To characterize foveal atrophy in a heterogeneous group of patients with uveitis using clinical findings and high-definition (HD) optical coherence tomography (OCT).

DESIGN

Cross-sectional, retrospective case series.

RESULTS

The HD-OCT scans of 140 patients seen in a tertiary referral center were reviewed and 23 patients (33 eyes) with foveal atrophy were identified. All of the patients with foveal atrophy were diagnosed with intermediate uveitis, posterior uveitis, or panuveitis. The status of the photoreceptor layer as visualized with HD-OCT was associated with significant differences in mean visual acuity (P < .001). Clinical findings associated with foveal atrophy included atrophy of the retinal pigment epithelium and choroid (30 eyes [91%]), macular ischemia (13 eyes [39%]), cystoid macular edema (5 eyes [15%]), choroidal neovascularization (4 eyes [12%]), retinal detachment involving the macula (2 eyes [6%]), and serum antiretinal antibodies (2 eyes [6%]).

CONCLUSIONS

Foveal atrophy can be a complication of intraocular inflammation in a variety of uveitic syndromes. The cause of foveal atrophy is multifactorial and may include dysfunction and atrophy of the retinal pigment epithelium and choroid, cystoid macular edema, macular ischemia secondary to occlusive retinal vasculitis, choroidal neovascularization, retinal detachment, and possibly antibody-mediated damage directed against photoreceptors. Careful observation of the photoreceptor layer using HD-OCT may help to identify patients who are at risk for visual loss secondary to foveal atrophy.

The need for standardization of antiretinal antibody detection and measurement

PURPOSE

To review the current literature on the detection and measurement of antiretinal antibodies.

DESIGN

Collaborative essay.

METHODS

Literature review and interpretation.

RESULTS

There is strong evidence to suggest a role for antiretinal antibodies, particularly those targeting recoverin and alpha-enolase, in the pathogenesis of autoimmune retinopathy (AIR). Additionally, numerous other autoantibodies have been described as putative mediators of retinal degeneration and more remain to be discovered. However, assay methods described in the literature by many laboratories for the detection of circulating antiretinal antibodies have been varied and diverse, making it difficult to interpret and compare their results.

CONCLUSIONS

There is currently little standardization of laboratory methods used to detect and monitor antiretinal antibodies. To measure and monitor levels of circulating antiretinal antibodies optimally in patients with AIR, development of standardized assays with stringent internal controls is required. A multicenter collaborative and validation effort is encouraged to reach a consensus on this issue.

The importance of 'Mechnikov's thorn' for an improved understanding of 21st century medicine and immunology: a view from the eye

In 1908, Ehrlich and Mechnikov shared the Nobel Prize in Medicine for their independent studies that set the scene for the modern understanding of innate and adaptive immunity. However, 20th century immunology thinking was dominated by aberrant adaptive immunity but this never adequately explained the full spectrum of inflammatory disease. This article draws on medical observations, from where immunology originated, and uses the example of the eye to illustrate how the integration of medicine and immunology leads to an improved understanding of inflammation against self. The spectrum of ocular inflammation can be viewed as either predominantly adaptive immune mediated (mostly the realm of immunology), or predominantly due to ocular tissues factors that lead to regional innate immune activation (the realm of medicine), or a variable interaction between the two. Just as the thorns that Mechnikov inserted into molluscs lead to localized innate immune activation; ocular inflammation can likewise be driven by non-immune factors that include tissue degeneration or microdamage. The present article emphasizes the importance of such factors in the initiation or phenotypic expression of ocular immunopathology allowing different immunological dogmas including self-non-self discrimination, immunological tolerance and immunoprivilege to be viewed in a different light. This scheme also leads to an appreciation of how the innate immune system may be the sole perpetuator of some ocular immunopathologies. We propose that this integrated view of medicine and immunology is crucial for understanding immunology from a translational angle and has implications far beyond ocular disease.

Immunological protein expression profile in Ccl2/Cx3cr1 deficient mice with lesions similar to age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of blindness in the United States. Ccl2 knock-out (KO) mice sporadically develop the cardinal features of AMD in their senescent stage. Humans bearing a loss of function variant or single nucleotide polymorphism (SNP) in CX3CR1 are at increased risk of developing AMD. We recently developed Ccl2(-/-)/Cx3cr1(-/-) mice, which consistently develop retinal degeneration with many AMD features. Since there is strong evidence for an immunological role in AMD pathogenesis, we examined ocular immune protein expression levels in Ccl2(-/-)/Cx3cr1(-/-), Ccl2(-/-), Cx3cr1(-/-), and age-matched wild-type (WT) mice. Immunohistochemistry revealed increased complement C3d in Bruch's membrane, retinal pigment epithelium (RPE), choroidal capillaries, and particularly drusen of the Ccl2(-/-)/Cx3cr1(-/-) mice relative to the WT controls. No change was detected in single KO mice. Real-time RT-PCR revealed a 2.5-fold increase in C3 expression in the Ccl2(-/-)/Cx3cr1(-/-). While the retinas of four month old WT and Ccl2(-/-) showed minimal immunoreactivity for markers of macrophages and microglia, infiltrates of these mononuclear phagocytic cells were detected in the Ccl2(-/-)/Cx3cr1(-/-)retinal lesions and a few foci in the Cx3cr1(-/-) retina. The Ccl2(-/-)/Cx3cr1(-/-) had reduced toll-like receptor 4 (TLR4) expression in the RPE. Following LPS injection, the Ccl2(-/-)/Cx3cr1(-/-) had significantly reduced endotoxin-induced uveitis scores and showed a diminished increase in Tlr4 mRNA expression. No changes in TLR4 expression were detected in either single KO. Autoantibodies against the retina and photoreceptors were also detected in the Ccl2(-/-)/Cx3cr1(-/-) serum. Real-time RT-PCR revealed significant increases in Ccl5 transcript in the Ccl2(-/-)/Cx3cr1(-/-) relative to the WT. These results suggest that innate immunity and possibly adaptive immunity play an important role in Ccl2(-/-)/Cx3cr1(-/-) retinal degeneration. Moreover, since human AMD patients show similar immunopathological profiles, these results support the Ccl2(-/-)/Cx3cr1(-/-) as a suitable model for human AMD.

[Vogt-Koyanagi-Harada syndrome]

INTRODUCTION

Vogt-Koyanagi-Harada syndrome is a rare, inflammatory disease with manifestations affecting the ocular, central nervous, audito-vestibular, and integumentary systems. Vogt-Koyanagi-Harada syndrome is more frequent in Asia but is also described in Europe. We report three new non asiatic cases of this syndrome.

OBSERVATIONS

The three patients had bilateral panuveitis and hypoacusia. Two of them had peripheral facial palsy, two of them had vestibular syndrome and one of them lymphocytic meningitis. In each case we found characteristic HLA II typing and in one case we discovered the simultaneous presence of three auto-antibodies: anti-retina (anti-Arrestin type), anti-choroid and anti-cochlea. These patients were treated by corticosteroids but required an additional treatment by cyclophosphamide (0.8g/m2). The clinical course was favorable with visual sequelae for two and auditory one for one.

DISCUSSION

These biological and therapeutic elements and a review of the recent literature are in favor of an autoimmune origin of this syndrome.

Incidence of antiretinal antibodies in melanoma: screening of 77 serum samples from 51 patients with American Joint Committee on Cancer stage I-IV

BACKGROUND

Patients with melanoma-associated retinopathy (MAR) experience different visual symptoms caused by the production of antitumoral antibodies that cross-react with retinal epitopes. Immunofluorescence assays of serum from patients with MAR on sectioned monkey or human retina characteristically reveal antibody activity located within the inner nuclear layer, with a focus of activity upon the membranes of bipolar cells.

OBJECTIVES

We inquired into the association with disease of this serological abnormality by evaluating sera from patients with melanoma with no MAR-like signs or symptoms.

METHODS

Groups of patients were selected with different stages of melanoma (American Joint Committee on Cancer stages I-IV). Seventy-seven serum samples from 51 patients with melanoma were examined by indirect immunohistochemical assay on sections of human retina.

RESULTS

Of the 77 serum samples, 53 were found to contain antibodies reactive with various components of retina. Eight were from 17 sera from patients in stage I or II, 14 were from 23 sera from patients in stage III, and 31 were from 37 sera from patients in stage IV. Statistical analysis revealed a correlation between antibody activity and the stage of disease, with a higher percentage of antibody activity in advanced stages (P = 0.002).

CONCLUSIONS

The presence of antiretinal antibodies in patients with melanoma without ocular symptoms appears to be more common than previously suspected. Antibody activity similar to that ascribed to the MAR syndrome appears in some patients with melanoma who have no MAR-like retinopathy. Follow-up studies will determine if patients with antiretinal antibodies go on to develop MAR and if staining intensity and staining patterns change over the course of the disease.

Immunopathology of the noninfectious posterior and intermediate uveitides

The posterior and intermediate uveitides share an underlying immune etiology; however, they can be clinically and immunopathologically distinguished. Although the initiating stimuli for posterior and intermediate uveities are not known, it is believed that an exogenous agent (such as a bacterium or a virus) or an endogenous molecule may induce disease. In either case, T-helper lymphocytes in conjunction with human leukocyte antigens are likely to be involved. This review examines the epidemiology, histology, immunopathology, and theories of pathogenesis of several posterior and intermediate uveitides, including sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome, Behçet's disease, sarcoidosis, intermediate uveitis, white dot syndromes, and birdshot retinochoroidopathy.

An association between Vogt-Koyanagi-Harada disease and Guillain-Barré syndrome

PURPOSE

To describe an association between Vogt-Koyanagi-Harada disease and Guillain-Barré syndrome.

METHODS

Case series, describing three patients.

RESULTS

In two patients, the disorders had their onsets within 2 weeks of each other; in the third patient, Vogt-Koyanagi-Harada disease occurred after 3 months, as Guillain-Barré syndrome resolved. All three patients had bilateral panuveitis typical of Vogt-Koyanagi-Harada disease. Each also developed well-accepted manifestations of Guillain-Barré syndrome, including paresis of the lower extremities (all patients), paresis of the upper extremities (two patients), paresis of cranial nerves (two patients), areflexia (all patients), and abnormal electromyography findings (two patients).

CONCLUSIONS

Vogt-Koyanagi-Harada disease may follow or occur simultaneously with Guillain-Barré syndrome. The fact that these two autoimmune disorders occur together in some patients suggest that they may share common disease mechanisms.

Revised diagnostic criteria for Vogt-Koyanagi-Harada disease: report of an international committee on nomenclature

PURPOSE

To present revised criteria for the diagnosis of Vogt-Koyanagi-Harada disease, a chronic, bilateral, granulomatous ocular and multisystem inflammatory condition of unknown cause.

METHODS

Diagnostic criteria and nomenclature were subjects of discussion at the First International Workshop on Vogt-Koyanagi-Harada Disease on October 19-21, 1999, at the University of California, Los Angeles, Conference Center, Lake Arrowhead, California. A committee appointed by the workshop participants was charged with drafting revised criteria for Vogt-Koyanagi-Harada disease, based on discussions held during the conference. This article is the consensus committee report.

RESULTS

New criteria, taking into account the multisystem nature of Vogt-Koyanagi-Harada disease, with allowance for the different ocular findings present in the early and late stages of the disease, were formulated and agreed upon by the committee. These criteria are based on additional knowledge and experience of experts in the field and are believed to reflect disease features more fully than previously published criteria.

CONCLUSIONS

The revised definition of Vogt-Koyanagi-Harada disease, with expanded diagnostic criteria, will facilitate performance of studies involving homogeneous populations of patients, at various stages of disease, that address unanswered questions regarding treatment and disease mechanisms.

High incidence of glucose intolerance in Vogt-Koyanagi-Harada disease

AIMS

To evaluate glucose tolerance of patients with Vogt-Koyanagi-Harada (VKH) disease before systemic corticosteroid therapy, and to assess changes brought on by treatment.

METHODS

20 VKH patients with acute bilateral panuveitis were studied. 20 healthy adults and 11 Behçet's disease patients with active uveoretinitis served as controls. A 75 g oral glucose tolerance test (OGTT) was given in the acute stage of ocular inflammation before systemic corticosteroid therapy. The OGTT was repeated in the convalescent stage of VKH disease in the patients with glucose intolerance before treatment. Insulin response was examined at the same time as the OGTT when possible.

RESULTS

55% of VKH patients (11/20) showed glucose intolerance but no apparent insulin secretion deficiency was detected. Four of seven patients in the convalescent stage showed improvement of glucose tolerance. None of the normal controls or disease controls showed glucose intolerance.

CONCLUSION

A high incidence of glucose intolerance was found in the acute stage of VKH disease. However, glucose intolerance improved in most cases after systemic corticosteroid therapy. It is possible that glucose intolerance seen in VKH patients may be related to the autoimmune inflammatory process of this disease.

Increased intraocular pressure during treatment for chronic uveitis

OBJECTIVES

(1) To prospectively evaluate the incidence of increased intraocular pressure (IOP) in patients suffering from chronic uveitis. (2) To identify the main factors responsible for an increase in the IOP among these patients.

METHODS

Two hundred and one patients suffering from chronic uveitis were included. Enrolled patients had an initial IOP of 8-18 mmHg. The patients were treated and clinically monitored during a period of 4 years. The IOP was measured at each visit and its changes followed prospectively. All patients were followed up for at least 12 months after enrollment.

RESULTS

Twenty-four (12%) of the 201 patients had IOP higher than 24 mmHg at two or more consecutive visits. Of these 24 patients, 19 suffered from bilateral uveitis and 5 had unilateral disease. Four of the 19 patients with bilateral uveitis developed a constant IOP higher than 24 mmHg in both eyes, while in 15 patients an IOP higher than 24 mmHg persisted only in one eye. A close association between the increased IOP and the use of corticosteroids was found in 18 of the 24 cases (75%). This association was ascertained in 16 of these patients by the decrease in IOP levels on discontinuation of the corticosteroid regimen and the renewed increase IOP was due to pupillary block in three cases (12.5%), to iris and angle neovascularization in two (8.3%), and to the inflammatory process per se in one case only (4.2%).

CONCLUSIONS

This study demonstrates that a persistent elevation of the IOP in patients suffering from chronic uveitis is, in the majority of cases, associated with the use of corticosteroids.

Cytomegalovirus DNA identified in skin biopsy specimens of patients with vitiligo

BACKGROUND

Viral infections have been implicated in the pathogenesis of a variety of autoimmune diseases.

OBJECTIVE

This investigation was undertaken to determine the presence or absence of viral genomes in the depigmented and uninvolved skin of patients with vitiligo.

METHODS

A polymerase chain reaction assay was used to detect viral genomes in paraffin-embedded skin biopsy specimens. Twenty-nine patients with vitiligo and 22 control subjects were included. Biopsy specimens were screened in a blinded fashion for a panel of DNA and RNA viruses including herpes simplex, varicella-zoster, cytomegalovirus (CMV), Epstein-Barr, HIV, and human T-cell lymphotropic virus.

RESULTS

CMV DNA was identified in 38% of the patients studied. Twenty-one percent had indeterminate results. Results in all control subjects were negative. Polymerase chain reaction screening for identification of other viral genomes was negative. Although not statistically significant, data trends suggested a correlation between the presence of CMV DNA in biopsy specimens and active vitiligo of relatively brief duration. In addition, CMV-positive patients had a statistically significant increased frequency of other concurrent autoimmune diseases.

CONCLUSION

CMV DNA in the depigmented and uninvolved skin of some patients with vitiligo and its absence in control subjects suggest that vitiligo may indeed be triggered by a viral infection in select patients.

Vogt-Koyanagi-Harada syndrome

The Vogt-Koyanagi-Harada syndrome (VKH) is a bilateral, diffuse granulomatous uveitis associated with poliosis, vitiligo, alopecia, and central nervous system and auditory signs. These manifestations are variable and race dependent. This inflammatory syndrome is probably the result of an autoimmune mechanism, influenced by genetic factors, and appears to be directed against melanocytes. On histopathologic examination typical cases show nonnecrotizing diffuse granulomatous panuveitis with initial sparing and late involvement of the choriocapillaris and formation of Dalen-Fuchs' nodules. Fluorescein angiography, lumbar puncture, and echography are useful adjuncts in the diagnosis and management of VKH syndrome. Patients with this syndrome are treated generally with high dose systemic corticosteroids or, when necessary, with cyclosporine or cytotoxic agents. The prognosis of patients with VKH syndrome is fair, with nearly 60% of patients retaining vision of 20/30 or better. The complications of VKH syndrome that lead to visual loss include cataracts in about 25% of patients, glaucoma in 33%, and subretinal neovascular membranes (SRNVMs) in about 10%; the latter, however, are an important cause of late visual loss. These complications usually require medical and/or surgical intervention, including photocoagulation. The major risk factor for the development of cataracts, SRNVMs, and, to some extent, glaucoma, is chronic recurrent intraocular inflammation that may be resistant to corticosteroid therapy. It appears that initial treatment with high dose corticosteroids, combined with prolonged corticosteroid therapy at appropriate dosage, may minimize these complications and may improve visual prognosis.

Allergic- and immunologic-mediated diseases of the eye and adnexae

Significant allergic- and immunologic-mediated diseases of the eye are reviewed. Included are diseases of the lacrimal gland namely keratoconjunctivitis sicca, immune-mediated diseases of the conjunctiva, atopic blepharoconjunctivitis, and marginal blepharitis, uveitis including lens-induced uveitis, episcleritis, orbital cellulitis, and optic neuritis. Significant diagnostic features, an approach to diagnostic workup, and treatment are presented.