A genome-wide association study identifies a functional ERAP2 haplotype associated with birdshot chorioretinopathy.

Birdshot chorioretinopathy (BSCR) is a rare form of autoimmune uveitis that can lead to severe visual impairment. Intriguingly, >95% of cases carry the HLA-A29 allele, which defines the strongest documented HLA association for a human disease. We have conducted a genome-wide association study in 96 Dutch and 27 Spanish cases, and 398 unrelated Dutch and 380 Spanish controls. Fine-mapping the primary MHC association through high-resolution imputation at classical HLA loci, identified HLA-A*29:02 as the principal MHC association (odds ratio (OR) = 157.5, 95% CI 91.6-272.6, P = 6.6 × 10(-74)). We also identified two novel susceptibility loci at 5q15 near ERAP2 (rs7705093; OR = 2.3, 95% CI 1.7-3.1, for the T allele, P = 8.6 × 10(-8)) and at 14q32.31 in the TECPR2 gene (rs150571175; OR = 6.1, 95% CI 3.2-11.7, for the A allele, P = 3.2 × 10(-8)). The association near ERAP2 was confirmed in an independent British case-control samples (combined meta-analysis P = 1.7 × 10(-9)). Functional analyses revealed that the risk allele of the polymorphism near ERAP2 is strongly associated with high mRNA and protein expression of ERAP2 in B cells. This study further defined an extremely strong MHC risk component in BSCR, and detected evidence for a novel disease mechanism that affects peptide processing in the endoplasmic reticulum.

Early- and late-stage ocular complications of herpes zoster ophthalmicus in rural South Africa.

OBJECTIVES: To describe the spectrum of ocular complications of herpes zoster ophthalmicus (HZO) in rural South Africa. METHODS: Patients presenting with visual complaints and active or healed HZO at the ophthalmology outpatient department of three hospitals in rural South Africa were included in this study. Demographic and clinical data were collected, and HIV status was determined for all participants. RESULTS: Forty-eight patients were included, and 81% were HIV infected. Poor vision was reported by 94% of patients, painful eye by 79% and photophobia by 63%. A diverse spectrum of ocular complications was observed with corneal inflammation and opacification in 77% followed by anterior uveitis in 65%. The majority (65%) presented with late-stage ocular complications associated with irreversible loss of vision whereas early-stage complications, such as punctate epithelial keratitis and anterior uveitis, were less common. Blindness of the affected eye was observed in 68% of patients with late-stage complications. There was a considerable delay between onset of symptoms and first presentation to the ophthalmology outpatient department (median time 35 days; range 1-2500 days), and longer delay was associated with late-stage ocular complications (P = 0.02). CONCLUSIONS: HZO patients present with relatively late-stage ocular complications, and blindness among these patients is common. The delayed presentation to the ophthalmology outpatient department of hospitals in our rural setting is of concern, and efforts to improve ocular outcomes of HZO are urgently needed.

Ocular infections in sub-Saharan Africa in the context of high HIV prevalence.

Healthy eyes and good vision are important determinants of populations' health across the globe. Sub-Saharan Africa is affected by simultaneous epidemics of ocular infections and human immunodeficiency virus (HIV). Ocular infection and its complications, along with cataract and ocular trauma, are common conditions in this region with great impact on daily life. In this review, we discuss the epidemiology, clinical manifestations and microbial aetiology of the most important infectious ocular conditions in sub-Saharan Africa: conjunctivitis, keratitis and uveitis. We focus specifically on the potential association of these infections with HIV infection, including immune recovery uveitis. Finally, challenges and opportunities for clinical management are discussed, and recommendations made to improve care in this neglected but very important clinical field.

Perigranuloma localization and abnormal maturation of B cells: emerging key players in sarcoidosis?

RATIONALE: Recent observations of abnormal immunoglobulin responses and case reports describing successful B-cell ablative therapy suggest involvement of B cells in the pathogenesis of sarcoidosis. OBJECTIVES: To investigate how abnormal B-cell maturation and function in patients with sarcoidosis contribute to disease. METHODS: Patients with sarcoidosis (n = 32) were included for detailed analysis by immunohistochemistry of tissue, flow cytometry of blood B-cell subsets, and serum immunoglobulin levels. Vaccination responses in patients with sarcoidosis to influenza virus and encapsulated bacteria and molecular analysis of immunoglobulin heavy chain transcripts were studied for functional analysis of immunoglobulin responses. MEASUREMENTS AND MAIN RESULTS: Perigranuloma localization of IgA-producing plasma cells and numerous B cells were found in affected tissues. Total blood B-cell numbers were normal, CD27(+) memory B cells were significantly reduced, and CD27(-)IgA(+) B cells were significantly increased; the results are normalized in patients treated with TNF-α blockers. Despite this, patients had normal serum immunoglobulin levels and normal antigen-specific immunoglobulin responses. IgA and IgG transcripts, however, showed high frequencies of somatic hypermutations and increased usage of downstream IgG subclasses, suggestive for prolonged or repetitive responses. CONCLUSIONS: The large B-cell infiltrates in granulomatous tissue and increased molecular signs of antibody maturation are indicative of direct involvement of B cells in local inflammatory processes in patients with sarcoidosis. Moreover, CD27(-)IgA(+) B cells could be a marker for treatment with TNF-α blockers. These findings of B cells as emerging key players provide a rationale for a systematic study on B-cell ablative therapy in patients with sarcoidosis.

Good visual outcome of tuberculous chorioretinitis after ART initiation in a HIV-infected patient.

Mycobacterium tuberculosis infection is an important cause of sight-threatening chorioretinitis in HIV-infected individuals living in M. tuberculosis endemic areas. We present a case of tuberculous chorioretinitis in a HIV-infected man after recent initiation of antiretroviral therapy in rural South Africa, who had nearly complete resolution of clinical signs and symptoms after standard tuberculosis treatment. His presentation was most likely associated with immune reconstitution inflammatory syndrome.

Multicolor flowcytometric immunophenotyping is a valuable tool for detection of intraocular lymphoma.

OBJECTIVE: Intraocular lymphoma (IOL) is a rare condition and frequently difficult to distinguish from uveitis or other uveitis-masquerading syndromes. The diagnosis is confirmed by cytologic examination of ocular fluid specimens and more recently by molecular-immunoglobulin heavy chain (IGH) translocation or cytokine analysis. However, some of these more recent methods have not been validated by follow-up studies. DESIGN: Evaluation of a diagnostic test. PARTICIPANTS: In a cohort of 51 consecutive patients with a clinical suspicion of IOL, vitreous analysis was performed via multicolor flowcytometric immunophenotyping. METHODS: Multicolor flowcytometric immunophenotyping was performed with CD45, CD3, CD19, CD20, anti-SmIgκ, and anti-SmIgλ antibodies. The presence of a clear B-cell population showing a disequilibrium of Igκ versus Igλ expression was used to confirm the diagnosis of non-Hodgkin lymphoma (NHL). Patients were followed for a minimum of 2 years (mean, 5.9 ± 2.0 years) to validate the accuracy of the method. MAIN OUTCOME MEASURES: The presence or absence of IOL during follow-up. RESULTS: In 14 of 51 patients, a clinical diagnosis of IOL was confirmed using flowcytometric analysis. Of these 14 patients, 11 had primary IOL and 3 had metastasized secondary lymphomas. In 3 of 51 patients who were diagnosed with (central nervous system) NHL during follow-up, the test failed to confirm the presence of a clonal B-cell population. In 18 of the 34 other patients, an infectious or well-defined immunologic disorder was established during follow-up. The remaining 16 patients, with a minimal follow-up of 2 years, were diagnosed with idiopathic uveitis. CONCLUSIONS: Multicolor flowcytometric analysis had 82.4% sensitivity and 100% specificity in patients with suspected IOL. This is comparable to the reported vitreous interleukin (IL)-6/IL-10 testing sensitivity of 0.8 and sensitivity of 0.65 to 0.95 by immunoglobulin heavy chain (IGH) gene arrangement testing in clinical cohorts. Because flowcytometric tests are readily performed in hematologic laboratories, this can be regarded as a useful method for confirming the clinical diagnosis of IOL. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

High prevalence of anelloviruses in vitreous fluid of children with seasonal hyperacute panuveitis.

Seasonal hyperacute panuveitis (SHAPU) is a potentially blinding ocular disease occurring in Nepal that principally affects young children. Random amplification of partially purified vitreous fluid (VF)-derived nucleic acid revealed the presence of human anelloviruses in VF of SHAPU patients. In a comparative study of patients with different ocular pathologies, SHAPU patients were at highest risk of harboring anelloviruses in their eyes. The majority of SHAPU patients had multiple anelloviruses in their VF. The ocular anellovirus load in SHAPU and non-SHAPU patients did not differ and no SHAPU-specific anellovirus variant was detected. Analysis of paired serum and VF samples from SHAPU and non-SHAPU patients showed that the anellovirus detected in VF samples most likely originated from the systemic viral pool during viremia, potentially through breakdown of the blood-ocular barrier. The detection of anelloviruses in VF samples of uveitis patients, profoundly so in SHAPU patients, is imperative and warrants elucidation of its clinical significance.

Identification of viral antigens recognized by ocular infiltrating T cells from patients with varicella zoster virus-induced uveitis.

PURPOSE: Varicella zoster virus (VZV) is a common cause of infectious uveitis associated with an intraocular inflammatory response involving virus-specific T cells. In the current study, the functional characteristics and the antigen specificity of VZV-reactive T cells recovered from intraocular fluid (IOF) samples of five patients with VZV were determined. METHODS: B-cell lines were infected with a comprehensive panel of recombinant vaccinia viruses expressing 11 individual VZV open reading frames (ORFs), or alternatively pulsed with the corresponding peptides to generate antigen-presenting cells (APCs). T-cell responsiveness of the IOF-derived VZV-specific T cells toward APCs was monitored by interferon (IFN)-gamma enzyme-linked immunosorbent spot-forming assays on bulk T-cell cultures and subsequently T-cell clones (TCCs). The cytokine-secretion profile and cytotoxicity of the VZV-specific TCCs was determined by ELISA and flow cytometry, respectively. RESULTS: T-cell reactivity to VZV proteins encoded by ORF4, -10, -14, -18, -29, -31, -61, -62, -63, -67, and -68 was demonstrated, but specificity varied individually. T-cell epitopes on ORF62 and -68 were delineated. The TCCs secreted IFNgamma, but relatively low levels of interleukin-4 and -5, in response to VZV antigen-expressing APCs. The TCCs induced antigen-specific cytotoxic T-cell activity. CONCLUSIONS: The results suggest that the intraocular VZV-specific T-cell response in the patients with VZV analyzed is directed to a broad spectrum of VZV antigens, including the latency-associated VZV proteins from ORFs 4, 29, 63, and particularly ORF62. This local T-cell response was in part mediated by cytotoxic CD4(+) T cells with a Th1/0-like effector memory phenotype.

Octreotide long-acting repeatable for the treatment of chronic macular edema in uveitis.

PURPOSE: To report on the efficacy of the somatostatin analog octreotide long-acting repeatable (LAR), in the treatment of uveitic chronic macular edema (CME). DESIGN: Case series, retrospective analysis. METHODS: In 20 patients, 20 episodes of recurrent CME during otherwise quiescent uveitis were treated with intramuscular octreotide LAR injections. Patients were included if CME control with acetazolamide or systemic and periocular steroids had failed during previous CME episodes or if contraindications existed for persistent use of these therapies. Mean outcome points were CME and visual acuity changes. Correlation of prognostic factors with these outcomes was analyzed. RESULTS: The included CME episodes occurred 7.6 +/- 1.4 years after onset of uveitis. Octreotide LAR treatment started 7.0 +/- 7.3 months after diagnosis of CME. CME decreased in 70% of episodes, after 2.7 +/- 1.3 months of treatment. After arrest of successful treatment, CME recurred instantly (27.2%) or within six months (36.4%). In 36.4% of successfully treated episodes, CME was absent for more than one year. A probable prognostic factor for success was the duration of CME before treatment. CONCLUSIONS: Octreotide LAR had an edema-reducing effect in 70% of treated CME episodes. Successful response was related to duration of CME before start of treatment. The early recurrence of CME (63.6%) after arrest of octreotide LAR advocates a long-term treatment in recent episodes of macular edema in otherwise quiescent uveitis.

Uveitis is predominantly of infectious origin in a high HIV and TB prevalence setting in rural South Africa.

AIMS: To determine the burden of disease in a unique sample of patients with uveitis from a rural South African setting. METHODS: Data in this cross-sectional study were collected from patients presenting with uveitis (n=103) at the ophthalmology outpatient department of three hospitals in rural South Africa. Demographic and clinical data were collected, and laboratory analysis of aqueous humour, serological evaluation and routine diagnostics for tuberculosis (TB) were performed. RESULTS: Sixty-six (64%) participants were HIV infected. Uveitis was predominantly of infectious origin (72%) followed by idiopathic (16%) and autoimmune (12%). Infectious uveitis was attributed to herpes virus (51%), Mycobacterium tuberculosis (24%) and Treponema pallidum (7%) infection. HIV-infected individuals were more likely to have infectious aetiology of uveitis compared with HIV-uninfected individuals (83% vs 51%; p=0.001). CONCLUSIONS: Microbial aetiology of uveitis is common in areas where HIV and TB are endemic. In these settings, a high index of suspicion for infectious origin of uveitis is warranted.

Somatostatin receptor scintigraphy patterns in patients with sarcoidosis.

PURPOSE: Sarcoidosis is a multisystem granulomatous disorder, most frequently involving the lungs, skin, or eyes. Somatostatin receptor scintigraphy (SRS) can visualize sarcoid granulomas through binding of a radionuclide-coupled somatostatin analog to somatostatin receptors that are expressed in sarcoidosis. Uptake and patterns on SRS were studied and correlated to clinical and conventional findings. PATIENTS AND METHODS: Data of 218 SRSs undertaken for the analysis of potential sarcoidosis were studied. These scintigraphies were retrospectively studied on intensity uptake degrees and localization of sarcoidosis-associated lesions, and compared with conventional radiological techniques (chest x-ray and CT). RESULTS: In all but 1 of the 175 evaluable patients, SRS demonstrated uptake. In patients with thoracic sarcoidosis-associated lesions, SRS improved the yield of visualization of chest x-ray in 20 (36%) and CT in 7 (32%) of histologically unproven patients, and in 31 (30%) and 8 (14%) of the histologically proven patients, respectively. Mediastinal lesions together with either eye, salivary glands, clavicular, or hilar localizations were most frequent demonstrated on SRS and constituted characteristic patterns. Exclusive extrapulmonary disease was found in 6% of the patients. CONCLUSIONS: Somatostatin receptor scintigraphy enhances the yield of investigations in sarcoidosis patients and therefore provides a useful and sensitive imaging technique to monitor organ involvement and therapeutic efficacy in patients with sarcoidosis.

Vgamma9Vdelta2 T cells recovered from eyes of patients with Behçet's disease recognize non-peptide prenyl pyrophosphate antigens.

The phenotype and antigen-specificity of T cells expanded by mitogenic stimulation from intra-ocular fluid (IOF) samples of affected eyes of six Behçet's disease (BD) patients, and seven patients with other uveitis entities, were determined. High numbers of gammadelta T cells, predominantly Vgamma9Vdelta2 T cells, were only detected in the IOF-derived TCL of three BD patients. Whereas no TCL responded to heat shock protein (HSP) 65 kDa, reactivity to isopentyl pyrophosphate (IPP) and related non-peptide prenyl pyrophosphates (PPP) was restricted to the gammadelta T cell containing TCL. Upon IPP stimulation, these TCL secreted IFN-gamma but no IL-4. By single-cell analysis of intracellular IFN-gamma production and CD69 expression the IOF-derived IPP-specific T cells were identified as CD4(-)CD8(-) gammadelta T cells. The data presented suggest the infiltration of PPP-specific Vgamma9Vdelta2 Th1-like cells into the eye of BD patients with uveitis.

Bevacizumab in age-related macular degeneration: a randomized controlled trial on the effect of injections every 4 weeks, 6 weeks and 8 weeks.

PURPOSE: Several clinical trials have established the efficacy of ranibizumab therapy administered every 4 weeks to treat exudative age-related macular degeneration (ARMD). Bevacizumab appears to be a cost-effective alternative to ranibizumab, although an optimal injection schedule has not yet been determined. In this study, we set out to determine whether bevacizumab treatment in exudative ARMD every 6 or 8 weeks is non-inferior to bevacizumab treatment every 4 weeks. METHODS: A total of 191 patients with exudative ARMD were randomly assigned to a 1-year continuous regimen of intravitreal bevacizumab every 4 (n = 64), 6 (n = 63) or 8 weeks (n = 64). The primary outcome was visual acuity change after 1 year of treatment. RESULTS: In all three treatment groups, visual acuity improved between baseline and 1 year. There was no statistically significant difference in the mean change of visual acuity score at 1 year for bevacizumab administered every 4 (1.96 ± 13.70), 6 (1.60 ± 10.98) or 8 weeks (5.98 ± 8.88). Reduction in central retinal thickness was observed in all three study groups. At 1 year, the mean decrease in central foveal thickness ranged from 86 ± 97 µm in the every 6 weeks group to 109 ± 90 µm in the group every 8 weeks group (p = 0.30). CONCLUSION: At 1 year, bevacizumab administered every 6 or 8 weeks was not inferior to therapy administered every 4 weeks.

Acyclovir-resistant herpes simplex virus type 1 in intra-ocular fluid samples of herpetic uveitis patients.

BACKGROUND: Acyclovir (ACV) is the antiviral drug of choice to treat patients with herpes simplex virus type 1 (HSV-1) uveitis. The prevalence of intra-ocular ACV-resistant (ACV(R)) HSV-1 in herpetic uveitis is unknown and may have clinical consequences. In addition to its predictive value on ACV susceptibility, the polymorphic HSV-1 thymidine kinase (TK) gene facilitates differentiation between HSV-1 strains. OBJECTIVES: The objective of this study was to determine the genetic composition and ACV susceptibility of the causative virus in intra-ocular fluid samples (IOF) of HSV-1 uveitis patients. STUDY DESIGN: The intra-ocular HSV-1 pool from 11 HSV-1 uveitis patients was determined by sequencing IOF-derived viral TK genes. The ACV susceptibility profile of the cloned intra-ocular TK variants was defined by mass spectrometry. In addition, the ganciclovir (GCV) susceptibility of the ACV(R) HSV-1 TK variants was defined. RESULTS: Intra-ocular fluid samples of HSV-1 uveitis patients contain HSV-1 quasispecies, principally consisting of one major and multiple genetically related minor patient-specific TK variants. Four of 10 patients analyzed had an intra-ocular ACV(R) HSV-1 of which 3 were cross-resistant to GCV. The ACV(R) profile of intra-ocular HSV-1 did not correlate with symptomatic ACV treatment. CONCLUSIONS: Affected eyes of HSV-1 uveitis patients are commonly infected with a patient-specific HSV-1 quasispecies, including one major and multiple genetically related minor variants. A relatively high prevalence of intra-ocular ACV(R) HSV-1, mainly ACV/GCV cross-resistant viruses, was detected in HSV-1 uveitis patients.

The neonatal Fc receptor is expressed by human retinal pigment epithelial cells and is downregulated by tumour necrosis factor-alpha.

BACKGROUND/AIMS: The neonatal Fc receptor (FcRn) protects immunoglobulin G (IgG) from catabolism, controls its transport between cell layers and extends its serum half-life. In the human, vitreous IgG can be found, but how vitreous IgG is processed or transported is currently unknown. The FcRn is a candidate molecule to regulate these processes. The authors examined FcRn expression and regulation in human retinal pigment epithelium (RPE) cells. METHODS: In three primary RPE cell cultures (from three donor eyes) and in the human RPE cell line ARPE-19, FcRn and beta-2-microglobulin (ß2M) mRNA levels were determined by real-time quantitative PCR. FcRn protein expression was analysed by western blot studies. Stimulation experiments were performed with recombinant human tumour necrosis factor (TNF)-α and interferon (IFN)-γ. HT-29, THP-1 and HeLa cell lines were used as FcRn positive and negative non-ocular controls, respectively. RESULTS: Expression of FcRn mRNA and protein was demonstrated in all three RPE cultures. After stimulation with TNF-α, FcRn expression is downregulated in RPE cells and upregulated in HT-29 and THP-1 cells. IFN-γ has no effect on FcRn expression in RPE cells. CONCLUSIONS: Human RPE cells express FcRn. The proinflammatory cytokine TNF-α downregulates FcRn expression. The authors speculate that the FcRn may play a pivotal role in the immune privilege of the human eye.

Human ocular-derived virus-specific CD4+ T cells control varicella zoster virus replication in human retinal pigment epithelial cells.

PURPOSE: Varicella zoster virus (VZV)-induced retinitis is characterized by the presence of virus-infected cells in the retinal layer and the ocular infiltration of VZV-specific T cells. Herein, the susceptibility of human retinal pigment epithelial (RPE) cells to VZV infection and the ability of virus-specific CD4(+) T cells to control VZV infection in RPE cells in vitro is addressed. METHODS: Human primary RPE cell cultures (n=2) were infected with a VZV strain expressing green fluorescent protein. The infection and viability of infected RPE cells was monitored by flow cytometry or by a fluorescent imager on RPE monolayers. RPE cells, pretreated with or without interferon-gamma (IFN-gamma), were infected with VZV and subsequently cultured with VZV-specific CD4(+) T-cell clones (TCCs; n=3) recognizing disparate VZV proteins presented by different HLA class II alleles. IFN-gamma production and cytotoxicity of the TCCs in response to VZV-infected RPE cells was determined by flow cytometry. RESULTS: Human RPE cells are permissive to a productive VZV infection. VZV-infected RPE cells presented the cognate antigen to the CD4(+) TCCs only if the RPE cells were pretreated with IFN-gamma and expressed the appropriate HLA class II allele. VZV-specific TCCs inhibited productive VZV infection in RPE cells, which was in part attributed to TCC-mediated killing of the VZV-infected RPE cells. CONCLUSIONS: The results presented suggest that RPE cells may play a role as retina-resident antigen-presenting cells in the intraocular, VZV-specific, T cell-mediated inflammatory response of VZV-induced uveitis.