Characterization of T cells and cytokines in the aqueous humour (AH) in patients with Fuchs' heterochromic cyclitis (FHC) and idiopathic anterior uveitis (IAU)

Role of CD4+ T cell-derived cytokines in the pathogenesis of uveitis

Uveitis refers to a diverse group of inflammatory diseases that affecting the uveal tract, comprising the iris, ciliary body, and choroid, with potential repercussions ranging from visual impairment to blindness. The role of autoimmunity in uveitis etiology is complex and still under investigation. CD4+ T cells intricately regulate immune responses in uveitis through their diverse subtypes: Th1, Th2, Th17, Treg (T regulatory), and Tfh (follicular T helper) cells. Each T cell subtype secretes specific cytokines with either pathogenic or protective implications in uveitis. Th1 cells, characterized by IFN-γ secretion and T-bet expression, drive type 1 immune responses against intracellular pathogens. Conversely, Th2 cells, which produce interleukin (IL)-4, IL-5, and IL-13 and express the transcription factor GATA3, mediate type 2 immune responses to larger extracellular threats like helminths. Th17 cells, generating IL-17 and IL-22 and controlled by RORγt, engage in type 3 immune responses against select pathogens. Tfh cells, releasing IL-21 and governed by Bcl6, aid B cell antibody production. Conversely, Tregs, identified by Foxp3, exert regulatory functions in immune homeostasis. This review delves into the roles of CD4+ T cell-derived cytokines in uveitis, emphasizing their intricate involvement in disease progression and resolution. Insight into these mechanisms might guide therapeutic approaches targeting CD4+ T cell responses in uveitis management.

Cytokines in Immune-mediated "Non-infectious" Uveitis

Uveitis is a significant cause of ocular morbidity and accounts for approximately 5 - 10% of visual impairments worldwide, particularly among the working-age population. Infections are the cause of ~ 50% cases of uveitis, but it has been suggested that infection might also be implicated in the pathogenesis of immune-mediated "non-infectious" uveitis. There is growing evidence that cytokines (i.e., interleukins, interferons, etc.) are key mediators of immune-mediated "non-infectious" uveitis. For example, activation of the interleukin-23/interleukin-17 signalling pathway is involved in immune-mediated "non-infectious" uveitis. Studies in animal models have been important in investigating the role of cytokines in uveitis. Recent studies of clinical samples from patients with uveitis have allowed the measurement of a considerable array of cytokines even from very small sample volumes (e.g., aqueous and vitreous humour). The identification of complex patterns of cytokines may contribute to a better understanding of their potential pathogenetic role in uveitis as well as to an improved diagnostic and therapeutic approach to treat these potentially blinding pathologies. This review provides further insights into the putative pathobiological role of cytokines in immune-mediated "non-infectious" uveitis.

Mechanisms of blood-retinal barrier disruption related to intraocular inflammation and malignancy

Blood-retinal barrier (BRB) disruption is a common accompaniment of intermediate, posterior and panuveitis causing leakage into the retina and macular oedema resulting in vision loss. It is much less common in anterior uveitis or in patients with intraocular lymphoma who may have marked signs of intraocular inflammation. New drugs used for chemotherapy (cytarabine, immune checkpoint inhibitors, BRAF inhibitors, EGFR inhibitors, bispecific anti-EGFR inhibitors, MET receptor inhibitors and Bruton tyrosine kinase inhibitors) can also cause different types of uveitis and BRB disruption. As malignant disease itself can cause uveitis, particularly from breast, lung and gastrointestinal tract cancers, it can be clinically difficult to sort out the cause of BRB disruption. Immunosuppression due to malignant disease and/or chemotherapy can lead to infection which can also cause BRB disruption and intraocular infection. In this paper we address the pathophysiology of BRB disruption related to intraocular inflammation and malignancy, methods for estimating the extent and effect of the disruption and examine why some types of intraocular inflammation and malignancy cause BRB disruption and others do not. Understanding this may help sort and manage these patients, as well as devise future therapeutic approaches.

Features of hemodynamic and immunological parameters in patients with recurrent uveitis complicated by hypertension, Fuchs heterochromic uveitis and Posner-Schlossman syndrome

Introduction: Uveitis is a disease that manifests with increased vascular permeability and occlusion, with some ischemia and inflammatory mediators. It is characterized by a wide range of pathological processes, including inflammation, increased vascular permeability and occlusion, local ischemia and cell alteration by inflammatory mediators, and is characterized by the presence of complications. Aim: To study the state of ocular hemodynamics by rheoophthalmography, as well as the immune status in patients with idiopathic recurrent anterior uveitis complicated by intraocular hypertension, Fuchs heterochromic uveitis, Posner-Schlossman syndrome, during the relapse period. Materials and methods: 93 patients with idiopathic recurrent anterior uveitis were included in this study, 8 patients with Fuchs' uveitis, and 6 patients with Posner-Schlossman syndrome. According to clinical signs, relapse and remission were considered. The control group (healthy volunteers of the same age) consisted of 27 people. In this regard, 5 groups of subjects were formed. The mean age of the patients was (M ± SD) 39.2 ± 14.6 years. According to the Median (range), the duration of the disease in patients was 2033 (350-3285) days, intraocular hypertension being recorded at P0 > 20 mm Hg. Statistical analysis was carried out in spreadsheets using STATISTICA 8.0 (StatSoft.Inc) program. Quantitative indicators were evaluated according to the correspondence to the normal distribution and to the Kolmogorov-Smirnov criterion. With a normal distribution, arithmetic means (M) and standard deviations (SD), limits of the 95% confidence interval (95% CI) and Student's t-test were calculated. Results: The volumetric blood filling of the eye according to the rheoophthalmographic indicator RQ during the period of remission of uncomplicated and complicated by hypertension anterior uveitis was reduced by 32.4%-40.5%, respectively, compared with the norm. During the period of relapse, RQ was significantly higher by 28% (p<0.05) than in remission, in the group of uncomplicated uveitis, and in the group of uveitis with increased IOP, no significant differences between the periods of remission and relapse were observed, which reflected the ischemic process in the relapse period. Volumetric blood filling in Fuchs and Posner-Schlossman syndromes in the acute period did not differ from the norm. Cellular immunity in the groups of uncomplicated and complicated by intraocular hypertension idiopathic uveitis, as well as with Fuchs and Posner-Schlossman syndromes, had a higher level of CD4 helper lymphocytes and a lower level of CD8 suppressor lymphocytes, which reflected higher values of the immunoregulatory index. The increase in the immunoregulatory index is most pronounced in Fuchs and Posner-Schlossman syndromes. Discussion: In the presented study, the incidence of idiopathic recurrent anterior uveitis complicated by intraocular hypertension was 9,9% among all cases of idiopathic recurrent anterior uveitis in one-time period. According to literature, this complicated form of uveitis occurs in 11,5%-46,1% of cases. Most often (up to 92% of cases), the anterior chamber angle was open. Conclusions: Different activity of the mechanisms regulating the balance of cellular and humoral immunity, sensitivity of T-cells to eye antigens in idiopathic anterior uveitis, Fuchs and Posner-Schlossman syndromes was assumed. Peculiarities of eye hemodynamics in these forms of uveitis were also revealed. Abbreviations: IOP = intraocular pressure, IOHS = inflammatory ocular hypertension syndrome, HSV = herpes simplex virus, CMV = cytomegalovirus, OCT = optical coherence tomography, OD = right eye, OS = left eye.

Cytokines, chemokines and growth factors profile in human aqueous humor in idiopathic uveitis

To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.

Interleukins and cytokine biomarkers in uveitis

Interleukins and cytokines are involved in the pathogenesis of uveitis of heterogeneous origin. Understanding the basics of the ocular immune privilege is a fulcrum to discern their specific role in diverse uveitis to potentially translate as therapeutic targets. This review attempts to cover these elements in uveitis of infectious, noninfectious and masquerade origin. Insights of the molecular targets in novel therapy along with the vision of future research are intriguing.

CD4- and CD8-expressing cells in the chambers of normal, cataract and uveitic eyes: A comparative study in dogs

The main aims of this study were to determine whether CD4⁺ and CD8⁺ cells are present in the normal chambers of the eye in dogs and to verify the hypothesis that uncomplicated cataract may be associated with the local recruitment of CD4⁺ and CD8⁺ cells. The presence of CD4⁺ and CD8⁺ cells was detected in aqueous humor (AH) of normal and cataract eyes. The study did not reveal differences in the percentage and absolute number of CD4⁺ cells between normal and cataract eyes. However, the values of these parameters in AH from cataract eyes were approximately 2- and 3-fold higher than in normal eyes, respectively. The mean percentage and absolute count of CD8⁺ cells increased approximately by 2.7- and 6-fold, respectively, in AH samples from cataract eyes compared to normal ones. The absolute count of CD4⁺ and CD8⁺ cells in AH of uveitic eyes was approximately 5- and 3-fold higher than in cataract eyes. The results indicate that CD4⁺ and CD8⁺ cells occur constitutively in the normal chambers of the eye in dogs. However, it should be pointed out that both of these cell populations appeared in trace amounts. The development of uncomplicated cataract in dogs may not be immunologically neutral in terms of the local immune response, but it may be associated with the recruitment of CD8⁺ cells into the eye chambers. This event does not seem to be of an inflammatory nature because it appears on a scale a few times smaller than in the course of uveitis.

Virus-associated anterior uveitis and secondary glaucoma: Diagnostics, clinical characteristics, and surgical options

In this retrospective, single-center, observational study, we compared the clinical characteristics, analyzed the glaucoma development, and the glaucoma surgery requirement mediators in patients with different virus-associated anterior uveitis (VAU). In total, 270 patients (= eyes) with VAU confirmed by positive Goldmann-Witmer coefficients (GWC) for cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), rubella virus (RV), and multiple virus (MV) were included. Clinical records of these patients were analyzed. Demographic constitution, clinical findings, glaucoma development, and surgeries were recorded. The concentrations of 27 immune mediators were measured in 150 samples of aqueous humor. The GWC analysis demonstrated positive results for CMV in 57 (21%), HSV in 77 (29%), VZV in 45 (17%), RV in 77 (29%), and MV in 14 (5%) patients. CMV and RV AU occurred predominantly in younger and male patients, while VZV and HSV AU appeared mainly with the elderly and females (P<0.0001). The clinical features of all viruses revealed many similarities. In total, 52 patients (19%) showed glaucomatous damage and of these, 27 patients (10%) needed a glaucoma surgery. Minimal-invasive glaucoma surgery (MIGS) showed a reliable IOP reduction in the short-term period. In 10 patients (37%), the first surgical intervention failed and a follow-up surgery was required. We conclude that different virus entities in anterior uveitis present specific risks for the development of glaucoma as well as necessary surgery. MIGS can be suggested as first-line-treatment in individual cases, however, the device needs to be carefully chosen by experienced specialists based on the individual needs of the patient. Filtrating glaucoma surgery can be recommended in VAU as an effective therapy to reduce the IOP over a longer period of time.

Aqueous cytokine levels in four common uveitis entities

To investigate aqueous cytokine profiles in acute anterior uveitis (AAU), Fuchs' syndrome, Vogt-Koyanagi-Harada (VKH) disease and Behcet's disease (BD), we assayed the concentrations of 17 cytokines by multiplex immunoassay in aqueous humor (AqH) collected during cataract surgery from 24 AAU, 29 Fuchs' syndrome, 29 VKH disease, 30 BD and 30 senile cataract control patients. Aqueous cytokine levels were compared between the five groups and analysed by logistic regression. Cytokine levels were then compared between uveitis patients who underwent cataract surgery within 3 months and those who underwent this surgery more than 3 months after complete control of intraocular inflammation. The results showed that aqueous levels of interferon (IFN)-γ, monocyte chemotactic protein (MCP)-1, macrophage inflammatory protein (MIP)-1β and tumour necrosis factor (TNF)-α levels in AqH from patients with Fuchs' syndrome were significantly higher than those in the other four groups. Using multivariate analysis, MIP-1β was found to be significantly associated with Fuchs' syndrome. There was no difference in aqueous cytokine levels between cases having cataract surgery within 3 months compared to those after 3 months of complete control of their intraocular inflammation. The current study shows that Chinese patients with Fuchs' syndrome appear to have a specific cytokine profile. MIP-1β is an important chemokine in the intraocular environment of Fuchs' syndrome. Aqueous cytokine profiles support the performance of cataract surgery in uveitis within 3 months after intraocular inflammation control.

A literature review on Fuchs uveitis syndrome: An update

Fuchs uveitis syndrome is a chronic, typically unilateral, ocular condition characterized by an asymptomatic mild inflammatory syndrome that can result in cataract and secondary glaucoma. Diagnosis is largely clinical because the etiology remains obscure. Fuchs uveitis syndrome is most likely the result of different insults or pathogenic mechanisms, including infections, autoimmune diseases, hereditary and sympathetic dysfunction. According to the infectious theory, the infection of herpes simplex virus, ocular toxoplasmosis, cytomegalovirus, rubella virus, and other viruses have been implicated in the pathogenesis of the disease. There is no indication for corticosteroid therapy in Fuchs patients, and treatment should be mostly reserved to cataract and glaucoma. Phacoemulsification with intraocular lens implantation is a safe procedure with good visual outcomes in patients with Fuchs uveitis syndrome. Glaucoma is often unresponsive to treatment and should actively be monitored both preoperatively and postoperatively in these patients. We discuss the current understanding of Fuchs uveitis syndrome from its clinical presentations through recommended management and provide a comprehensive description and the updated knowledge of its pathophysiology.

Aqueous humor IL-8, IL-10, and VEGF levels in Fuchs' uveitis syndrome and Behçet's uveitis

PURPOSE

This study investigated the levels of interleukin (IL)-8, IL-10, and vascular endothelial growth factor (VEGF) in the aqueous humor (AqH) of patients with Behçet's uveitis (BU) and Fuchs' uveitis syndrome (FUS) during an inactive period and compared these levels with those in the AqH of noninflammatory healthy control subjects.

METHODS

This prospective and case-control study included 33 patients (16 patients with BU and 17 patients with FUS) and 35 control subjects. IL-8, IL-10, and VEGF levels in the AqH were quantified by performing sandwich enzyme-linked immunosorbent assay. Kruskal-Wallis test was used to compare the cytokine levels in the different groups, and statistical significance was set at p < 0.05.

RESULTS

IL-8 levels were significantly higher in the AqH of patients with BU and FUS than in the AqH of control subjects (p < 0.001 and p < 0.001, respectively). IL-10 levels were significantly lower in the AqH of patients with BU than in the AqH of patients with FUS and of control subjects (p = 0.001 and p < 0.001, respectively). Although VEGF levels were higher in the AqH of patients with FUS than in the AqH of patients with BU and of control subjects, the difference was significant only between patients with FUS and control subjects (p < 0.001).

CONCLUSIONS

We observed a significant decrease in IL-10 levels in the AqH of patients with BU and a significant increase in VEGF levels in the AqH of patients with FUS compared to controls. IL-8 and VEGF levels showed no significant difference among uveitis patients.

Different composition of intraocular immune mediators in Posner-Schlossman-Syndrome and Fuchs' Uveitis

Posner-Schlossman-Syndrome (PSS) is clinically characterized by acute, recurrent, mild, unilateral uveitis anterior accompanied by elevated intraocular pressure (IOP). Fuchs´ Uveitis (FU) is a chronic, low-grade-inflammatory disorder, involving anterior uvea and vitreous. The clinical findings show remarkable similarities as well as differences. In our study, we determine the composition of immune mediators in aqueous humor of patients with PSS and FU and evaluate if immune mediators play a crucial role in specific viral intraocular inflammation and IOP rises. Aqueous humor samples from 81 uveitis patients (= eyes) presenting with either PSS or FU were collected at one time point. Local intraocular antibody synthesis to rubella virus was confirmed in 65 patients, whereas 16 were tested positively for human cytomegalovirus. Thirteen patients with PSS and 10 patients with FU were treated with glaucoma medications. Additionally, 11 cataract patients acted as control group. Immune mediator concentrations were measured by Bio-Plex Pro assay. We observed in both PSS (IFN-γ: 174.9 pg/mL; TNF-α: 25.1 pg/mL) and FU (IFN-γ: 25.4 pg/mL; TNF-α: 27.2 pg/mL) groups a significantly increased level of T-helper 1 immune mediators compared to controls (IFN-γ, TNF-α: 0 pg/mL) [median]. Notably, PSS patients (IL-1RA: 73.4 pg/mL; IL-8: 199.4 pg/mL; IL-10: 33.4 pg/mL; IP-10: 126350 pg/mL) showed a stronger and more active ocular inflammatory response, than FU patients (IL-1RA: 4.3 pg/mL; IL-8: 72.4 pg/mL; IL-10: 1.6 pg/mL; IP-10: 57400 pg/mL). Furthermore, a negative correlation between mediators and IOP was seen in the PSS group, potentially caused by acetazolamide-treatment. Our findings show that immune mediators play a crucial role in specific viral intraocular inflammation and influence IOP levels. Remarkable similarities but also significant differences of immune mediator concentrations are apparent in PSS compared to FU. High concentrations of IL-1RA, IL-8, IL-10, and IP-10 correlate with active inflammation in PSS, while FU may trigger chronic inflammation. Our data also substantiated a very similar composition of cytokines in those patients from the PSS group suffering from ocular hypertension and thus offers a potential explanation model for a negative correlation between mediators and IOP.

Immune Profiling of T Cells Infiltrating Vitreous Humor in Tubercular Uveitis

PURPOSE

To assess cellular composition and local cytokine response in vitreous humor of tubercular uveitis.

METHODS

Cells were collected from vitreous cassettes and peripheral blood of 8 tubercular uveitis and 5 control subjects, undergoing vitrectomy and analyzed by flow cytometry for cellular composition, activation status, proinflammatory cytokine expression, and uptake of TLR9 ligand, CpG ODN 2216.

RESULTS

CD3 + T cells with equal proportion of CD4+ and CD8 + T cells formed major fraction of infiltrating cells. The vitreous humor showed higher expression of recent activation marker, CD69, and proinflammatory cytokines, IFN-γ and IL-17A, in CD4 + T cells as compared to peripheral blood. Lastly, intraocular CD4 + T cells showed reduced uptake of ODN 2216 than peripheral blood.

CONCLUSIONS

Our results indicate that local antigenic stimuli trigger T cell infiltration and activation of CD4 + T cells that are hyporesponsive to TLR9 stimulation. These infiltrating T cells might be responsible in further aggravating ocular inflammation.

Monoclonal immunoglobulin heavy chain gene rearrangement in Fuchs' uveitis

Background

Fuchs’ uveitis (FU) is occasionarlly complicated with heavy vitreous opacity. We have performed vitrectomy procedures to remove vitreous opacity in affected patients as part of differential diagnosis for primary vitreoretinal lymphoma (PVRL).

Case presentation

We retrospectively reviewed the clinical records of five patients who first visited the Uveitis Clinic of the University of Tokyo Hospital between 2009 and 2013, were diagnosed with FU and underwent a vitrectomy for removal of dense vitreous opacity. All were diagnosed as FU by ocular findings and elevation of Goldmann-Witmer coefficient (GWC) value for the rubella virus (RV) antibody. In examinations of the vitreous body, cytological diagnosis, elevation of IL-10/IL-6 ratio, and the kappa/lambda ratio in flow cytometry findings were negative in all cases, whereas monoclonal immunoglobulin heavy chain (IgH) gene rearrangement was positive in 4 cases and negative in 1 case.

Conclusions

Although monoclonal IgH gene rearrangement is thought to be a reliable biomarker for PVRL, a high percentage of vitreous specimens from our FU patients showed pseudo-positive results. Ophthalmologists must take care regarding possible pseudo-positive findings when performing differential diagnosis between FU and PVRL. Combinations of results of cytological diagnosis, IL-10/IL-6 ratio, kappa/lambda ratio, and IgH gene rearrangement may be necessary for a definitive diagnosis of PVRL and differentiation from FU.

Fuchs' Uveitis Syndrome: No Longer a Syndrome?

PURPOSE

Rubella virus (RV) has a central role in the etiopathogenesis of Fuchs' uveitis syndrome (FUS). We aim to offer new insights by comprehensive analysis of recent laboratory and epidemiologic data.

METHODS

We conducted a literature search for laboratory data and papers on etiopathogenesis.

RESULTS

Aqueous humour samples of FUS patients show immunoreactivity to RV, in a specific and sensitive manner. Identification of RV genome confirm intraocular infection in a subset of FUS patients. Epidemiologic findings further support causality. The clinical spectrum of RV-associated uveitis is similar but not identical to FUS. FUS eyes exhibit a predominance of CD8 + T cells, high IFN-? and IL-10 levels.

CONCLUSIONS

RV is the leading cause of FUS. Cytokine-based findings mirror a viral etiology and chronic low-grade inflammation. RV-associated FUS represents a common pathway of intraocular RV inoculation after congenital or acquired infection. Other causes, including HSV and CMV, may lead to FUS.

Aqueous cytokine changes associated with Posner-Schlossman syndrome with and without human cytomegalovirus

AIM

To study the differences in aqueous cytokines in Posner-Schlossman Syndrome (PSS) patients with and without human cytomegalovirus (CMV) DNA in the aqueous humor.

METHODS

This is a prospective study. Fifty-three uveitis patients with clinical signs of PSS were enrolled and aqueous humor samples were collected. Fourteen PSS patients were positive of CMV DNA in the aqueous by polymerase chain reaction (PCR) analysis. These eyes were negative of common ocular pathogens such as herpes simplex virus, varicella-zoster virus, rubella virus and toxoplasma. Twenty-five otherwise healthy cataract patients were enrolled as controls. Cytokine concentration was measured by a magnetic color-bead-based multiplex assay and analyzed using statistical and classification approaches.

RESULTS

The average age of 53 PSS patients was 48.74±13.43 years (yrs) (mean ± standard deviation) and 66.3±15.0 yrs for the controls. The median CMV viral DNA copy number was 26000/mL aqueous (range 1400 to 85000 copies/mL) in 14 CMV positive patients as determined by quantitative PCR. PSS aqueous had significantly higher Interleukin (IL)-8 (CXCL8), monocyte chemotactic protein-1 (CCL2), macrophage inhibitory protein 1-β (CCL4), granulocyte colony-stimulating factor (GCSF) and transforming growth factor-β (TGF-β) levels than controls after adjusted by age and gender. IL-2, IL-12, tumor necrosis factor-α (TNF-α) and interferon-α (IFN-α) levels were significantly lower in PSS aqueous than controls. No difference between CMV positive PSS and CMV negative PSS aqueous was observed. Over 97% of PSS samples were distinguished from controls by elevated CXCL10 (>500 ng/mL), CXCL8 (>30 ng/mL) and CCL2 (>60 ng/mL) levels.

CONCLUSION

PSS eyes were characterized by elevated aqueous chemokine concentration. The presence of CMV viral DNA was not associated with significant change of the type of cytokine expression in PSS patients.

CD40 polymorphisms in Han Chinese patients with Fuch uveitis syndrome

PURPOSE

Polymorphisms of the cluster of differentiation 40 (CD40) gene have recently been identified to be associated with the risk to several immune diseases. The aim of this study was to determine the potential association of CD40 polymorphisms with Fuch uveitis syndrome (FUS).

METHODS

A total of 131 Han Chinese patients with FUS and 402 healthy controls were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Genotype counts in patients and controls were analyzed by the χ(2) test.

RESULTS

All genotypic and allelic frequencies of the tested two CD40 polymorphisms were in Hardy-Weinberg equilibrium. The genotypic and allelic frequencies of rs4810485 and rs1883832 were not different between patients with FUS and controls. No influence of sex could be found following stratification analysis according to gender.

CONCLUSIONS

Our results suggest that the two investigated single-nucleotide polymorphisms (SNPs), rs4810485 and rs1883832, in CD40 are not associated with FUS in the Han Chinese population.

Intraocular and serum cytokine profiles in patients with intermediate uveitis

PURPOSE

To study the intraocular and serum cytokine and chemokine profile in patients with intermediate uveitis (IU) at various stages of inflammatory activity.

METHODS

Institutional, prospective association study. Paired aqueous humor (AqH) and serum samples were collected from 36 consecutive IU patients and 10 controls. The concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10, IL-12p70, tumor necrosis factor (TNF)-α, CC--chemokine ligand 5/regulated upon activation normal T-cell expressed, and secreted (CCL5/RANTES), CC--chemokine ligand 3/macrophage inflammatory protein 1alpha (CCL3/MIP-1α), CCL4/MIP-1β, and CC--chemokine ligand 2/monocyte chemotactic protein--1 (CCL2/MCP-1) were measured in both AqH and serum by multiplex immunoassay. Main outcome measures were serum and intraocular levels of the analyzed cyto- and chemokines.

RESULTS

Patients with IU had higher serum levels of TNF-α than non-uveitic controls (p<0.0001), whereas their AqH TNF-α levels did not show a difference (p=0.323). IU patients had higher intraocular levels of IL-1β, IL-6, IL-8, IL-10, IL-12p70 and CCL2/MCP-1 than the controls (p=0.020, 0.001, <0.0001, 0.005, 0.003, and 0.003, respectively). Active stages of IU were characterized by higher levels of IL-6, IL-8, CCL5/RANTES and CCL2/MCP-1 (p=0.003, <0.0001, 0.033, and 0.033, respectively). Higher levels of IL-6 and IL-8 were found in IU patients with cystoid macular edema (CME) compared to non-CME IU patients (p=0.026 and 0.012, respectively). Significant positive correlations between various observed mediators were present in the AqH of IU patients only.

CONCLUSIONS

Significantly elevated concentrations of multiple intraocular cytokines were found in IU patients, especially IL-6 and IL-8 in those with CME and active disease. In serum elevated TNF-α levels were observed in IU patients. Our findings improve the understanding of the pathogenesis of IU and contribute to the identification of factors which may contribute to the activity of IU.

Polymorphisms of IL23R and Fuchs' syndrome in a Chinese Han population

PURPOSE

The aim of the study was to investigate the association of polymorphisms of the interleukin-23 receptor (IL23R) gene with Fuchs' syndrome in a Chinese Han population.

METHODS

Three single-nucleotide polymorphisms (SNPs), rs7517847, rs11209032 and rs17375018 of IL23R were genotyped in 138 Chinese Han patients with Fuchs' syndrome and 407 healthy controls by using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Data were analyzed by χ(2) analysis.

RESULTS

All genotype and allele distributions in patients with Fuchs' syndrome and healthy controls were in Hardy-Weinberg equilibrium. The frequency of the rs11209032 AA genotype was significantly increased in patients with Fuchs' syndrome as compared to controls (corrected p [pc]=0.036, OR 1.86, 95%CI 1.21 to 2.86). There were no statistically significant differences between patients and healthy controls concerning the other two tested SNPs (rs17375018 and rs7517847). The haplotypes of the tested SNPs were not different between patients and controls. Additionally, analysis according to gender did not show any influence of sex on the association of IL23R with Fuchs' syndrome.

CONCLUSIONS

Our results suggested that the rs11209032 AA genotype of the IL23R gene may predispose for Fuchs' syndrome in Chinese patients.

Aqueous humor neutrophil gelatinase-associated lipocalin levels in patients with idiopathic acute anterior uveitis

PURPOSE

The purpose of this study was to evaluate the levels of neutrophil gelatinase-associated lipocalin (NGAL) in the aqueous humor in eyes with idiopathic acute anterior uveitis (AAU).

METHODS

A comparative control study. Aqueous humor was collected from 20 eyes of 20 patients with idiopathic AAU. The control group included 20 aqueous samples from 20 patients about to undergo cataract surgery and without any other ocular or systemic diseases. The level of NGAL was determined with a commercially available ELISA kit.

RESULTS

The concentration of NGAL in aqueous humor was markedly higher in patients with idiopathic AAU than in control subjects (Mann-Whitney U test, p<0.001). The level of NGAL was 139,197.38+/-183,426.36 (mean+/-SD) pg/ml in eyes with AAU and 3,169.96+/-1,595.78 pg/ml in the eyes of the control group.

CONCLUSIONS

The aqueous humor NGAL level is increased in eyes with idiopathic AAU. These results imply that NGAL is associated with the regulation of inflammation in patients with AAU and could be used as a biomarker of ocular inflammation and immunomodulatory treatment response.

Metabolomic analysis of human vitreous humor differentiates ocular inflammatory disease

PURPOSE

Vitreoretinal disorders lack specific biomarkers that define either disease type or response to treatment. We have used NMR-based metabolomic analysis of human vitreous humor to assess the applicability of this approach to the study of ocular disease.

METHODS

Vitreous samples from patients with a range of vitreoretinal disorders were subjected to high-resolution (1)H-nuclear magnetic resonance spectroscopy (NMR). Good quality spectra were derived from the vitreous samples, and the profiles were analyzed by three different methods.

RESULTS

Principal component analysis (PCA) showed a wide dispersal of the different clinical conditions. Partial least squares discriminant analysis (PLS-DA) was used to define differences between lens-induced uveitis (LIU) and chronic uveitis (CU) and could distinguish between these conditions with a sensitivity of 78% and specificity of 85%. A genetic algorithm coupled with multivariate classification identified a small number of spectral components that showed clear discrimination between LIU and CU samples with sensitivity and specificity >90%. Assignment of specific resonances indicated that some metabolites involved in the arginase pathway were significantly more abundant in LIU than CU.

CONCLUSION

The discrimination we observed based on PCA, PLS-DA, and multivariate variable selection analysis of the NMR spectra suggests that a complex mix of metabolites are present in vitreous fluid of different uveitic conditions as a result of the disease process. Collectively the data demonstrates the efficacy of metabolomic analysis to distinguish between ocular inflammatory diseases.

A suggestive association of fuchs heterochromic cyclitis with cytotoxic T cell antigen 4 gene polymorphism

BACKGROUND

Fuchs heterochromic cyclitis (FHC) is a chronic inflammatory eye disease, usually presenting as unilateral anterior uveitis. Up to date no disease susceptibility genes have been described for FHC.

METHODS

The allele frequency of HLA DRB1 and DQB1, polymorphisms of the tumour necrosis factor (TNF) alpha promoter region (-376, -308, -238), the promoter (-318), first exon (+49) and (AT)n repeat polymorphism of the cytotoxic T cell antigen 4 (CTLA4) gene were analysed in 44 FHC patients and 139 healthy controls.

RESULTS

The CTLA4 -318 C/T genotype was increased in FHC patients [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.4-6.5], as well as long CTLA4 (AT)n microsatellite alleles with more than 16 AT repeats (OR 2.6, 95% CI 1.3-5.3). A trend towards the -308 G/A TNF-alpha genotype was found in the patient cohort, whereas no difference in HLA class II allele distribution was observed.

CONCLUSION

CTLA4 but not TNF-alpha or HLA class II DRB1 and DQB1 may represent a candidate gene for disease susceptibility in FHC.

Ocular complications of childhood rheumatic diseases: uveitis

Ocular involvement is common in pediatric rheumatologic diseases, supporting the concept that these conditions cannot be understood simply as isolated entities, but rather as multisystem disorders. The reasons for the breach of the eye-brain barrier and the targeting of the usually well-shielded eye during a pan-inflammatory process remains unclear. Pediatric rheumatologists should become familiar with these ocular disorders, because as important members of the treatment team, they manage more serious cases of inflammatory eye disease. A close collaboration between the treating rheumatologist and the ophthalmologist is essential to prevent potentially devastating outcomes. Therapeutic interventions such as topical steroids, systemic immunosuppressants, and biologics must balance the necessity of controlling ocular inflammation and the adverse effects of these treatments on a growing child.

Cytokines and chemokines in uveitis: is there a correlation with clinical phenotype?

Uveitis is a general term for intraocular inflammation and includes a large number of clinical phenotypes. As a group of disorders, it is responsible for 10% of all registered blind patients under the age of 65 years. Immune-mediated uveitis may be associated with a systemic disease or may be localized to the eye. The pro-inflammatory cytokines interleukin (IL)-1beta, IL-2, IL-6, interferon-gamma and tumor necrosis factor-alpha have all been detected within the ocular fluids or tissues in the inflamed eye together with others, such as IL-4, IL-5, IL-10 and transforming growth factor-beta. The chemokines IL-8, monocyte chemoattractant protein-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and fractalkine are also thought to be involved in the associated inflammatory response. There have been a number of studies in recent years investigating cytokine profiles in different forms of uveitis with a view to determining what cytokines are important in the inflamed eye. This review attempts to present the current state of knowledge from in vitro and in vivo research on the inflammatory cytokines in intraocular inflammatory diseases.

Update on Fuchs' uveitis syndrome

PURPOSE OF REVIEW

This update aims to summarize the current knowledge on Fuchs' uveitis syndrome and review publications in the last 10 years. Theories on the pathogenesis and etiology of Fuchs' uveitis syndrome are revisited and the management of cataract and glaucoma is updated to reflect recent surgical change.

RECENT FINDINGS

Retrospective reviews have highlighted that patients with Fuchs' uveitis syndrome are often initially misdiagnosed. Studies comparing local inflammatory mediators and cell types have found differences in Fuchs' uveitis syndrome, but the differences in steroid response and degree of inflammation remain poorly understood. Local production of antibodies to rubella has been recently reported in the aqueous of all patients with Fuchs' uveitis syndrome and no controls. Excellent visual outcomes from phacoemulsification have been reported with reduced complications compared with extracapsular cataract extraction.

SUMMARY

Although a single etiological agent and a sensitive laboratory test for the diagnosis of Fuchs' uveitis syndrome is alluring, the diagnosis of Fuchs' uveitis syndrome remains clinical, at least for now. Phacoemulsification has increased the safety of cataract extraction, and the use of intraocular lens is generally safe. The ideal lens material and design are not yet known, but silicone lenses may be best avoided. Glaucoma is often resistant to treatment and should actively be screened for in patients with Fuchs' uveitis syndrome. Medical and surgical treatment for reducing intraocular pressure should be especially aggressive in these patients. Vitrectomy appears to be safe in patients with visually significant vitreous opacification.

Are cytokine gene polymorphisms associated with outcome in patients with idiopathic intermediate uveitis in the United Kingdom?

BACKGROUND/AIM

Competing levels of cytokines, either locally within the eye or systemically, may influence the eventual outcome of ocular inflammation. Polymorphism in the promoter part of the genes controlling cytokine production may result in either higher or lower production of the relevant cytokine to a given stimulus. The authors hypothesised that such polymorphisms may relate to visual outcome in patients with idiopathic intermediate uveitis.

METHODS

DNA was obtained from 125 patients with idiopathic intermediate uveitis and analysed for the interleukin 10 IL-10-1082G/Alpha and IL-10-819C/T, and interferon gamma IFNgamma 874T/A gene polymorphisms. Associations with disease were calculated by both allelic frequency and haplotype analysis, and associations between ocular disease outcomes and the presence of polymorphisms were identified. A bad outcome was defined as loss of vision <6/12 Snellen in both eyes at 5 years from presentation when the eyes were quiet.

RESULTS

An initial screen showed that the 874T allele of the IFNgamma gene was more prevalent in patients than controls (chi2= 7.9; p = 0.004 OR 1.7; 95% CI 1.2 to 2.6 (Pc = 0.02), whereas the IL-10-1082/-819 AT haplotype of the interleukin 10 (IL-10) gene was not. Analysis of disease outcome showed an association between IL-10-1082 AA homozygosity and bad outcome (chi2= 13; p = 0.0003). Moreover, the two cytokine polymorphisms taken together showed that up to 75% of patients with a poor visual outcome had the combined IFNgamma 874TA or TT genotype together with the IL-10-1082AA genotype (chi2= 13.2 p = 0.0008 OR 6.4; 95% CI 1.85 to 23.6 Pc = 0.1).

CONCLUSION

These results show that disease outcome in intermediate uveitis may be partly determined by a complex interplay between cytokine genes and these results may have implications for future treatment with biological agents that target these cytokines.

Increased CD40 ligand in patients with acute anterior uveitis

PURPOSE

The inflammatory response in acute anterior uveitis (AU) is believed to be primarily mediated by autoreactive T-cells. We wanted to evaluate whether the T-cell activation marker CD40 ligand is involved in the AU immunopathogenesis.

METHODS

We evaluated the expression of the CD40 ligand on CD4+ T-cells, CD8+ T-cells and CD19+ B-cells on peripheral blood mononuclear cells using flow cytometry in six patients with unilateral AU, six patients with monosymptomatic optic neuritis (ON) as inflammatory controls, and in six healthy controls. The ex vivo induction of the CD40 ligand on T-cells in patients and controls was also studied.

RESULTS

A significantly higher expression of the CD40 ligand on both CD4+ (p < 0.05) and CD8+ (p < 0.05) T-cells in patients with AU compared to ON patients and healthy controls was found. There was a significantly higher induction of the CD40 ligand on CD8+ T-cells in AU patients compared to ON patients and healthy controls (p < 0.01). No differences in the B-cell population were observed between the three groups.

CONCLUSION

Patients with AU had increased expression of the CD40 ligand on T-cells in the blood and expressed higher levels of the CD40 ligand when stimulated, compared to ophthalmological inflammatory controls and healthy controls. The data suggest that the CD40 ligand is involved in the development of AU.

The development of complications in patients with chronic anterior uveitis

PURPOSE

This study aimed to identify the factors determining the ocular complications and visual outcome in patients with chronic anterior uveitis.

DESIGN

Retrospective, noncomparative case study.

METHODS

Ninety-one eyes of 68 patients with anterior uveitis that lasted longer than 3 months were assessed. Patients were divided into idiopathic and nonidiopathic chronic anterior uveitis and Fuchs' heterochromic uveitis. Visual acuity and complications such as posterior synechiae, cataract formation, raised intraocular pressure (IOP), and posterior segment complications (i.e., cystoid macular edema and optic nerve involvement) were evaluated. Poor visual outcome measured by life-table analysis was considered when logMAR (log of the reciprocal of Snellen visual acuity) visual acuity was 0.3 or worse.

RESULTS

No statistically significant differences in the visual outcome were found between the three groups of patients with chronic anterior uveitis. Posterior synechiae formation was, as expected, significantly increased in patients with chronic anterior uveitis compared with those with Fuchs' heterochromic uveitis. There was a trend for patients with nonidiopathic chronic anterior uveitis to have an increased risk of cystoid macular edema compared with those with idiopathic disease. There were no significant differences in visual outcome between any of the groups with time.

CONCLUSIONS

The visual prognosis for patients with chronic anterior uveitis is generally good. Posterior segment complications appear to be more likely to occur if there is an underlying associated disease. However, the presence of complications does not seem to affect the visual outcome in patients with chronic anterior uveitis.

Intracellular T lymphocyte cytokine profiles in the aqueous humour of patients with uveitis and correlation with clinical phenotype

This study aimed to investigate whether T cells in aqueous humour are different in different types of uveitis and correlate with clinical phenotype. Patients with clinically different types of uveitis, but all displaying active anterior uveitis, were phenotyped and samples of aqueous humour (AH) and peripheral blood (PB) collected. Cells from AH and PB were separated by centrifugation and by density gradient centrifugation (to obtain mononuclear cells PBMC), respectively. Cells were activated with PMA and ionomycin in the presence of Brefeldin A, stained for surface markers and intracellular cytokines, and analysed by flow cytometry. The cytokine profile was correlated with the clinical phenotype. Increased percentages of interleukin (IL)-10+-, but not interferon (IFN)-gamma+ T lymphocytes were found in AH compared with PB in patients with acute anterior uveitis (AAU), FHC or chronic panuveitis (PU). There was a trend towards elevated levels of IL-10+ T cells in AH from patients with FHC compared with AH from acute uveitis and panuveitis patients. Increased levels of IL-10+ T cells in AH compared with PB were also found in samples from patients with isolated uveitis, but not those with associated systemic disease. Levels of cytokine-positive T cells were not associated with the use of topical steroids or to the severity of the anterior uveitis. While type I cytokine-producing T lymphocytes are present in AH during AU, the presence of increased proportions of IL-10+ T lymphocytes in AH from patients with uveitis may be indicative of an anti-inflammatory mechanism that may influence the type and course of ocular inflammation in these patients.

Soluble HLA class I and HLA-DR plasma levels in patients with anterior uveitis

Anterior uveitis (AU) is an autoimmune disease frequently associated with HLA-B27 antigen. Because of the immune regulatory properties of soluble human leukocyte antigen (sHLA) molecules, we quantified sHLA class I (sHLA-I) and sHLA-DR plasma levels in HLA-typed AU patients (n = 60). Randomly selected healthy individuals (n = 128) and HLA-B27 antigen-positive individuals (n = 24) with HLA phenotype frequencies similar to the HLA-B27 antigen-positive AU patients served as control panels. As expected, HLA-B27 phenotype was significantly increased in AU patients (n = 60), compared to healthy controls. Mean sHLA-I levels in AU patients were slightly higher than in randomly selected healthy controls. Regarding AU subgroups, elevated sHLA-I levels were only found in HLA-B27 antigen-negative patients. Compared to controls, sHLA-DR levels were significantly increased in AU patients and the subgroups of HLA-B27 antigen-negative and -positive patients but not Fuchs' heterochromic cyclitis (FHC). AU patients negative for HLA-B27 antigen with a chronic course had higher sHLA-DR levels than those with an acute course. The presence of associated systemic diseases in AU patients was related to elevated sHLA-DR levels. Secretion of sHLA-DR in blood differs among the various forms of AU. Systemic immune activation was present in AU but not in FHC.

The number of CD8+ T cells and NKT cells increases in the aqueous humor of patients with Behçet's uveitis

To determine whether there are differences in the immunopathogenesis of different endogenous uveitis syndromes, the phenotypic characteristics of immune cells were analysed among patients with endogenous uveitis. The aetiology of the uveitis included idiopathic recurrent acute anterior uveitis (18 patients), idiopathic intermediate uveitis (13 patients), Behçet's uveitis (17 patients), Vogt-Koyanagi-Harada syndrome (7 patients), and so on. Flow cytometric analysis was performed using immune cells of the aqueous humor and the peripheral blood during the active phase of intraocular inflammation, and monoclonal antibodies to CD3, CD4, CD8, CD14, CD19, CD56, TCR gammadelta, pan TCR alphabeta and Valpha24. CD8+ T cells were predominant in the aqueous humor of the patients with Behçet's uveitis, whereas CD4+ T cells were mainly found in the aqueous humor of patients other than those with Behçet's uveitis. The number of NKT (CD3+CD56+) cells was significantly higher both in the aqueous humor and the peripheral blood of the patients with Behçet's uveitis compared with the other groups (P < 0.05). CD8+CD56+ cells were the predominant subtype of the increased NKT cells in patients with Behçet's uveitis. In addition, intraocular infiltration of CD14+ cells significantly differed among the uveitis patients (P < 0.05). These results suggest that the immunopathogenesis of endogenous uveitis can vary between syndromes, and that CD8+CD56+ NKT cells may play an important role in the immunopathogenesis of Behçet's uveitis.

Fuchs heterochromic cyclitis: rubella virus antibodies and genome in aqueous humor

PURPOSE

To characterize the polyspecific intraocular antibody synthesis in aqueous humor of patients with chronic inflammatory diseases of the eye and to detect the causative antigen in Fuchs heterochromic cyclitis (FHC).

DESIGN

Retrospective case-control study.

METHODS

Intraocular antibody synthesis is detected in aqueous humor with the Antibody Index [AI] (improved Goldmann-Witmer Index) and quantified as specific antibody fraction, F(s) (intraocular specific antibody concentration in percent of intraocular total immunoglobulin G in aqueous humor). Virus detection is by nested polymerase chain reaction.

RESULTS

Fifty-two eyes of 52 patients with clinically defined FHC (aged 16-73 years) had an intraocular synthesis of rubella antibodies (AI > or =1.5). The rubella genome was detected in 5 (18%) of 28 aqueous humor samples investigated, or in 5 (56%) of 9 patients aged <40 years. Oligoclonal IgG was synthesized in 34 (87%) of 39 eyes. Unaffected fellow eyes (n = 3) or cerebrospinal fluid (n = 2) were normal. In FHC the median rubella AI = 20.6 (total range 1.5-309) was seven times higher than in multiple sclerosis (MS) patients (n = 15) with uveitis intermedia or periphlebitis retinae. In MS the intraocular rubella antibody synthesis (frequency 73%) is part of a polyspecific immune response (increased measles AI in 80%, varicella zoster virus AI in 47%, herpes simplex virus AI in 23%). The median rubella-F(s) = 2.6% in FHC (range = 0.14%-45.9%) was approximately 40 times higher than in MS, consistent with a virus-driven antibody response in FHC. Noninflammatory controls (50 senile cataracts) had neither an intraocular rubella antibody synthesis (normal AI < or =1.4) nor rubella antigen in aqueous humor. The rubella AI was normal in all patients with an intraocular toxoplasmosis (n = 24), anterior uveitis (n = 27), herpes simplex virus iritis (n = 25), and varicella zoster virus iritis (n = 14).

CONCLUSIONS

Fuchs heterochromic cyclitis is a rubella virus-driven disease with persistence of the virus preferentially detected in the younger patients. The proposed laboratory supported diagnosis of FHC is based on the increased rubella Antibody Index. The virus etiology gives a rationale for omitting the ineffective corticosteroid therapy of FHC.

Chemokine receptors and early activation markers in acute anterior uveitis

PURPOSE

To study the peripheral expression of chemokine receptors and early activation markers in acute anterior uveitis (AU).

METHODS

The expression of chemokine receptors CCR1, CCR2, CCR3, CCR5 and CXCR3, and activation markers CD25 (IL2R-alpha-chain), CD122 (IL2R-beta-chain) and CD69 were studied on peripheral blood mononuclear cells using flow cytometry in 10 patients with acute anterior uveitis and in 10 healthy controls.

RESULTS

We found a highly significant up-regulation of CCR5 (p < 0.001) on CD4+ T-cells in the blood of patients with AU compared to in healthy controls. CD69 was significantly higher on both CD4+ and CD8+ T-cells (p < 0.05 and p < 0.001, respectively). We also found a significantly higher expression of CD25 expressing CD4+ T-cells in patients with anterior uveitis (p < 0.05). This expression was directly correlated to the severity of disease (rho = 0.720, p < 0.05).

CONCLUSION

Our data show that patients with acute anterior uveitis have a specific systemic immune activation.

Combined cyclosporin-A /prednisone therapy of patients with active uveitis suppresses IFN-gamma production and the function of dendritic cells

In this study, we assessed the Th1/Th2 polarization of the immune response and the involvement of dendritic cells (DC) and Th1 lymphocytes in the pathogenesis of uveitis. Thirty-seven patients with chronic idiopathic uveitis were enrolled: 21 of them had active uveitis and the remaining 16 were in complete remission. Patients with active uveitis were characterized as follows: 5 had intermediate uveitis, 5 panuveitis and the remaining 11 posterior uveitis. Thirteen healthy subjects were also studied as controls. Patients with active uveitis were treated with cyclosporin-A (CsA) associated to low doses of prednisone (PDS) and studied at baseline and after 6 months of therapy. Analysis of cytokine-producing CD3+ lymphocytes revealed a strong Th1 polarization of the immune response in patients with active uveitis. Th1 lymphocytes paralleled serum IL-12 levels and the response to therapy, which greatly reduced both IFN-gamma+/CD3+ lymphocytes and serum IL-12 levels, associated with a general clinical improvement. In vitro studies demonstrated that DC from untreated patients with active uveitis were mature and functionally active. In fact, they showed a higher ability to stimulate cell proliferation of allogeneic T cells in primary mixed lymphocyte reaction (MLR) and produced larger amounts of IL-12 than DC from CsA/PDS-treated patients and those in remission. These results demonstrate that CsA/PDS therapy impairs the capacity of mature DC to secrete IL-12 and inhibits their MLR activity.

The effect of pars plana vitrectomy in the management of Fuchs heterochromic cyclitis

PURPOSE

Fuchs heterochromic cyclitis (FHC) is characterized by a unilateral chronic iridocyclitis of insidious onset and uncertain cause. Our aim was to evaluate the effect of vitreous surgery in patients with FHC and clinically significant visual symptoms caused by inflammatory vitreous debris.

METHODS

This study was a review of 12 eyes of 12 consecutive patients with FHC who underwent pars plana vitrectomy for visually significant vitreous opacities. Cataract extraction with posterior chamber lens implantation had been performed on four eyes preoperatively. Four eyes had a concomitant lensectomy for cataracts, and one had a surgical posterior capsulotomy. Visual and anatomic data were recorded before surgery and for at least 6 months after surgery.

RESULTS

Visual acuity improved in all patients from an average logMAR of 0.57 to 0.007 (P = 0.0004) and by more than 2 Snellen lines in 8 of 12 of the eyes (P < 0.05). Symptoms of floaters resolved in all 11 patients in whom they were a symptom. Vitreous haze was cleared completely from an average Nussenblatt grade of 1.7 to 0 after 1 week (P = 0.0001).

CONCLUSIONS

Pars plana vitrectomy is a safe and effective treatment for the visual symptoms associated with FHC and can be combined safely with a lensectomy if required.

Uveitis: what do we know and how does it help?

Uveitis essentially means intraocular inflammation and encompasses a wide variety of different disorders. This includes both mild and severe types of inflammation affecting different parts of the eye. Histologically, all uveitis is characterized by an influx of lymphocytes into the affected tissue. In all types these lymphocytes are predominantly of the CD4 type, whether the disorder is mild or blinding, giving no clue as to why. New studies comparing cells in ocular fluids taken from inflamed eyes with different types of inflammation have, for the first time, shown a difference in the cytokine profile, so that in visually benign disease interleukin 10 levels are higher than in those which are blinding.The potential for this in terms of therapy is discussed.

Keratoconus and Fuchs' heterochromic iridocyclitis: a coincidence or a defect during embryogenesis?

PURPOSE

We aimed to discuss the possible role of developmental embryologic factors in neural crest cells in the aetiology of keratoconus and Fuchs' heterochromic iridocyclitis by presenting this case.

CASE REPORT

We diagnosed bilateral keratoconus and unilateral Fuchs' heterochromic iridocyclitis in a 19 year old women complaining of progressively blurring vision in her left eye. We also examined most of her first and second degree relatives. One niece had FHI in addition to a choroidal nevus in the inferior temporal quadrant of her left eye.

DISCUSSION

Regarding the common embryological origins of iris stroma, uveal melanocytes and corneal stroma, it might be worth considering that the combination of FHI and keratoconus is not coincidental. A role of embryologic factors in neural crest cells in the etiology of both diseases cannot be excluded.

Molecular analysis of resolving immune responses in uveitis

To identify the cellular immune processes underlying intra-ocular inflammation, aqueous humour was obtained at cataract surgery from 22 patients with clinically inactive uveitis and 24 patients with age-related cataract. mRNA expression for the cytokines IL-1beta, IL-2, IL-4, IL-6, IL-10, IL-12, interferon-gamma (IFN-gamma), transforming growth factor-beta (TGF-beta); T cell subsets CD3, CD4, CD8; monocytes and macrophages (CD14); and B cells (CD19) was measured using reverse transcriptase-polymerase chain reaction (RT-PCR) and radiometric analysis. The majority of uveitis patients demonstrated a T cell-mediated inflammatory response, predominately involving a Th1-like cytokine profile with expression of IL-2 and IFN-gamma in 16/22 and 18/22 samples, respectively. These cytokines were present in only a small number of patients with age-related cataract. This Th1-like polarization was supported by an increased expression of CD8 in a number of patients. IL-1beta was expressed in only six uveitic eyes. Only four patients expressed either IL-4 or IL-10 and no patient expressed both. TGF-beta mRNA could be detected in 18/22 uveitis patients and 15/24 controls. IL-12, the paradigmatic Th1-inducing cytokine, was absent in all samples but CD14 was expressed in the majority of patients and controls. CD19 could not be detected in any sample. The cellular infiltrate in the uveitic eyes showed clear evidence of low IL-1 and absent IL-12 expression despite a Th1-like profile and high expression of macrophages. This strongly suggests that the systemic immunosuppressive therapy used prior to surgery in some patients and/or the chronicity of the uveitis had actively suppressed/switched off macrophage function, leading to resolution of T cell activity.

Cytokine production and mRNA expression by conjunctival T-cell lines in chronic allergic eye disease

BACKGROUND

Activated CD4+ T cells, mast cells and eosinophils are the main cytokine-producing cell-types infiltrating the conjunctiva during chronic allergic eye diseases. Interactions between these cells are thought to play an important immunopathogenic role in these disorders (giant papillary conjunctivitis; vernal keratoconjunctivitis; atopic keratoconjunctivitis).

OBJECTIVE

The objective was to compare the cytokine profiles of conjunctival T-cell lines from patients with different forms of chronic allergic eye disease.

METHODS

T cells were isolated from conjunctival biopsies and non-specifically expanded into lines. The lines were immunophenotyped by flow cytometry. Cytokine production was quantified by immunoassays and more sensitive molecular techniques were used to investigate cytokine mRNA expression to identify the presence of interleukin (IL) -2, IL-4 and interferon (IFN) -gamma transcripts.

RESULTS

Following four to six rounds of stimulation, the conjunctival T-cell populations were CD3+ (> 93%), with variable levels of CD4 and CD8 expression. All were HLA-DR+ (> 80%) with some HLA-DQ expression. Conjunctival T-cell lines from atopic keratoconjunctivitis produced selective increases in IFN-gamma, IL-10 and IL-13 (P<0.01), those from vernal keratoconjunctivitis produced increased IL-5 (P<0.01) whereas T-cell lines from giant papillary conjunctivitis produced only low levels of cytokines. IL-4 was only detected at the mRNA level and was expressed in four out of five T-cell lines in the vernal keratoconjunctivitis group. In contrast there was moderate to strong expression of IFN-gamma in five out of six T-cell lines in atopic keratoconjunctivitis.

CONCLUSION

Different patterns of T-cell cytokine profiles were observed for each disease, with low-level, non-polarized cytokine production in giant papillary conjunctivitis, a TH2-like profile in vernal keratoconjunctivitis and a shift towards a TH1-like profile in atopic keratoconjunctivitis.