Distinct cytokine and chemokine profiles in the aqueous of patients with uveitis and cystoid macular edema

Ocular cytokinome is linked to clinical characteristics in ocular toxoplasmosis

PURPOSE

To determine the cytokine levels in aqueous humor (AH) of Colombian patients with active ocular toxoplasmosis (OT), and to correlate them with their clinical characteristics.

METHODS

27 Cytokines/chemokines were assayed in 15 AH samples (nine patients with diagnosis of OT biologically-confirmed and six controls that underwent cataract surgery). Correlations were assessed between cytokine/chemokine levels, type of inflammatory response (Th1, Th2, Th17, Treg), and clinical characteristics.

RESULTS

Th2 predominant response was related to more severe clinical features. The presence of VEGF and IL-5 was related to higher number of recurrences. Growth factors (VEGF, FGF, PDGF-β), were related to higher number of lesions. Patients infected by type-I/III strains had a particular intraocular cytokine-pattern.

CONCLUSIONS

Th2 response was related to more severe clinical characteristics in patients infected by Type I/III strains. IL-5 and VEGF were associated with recurrences. We correlate for the first time, specific cytokine-patterns with clinical characteristics and with the infecting Toxoplasma strain.

A pilot study of intravitreal diclofenac versus intravitreal triamcinolone for uveitic cystoid macular edema

PURPOSE

To compare the effect of intravitreal diclofenac (IVD) versus intravitreal triamcinolone (IVT) on refractory uveitic cystoid macular edema (CME).

METHODS

In this pilot randomized clinical trial, 15 eyes were randomly assigned to an IVD group, patients (8 eyes) who received a single intravitreal injection of diclofenac (500 μg/0.1 mL), and an IVT group (7 eyes), cases who received a single intravitreal injection of triamcinolone (2 mg). Change in best-corrected VA in logMAR at week 36 was the primary outcome measure. Secondary outcomes included changes in best-corrected visual acuity (BCVA) at 12 and 24 weeks, central macular thickness (CMT), macular leakage, and potential injection-related complications.

RESULTS

In the IVD group, BCVA was more than the baseline values in 4 eyes at 36 weeks; however, within-group analysis disclosed no statistically significant changes in the mean BCVA in this group. Nonetheless, in the IVT group, mean BCVA improved significantly at 12, 24, and 36 weeks compared to the baseline values. It was 0.86 ± 0.37 at baseline and 0.63 ± 0.48, 0.62 ± 0.42, and 0.43 ± 0.49 logMAR at 12, 24, and 36 weeks, respectively. Mean CMT reduction diminished also significantly only in the IVT group. Nevertheless, comparing the mean BCVA and CMT changes, macular leakage, and the occurrence of any injection-related complications, no significant difference was observed between the groups at any of the follow-up visits.

CONCLUSION

This pilot study demonstrated the superiority of IVT over IVD in the treatment of refractory uveitic CME regarding both functional and anatomical outcomes. Further studies are warranted to confirm potential benefit of IVD observed in this study.

Local therapies for inflammatory eye disease in translation: past, present and future

Despite their side-effects and the advent of systemic immunosuppressives and biologics, the use of corticosteroids remains in the management of patients with uveitis, particularly when inflammation is associated with systemic disease or when bilateral ocular disease is present. The use of topical corticosteroids as local therapy for anterior uveitis is well-established, but periocular injections of corticosteroid can also be used to control mild or moderate intraocular inflammation. More recently, intraocular corticosteroids such as triamcinolone and steroid-loaded vitreal inserts and implants have been found to be effective, including in refractory cases. Additional benefits are noted when ocular inflammation is unilateral or asymmetric, when local therapy may preclude the need to increase the systemic medication.

Implants in particular have gained prominence with evidence of efficacy including both dexamethasone and fluocinolone loaded devices. However, an appealing avenue of research lies in the development of non-corticosteroid drugs in order to avoid the side-effects that limit the appeal of injected corticosteroids. Several existing drugs are being assessed, including anti-VEGF compounds such as ranibizumab and bevacizumab, anti-tumour necrosis factor alpha antibodies such as infliximab, as well as older cytotoxic medications such as methotrexate and cyclosporine, with varying degrees of success. Intravitreal sirolimus is currently undergoing phase 3 trials in uveitis and other inflammatory pathways have also been proposed as suitable therapeutic targets. Furthermore, the advent of biotechnology is seeing advances in generation of new therapeutic molecules such as high affinity binding peptides or modified high affinity or bivalent single chain Fab fragments, offering higher specificity and possibility of topical delivery.

Tocilizumab treatment for refractory uveitis-related cystoid macular edema

BACKGROUND

This retrospective study investigated the efficacy of tocilizumab (TCZ), a fully humanized antibody that binds both to soluble and membrane bound IL-6 receptors, for the treatment of uveitis-related cystoid macular edema (CME) refractory to immunomodulatory therapy.

METHODS

Five refractory patients with uveitis-related CME who received TCZ between January and August 2012 were included. All patients received 8 mg/kg TCZ at 4-week intervals. Data regarding patient demographics, use of immunosuppressive drugs, biologic agents or intravitreal therapies prior to TCZ infusions were collected. Main outcome measure was central foveal thickness (CFT) measured by optical coherence tomography at 6 months. Secondary outcome measures were degree of anterior and posterior chamber inflammation (Standardization of Uveitis Nomenclature Working Group criteria) and visual acuity (logarithm of the minimum angle of resolution [log-MAR]) at month 6. Adverse events (AEs) related to TCZ therapy were also assessed.

RESULTS

Eight eyes from five patients (all females) were included. Mean age was 49.4 years (range, 30-68). Mean follow-up was 8.4 months (range, 6-12). Before TCZ, all patients received and failed conventional immunosuppressive therapy and had received at least another biologic agent. Uveitis diagnoses were Birdshot chorioretinopathy (n = 3), juvenile idiopathic arthritis (JIA)-associated uveitis (n = 1), and idiopathic panuveitis (n = 1). Mean evolution of CME was 13.4 years (range, 2-30). Mean baseline CFT (95% confidence interval) was 602 ± 236 μm at baseline, 386 ± 113 μm at month 1 (p = 0.006), 323 ± 103 μm at month 3 (p = 0.026), and 294.5 ± 94.5 μm at month 6 (p = 0.014). Median best-corrected visual acuity (BCVA) improved from 0.66 ± 0.57 at baseline to 0.47 ± 0.62 at month 6 (p = 0.035). After 6 months, an improvement of ≥ 2 lines of BCVA was observed in 50% of eyes (p = 0.028) remained stable in 25% and worsened in none of the patients. Sustained uveitis remission was achieved in all patients. No AEs were reported.

CONCLUSIONS

These data suggest that TCZ is effective for treating CME in otherwise treatment-refractory cases of uveitis.

Effect of intravitreal methotrexate and rituximab on interleukin-10 levels in aqueous humor of treated eyes with vitreoretinal lymphoma

Intraocular cytokines are promising diagnostic biomarkers of vitreoretinal lymphoma. Here, we evaluate the utility of IL-10, IL-6 and IL-10/IL-6 for discriminating lymphoma from uveitis and report the effects of intraocular methotrexate and rituximab on aqueous cytokine levels in eyes with lymphoma. This is a retrospective case series including 10 patients with lymphoma and 7 patients with uveitis. Non-parametric Mann-Whitney analysis was performed to determine statistical significance of difference in interleukin levels between lymphoma and uveitis. Compared to eyes with uveitis, eyes with lymphoma had higher levels of IL-10 (U = 7.0; two-tailed p = 0.004) and IL-10/IL-6 (U = 6.0; two-tailed p = 0.003), whereas IL-6 levels were more elevated, although insignificant, in those patients with uveitis than in lymphoma (U = 15.0; two-tailed p = ns). Using a receiver operating characteristic analysis to identify threshold values diagnostic for lymphoma, optimal sensitivity and specificity improved to 80.0% and 100%, respectively, for IL-10>7.025 pg/ml and 90.0% and 100.0%, respectively, for IL-10/IL-6>0.02718. In patients in whom serial interleukin levels were available, regular intravitreal treatment with methotrexate and rituximab was associated with reduction in IL-10 levels over time. In conclusion, optimal IL-10 and IL-10/IL-6 threshold values are associated with a diagnostic sensitivity ≥80% and specificity of 100%. Therefore, these cytokines may serve as a useful adjunct in the diagnosis of lymphoma. While negative IL-10 and IL-10/IL-6 values do not exclude a diagnosis of lymphoma, elevated levels do appear to be consistent with lymphoma clinically. Moreover, elevated levels of IL-10 in the setting of a clinically quiet eye may point to impending disease recurrence. Lastly, once lymphoma is diagnosed, IL-10 levels can be monitored over time to assess disease activity and therapeutic response.

Treatment of macular edema because of occlusive vasculitis with bevacizumab (avastin): efficacy of three consecutive monthly injections

PURPOSE

To report the efficacy of intravitreal bevacizumab, administered in a series of three monthly injections followed by a period of observation, in the treatment of cystoid macular edema because of occlusive vasculitis.

METHODS

This is a retrospective review of 13 consecutive eyes of 13 patients with cystoid macular edema because of occlusive vasculitis, which had been unresponsive to other medications and were treated with intravitreal bevacizumab (1.25 mg). The evaluation consisted of a complete ophthalmologic examination, including best-corrected visual acuity measurement, ophthalmoscopy, fluorescein angiography, and optical coherence tomography. The eyes received a series of 3 monthly injections followed by a 3-month observation period.

RESULTS

A significant improvement in foveal thickness and visual acuity was obtained after the first injection, which increased after the second and the third injections and was maintained for 1.5 months after the last injection. The 2 parameters returned to the baseline values 3 months after the last treatment. There were no ocular or systemic adverse effects.

CONCLUSION

Intravitreal injection of bevacizumab seems to be well tolerated and is associated with short-term improvement of visual acuity and decreased retinal thickness in patients with cystoid macular edema because of vasculitis that is resistant to conventional therapy.

Review and update of intraocular therapy in noninfectious uveitis

PURPOSE OF REVIEW

To review new clinically relevant data regarding the intraocular treatment of noninfectious uveitis.

RECENT FINDINGS

Triamcinolone acetonide, the most commonly used intravitreal corticosteroid for treatment of uveitis and uveitic macular oedema has a limited duration of action and is associated with a high risk of corticosteroid-induced intraocular pressure (IOP) rise and cataract. Recent advances have led to the development of sustained-release corticosteroid devices using different corticosteroids such as dexamethasone and fluocinolone acetonide. Treatment options for patients who have previously exhibited corticosteroid hypertensive response have also expanded through the use of new noncorticosteroid intravitreal therapeutics such as methotrexate and antivascular endothelial growth factor (anti-VEGF) agents.

SUMMARY

Ozurdex dexamethasone implant appears to have a better safety profile, and a slightly long-lasting effect than triamcinolone acetonide. The Retisert implant allows the release of corticosteroids at a constant rate for 2.5 years, but it requires surgical placement and its use is associated with a very high risk of cataract and requirement for IOP-lowering surgery. For patients who are steroid responders, methotrexate may offer a better alternative to corticosteroid treatment than anti-VEGF agents, but controlled trials are required to confirm this.

Emerging biologics in the treatment of uveitis

The pathogenic mechanisms underlying uveitis syndromes continue to be evaluated using animal models and in the clinical setting. As the complex interactions between ocular immune cells, proinflammatory cytokines, chemokines and cellular adhesion molecules are uncovered, targeted therapies directed against these immune mediators will continue to be developed. Traditional immunosuppressive medications, such as corticosteroids and steroid-sparing immunomodulatory agents, have demonstrated efficacy in the treatment of uveitic syndromes, but side effects and drug toxicities often limit the use of these medications. The biologic agents, a newer class of medications, target specific immune pathways and have demonstrated efficacy in rheumatologic, dermatologic and neurologic conditions. Biologic therapies (e.g., TNF-alpha inhibitors and IL-2 receptor inhibitor) targeting ocular immune cell surface receptors, cytokines and chemokines continue to be developed and have shown promise in the treatment of uveitis and ocular inflammatory diseases. Clinical and basic aspects of monoclonal antibody therapy for uveitis are presented in this review. Additional studies are needed to further evaluate the role of monoclonal antibodies in the therapeutic armamentarium for uveitis.

Inflammatory cytokines in eyes with uveal melanoma and relation with macrophage infiltration

PURPOSE

The presence of an inflammatory phenotype, characterized by an increased expression of HLA antigens and an immunologic infiltrate, carries a bad prognosis in uveal melanoma. This study was conducted to determine whether the aqueous humor (AqH) from eyes with uveal melanoma contains inflammatory cytokines and whether their presence is associated with inflammation.

METHODS

Immediately after enucleation, AqH was obtained from 37 eyes containing uveal melanoma. Samples were stored at -80°C until use. Fifteen different cytokines were measured with a multiplex bead array. Intratumoral macrophages were analyzed by immunohistochemistry and immunofluorescence staining. The presence of specific cytokines was compared with histopathologic, genetic, and clinical tumor characteristics, as well as patient survival.

RESULTS

Several cytokines showed significantly higher expression in the AqH of uveal melanoma-containing eyes than in the AqH of eyes undergoing cataract surgery. MCP-3 was associated with the presence of CD68(+) macrophages. Correlations were found between some cytokine levels and a few known prognostic factors of uveal melanoma, but cytokine levels were not of predictive value for survival.

CONCLUSIONS

Uveal melanoma-containing eyes often carry increased levels of inflammation-related cytokines in their AqH. However, the presence of most specific cytokines was not related to the presence of macrophages, clinical or histopathologic parameters, or prognosis.

Proinflammatory cytokines are involved in the initiation of the abnormal matrix process in pseudoexfoliation syndrome/glaucoma

Pseudoexfoliation (PEX) syndrome, which is an age-related, generalized elastotic matrix process, currently represents the most common identifiable risk factor for open-angle glaucoma. Dysregulated expression of proinflammatory cytokines has been implicated in the initiation of various fibrotic disorders and in the pathophysiology of glaucoma. Here we investigated the presence, expression, regulation, and functional significance of proinflammatory cytokines in eyes with early and late stages of PEX syndrome/glaucoma in comparison with normal and glaucomatous control eyes using multiplex bead analysis, immunoassays, real-time PCR, Western blotting, immunohistochemistry, and cell culture models. Early stages of PEX syndrome were characterized by approximately threefold (P < 0.005) elevated interleukin (IL)-6 and IL-8 levels in the aqueous humor and a concomitant approximately twofold (P < 0.001) increase in mRNA expression levels in anterior segment tissues as compared with controls. In contrast, late stages of PEX syndrome/glaucoma did not differ significantly from controls. IL-6, IL-6 receptor, and phospho-signal transducer and activator of transcription 3 could be mainly localized to walls of iris vessels and to the nonpigmented epithelium of ciliary processes. IL-6 and IL-8 were significantly up-regulated by ciliary epithelial cells in response to hypoxia or oxidative stress in vitro, whereas IL-6, but not IL-8, induced the expression of transforming growth factor-beta1 and elastic fiber proteins. These findings support a role for a stress-induced, spatially, and temporally restricted subclinical inflammation in the onset of the fibrotic matrix process characteristic of PEX syndrome/glaucoma.

Ranibizumab for refractory uveitis-related macular edema

PURPOSE

To evaluate the effect of intravitreal ranibizumab injections (Lucentis; Genentech Inc, South San Francisco, California, USA) on refractory cystoid macular edema (CME) in patients with controlled uveitis who have failed oral and regional corticosteroid treatment, the mainstays of current medical therapy.

DESIGN

Prospective, noncomparative, interventional case series.

METHODS

Seven consecutive patients with controlled uveitis and refractory CME who had failed corticosteroid treatment were studied. One eligible patient chose not to participate and another did not complete follow-up for nonmedical reasons. Intravitreal ranibizumab injections (0.5 mg) were given monthly for 3 months, followed by reinjection as needed. The primary outcome was the mean change in best spectacle-corrected visual acuity (VA) from baseline to 3 months, and the secondary objective was the mean change in central retinal thickness (CRT) on ocular coherence tomography. Six-month outcomes were also assessed.

RESULTS

At 3 months, the mean increase in acuity for the 6 patients who completed follow-up was 13 letters (2.5 lines), and the mean decrease in CRT was 357 mum. Both VA and CRT improved significantly between baseline and 3 months (P = .03 for each). Although most patients required reinjection, this benefit was maintained at 6 months. There were no significant ocular or systemic adverse effects.

CONCLUSIONS

Intravitreal ranibizumab led to an increase in VA and regression of uveitis-associated CME in patients refractory to or intolerant of standard corticosteroid therapy. Further studies of this promising treatment are warranted.

Control of chemokine gradients by the retinal pigment epithelium

PURPOSE

Proinflammatory cytokines in degenerative diseases can lead to the loss of normal physiology and the destruction of surrounding tissues. In the present study, the physiological responses of human fetal retinal pigment epithelia (hfRPE) were examined in vitro after polarized activation of proinflammatory cytokine receptors.

METHODS

Primary cultures of hfRPE were stimulated with an inflammatory cytokine mixture (ICM): interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha, and interferon (IFN)-gamma. Western blot analysis and immunofluorescence were used to determine the expression/localization of the cytokine receptors on hfRPE. Polarized secretion of cytokines was measured. A capacitance probe technique was used to measure transepithelial fluid flow (J(V)) and resistance (R(T)).

RESULTS

IL-1R1 was mainly localized to the apical membrane and TNFR1 to the basal membrane, whereas IFN-gammaR1 was detected on both membranes. Activation by apical ICM induced a significant secretion of angiogenic and angiostatic chemokines, mainly across the hfRPE apical membrane. Addition of the ICM to the basal but not the apical bath significantly increased net fluid absorption (J(V)) across the hfRPE within 20 minutes. Similar increases in J(V) were produced by a 24-hour exposure to ICM, which significantly decreased total R(T).

CONCLUSIONS

Chemokine gradients across the RPE can be altered (1) through an ICM-induced change in polarized chemokine secretion and (2) through an increase in ICM-induced net fluid absorption. In vivo, both of these factors could contribute to the development of chemokine gradients that help mediate the progression of inflammation/angiogenesis at the retina/RPE/choroid complex.

Inflammatory cystoid macular edema

PURPOSE OF REVIEW

The aim of this article is to update our current understanding and management of inflammatory cystoid macular edema.

RECENT FINDINGS

Cystoid macular edema is a common cause of visual loss in uveitis, which occurs predominantly in older patients with chronic uveitis forms and might be heralded by subclinical changes on optic coherence tomography. Cystoid macular edema is emerging as a major cause of visual loss in HIV-infected patients with immune recovery uveitis. Elevated levels of proinflammatory cytokines and vascular endothelial growth factor were found in all types of cystoid macular edema. Treatment with anti-inflammatory and anti-vascular endothelial growth factor drugs is widely applied for all forms of cystoid macular edema and usually has a beneficial, but temporary effect. So far, there are no clear guidelines for the treatment of subclinical cystoid macular edema in uveitis. The effect of vitrectomy in inflammatory cystoid macular edema is not yet clear and might become more important in the future. Recent advances in management include intravitreal drug delivery systems of cystoid macular edema-modifying drugs.

SUMMARY

This review summarizes current thoughts on inflammatory cystoid macular edema focusing on the new, clinically relevant findings. Upcoming data on aqueous constituents in cystoid macular edema and imaging with the new generation of optic coherence tomography offer the hope that a better treatment strategy will soon be established.

The systemic inflammatory response induced by trauma is reflected by multiple phenotypes of blood neutrophils

Secondary morbidity and mortality after trauma are mainly due to a dysfunctional immune system. Severe injury can trigger a systemic inflammatory response, which is characterised by pre-activation or priming of neutrophils in peripheral blood. Signals initiated as result of local tissue damage can further activate these neutrophils leading to post-injury inflammatory complications. Additional trauma caused by surgical intervention can worsen the inflammatory response, thereby increasing the risk of these inflammatory complications. Limiting surgical procedures through damage control principles can reduce the risk of secondary morbidity. Inflammatory complications after injury cannot adequately be predicted using the current anatomical and physiological-based scoring systems. In this review we propose a methodology focussing on the activation state of the systemic inflammatory response with focus on neutrophils to aid in the risk assessment of secondary morbidity after trauma. Neutrophils are essential effector cells during the post-injury systemic inflammatory response. Neutrophils differentially express an array of surface receptors by which the cells can respond and adapt to changing environmental signals. The determination of specific expression profiles of neutrophil receptors can aid in phenotyping and quantifying the systemic inflammatory response. This article reviews the application of these specific signatures of neutrophil receptors as a consequence of severe injury.

Cytokines, chemokines and soluble adhesion molecules in aqueous humor of children with uveitis

Uveitis in childhood is a visual threatening disease with a complication rate of more than 75%. Despite extensive research, the etiology of uveitis is still unclear although the general opinion is now that uveitis is a T-cell mediated disease. The purpose of this study was to investigate the profile of cytokines, chemotactic cytokines (chemokines) and soluble adhesion molecules in the aqueous humor (AqH) of children with uveitis in order to identify the factors that control the immune response in the eye. In this clinical laboratory investigation we analyzed, with a multiplex immunoassay, 16 immune mediators in the AqH of 25 children with uveitis and 6 children without uveitis. Increased levels of interleukin-2 (IL-2), IL-6, IL-10, IL-13, IL-18, interferon-gamma, tumor necrosis factor-alpha, soluble intercellular adhesion molecule-1, RANTES, IL-8 and interferon-inducible 10-kDa protein were found in the AqH of children with uveitis compared with controls. No significant differences were found for IL-1 beta, IL-4, IL-12 p-70, soluble vascular cell adhesion molecule 1 and Eotaxin. Lower levels of IL-10 and IL-8 were found in quiet stage uveitis (surgical) samples compared with active uveitis (diagnostic) samples and in samples of patients treated with methotrexate (MTX) compared with samples of patients not treated with MTX. Lower levels of IL-10 were as well found in samples taken during the first 3 months after the diagnosis of uveitis than samples taken later during the disease process. No significant differences were found between patients treated with or without topical or systemic (perioperative and long term) corticosteroids. In conclusion, in children with uveitis, multiple intraocular cytokines, chemokines and soluble adhesion molecules are increased in the AqH regardless of active or inactive inflammation. Whether the IL-8 and IL-10 levels in AqH of children with uveitis are correlated with uveitis activity, early or late phase of the course of the disease and systemic treatment with MTX needs further investigation in a bigger study population.

The role of chemokines and their receptors in uveitis

T-cell-dependent immunological events are increasingly being regarded as extremely important in the pathogenesis of uveitis. Several studies have also shown that macrophages are major effectors of tissue damage in uveitis. Neutrophils are also thought to play a central role in the pathogenesis of Behçet's disease. Chemokines are a superfamily of 8 to 10-kDa secreted proteins that direct the recruitment of leukocytes to sites of inflammation. The specific biological effects of chemokines are mediated by a family of seven transmembrane-spanning G-protein-coupled receptors. Recent studies of animals and humans suggest that chemokines and their receptors play a key role in leukocyte recruitment into the eye in uveitis. A strategy for blocking chemokines or chemokine receptors could be a new approach for treatment of uveitis.

Inflammatory mediators of uveitis: cytokines and chemokines

PURPOSE OF REVIEW

The study of uveitis has been restricted by the difficulty in obtaining sufficient intraocular material from both human disease and experimental models. Recent developments in cytokine and chemokine detection have overcome many of these problems. This review presents a summary of the technologic advances in this area.

RECENT FINDINGS

Recent advances in cytokine analysis, in particular multiplexed bead immunoassays, have allowed the measurement of an extensive array of cytokines and chemokines from very small sample volumes. This has revolutionized uveitis research, enabling measurement of a large profile of cytokines and chemokines in intraocular fluid, such as aqueous humour. This allows us to recognize complex patterns of cytokines and chemokines from different forms of uveitis and to examine relationships between different molecules.

SUMMARY

The spectrum of proinflammatory cytokines and chemokines known to be implicated in uveitis has increased over recent years. Many of these molecules have also been found in experimental models of disease and may represent attractive therapeutic targets for the future. With recent advances in cytokine detection, an extension of these techniques with a more detailed analysis of different uveitis conditions may provide useful diagnostic and prognostic information for this potentially blinding group of diseases.