Richard W J Lee

Mycophenolate mofetil for the treatment of uveitis.

PURPOSEnTo evaluate the efficacy and tolerance of mycophenolate mofetil (MMF) for the treatment of noninfectious uveitis using the methods of analysis advocated by the Standardization of Uveitis Nomenclature (SUN) Working Group, and to compare this with other SUN-compliant reports of immunosuppression in ocular inflammation.nnnDESIGNnRetrospective case series. MEDHODS: A predefined data set was retrospectively obtained from the case notes of 100 consecutive uveitis patients treated with MMF at a single academic referral center between April 1, 2000 and August 1, 2006. These data were then analyzed in accordance with SUN recommendations. The main outcome measures were: 1) rate of tapering oral prednisone to 10 mg daily, 2) requirement for alternative second-line immunosuppressive therapy, and 3) rate of MMF dose discontinuation because of side effects.nnnRESULTSnIn this large cohort with noninfectious persistent, chronic, or recurrent uveitis, there was an 84.6% probability of achieving a prednisone dose of < or =10 mg daily after one year of MMF treatment. Alternative second-line immunosuppressive therapy was introduced at a rate of 0.18 per patient-year (PY) and MMF was discontinued because of intolerance at a rate of 0.09/PY, predominantly because of gastrointestinal upset. This corroborates the findings of the only previous SUN-compliant study of MMF in ocular inflammation and is comparable to the rates of treatment success and intolerance we have recently reported for tacrolimus.nnnCONCLUSIONnThis data generates concordant evidence with other SUN-compliant studies supporting the use of MMF in uveitis.

Multicenter study of intravitreal dexamethasone implant in noninfectious uveitis: indications, outcomes, and reinjection frequency.

PURPOSEnTo identify clinical outcomes and treatment patterns of intravitreal dexamethasone implant (Ozurdex; Allergan, Inc) in noninfectious uveitis in the clinical setting.nnnDESIGNnMulticenter retrospective cohort study.nnnMETHODSnEighty-two eyes (63 patients) receiving 142 implant injections over 35 months were included. Treatment indication, uveitis diagnosis, visual acuity, intraocular pressure, vitreous haze score, central retinal thickness by optical coherence tomography, phakic status, number of injections, time to reinjection, systemic treatments, and complications data were collected. Time to visual acuity and vitreous haze score improvement as per the Standardization of Uveitis Nomenclature guidelines were also determined.nnnRESULTSnThe probability of visual acuity improvement (≥0.3 logarithm of the minimal angle of resolution units improvement) was 39% at 1 month, 49% at 3 months, 52% at 6 months, and 58% at 12 months. Eyes with baseline vitritis (vitreous haze score ≥+0.5, n = 45) had a probability of vitreous haze score improvement (2-step decrease or change from +0.5 to 0) at 2 weeks of 41%, at 1 month 63%, at 3 months 73%, at 6 months 79%, and at 12 months 88%. In eyes that completed 12-month follow-up (n = 54), 40.7% underwent 2 injections (mean time to second injection of 6.6 ± 1.9 months) and 11.2% required ≥3 injections (mean time to third injection of 11 ± 1.5 months).nnnCONCLUSIONSnDexamethasone implant use in uveitis provides favorable visual acuity and vitreous haze score outcomes but requires repeated injections, an important consideration when choosing intraocular treatment as a route to controlling uveitis.

Clinical review: Anti-TNFalpha therapies in uveitis: perspective on 5 years of clinical experience

Despite a lack of robust evidence, anti-TNF therapies are in wide use for the treatment of noninfectious ocular inflammatory diseases. There is a clear rationale, based on mechanistic and preclinical efficacy data, for their use in posterior segment intraocular inflammation. However, their increasing use for other indications has been largely extrapolated from the benefit observed in autoinflammatory and autoimmune systemic diseases. Given their cost and the potential for significant adverse events, this review highlights the evidence for their continued use, possibilities for switching anti-TNF agents, and ways of reducing the risk of therapy.

The Effects of Cytokines on Suppression of Lymphocyte Proliferation by Dexamethasone

Treatment failure occurs in up to 30% of patients treated with steroids for inflammatory diseases. The aim of this study was to explore the potential role of 21 cytokines in steroid-resistant inflammatory disease and to develop methods to restore steroid sensitivity through cytokine manipulation. The dexamethasone inhibition of lymphocyte proliferation assay correlates with the outcome of steroid therapy in ulcerative colitis (UC) and other inflammatory diseases. Using this assay, PBMC production of 21 cytokines, assayed by cytokine bead array, was correlated with percentage of suppression of proliferation by 10−6 M dexamethasone (Imax) in 26 healthy volunteers. Effects of the addition of exogenous cytokines to induce steroid resistance in PBMCs from healthy volunteers and cytokine blockade to improve steroid sensitivity in PBMCs from patients with steroid-resistant UC were then explored. Production of IL-1α, IL-10, IL-17, IFN-γ, G-CSF, GM-CSF, TNF-α, and IFN-inducible protein 10 (IP-10) correlated significantly with in vitro steroid sensitivity; however, only IL-2 and TNF-α reduced steroid sensitivity when added exogenously. Addition of IL-10 enhanced steroid suppression. Immunoneutralization or receptor blockade of IL-2, but not TNF-α, IFN-γ, IL-4, IL-17, or IP-10 increased steroid sensitivity in cells from steroid-resistant UC patients. Neutralization of IL-10 reduced steroid sensitivity. Of the large panel of cytokines studied, IL-2 appears to have the greatest antagonistic effect on the antiproliferative effect of steroids. These data suggest that IL-2 inhibition in vivo may improve the response to steroids in steroid-resistant individuals.

Autoimmune and autoinflammatory mechanisms in uveitis

The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8+ T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders.

Current concepts and future directions in the pathogenesis and treatment of non-infectious intraocular inflammation

The blockbuster drug paradigm is under increasing scrutiny across the biopharmaceutical industry. Intraocular inflammation poses particular challenges to this, given the heterogeneity of conditions in the uveitis spectrum, and the increasing acknowledgement of individual patient and disease variance in underlying immune responses. This need has triggered a drive towards personalised and stratified medicine, supported and enabled as a result of continued development of both experimental models and molecular biological techniques and improved clinical classification. As such we have the ability now to systematically appraise at a genomic, transcriptomic, and proteomic level individual immunophenotype, and the promise that in the eye this can be augmented by in vivo immune imaging to identify individual immunopathology. With such advances all running in parallel, we are entering an era of experimental medicine that will facilitate early diagnosis, generate biomarkers for accurate prognostication, and enable the development of individualised and targeted therapies, which can progress rapidly into clinical practice.

Quantitative Analysis of Peripheral Vasculitis, Ischemia, and Vascular Leakage in Uveitis Using Ultra-Widefield Fluorescein Angiography

PURPOSEnTo investigate the relationships between peripheral vasculitis, ischemia, and vascular leakage in uveitis using ultra-widefield fluorescein angiography (FA).nnnDESIGNnCross-sectional, consecutive case series.nnnMETHODSnConsecutive ultra-widefield FA images were collected from 82 uveitis patients (82 eyes) in a single center. The extent of peripheral vasculitis, capillary nonperfusion, and vessel leakage were quantified. Parameters included: (1) foveal avascular zone area and macular leakage, (2) peripheral diffuse capillary leakage and ischemia, (3) peripheral vasculitis, and (4) leakage from neovascularization. Central macular thickness measurements were derived with optical coherence tomography. Main outcome measures were correlations between central and peripheral fluorangiographic changes as well as associations between visual function, ultra-widefield FA-derived metrics, and central macular thickness.nnnRESULTSnAlthough central leakage was associated with peripheral leakage (rxa0= 0.553, Pxa0= .001), there was no association between foveal avascular zone size and peripheral ischemia (rxa0= 0.114, Pxa0= .324), regardless of the underlying uveitic diagnosis. Peripheral ischemia was, however, correlated to neovascularization-related leakage (rxa0= 0.462, Pxa0= .001) and focal vasculitis (rxa0= 0.441, Pxa0= .001). Stepwise multiple regression analysis revealed that a poor visual acuity was independently associated with foveal avascular zone size and central macular thickness (R(2)-adjustedxa0= 0.45, Pxa0= .001).nnnCONCLUSIONSnWe present a large cohort of patients with uveitis imaged with ultra-widefield FA and further describe novel methods for quantification of peripheral vascular pathology, in an attempt to identify visually significant parameters. Although we observed that relationships exist between peripheral vessel leakage, vasculitis, and ischemia, it was only macular ischemia and increased macular thickness that were independently associated with a reduced visual acuity.

CD4+CD25int T Cells in Inflammatory Diseases Refractory to Treatment with Glucocorticoids

Up to 30% of patients with autoimmune, allergic, and lymphoproliferative diseases are refractory to glucocorticoid therapy. The present study was undertaken to investigate whether such steroid resistance (SR) is limited to a subpopulation of CD4+ T cells and, as IL-2 is a putative driver of SR, whether T cell SR is associated with CD25 expression. We show that SR patients have a characteristic subgroup of activated CD4+ T cells that continue to proliferate despite exposure to high-dose Dexamethasone (Dex), demonstrate that CD4+CD25− cells are exquisitely sensitive to Dex whereas CD4+CD25int cells are highly SR, and further find that the combination of an anti-CD25 mAb with Dex enhances suppression of T cell proliferation compared with each agent alone. We therefore conclude that SR is not a general property of all lymphocytes but resides in T cell subpopulations, which are prevalent in SR patients and express intermediary levels of CD25. As a result, we propose a new paradigm for SR disease in which glucocorticoid therapy positively selects SR cells, generating a population of drug-resistant lymphocytes that perpetuate on-going inflammation.

Treat early and embrace the evidence in favour of anti-TNF-α therapy for Behçet's uveitis

How long must patients wait for us to exploit science to their advantage and turn evidence into practice? In this issue, Yamada et al (see page 282) provide crucial evidence in support of anti-tumour necrosis factor (TNF)-α therapy for the treatment of Behcet associated uveitis.1 The potential benefits of this class of drug have been long realised, but healthcare providers have rightly asked the question: are these expensive biologicals really any better than conventional treatment, and does their use put patients at unnecessary risk? At least for the former, it is increasingly evident that the answer is ‘yes.’nnThe journey from the laboratory bench to the clinic has been slower than would even normally be predicted for moving therapies into man. Experimental models of uveitis have provided abundant evidence of TNF-αs pivotal role in mediating retinal tissue destruction,2 and it is now 13u2005years since initial reports confirmed the benefits of TNF-α inhibition in minimising the severity of experimental autoimmune uveoretinitis.3 At that time, similar findings in other organ-specific autoimmune diseases had already ushered in a new era of hope for patients with conditions ranging from rheumatoid arthritis to Crohn disease.4 5 However, in ophthalmology, we are still struggling to realise the full benefit of TNF-α blockade, perhaps reflecting our reluctance as a specialty to embrace developments in systemic therapies for ocular disease.nnTo their credit, the Japanese have taken the …

Consensus on the Diagnosis and Management of Nonparaneoplastic Autoimmune Retinopathy Using a Modified Delphi Approach

PURPOSEnTo develop diagnostic criteria for nonparaneoplastic autoimmune retinopathy (AIR) through expert panel consensus and to examine treatment patterns among clinical experts.nnnDESIGNnModified Delphi process.nnnMETHODSnA survey of uveitis specialists in the American Uveitis Society, a face-to-face meeting (AIR Workshop) held at the National Eye Institute, and 2 iterations of expert panel surveys were used in a modified Delphi process. The expert panel consisted of 17 experts, including uveitis specialists and researchers with expertise in antiretinal antibody detection. Supermajority consensus was used and defined as 75% of experts in agreement.nnnRESULTSnThere was unanimous agreement among experts regarding the categorization of autoimmune retinopathies as nonparaneoplastic and paraneoplastic, including cancer-associated retinopathy and melanoma-associated retinopathy. Diagnostic criteria and tests essential to the diagnosis of nonparaneoplastic AIR and multiple supportive criteria reached consensus. For treatment, experts agreed that corticosteroids and conventional immunosuppressives should be used (prescribed) as first- or second-line treatments, though a consensus agreed that biologics and intravenous immunoglobulin were considered appropriate in the treatment of nonparaneoplastic AIR patients regardless of the stage of disease. Experts agreed that more evidence is needed to treat nonparaneoplastic AIR patients with long-term immunomodulatory therapy and that there is enough equipoise to justify randomized, placebo-controlled trials to determine if nonparaneoplastic AIR patients should be treated with long-term immunomodulatory therapy. Regarding antiretinal antibody detection, consensus agreed that a standardized assay system is needed to detect serum antiretinal antibodies. Consensus agreed that an ideal assay should have a 2-tier design and that Western blot and immunohistochemistry should be the methods used to identify antiretinal antibodies.nnnCONCLUSIONSnConsensus was achieved using a modified Delphi process to develop diagnostic criteria for nonparaneoplastic AIR. There is enough equipoise to justify randomized, placebo-controlled trials to determine whether patients with nonparaneoplastic AIR should be treated with long-term immunomodulatory therapy. Efforts to develop a standardized 2-tier assay system for the detection of antiretinal antibodies have been initiated as a result of this study.