Publications

2016

Sainz-de-la-Maza M, Molins B, Mesquida M, Llorenç V, Zarranz-Ventura J, Sala-Puigdollers A, Matas J, Adan A, Foster S. Interleukin-22 serum levels are elevated in active scleritis.. Acta Ophthalmol. 2016;
PURPOSE: To evaluate serum cytokine profile from patients with active scleritis in a two-centre prospective case-control study. METHODS: The serum of 20 active scleritis patients not treated with any local, periocular, or systemic immunomodulatory therapy (IMT) was analysed with multiplex assay to determine the levels of 11 cytokines interleukin (IL)-1β, IL-6, IL-2, IFN-γ, IL-10, IL-12p40, IL-13, IL-17A, IL-5, TNF-α, and TNF-β, and with ELISA to determine the levels of TGF-β1, IL-22, and IL-23. Twenty-five age-matched healthy volunteers were used as controls. In a subgroup of 13 patients with active disease, a second serum sample was obtained when the disease was inactive and levels of IL-22 were determined. Serum IL-22 levels from patients with active scleritis were correlated with type of scleritis (non-necrotizing and necrotizing), degree of inflammation (0-4+ :≤2+ and >2+), and associated systemic disease. RESULTS: Serum levels of IL-22 were elevated in active scleritis patients compared to controls (6.41 ± 1.52 pg/ml versus 1.93 ± 0.39 pg/ml, p = 0.012) and significantly decreased after scleritis remission with the use of IMT (p = 0.005). There was no statistical association with scleritis type, degree of inflammation, or associated systemic disease. The serum levels of other cytokines were not significantly different from controls. CONCLUSION: In our study cohort, IL-22 serum levels were significantly elevated in active scleritis patients compared to controls and decreased significantly after remission. Our results suggest that IL-22, a T helper (Th) 17- and Th22- derived cytokine, may play a critical role in the physiopathology of scleritis.
Silpa-Archa S, Oray M, Preble J, Foster CS. Outcome of tocilizumab treatment in refractory ocular inflammatory diseases.. Acta Ophthalmol. 2016;94(6):e400–6.

PURPOSE: To report the outcomes of tocilizumab treatment for refractory ocular inflammatory diseases. METHODS: A retrospective case series of 17 patients (28 eyes) diagnosed with recalcitrant ocular inflammatory diseases including uveitis (10 cases), scleritis (six cases) and orbital pseudotumour (one case), who received tocilizumab between April 2010 and March 2015. All patients were initiated with treatment of 4 mg/kg or 8 mg/kg tocilizumab. The primary outcome was absence of inflammation and achievement of steroid sparing at 6 and 9 months. Secondary outcomes were change in visual acuity and major adverse effects of tocilizumab causing discontinuation of the treatment. RESULTS: Mean age at initiation of tocilizumab was 41 ± 16 years. Prior to tocilizumab treatment, all patients underwent unsuccessful conventional immunosuppressive therapy while 94% of patients (16/17) failed treatment with various biological agents. After tocilizumab administration, control of inflammation and steroid sparing were achieved in 63% and 71% of uveitis patients at 6 and 9 months, while 50% of scleritis patients achieved the primary outcome at 6 and 9 months. Mean duration of tocilizumab therapy was 12.6 ± 10.0 (range, 2-35) months. Three of four patients who had a follow-up of at least 18 (range, 18-35) months experienced quiescent inflammation for up to 32 months of tocilizumab use until last visit. Four patients (24%) discontinued tocilizumab due to serious side effects including neutropenia, unacceptable dizziness and nausea, severe angioedema and severe abdominal pain. CONCLUSION: Our series demonstrated moderate efficacy of tocilizumab in recalcitrant uveitis and scleritis. Serious adverse effects were not uncommon.

Taher M, Nakao S, Zandi S, Melhorn M, Hayes, Hafezi-Moghadam A. Phenotypic transformation of intimal and adventitial lymphatics in atherosclerosis: a regulatory role for soluble VEGF receptor 2.. FASEB J. 2016;30(7):2490–9.

The role of lymphatics in atherosclerosis is not yet understood. Here, we investigate lymphatic growth dynamics and marker expression in atherosclerosis in apolipoprotein E-deficient (apoE(-/-)) mice. The prolymphangiogenic growth factor, VEGF-C, was elevated in atherosclerotic aortic walls. Despite increased VEGF-C, we found that adventitial lymphatics regress during the course of formation of atherosclerosis (P < 0.01). Similar to lymphatic regression, the number of lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1(+)) macrophages decreased in the aortic adventitia of apoE(-/-) mice with atherosclerosis (P < 0.01). Intimal lymphatics in the atherosclerotic lesions exhibited an atypical phenotype, with the expression of podoplanin and VEGF receptor 3 (VEGFR-3) but not of LYVE-1 and prospero homeobox protein 1. In the aortas of atherosclerotic animals, we found markedly increased soluble VEGFR-2. We hypothesized that the elevated soluble VEGFR-2 that was found in the aortas of apoE(-/-) mice with atherosclerosis binds to and diminishes the activity of VEGF-C. This trapping mechanism explains, despite increased VEGF-C in the atherosclerotic aortas, how adventitial lymphatics regress. Lymphatic regression impedes the drainage of lipids, growth factors, inflammatory cytokines, and immune cells. Insufficient lymphatic drainage could thus exacerbate atherosclerosis formation. Our study contributes new insights to previously unknown dynamic changes of adventitial lymphatics. Targeting soluble VEGFR-2 in atherosclerosis may provide a new strategy for the liberation of endogenous VEGF-C and the prevention of lymphatic regression.-Taher, M., Nakao, S., Zandi, S., Melhorn, M. I., Hayes, K. C., Hafezi-Moghadam, A. Phenotypic transformation of intimal and adventitial lymphatics in atherosclerosis: a regulatory role for soluble VEGF receptor 2.

Utheim TP, Islam R, Fostad I, Eidet J, Sehic A, Olstad O, Dartt DA, Messelt E, Griffith M, Pasovic L. Storage Temperature Alters the Expression of Differentiation-Related Genes in Cultured Oral Keratinocytes.. PLoS One. 2016;11(3):e0152526.
PURPOSE: Storage of cultured human oral keratinocytes (HOK) allows for transportation of cultured transplants to eye clinics worldwide. In a previous study, one-week storage of cultured HOK was found to be superior with regard to viability and morphology at 12°C compared to 4°C and 37°C. To understand more of how storage temperature affects cell phenotype, gene expression of HOK before and after storage at 4°C, 12°C, and 37°C was assessed. MATERIALS AND METHODS: Cultured HOK were stored in HEPES- and sodium bicarbonate-buffered Minimum Essential Medium at 4°C, 12°C, and 37°C for one week. Total RNA was isolated and the gene expression profile was determined using DNA microarrays and analyzed with Partek Genomics Suite software and Ingenuity Pathway Analysis. Differentially expressed genes (fold change > 1.5 and P 0.05) were identified by one-way ANOVA. Key genes were validated using qPCR. RESULTS: Gene expression of cultures stored at 4°C and 12°C clustered close to the unstored control cultures. Cultures stored at 37°C displayed substantial change in gene expression compared to the other groups. In comparison with 12°C, 2,981 genes were differentially expressed at 37°C. In contrast, only 67 genes were differentially expressed between the unstored control and the cells stored at 12°C. The 12°C and 37°C culture groups differed most significantly with regard to the expression of differentiation markers. The Hedgehog signaling pathway was significantly downregulated at 37°C compared to 12°C. CONCLUSION: HOK cultures stored at 37°C showed considerably larger changes in gene expression compared to unstored cells than cultured HOK stored at 4°C and 12°C. The changes observed at 37°C consisted of differentiation of the cells towards a squamous epithelium-specific phenotype. Storing cultured ocular surface transplants at 37°C is therefore not recommended. This is particularly interesting as 37°C is the standard incubation temperature used for cell culture.
Joyal JS, Sun Y, Gantner M, Shao Z, Evans L, Saba N, Fredrick T, Burnim S, Kim JS, Patel G, Juan A, Hurst C, Hatton C, Cui Z, Pierce K, Bherer P, Aguilar E, Powner M, Vevis K, Boisvert M, Fu Z, Levy E, Fruttiger M, Packard A, Rezende F, Maranda B, Sapieha P, Chen J, Friedlander M, Clish C, Smith L. Retinal lipid and glucose metabolism dictates angiogenesis through the lipid sensor Ffar1.. Nat Med. 2016;22(4):439–45.

Tissues with high metabolic rates often use lipids, as well as glucose, for energy, conferring a survival advantage during feast and famine. Current dogma suggests that high-energy-consuming photoreceptors depend on glucose. Here we show that the retina also uses fatty acid β-oxidation for energy. Moreover, we identify a lipid sensor, free fatty acid receptor 1 (Ffar1), that curbs glucose uptake when fatty acids are available. Very-low-density lipoprotein receptor (Vldlr), which is present in photoreceptors and is expressed in other tissues with a high metabolic rate, facilitates the uptake of triglyceride-derived fatty acid. In the retinas of Vldlr(-/-) mice with low fatty acid uptake but high circulating lipid levels, we found that Ffar1 suppresses expression of the glucose transporter Glut1. Impaired glucose entry into photoreceptors results in a dual (lipid and glucose) fuel shortage and a reduction in the levels of the Krebs cycle intermediate α-ketoglutarate (α-KG). Low α-KG levels promotes stabilization of hypoxia-induced factor 1a (Hif1a) and secretion of vascular endothelial growth factor A (Vegfa) by starved Vldlr(-/-) photoreceptors, leading to neovascularization. The aberrant vessels in the Vldlr(-/-) retinas, which invade normally avascular photoreceptors, are reminiscent of the vascular defects in retinal angiomatous proliferation, a subset of neovascular age-related macular degeneration (AMD), which is associated with high vitreous VEGFA levels in humans. Dysregulated lipid and glucose photoreceptor energy metabolism may therefore be a driving force in macular telangiectasia, neovascular AMD and other retinal diseases.

Tang S, Hemberg M, Cansizoglu E, Belin S, Kosik K, Kreiman G, Steen H, Steen J. f-divergence cutoff index to simultaneously identify differential expression in the integrated transcriptome and proteome.. Nucleic Acids Res. 2016;44(10):e97.

The ability to integrate 'omics' (i.e. transcriptomics and proteomics) is becoming increasingly important to the understanding of regulatory mechanisms. There are currently no tools available to identify differentially expressed genes (DEGs) across different 'omics' data types or multi-dimensional data including time courses. We present fCI (f-divergence Cut-out Index), a model capable of simultaneously identifying DEGs from continuous and discrete transcriptomic, proteomic and integrated proteogenomic data. We show that fCI can be used across multiple diverse sets of data and can unambiguously find genes that show functional modulation, developmental changes or misregulation. Applying fCI to several proteogenomics datasets, we identified a number of important genes that showed distinctive regulation patterns. The package fCI is available at R Bioconductor and http://software.steenlab.org/fCI/.

Saboo U, Amparo F, Shikari H, Dana R. Prevalence of ocular hypertension and glaucoma in patients with chronic ocular graft-versus-host disease.. Graefes Arch Clin Exp Ophthalmol. 2016;254(5):923–8.

PURPOSE: To evaluate the prevalence of ocular hypertension (OHT) and glaucoma in patients with chronic ocular graft-versus-host disease (GVHD). METHODS: We performed a retrospective chart review of 218 patients diagnosed with chronic ocular GVHD. Ocular hypertension was defined as intraocular pressure (IOP) ≥ 24 mmHg in either eye without any glaucomatous optic disc changes. Glaucoma suspect was defined as optic disc changes with a cup-to-disc ratio ≥ 0.7 in either eye or asymmetry of ≥ 0.3 between the two eyes. Glaucoma was defined by glaucomatous optic disc changes plus glaucomatous visual field defects in two consecutive reliable visual field tests. The number of cases of ocular hypertension, glaucoma, and glaucoma suspects was evaluated. RESULTS: Thirty-three patients (15 %) were diagnosed with OHT, eight patients (3.6 %) with suspicion of glaucoma, and one patient (0.4 %) with glaucoma. OHT occurred within 6 months of developing ocular GVHD in 60 % of the cases and within the first year in 76 %. High IOP normalized in 67 % of patients when the dosage of topical or systemic corticosteroids was lowered, and 27 % of patients required anti-glaucoma therapy. CONCLUSIONS: Ocular hypertension is a common complication in patients with ocular GVHD, with a prevalence of 15 %. The rise in intraocular pressure is often transient and resolves with management of corticosteroids in most cases. However, clinicians should be aware that nearly one-third of the patients with OHT might require anti-glaucoma treatment. The prevalences of glaucoma and suspicion of glaucoma were not higher than in the general population.

PURPOSE: To provide a critical analysis of a series of periocular lobular capillary hemangiomas in adults, outlining characteristic clinical and histopathologic patterns in comparison with those of other vascular tumors of adults and children. DESIGN: Retrospective, observational case series. METHODS: Review of clinical data, hematoxylin and eosin stained sections and immunohistochemical studies of smooth muscle actin (SMA), D2-40, CD34, and glucose transporter 1 (GLUT-1). RESULTS: The 7 female and 4 male patients were diagnosed with periocular lobular capillary hemangioma at a median age of 39 years (range of 17-82 years). The tumors were small (3-14 mm, median size 6 mm) and well-circumscribed, arose over the course of weeks to months and developed most commonly in the canthal region, followed by the upper eyelid skin. The tumors were all composed microscopically of repeating units of various sizes (lobules) consisting of CD34-postive, GLUT-1-negative endothelial cells and SMA-positive pericytes arranged in macro- or micro-lobules. Some foci also exhibited ectatic vessels or diffuse, non-lobular capillary proliferations. Excision was curative without recurrence. CONCLUSION: Although capillary hemangiomas are more common in children, lobular capillary hemangiomas can also arise in the periocular region of adults. Some histopathologic features of these lesions are shared with those of infantile hemangioma and tufted angioma of children, but features of the clinical presentation and the results of immunohistochemical staining patterns are distinctive.

Penman A, Hancock H, Papavasileiou E, James M, Idowu O, Riche D, Fernandez M, Brauner S, Smith S, Hoadley S, Richardson C, Vazquez V, Chi C, Andreoli C, Husain D, Chen C, Sobrin L. Risk Factors for Proliferative Diabetic Retinopathy in African Americans with Type 2 Diabetes.. Ophthalmic Epidemiol. 2016;23(2):88–93.

PURPOSE: To assess personal and demographic risk factors for proliferative diabetic retinopathy in African Americans with type 2 diabetes. METHODS: In this prospective, non-interventional, cross-sectional case-control study, 380 African Americans with type 2 diabetes were enrolled. Participants were recruited prospectively and had to have either: (1) absence of diabetic retinopathy after ≥10 years of type 2 diabetes, or (2) presence of proliferative diabetic retinopathy when enrolled. Dilated, 7-field fundus photographs were graded using the Early Treatment Diabetic Retinopathy Study scale. Covariates including hemoglobin A1C (HbA1C), blood pressure, height, weight and waist circumference were collected prospectively. Multivariate regression models adjusted for age, sex and site were constructed to assess associations between risk factors and proliferative diabetic retinopathy. RESULTS: Proliferative diabetic retinopathy was associated with longer duration of diabetes (odds ratio, OR, 1.62, p < 0.001), higher systolic blood pressure (OR 1.65, p < 0.001) and insulin use (OR 6.65, p < 0.001) in the multivariate regression analysis. HbA1C was associated with proliferative diabetic retinopathy in the univariate analysis (OR 1.31, p = 0.002) but was no longer significant in the multivariate analysis. CONCLUSIONS: In this case-control study of African Americans with type 2 diabetes, duration of diabetes, systolic hypertension and insulin use were strong risk factors for the development of proliferative diabetic retinopathy. Interestingly, HbA1C did not confer additional risk in this cohort.

Restoration of the retinal pigment epithelial (RPE) cells to prevent further loss of vision in patients with age-related macular degeneration represents a promising novel treatment modality. Development of RPE transplants, however, requires up to 3 months of cell differentiation. We explored whether the silk protein sericin can induce maturation of primary human retinal pigment epithelial (hRPE) cells. Microarray analysis demonstrated that sericin up-regulated RPE-associated transcripts (RPE65 and CRALBP). Upstream analysis identified the NF-κB pathway as one of the top sericin-induced regulators. ELISA confirmed that sericin stimulates the main NF-κB pathway. Increased levels of RPE-associated proteins (RPE65 and the pigment melanin) in the sericin-supplemented cultures were confirmed by western blot, spectrophotometry and transmission electron microscopy. Sericin also increased cell density and reduced cell death following serum starvation in culture. Inclusion of NF-κB agonists and antagonists in the culture medium showed that activation of the NF-κB pathway appears to be necessary, but not sufficient, for sericin-induced RPE pigmentation. We conclude that sericin promotes pigmentation of cultured primary hRPE cells by activating the main NF-κB pathway. Sericin's potential role in culture protocols for rapid differentiation of hRPE cells derived from embryonic or induced pluripotent stem cells should be investigated.