Epigenetic regulation of the epithelial mesenchymal transition induced by synergistic action of TNF-α and TGF-ß in retinal pigment epithelial cells.

To clarify the influence of tumor necrosis factor (TNF)-α on fibrotic phenotypes induced by transforming growth factor (TGF)-ß in retinal pigment epithelial cells (RPECs) by epigenetic regulation. Human primary retinal pigment epithelial cells (RPECs including ARPE19) were used in cultures in the presence or absence of TNF-α and/or TGF-ß2. RT2 Profiler™ (Qiagen) was used for PCR Array for fibrosis and epithelial mesenchymal transition (EMT). Microarray analysis by 3D gene DNA chip was outsourced to Toray Industries Inc. Quantification of histone acetyl transferase (HAT)-related and histone deacetylase (HDAC) related gene expression were also analyzed. HDAC and HAT activity was measured using an EpiQuik HDAC and HAT Activity/Inhibition Assay Kit (Epigentek). CD44, MMP-9, HAT, and HDAC in RPECs were analyzed by western blotting. Analysis of expression of the EMT/fibrosis related CD44 and MMP-9 phenotypes induced by TNF-α+TGF-ß2 revealed four alterations in RPECs: 1) abolition of TGF-ß2-induced α-SMA by TNF-α; 2) synergy between TNF-α+TGF-ß2 for induction of CD44 and MMP-9 phenotypes 3) no inhibition of HDAC activity by either TNF-α or TGF-ß2; and 4) significant inhibition of HAT activity by either TNF-α or TGF-ß2, but no synergy. The HDAC activation through HAT inhibition by TNF-α+TGF-ß was counteracted by HDAC inhibitors, leading to the inhibition of EMT/fibrosis. EMT/fibrotic CD44 and MMP-9 phenotypes were epigenetically upregulated by concerted action of TNF-α and TGF-ß in RPECs. The intervention in epigenetic regulation may hold potential in preventing intraocular proliferative diseases.

Immunohistochemical Detection of Propionibacterium acnes in the Retinal Granulomas in Patients with Ocular Sarcoidosis.

The etiology of sarcoidosis is still obscure; however, Mycobacteria and Propionibacterium acnes are considered the most implicated etiological agent for sarcoidosis. To investigate whether P. acnes is an etiological agent for sarcoid uveitis, we analyzed the frequency of P. acnes detected within the biopsied retinas from patients with ocular sarcoidosis by immunohistochemistry with a P. acnes-specific monoclonal antibody (PAB antibody). Eleven patients (12 eyes) with sarcoid uveitis were enrolled in this study. Eight patients with rhegmatogenous retinal detachment, two patients with non-sarcoid uveitis, and two patients with vitreoretinal lymphoma were enrolled as controls. In the sarcoidosis group, granulomas were mainly observed in the inner retinal layer filled with CD4+ cells and CD68+ cells, indicating the Th1 immune response. P. acnes, identified as round bodies that reacted with the PAB antibody, were present in 10/12 samples (83%) from 9/11 patients (82%) with sarcoidosis. These round bodies were scattered within the retinal granulomas mainly in the inner retinal layer. In the control group, no round bodies were detected. Our results suggested that P. acnes could be associated with sarcoid uveitis. We hypothesize that sarcoid granulomas may be formed by a Th1 immune response to P. acnes hematogenously transmitted to the retina.

A study of host corneal endothelial cells after non-Descemet stripping automated endothelial keratoplasty.

PURPOSE: To determine the short-term fate of the host endothelium and Descemet membrane after non-Descemet stripping automated endothelial keratoplasty (nDSAEK). METHODS: Eight unilateral DSAEK (n = 4) or nDSAEK (n = 4) surgeries were performed in the right eyes of 8 rabbits. Corneal transparency and thickness were followed-up by slit-lamp microscopy, and 2 weeks postoperatively, corneas were evaluated by immunohistochemistry and transmission electron microscopy. RESULTS: Corneas remained clear after both DSAEK and nDSAEK. One week after DSAEK, the stroma-to-stroma surgical interface was identifiable as a zone of fibrotic tissue a few microns thick, whereas in the nDSAEK group, the recipient corneal endothelium and Descemet membrane were clearly visible at the graft-host interface. The retained endothelial cells were positive for Na/K-ATPase but assumed a markedly different morphology from healthy endothelial cells, with cell processes extending into the graft stroma or engulfing strands of irregularly dissected grafted stromal tissue where they occasionally appeared to compartmentalize the transplanted matrix and became detached from the underlying Descemet membrane. CONCLUSIONS: Host endothelial cells 2 weeks after nDSAEK express markers of pump function, but appear to be morphologically altered, occasionally detaching from the adjacent Descemet membrane, extending into the graft stroma or engulfing strands of the grafted stroma at the interface. The short-term persistence and subsequent phenotypical alternation of residual endothelial cells, aligned to structural changes to Descemet membrane, might influence graft adherence after nDSAEK.

Epithelial-mesenchymal transition-like phenotypic changes of retinal pigment epithelium induced by TGF-ß are prevented by PPAR-γ agonists.

PURPOSE: Proliferative eye diseases, such as proliferative vitreoretinopathy and proliferative diabetic retinopathy, are caused partly by fibrotic change of retinal pigment epithelial cells (RPECs). The purpose of our study was to examine the effect of the peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist on the fibrotic change of primate RPECs. METHODS: Monkey RPECs (MRPECs) isolated from a cynomolgus monkey eye were subcultured. To induce fibrotic change, MRPECs were cultured with TGF-ß2 (3 ng/mL), and also cultured in the coexistence of TGF-ß2 and the PPAR-γ agonist pioglitazone (30 µM). The phenotype of the cultured MRPECs was evaluated by phase contrast microscopy and immunocytochemical analysis. The phosphorylation of Smad2/Smad3 proteins was examined by Western blot analysis. RESULTS: Primary MRPECs were cultured as a monolayer with a hexagonal cell shape, and positive expression of ZO-1, Na(+)/K(+)-ATPase, and RPE65 was confirmed. Cell morphology and the expression of these markers were maintained in the presence of pioglitazone, whereas the cells were elongated and the expression of these markers was reduced in its absence. Conversely, the expression of phalloidin, α-smooth muscle actin, and fibronectin was reduced in the presence of pioglitazone, whereas it was increased in the absence. Western blot assay demonstrated that phosphorylation of Smad2/Smad3 proteins was suppressed by pioglitazone. CONCLUSIONS: The PPAR-γ agonist pioglitazone inhibited the fibrotic change of primary MRPECs through the suppression of TGF-ß signaling. Pioglitazone might prove to be a clinically applicable and effective pharmaceutic treatment for proliferative eye diseases.

Case of Mycobacterium tuberculosis meningitis: Gram staining as a useful initial diagnostic clue for tuberculous meningitis.

A 32-year-old man was admitted to our hospital because of fever, headache, and loss of consciousness. Four days before admission, he had had difficulty speaking. On the day of admission, his colleague had found him to be unconscious and lying on his back. He was admitted to our hospital. The temperature at the eardrum was 35.2°C. Neurologic evaluation was negative. Computed tomography (CT) scan of the brain showed slight ventricular enlargement bilaterally. An X-ray film of the chest showed no abnormality. On the second hospital day, neck stiffness was noted. The cerebrospinal fluid (CSF) contained 870 white cells/µl, most of which were neutrophils; the glucose level in the CSF was 10 mg/dl, and the protein level was 140 mg/dl. Stained smears of the CSF, including Gram staining and India-ink preparations, disclosed no microorganisms. Capsular antigen tests for several bacteria were negative. Antimicrobial agents were started. However, by changing the microscope focus slightly while viewing Gram stains of the CSF, we could see brightened and Gram-positive bacilli that had been phagocytosed by neutrophils. This finding suggested the presence of Mycobacterium tuberculosis. Ziehl-Neelsen staining of the CSF and gastric juice revealed anti-acid bacilli. Polymerase chain reaction for M. tuberculosis in the gastric juice was positive. This case showed that Gram staining could be useful as an initial adjunct for the diagnosis of tuberculous meningitis, particularly when the CSF shows predominantly neutrocytic pleocytosis, but no other evidence of bacterial meningitis.

Alleviation of seasonal allergic symptoms with superfine beta-1,3-glucan: a randomized study.

BACKGROUND: The incidence of allergic symptoms to cedar pollen has reached epidemic proportions in Japan. Intravenous injection of beta-1,3-glucan in human subjects is known to induce a T(H)1 response, whereas oral uptake does not. OBJECTIVE: It was examined whether orally ingested, superfine dispersed beta-1,3-glucan (SDG), easily absorbed by intestinal mucosa, would alleviate allergic symptoms. METHODS: Allergic patients were orally administrated either SDG (n = 30) or nondispersed beta-1,3-glucan (n = 30), and allergic symptoms were assessed clinically in a double-blind, placebo-controlled randomized study. RESULTS: SDG alleviated ongoing symptoms of Japanese cedar pollen-induced rhinorrhea, sneezing, nasal congestion, and itchy watery eyes, and its oral uptake before symptom onset exhibited preventive effects. Alleviation of allergic symptoms was evident not only for seasonal allergy to cedar pollen but also for perennial allergy. Oral ingestion of beta-1,3-glucan in individuals with allergic tropism could reduce the spontaneous increase in both allergen-specific and total IgE titers. The clinical responses to treatment were well correlated with the capacity of monocytes to bind to beta-1,3-glucan. Although SDG reduced allergic symptoms, the oral uptake of nondispersed beta-1,3-glucan produced no clinical effects, despite the identical amount of beta-1,3-glucan in both preparations. CONCLUSION: We postulate that orally taken beta-1,3-glucan prepared in a form easily absorbed by intestinal mucosa is able to alleviate cedar pollen-induced allergic symptoms. CLINICAL IMPLICATIONS: Orally effective SDG might greatly contribute to the resolution of epidemic medical problems of seasonal cedar pollen-induced allergy.