Citation: He S, Barron E, Ishikawa K, et al. Inhibition of DNA methylation and methyl-CpG-binding protein 2 suppresses RPE transdifferentiation: relevance to proliferative vitreoretinopathy. Invest Ophthalmol Vis Sci. 2015;56:5579-5589. DOI:10.1167/ iovs.14-16258 PURPOSE. The purpose of this study was to evaluate expression of methyl-CpG-binding protein 2 (MeCP2) in epiretinal membranes from patients with proliferative vitreoretinopathy (PVR) and to investigate effects of inhibition of MeCP2 and DNA methylation on transforming growth factor (TGF)-b-induced retinal pigment epithelial (RPE) cell transdifferentiation. METHODS.Expression of MeCP2 and its colocalization with cytokeratin and a-smooth muscle actin (a-SMA) in surgically excised PVR membranes was studied using immunohistochemistry. The effects of 5-AZA-2 0 -deoxycytidine (5-AZA-dC) on human RPE cell migration and viability were evaluated using a modified Boyden chamber assay and the colorimetric 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Expression of RASAL1 mRNA and its promoter region methylation were evaluated by real-time PCR and methylationspecific PCR. Effects of 5-AZA-dC on expression of a-SMA, fibronectin (FN), and TGF-b receptor 2 (TGF-b R2) and Smad2/3 phosphorylation were analyzed by Western blotting. Effect of short interfering RNA (siRNA) knock-down of MeCP2 on expression of a-SMA and FN induced by TGFb was determined.RESULTS. MeCP2 was abundantly expressed in cells within PVR membranes where it was double labeled with cells positive for cytokeratin and a-SMA. 5-AZA-dC inhibited expression of MeCP2 and suppressed RASAL1 gene methylation while increasing expression of the RASAL1 gene. Treatment with 5-AZA-dC significantly suppressed the expression of a-SMA, FN, TGF-b R2 and phosphorylation of Smad2/3 and inhibited RPE cell migration. TGF-b induced expression of a-SMA, and FN was suppressed by knock-down of MeCP2.CONCLUSIONS. MeCP2 and DNA methylation regulate RPE transdifferentiation and may be involved in the pathogenesis of PVR.

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Purpose. As part of plans to provide help to people in remote and poor areas who have no medical resources, a portable slit-lamp based on a smartphone was proposed. This would help in early screening of cataract diseases. Methods. This means a microlens is designed that would work with a phone’s camera. The phone’s photo taking function is used in capturing the image of the eyes lens to replace the observation system of the desktop slit-lamp. A simplified slit light band was designed. In order for the light source part to meet the portable requirements of the slit-lamp, the adjustable and diffused light functions of the ligaments were removed in this design. Furthermore, the images collected by the smartphone are uploaded to the deep learning cataract screening system, which can achieve real-time and effective screening of cataract. Results. Unlike the desktop slit-lamp, which needs skilled personnel to operate, this device can be easily operated by less-skilled or inexperienced doctors. This eliminates the concerns of inaccurate diagnosis based on the use of unskilled professionals. Due to the portability, ease of use, and simplicity in obtaining crystal images of this device, it serves as a promising platform for nonhospital screening and telemedicine. Conclusions. In this paper, we invented a small portable device for screening cataract. This device is to make screening and diagnosis of cataract in remote areas very fast and effective. It will also solve the problem of inadequate specialized doctors and equipment in those areas as well. Translational Relevance. Smartphones can be used with portable slit-lamps to capture the images of the lens.

Background:Retinal degeneration causes irreversible blindness. Human retinal progenitor cells (hRPCs) have the potential to treat retinal diseases. The vitreous cavity is a relatively immune-privileged site that is suitable for stem cell transplantation in the treatment of retinal diseases. This study aimed to evaluate the therapeutic efficacy and safety of intravitreal injection of hRPCs in retinal degeneration therapy. Material/Methods: hRPCs were primary-cultured and injected into the vitreous cavity of RCS rats. To determine whether hRPCs formed teratomas in immune-deficient mice, hRPCs at different passages were transplanted into BALB/c-nu mice. The visual function was detected by electroretinography recording. Changes in the outer nuclear layer (ONL) were analyzed by histological testing and cell counting. The protective mechanism was further assessed by cytokine antibody array. Results:Intravitreal transplantation of hRPCs maintained retinal function and preserved retinal morphology. Importantly, grafted cells in the vitreous cavity were well tolerated, with no adverse effects. Teratoma was not formed in BALB/c-nu mice after hRPCs transplantation. The number of hRPCs-injected eyes and thickness of ONL in the hRPCs-treated group were higher than those in the untreated group and HBSS injection group. The cytokine antibody array revealed that hRPCs expressed GDF-15, PDGF-AA, EGF, and NT-4. Conclusions:Our findings show that intravitreal injection of hRPCs is effective and safe in protecting photoreceptor cells in RCS rats, but were no longer effective at 12 weeks after transplantation. Moreover, hRPCs released multiple neurotrophic factors that may be involved in treating retinal disease.

T-shaped coil-rod-coil oligomers, consisting of a dibenzo [a,c]phenazine unit and phenyl groups linked together with acetylenyl bonds at the 2,7-position of dibenzo[a,c]phenazine as a rigid segment have been synthesized. The coil segments of these new molecules composed of poly(ethylene oxide) (PEO)-poly(propylene oxide) (PPO) incorporating lateral methyl groups between the rod and coil segment and two flexible alkyl groups connecting with the rigid segment at the 4,6position of dibenzo[a,c]phenazine, respectively. The experimental results reveal that the length of the flexible PEO coil chain influence construction of various supra-nanostructures from lamellar structure to rectangular columnar structure. It is also shown that introduction of different length of alkyl side chain groups in the backbone of the T-shaped molecules affect the self-organization behavior to form hexagonal perforate layer or oblique columnar structures. In addition, lateral methyl groups attached to the surface of rod and coil segments, dramatically influence the self-assembling behavior in the crystalline phase. T-shaped molecules containing a lateral methyl group at the surface of rod and PEO coil segments, self-assemble into 3D body-centered tetragonal structures in the crystalline phase, while molecules without a lateral methyl group based on PEO coil chain self-organize into 2D oblique columnar crystalline structures.