An empty E1−, E3−, E4− adenovirus vector protects photoreceptors from light-induced degeneration

We have previously identified a neuroprotective effect associated with empty (E1−, E3−, E4−) adenovirus vector delivery in a model of light-induced, photoreceptor cell death. In this study, we further characterize this protective effect in light-injured retina and investigate its molecular basis. Dark-adapted BALB/c mice, aged 6–8 weeks, were exposed to standardized, intense fluorescent light for 96 or 144 h. Prior to dark adaptation, all mice received intravitreous injection of 1 × 109 particles of an empty (E1−, E3−, E4−) adenovirus vector in one eye and vehicle in the other. Following light challenge of 96 or 144 h, histopathological analysis and quantitative photoreceptor cell counts were conducted. Semiquantitative assessment of messenger ribonucleic acid (mRNA) for the apoptosis related genes: p50, p65, IkBa, caspase-1, caspase-3, Bad, c-Jun, Bax, Bak, Bcl-2, c-Fos, and p53 using quantitative reverse transcriptase polymerase chain reaction was performed on eyes following 12 h of light exposure. Following 96 h of light exposure, the photoreceptor cell density for E1−, E3−, E4− adenovirus vector and vehicle-injected eyes were 87.5 ± 9.5 and 79.3 ± 10.1, respectively, (p = 0.79). After 144 h of light exposure, the photoreceptor cell density was preserved in vector-injected eyes as compared to vehicle treated eyes, 68.9 ± 10.0 and 49.2 ± 4.6, respectively (p = 0.016). Relative mRNA levels of c-Fos and c-Jun at 12-h light exposure after injection differed significantly between vector- and vehicle-injected eyes (p = 0.036, 0.016, respectively). The expression of the other apoptosis-related genes evaluated was not significantly affected. This study investigates the molecular basis of photoreceptor neuroprotective pathway induction associated with E1−, E3−, E4− adenovirus vectors. The results indicate that empty adenovirus vectors protect photoreceptors from light-induced degeneration by the modulation of apoptotic pathways. Gene expression changes suggest that the suppression of c-Fos and c-Jun upregulation contributes significantly to the neuroprotective effect. Understanding the molecular basis of the neuroprotective pathway induction in photoreceptors is critical to the development of novel therapies for retinal degenerations

Development and preliminary results of bimanual smart micro-surgical system using a ball-lens coupled OCT distance sensor

Bimanual surgery enhances surgical effectiveness and is required to successfully accomplish complex microsurgical tasks. The essential advantage is the ability to simultaneously grasp tissue with one hand to provide counter traction or exposure, while dissecting with the other. Towards enhancing the precision and safety of bimanual microsurgery we present a bimanual SMART micro-surgical system for a preliminary ex-vivo study. To the best of our knowledge, this is the first demonstration of a handheld bimanual microsurgical system. The essential components include a ball-lens coupled common-path swept source optical coherence tomography sensor. This system effectively suppresses asynchronous hand tremor using two PZT motors in feedback control loop and efficiently assists ambidextrous tasks. It allows precise bimanual dissection of biological tissues with a reduction in operating time as compared to the same tasks performed with conventional onehanded approaches. © 2016 Optical Society of America.1

The Question of a Role for Statins in Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the leading cause of irreversible central vision loss in patients over the age of 65 years in industrialized countries. Epidemiologic studies suggest that high dietary fat intake is a risk factor for the development and progression of both vascular and retinal disease. These, and other associations, suggest a hypothesis linking elevated cholesterol and AMD progression. It follows, therefore, that cholesterol-lowering medications, such as statins, may influence the onset and progression of AMD. However, the findings have been inconclusive as to whether statins play a role in AMD. Due to the significant public health implications of a potential inhibitory effect of statins on the onset and progression of AMD, it is important to continually evaluate emerging findings germane to this question

Permanent Keratoprosthesis Combined With Pars Plana Vitrectomy and Silicone Oil Injection for Visual Rehabilitation of Chronic Hypotony and Corneal Opacity

Purpose: To present outcomes of combined pars plana vitrectomy, silicone oil (SO) injection, and permanent keratoprosthesis (Kpro) procedure in prephthisical eyes

Viral Transgene Expression Delivered by Repeat Intraocular Adenoviral Vector Injection: in Vivo Live Imaging Study

We delivered adenovirus vector (Ad) via intravitreous injection and monitored transgene (luciferase) expression in living mice (BALB/c) at multiple time points. In vivo live imaging technology was able to assess dynamically intraocular luciferase expression in a single animal population throughout the entire experiment period. Using this information, we were able to determine the optimal time point for readministration of Ad into the eyes and to dynamically study the time course of expression of a second Ad administration. Optical imaging demonstrated the limited period of transgene expression in eyes. Significant transgene signal was also detected in livers. The repeat intraocular delivery of the adenovirus resulted in significant blunting of transgene expression in both eyes and livers compared to the initial delivery. Periocular corticosteroid (triamcinolone acetonide) injection combined with initial Ad delivery was effective to rescue luciferase expression on repeat Ad vector delivery. However, this effect was not observed when corticosteroid was combined with repeat Ad delivery. Although corticosteroid enhanced ocular transgene expression, it also increased transgene expression in liver, which has potential safety implications. This dynamic transgene expression in eyes was successfully traced and monitored via a live imaging technique

The Role of Indoleamine 2,3-Dioxygenase in Retinal Pigment Epithelial Cell-mediated Immune Modulation

Purpose: To evaluate the role of indoleamine dioxygenase (IDO) in human retinal pigment epithelial cell (RPE)-mediated immune modulation. Methods: The immunosuppression of cultured human RPEs (ARPE-19 cells) was assayed using the mixed lymphocyte reaction (MLR) harvested from CBA/J and BALB/c mice. The expression of critical immune modulatory molecules, such as class II major histocompatibility complex (MHC) molecules, co-stimulatory molecules (B7-1 and B7-2), and indoleamine dioxygenase (IDO), was examined by reverse transcriptase polymerase chain reaction, flow cytometry, and immunofluorescence staining with and without IFN-gamma stimulation. Results: RPEs expressed IDO and class II MHC molecules under IFN-gamma stimulation. However, B7-1 and B7-2 were not expressed. RPE significantly suppressed MLR in the absence of IFN-gamma prestimulation. This phenomenon was enhanced by IFN-gamma stimulation. The addition of 1-methyl tryptophan l into the culture medium successfully reversed RPE immunosuppression. Conclusions: The expression of IDO may in part explain RPE-mediated immune suppression effects.Sugita S, 2008, J IMMUNOL, V181, P7525Usui Y, 2008, EXP EYE RES, V86, P52, DOI 10.1016/j.exer.2007.09.007Gregerson DS, 2007, INVEST OPHTH VIS SCI, V48, P4654, DOI 10.1167/iovs.07-0286Sugita S, 2006, EXP EYE RES, V83, P1459, DOI 10.1016/j.exer.2006.08.005Zamiri P, 2006, INVEST OPHTH VIS SCI, V47, P3912, DOI 10.1167/iovs.05-1267Agaugue S, 2006, J IMMUNOL, V177, P2061Kaestel CG, 2005, CURR EYE RES, V30, P375Zamiri P, 2005, INVEST OPHTH VIS SCI, V46, P908, DOI 10.1167/iovs.04-0362Munn DH, 2004, J IMMUNOL, V172, P4100Sugita S, 2004, J IMMUNOL, V172, P4184Streilein JW, 2003, NAT REV IMMUNOL, V3, P879, DOI 10.1038/nri1224Sun DM, 2003, J NEUROIMMUNOL, V144, P1, DOI 10.1016/S0165-5728(03)00248-0Sugita S, 2003, J EXP MED, V198, P161, DOI 10.1084/jem.20030097Ishida K, 2003, OCUL IMMUNOL INFLAMM, V11, P91Grohmann U, 2003, TRENDS IMMUNOL, V24, P242, DOI 10.1016/S1471-4906(03)00072-3Momma Y, 2003, INVEST OPHTH VIS SCI, V44, P2026, DOI 10.1167/iovs.02-0980Frumento G, 2002, J EXP MED, V196, P459, DOI 10.1084/jem.20020121Streilein JW, 2002, HUM IMMUNOL, V63, P435Streilein JW, 2002, DNA CELL BIOL, V21, P453Kanuga N, 2002, INVEST OPHTH VIS SCI, V43, P546Jorgensen A, 2001, EXP EYE RES, V73, P723, DOI 10.1006/exer.2001.1082Wolfram RM, 2000, INT J CANCER, V88, P239Wenkel H, 2000, INVEST OPHTH VIS SCI, V41, P3467Babcock TA, 2000, CYTOKINE, V12, P588Hollborn M, 2000, CURR EYE RES, V20, P488Farrokh-Siar L, 1999, GRAEF ARCH CLIN EXP, V237, P934Mellor AL, 1999, IMMUNOL TODAY, V20, P469Enzmann V, 1999, OPHTHALMIC RES, V31, P256Munn DH, 1999, J EXP MED, V189, P1363Bodaghi B, 1999, J IMMUNOL, V162, P957Holtkamp GM, 1999, EUR J IMMUNOL, V29, P215Nagineni CN, 1996, INFECT IMMUN, V64, P4188Nagineni CN, 1996, CYTOKINE, V8, P622Devine L, 1996, IMMUNOLOGY, V88, P456Malina HZ, 1996, GRAEF ARCH CLIN EXP, V234, P457PLATTS KE, 1995, INVEST OPHTH VIS SCI, V36, P2262LIVERSIDGE J, 1993, CELL IMMUNOL, V149, P315LIVERSIDGE JM, 1988, CLIN EXP IMMUNOL, V73, P489