@article {1091, title = {Optical Coherence Tomography Angiography of RPGR-Associated Retinitis Pigmentosa Suggests Foveal Avascular Zone is a Biomarker for Vision Loss.}, journal = {Ophthalmic Surg Lasers Imaging Retina}, volume = {50}, year = {2019}, month = {2019 02 01}, pages = {e44-e48}, abstract = {

RPGR-associated retinitis pigmentosa (RP) is a progressive disease with retina degeneration. Optical coherence tomography angiography (OCTA) is an imaging technique that provides novel insights. The authors report two affected male siblings who underwent OCTA imaging. The area of the foveal avascular zone (FAZ) was measured. Although the younger sibling exhibited more advanced clinical disease, his visual acuity was superior to his older sibling. OCTA imaging revealed a better preserved FAZ in the younger sibling as the reason for this. It also highlighted attenuation of choriocapillaris / choroid layers as biomarkers for disease severity. This provides new insights into retinal degeneration in RPGR-associated RP. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e44-e48.].

}, keywords = {Biomarkers, Capillaries, Choroid, Eye Proteins, Fluorescein Angiography, Fovea Centralis, Humans, Male, Middle Aged, Retinitis Pigmentosa, Tomography, Optical Coherence, Vision Disorders}, issn = {2325-8179}, doi = {10.3928/23258160-20190129-18}, author = {Tang, Peter H and Jauregui, Ruben and Tsang, Stephen H and Bassuk, Alexander G and Mahajan, Vinit B} } @article {2047, title = {Therapeutic Window for Phosphodiesterase 6-Related Retinitis Pigmentosa.}, journal = {JAMA Ophthalmol}, volume = {137}, year = {2019}, month = {2019 Jun 01}, pages = {679-680}, keywords = {Cone-Rod Dystrophies, Cyclic Nucleotide Phosphodiesterases, Type 6, Eye Proteins, Follow-Up Studies, Humans, Mutation, Retinitis Pigmentosa}, issn = {2168-6173}, doi = {10.1001/jamaophthalmol.2018.6381}, author = {Wang, Nan-Kai and Mahajan, Vinit B and Tsang, Stephen H} } @article {659, title = {BESTROPHIN1 mutations cause defective chloride conductance in patient stem cell-derived RPE.}, journal = {Hum Mol Genet}, volume = {25}, year = {2016}, month = {2016 07 01}, pages = {2672-2680}, abstract = {

Bestrophin1 (BEST1) is expressed in human retinal pigment epithelium (RPE) and mutations in the BEST1 gene commonly cause retinal dysfunction and macular degeneration. BEST1 is presumed to assemble into a calcium-activated chloride channel and be involved in chloride transport but there is no direct evidence in live human RPE cells to support this idea. To test whether BEST1 functions as a chloride channel in living tissue, BEST1-mutant RPE (R218H, L234P, A243T) were generated from patient-derived induced pluripotent stem cells and compared with wild-type RPE in a retinal environment, using a biosensor that visualizes calcium-induced chloride ion flux in the cell. Calcium stimulation elicited chloride ion export in normal RPE but not in RPE derived from three patients with BEST1 mutations. These data, along with three-dimensional modeling, provide evidence that BEST1 assembles into a key calcium-sensing chloride channel in human RPE.

}, keywords = {Bestrophins, Calcium Signaling, Chloride Channels, Chlorides, Eye Proteins, Humans, Induced Pluripotent Stem Cells, Mutation, Retinal Pigment Epithelium, Vitelliform Macular Dystrophy}, issn = {1460-2083}, doi = {10.1093/hmg/ddw126}, author = {Moshfegh, Yasmin and Velez, Gabriel and Li, Yao and Bassuk, Alexander G and Mahajan, Vinit B and Tsang, Stephen H} } @article {637, title = {Reprogramming metabolism by targeting sirtuin 6 attenuates retinal degeneration.}, journal = {J Clin Invest}, volume = {126}, year = {2016}, month = {2016 Dec 01}, pages = {4659-4673}, abstract = {

Retinitis pigmentosa (RP) encompasses a diverse group of Mendelian disorders leading to progressive degeneration of rods and then cones. For reasons that remain unclear, diseased RP photoreceptors begin to deteriorate, eventually leading to cell death and, consequently, loss of vision. Here, we have hypothesized that RP associated with mutations in phosphodiesterase-6 (PDE6) provokes a metabolic aberration in rod cells that promotes the pathological consequences of elevated cGMP and Ca2+, which are induced by the Pde6 mutation. Inhibition of sirtuin 6 (SIRT6), a histone deacetylase repressor of glycolytic flux, reprogrammed rods into perpetual glycolysis, thereby driving the accumulation of biosynthetic intermediates, improving outer segment (OS) length, enhancing photoreceptor survival, and preserving vision. In mouse retinae lacking Sirt6, effectors of glycolytic flux were dramatically increased, leading to upregulation of key intermediates in glycolysis, TCA cycle, and glutaminolysis. Both transgenic and AAV2/8 gene therapy-mediated ablation of Sirt6 in rods provided electrophysiological and anatomic rescue of both rod and cone photoreceptors in a preclinical model of RP. Due to the extensive network of downstream effectors of Sirt6, this study motivates further research into the role that these pathways play in retinal degeneration. Because reprogramming metabolism by enhancing glycolysis is not gene specific, this strategy may be applicable to a wide range of neurodegenerative disorders.

}, keywords = {Animals, Cellular Reprogramming, Cellular Reprogramming Techniques, Citric Acid Cycle, Cyclic GMP, Cyclic Nucleotide Phosphodiesterases, Type 6, Dependovirus, Disease Models, Animal, Eye Proteins, Genetic Therapy, Glycolysis, Mice, Mice, Mutant Strains, Mutation, Retinal Rod Photoreceptor Cells, Retinitis Pigmentosa, Sirtuins, Transduction, Genetic}, issn = {1558-8238}, doi = {10.1172/JCI86905}, author = {Zhang, Lijuan and Du, Jianhai and Justus, Sally and Hsu, Chun-Wei and Bonet-Ponce, Luis and Wu, Wen-Hsuan and Tsai, Yi-Ting and Wu, Wei-Pu and Jia, Yading and Duong, Jimmy K and Mahajan, Vinit B and Lin, Chyuan-Sheng and Wang, Shuang and Hurley, James B and Tsang, Stephen H} } @article {693, title = {Proteomic insight into the molecular function of the vitreous.}, journal = {PLoS One}, volume = {10}, year = {2015}, month = {2015}, pages = {e0127567}, abstract = {

The human vitreous contains primarily water, but also contains proteins which have yet to be fully characterized. To gain insight into the four vitreous substructures and their potential functions, we isolated and analyzed the vitreous protein profiles of three non-diseased human eyes. The four analyzed substructures were the anterior hyaloid, the vitreous cortex, the vitreous core, and the vitreous base. Proteins were separated by multidimensional liquid chromatography and identified by tandem mass spectrometry. Bioinformatics tools then extracted the expression profiles, signaling pathways, and interactomes unique to each tissue. From each substructure, a mean of 2,062 unique proteins were identified, with many being differentially expressed in a specific substructure: 278 proteins were unique to the anterior hyaloid, 322 to the vitreous cortex, 128 to the vitreous base, and 136 to the vitreous core. When the identified proteins were organized according to relevant functional pathways and networks, key patterns appeared. The blood coagulation pathway and extracellular matrix turnover networks were highly represented. Oxidative stress regulation and energy metabolism proteins were distributed throughout the vitreous. Immune functions were represented by high levels of immunoglobulin, the complement pathway, damage-associated molecular patterns (DAMPs), and evolutionarily conserved antimicrobial proteins. The majority of vitreous proteins detected were intracellular proteins, some of which originate from the retina, including rhodopsin (RHO), phosphodiesterase 6 (PDE6), and glial fibrillary acidic protein (GFAP). This comprehensive analysis uncovers a picture of the vitreous as a biologically active tissue, where proteins localize to distinct substructures to protect the intraocular tissues from infection, oxidative stress, and energy disequilibrium. It also reveals the retina as a potential source of inflammatory mediators. The vitreous proteome catalogues the dynamic interactions between the vitreous and surrounding tissues. It therefore could be an indirect and effective method for surveying vitreoretinal disease for specific biomarkers.

}, keywords = {Aged, Aged, 80 and over, Eye Proteins, Female, Gene Expression Regulation, Humans, Male, Middle Aged, Proteome, Proteomics, Vitreous Body}, issn = {1932-6203}, doi = {10.1371/journal.pone.0127567}, author = {Skeie, Jessica M and Roybal, C Nathaniel and Mahajan, Vinit B} } @article {719, title = {Proteomic landscape of the human choroid-retinal pigment epithelial complex.}, journal = {JAMA Ophthalmol}, volume = {132}, year = {2014}, month = {2014 Nov}, pages = {1271-81}, abstract = {

IMPORTANCE: Differences in geographical protein expression in the human choroid-retinal pigment epithelial (RPE) complex may explain molecular predisposition of regions to ophthalmic diseases such as age-related macular degeneration.

OBJECTIVE: To characterize the proteome of the human choroid-RPE complex and to identify differentially expressed proteins in specific anatomic regions.

DESIGN, SETTING, AND PARTICIPANTS: Experimental study of choroid-RPE tissue from 3 nondiseased eyes. The choroid-RPE complex underwent biopsy from beneath the foveal, macular, and peripheral retina. Protein fractions were isolated and subjected to multidimensional liquid chromatography and tandem mass spectrometry. A bioinformatic pipeline matched peptide spectra to the human proteome, assigned gene ontology classification, and identified protein signaling pathways unique to each of the choroid-RPE regions.

MAIN OUTCOMES AND MEASURES: Mean number of mass spectra, statistically significant differentially expressed proteins, gene ontology classification, and pathway representation.

RESULTS: We identified a mean of 4403 unique proteins in each of the foveal, macular, and peripheral choroid-RPE tissues. Six hundred seventy-one differentially expressed proteins included previously known risk factors for retinal diseases related to oxidative stress, inflammation, and the complement cascade. Gene ontology analysis showed that unique categories in the foveal and macular regions included immune process proteins as well as protein complexes and plasma membrane proteins. The peripheral region contained unique antioxidant activity proteins. Many proteins had the highest expression in the foveal or macular regions, including inflammation-related proteins HLA-A, HLA-B, and HLA-C antigens; intercellular adhesion molecule 1 (ICAM-1); S100; transcription factor ERG; antioxidant superoxide dismutase 1 (SOD1); chloride intracellular channel 6 ion (CLIC6); activators of the complement cascade C1q, C6, and C8; and complement factor H. Proteins with higher expression in the periphery included bestrophin 1 (BEST1), transcription factor RNA binding motif protein 39 (RBM39), inflammatory mediator macrophage migration inhibitory factor, antioxidant SOD3, ion channel voltage-dependent anion-selective channel protein 3 (VDAC3), and complement inhibitor CD55. The complement activation was among the highest represented pathways (P < 7.5e-13).

CONCLUSIONS AND RELEVANCE: This proteomic data set identifies novel molecular signatures in anatomically sensitive regions of the choroid-RPE complex. The findings give mechanistic insight into choroid-RPE function, reveal important choroid-RPE processes, and prioritize new pathways for therapeutic targeting.

}, keywords = {Aged, 80 and over, Choroid, Chromatography, Liquid, Computational Biology, Eye Proteins, Female, Gene Expression Regulation, Gene Ontology, Humans, Male, Proteome, Proteomics, Retinal Pigment Epithelium, Tandem Mass Spectrometry}, issn = {2168-6173}, doi = {10.1001/jamaophthalmol.2014.2065}, author = {Skeie, Jessica M and Mahajan, Vinit B} } @article {129, title = {Proteomic analysis of vitreous biopsy techniques.}, journal = {Retina}, volume = {32}, year = {2012}, month = {2012 Nov-Dec}, pages = {2141-9}, abstract = {

PURPOSE: To compare vitreous biopsy methods using analysis platforms used in proteomics biomarker discovery.

METHODS: Vitreous biopsies from 10 eyes were collected sequentially using a 23-gauge needle and a 23-gauge vitreous cutter instrument. Paired specimens were evaluated by UV absorbance spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and liquid chromatography tandem mass spectrometry (LC-MS/MS).

RESULTS: The total protein concentration obtained with a needle and vitrectomy instrument biopsy averaged 1.10 mg/mL (standard error of the mean = 0.35) and 1.13 mg/mL (standard error of the mean = 0.25), respectively. In eight eyes with low or medium viscidity, there was a very high correlation (R = 0.934) between the biopsy methods. When data from 2 eyes with high viscidity vitreous were included, the correlation was reduced (R = 0.704). The molecular weight protein sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of paired needle and vitreous cutter samples were similar, except for a minority of pairs with single band intensity variance. Using LC-MS/MS, equivalent peptides were identified with similar frequencies (R \≥ 0.90) in paired samples.

CONCLUSION: Proteins and peptides collected from vitreous needle biopsies are nearly equivalent to those obtained from a vitreous cutter instrument. This study suggests both techniques may be used for most proteomic and biomarker discovery studies of vitreoretinal diseases, although a minority of proteins and peptides may differ in concentration.

}, keywords = {Adolescent, Aged, Biological Markers, Biopsy, Chromatography, Liquid, Electrophoresis, Polyacrylamide Gel, Eye Diseases, Eye Proteins, Female, Humans, Male, Middle Aged, Proteomics, Spectrophotometry, Ultraviolet, Tandem Mass Spectrometry, Vitrectomy, Vitreous Body, Young Adult}, author = {Skeie, Jessica M and Brown, Eric N and Martinez, Harryl D and Russell, Stephen R and Birkholz, Emily S and Folk, James C and Boldt, H Culver and Gehrs, Karen M and Stone, Edwin M and Wright, Michael E and Mahajan, Vinit B} } @article {141, title = {Evisceration of mouse vitreous and retina for proteomic analyses.}, journal = {Journal of visualized experiments : JoVE}, year = {2011}, month = {2011}, abstract = {

While the mouse retina has emerged as an important genetic model for inherited retinal disease, the mouse vitreous remains to be explored. The vitreous is a highly aqueous extracellular matrix overlying the retina where intraocular as well as extraocular proteins accumulate during disease.(1-3) Abnormal interactions between vitreous and retina underlie several diseases such as retinal detachment, proliferative diabetic retinopathy, uveitis, and proliferative vitreoretinopathy.(1,4) The relative mouse vitreous volume is significantly smaller than the human vitreous (Figure 1), since the mouse lens occupies nearly 75\% of its eye.(5) This has made biochemical studies of mouse vitreous challenging. In this video article, we present a technique to dissect and isolate the mouse vitreous from the retina, which will allow use of transgenic mouse models to more clearly define the role of this extracellular matrix in the development of vitreoretinal diseases.

}, keywords = {Animals, Eye Evisceration, Eye Proteins, Mice, Models, Animal, Proteomics, Retina, Vitreous Body}, author = {Skeie, Jessica M and Tsang, Stephen H and Mahajan, Vinit B} } @article {151, title = {Seroreactivity against aqueous-soluble and detergent-soluble retinal proteins in posterior uveitis.}, journal = {Archives of ophthalmology}, volume = {129}, year = {2011}, month = {2011 Apr}, pages = {415-20}, abstract = {

To characterize the seroreactivity against retinal proteins in patients with posterior uveitis, retinal disease of noninflammatory origin, and healthy controls.

}, keywords = {Adolescent, Adult, Autoantibodies, Autoantigens, Blotting, Western, Electrophoresis, Polyacrylamide Gel, Eye Proteins, Female, Humans, Immunoglobulin A, Immunoglobulin G, Immunoglobulin M, Male, Middle Aged, Retina, Retinal Degeneration, Solubility, Uveitis, Posterior, Young Adult}, author = {Ko, Audrey C and Brinton, Jason P and Mahajan, Vinit B and Zimmerman, Bridget and Brinton, Gregory S and Stone, Edwin M and Folk, James C and Mullins, Robert F} } @article {181, title = {Microarray analysis of corneal fibroblast gene expression after interleukin-1 treatment.}, journal = {Investigative ophthalmology \& visual science}, volume = {43}, year = {2002}, month = {2002 Jul}, pages = {2143-51}, abstract = {

To identify changes in gene expression in human corneal fibroblasts after exposure to interleukin-1alpha.

}, keywords = {Cells, Cultured, Computational Biology, Cornea, Eye Proteins, Fibroblasts, Gene Expression, Gene Expression Profiling, Humans, Interleukin-1, Oligonucleotide Array Sequence Analysis, RNA}, author = {Mahajan, Vinit B and Wei, Cui and McDonnell, Peter J} }