1
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Hernandez BJ, Skiba NP, Plössl K, Strain M, Liu Y, Grigsby D, Kelly U, Cady MA, Manocha V, Maminishkis A, Watkins T, Miller SS, Ashley‐Koch A, Stamer WD, Weber BHF, Bowes Rickman C, Klingeborn M. Polarized Desmosome and Hemidesmosome Shedding via Small Extracellular Vesicles is an Early Indicator of Outer Blood-Retina Barrier Dysfunction. J Extracell Biol 2023; 2:e116. [PMID: 38108061 PMCID: PMC10720597 DOI: 10.1002/jex2.116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 08/30/2023] [Accepted: 09/11/2023] [Indexed: 12/19/2023]
Abstract
The retinal pigmented epithelium (RPE) constitutes the outer blood-retinal barrier, enables photoreceptor function of the eye, and is constantly exposed to oxidative stress. As such, dysfunction of the RPE underlies pathology leading to development of age-related macular degeneration (AMD), the leading cause of vision loss among the elderly in industrialized nations. A major responsibility of the RPE is to process photoreceptor outer segments, which relies on the proper functioning of its endocytic pathways and endosomal trafficking. Exosomes and other extracellular vesicles (EVs) from RPE are an essential part of these pathways and may be early indicators of cellular stress. To test the role of small EVs (sEVs) including exosomes, that may underlie the early stages of AMD, we used a polarized primary RPE cell culture model under chronic subtoxic oxidative stress. Unbiased proteomic analyses of highly purified basolateral sEVs from oxidatively stressed RPE cultures revealed changes in proteins involved in epithelial barrier integrity. There were also significant changes in proteins accumulating in the basal-side sub-RPE extracellular matrix during oxidative stress, that could be prevented with an inhibitor of sEV release. Thus, chronic subtoxic oxidative stress in primary RPE cultures induces changes in sEV content, including basal-side specific desmosome and hemidesmosome shedding via sEVs. These findings provide novel biomarkers of early cellular dysfunction and opportunity for therapeutic intervention in age-related retinal diseases (e.g., AMD).
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Affiliation(s)
- Belinda J. Hernandez
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Nikolai P. Skiba
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Karolina Plössl
- Institute of Human GeneticsUniversity of RegensburgRegensburgGermany
| | - Madison Strain
- Duke Molecular Physiology Institute, Department of MedicineDuke UniversityDurhamNorth CarolinaUSA
| | - Yutao Liu
- Department of Cellular Biology and AnatomyAugusta UniversityAugustaGeorgiaUSA
| | - Daniel Grigsby
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Una Kelly
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Martha A. Cady
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Vikram Manocha
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
| | - Arvydas Maminishkis
- Ophthalmic Genetics and Visual Function Branch, Section on Epithelial and Retinal Physiology and DiseaseNational Eye Institute, National Institutes of HealthBethesdaMarylandUSA
| | - TeddiJo Watkins
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Office of Animal Welfare Assurance, Duke Animal Care and Use ProgramDuke UniversityDurhamNorth CarolinaUSA
| | - Sheldon S. Miller
- Ophthalmic Genetics and Visual Function Branch, Section on Epithelial and Retinal Physiology and DiseaseNational Eye Institute, National Institutes of HealthBethesdaMarylandUSA
| | - Allison Ashley‐Koch
- Duke Molecular Physiology Institute, Department of MedicineDuke UniversityDurhamNorth CarolinaUSA
| | - W. Daniel Stamer
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Department of Biomedical EngineeringDuke UniversityDurhamNorth CarolinaUSA
| | - Bernhard H. F. Weber
- Institute of Human GeneticsUniversity of RegensburgRegensburgGermany
- Institute of Clinical Human GeneticsUniversity Hospital RegensburgRegensburgGermany
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- Department of Cell BiologyDuke UniversityDurhamNorth CarolinaUSA
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke Eye CenterDuke UniversityDurhamNorth CarolinaUSA
- McLaughlin Research InstituteGreat FallsMontanaUSA
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Grigsby D, Klingeborn M, Kelly U, Chew LA, Asokan A, Devlin G, Smith S, Keyes L, Timmers A, Scaria A, Bowes Rickman C. AAV Gene Augmentation of Truncated Complement Factor H Differentially Rescues Ocular Complement Dysregulation in a Mouse Model. Invest Ophthalmol Vis Sci 2023; 64:25. [PMID: 37471073 PMCID: PMC10365136 DOI: 10.1167/iovs.64.10.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023] Open
Abstract
Purpose Complement dysregulation in the eye has been implicated in the pathogenesis of age-related macular degeneration (AMD), and genetic variants of complement factor H (CFH) are strongly associated with AMD risk. We therefore aimed to untangle the role of CFH and its splice variant, factor H-like 1 (FHL-1), in ocular complement regulation derived from local versus circulating sources. We assessed the therapeutic efficacy of adeno-associated viruses (AAVs) expressing human FHL-1 and a truncated version of CFH (tCFH), which retains the functional N- and C-terminal ends of the CFH protein, in restoring the alternative complement pathway in Cfh-/- mouse eyes and plasma. Methods Using Cfh-/- mice as a model of complement dysregulation, AAV vectors expressing tCFH or FHL-1 were injected subretinally or via tail vein, and the efficacy of the constructs was evaluated. Results Following subretinal injections, tCFH expression rescued factor B (FB) retention in the eye, but FHL-1 expression did not. By contrast, both constructs restored FB detection in plasma following tail vein injections. Both tCFH and FHL-1 proteins accumulated in the posterior eyecup from the circulation following liver transduction; however, neither was able to significantly regulate local ocular complement. Conclusions Our findings demonstrate that the C-terminus of human CFH is necessary for complement regulation in the murine eye. Furthermore, exogenous CFH must be synthesized locally to maximize complement regulation in the retina. These findings establish a critical foundation for development of CFH augmentation-based gene therapies for the eye.
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Affiliation(s)
- Daniel Grigsby
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
- McLaughlin Research Institute, Great Falls, Montana, United States
| | - Una Kelly
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Lindsey A Chew
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, United States
| | - Aravind Asokan
- Departments of Surgery, Molecular Genetics and Microbiology, and Biomedical Engineering, Duke University School of Medicine, Durham, North Carolina, United States
| | - Garth Devlin
- Departments of Surgery, Molecular Genetics and Microbiology, and Biomedical Engineering, Duke University School of Medicine, Durham, North Carolina, United States
| | - Sharon Smith
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
| | - Lisa Keyes
- Pfizer, Morrisville, North Carolina, United States
| | - Adrian Timmers
- Editas Medicine, Cambridge, Massachusetts, United States
| | - Abraham Scaria
- Applied Genetic Technologies Corporation, Alachua, Florida, United States
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina, United States
- Department of Cell Biology, Duke University School of Medicine, Durham, North Carolina, United States
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3
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Hernandez BJ, Skiba NP, Plößl K, Strain M, Grigsby D, Kelly U, Cady MA, Manocha V, Maminishkis A, Watkins T, Miller SS, Ashley-Koch A, Stamer WD, Weber BHF, Rickman CB, Klingeborn M. Polarized Desmosome and Hemidesmosome Shedding via Exosomes is an Early Indicator of Outer Blood-Retina Barrier Dysfunction. bioRxiv 2023:2023.06.12.544677. [PMID: 37398366 PMCID: PMC10312606 DOI: 10.1101/2023.06.12.544677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
The retinal pigmented epithelium (RPE) constitutes the outer blood-retinal barrier, enables photoreceptor function of the eye, and is constantly exposed to oxidative stress. As such, dysfunction of the RPE underlies pathology leading to development of age-related macular degeneration (AMD), the leading cause of vision loss among the elderly in industrialized nations. A major responsibility of the RPE is to process photoreceptor outer segments, which relies on the proper functioning of its endocytic pathways and endosomal trafficking. Exosomes and other extracellular vesicles from RPE are an essential part of these pathways and may be early indicators of cellular stress. To test the role of exosomes that may underlie the early stages of AMD, we used a polarized primary RPE cell culture model under chronic subtoxic oxidative stress. Unbiased proteomic analyses of highly purified basolateral exosomes from oxidatively stressed RPE cultures revealed changes in proteins involved in epithelial barrier integrity. There were also significant changes in proteins accumulating in the basal-side sub-RPE extracellular matrix during oxidative stress, that could be prevented with an inhibitor of exosome release. Thus, chronic subtoxic oxidative stress in primary RPE cultures induces changes in exosome content, including basal-side specific desmosome and hemidesmosome shedding via exosomes. These findings provide novel biomarkers of early cellular dysfunction and opportunity for therapeutic intervention in age-related retinal diseases, (e.g., AMD) and broadly from blood-CNS barriers in other neurodegenerative diseases.
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Toomey CB, Landowski M, Klingeborn M, Kelly U, Deans J, Dong H, Harrabi O, Van Blarcom T, Yeung YA, Grishanin R, Lin JC, Saban DR, Bowes Rickman C. Effect of Anti-C5a Therapy in a Murine Model of Early/Intermediate Dry Age-Related Macular Degeneration. Invest Ophthalmol Vis Sci 2018; 59:662-673. [PMID: 29392311 PMCID: PMC5795897 DOI: 10.1167/iovs.17-23134] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose A large body of evidence supports a central role for complement activation in the pathobiology of age-related macular degeneration (AMD), including plasma complement component 5a (C5a). Interestingly, C5a is a chemotactic agent for monocytes, a cell type also shown to contribute to AMD. However, the role monocytes play in the pathogenesis of “dry” AMD and the pharmacologic potential of targeting C5a to regulate these cells are unclear. We addressed these questions via C5a blockade in a unique model of early/intermediate dry AMD and large panel flow cytometry to immunophenotype monocytic involvement. Methods Heterozygous complement factor H (Cfh+/−) mice aged to 90 weeks were fed a high-fat, cholesterol-enriched diet (Cfh+/−∼HFC) for 8 weeks and were given weekly intraperitoneal injections of 30 mg/kg anti-C5a (4C9, Pfizer). Flow cytometry, retinal pigmented epithelium (RPE) flat mounts, and electroretinograms were used to characterize anti-C5a treatment. Results Aged Cfh+/− mice developed RPE damage, sub-RPE basal laminar deposits, and attenuation of visual function and immune cell recruitment to the choroid that was accompanied by expression of inflammatory and extracellular matrix remodeling genes following 8 weeks of HFC diet. Concomitant systemic administration of an anti-C5a antibody successfully inhibited local recruitment of mononuclear phagocytes to the choroid–RPE interface but did not ameliorate these AMD-like pathologies in this mouse model. Conclusions These results show that immunotherapy targeting C5a is not sufficient to block the development of the AMD-like pathologies observed in Cfh+/−∼HFC mice and suggest that other complement components or molecules/mechanisms may be driving “early” and “intermediate” AMD pathologies.
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Affiliation(s)
- Christopher B Toomey
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States.,Shiley Eye Institute, Department of Ophthalmology, University of California-San Diego, San Diego, California, United States
| | - Michael Landowski
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Una Kelly
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - John Deans
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States
| | - Holly Dong
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Ons Harrabi
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | | | - Yik Andy Yeung
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Ruslan Grishanin
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - John C Lin
- Rinat, Pfizer Inc, South San Francisco, California, United States
| | - Daniel R Saban
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina, United States.,Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, United States
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5
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Klingeborn M, Dismuke WM, Skiba NP, Kelly U, Stamer WD, Bowes Rickman C. Directional Exosome Proteomes Reflect Polarity-Specific Functions in Retinal Pigmented Epithelium Monolayers. Sci Rep 2017; 7:4901. [PMID: 28687758 PMCID: PMC5501811 DOI: 10.1038/s41598-017-05102-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/30/2017] [Indexed: 01/09/2023] Open
Abstract
The retinal pigmented epithelium (RPE) forms the outer blood-retinal barrier in the eye and its polarity is responsible for directional secretion and uptake of proteins, lipoprotein particles and extracellular vesicles (EVs). Such a secretional division dictates directed interactions between the systemic circulation (basolateral) and the retina (apical). Our goal is to define the polarized proteomes and physical characteristics of EVs released from the RPE. Primary cultures of porcine RPE cells were differentiated into polarized RPE monolayers on permeable supports. EVs were isolated from media bathing either apical or basolateral RPE surfaces, and two subpopulations of small EVs including exosomes, and dense EVs, were purified and processed for proteomic profiling. In parallel, EV size distribution and concentration were determined. Using protein correlation profiling mass spectrometry, a total of 631 proteins were identified in exosome preparations, 299 of which were uniquely released apically, and 94 uniquely released basolaterally. Selected proteins were validated by Western blot. The proteomes of these exosome and dense EVs preparations suggest that epithelial polarity impacts directional release. These data serve as a foundation for comparative studies aimed at elucidating the role of exosomes in the molecular pathophysiology of retinal diseases and help identify potential therapeutic targets and biomarkers.
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Affiliation(s)
- Mikael Klingeborn
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA.
| | - W Michael Dismuke
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA
| | - Nikolai P Skiba
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA
| | - Una Kelly
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA
| | - W Daniel Stamer
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA.,Department of Biomedical Engineering, Duke University, Durham, NC, 27710, USA
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke Eye Center, Duke University, Durham, NC, 27710, USA. .,Department of Cell Biology, Duke University, Durham, NC, 27710, USA.
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6
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Ding JD, Kelly U, Landowski M, Toomey CB, Groelle M, Miller C, Smith SG, Klingeborn M, Singhapricha T, Jiang H, Frank MM, Bowes Rickman C. Expression of human complement factor H prevents age-related macular degeneration-like retina damage and kidney abnormalities in aged Cfh knockout mice. Am J Pathol 2014; 185:29-42. [PMID: 25447048 DOI: 10.1016/j.ajpath.2014.08.026] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 01/17/2023]
Abstract
Complement factor H (CFH) is an important regulatory protein in the alternative pathway of the complement system, and CFH polymorphisms increase the genetic risk of age-related macular degeneration dramatically. These same human CFH variants have also been associated with dense deposit disease. To mechanistically study the function of CFH in the pathogenesis of these diseases, we created transgenic mouse lines using human CFH bacterial artificial chromosomes expressing full-length human CFH variants and crossed these to Cfh knockout (Cfh(-/-)) mice. Human CFH protein inhibited cleavage of mouse complement component 3 and factor B in plasma and in retinal pigment epithelium/choroid/sclera, establishing that human CFH regulates activation of the mouse alternative pathway. One of the mouse lines, which express relatively higher levels of CFH, demonstrated functional and structural protection of the retina owing to the Cfh deletion. Impaired visual function, detected as a deficit in the scotopic electroretinographic response, was improved in this transgenic mouse line compared with Cfh(-/-) mice, and transgenics had a thicker outer nuclear layer and less sub-retinal pigment epithelium deposit accumulation. In addition, expression of human CFH also completely protected the mice from developing kidney abnormalities associated with loss of CFH. These humanized CFH mice present a valuable model for study of the molecular mechanisms of age-related macular degeneration and dense deposit disease and for testing therapeutic targets.
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Affiliation(s)
- Jin-Dong Ding
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Una Kelly
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Michael Landowski
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Christopher B Toomey
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina; Department of Cell Biology, Duke University Medical Center, Durham, North Carolina
| | - Marybeth Groelle
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Chelsey Miller
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Stephanie G Smith
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Mikael Klingeborn
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Terry Singhapricha
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina
| | - Haixiang Jiang
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina
| | - Michael M Frank
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina
| | - Catherine Bowes Rickman
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina; Department of Cell Biology, Duke University Medical Center, Durham, North Carolina.
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Abstract
Variations in several complement genes are now known to be significant risk factors for the development of age-related macular degeneration (AMD). Despite dramatic effects on disease susceptibility, the underlying mechanisms by which common polymorphisms in complement proteins alter disease risk have remained unclear. Genetically modified mice in which the activity of the complement has been altered are available and can be used to investigate the role of complement in the pathogenesis of AMD. In this mini review, we will discuss some existing complement models of AMD and our efforts to develop and characterize the ocular phenotype in a variety of mice in which complement is either chronically activated or inhibited. A spectrum of complement dysregulation was modeled on the APOE4 AMD mouse model by crossing these mice to complement factor H knockout (cfh-/-) mice to test the impact of excess complement activation, and by crossing them to soluble-complement-receptor-1-related protein y (sCrry) mice, in which sCrry acts as a potent inhibitor of mouse complement acting in a manner similar to CFH. In addition, we have also generated humanized CFH mice expressing normal and risk variants of CFH.
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Affiliation(s)
- Jin-Dong Ding
- Department of Ophthalmology, Duke University Medical Center, 2351 Erwin Rd, 27710, Durham, NC, USA,
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8
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Kelly U, Ding JD, Landowski M, Groelle M, Jiang H, Skiba N, Frank M, Rickman CB. Development of humanized complement factor H transgenic mice to interrogate the effect of age-related macular degeneration risk associated variants in vivo. Immunobiology 2012. [DOI: 10.1016/j.imbio.2012.08.101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Kelly U, Yu L, Kumar P, Ding JD, Jiang H, Hageman GS, Arshavsky VY, Frank MM, Hauser MA, Rickman CB. Heparan sulfate, including that in Bruch's membrane, inhibits the complement alternative pathway: implications for age-related macular degeneration. J Immunol 2010; 185:5486-94. [PMID: 20876352 DOI: 10.4049/jimmunol.0903596] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An imbalance between activation and inhibition of the complement system has been implicated in the etiologies of numerous common diseases. Allotypic variants of a key complement fluid-phase regulatory protein, complement factor H (CFH), are strongly associated with age-related macular degeneration (AMD), a leading cause of worldwide visual dysfunction, although its specific role in AMD pathogenesis is still not clear. CFH was isolated from individuals carrying combinations of two of the nonsynonymous coding variants most strongly associated with AMD risk, V62/H402 (risk haplotype variants), I62/Y402 (nonrisk haplotype variants), and V62/Y402. These proteins were used in two functional assays (cell surface- and fluid-phase-based) measuring cofactor activity of CFH in the factor I-mediated cleavage of C3b. Although no variant-specific differences in the cofactor activity were detected, when heparan sulfate (HS) was added to these assays, it accelerated the rate of C3b cleavage, and this effect could be modulated by degree of HS sulfation. Bruch's membrane/choroid, a site of tissue damage in AMD, contains high concentrations of glycosaminoglycans, including HS. Addition of human Bruch's membrane/choroid to the fluid-phase assay accelerated the C3b cleavage, and this effect was lost posttreatment of the tissue with heparinase III. Binding of CFH variants to Bruch's membrane/choroid isolated from elderly, non-AMD donor eyes, was similar, as was the functional activity of bound CFH. These findings refine our understanding of interactions of HS and complement and support the hypothesis that these interactions play a role in the transition between normal aging and AMD in Bruch's membrane/choroid.
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Affiliation(s)
- Una Kelly
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
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10
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Ellebaek Pedersen M, Qvist N, Bisgaard C, Kelly U, Bernhard A, Møller Pedersen S. Peritoneal microdialysis. Early diagnosis of anastomotic leakage after low anterior resection for rectosigmoid cancer. Scand J Surg 2010; 98:148-54. [PMID: 19919919 DOI: 10.1177/145749690909800304] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The aim of the present study was to evaluate the efficacy and safety of intraperitoneal microdialysis in early detection of anastomotic leakage after low anterior resection for rectosigmoid cancer. METHODS In a series of 116 consecutive patients scheduled for low anterior resection for rectosigmoid cancer, a total of 50 patients consented to participate. Peritoneal microdialysis was performed by a 1 mm thin catheter anchored in close proximity to the anastomosis. Five patients were excluded due to catheter malfunction. Average microdialysis time in the remaining 45 patients was 177.6 (80-252) hours. Samples were collected every 4-hours, and the concentration of glucose, lactate, pyruvate and glycerol was measured. RESULTS Four patients developed symptomatic anastomotic leakage. Two patients developed non-abdominal sepsis. In 38 patients the postoperative course was uncomplicated, considering major complications, and they served as controls. In three patients with late (>or=10 days) anastomotic leakage a significant increase in concentration of lactate and lactate/pyruvate ratio (L/P-ratio) was seen several days prior to development of clinical symptoms. In one patient with early anastomotic leakage it coincided with the development of clinical symptoms. In the two patients with non-abdominal sepsis the values were within normal range. CONCLUSION Peritoneal microdialysis is a safe and promising tool in early diagnosis of anastomotic leakage after low anterior resection for rectosigmoid cancer.
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11
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Kelly U, Rickman CB, Postel EA, Hauser MA, Hageman GS, Arshavsky VY, Skiba NP. Rapid and sensitive method for detection of Y402, H402, I62, and V62 variants of complement factor H in human plasma samples using mass spectrometry. Invest Ophthalmol Vis Sci 2008; 50:1540-5. [PMID: 19029036 DOI: 10.1167/iovs.08-2782] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Variations in the complement factor H (CFH) gene are tightly associated with age-related macular degeneration (AMD) across diverse populations. Of the many nonsynonymous coding variants in CFH, two are most strongly associated with increased risk of AMD: isoleucine 62 to valine (I62V) and tyrosine 402 to histidine (Y402H). Detection of these variations in a patient's blood is important for a risk assessment of AMD and disease prognosis. However, traditional methods of genetic analysis cannot be used for measuring CFH allotypes in some sources of human plasma and other biological fluids not containing DNA. The purpose was to develop a protein-based method of detecting CFH allotypes. METHODS A combination of a single-step affinity enrichment of CFH, gel separation, and mass spectrometry identification of the CFH peptides spanning amino acids at positions 62 and 402 was used to identify individual CFH allotypes. RESULTS The CFH isoforms V62, I62, H402, and Y402 were reliably detected based on identification of tryptic peptides with masses of 1148.59 Da, 1162.60 Da, 2031.88 Da, and 2057.88 Da, respectively, using MALDI-TOF-TOF. The presence or absence pattern of these peptides in mass spectra of different CFH samples robustly correlated with all nine genotypes of CFH, as a result of variations at positions 62 and 402. CONCLUSIONS A rapid and sensitive method has been developed for detection of V62, I62, H402, and Y402 variants of CFH in human plasma samples using mass spectrometry. This method can be used in clinical laboratories equipped with a basic inexpensive mass spectrometer capable of performing peptide fingerprinting.
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Affiliation(s)
- Una Kelly
- Department of Ophthalmology, Duke University Medical Center, Durham, North Carolina 27710, USA
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12
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Yu L, Kelly U, Ebright JN, Malek G, Saloupis P, Rickman D, McKay BS, Arshavsky VY, Rickman CB. Oxidative stress-induced expression and modulation of Phosphatase of Regenerating Liver-1 (PRL-1) in mammalian retina. Biochim Biophys Acta 2007; 1773:1473-82. [PMID: 17673310 PMCID: PMC2118714 DOI: 10.1016/j.bbamcr.2007.06.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 06/06/2007] [Accepted: 06/18/2007] [Indexed: 11/18/2022]
Abstract
The phosphatase of regenerating liver-1, PRL-1, gene was detected in a screen for foveal cone photoreceptor-associated genes. It encodes a small protein tyrosine phosphatase that was previously immunolocalized to the photoreceptors in primate retina. Here we report that in cones and cone-derived cultured cells both PRL-1 activity and PRL-1 gene expression are modulated under oxidative stress. Oxidation reversibly inhibited the phosphatase activity of PRL-1 due to the formation of an intramolecular disulfide bridge between Cys104 within the active site and another conserved Cys, Cys49. This modulation was observed in vitro, in cell culture and in isolated retinas exposed to hydrogen peroxide. The same treatment caused a rapid increase in PRL-1 expression levels in cultured cells which could be blocked by the protein translation inhibitor, cycloheximide. Increased PRL-1 expression was also observed in living rats subjected to constant light exposure inducing photooxidative stress. We further demonstrated that both oxidation and overexpression of PRL-1 upon oxidative stress are greatly enhanced by inhibition of the glutathione system responsible for cellular redox regulation. These findings suggest that PRL-1 is a molecular component of the photoreceptor's response to oxidative stress acting upstream of the glutathione system.
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Affiliation(s)
- Ling Yu
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Una Kelly
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Jessica N. Ebright
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Goldis Malek
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Peter Saloupis
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Dennis Rickman
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Brian S. McKay
- Departments of Ophthalmology and Cell Biology and Anatomy, University of Arizona, Tucson, AZ 85711, USA
| | - Vadim Y. Arshavsky
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Catherine Bowes Rickman
- Departments of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
- Corresponding Author. Department of Ophthalmology, Duke University Medical Center, Albert Eye Research Institute Room 5010, Box 3802, Erwin Road, Durham, NC 27710, USA. Tel.: +1 (919) 668-0648; Fax: +1 (919) 684 3687. E-Mail: (Catherine Bowes Rickman, Ph.D.)
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Thompson CL, Bowes Rickman C, Shaw SJ, Ebright JN, Kelly U, Sancar A, Rickman DW. Expression of the Blue-Light Receptor Cryptochrome in the Human Retina. ACTA ACUST UNITED AC 2003; 44:4515-21. [PMID: 14507900 DOI: 10.1167/iovs.03-0303] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE To analyze the patterns of expression of the cryptochromes, CRY1 and CRY2, in the human retina and to correlate expression of these putative blue-light receptors with nonvisual photoreceptor localization. METHODS CRY1 and CRY2 mRNA expression was analyzed in 4-mm diameter punches of macula and midperipheral human retina by quantitative RT-PCR. CRY2 protein expression was examined by immunohistochemistry in cross sections of human retina, and its subcellular localization was determined by immunoblot analysis of fractionated human retinal extracts. RESULTS CRY2 mRNA was 11 times more abundant than CRY1 throughout adult human retina. CRY2 immunoreactivity was detected in most cells in the ganglion cell layer (GCL) and in a subset of cells in the inner nuclear layer (INL) in both the macula and periphery. Immunoperoxidase staining further revealed that CRY2 was localized throughout the cytoplasm of cells in the GCL as well as within nuclei. This intracellular localization of CRY2 was confirmed by immunoblot analysis of fractionated human retinal extracts. CONCLUSIONS Photopigments governing circadian photoreception have been localized to the inner retina. The relative abundance of CRY2 transcripts, coupled with CRY2 localization to the inner retina, supports a photoreceptive role for CRY2 in human retina. Furthermore, the discovery that CRY2 is also localized within the cytoplasm of some cells in the GCL, suggests it may perform a function separate from its known nuclear role in the transcriptional feedback loop underlying the molecular circadian clock.
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Affiliation(s)
- Carol L Thompson
- Department of Biochemistry and Biophysics, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA
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D'Avolio D, Hawkins JW, Haggerty LA, Kelly U, Barrett R, Durno Toscano SE, Dwyer J, Higgins LP, Kearney M, Pearce CW, Aber CS, Mahony D, Bell M. Screening for abuse: barriers and opportunities. Health Care Women Int 2001; 22:349-62. [PMID: 11813784 DOI: 10.1080/07399330152398891] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Domestic abuse is the leading cause of injuries and death among women of childbearing age in the United States. The broad purpose of this research is to discover how pregnant women's psychological and behavioral responses to abuse affect birth outcomes. To select a diverse sample of women, we identified 8 prenatal care sites and completed the human subjects approval process with each. Rates of screening for abuse range from all but 12 women over a 2-1/2-year period at one site to no screening for abuse at another site. In this article, we will review pertinent literature and discuss the supports and barriers we observed when implementing an abuse screening program using the Abuse Assessment Screen, a well-tested and valid clinical instrument. Suggestions will be made for improving the screening rates at those sites where screening is absent or inconsistent.
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Affiliation(s)
- D D'Avolio
- Boston College School of Nursing, Chestnut Hill, Massachusetts, USA
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Haggerty LA, Kelly U, Hawkins J, Pearce C, Kearney MH. Pregnant women's perceptions of abuse. J Obstet Gynecol Neonatal Nurs 2001; 30:283-90. [PMID: 11383951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
OBJECTIVE To determine whether pregnant women's perceptions of abuse severity and danger, and their ability to control the abuse, are significantly correlated with the acts of abuse they experience, and to find out whether relationships exist among women's appraisals of abuse severity, danger, and their perceived ability to stop the abuse. DESIGN A correlational design was used to compare the abusive acts experienced by the women and their perceptions of that abuse. SETTING Nine prenatal clinics in urban areas of the northeastern United States. PARTICIPANTS Sixty-one ethnically diverse, pregnant abused women were interviewed. MAIN OUTCOME MEASURE Pearson's product-moment correlations were used to examine relationships between abusive experiences and women's perceptions of abuse. RESULTS Women's perceptions of abuse severity were modestly correlated with threatened (r = .25) and actual violence (r = .36). Perceptions of abuse severity and danger were correlated (r = .41). CONCLUSIONS Women's beliefs about abuse severity, danger, and their ability to control abuse cannot be fully comprehended by exploring the discrete acts they experience. Further research is needed to identify additional factors that influence those beliefs.
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Affiliation(s)
- L A Haggerty
- Boston College, School of Nursing, Chestnut Hill, MA, USA.
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Reeves WG, Kelly U. Insulin antibodies induced by bovine insulin therapy. Clin Exp Immunol 1982; 50:163-70. [PMID: 6756728 PMCID: PMC1536847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Insulin antibodies are detectable in the sera of most patients within 3-4 months of starting treatment with conventional bovine insulins. Various factors determine the immunogenicity of insulin preparations including the genetic background of the recipient. This causes wide variation in response. Solid phase absorption studies as well as competitive binding in fluid phase indicate that the antibodies formed are almost always specific for determinants shared by the endogenous human molecule. This has important implications for the metabolic effect of insulin antibodies in vivo as well as for mechanisms of autoantibody production in man.
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Abstract
A 125I-labelled insulin binding assay is described in which IgG antibody is precipitated by the addition of an optimal concentration of second antibody. Other features include the removal of unlabelled insulin from test sera prior to assay and the use of 22Na as a volume marker. This approach overcomes problems associated with previous assays for insulin antibodies. Clear differences are seen in the IgG insulin binding capacity (IBC) of sera from patients with insulin resistance and injection site lipo-atrophy when compared with insulin-treated diabetics who lack such complications. The precision and flexibility of this technique make it particularly suitable for studies of the immune response to different species and forms of insulin.
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Schubert J, Kirsch E, Kelly U, Gorski J, Nitzsche H, Heidl G, Schorcht J. [Lymphogenic metastasis in prostate carcinoma and radiation therapy]. Z Urol Nephrol 1979; 72:175-83. [PMID: 463373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Our examinations allow the following conclusions: 1. Before the beginning of a curative radiotherapy of the carcinoma of the prostate gland in a negative and questionably positive lymphogramme the pelvic lymphadenectomy with histologic examination of the lymph nodes is indicated. 2. In the negative findings of the histologically examined lymph nodes an exclusive local tumour irradiation is justified. 3. If in regional and negative findings micrometastases appear in the area of juxtaregional lymph nodes the additional curative irradiation of the pelvic lymph nodes seems to be indicated for the comprehension of the regional lymph nodes. 4. When there are micrometastases in the area of the aa. iliacae communes or macroscopically extended metastases in the regional and juxtaregional lymph area, so we regard as a rule a radiotherapy of the carcinoma of the prostate gland no more indicated and recommend a contrasexual treatment. The necessary expansion of the radiotherapy is according to our hitherto existing experiences badly tolerated by the for the most part older patients. 5. The intraoperative labelling of the prostate gland and the determination of the size of the prostate gland facilitate the localisation of the tumour for the radiotherapist.
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