751
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Richards A, Kavanagh D, Atkinson JP. Inherited complement regulatory protein deficiency predisposes to human disease in acute injury and chronic inflammatory statesthe examples of vascular damage in atypical hemolytic uremic syndrome and debris accumulation in age-related macular degeneration. Adv Immunol 2007; 96:141-77. [PMID: 17981206 DOI: 10.1016/s0065-2776(07)96004-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
In this chapter, we examine the role of complement regulatory activity in atypical hemolytic uremic syndrome (aHUS) and age-related macular degeneration (AMD). These diseases are representative of two distinct types of complement-mediated injury, one being acute and self-limited, the other reflecting accumulation of chronic damage. Neither condition was previously thought to have a pathologic relationship to the immune system. However, alterations in complement regulatory protein genes have now been identified as major predisposing factors for the development of both diseases. In aHUS, heterozygous mutations leading to haploinsufficiency and function-altering polymorphisms in complement regulators have been identified, while in AMD, polymorphic haplotypes in complement genes are associated with development of disease. The basic premise is that a loss of function in a plasma or membrane inhibitor of the alternative complement pathway allows for excessive activation of complement on the endothelium of the kidney in aHUS and on retinal debris in AMD. These associations have much to teach us about the host's innate immune response to acute injury and to chronic debris deposition. We all experience cellular injury and, if we live long enough, will deposit debris in blood vessel walls (atherosclerosis leading to heart attacks and strokes), the brain (amyloid proteins leading to Alzheimer's disease), and retina (lipofuscin pigments leading to AMD). These are three common causes of morbidity and mortality in the developed world. The clinical, genetic, and immunopathologic understandings derived from the two examples of aHUS and AMD may illustrate what to anticipate in related conditions. They highlight how a powerful recognition and effector system, the alternative complement pathway, reacts to altered self. A response to acute injury or chronic debris accumulation must be appropriately balanced. In either case, too much activation or too little regulation promotes undesirable tissue damage and human disease.
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Affiliation(s)
- Anna Richards
- Washington University School of Medicine, St. Louis, Missouri, USA
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752
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de Jorge EG, Harris CL, Esparza-Gordillo J, Carreras L, Arranz EA, Garrido CA, López-Trascasa M, Sánchez-Corral P, Morgan BP, de Córdoba SR. Gain-of-function mutations in complement factor B are associated with atypical hemolytic uremic syndrome. Proc Natl Acad Sci U S A 2006; 104:240-5. [PMID: 17182750 PMCID: PMC1765442 DOI: 10.1073/pnas.0603420103] [Citation(s) in RCA: 340] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hemolytic uremic syndrome (HUS) is an important cause of acute renal failure in children. Mutations in one or more genes encoding complement-regulatory proteins have been reported in approximately one-third of nondiarrheal, atypical HUS (aHUS) patients, suggesting a defect in the protection of cell surfaces against complement activation in susceptible individuals. Here, we identified a subgroup of aHUS patients showing persistent activation of the complement alternative pathway and found within this subgroup two families with mutations in the gene encoding factor B (BF), a zymogen that carries the catalytic site of the complement alternative pathway convertase (C3bBb). Functional analyses demonstrated that F286L and K323E aHUS-associated BF mutations are gain-of-function mutations that result in enhanced formation of the C3bBb convertase or increased resistance to inactivation by complement regulators. These data expand our understanding of the genetic factors conferring predisposition to aHUS, demonstrate the critical role of the alternative complement pathway in the pathogenesis of aHUS, and provide support for the use of complement-inhibition therapies to prevent or reduce tissue damage caused by dysregulated complement activation.
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Affiliation(s)
- Elena Goicoechea de Jorge
- *Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Claire L. Harris
- Department of Medical Biochemistry and Immunology, School of Medicine, Cardiff University, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Jorge Esparza-Gordillo
- *Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Luis Carreras
- Servicio de Nefrología, Hospital Universitario de Bellvitge, Feixa Llarga s/n 08907 Barcelona, Spain; and
| | - Elena Aller Arranz
- *Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain
| | | | | | | | - B. Paul Morgan
- Department of Medical Biochemistry and Immunology, School of Medicine, Cardiff University, Henry Wellcome Building, Heath Park, Cardiff CF14 4XN, United Kingdom
| | - Santiago Rodríguez de Córdoba
- *Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu 9, 28040 Madrid, Spain
- To whom correspondence should be addressed. E-mail:
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753
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Affiliation(s)
- Lon R Cardon
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK.
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754
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Yeoh J, Sims J, Guymer RH. A review of drug options in age-related macular degeneration therapy and potential new agents. Expert Opin Pharmacother 2006; 7:2355-68. [PMID: 17109611 DOI: 10.1517/14656566.7.17.2355] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of legal blindness in people > 50 years of age in the developed world. AMD is both a debilitating and costly disease for the individual and the community. Greater understanding of the mechanisms and pathways involved in causing the visual loss in AMD has resulted in the advent of several newer and more effective treatment options, making it an exciting time in the management of AMD. This paper will examine the principles behind the existing drug therapies available, as well as those being developed in the management or prophylaxis of AMD and its vision-threatening complications.
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Affiliation(s)
- Jonathan Yeoh
- Centre for Eye Research Australia, The University of Melbourne, Australia
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755
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Wang JJ. Genetic and modifiable risk factors for age-related macular degeneration. EXPERT REVIEW OF OPHTHALMOLOGY 2006. [DOI: 10.1586/17469899.1.2.181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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756
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Abstract
Recent experience with several high-profile drugs demonstrates the great challenges in developing effective and safe therapeutics. A complementary approach to the popular paradigm of disease genetics is based on inherited factors that reduce the incidence and severity of disease among individuals who are genetically predisposed to disease. We propose testing specifically for modifier genes and protective alleles among at-risk individuals and studying the efficacy of therapeutics based on the genetics of health.
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Affiliation(s)
- Joseph H Nadeau
- Department of Genetics, Case Western Reserve University School of Medicine, 2109 Adelbert Road, Cleveland, Ohio 44106, USA.
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757
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Bando H, Shadrach KG, Rayborn ME, Crabb JW, Hollyfield JG. Clathrin and adaptin accumulation in drusen, Bruch's membrane and choroid in AMD and non-AMD donor eyes. Exp Eye Res 2006; 84:135-42. [PMID: 17097084 DOI: 10.1016/j.exer.2006.09.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Revised: 09/11/2006] [Accepted: 09/14/2006] [Indexed: 11/24/2022]
Abstract
Clathrin was identified in a recent proteomic analysis of Bruch's membrane from age-related macular degeneration (AMD) donor eyes. The present study was conducted to determine the localization of clathrin in AMD tissues and to compare this distribution and relative content with that in non-AMD control tissues. The distribution of adaptin, which is functionally linked to clathrin, was also evaluated. Human eyes were from donors between 66 and 94 years of age; 13 eyes were from donors with AMD and 13 from non-AMD donors. Bruch's membrane and choroid from the macula of each donor eye were prepared for immunohistochemistry and Western blotting. Differences in immunoreactivity were quantitated. Drusen, Bruch's membrane and choroid from AMD tissues showed greater immunoreactivity for clathrin and adaptin than did non-AMD tissues. Western blots also showed more intense clathrin and adaptin immunoreactivity in AMD tissues than were present in non-AMD samples. This study suggests that accumulation of clathrin and adaptin in drusen, Bruch's membrane and choroid may reflect a higher rate of clathrin mediated endocytosis in AMD tissues. Alternatively, the accumulation of these proteins in these extracellular compartments may reflect a higher susceptibility to oxidative damage.
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Affiliation(s)
- Hajime Bando
- Cole Eye Institute (i-31), Department of Ophthalmology, Cleveland Clinic Foundation Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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758
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Yang Z, Camp NJ, Sun H, Tong Z, Gibbs D, Cameron DJ, Chen H, Zhao Y, Pearson E, Li X, Chien J, Dewan A, Harmon J, Bernstein PS, Shridhar V, Zabriskie NA, Hoh J, Howes K, Zhang K. A variant of the HTRA1 gene increases susceptibility to age-related macular degeneration. Science 2006; 314:992-3. [PMID: 17053109 DOI: 10.1126/science.1133811] [Citation(s) in RCA: 523] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Age-related macular degeneration (AMD) is the most common cause of irreversible vision loss in the developed world and has a strong genetic predisposition. A locus at human chromosome 10q26 affects the risk of AMD, but the precise gene(s) have not been identified. We genotyped 581 AMD cases and 309 normal controls in a Caucasian cohort in Utah. We demonstrate that a single-nucleotide polymorphism, rs11200638, in the promoter region of HTRA1 is the most likely causal variant for AMD at 10q26 and is estimated to confer a population attributable risk of 49.3%. The HTRA1 gene encodes a secreted serine protease. Preliminary analysis of lymphocytes and retinal pigment epithelium from four AMD patients revealed that the risk allele was associated with elevated expression levels of HTRA1 mRNA and protein. We also found that drusen in the eyes of AMD patients were strongly immunolabeled with HTRA1 antibody. Together, these findings support a key role for HTRA1 in AMD susceptibility and identify a potential new pathway for AMD pathogenesis.
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Affiliation(s)
- Zhenglin Yang
- Department of Ophthalmology and Visual Sciences, Moran Eye Center, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
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759
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Frank J, Di Ruggiero E, McInnes RR, Kramer M, Gagnon F. Large Life-Course Cohorts for Characterizing Genetic and Environmental Contributions. Epidemiology 2006; 17:595-8. [PMID: 17068411 DOI: 10.1097/01.ede.0000239725.48908.7d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- John Frank
- Department of Public Health Sciences, University of Toronto, Toronto, Canada.
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760
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Johnson PT, Betts KE, Radeke MJ, Hageman GS, Anderson DH, Johnson LV. Individuals homozygous for the age-related macular degeneration risk-conferring variant of complement factor H have elevated levels of CRP in the choroid. Proc Natl Acad Sci U S A 2006; 103:17456-61. [PMID: 17079491 PMCID: PMC1859950 DOI: 10.1073/pnas.0606234103] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Polymorphisms in the complement factor H gene (CFH) are associated with a significantly increased risk for, or protection against, the development of age-related macular degeneration (AMD). The most documented risk-conferring single-nucleotide polymorphism results in a tyrosine-to-histidine substitution at position 402 (Y402H) of the CFH protein. In this work, we examined the ocular distributions and relative abundance of CFH, several CFH-binding proteins, and abundant serum proteins in the retinal pigmented epithelium (RPE), Bruch's membrane, and choroid (RPE-choroid) in CFH homozygotes possessing either the "at-risk" 402HH or "normal" 402YY variants. Although CFH immunoreactivity is high in the choroid and in drusen, no differences in CFH-labeling patterns between genotypes are apparent. In contrast, at-risk individuals have significantly higher levels of the CFH-binding protein, C-reactive protein (CRP), in the choroidal stroma. Immunoblots confirm that at-risk individuals have approximately 2.5-fold higher levels of CRP in the RPE-choroid; no significant differences in the levels of CFH or other serum proteins are detected. Similarly, we find no differences in CFH transcription levels in the RPE-choroid nor evidence for local ocular CRP transcription. Increased levels of CRP in the choroid may reflect a state of chronic inflammation that is a by-product of attenuated CFH complement-inhibitory activity in those who possess the CFH at-risk allele. Because the CRP-binding site in CFH lies within the domain containing the Y402H polymorphism, it is also possible that the AMD risk-conferring allele alters the binding properties of CFH, thereby leading to choroidal CRP deposition, contributing to AMD pathogenesis.
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Affiliation(s)
- P. T. Johnson
- *Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA 93106-5060; and
- To whom correspondence should be addressed. E-mail:
| | - K. E. Betts
- *Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA 93106-5060; and
| | - M. J. Radeke
- *Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA 93106-5060; and
| | - G. S. Hageman
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA 52242
| | - D. H. Anderson
- *Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA 93106-5060; and
| | - L. V. Johnson
- *Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA 93106-5060; and
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761
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Rohrer B, Demos C, Frigg R, Grimm C. Classical complement activation and acquired immune response pathways are not essential for retinal degeneration in the rd1 mouse. Exp Eye Res 2006; 84:82-91. [PMID: 17069800 PMCID: PMC1885545 DOI: 10.1016/j.exer.2006.08.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Revised: 08/21/2006] [Accepted: 08/25/2006] [Indexed: 11/17/2022]
Abstract
Misregulation of the innate immune response and other immune-related processes have been suggested to play a critical role in the pathogenesis of a number of different neurodegenerative diseases, including age related macular degeneration. In an animal model for photoreceptor degeneration, several genes of the innate and acquired immune system were found to be differentially regulated in the retina during the degenerative process. In addition to this differential regulation of individual genes, we found that in the rd1 retina a significantly higher number of genes involved in immune-related responses were expressed at any given time during the degenerative period. The peak of immune-related gene expression was at postnatal day 14, coinciding with the peak of photoreceptor apoptosis in the rd1 mouse. We directly tested the potential involvement of acquired and innate immune responses in initiation and progression of photoreceptor degeneration by analyzing double mutant animals. Retinal morphology and photoreceptor apoptosis of rd1 mice on a SCID genetic background (no mature T- and B-cells) or in combination with a RAG1 (no functional B- and T-cells) or a C1qalpha (no functional classical complement activation pathway) knockout was followed during the degenerative process using light microscopy or TUNEL staining, respectively. Although complement factor C1qalpha was highly up-regulated in the rd1 retina concomitantly with the degenerative process, lack of this protein did not protect the rd1 retina. Similarly, retinal degeneration and photoreceptor apoptosis appeared to proceed normally in the rd1 mouse lacking functional B- and T-cells. Our results suggest that both, the classical complement system of innate immunity and a functional acquired immune response are not essential for the degenerative process in the rd1 mouse retina.
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Affiliation(s)
- Bärbel Rohrer
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC 29425, USA.
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762
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Zhou J, Jang YP, Kim SR, Sparrow JR. Complement activation by photooxidation products of A2E, a lipofuscin constituent of the retinal pigment epithelium. Proc Natl Acad Sci U S A 2006; 103:16182-7. [PMID: 17060630 PMCID: PMC1637557 DOI: 10.1073/pnas.0604255103] [Citation(s) in RCA: 265] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent studies have implicated local inflammation and activation of complement amongst the processes involved in the pathogenesis of age-related macular degeneration (AMD). Several lines of investigation also indicate that bis-retinoid pigments, such as A2E, that accumulate as lipofuscin in retinal pigment epithelial (RPE) cells, contribute to the disease process. In an investigation of a potential trigger for complement activation in AMD, we explored the notion that the complex mixture of products resulting from photooxidation of A2E might include a range of fragments that could be recognized by the complement system as "foreign" and that could serve to activate the complement system, leading to low-grade inflammation. To this end, we established an in vitro assay by using human serum as a source of complement, and we measured products of C3 activation by enzyme immunoassay. Accordingly, we found that the C3 split products inactivated C3b (iC3b) and C3a were elevated in serum, overlying ARPE-19 cells that had accumulated A2E and were irradiated to induce A2E photooxidation. Precoating of microtiter plates with two species of oxidized A2E, peroxy-A2E, and furano-A2E, followed by incubation with serum, also activated complement. We suggest that products of the photooxidation of bis-retinoid lipofuscin pigments in RPE cells could serve as a trigger for the complement system, a trigger than would predispose the macula to disease and that, over time, could contribute to chronic inflammation. These findings link four factors that have been posited as being associated with AMD: inflammation, oxidative damage, drusen, and RPE lipofuscin.
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Affiliation(s)
| | | | | | - Janet R. Sparrow
- Departments of *Ophthalmology and
- Pathology and Cell Biology, Columbia University, New York, NY 10032
- To whom correspondence should be addressed. E-mail:
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763
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Rattner A, Nathans J. Macular degeneration: recent advances and therapeutic opportunities. Nat Rev Neurosci 2006; 7:860-72. [PMID: 17033682 DOI: 10.1038/nrn2007] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The central retina mediates high acuity vision, and its progressive dysfunction due to macular degeneration is the leading cause of visual disability among adults in industrialized societies. Here, we summarize recent progress in understanding the pathophysiology of macular degeneration and the implications of this new knowledge for treatment and prevention. The past decade has witnessed remarkable advances in this field, including the development of new, non-invasive retinal imaging technologies, the development of animal models for macular disease, and the isolation of many of the genes responsible for both early- and late-onset macular diseases. These advances have set the stage for the development of effective mechanism-based therapies.
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Affiliation(s)
- Amir Rattner
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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764
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Affiliation(s)
- Paulus T V M de Jong
- Department of Ophthalmogenetics, Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, Amsterdam, The Netherlands.
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765
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Oudejans CBM, van Dijk M, Oosterkamp M, Lachmeijer A, Blankenstein MA. Genetics of preeclampsia: paradigm shifts. Hum Genet 2006; 120:607-12. [PMID: 17024365 DOI: 10.1007/s00439-006-0259-1] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 08/31/2006] [Indexed: 11/29/2022]
Abstract
Segregation of preeclampsia into early-onset, placental and late-onset, maternal subtypes along with the acknowledgement of the contribution of epigenetics in placentally expressed genes proved to be a key first step in the identification of essential gene variants associated with preeclampsia. Application of this insight to other populations and related pregnancy-induced syndromes, such as HELLP, and acknowledgment of the features shared between chromosomal loci associated with preeclampsia in different populations provide the rationale for new strategies for the identification of susceptibility genes and for new and more effective diagnostic strategies.
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Affiliation(s)
- Cees B M Oudejans
- Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands.
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766
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767
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Ebrahem Q, Renganathan K, Sears J, Vasanji A, Gu X, Lu L, Salomon RG, Crabb JW, Anand-Apte B. Carboxyethylpyrrole oxidative protein modifications stimulate neovascularization: Implications for age-related macular degeneration. Proc Natl Acad Sci U S A 2006; 103:13480-4. [PMID: 16938854 PMCID: PMC1569188 DOI: 10.1073/pnas.0601552103] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2006] [Indexed: 12/24/2022] Open
Abstract
Choroidal neovascularization (CNV), the advanced stage of age-related macular degeneration (AMD), accounts for >80% of vision loss in AMD. Carboxyethylpyrrole (CEP) protein modifications, uniquely generated from oxidation of docosahexaenoate-containing lipids, are more abundant in Bruch's membrane from AMD eyes. We tested the hypothesis that CEP protein adducts stimulate angiogenesis and possibly contribute to CNV in AMD. Human serum albumin (HSA) or acetyl-Gly-Lys-O-methyl ester (dipeptide) were chemically modified to yield CEP-modified HSA (CEP-HSA) or CEP-dipeptide. The in vivo angiogenic properties of CEP-HSA and CEP-dipeptide were demonstrated by using the chick chorioallantoic membrane and rat corneal micropocket assays. Low picomole amounts of CEP-HSA and CEP-dipeptide stimulated neovascularization. Monoclonal anti-CEP antibody neutralized limbal vessel growth stimulated by CEP-HSA, whereas anti-VEGF antibody was found to only partially neutralize vessel growth. Subretinal injections of CEP-modified mouse serum albumin exacerbated laser-induced CNV in mice. In vitro treatments of human retinal pigment epithelial cells with CEP-dipeptide or CEP-HSA did not induce increased VEGF secretion. Overall, these results suggest that CEP-induced angiogenesis utilizes VEGF-independent pathways and that anti-CEP therapeutic modalities might be of value in limiting CNV in AMD.
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Affiliation(s)
| | - Kutralanathan Renganathan
- *Cole Eye Institute and
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44195
| | | | - Amit Vasanji
- Lerner Research Institute, Cleveland Clinic Foundation, and
| | | | - Liang Lu
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44195
| | - Robert G. Salomon
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44195
| | - John W. Crabb
- *Cole Eye Institute and
- Lerner Research Institute, Cleveland Clinic Foundation, and
- Department of Chemistry, Case Western Reserve University, Cleveland, OH 44195
| | - Bela Anand-Apte
- *Cole Eye Institute and
- Lerner Research Institute, Cleveland Clinic Foundation, and
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768
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Maller J, George S, Purcell S, Fagerness J, Altshuler D, Daly MJ, Seddon JM. Common variation in three genes, including a noncoding variant in CFH, strongly influences risk of age-related macular degeneration. Nat Genet 2006; 38:1055-9. [PMID: 16936732 DOI: 10.1038/ng1873] [Citation(s) in RCA: 417] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Accepted: 08/01/2006] [Indexed: 11/08/2022]
Abstract
Age-related macular degeneration (AMD) is a common, late-onset disease with seemingly typical complexity: recurrence ratios for siblings of an affected individual are three- to sixfold higher than in the general population, and family-based analysis has resulted in only modestly significant evidence for linkage. In a case-control study drawn from a US-based population of European descent, we have identified a previously unrecognized common, noncoding variant in CFH, the gene encoding complement factor H, that substantially increases the influence of this locus on AMD, and we have strongly replicated the associations of four other previously reported common alleles in three genes (P values ranging from 10(-6) to 10(-70)). Despite excellent power to detect epistasis, we observed purely additive accumulation of risk from alleles at these genes. We found no differences in association of these loci with major phenotypic categories of advanced AMD. Genotypes at these five common SNPs define a broad spectrum of interindividual disease risk and explain about half of the classical sibling risk of AMD in our study population.
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Affiliation(s)
- Julian Maller
- Center for Human Genetic Research, Massachusetts General Hospital, 185 Cambridge St., Boston, Massachusetts 02114, USA
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769
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An E, Lu X, Flippin J, Devaney JM, Halligan B, Hoffman EP, Hoffman E, Strunnikova N, Csaky K, Hathout Y. Secreted Proteome Profiling in Human RPE Cell Cultures Derived from Donors with Age Related Macular Degeneration and Age Matched Healthy Donors. J Proteome Res 2006; 5:2599-610. [PMID: 17022631 DOI: 10.1021/pr060121j] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Age-related macular degeneration (AMD) is characterized by progressive loss of central vision, which is attributed to abnormal accumulation of macular deposits called "drusen" at the interface between the basal surface of the retinal pigment epithelium (RPE) and Bruch's membrane. In the most severe cases, drusen deposits are accompanied by the growth of new blood vessels that breach the RPE layer and invade photoreceptors. In this study, we hypothesized that RPE secreted proteins are responsible for drusen formation and choroidal neovascularization. We used stable isotope labeling by amino acids in cell culture (SILAC) in combination with LC-MS/MS analysis and ZoomQuant quantification to assess differential protein secretion by RPE cell cultures prepared from human autopsy eyes of AMD donors (diagnosed by histological examinations of the macula and genotyped for the Y402H-complement factor H variant) and age-matched healthy control donors. In general, RPE cells were found to secrete a variety of extracellular matrix proteins, complement factors, and protease inhibitors that have been reported to be major constituents of drusen (hallmark deposits in AMD). Interestingly, RPE cells from AMD donors secreted 2 to 3-fold more galectin 3 binding protein, fibronectin, clusterin, matrix metalloproteinase-2 and pigment epithelium derived factor than RPE cells from age-matched healthy donors. Conversely, secreted protein acidic and rich in cysteine (SPARC) was found to be down regulated by 2-fold in AMD RPE cells versus healthy RPE cells. Ingenuity pathway analysis grouped these differentially secreted proteins into two groups; those involved in tissue development and angiogenesis and those involved in complement regulation and protein aggregation such as clusterin. Overall, these data strongly suggest that RPE cells are involved in the biogenesis of drusen and the pathology of AMD.
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Affiliation(s)
- Eunkyung An
- Center for Genetic Medicine, Children's National Medical Center, and Program in Biochemistry and Molecular Genetics, Institute of Biomedical Science, The George Washington University, Washington, DC, USA
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770
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Bora NS, Kaliappan S, Jha P, Xu Q, Sohn JH, Dhaulakhandi DB, Kaplan HJ, Bora PS. Complement Activation via Alternative Pathway Is Critical in the Development of Laser-Induced Choroidal Neovascularization: Role of Factor B and Factor H. THE JOURNAL OF IMMUNOLOGY 2006; 177:1872-8. [PMID: 16849499 DOI: 10.4049/jimmunol.177.3.1872] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The objective of this study was to explore the role of classical, lectin, and alternative pathways of complement activation in laser-induced choroidal neovascularization (CNV). The classical and alternative pathways were blocked in C57BL/6 mice by small interfering RNAs (siRNA) directed against C1q and factor B, respectively. C4(-/-) mice developed CNV similar to their wild-type controls and inhibition of C1q by siRNA had no effect on the development of CNV. In contrast, CNV was significantly inhibited (p < 0.001) in C5(-/-) mice and C57BL/6 mice treated with factor B siRNA. Inhibition of the alternative pathway by factor B siRNA resulted in decreased levels of membrane attack complex and angiogenic factors-vascular endothelial growth factor and TGF-beta2. Furthermore, factor B was up-regulated in complement sufficient C57BL/6 mice at day 1 postlaser and remained elevated at day 7. Significantly reduced levels of factor H were observed at day 3 in these animals. In conclusion, our results demonstrate that activation of the factor B-dependent alternative pathway, but not the classical or lectin pathways, was essential for the development of CNV in mouse model of laser-induced CNV. Thus, specific blockade of the alternative pathway may represent a therapeutically relevant strategy for the inhibition of CNV.
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Affiliation(s)
- Nalini S Bora
- Department of Ophthalmology, Jones Eye Institute, Pat and Willard Walker Eye Research Center, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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771
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Haddad S, Chen CA, Santangelo SL, Seddon JM. The Genetics of Age-Related Macular Degeneration: A Review of Progress to Date. Surv Ophthalmol 2006; 51:316-63. [PMID: 16818082 DOI: 10.1016/j.survophthal.2006.05.001] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of vision loss and blindness among older adults in the USA and throughout the developed world. Etiological research suggests that AMD is a complex disease, caused by the actions and interactions of multiple genes and environmental factors. Familial aggregation studies, twin studies, and segregation analyses have provided strong evidence for the heritability of AMD, and linkage and association studies have been conducted to localize the disease-causing genes. Whole genome linkage scans have implicated nearly every chromosome in the human genome, with the most replicated signals residing on 1q25-31 and 10q26. Association studies have identified a major risk variant within the complement factor H gene (CFH), and recent reports suggest that PLEKHA1/LOC387715 and the BF/C2 regions may be major risk loci for AMD as well. Several other genes have had at least one positive association finding and deserve further exploration. Among these, apolipoprotein E (APOE) may be a minor risk locus. Additional genes will likely be identified, and future studies should explore the potential interactions of these genes with other genes as well as environmental factors.
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Affiliation(s)
- Stephen Haddad
- Psychiatric and Neurodevelopmental Genetics Unit, Massachusetts General Hospital, Boston, 02114, USA
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772
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Gotoh N, Yamada R, Hiratani H, Renault V, Kuroiwa S, Monet M, Toyoda S, Chida S, Mandai M, Otani A, Yoshimura N, Matsuda F. No association between complement factor H gene polymorphism and exudative age-related macular degeneration in Japanese. Hum Genet 2006; 120:139-43. [PMID: 16710702 DOI: 10.1007/s00439-006-0187-0] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2005] [Accepted: 04/10/2006] [Indexed: 11/27/2022]
Abstract
Age-related macular degeneration (ARMD) is the leading cause of blindness in the elderly population not only Western but also Asian industrial countries. In Caucasian, a polymorphism of the complement factor H gene (CFH), the C allele of rs1061170 (Y402H), was established as the first strong genetic factor for excursively exudative type of ARMD. In this study, we performed an extensive sequencing of the 22 exons in the CFH gene by recruiting 146 exudative ARMD patients and 105 normal controls of Japanese origin and identified 61 polymorphisms. We found that the frequency of the C allele of rs1061170 (Y402H) is much lower (0.04) in Japanese controls than in Caucasians (0.45). No case disease susceptibility to exudative ARMD was noted for rs1061170 (Y402H) (chi (2) = 3.19, P (corr) = 0.423), or other 12 single nucleotide polymorphisms (SNPs) whose frequency is greater than 0.05. When haplotypes were inferred for 13 SNPs (these 12 SNPs with a frequency greater than 0.05 and rs1061170), three haplotypes whose pattern was similar to those in Caucasians were identified but with substantial difference in frequency. Again we failed to identify genetic association between Japanese exudative ARMD and any of the haplotypes including the J1 haplotype which was shown to be susceptible to ARMD in Caucasians (chi (2 )=( )3.92, P (corr) = 0.157). CFH does not appear to be a primary hereditary contributor to ARMD in Japanese. The absence of CFH contribution to ARMD in Japanese may correlate with the findings in ethnic differences of ARMD phenotypes.
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Affiliation(s)
- Norimoto Gotoh
- Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan
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773
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Bazan NG. Cell survival matters: docosahexaenoic acid signaling, neuroprotection and photoreceptors. Trends Neurosci 2006; 29:263-71. [PMID: 16580739 DOI: 10.1016/j.tins.2006.03.005] [Citation(s) in RCA: 265] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2005] [Revised: 02/24/2006] [Accepted: 03/16/2006] [Indexed: 11/26/2022]
Abstract
Recent data have provided important clues about the molecular mechanisms underlying certain retinal degenerative diseases, including retinitis pigmentosa and age-related macular degeneration. Photoreceptor cell degeneration is a feature common to these diseases, and the death of these cells in many instances seems to involve the closely associated retinal pigment epithelial (RPE) cells. Under normal circumstances, both cell types are subject to potentially damaging stimuli (e.g. sunlight and high oxygen tension). However, the mechanism or mechanisms by which homeostasis is maintained in this part of the eye, which is crucial for sight, are an unsolved riddle. The omega-3 fatty acid family member docosahexaenoic acid (DHA), which is enriched in these cells, is the precursor of neuroprotectin D1 (NPD1). NPD1 inhibits oxidative-stress-mediated proinflammatory gene induction and apoptosis, and consequently promotes RPE cell survival. This enhanced understanding of the molecular basis of endogenous anti-inflammatory and neuroprotective signaling in the RPE presents an opportunity for the development of therapies for retinal degenerative diseases.
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Affiliation(s)
- Nicolas G Bazan
- LSU Neuroscience Center of Excellence and Department of Ophthalmology, Louisiana State University Health Sciences Center School of Medicine in New Orleans, LA 70112, USA.
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774
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Imamura Y, Ishida S, Tsubota K. Current concept of the pathogenesis of age-related macular degeneration: the role of oxidative stress and inflammation. Inflamm Regen 2006. [DOI: 10.2492/inflammregen.26.492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Yutaka Imamura
- Department of Ophthalmology, Keio University School of Medicine
| | - Susumu Ishida
- Department of Ophthalmology, Keio University School of Medicine
| | - Kazuo Tsubota
- Department of Ophthalmology, Keio University School of Medicine
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775
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Gehrs KM, Anderson DH, Johnson LV, Hageman GS. Age-related macular degeneration--emerging pathogenetic and therapeutic concepts. Ann Med 2006; 38:450-71. [PMID: 17101537 PMCID: PMC4853957 DOI: 10.1080/07853890600946724] [Citation(s) in RCA: 452] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Today, the average life expectancy in developed nations is over 80 years and climbing. And yet, the quality of life during those additional years is often significantly diminished by the effects of age-related, degenerative diseases, including age-related macular degeneration (AMD), the leading cause of blindness in the elderly worldwide. AMD is characterized by a progressive loss of central vision attributable to degenerative and neovascular changes in the macula, a highly specialized region of the ocular retina responsible for fine visual acuity. Estimates gathered from the most recent World Health Organization (WHO) global eye disease survey conservatively indicate that 14 million persons are blind or severely visually impaired because of AMD. The disease has a tremendous impact on the physical and mental health of the geriatric population and their families and is becoming a major public health burden. Currently, there is neither a cure nor a means to prevent AMD. Palliative treatment options for the less prevalent, late-stage 'wet' form of the disease include anti-neovascular agents, photodynamic therapy and thermal laser. There are no current therapies for the more common 'dry' AMD, except for the use of antioxidants that delay progression in 20%-25% of eyes. New discoveries, however, are beginning to provide a much clearer picture of the relevant cellular events, genetic factors, and biochemical processes associated with early AMD. Recently, compelling evidence has emerged that the innate immune system and, more specifically, uncontrolled regulation of the complement alternative pathway plays a central role in the pathobiology of AMD. The complement Factor H gene--which encodes the major inhibitor of the complement alternative pathway--is the first gene identified in multiple independent studies that confers a significant genetic risk for the development of AMD. The emergence of this new paradigm of AMD pathogenesis should hasten the development of novel diagnostic and therapeutic approaches for this disease that will dramatically improve the quality of our prolonged lifespan.
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Affiliation(s)
- Karen M Gehrs
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, IA 52240, USA
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776
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Hageman GS, Hancox LS, Taiber AJ, Gehrs KM, Anderson DH, Johnson LV, Radeke MJ, Kavanagh D, Richards A, Atkinson J, Meri S, Bergeron J, Zernant J, Merriam J, Gold B, Allikmets R, Dean M. Extended haplotypes in the complement factor H (CFH) and CFH-related (CFHR) family of genes protect against age-related macular degeneration: characterization, ethnic distribution and evolutionary implications. Ann Med 2006; 38:592-604. [PMID: 17438673 PMCID: PMC1905836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/20/2023] Open
Abstract
BACKGROUND Variants in the complement factor H gene (CFH) are associated with age-related macular degeneration (AMD). CFH and five CFH-related genes (CFHR1-5) lie within the regulators of complement activation (RCA) locus on chromosome 1q32. Aims and Methods. In this study, the structural and evolutionary relationships between these genes and AMD was refined using a combined genetic, molecular and immunohistochemical approach. RESULTS We identify and characterize a large, common deletion that encompasses both the CFHR1 and CFHR3 genes. CFHR1, an abundant serum protein, is absent in subjects homozygous for the deletion. Genotyping analyses of AMD cases and controls from two cohorts demonstrates that deletion homozygotes comprise 1.1% of cases and 5.7% of the controls (chi-square=32.8; P= 1.6 E-09). CFHR1 and CFHR3 transcripts are abundant in liver, but undetectable in the ocular retinal pigmented epithelium/choroid complex. AMD-associated CFH/CFHR1/CFHR3 haplotypes are widespread in human populations. CONCLUSION The absence of CFHR1 and/or CFHR3 may account for the protective effects conferred by some CFH haplotypes. Moreover, the high frequencies of the 402H allele and the delCFHR1/CFHR3 alleles in African populations suggest an ancient origin for these alleles. The considerable diversity accumulated at this locus may be due to selection, which is consistent with an important role for the CFHR genes in innate immunity.
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Affiliation(s)
- Gregory S. Hageman
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
- Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA
| | - Lisa S. Hancox
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Andrew J. Taiber
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Karen M. Gehrs
- Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Don H. Anderson
- Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA
- Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - Lincoln V. Johnson
- Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA
- Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - Monte J. Radeke
- Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA
- Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - David Kavanagh
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Anna Richards
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - John Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Seppo Meri
- Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | | | - Jana Zernant
- Department of Ophthalmology, Columbia University, New York, New York
| | - Joanna Merriam
- Department of Ophthalmology, Columbia University, New York, New York
| | - Bert Gold
- Laboratory of Genomic Diversity, National Cancer Institute, NCI-Frederick, Frederick, Maryland
| | - Rando Allikmets
- Department of Ophthalmology, Columbia University, New York, New York
- Department of Pathology and Cell Biology, Columbia University, New York, New York
| | - Michael Dean
- Laboratory of Genomic Diversity, National Cancer Institute, NCI-Frederick, Frederick, Maryland
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777
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Ronan S, Nusinowitz S, Swaroop A, Heckenlively JR. Senile panretinal cone dysfunction in age-related macular degeneration (AMD): a report of 52 amd patients compared to age-matched controls. TRANSACTIONS OF THE AMERICAN OPHTHALMOLOGICAL SOCIETY 2006; 104:232-40. [PMID: 17471344 PMCID: PMC1809916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
PURPOSE To test if patients with age-related macular degeneration (AMD) have normal panretinal function using standardized full-field electroretinograms (ERGs). METHODS This is a retrospective study evaluating electroretinographic studies performed in patients with AMD to assess their panretinal function. Fifty-two individuals 55 years or older had standardized ERG testing and fundus photographs. RESULTS The study group was aged 57 to 93 years old with a mean of 75.7, and the controls ranged from 79 to 87 years with a mean of 81.4. On average, the photopic, scotopic, dark-adapted bright-flash, and flicker function response amplitudes are lower with longer implicit times in the study group than the controls. The most pronounced differences were seen with the bright-flash dark-adapted a-waves and the photopic b-wave amplitudes. Forty-three of 104 eyes had abnormal photopic b-wave ERGs of more than 2 SD compared to controls. The mean of the photopic b-wave amplitudes for the study group was 76.7 +/- 36.2 muV (1 SD) compared to 91.4 +/- 16.9 muV (1 SD) for the control group. This finding was statistically significant with P = .0269 by the Student t test and P = .0336 by the Wilcoxon test. CONCLUSIONS There is a subgroup of AMD patients with a panretinal cone dysfunction on ERG in association with their macular degeneration. Previous studies have shown varied results when looking at ERG changes in AMD, likely reflecting the underlying complexity of this disorder. Using standardized ERG to identify a more homogeneous subgroup of AMD patients with panretinal dysfunction will aid in better characterizing subtypes clinically and is likely to be valuable in identifying new genes contributing to AMD.
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Affiliation(s)
- Shawn Ronan
- Department of Ophthalmology and Visual Science, Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, USA
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778
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Hageman GS, Hancox LS, Taiber AJ, Gehrs KM, Anderson DH, Johnson LV, Radeke MJ, Kavanagh D, Richards A, Atkinson J, Meri S, Bergeron J, Zernant J, Merriam J, Gold B, Allikmets R, Dean M. Extended haplotypes in the complement factor H (CFH) and CFH-related (CFHR) family of genes protect against age-related macular degeneration: Characterization, ethnic distribution and evolutionary implications. Ann Med 2006; 38:592-604. [PMID: 28950782 DOI: 10.1080/07853890601097030] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Variants in the complement factor H gene (CFH) are associated with age-related macular degeneration (AMD). CFH and five CFH-related genes (CFHR1-5) lie within the regulators of complement activation (RCA) locus on chromosome 1q32. AIMS AND METHODS In this study, the structural and evolutionary relationships between these genes and AMD was refined using a combined genetic, molecular and immunohistochemical approach. RESULTS We identify and characterize a large, common deletion that encompasses both the CFHR1 and CFHR3 genes. CFHR1, an abundant serum protein, is absent in subjects homozygous for the deletion. Genotyping analyses of AMD cases and controls from two cohorts demonstrates that deletion homozygotes comprise 1.1% of cases and 5.7% of the controls (chi-square = 32.8; P = 1.6 E-09). CFHR1 and CFHR3 transcripts are abundant in liver, but undetectable in the ocular retinal pigmented epithelium/choroid complex. AMD-associated CFH/CFHR1/CFHR3 haplotypes are widespread in human populations. CONCLUSION The absence of CFHR1 and/or CFHR3 may account for the protective effects conferred by some CFH haplotypes. Moreover, the high frequencies of the 402H allele and the delCFHR1/CFHR3 alleles in African populations suggest an ancient origin for these alleles. The considerable diversity accumulated at this locus may be due to selection, which is consistent with an important role for the CFHR genes in innate immunity.
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Affiliation(s)
- Gregory S Hageman
- a Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa.,b Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA
| | - Lisa S Hancox
- a Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Andrew J Taiber
- a Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Karen M Gehrs
- a Department of Ophthalmology and Visual Sciences, The University of Iowa, Iowa City, Iowa
| | - Don H Anderson
- b Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA.,c Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - Lincoln V Johnson
- b Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA.,c Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - Monte J Radeke
- b Center for the Study of Macular Degeneration, University of California, Santa Barbara, CA.,c Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - David Kavanagh
- d Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO
| | - Anna Richards
- d Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO
| | - John Atkinson
- d Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St Louis, MO
| | - Seppo Meri
- e Department of Bacteriology and Immunology, Haartman Institute, University of Helsinki, Helsinki, Finland
| | | | - Jana Zernant
- h Department of Ophthalmology, Columbia University, New York
| | - Joanna Merriam
- h Department of Ophthalmology, Columbia University, New York
| | - Bert Gold
- g Laboratory of Genomic Diversity, National Cancer Institute, NCI-Frederick, Frederick, Maryland
| | - Rando Allikmets
- h Department of Ophthalmology, Columbia University, New York.,i Department of Pathology and Cell Biology, Columbia University, New York
| | - Michael Dean
- g Laboratory of Genomic Diversity, National Cancer Institute, NCI-Frederick, Frederick, Maryland
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