CFH
Complement factor H precursor (H factor 1) [HF] [HF1] [HF2]
Publications[править]
Age-related para-inflammation in the retina-choroidal interface is featured by low-levels of complement activation and subretinal macrophage accumulation. This study aimed to understand how complement expression in macrophages is regulated by retinal pigment epithelium (RPE). Bone marrow-derived macrophages (BMDMs) and RPE cells were cultured from 8-10 weeks old C57BL/6J mice. The BMDMs were co-cultured with normal RPE, or oxidized photoreceptor outer segment (oxPOS) or TNF-α pre-treated RPE, or apoptotic RPE, or RPE-choroid eyecups. Macrophages were then isolated and processed for real-time RT-PCR. The expression of complement inhibitor C1INH in BMDMs was significantly upregulated by RPE and RPE-choroid eyecups. The eyecups also upregulated CFH, CD59a, and Crry in BMDMs. oxPOS pre-treated RPE upregulated C1qb but down-regulated C3 expression in BMDMs. TNF-α pre-treated RPE enhanced C1INH and CFB expression. When BMDMs were treated with apoptotic RPE, the expression of C1qb, CFH, and CD59a was reduced, whereas the expression of C3, CFB and C1INH was increased. Our results suggest that RPE can modulate macrophages complement expression at the retina-choroidal interface even under aging or oxidative conditions. However, during inflammation, they may promote the alternative pathway of complement activation through down-regulating CFH and CD59a and upregulating CFB and C3.
MeSH Terms
- Animals
- Cattle
- Cells, Cultured
- Coculture Techniques
- Complement C1 Inhibitor Protein
- Epithelial Cells
- Macrophages
- Mice
- Photoreceptor Cells, Vertebrate
- Retinal Pigment Epithelium
- Tumor Necrosis Factor-alpha
- Up-Regulation
Keywords
- aging
- complement
- macrophages
- retinal pigment epithelial cells
- subretinal immune privilege
The lack of high-throughput methods to analyze the adipose tissue protein composition limits our understanding of the protein networks responsible for age and diet related metabolic response. We have developed an approach using multiple-dimension liquid chromatography tandem mass spectrometry and extended multiplexing (24 biological samples) with tandem mass tags (TMT) labeling to analyze proteomes of epididymal adipose tissues isolated from mice fed either low or high fat diet for a short or a long-term, and from mice that aged on low [i]versus[/i] high fat diets. The peripheral metabolic health (as measured by body weight, adiposity, plasma fasting glucose, insulin, triglycerides, total cholesterol levels, and glucose and insulin tolerance tests) deteriorated with diet and advancing age, with long-term high fat diet exposure being the worst. In response to short-term high fat diet, 43 proteins representing lipid metabolism ([i]e.g.[/i] AACS, ACOX1, ACLY) and red-ox pathways ([i]e.g.[/i] CPD2, CYP2E, SOD3) were significantly altered (FDR < 10%). Long-term high fat diet significantly altered 55 proteins associated with immune response ([i]e.g.[/i] IGTB2, IFIT3, LGALS1) and rennin angiotensin system ([i]e.g.[/i] ENPEP, CMA1, CPA3, ANPEP). Age-related changes on low fat diet significantly altered only 18 proteins representing mainly urea cycle ([i]e.g.[/i] OTC, ARG1, CPS1), and amino acid biosynthesis ([i]e.g.[/i] GMT, AKR1C6). Surprisingly, high fat diet driven age-related changes culminated with alterations in 155 proteins involving primarily the urea cycle ([i]e.g.[/i] ARG1, CPS1), immune response/complement activation ([i]e.g.[/i] C3, C4b, C8, C9, CFB, CFH, FGA), extracellular remodeling ([i]e.g.[/i] EFEMP1, FBN1, FBN2, LTBP4, FERMT2, ECM1, EMILIN2, ITIH3) and apoptosis ([i]e.g.[/i] YAP1, HIP1, NDRG1, PRKCD, MUL1) pathways. Using our adipose tissue tailored approach we have identified both age-related and high fat diet specific proteomic signatures highlighting a pronounced involvement of arginine metabolism in response to advancing age, and branched chain amino acid metabolism in early response to high fat feeding. Data are available via ProteomeXchange with identifier PXD005953.
MeSH Terms
- Adipose Tissue
- Aging
- Animals
- Diet, High-Fat
- Epididymis
- Gene Regulatory Networks
- Immunoblotting
- Male
- Mass Spectrometry
- Metabolic Networks and Pathways
- Mice, Inbred C57BL
- Proteome
- Proteomics
- Reproducibility of Results
- Sample Size
To briefly review age-related macular degeneration (AMD), the main findings from the Age Related Eye Disease Study (AREDS) report number 8 on the use of nutritional supplements for AMD, and to focus on data suggesting that supplement use should be guided using genetic testing of AMD risk genes. A literature search (January 2001 through October 26, 2016) was conducted using MEDLINE and the following MeSH terms: Antioxidants/therapeutic use, Genotype, Macular Degeneration/drug therapy, Macular degeneration/genetics, Dietary Supplements, Proteins/genetics, and Zinc Compounds/therapeutic use. Bibliographies of publications identified were also reviewed. English-language studies assessing AREDS supplement response in patients with AMD in relation to complement factor H gene ( CFH) and age-related maculopathy susceptibility 2 gene ( ARMS2) risk alleles were evaluated. Three of the 4 studies demonstrated a treatment interaction between ARMS2 and CFH genotypes and a differential response to supplements. The fourth study documented an interaction for the CFH genotype only. Reported response interactions included attenuated response, no response, and good response, whereas a subset showed increased progression of AMD. Conversely, one study reported no interactions between CFH and ARMS2 risk alleles and response to supplements. The weight of the evidence supports using genetic testing to guide selection of ocular vitamin use. This approach will avoid using supplements that could speed the progression of AMD in vulnerable patients, avoid using supplements that will have little to no effect in others, and result in appropriately using supplements in those that are likely to derive meaningful benefits.
MeSH Terms
- Alleles
- Antioxidants
- Complement Factor H
- Dietary Supplements
- Disease Progression
- Dose-Response Relationship, Drug
- Female
- Genotype
- Humans
- Macular Degeneration
- Male
- Middle Aged
- Polymorphism, Single Nucleotide
- Proteins
- Risk Factors
- Treatment Outcome
- Vitamins
Keywords
- Aging
- Drug Safety
- Nutrition
- Opthalmology
- Pharmacogenetics and Pharmacogenomics
Age-related diseases are becoming increasingly prevalent and the burden continues to grow as our population ages. Effective treatments are necessary to lessen the impact of debilitating conditions but remain elusive in many cases. Only by understanding the causes and pathology of diseases associated with aging, can scientists begin to identify potential therapeutic targets and develop strategies for intervention. The most common age-related conditions are neurodegenerative disorders such as Parkinson's disease and blindness. Age-related macular degeneration (AMD) is the leading cause of blindness in the elderly. Genome wide association studies have previously identified loci that are associated with increased susceptibility to this disease and identified two regions of interest: complement factor H (CFH) and the 10q26 locus, where the age-related maculopathy susceptibility 2 (ARMS2) and high-temperature requirement factor A1 (HtrA1) genes are located. CFH acts as a negative regulator of the alternative pathway (AP) of the complement system while HtrA1 is an extracellular serine protease. ARMS2 is located upstream of HtrA1 in the primate genome, although the gene is absent in mice. To study the effects of these genes, humanized knock-in mouse lines of Cfh and ARMS2, knockouts of Cfh, HtrA1, HtrA2, HtrA3 and HtrA4 as well as a conditional neural deletion of HtrA2 were generated. Of all the genetically engineered mice produced only mice lacking HtrA2, either systemically or in neural tissues, displayed clear phenotypes. In order to examine these mice thoroughly and systematically, an initial phenotyping schedule was established, consisting of a series of tests related to two main diseases of interest: AMD and Parkinson's. Genetically modified mice can be subjected to appropriate experiments to identify phenotypes that may be related to the associated diseases in humans. A phenotyping regimen with a mitochondrial focus is presented here alongside representative results from the tests of interest.
MeSH Terms
- Aging
- Animals
- Complement Factor H
- Disease Models, Animal
- Gene Knock-In Techniques
- Genotype
- High-Temperature Requirement A Serine Peptidase 1
- Humans
- Mice
- Mice, Knockout
- Mice, Transgenic
- Phenotype
- Polymorphism, Single Nucleotide
- Proteins
- Serine Endopeptidases
To determine whether decreasing illumination of the Pelli-Robson contrast sensitivity (CS) chart and MP-1 microperimeter to low mesopic conditions is more sensitive to vision changes occurring with healthy ageing and in early and intermediate age-related macular degeneration (AMD) and whether these mesopic tests can differentiate visual function between healthy older participants with and without AMD risk genotypes. Retinal sensitivity was measured in 98 healthy participants (19-85 years) and 21 AMD (AREDS Grade 2/3) patients (73.9 ± 6.5 years) using the Pelli-Robson CS chart and MP-1 microperimeter under low mesopic and standard illumination. The effect of ageing and AMD on retinal sensitivity was estimated using regression analysis. Healthy older participants (>50 years; n = 24) were genotyped for AMD risk genes CFH and/or ARMS2 and retinal sensitivity was compared between genotypes. With healthy ageing, photopic and mesopic Pelli-Robson CS showed a similar decline (-0.004 log CS/year). In AMD, photopic CS showed a similar decline to healthy ageing (-0.004 log CS/year) while mesopic CS was significantly reduced (-0.007 log CS/year). Both standard and low mesopic microperimetry showed a significant decline (-0.51 and -0.73% contrast/year) with healthy ageing and greater decline (-0.73 and -0.99% contrast/year) with AMD onset. Pelli-Robson CS and microperimetry sensitivity did not differ between AMD risk genotypes in healthy participants. Mesopic Pelli-Robson CS detects functional deficits before photopic CS in early and intermediate AMD that can be differentiated from ageing. This test can be easily administered in clinical practice and may provide a means for early detection of retinal dysfunction.
MeSH Terms
- Adult
- Aged
- Aged, 80 and over
- Aging
- Complement Factor H
- Contrast Sensitivity
- Female
- Genotype
- Healthy Volunteers
- Humans
- Macular Degeneration
- Male
- Mesopic Vision
- Middle Aged
- Proteins
- Retina
- Vision Tests
- Visual Field Tests
- Visual Fields
- Young Adult
Keywords
- contrast sensitivity
- macular degeneration
- mesopic
- microperimetry
Age-related macular degeneration (AMD) in the Japanese often shows different clinical features from those described in Caucasians. For example, we often observe choroidal neovascularization (CNV) in elderly patients without drusen in the fundus. The high incidence of polypoidal choroidal vasculopathy (PCV) in AMD among Japanese is well-known. The reason why such differences occur in clinical manifestations of AMD has been one of my main interests. In this review article, I will discuss the characteristics of AMD in the Japanese population, as found in our recent study. I. Prevalence and clinical characteristics of AMD in the Japanese population. Cohort studies are important to determine the prevalence and incidence of diseases. In Japan, cohort studies began to be carried out rather late compared with Western countries. Although good cohort studies from Japan are reported in the literature, the size of the cohorts was not sufficiently large to determine the prevalence of AMD. However, a recent meta-analysis of Asian cohorts has shown that the prevalence of late AMD in Asians is not different from that reported in Caucasians. On the other hand, the prevalence of early AMD appears lower in the Japanese than in Caucasians. Recently, we have published the results of the Nagahama Cohort study. In this cohort study, we found a high prevalence of drusen. It seems that the incidence of dry AMD is likely to increase among Japanese. In Japan, most retina specialists classify AMD into three categories : typical AMD, PCV, and retinal angiomatous proliferation (RAP). However, there are no definite diagnostic criteria to distinguish between the three conditions. To compare the clinical features of Japanese and Western cases of AMD, and to determine the incidence of the three types of AMD, we exchanged data about 100 consecutive cases between Kyoto University and Centre d'Ophtalmologie de Paris, France. Interestingly, the diagnoses made by the two institutes were not always in agreement. We also found more cases of PCV among the Japanese than among the French. II. PCV. About 50% of exudative AMD cases in the Japanese population are PCV. Because of its peculiar angiographic findings, PCV has long been considered to be a distinct clinical entity different from the usual exudative AMD. Also, there have been serious discussions on the nature of PCV. In our analyses, about 20% of PCV cases show rather large lesion sizes that exceed the vascular arcade. Scar formation in the macula and compromised vision are frequent findings in such cases. The occurrence of PCV in the inferior staphyloma or in angioid streaks shows heterogeneity in PCV. These findings suggest that PCV may be a finding on indocyanine green angiography rather than a distinct clinical entity. Spectral domain OCT examination shows that the branching vascular network of PCV is located between the retinal pigment epithelium and Bruch's membrane. In cases with retinal pigment epithelial detachment, CNV from the branching vascular network was found to extend along the roof of the detached retinal pigment epithelium. Such findings show that the branching vascular network of PCV is type 1 CNV. Complement factor H (CFH) and age-related maculopathy 2 (ARMS2)/High temperature requirement 1 (HTRA1) located on chromosome 10 (10q26) are well-established disease susceptible genes of AMD. In the Japanese, the prevalence of CFH Y402H gene polymorphism is low and ARMS2/HITRA1 plays a more important role in the development of AMD. In ARMS2 A69S polymorphism, a large deletion/insertion (443de1/54ins) that is reported in Caucasians was also found in Japanese. Thus, the genetic background of Caucasian and Japanese AMD is quite similar, as is also the case with exudative AMD and PCV. Our findings show that PCV is not a distinct clinical entity but is a subtype of exudative AMD. III. Exudative AMD with choroidal vascular hyperpermeability. Choroidal vascular hyperpermeability observed in central serous chorioretinopathy can be found in about 20% to 30% of exudative AMD cases in Japanese. Such cases often show a thick choroid, lack of drusen, and rather good visual prognosis with slow progression of the disease. Recently, "pachychoroid neovasculopathy" has been described by a group from New York. Such cases of AMD with choroidal vascular hyperpermeability, a thick choroid, and lack of drusen appears to belong to pachychoroid neovasculopathy. We studied the risk allele frequencies of CFH I62V and ARMS2 A69S gene polymorphisms in three groups : usual exudative AMD, pachychoroid neovasculopathy, and normal controls. Interestingly, cases of pachychoroid neovasculopathy show different gene polymorphisms of CFH I62V and ARMS2 A69S from the usual cases of exudative AMD and a more similar pattern to normal controls. Therefore, the possible mechanisms of the CNV development in such cases may differ from the classic well-documented drusen-dependent pathways. IV. Atrophic AMD in Japanese. Data from the Nagahama Cohort study show an increasing prevalence of drusen in Japanese. Recently, more extensive information on drusen has become available and the redefinition of drusen is currently in progress. In particular, the importance of reticular pseudodrusen (RPD) is more widely appreciated. This type of drusen is often found in Japanese AMD. Although the nature and location of RPD are still debatable, many investigators believe that this type of drusen is located under the sensory retina rather than under Bruch's membrane. In our analyses, RPD was found in 18.4% of late AMD cases in Japanese. It was more common in eyes with RAP or atrophic AMD and was seldom found in PCV. ARMS2 A69S gene polymorphism was found more frequently in cases of exudative AMD with RPD, than in cases of exudative AMD without RPD. Eyes with RPD show a thin choroid and diminished vascular densities of choroidal vessels.
MeSH Terms
- Aging
- Eye Diseases
- Humans
- Japan
- Macular Degeneration
- Neovascularization, Pathologic
Age-related macular degeneration (AMD) affects the macula and is the leading cause of significant and irreversible central visual loss. It is the most common cause of visual loss in people aged more than 60 years. This disease affects 2.5 million individuals in Europe. AMD is caused by both environmental and genetic factors. Numerous risk factors have been reported, but the pathogenesis of AMD is complex and fairly understood. Age, female gender, obesity, race, education status, family history, hyperopia, iris color, cigarette smoking, previous cataract surgery, history of cardiovascular and cerebrovascular disease, diabetes, sunlight exposure and many other factors have been shown to be associated with AMD development. Scientific evidence shows that genes may play a role in the development of nearly 3 out of 4 cases of this devastating eye disease. The genes that have been shown to be associated with AMD are genes encoding complement system components such as CFH, C2, C3, CFB, and other.
MeSH Terms
- Aged
- Aged, 80 and over
- Aging
- Diabetes Complications
- Europe
- Female
- Genetic Predisposition to Disease
- Humans
- Macular Degeneration
- Male
- Middle Aged
- Obesity
- Prevalence
- Risk Factors
Keywords
- Early and late age-related macular degeneration
- Genes
- Risk factors
To investigate the prevalence and genetic characteristics of geographic atrophy (GA) among elderly Japanese with advanced age-related macular degeneration (AMD) in a clinic-based study. Two-hundred and ninety consecutive patients with advanced AMD were classified into typical neovascular AMD, polypoidal choroidal vasculopathy (PCV), retinal angiomatous proliferation (RAP) or geographic atrophy (GA). Genetic variants of ARMS2 A69S (rs10490924) and CFH I62V (rs800292) were genotyped using TaqMan Genotyping Assays. The clinical and genetic characteristics were compared between patients with and without GA. The number of patients diagnosed as having typical neovascular AMD, PCV, RAP and GA were 98 (33.8%), 151 (52.1%), 22 (7.5%) and 19 (6.6%), respectively. Of 19 patients with GA, 13 patients (68.4%) had unilateral GA with exudative AMD in the contralateral eye. Patients with GA were significantly older, with a higher prevalence of reticular pseudodrusen, bilateral involvement of advanced AMD and T-allele frequency of ARMS2 A69S compared with those with typical AMD and PCV; although there were no differences in the genetic and clinical characteristics among patients with GA and RAP. The prevalence of GA was 6.6% among elderly Japanese with AMD. Patients with GA and RAP exhibited genetic and clinical similarities.
MeSH Terms
- Aged
- Aged, 80 and over
- Aging
- Asian Continental Ancestry Group
- Blindness
- Choroid
- Choroidal Neovascularization
- Complement Factor I
- Female
- Gene Frequency
- Geographic Atrophy
- Humans
- Japan
- Male
- Prevalence
- Proteins
- Retrospective Studies
Age-related macular degeneration (AMD) is a common disease that can result in severe visual impairment. Abnormal regulation of the complement system has been implicated in its pathogenesis, and CFH polymorphisms contribute substantially to risk. How these polymorphisms exert their effects is poorly understood. We performed enzyme-linked immunosorbent assay (ELISA) analysis on young, aged, and AMD choroids to determine the abundance of the membrane attack complex (MAC) and performed immunofluorescence studies on eyes from 117 donors to evaluate the MAC in aging, early AMD, and advanced AMD. Morphometric studies were performed on eyes with high- or low-risk CFH genotypes. ELISA confirmed that MAC increases significantly with aging and with AMD. MAC was localized to Bruch's membrane and the choriocapillaris and was detectable at low levels as early as 5 years of age. Hard drusen were labeled with anti-MAC antibody, but large or confluent drusen and basal deposits were generally unlabeled. Labeling of retinal pigment epithelium was observed in some cases of advanced AMD, but not in early disease. Eyes homozygous for the high-risk CFH genotype had thinner choroids than low-risk homozygotes (P < 0.05). These findings suggest that increased complement activation in AMD and in high-risk genotypes can lead to loss of endothelial cells in early AMD. Treatments to protect the choriocapillaris in early AMD are needed.
MeSH Terms
- Adult
- Aged
- Aged, 80 and over
- Aging
- Child, Preschool
- Choroid
- Complement Factor H
- Complement Membrane Attack Complex
- Female
- Humans
- Infant
- Infant, Newborn
- Macular Degeneration
- Male
- Middle Aged
- Retinal Pigment Epithelium
- Young Adult
Heparan sulfate (HS) has been implicated in age-related macular degeneration (AMD), since it is the major binding partner for complement factor H (CFH) in human Bruch's membrane (BrM), and CFH has a central role in inhibiting complement activation on extracellular matrices. The aim was to investigate potential aging changes in HS quantity and composition in human BrM. Postmortem human ocular tissue was obtained from donors without known retinal disease. The HS was purified from BrM and neurosensory retina, and after digestion to disaccharides, fluorescently labeled and analyzed by reverse-phase HPLC. The HS and heparanase-1 were detected by immunohistochemistry in macular tissue sections from young and old donors, and binding of exogenously applied recombinant CCP6-8 region of CFH (402Y and 402H variants) was compared. Disaccharide analysis demonstrated that the mean quantity of HS in BrM was 50% lower (P = 0.006) in old versus young donors (average 82 vs. 32 years). In addition, there was a small, but significant decrease in HS sulfation in old BrM. Immunohistochemistry revealed approximately 50% (P = 0.02) less HS in macular BrM in old versus young donors, whereas heparanase-1 increased by 24% in old macular BrM (P = 0.56). In young donor tissue the AMD-associated 402H CCP6-8 bound relatively poorly to BrM, compared to the 402Y form. In BrM from old donors, this difference was significantly greater (P = 0.019). The quantity of HS decreases substantially with age in human BrM, resulting in fewer binding sites for CFH and especially affecting the ability of the 402H variant of CFH to bind BrM.
MeSH Terms
- Adult
- Age Factors
- Aged
- Aged, 80 and over
- Aging
- Bruch Membrane
- Cadaver
- Chromatography, Reverse-Phase
- Female
- Heparitin Sulfate
- Humans
- Macular Degeneration
- Male
- Middle Aged
- Polysaccharide-Lyases
- Retina
Keywords
- AMD
- Bruch's membrane
- heparan sulfate
Differential cell death is a common feature of aging and age-related disease. In the retina, 30% of rod photoreceptors are lost over life in humans and rodents. However, studies have failed to show age-related cell death in mouse cone photoreceptors, which is surprising because cone physiological function declines with age. Moreover in human, differential loss of short wavelength cone function is an aspect of age-related retinal disease. Here, cones are examined in young (3-month-old) and aged (12-month-old) C57 mice and also in complement factor H knock out mice (CFH-/-) that have been proposed as a murine model of age-related macular degeneration. In vivo imaging showed significant age-related reductions in outer retinal thickness in both groups over this period. Immunostaining for opsins revealed a specific significant decline of >20% for the medium/long (M/L)-wavelength cones but only in the periphery. S cones numbers were not significantly affected by age. This differential cell loss was backed up with quantitative real-time polymerase chain reaction for the 2 opsins, again showing S opsin was unaffected, but that M/L opsin was reduced particularly in CFH-/- mice. These results demonstrate aged cone loss, but surprisingly, in both genotypes, it is only significant in the peripheral ventral retina and focused on the M/L population and not S cones. We speculate that there may be fundamental differences in differential cone loss between human and mouse that may question the validity of mouse models of human outer retinal aging and pathology.
MeSH Terms
- Aging
- Animals
- Disease Models, Animal
- Humans
- Macular Degeneration
- Mice, Inbred C57BL
- Opsins
- Real-Time Polymerase Chain Reaction
- Retina
- Retinal Cone Photoreceptor Cells
- Retinal Rod Photoreceptor Cells
- Species Specificity
Keywords
- Aging
- Cone
- Photoreceptor
Age-related macular degeneration (AMD) is the major cause of legal blindness in the industrialized world. Polymorphisms and recently discovered rare mutations of the Complement Factor H gene have been shown to be strongly associated with AMD. The deletion of CFH-related proteins 1 and 3, proteins that share homologous regions with CFH, is found in protective haplotypes. The following is a critical review of the current state of knowledge of the implication of CFH and CFH-related proteins 1 and 3 in AMD.
MeSH Terms
- Aging
- Blood Proteins
- Complement C3b Inactivator Proteins
- Complement Factor H
- Humans
- Macular Degeneration
Keywords
- Age-related macular degeneration
- Complement Factor H
- Dégénérescence maculaire liée à l’âge
- Facteur complément H
- Haplotypes protecteurs
- Protective haplotypes
Macular degeneration is a common cause of blindness in the elderly. To identify rare coding variants associated with a large increase in risk of age-related macular degeneration (AMD), we sequenced 2,335 cases and 789 controls in 10 candidate loci (57 genes). To increase power, we augmented our control set with ancestry-matched exome-sequenced controls. An analysis of coding variation in 2,268 AMD cases and 2,268 ancestry-matched controls identified 2 large-effect rare variants: previously described p.Arg1210Cys encoded in the CFH gene (case frequency (fcase) = 0.51%; control frequency (fcontrol) = 0.02%; odds ratio (OR) = 23.11) and newly identified p.Lys155Gln encoded in the C3 gene (fcase = 1.06%; fcontrol = 0.39%; OR = 2.68). The variants suggest decreased inhibition of C3 by complement factor H, resulting in increased activation of the alternative complement pathway, as a key component of disease biology.
MeSH Terms
- Aging
- Complement C3
- Complement Factor H
- Complement Pathway, Alternative
- Gene Frequency
- Genetic Variation
- Genotype
- Macular Degeneration
- Polymorphism, Single Nucleotide
To define the role of rare variants in advanced age-related macular degeneration (AMD) risk, we sequenced the exons of 681 genes within all reported AMD loci and related pathways in 2,493 cases and controls. We first tested each gene for increased or decreased burden of rare variants in cases compared to controls. We found that 7.8% of AMD cases compared to 2.3% of controls are carriers of rare missense CFI variants (odds ratio (OR) = 3.6; P = 2 × 10(-8)). There was a predominance of dysfunctional variants in cases compared to controls. We then tested individual variants for association with disease. We observed significant association with rare missense alleles in genes other than CFI. Genotyping in 5,115 independent samples confirmed associations with AMD of an allele in C3 encoding p.Lys155Gln (replication P = 3.5 × 10(-5), OR = 2.8; joint P = 5.2 × 10(-9), OR = 3.8) and an allele in C9 encoding p.Pro167Ser (replication P = 2.4 × 10(-5), OR = 2.2; joint P = 6.5 × 10(-7), OR = 2.2). Finally, we show that the allele of C3 encoding Gln155 results in resistance to proteolytic inactivation by CFH and CFI. These results implicate loss of C3 protein regulation and excessive alternative complement activation in AMD pathogenesis, thus informing both the direction of effect and mechanistic underpinnings of this disorder.
MeSH Terms
- Aging
- Amino Acid Substitution
- Base Sequence
- Complement Activation
- Complement C3
- Complement C9
- Complement Factor I
- Genetic Predisposition to Disease
- Genetic Variation
- Genotype
- Humans
- Macular Degeneration
- Risk
- Sequence Analysis, DNA
Aging is acommon, progressive and irreversible state of multi-cell dysfunction. Immune aging mainly includes the declines of regenerative capacity and lymphoid lineage differentiation potential, the hyporesponsive to infection and vaccination, the hyperresponsive in the context of inflammatory pathology, and the increased risk of autoimmunity. The dysfunction of aged immune system accelerates the occurrence of aging and age-related diseases. The mutation of immunity genes that affect immune responses accelerates or slows aging process and age-related diseases. The frequencies of acquired immunity genes, such as immune protective HLA II DRB1*11 and DRB*16-associated haplotype, are increased in the longevity populations. The increased susceptibility of immune inflammatory response, morbidity and mortality in the elderly is often associated with decreased frequencies of anti-inflammatory factor IL-10 -1082G allele, TNF-β1 haplotype cnd10T/C, cnd25G/G, -988C/C, -800G/A, low proinflammatory fator TNFa level related extended TNF-A genotype -1031C/C, -863C/A, -857C/C, IL-6-174 CC and IFN-γ 874 T allele as well. The innate immunity genes, such as highly expressed anti-inflammatory 896 G KIR4 allele, CCR5Δ32 variant, -765 C Cox-2 allele, -1708 G and 21 C 5-Lox alleles are detected in centenarians. In age-related diseases, a higher CMV-specific IgG antibody level in elderly individuals is associated with a decreased frequency of KIR haplotypes KIR2DS5 and A1B10 and an increased frequency of MBL2 haplotypes LYPB, LYQC and HYPD that result in the absence of MBL2 protein. The increased frequencies of CRP ATG haplotypes and CFH 402 His allele indicate high mortality in the elderly. In the present study, we review the advances in the polymorphism and haplotype of innate and adoptive immunity genes, and their association with both aging and age-related diseases. To strengthen the analysis of extended haplotypes, epigenetic studies of immunity genes and genetic study of hematopoietic stem cell senescence will be helpful to understand the accurate basis of aging-related immune genetics better.
MeSH Terms
- Aged
- Aged, 80 and over
- Aging
- Female
- HLA-DR Antigens
- Humans
- Immunity
- Male
- Middle Aged
- Polymorphism, Genetic
We previously reported that aged mice lacking complement factor H (CFH) exhibit visual defects and structural changes in the retina. However, it is not known whether this phenotype is age-related or is the consequence of disturbed development. To address this question we investigated the effect of Cfh gene deletion on the retinal phenotype of young and mid-age mice. Cfh(-/-) mouse eyes exhibited thickening of the retina and reduced nuclear density, but relatively normal scotopic and photopic electroretinograms. At 12 months there was evidence of subtle astroglial activation in the Cfh(-/-) eyes, and significant elevation of the complement regulator, decay-accelerating factor (DAF) in Müller cells. In the retinal pigment epithelium (RPE) of young control and Cfh(-/-) animals mitochondria and melanosomes were oriented basally and apically respectively, whereas the apical positioning of melanosomes was significantly perturbed in the mid-age Cfh(-/-) RPE. We conclude that deletion of Cfh in the mouse leads to defects in the retina that precede any marked loss of visual function, but which become progressively more marked as the animals age. These observations are consistent with a lifelong role for CFH in retinal homeostasis.
MeSH Terms
- Aging
- Animals
- CD55 Antigens
- Complement Factor H
- Electroretinography
- Evoked Potentials, Visual
- Glial Fibrillary Acidic Protein
- Immunohistochemistry
- Melanosomes
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Microscopy, Electron, Transmission
- Mitochondria
- Photic Stimulation
- Retina
- Retinal Pigment Epithelium
- Visual Acuity
- Visual Pathways