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Dolan K, Liao SM, Crowley M, Xiang C, Adams CM, Brown A, Vo N, Chen A, Delgado O, Buchanan N, Guo C, Prasanna G. Complement Factor B Inhibition or Deletion Is Not Sufficient to Prevent Neurodegeneration in a Murine Model of Glaucoma. J Ocul Pharmacol Ther 2024. [PMID: 38976487 DOI: 10.1089/jop.2024.0046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024] Open
Abstract
Purpose: Activation of the classical complement pathway is thought to contribute to the development and progression of glaucoma. The role of alternative complement or amplification pathways in glaucoma is not well understood. We evaluated complement factor B (FB) expression in postmortem human ocular tissues with or without glaucoma and the effect of FB inhibition and deletion in a mouse ocular hypertensive model of glaucoma induced by photopolymerized hyaluronic acid glycidyl methacrylate (HAGM). Methods: Human CFB mRNA in human eyes was assessed by RNAscope and TaqMan. HAGM model was performed on C57BL6/J mice. The effect of FB in HAGM model was evaluated with an oral FB inhibitor and Cfb-/- mice. Complement mRNA and proteins in mouse eyes were assessed by TaqMan and western blot, respectively. Results: CFB mRNA in human glaucomatous macular neural retina and optic nerve head was upregulated. Cfb mRNA is also upregulated in the HAGM model. Oral FB inhibitor, ED-79-GX17, dosed daily at 200 mg/kg for 3 days after intraocular pressure (IOP) induction in wild-type mice showed complement inhibition in ocular tissues and significantly inhibited systemic complement levels. Daily dosing of ED-79-GX17 for 30 days or Cfb deletion was also unable to prevent retinal ganglion cell or axon loss 30 days after IOP induction in mice. Conclusion: The alternative complement component FB may not substantially contribute to RGC loss in the HAGM mouse glaucoma model despite upregulation of Cfb expression and activation of the alternative pathway. The relevance of these findings to human glaucoma remains to be determined.
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Affiliation(s)
- Katie Dolan
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Sha-Mei Liao
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Maura Crowley
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Chuanxi Xiang
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Christopher M Adams
- Global Discovery Chemistry, Novartis Institutes for Biomedical Research NBR, Cambridge, Massachusetts
| | - Ann Brown
- Discovery/Bioanalytics, Translational Medicine, Novartis Institutes for Biomedical Research NBR, Cambridge, Massachusetts
| | - Nhi Vo
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Amy Chen
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Omar Delgado
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Natasha Buchanan
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Chenying Guo
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
| | - Ganesh Prasanna
- Ophthalmology, Novartis BioMedical Research (NBR), Cambridge, Massachusetts
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2
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Heier JS, Cohen MN, Chao DL, Pepio A, Shiraga Y, Capuano G, Rogers A, Ackert J, Sen HN, Csaky K. Phase 1 Study of JNJ-81201887 Gene Therapy in Geographic Atrophy Secondary to Age-Related Macular Degeneration. Ophthalmology 2024:S0161-6420(24)00368-3. [PMID: 38909914 DOI: 10.1016/j.ophtha.2024.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 06/07/2024] [Accepted: 06/17/2024] [Indexed: 06/25/2024] Open
Abstract
PURPOSE To evaluate the safety and tolerability of a single intravitreal injection of JNJ-81201887 (JNJ-1887) in patients with geographic atrophy (GA) secondary to advanced dry age-related macular degeneration (AMD). DESIGN Phase 1, open-label, single-center, first-in-human clinical study. PARTICIPANTS Adult patients (≥50 years of age) with GA secondary to AMD in the study-treated eye (treated eye) with Snellen best-corrected visual acuity of 20/200 or worse in the treated eye (20/80 or worse after the first 3 patients), a total GA lesion size between 5 and 20 mm2 (2-8 disc area), and best-corrected visual acuity of 20/800 or better in fellow, nontreated eye were included. METHODS Patients (n = 17) were enrolled sequentially into low-dose (3.56 × 1010 viral genome/eye; n = 3), intermediate-dose (1.07 × 1011 viral genome/eye; n = 3), and high-dose (3.56 × 1011 viral genome/eye; n = 11) cohorts without steroid prophylaxis and assessed for safety and tolerability over 24 months. MAIN OUTCOME MEASURES Safety and tolerability outcomes included assessment of ocular and nonocular treatment-emergent adverse events (AEs) over 24 months. Secondary outcomes included GA lesion size and growth rate. RESULTS Baseline patient characteristics were consistent with the disease under study, and all enrolled patients demonstrated foveal center-involved GA. JNJ-81201887 was well-tolerated across all cohorts, with no dose-limiting AEs. No serious or systemic AEs related to study intervention occurred. Overall, 5 of 17 patients (29%) experienced 5 events of mild ocular inflammation related to study treatment; examination findings in all resolved, and AEs resolved in 4 of 5 patients after topical steroids or observation. One unresolved vitritis event, managed with observation, occurred in a patient with an unrelated fatal AE. No endophthalmitis or new-onset choroidal neovascularization was reported. Geographic atrophy lesion growth rate was similar among all cohorts over 24 months. For treated eyes in the high-dose cohort, GA lesion growth rate showed continued decline through 24 months, with a reduction in mean square root lesion growth from 0.211 mm at months 0 through 6 to 0.056 mm at months 18 through 24. CONCLUSIONS All 3 studied doses of JNJ-1887 showed a manageable safety profile through 24 months of follow-up. Further investigation of JNJ-1887 for the treatment of GA is warranted. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
| | - Michael N Cohen
- The Retina Service of Wills Eye Hospital, Mid Atlantic Retina, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Daniel L Chao
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey
| | - Anthony Pepio
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey; Janssen, Inc., Toronto, Ontario, Canada.
| | - Yoko Shiraga
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey
| | - George Capuano
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey
| | - Adam Rogers
- Hemera Biosciences, LLC, Waltham, Massachusetts
| | - Jessica Ackert
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey
| | - H Nida Sen
- Janssen Research & Development, LLC, a Johnson & Johnson Company, Raritan, New Jersey
| | - Karl Csaky
- Retina Foundation of the Southwest, Dallas, Texas
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3
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Seddon JM, De D, Rosner B. Family History of Age-Related Macular Degeneration and Genetics Predict Progression to Advanced Age-Related Macular Degeneration Adjusting for Macular Status, Demographic, and Lifestyle Factors. Am J Ophthalmol 2023; 255:74-86. [PMID: 37437830 DOI: 10.1016/j.ajo.2023.06.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 06/16/2023] [Accepted: 06/16/2023] [Indexed: 07/14/2023]
Abstract
PURPOSE To determine if a family history of age-related macular degeneration (AMD) and genetic variants identify eyes at higher risk for progression to advanced AMD (AAMD), after controlling for baseline demographics, behavioral factors, and macular status. DESIGN Prospective, longitudinal cohort study. METHODS Eyes were classified using the Age-Related Eye Disease Study severity scale. Non-genetic and genetic predictors for progression to AAMD, geographic atrophy, and neovascular disease were evaluated. Cox proportional hazards models using the eye as the unit of analysis were used to calculate hazard ratios (HRs), accounting for correlated data. Discrimination between progressing and non-progressing eyes was assessed using C-statistics and net reclassification improvement (NRI). RESULTS Among 4910 eyes, 863 progressed to AAMD over 12 years. Baseline AMD severity scale and status of the fellow eye were important predictors; genes provided additional discrimination. A family history of AMD also independently predicted progression after accounting for genetic and other covariates: 1 family member versus none (HR 1.21 [95% confidence interval {CI} 1.02-1.43]; P = 0.03); ≥2 family members versus none (HR 1.55 [95% CI 1.26-1.90]; P < 0.001). A composite risk score calculated using β estimates of both non-genetic and significant genetic factors predicted progression to AAMD (HR 5.57; 90th vs 10th percentile; area under the receiver operating characteristic curve [AUC] = 0.92), providing superior fit compared with other models, including one with only ocular variables (NRI = 0.34; P < 0.001; AUC = 0.87, ΔAUC 0.05 ± 0.005; P < 0.001). CONCLUSION Genetic variants and family history provided additional discrimination for predicting progression to AAMD, after accounting for baseline macular status and other covariates.
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Affiliation(s)
- Johanna M Seddon
- From the Department of Ophthalmology and Visual Sciences (J.M.S., D.D.), University of Massachusetts Chan Medical School, Worcester, Massachusetts.
| | - Dikha De
- From the Department of Ophthalmology and Visual Sciences (J.M.S., D.D.), University of Massachusetts Chan Medical School, Worcester, Massachusetts
| | - Bernard Rosner
- Department of Medicine (B.R.), Channing Division of Network Medicine, Harvard Medical School, Boston, Massachusetts, USA
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Rathi S, Hasan R, Ueffing M, Clark SJ. Therapeutic targeting of the complement system in ocular disease. Drug Discov Today 2023; 28:103757. [PMID: 37657753 DOI: 10.1016/j.drudis.2023.103757] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/18/2023] [Accepted: 08/25/2023] [Indexed: 09/03/2023]
Abstract
The complement system is involved in the pathogenesis of several ocular diseases, providing a rationale for the investigation of complement-targeting therapeutics for these conditions. Dry age-related macular degeneration, as characterised by geographic atrophy (GA), is currently the most active area of research for complement-targeting therapeutics, with a complement C3 inhibitor approved in the United States earlier this year marking the first approved therapy for GA. This review discusses the role of complement in ocular disease, provides an overview of the complement-targeting agents currently under development for ocular conditions, and reflects on the lessons that can be learned from the preclinical investigations and clinical trials conducted in this field to date.
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Affiliation(s)
- Sonika Rathi
- Institute for Ophthalmic Research, Department for Ophthalmology, University Medical Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | | | - Marius Ueffing
- Institute for Ophthalmic Research, Department for Ophthalmology, University Medical Center, Eberhard Karls University of Tübingen, Tübingen, Germany.
| | - Simon J Clark
- Institute for Ophthalmic Research, Department for Ophthalmology, University Medical Center, Eberhard Karls University of Tübingen, Tübingen, Germany; University Eye Clinic, University Hospital Tübingen, Tübingen, Germany; Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, UK.
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5
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Molcak H, Jiang K, Campbell CJ, Matsubara JA. Purinergic signaling via P2X receptors and mechanisms of unregulated ATP release in the outer retina and age-related macular degeneration. Front Neurosci 2023; 17:1216489. [PMID: 37496736 PMCID: PMC10366617 DOI: 10.3389/fnins.2023.1216489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/26/2023] [Indexed: 07/28/2023] Open
Abstract
Age-related macular degeneration (AMD) is a chronic and progressive inflammatory disease of the retina characterized by photoceptor loss and significant central visual impairment due to either choroidal neovascularization or geographic atrophy. The pathophysiology of AMD is complex and multifactorial, driven by a combination of modifiable and non-modifiable risk factors, molecular mechanisms, and cellular processes that contribute to overall disease onset, severity, and progression. Unfortunately, due to the structural, cellular, and pathophysiologic complexity, therapeutic discovery is challenging. While purinergic signaling has been investigated for its role in the development and treatment of ocular pathologies including AMD, the potential crosstalk between known contributors to AMD, such as the complement cascade and inflammasome activation, and other biological systems, such as purinergic signaling, have not been fully characterized. In this review, we explore the interactions between purinergic signaling, ATP release, and known contributors to AMD pathogenesis including complement dysregulation and inflammasome activation. We begin by identifying what is known about purinergic receptors in cell populations of the outer retina and potential sources of extracellular ATP required to trigger purinergic receptor activation. Next, we examine evidence in the literature that the purinergic system accelerates AMD pathogenesis leading to apoptotic and pyroptotic cell death in retinal cells. To fully understand the potential role that purinergic signaling plays in AMD, more research is needed surrounding the expression, distribution, functions, and interactions of purinergic receptors within cells of the outer retina as well as potential crosstalk with other systems. By determining how these processes are affected in the context of purinergic signaling, it will improve our understanding of the mechanisms that drive AMD pathogenesis which is critical in developing treatment strategies that prevent or slow progression of the disease.
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Affiliation(s)
- Haydn Molcak
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
| | - Kailun Jiang
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
| | | | - Joanne A. Matsubara
- Matsubara Lab, Faculty of Medicine, Department of Ophthalmology and Visual Sciences, Eye Care Centre, Vancouver, BC, Canada
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Seddon JM, Rosner B, De D, Huan T, Java A, Atkinson J. Rare Dysfunctional Complement Factor I Genetic Variants and Progression to Advanced Age-Related Macular Degeneration. OPHTHALMOLOGY SCIENCE 2023; 3:100265. [PMID: 36909148 PMCID: PMC9993025 DOI: 10.1016/j.xops.2022.100265] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 12/02/2022] [Accepted: 12/27/2022] [Indexed: 12/31/2022]
Abstract
Purpose To evaluate associations between rare dysfunctional complement factor I (CFI) genetic variant status and progression to advanced age-related macular degeneration (AAMD), geographic atrophy (GA), and neovascular disease (NV). Design Prospective, longitudinal study. Participants Patients aged 55 to 80 years at baseline identifying as White with non-AAMD in 1 or both eyes at baseline were included. Follow-up grades were assigned as early, intermediate, or AAMD (GA or NV). CFI variants were categorized using genotyping and sequencing platforms. Methods Analyses were performed using the Seddon Longitudinal Cohort Study (N = 2116 subjects, 3901 eyes, and mean follow-up of 8.3 years) and the Age-Related Eye Disease Study (N = 2837 subjects, 5200 eyes, and mean follow-up of 9.2 years). CFI rare variants associated with low serum factor I (FI) protein levels and decreased FI function (type 1), other AMD genetic variants, and demographic, behavioral, and ocular factors were evaluated. Generalized estimating equations methods were used to assess the association between CFI rare variants and progression, independent of other genetic variants and covariates. Main Outcome Measures Progression to AAMD, GA, or NV. Results In the prospective cohort of 4953 subjects (9101 eyes with non-AAMD at baseline), 1% were type 1 rare CFI carriers. Over 12 years, progression to AAMD was 44% for carriers and 20% for noncarriers (P < 0.001), 30% of carriers versus 10% of noncarriers progressed to GA (P < 0.001), and 18% of carriers compared with 11% of noncarriers progressed to NV (P = 0.049). CFI carriers were more likely to have a family history of AMD (P for trend = 0.035) and a higher baseline AMD grade (P < 0.001). After adjusting for all covariates, CFI carrier status was associated with progression to GA (odds ratio [OR] = 1.91; 95% confidence interval [CI] = 1.03, 3.52) but not NV (OR = 0.96). Higher body mass index was associated with progression among CFI carriers (body mass index ≥ 25 vs. < 25; OR = 5.8; 95% CI 1.5, 22.3) but not for noncarriers (OR = 1.1; 95% CI = 0.9, 1.3), with P_interaction = 0.011. Conclusions Results suggest that carriers of rare dysfunctional type 1 CFI variants are at higher risk for progression to AAMD with GA. Financial Disclosures Proprietary or commercial disclosure may be found after the references.
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Key Words
- AAMD, advanced age-related macular degeneration
- AMD, age-related macular degeneration
- AREDS, Age-Related Eye Disease Study
- Advanced age-related macular degeneration
- BMI, body mass index
- C3, complementcomponent 3
- C9, complementcomponent 9
- CD35, cluster of differentiation 35 (also called complement receptor 1)
- CD46, cluster of differentiation 46 (also called membrane cofactor protein)
- CFH, complementfactor H
- CFI, complement factor I
- CI, confidence interval
- COOH, carboxy terminal
- CR1, complement receptor 1
- Complement factor I
- FI, factor I protein
- GA, geographic atrophy
- GRS, genetic risk score
- Genetic variants
- Geographic atrophy
- HR, hazard ratio
- NH2, amino terminal
- NV, neovascular
- Neovascular disease
- OR, odds ratio
- SAS, Statistical Analysis System
- SLCS, Seddon Longitudinal Cohort Study
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Affiliation(s)
- Johanna M. Seddon
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts
| | - Bernard Rosner
- Channing Division of Network Medicine, Harvard Medical School, Boston, Massachusetts
| | - Dikha De
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts
| | - Tianxiao Huan
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts
| | - Anuja Java
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - John Atkinson
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
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7
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Piri N, Kaplan HJ. Role of Complement in the Onset of Age-Related Macular Degeneration. Biomolecules 2023; 13:biom13050832. [PMID: 37238702 DOI: 10.3390/biom13050832] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 05/09/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
Age-related macular degeneration (AMD) is a progressive degenerative disease of the central retina and the leading cause of severe loss of central vision in people over age 50. Patients gradually lose central visual acuity, compromising their ability to read, write, drive, and recognize faces, all of which greatly impact daily life activities. Quality of life is significantly affected in these patients, and there are worse levels of depression as a result. AMD is a complex, multifactorial disease in which age and genetics, as well as environmental factors, all play a role in its development and progression. The mechanism by which these risk factors interact and converge towards AMD are not fully understood, and therefore, drug discovery is challenging, with no successful therapeutic attempt to prevent the development of this disease. In this review, we describe the pathophysiology of AMD and review the role of complement, which is a major risk factor in the development of AMD.
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Affiliation(s)
- Niloofar Piri
- Department of Ophthalmology, School of Medicine, Saint Louis University, St. Louis, MO 63104, USA
| | - Henry J Kaplan
- Departments of Ophthalmology and Biochemistry & Molecular Biology, School of Medicine, Saint Louis University, St. Louis, MO 63104, USA
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8
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Abstract
Primitive underpinnings of the alternative pathway (AP), namely, a C3-like protein, likely arose more than a billion years ago. The development of an AP amplification loop, while greatly enhancing speed and potency, also presents a double-edged sword. Although critical to combat an infectious disease, it is also potentially destructive, particularly in a chronic disease process involving vital organs where scarring and reduction of regulatory function can occur. Furthermore, new knowledge is pointing to genetic factors involved in an increasing number of complement-related diseases such as age-related macular degeneration. However, even a normal functioning repertoire of complement components can drive cellular damage as a result of low-level complement activation over time. Thus, the modern human AP now faces a new challenge: cumulatively-driven tissue damage from chronic inflammatory processes that mediate cellular injury. The impact of ongoing low-level AP-enhanced complement activation in disease processes is just beginning to be appreciated and studied. However, the sheer numbers of individuals affected by chronic diseases emphasize the need for novel therapeutic agents capable of modulating the AP. The more we learn about this ancient system, the greater is the likelihood of developing fresh perspectives that could contribute to improved human health.
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Affiliation(s)
- M. Kathryn Liszewski
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, 63110, USA
| | - John P. Atkinson
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, 63110, USA
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9
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Schmidt CQ, Smith RJH. Protein therapeutics and their lessons: Expect the unexpected when inhibiting the multi-protein cascade of the complement system. Immunol Rev 2023; 313:376-401. [PMID: 36398537 PMCID: PMC9852015 DOI: 10.1111/imr.13164] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Over a century after the discovery of the complement system, the first complement therapeutic was approved for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). It was a long-acting monoclonal antibody (aka 5G1-1, 5G1.1, h5G1.1, and now known as eculizumab) that targets C5, specifically preventing the generation of C5a, a potent anaphylatoxin, and C5b, the first step in the eventual formation of membrane attack complex. The enormous clinical and financial success of eculizumab across four diseases (PNH, atypical hemolytic uremic syndrome (aHUS), myasthenia gravis (MG), and anti-aquaporin-4 (AQP4) antibody-positive neuromyelitis optica spectrum disorder (NMOSD)) has fueled a surge in complement therapeutics, especially targeting diseases with an underlying complement pathophysiology for which anti-C5 therapy is ineffective. Intensive research has also uncovered challenges that arise from C5 blockade. For example, PNH patients can still face extravascular hemolysis or pharmacodynamic breakthrough of complement suppression during complement-amplifying conditions. These "side" effects of a stoichiometric inhibitor like eculizumab were unexpected and are incompatible with some of our accepted knowledge of the complement cascade. And they are not unique to C5 inhibition. Indeed, "exceptions" to the rules of complement biology abound and have led to unprecedented and surprising insights. In this review, we will describe initial, present and future aspects of protein inhibitors of the complement cascade, highlighting unexpected findings that are redefining some of the mechanistic foundations upon which the complement cascade is organized.
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Affiliation(s)
- Christoph Q. Schmidt
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany
| | - Richard J. H. Smith
- Departments of Internal Medicine and Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
- Molecular Otolaryngology and Renal Research Laboratories, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
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10
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Peters K. Physiology and pathology of the C3 amplification cycle: A retrospective. Immunol Rev 2023; 313:217-224. [PMID: 36408746 PMCID: PMC10099761 DOI: 10.1111/imr.13165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The C3 "Tickover" hypothesis, a mechanism whereby the host maintains constant surveillance of potential invading pathogens, targeting them for elimination through amplified C3b generation and C3-dependent effector mechanisms, was proposed by the late Professor Peter Lachmann in 1973. This unique insight came from a combined understanding of the complement system as it was then defined and the nature of the disease process in rare complement deficiencies and complement-driven diseases. In this review, I give a personal perspective of how understanding of "Tickover" has developed in the subsequent 50 years, culminating in the introduction into the clinic of therapeutic agents designed to combat amplification-driven disease.
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11
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Arslan J, Benke KK. Application of Machine Learning to Ranking Predictors of Anti-VEGF Response. LIFE (BASEL, SWITZERLAND) 2022; 12:life12111926. [PMID: 36431061 PMCID: PMC9699567 DOI: 10.3390/life12111926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/03/2022] [Accepted: 11/08/2022] [Indexed: 11/22/2022]
Abstract
Age-related macular degeneration (AMD) is a heterogeneous disease affecting the macula of individuals and is a cause of irreversible vision loss. Patients with neovascular AMD (nAMD) are candidates for the anti-vascular endothelial growth factor (anti-VEGF) treatment, designed to regress the growth of abnormal blood vessels in the eye. Some patients fail to maintain vision despite treatment. This study aimed to develop a prediction model based on features weighted in order of importance with respect to their impact on visual acuity (VA). Evaluations included an assessment of clinical, lifestyle, and demographic factors from patients that were treated over a period of two years. The methods included mixed-effects and relative importance modelling, and models were tested against model selection criteria, diagnostic and assumption checks, and forecasting errors. The most important predictors of an anti-VEGF response were the baseline VA of the treated eye, the time (in weeks), treatment quantity, and the treated eye. The model also ranked the impact of other variables, such as intra-retinal fluid, haemorrhage, pigment epithelium detachment, treatment drug, baseline VA of the untreated eye, and various lifestyle and demographic factors. The results identified variables that could be targeted for further investigation in support of personalised treatments based on patient data.
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Affiliation(s)
- Janan Arslan
- Sorbonne Université, Institut du Cerveau—Paris Brain Institute—ICM, CNRS, Inria, Inserm, AP-HP, Hôpital de la Pitié Salpêtrière, F-75013 Paris, France
- Centre for Eye Research Australia, Royal Victorian Eye & Ear Hospital, University of Melbourne, East Melbourne, VIC 3002, Australia
- Correspondence: ; Tel.: +33-6-75-22-39-53
| | - Kurt K. Benke
- School of Engineering, University of Melbourne, Parkville, VIC 3010, Australia
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12
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Mallik S, Grodstein F, Bennett DA, Vavvas DG, Lemos B. Novel Epigenetic Clock Biomarkers of Age-Related Macular Degeneration. Front Med (Lausanne) 2022; 9:856853. [PMID: 35783640 PMCID: PMC9244395 DOI: 10.3389/fmed.2022.856853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/19/2022] [Indexed: 01/05/2023] Open
Abstract
Age-Related Macular Degeneration (AMD) is a bilateral ocular condition resulting in irreversible vision impairment caused by the progressive loss of photoreceptors in the macula, a region at the center of the retina. The progressive loss of photoreceptor is a key feature of dry AMD but not always wet AMD, though both forms of AMD can lead to loss of vision. Regression-based biological age clocks are one of the most promising biomarkers of aging but have not yet been used in AMD. Here we conducted analyses to identify regression-based biological age clocks for the retina and explored their use in AMD using transcriptomic data consisting of a total of 453 retina samples including 105 Minnesota Grading System (MGS) level 1 samples, 175 MGS level 2, 112 MGS level 3 and 61 MGS level 4 samples, as well as 167 fibroblast samples. The clocks yielded good separation among AMD samples with increasing severity score viz., MGS1-4, regardless of whether clocks were trained in retina tissue, dermal fibroblasts, or in combined datasets. Clock application to cultured fibroblasts, embryonic stem cells, and induced Pluripotent Stem Cells (iPSCs) were consistent with age reprograming in iPSCs. Moreover, clock application to in vitro neuronal differentiation suggests broader applications. Interesting, many of the age clock genes identified include known targets mechanistically linked to AMD and aging, such as GDF11, C16ORF72, and FBN2. This study provides new observations for retina age clocks and suggests new applications for monitoring in vitro neuronal differentiation. These clocks could provide useful markers for AMD monitoring and possible intervention, as well as potential targets for in vitro screens.
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Affiliation(s)
- Saurav Mallik
- Program in Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA, United States
| | - Fran Grodstein
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - David A. Bennett
- Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, United States
| | - Demetrios G. Vavvas
- Ines and Frederick Yeatts Retina Research Laboratory, Retina Service, Department of Ophthalmology, Mass Eye and Ear, Harvard Medical School, Boston, MA, United States
| | - Bernardo Lemos
- Program in Molecular and Integrative Physiological Sciences, Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, MA, United States
- Broad Institute of Harvard and MIT, Cambridge, MA, United States
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13
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Jones AV, MacGregor S, Han X, Francis J, Harris C, Kavanagh D, Lotery A, Waheed N. Evaluating a Causal Relationship between Complement Factor I Protein Level and Advanced Age-Related Macular Degeneration Using Mendelian Randomization. OPHTHALMOLOGY SCIENCE 2022; 2:100146. [PMID: 35693873 PMCID: PMC9186402 DOI: 10.1016/j.xops.2022.100146] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 01/05/2023]
Abstract
Importance Risk of advanced age-related macular degeneration (AAMD) is associated with rare genetic variants in the gene encoding Complement factor I (CFI), which is associated with lower circulating CFI protein levels, but the nature of the relationship is unclear. Objective Can genetic factors be used to infer whether low circulating CFI is associated with AAMD risk? Design Two-sample inverse variance weighted Mendelian Randomisation (MR) was used to evaluate evidence for a relationship between CFI levels and AAMD risk, comparing CFI levels from genetically predefined subsets in AAMD and control cohorts. Setting Published genetic and proteomic data was combined with data from cohorts of Geographic Atrophy (GA) patients in a series of MR analyses. Participants We derived genetic instruments for systemic CFI level in 3,301 healthy European participants in the INTERVAL study. To evaluate a genetic causal odds ratio (OR) for the effect of CFI levels on AAMD risk, we used results from a genome-wide association study of 12,711 AAMD cases and 14,590 European controls from the International AMD Genomics Consortium (IAMDGC), and CFI levels from patients entered into the research studies SCOPE and SIGHT. Results We identified one common CFI variant rs7439493 which was strongly associated with low CFI level, explaining 4.8% of phenotypic variance. Using rs7439493 our MR analysis estimated that AAMD odds increased per standard deviation (SD) decrease in CFI level; OR 1.47 (95% confidence interval (CI) 1.30-1.65, P=2.1×10-10). We identified one rare variant (rs141853578 encoding p.Gly119Arg) which was genome-wide significantly associated with CFI levels after imputation; based on this, a 1 SD decrease in CFI leads to increased AAMD odds of 1.79 (95% CI 1.46-2.19, P=1.9×10-8). The rare variant rs141853578 explained a further 1.7% of phenotypic variance. To benchmark the effect of low CFI levels on AAMD odds using a CFI-specific proteomic assay, we estimated the effect using CFI levels from 24 rs141853578 positive GA patients; each 1 SD (3.5μg/mL) reduction in CFI was associated with 1.67 fold increased odds of AAMD (95% CI 1.40-2.00, P=1.85×10-8). Conclusion and relevance Excellent concordance in direction and effect size derived from rare and common variant calculations provide good genetic evidence for a potentially causal role of lower CFI level increasing AAMD risk.
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Affiliation(s)
- Amy V. Jones
- Gyroscope Therapeutics Ltd., London, United Kingdom
| | - Stuart MacGregor
- Statistical Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Xikun Han
- Statistical Genetics, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- School of Medicine, University of Queensland, Brisbane, Australia
| | | | - Claire Harris
- Gyroscope Therapeutics Ltd., London, United Kingdom
- Clinical & Translational Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - David Kavanagh
- Clinical & Translational Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
- National Renal Complement Therapeutics Centre, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
| | - Andrew Lotery
- Clinical Neurosciences, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
- Southampton Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom
| | - Nadia Waheed
- Gyroscope Therapeutics Ltd., London, United Kingdom
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts
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14
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Java A, Pozzi N, Schroeder MC, Hu Z, Huan T, Seddon JM, Atkinson J. Functional analysis of rare genetic variants in complement factor I in advanced age-related macular degeneration. Hum Mol Genet 2022; 31:3683-3693. [PMID: 35531992 PMCID: PMC9616575 DOI: 10.1093/hmg/ddac103] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/07/2022] [Accepted: 04/28/2022] [Indexed: 11/14/2022] Open
Abstract
Factor I (FI) is a serine protease inhibitor of the complement system. Heterozygous rare genetic variants in complement factor I (CFI) are associated with advanced age-related macular degeneration (AMD). The clinical impact of these variants is unknown since a majority have not been functionally characterized and are classified as 'variants of uncertain significance' (VUS). This study assessed the functional significance of VUS in CFI. Our previous cross-sectional study using a serum-based assay demonstrated that CFI variants in advanced AMD can be categorized into three types. Type 1 variants cause a quantitative deficiency of FI. Type 2 variants demonstrate a qualitative deficiency. However, Type 3 variants consist of VUS that are less dysfunctional than Types 1 and 2 but are not as biologically active as wild type (WT). In this study, we employed site-directed mutagenesis followed by expression of the recombinant variant and a comprehensive set of functional assays to characterize nine Type 3 variants that were identified in 37 individuals. Our studies establish that the expression of the recombinant protein compared with WT is reduced for R202I, Q217H, S221Y and G263V. Further, G362A and N536K, albeit expressed normally, have significantly less cofactor activity. These results led to re-categorization of CFI variants R202I, Q217H, S221Y and G263V as Type 1 variants and to reclassification of N536K and G362A as Type 2. The variants K441R, Q462H and I492L showed no functional defect and remained as Type 3. This study highlights the utility of an in-depth biochemical analysis in defining the pathologic and clinical implications of complement variants underlying AMD.
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Affiliation(s)
- Anuja Java
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Nicola Pozzi
- Department of Biochemistry and Molecular Biology, Edward A. Doisy Research Center, Saint Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Molly C Schroeder
- Division of Laboratory and Genomic Medicine, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Zheng Hu
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Tianxiao Huan
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Chan Medical School, Worcester, MA 01655, USA
| | | | - John Atkinson
- To whom correspondence should be addressed at: Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA. Tel: +1 3143628391; Fax: +1 3143621366;
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15
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Salminen A, Pietiäinen M, Paju S, Sorsa T, Mäntylä P, Buhlin K, Sinisalo J, Pussinen PJ. Common complement factor H polymorphisms are linked with periodontitis in elderly patients. J Periodontol 2022; 93:1626-1634. [PMID: 35315933 PMCID: PMC10084333 DOI: 10.1002/jper.22-0005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 02/25/2022] [Accepted: 03/04/2022] [Indexed: 11/06/2022]
Abstract
BACKGROUND In our recent genome-wide association study, we found that genetic polymorphisms in the complement factor H (CFH) gene and S100A gene region are strongly associated with serum matrix metalloproteinase 8 (MMP-8) concentration and the release of MMP-8 from neutrophils. As MMP-8 is centrally involved in the pathogenesis of periodontitis, we aimed to evaluate the presence of genetic polymorphisms of S100A8/A9/A12, MMP8, and CFH in periodontitis. In addition, we studied whether polymorphisms of these genes affect the concentrations of S100A8, S100A12, MMP-8, or complement activation marker in saliva. METHODS We genotyped four SNPs (rs1560833 in S100A8/A9/A12, rs11225395 in MMP8, rs800292 in CFH, and rs1061170 in CFH) and measured salivary concentrations of S100A8, S100A12, MMP-8, and terminal complement complex (TCC) in the Parogene cohort (n = 508). The cohort was composed of patients with an indication to coronary angiography and all underwent a clinical and radiographic oral examination. RESULTS Complement factor H polymorphisms rs800292 and rs1061170 were associated with periodontal parameters. None of the polymorphisms showed association with salivary proteins. However, salivary concentrations of S100A8, S100A12, MMP-8, and TCC were strongly associated with the number of periodontal pockets and alveolar bone loss. CONCLUSION Interestingly, genetic variants of CFH, MMP8, and S100A8/A9/A12 gene region did not affect salivary levels of measured proteins. However, saliva levels of S100A8, S100A12, MMP-8, and TCC, and CFH polymorphisms were associated with clinical and radiographic signs of periodontitis. Our study further supports the observations that any dysregulation of complement may increase the risk of inflammatory disorders, such as periodontitis. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Aino Salminen
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Milla Pietiäinen
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Susanna Paju
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Timo Sorsa
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Päivi Mäntylä
- Institute of Dentistry, University of Eastern Finland, Kuopio, Finland.,Oral and Maxillofacial Diseases, Kuopio University Hospital, Kuopio, Finland
| | - Kåre Buhlin
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.,Division of Periodontology, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Juha Sinisalo
- Heart and Lung Center, Helsinki University Hospital, Helsinki, Finland
| | - Pirkko J Pussinen
- Oral and Maxillofacial Diseases, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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16
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Coronado BNL, da Cunha FBS, de Oliveira RM, Nóbrega ODT, Ricart CAO, Fontes W, de Sousa MV, de Ávila MP, Martins AMA. Novel Possible Protein Targets in Neovascular Age-Related Macular Degeneration: A Pilot Study Experiment. Front Med (Lausanne) 2022; 8:692272. [PMID: 35155457 PMCID: PMC8828634 DOI: 10.3389/fmed.2021.692272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 12/14/2021] [Indexed: 11/29/2022] Open
Abstract
Age-related macular degeneration (AMD) is among the world's leading causes of blindness. In its neovascular form (nAMD), around 25% of patients present further anatomical and visual deterioration due to persistence of neovascular activity, despite gold-standard treatment protocols using intravitreal anti-VEGF medications. Thus, to comprehend, the molecular pathways that drive choroidal neoangiogenesis, associated with the vascular endothelial growth factor (VEGF), are important steps to elucidate the mechanistic events underneath the disease development. This is a pilot study, a prospective, translational experiment, in a real-life context aiming to evaluate the protein profiles of the aqueous humor of 15 patients divided into three groups: group 1, composed of patients with nAMD, who demonstrated a good response to anti-VEGF intravitreal injections during follow-up (good responsive); group 2, composed of patients with anti-VEGF-resistant nAMD, who demonstrated choroidal neovascularization activity during follow-up (poor/non-responsive); and group 3, composed of control patients without systemic diseases or signs of retinopathy. For proteomic characterization of the groups, mass spectrometry (label-free LC-MS/MS) was used. A total of 2,336 proteins were identified, of which 185 were distinctly regulated and allowed the differentiation of the clinical conditions analyzed. Among those, 39 proteins, including some novel ones, were analyzed as potential disease effectors through their pathophysiological implications in lipid metabolism, oxidative stress, complement system, inflammatory pathways, and angiogenesis. So, this study suggests the participation of other promising biomarkers in neovascular AMD, in addition to the known VEGF.
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Affiliation(s)
- Bruno Nobre Lins Coronado
- Department of Medical Science, Faculty of Medicine, University of Brasilia, Brasilia, Brazil
- Faculty of Medicine, CESMAC University Center, Maceio, Brazil
- *Correspondence: Bruno Nobre Lins Coronado
| | | | - Raphaela Menezes de Oliveira
- Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | | | - Carlos André Ornelas Ricart
- Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Wagner Fontes
- Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | - Marcelo Valle de Sousa
- Laboratory of Protein Chemistry and Biochemistry, Department of Cell Biology, Institute of Biological Sciences, University of Brasilia, Brasilia, Brazil
| | | | - Aline Maria Araújo Martins
- Department of Medical Science, Faculty of Medicine, University of Brasilia, Brasilia, Brazil
- Department of Health Science, School of Medicine, University Center of Brasilia (UniCEUB), Brasilia, Brazil
- Aline Maria Araújo Martins
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17
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Jones AV, Curtiss D, Harris C, Southerington T, Hautalahti M, Wihuri P, Mäkelä J, Kallionpää RE, Makkonen E, Knopp T, Mannermaa A, Mäkinen E, Moilanen AM, Tezel TH, Waheed NK. An assessment of prevalence of Type 1 CFI rare variants in European AMD, and why lack of broader genetic data hinders development of new treatments and healthcare access. PLoS One 2022; 17:e0272260. [PMID: 36067162 PMCID: PMC9447915 DOI: 10.1371/journal.pone.0272260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 07/14/2022] [Indexed: 11/19/2022] Open
Abstract
PURPOSE Advanced age-related macular degeneration (AAMD) risk is associated with rare complement Factor I (FI) genetic variants associated with low FI protein levels (termed 'Type 1'), but it is unclear how variant prevalences differ between AMD patients from different ethnicities. METHODS Collective prevalence of Type 1 CFI rare variant genotypes were examined in four European AAMD datasets. Collective minor allele frequencies (MAFs) were sourced from the natural history study SCOPE, the UK Biobank, the International AMD Genomics Consortium (IAMDGC), and the Finnish Biobank Cooperative (FINBB), and compared to paired control MAFs or background population prevalence rates from the Genome Aggregation Database (gnomAD). Due to a lack of available genetic data in non-European AAMD, power calculations were undertaken to estimate the AAMD population sizes required to identify statistically significant association between Type 1 CFI rare variants and disease risk in different ethnicities, using gnomAD populations as controls. RESULTS Type 1 CFI rare variants were enriched in all European AAMD cohorts, with odds ratios (ORs) ranging between 3.1 and 7.8, and a greater enrichment was observed in dry AMD from FINBB (OR 8.9, 95% CI 1.49-53.31). The lack of available non-European AAMD datasets prevented us exploring this relationship more globally, however a statistical association may be detectable by future sequencing studies that sample approximately 2,000 AAMD individuals from Ashkenazi Jewish and Latino/Admixed American ethnicities. CONCLUSIONS The relationship between Type 1 CFI rare variants increasing odds of AAMD are well established in Europeans, however the lack of broader genetic data in AAMD has adverse implications for clinical development and future commercialisation strategies of targeted FI therapies in AAMD. These findings emphasise the importance of generating more diverse genetic data in AAMD to improve equity of access to new treatments and address the bias in health care.
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Affiliation(s)
- Amy V. Jones
- Gyroscope Therapeutics Limited, London, United Kingdom
| | - Darin Curtiss
- Gyroscope Therapeutics Limited, London, United Kingdom
| | - Claire Harris
- Gyroscope Therapeutics Limited, London, United Kingdom
| | - Tom Southerington
- Finnish Biobank Cooperative–FINBB, Turku, Finland
- University of Turku, Turku, Finland
| | | | - Pauli Wihuri
- Finnish Biobank Cooperative–FINBB, Turku, Finland
| | | | - Roosa E. Kallionpää
- Auria Biobank, Turku University Hospital and University of Turku, Turku, Finland
| | | | - Theresa Knopp
- Helsinki Biobank, HUS, Helsinki University Hospital, Helsinki, Finland
| | | | - Erna Mäkinen
- Biobank of Central Finland, Hospital Nova of Central Finland, Jyväskylä, Finland
| | - Anne-Mari Moilanen
- Biobank Borealis of Northern Finland, Oulu University Hospital, Oulu, Finland
| | - Tongalp H. Tezel
- Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University College of Physicians and Surgeons, Columbia University Medical Center, New York, NY, United States of America
| | | | - Nadia K. Waheed
- Gyroscope Therapeutics Limited, London, United Kingdom
- Department of Ophthalmology, Tufts University School of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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18
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Kim J, Lee YJ, Won JY. Molecular Mechanisms of Retinal Pigment Epithelium Dysfunction in Age-Related Macular Degeneration. Int J Mol Sci 2021; 22:ijms222212298. [PMID: 34830181 PMCID: PMC8624542 DOI: 10.3390/ijms222212298] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/12/2021] [Accepted: 11/12/2021] [Indexed: 02/06/2023] Open
Abstract
The retinal pigment epithelium (RPE), situated upon Bruch’s membrane, plays multiple roles in the ocular system by interacting with photoreceptors and. Therefore, dysfunction of the RPE causes diseases related to vision loss, such as age-related macular degeneration (AMD). Despite AMD being a global cause of blindness, the pathogenesis remains unclear. Understanding the pathogenesis of AMD is the first step for its prevention and treatment. This review summarizes the common pathways of RPE dysfunction and their effect in AMD. Potential treatment strategies for AMD based on targeting the RPE have also been discussed.
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Affiliation(s)
- Jongmin Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea;
| | - Yeo Jin Lee
- Department of Ophthalmology and Visual Science, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul 03312, Korea;
- Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul 14662, Korea
| | - Jae Yon Won
- Department of Ophthalmology and Visual Science, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul 03312, Korea;
- Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul 14662, Korea
- Correspondence:
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19
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Complement Inhibitors in Age-Related Macular Degeneration: A Potential Therapeutic Option. J Immunol Res 2021; 2021:9945725. [PMID: 34368372 PMCID: PMC8346298 DOI: 10.1155/2021/9945725] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/07/2021] [Accepted: 07/14/2021] [Indexed: 11/18/2022] Open
Abstract
Age-related macular degeneration (AMD) is a multifactorial disease, which can culminate in irreversible vision loss and blindness in elderly. Nowadays, there is a big gap between dry AMD and wet AMD on treatment. Accounting for nearly 90% of AMD, dry AMD still lacks effective treatment. Numerous genetic and molecular researches have confirmed the significant role of the complement system in the pathogenesis of AMD, leading to a deeper exploration of complement inhibitors in the treatment of AMD. To date, at least 14 different complement inhibitors have been or are being explored in AMD in almost 40 clinical trials. While most complement inhibitors fail to treat AMD successfully, two of them are effective in inhibiting the rate of GA progression in phase II clinical trials, and both of them successfully entered phase III trials. Furthermore, recently emerging complement gene therapy and combination therapy also offer new opportunities to treat AMD in the future. In this review, we aim to introduce genetic and molecular associations between the complement system and AMD, provide the updated progress in complement inhibitors in AMD on clinical trials, and discuss the challenges and prospects of complement therapeutic strategies in AMD.
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20
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Choudhury R, Bayatti N, Scharff R, Szula E, Tilakaratna V, Udsen MS, McHarg S, Askari JA, Humphries MJ, Bishop PN, Clark SJ. FHL-1 interacts with human RPE cells through the α5β1 integrin and confers protection against oxidative stress. Sci Rep 2021; 11:14175. [PMID: 34239032 PMCID: PMC8266909 DOI: 10.1038/s41598-021-93708-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 06/16/2021] [Indexed: 12/16/2022] Open
Abstract
Retinal pigment epithelial (RPE) cells that underlie the neurosensory retina are essential for the maintenance of photoreceptor cells and hence vision. Interactions between the RPE and their basement membrane, i.e. the inner layer of Bruch's membrane, are essential for RPE cell health and function, but the signals induced by Bruch's membrane engagement, and their contributions to RPE cell fate determination remain poorly defined. Here, we studied the functional role of the soluble complement regulator and component of Bruch's membrane, Factor H-like protein 1 (FHL-1). Human primary RPE cells adhered to FHL-1 in a manner that was eliminated by either mutagenesis of the integrin-binding RGD motif in FHL-1 or by using competing antibodies directed against the α5 and β1 integrin subunits. These short-term experiments reveal an immediate protein-integrin interaction that were obtained from primary RPE cells and replicated using the hTERT-RPE1 cell line. Separate, longer term experiments utilising RNAseq analysis of hTERT-RPE1 cells bound to FHL-1, showed an increased expression of the heat-shock protein genes HSPA6, CRYAB, HSPA1A and HSPA1B when compared to cells bound to fibronectin (FN) or laminin (LA). Pathway analysis implicated changes in EIF2 signalling, the unfolded protein response, and mineralocorticoid receptor signalling as putative pathways. Subsequent cell survival assays using H2O2 to induce oxidative stress-induced cell death suggest hTERT-RPE1 cells had significantly greater protection when bound to FHL-1 or LA compared to plastic or FN. These data show a non-canonical role of FHL-1 in protecting RPE cells against oxidative stress and identifies a novel interaction that has implications for ocular diseases such as age-related macular degeneration.
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Affiliation(s)
- Rawshan Choudhury
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Nadhim Bayatti
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Richard Scharff
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Ewa Szula
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Viranga Tilakaratna
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Maja Søberg Udsen
- Panum Institute, Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - Selina McHarg
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
| | - Janet A Askari
- Wellcome Centre for Cell-Matrix Research, Division of Cell Matrix Biology & Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Oxford, UK
| | - Martin J Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell Matrix Biology & Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Sciences Centre, University of Manchester, Oxford, UK
| | - Paul N Bishop
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK
- Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, UK
| | - Simon J Clark
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK.
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Oxford, UK.
- Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany.
- University Eye Clinic, Department for Ophthalmology, University of Tübingen, Tübingen, Germany.
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21
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Asahi MG, Avaylon J, Wallsh J, Gallemore RP. Emerging biological therapies for the treatment of age-related macular degeneration. Expert Opin Emerg Drugs 2021; 26:193-207. [PMID: 34030572 DOI: 10.1080/14728214.2021.1931120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Age-related macular degeneration (AMD) is the leading cause of blindness in individuals over age 50 in developed countries. Current therapy for nonexudative AMD (neAMD) is aimed at modifying risk factors and vitamin supplementation to slow progression, while intravitreal anti-vascular endothelial factor (VEGF) injections are the mainstay for treatment of choroidal neovascularization in exudative AMD (eAMD). AREAS COVERED Over the past decade, promising therapies have emerged that aim to improve the current standard of care for both diseases. Clinical trials for neAMD are investigating targets in the complement cascade, vitamin A metabolism, metformin, and tetracycline, whereas clinical trials for eAMD are aiming to decrease treatment burden through novel port delivery systems, increasing drug half-life, and targeting new sites of the VEGF cascade. Stem cell and gene therapy are also being evaluated for treatment of neAMD and eAMD. EXPERT OPINION With an aging population, the need for effective, long term, low burden treatment options for AMD will be in increasingly high demand. Current investigations aim to address the shortcomings of current treatment options with breakthrough treatment approaches. Therapeutics in the pipeline hold promise for improving the treatment of AMD, and are on track for widespread use within the next decade.
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Affiliation(s)
- Masumi G Asahi
- Department of Ophthalmology, George Washington University, Washington, DC, USA
| | - Jaycob Avaylon
- California Northstate University, College of Medicine, Elk Grove, CA, USA
| | - Josh Wallsh
- Department of Ophthalmology, Albany Medical College, Albany, NY, USA
| | - Ron P Gallemore
- Retina Macula Institute, Torrance, CA, USA.,Jules Eye Institute, University of California, Los Angeles, Los Angeles, USA
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22
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Armento A, Ueffing M, Clark SJ. The complement system in age-related macular degeneration. Cell Mol Life Sci 2021; 78:4487-4505. [PMID: 33751148 PMCID: PMC8195907 DOI: 10.1007/s00018-021-03796-9] [Citation(s) in RCA: 110] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 02/05/2021] [Accepted: 02/19/2021] [Indexed: 12/13/2022]
Abstract
Age-related macular degeneration (AMD) is a chronic and progressive degenerative disease of the retina, which culminates in blindness and affects mainly the elderly population. AMD pathogenesis and pathophysiology are incredibly complex due to the structural and cellular complexity of the retina, and the variety of risk factors and molecular mechanisms that contribute to disease onset and progression. AMD is driven by a combination of genetic predisposition, natural ageing changes and lifestyle factors, such as smoking or nutritional intake. The mechanism by which these risk factors interact and converge towards AMD are not fully understood and therefore drug discovery is challenging, where no therapeutic attempt has been fully effective thus far. Genetic and molecular studies have identified the complement system as an important player in AMD. Indeed, many of the genetic risk variants cluster in genes of the alternative pathway of the complement system and complement activation products are elevated in AMD patients. Nevertheless, attempts in treating AMD via complement regulators have not yet been successful, suggesting a level of complexity that could not be predicted only from a genetic point of view. In this review, we will explore the role of complement system in AMD development and in the main molecular and cellular features of AMD, including complement activation itself, inflammation, ECM stability, energy metabolism and oxidative stress.
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Affiliation(s)
- Angela Armento
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Marius Ueffing
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.
| | - Simon J Clark
- Department for Ophthalmology, Institute for Ophthalmic Research, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Department for Ophthalmology, University Eye Clinic, Eberhard Karls University of Tübingen, Tübingen, Germany.
- Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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23
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Yu HJ, Wykoff CC. Investigational Agents in Development for the Treatment of Geographic Atrophy Secondary to Age-Related Macular Degeneration. BioDrugs 2021; 35:303-323. [PMID: 33893984 DOI: 10.1007/s40259-021-00481-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2021] [Indexed: 12/13/2022]
Abstract
Geographic atrophy (GA) is an advanced form of age-related macular degeneration, a late-onset, complex, genetic degenerative disease of the retina. Multiple environmental and genetic factors have been implicated in the development of GA, a pathology ultimately defined by loss of photoreceptors and the underlying retinal pigment epithelium and choriocapillaris. The personal burden of GA has been documented to have a substantial negative impact on quality of life, with progressive and cumulative loss of visual function each year. Currently, there are no treatments to prevent or slow the development or progression of GA. Multiple genetic and histopathologic studies have implicated dysregulation of the complement cascade in GA pathogenesis, leading to the development of several investigational pharmaceuticals targeting key factors in this inflammatory pathway. Several other biochemical pathways have also been implicated in GA development and progression, such as mitochondrial components, mediators of apoptosis and molecules involved in extracellular matrix remodeling, many of which are also being investigated for their potential value as therapeutic targets for GA treatment. Recent advancements in our understanding of GA pathogenesis and the progression of multiple potential therapeutics into later-stage human clinical trials hold great promise for a clinically effective therapeutic for patients with GA to emerge within the near future.
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Affiliation(s)
- Hannah J Yu
- Retina Consultants of Texas, Retina Consultants of America, 4460 Bissonnet St., Suite 200, Bellaire, Texas, 77401, United States
| | - Charles C Wykoff
- Retina Consultants of Texas, Retina Consultants of America, 4460 Bissonnet St., Suite 200, Bellaire, Texas, 77401, United States.
- Blanton Eye Institute, Houston Methodist Hospital, Houston, TX, USA.
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24
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Associations between the Complement System and Choroidal Neovascularization in Wet Age-Related Macular Degeneration. Int J Mol Sci 2020; 21:ijms21249752. [PMID: 33371261 PMCID: PMC7765894 DOI: 10.3390/ijms21249752] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/14/2020] [Accepted: 12/17/2020] [Indexed: 12/16/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness affecting the elderly in the Western world. The most severe form of AMD, wet AMD (wAMD), is characterized by choroidal neovascularization (CNV) and acute vision loss. The current treatment for these patients comprises monthly intravitreal injections of anti-vascular endothelial growth factor (VEGF) antibodies, but this treatment is expensive, uncomfortable for the patient, and only effective in some individuals. AMD is a complex disease that has strong associations with the complement system. All three initiating complement pathways may be relevant in CNV formation, but most evidence indicates a major role for the alternative pathway (AP) and for the terminal complement complex, as well as certain complement peptides generated upon complement activation. Since the complement system is associated with AMD and CNV, a complement inhibitor may be a therapeutic option for patients with wAMD. The aim of this review is to (i) reflect on the possible complement targets in the context of wAMD pathology, (ii) investigate the results of prior clinical trials with complement inhibitors for wAMD patients, and (iii) outline important considerations when developing a future strategy for the treatment of wAMD.
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25
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Meri S, Haapasalo K. Function and Dysfunction of Complement Factor H During Formation of Lipid-Rich Deposits. Front Immunol 2020; 11:611830. [PMID: 33363547 PMCID: PMC7753009 DOI: 10.3389/fimmu.2020.611830] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/09/2020] [Indexed: 01/19/2023] Open
Abstract
Complement-mediated inflammation or dysregulation in lipid metabolism are associated with the pathogenesis of several diseases. These include age-related macular degeneration (AMD), C3 glomerulonephritis (C3GN), dense deposit disease (DDD), atherosclerosis, and Alzheimer's disease (AD). In all these diseases, formation of characteristic lipid-rich deposits is evident. Here, we will discuss molecular mechanisms whereby dysfunction of complement, and especially of its key regulator factor H, could be involved in lipid accumulation and related inflammation. The genetic associations to factor H polymorphisms, the role of factor H in the resolution of inflammation in lipid-rich deposits, modification of macrophage functions, and complement-mediated clearance of apoptotic and damaged cells indicate that the function of factor H is crucial in limiting inflammation in these diseases.
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Affiliation(s)
- Seppo Meri
- Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
- Department of Bacteriology and Immunology, Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Karita Haapasalo
- Department of Bacteriology and Immunology, University of Helsinki, Helsinki, Finland
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26
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Jager MJ, Seddon JM. Eye Diseases Direct Interest to Complement Pathway and Macrophages as Regulators of Inflammation in COVID-19. Asia Pac J Ophthalmol (Phila) 2020; 10:114-120. [PMID: 33290288 DOI: 10.1097/apo.0000000000000346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
ABSTRACT Many of the risk factors for developing severe coronavirus disease 2019 (COVID-19) are also risk factors for eye diseases such as age-related macular degeneration (AMD). During the past decades, macrophages and the complement pathway (as a part of the innate immune system) have been identified as important contributors to the development of AMD, and we suggest that these mechanisms are of similar importance for the clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. Based on the experience with AMD, we discuss how behavioral factors such as diet, smoking and higher body mass index, as well as genetic determinants such as the complement and immune pathway genes may lead to the overactive inflammatory phenotypes seen in some patients with COVID-19, and may in part explain the heterogeneity of disease manifestations and outcomes. Based on this experience, we discuss potential genetic research projects and elaborate on preventive and treatment approaches related to COVID-19.
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Affiliation(s)
| | - Johanna M Seddon
- University of Massachusetts Medical School, Department of Ophthalmology and Visual Sciences, Worcester, MA, USA
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27
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Java A, Baciu P, Widjajahakim R, Sung YJ, Yang J, Kavanagh D, Atkinson J, Seddon J. Functional Analysis of Rare Genetic Variants in Complement Factor I ( CFI) using a Serum-Based Assay in Advanced Age-related Macular Degeneration. Transl Vis Sci Technol 2020; 9:37. [PMID: 32908800 PMCID: PMC7453046 DOI: 10.1167/tvst.9.9.37] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 07/26/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose Factor I (FI) is a serine protease regulator of the complement system. Genetic variants in CFI are associated with advanced age-related macular degeneration (AAMD). However, the clinical and functional impact of these variants is unknown. This study assessed the functional significance of rare CFI variants using a serum-based assay. Methods Carriers of rare variants with (n = 78) and without AAMD (n = 28), and noncarriers with (n = 49) and without AMD (n = 44) were evaluated. Function of FI was determined by measuring the proteolytic cleavage of C3b to iC3b, using the cofactor protein, Factor H. Results CFI variants were categorized into three groups based on antigenic and functional assessments. Type 1 variants (n = 18) in 35 patients with AAMD demonstrated low serum FI levels and a corresponding decrease in FI function. Type 2 variants (n = 6) in 7 individuals demonstrated normal serum FI antigenic levels but reduced degradation of C3b to iC3b. Type 3 variants (n = 15) in 64 individuals demonstrated normal antigenic levels and degradation of C3b to iC3b. However, iC3b generation was low when measured per unit of FI. Thus most rare CFI variants demonstrate either low antigenic levels (type 1) or normal levels but reduced function (types 2 or 3). Conclusions Results provide for the first time a comprehensive functional assessment in serum of CFI rare genetic variants and further establish FI's key role in the pathogenesis of AAMD. Translational Relevance Stratifying patients in the clinic with a rare CFI variant will facilitate screening and targeting patients most likely to benefit from complement therapies.
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Affiliation(s)
- Anuja Java
- Divisions of Nephrology and Rheumatology, Department of Medicine, Washington University, St. Louis, MO, USA
| | | | - Rafael Widjajahakim
- Department of Ophthalmology and Visual Sciences, University of Massachusetts School of Medicine, Worcester, MA, USA
| | - Yun Ju Sung
- Department of Psychiatry and Division of Biostatistics Washington University School of Medicine in St. Louis, MO, USA
| | | | - David Kavanagh
- National Renal Complement Therapeutics Centre, Newcastle University, Newcastle upon Tyne, UK
| | - John Atkinson
- Divisions of Nephrology and Rheumatology, Department of Medicine, Washington University, St. Louis, MO, USA
| | - Johanna Seddon
- Department of Ophthalmology and Visual Sciences, University of Massachusetts School of Medicine, Worcester, MA, USA
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28
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Syed S, Viazmina L, Mager R, Meri S, Haapasalo K. Streptococci and the complement system: interplay during infection, inflammation and autoimmunity. FEBS Lett 2020; 594:2570-2585. [PMID: 32594520 DOI: 10.1002/1873-3468.13872] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 11/09/2022]
Abstract
Streptococci are a broad group of Gram-positive bacteria. This genus includes various human pathogens causing significant morbidity and mortality. Two of the most important human pathogens are Streptococcus pneumoniae (pneumococcus) and Streptococcus pyogenes (group A streptococcus or GAS). Streptococcal pathogens have evolved to express virulence factors that enable them to evade complement-mediated attack. These include factor H-binding M (S. pyogenes) and pneumococcal surface protein C (PspC) (S. pneumoniae) proteins. In addition, S. pyogenes and S. pneumoniae express cytolysins (streptolysin and pneumolysin), which are able to destroy host cells. Sometimes, the interplay between streptococci, the complement, and antistreptococcal immunity may lead to an excessive inflammatory response or autoimmune disease. Understanding the fundamental role of the complement system in microbial clearance and the bacterial escape mechanisms is of paramount importance for understanding microbial virulence, in general, and, the conversion of commensals to pathogens, more specifically. Such insights may help to identify novel antibiotic and vaccine targets in bacterial pathogens to counter their growing resistance to commonly used antibiotics.
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Affiliation(s)
- Shahan Syed
- Department of Bacteriology and Immunology, University of Helsinki, Finland
| | - Larisa Viazmina
- Department of Bacteriology and Immunology, University of Helsinki, Finland
| | | | - Seppo Meri
- Department of Bacteriology and Immunology, University of Helsinki, Finland.,Humanitas University, Milano, Italy
| | - Karita Haapasalo
- Department of Bacteriology and Immunology, University of Helsinki, Finland
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29
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Somasundaran S, Constable IJ, Mellough CB, Carvalho LS. Retinal pigment epithelium and age-related macular degeneration: A review of major disease mechanisms. Clin Exp Ophthalmol 2020; 48:1043-1056. [PMID: 32710488 PMCID: PMC7754492 DOI: 10.1111/ceo.13834] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 07/05/2020] [Accepted: 07/10/2020] [Indexed: 01/18/2023]
Abstract
Age‐related macular degeneration (AMD) is a progressive degenerative disease that is the leading cause of vision loss in the elderly population. Degeneration/dysregulation of the retinal pigment epithelium (RPE), a supportive monolayer of cells underlying the photoreceptors, is commonly seen in patients with AMD. While treatment exists for the neovascular/wet form of AMD, there is currently no cure for the non‐exudative/dry form of AMD, making it imperative to understand the pathogenesis of this disease. Although our understanding of the aetiology of AMD has increased over the years, the underlying disease mechanism has not yet been identified, mainly due to the multifactorial nature of this disease. Herein, we review some of the commonly proposed degeneration pathways of RPE cells and their role in the pathogenesis of AMD; including activation of the complement cascade, oxidative stress‐induced cell death mechanisms, dysfunctional mitochondria and the role of crystallins in AMD disease progression.
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Affiliation(s)
- Shreya Somasundaran
- Centre for Ophthalmology and Visual Science/Lions Eye Institute, University of Western Australia, Nedlands, Western Australia, Australia
| | - Ian J Constable
- Centre for Ophthalmology and Visual Science/Lions Eye Institute, University of Western Australia, Nedlands, Western Australia, Australia
| | - Carla B Mellough
- Centre for Ophthalmology and Visual Science/Lions Eye Institute, University of Western Australia, Nedlands, Western Australia, Australia
| | - Livia S Carvalho
- Centre for Ophthalmology and Visual Science/Lions Eye Institute, University of Western Australia, Nedlands, Western Australia, Australia
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30
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Brodszki N, Frazer-Abel A, Grumach AS, Kirschfink M, Litzman J, Perez E, Seppänen MRJ, Sullivan KE, Jolles S. European Society for Immunodeficiencies (ESID) and European Reference Network on Rare Primary Immunodeficiency, Autoinflammatory and Autoimmune Diseases (ERN RITA) Complement Guideline: Deficiencies, Diagnosis, and Management. J Clin Immunol 2020; 40:576-591. [PMID: 32064578 PMCID: PMC7253377 DOI: 10.1007/s10875-020-00754-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022]
Abstract
This guideline aims to describe the complement system and the functions of the constituent pathways, with particular focus on primary immunodeficiencies (PIDs) and their diagnosis and management. The complement system is a crucial part of the innate immune system, with multiple membrane-bound and soluble components. There are three distinct enzymatic cascade pathways within the complement system, the classical, alternative and lectin pathways, which converge with the cleavage of central C3. Complement deficiencies account for ~5% of PIDs. The clinical consequences of inherited defects in the complement system are protean and include increased susceptibility to infection, autoimmune diseases (e.g., systemic lupus erythematosus), age-related macular degeneration, renal disorders (e.g., atypical hemolytic uremic syndrome) and angioedema. Modern complement analysis allows an in-depth insight into the functional and molecular basis of nearly all complement deficiencies. However, therapeutic options remain relatively limited for the majority of complement deficiencies with the exception of hereditary angioedema and inhibition of an overactivated complement system in regulation defects. Current management strategies for complement disorders associated with infection include education, family testing, vaccinations, antibiotics and emergency planning.
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Affiliation(s)
- Nicholas Brodszki
- Department of Pediatrics, Children's Hospital, Skåne University Hospital, Lund, Sweden
| | - Ashley Frazer-Abel
- Division of Rheumatology, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Anete S Grumach
- Clinical Immunology, Reference Center on Rare Diseases, University Center Health ABC, Santo Andre, SP, Brazil
| | | | - Jiri Litzman
- Department of Clinical Immunology and Allergology, St Anne's University Hospital, and Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Elena Perez
- Allergy Associates of the Palm Beaches, North Palm Beach, FL, USA
| | - Mikko R J Seppänen
- Rare Disease Center, Children's Hospital, and Adult Primary Immunodeficiency Outpatient Clinic, Inflammation Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Kathleen E Sullivan
- Division of Allergy and Immunology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Stephen Jolles
- Immunodeficiency Centre for Wales, Cardiff University & University Hospital of Wales, Cardiff, UK.
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31
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Paraoan L, Sharif U, Carlsson E, Supharattanasitthi W, Mahmud NM, Kamalden TA, Hiscott P, Jackson M, Grierson I. Secretory proteostasis of the retinal pigmented epithelium: Impairment links to age-related macular degeneration. Prog Retin Eye Res 2020; 79:100859. [PMID: 32278708 DOI: 10.1016/j.preteyeres.2020.100859] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 03/24/2020] [Accepted: 03/26/2020] [Indexed: 12/19/2022]
Abstract
Secretory proteostasis integrates protein synthesis, processing, folding and trafficking pathways that are essential for efficient cellular secretion. For the retinal pigment epithelium (RPE), secretory proteostasis is of vital importance for the maintenance of the structural and functional integrity of apical (photoreceptors) and basal (Bruch's membrane/choroidal blood supply) sides of the environment it resides in. This integrity is achieved through functions governed by RPE secreted proteins, which include extracellular matrix modelling/remodelling, angiogenesis and immune response modulation. Impaired RPE secretory proteostasis affects not only the extracellular environment, but leads to intracellular protein aggregation and ER-stress with subsequent cell death. Ample recent evidence implicates dysregulated proteostasis as a key factor in the development of age-related macular degeneration (AMD), the leading cause of blindness in the developed world, and research aiming to characterise the roles of various proteins implicated in AMD-associated dysregulated proteostasis unveiled unexpected facets of the mechanisms involved in degenerative pathogenesis. This review analyses cellular processes unveiled by the study of the top 200 transcripts most abundantly expressed by the RPE/choroid in the light of the specialised secretory nature of the RPE. Functional roles of these proteins and the mechanisms of their impaired secretion, due to age and genetic-related causes, are analysed in relation to AMD development. Understanding the importance of RPE secretory proteostasis in relation to maintaining retinal health and how it becomes impaired in disease is of paramount importance for the development and assessment of future therapeutic advancements involving gene and cell therapies.
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Affiliation(s)
- Luminita Paraoan
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom.
| | - Umar Sharif
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Emil Carlsson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Wasu Supharattanasitthi
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom; Department of Physiology, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand
| | - Nur Musfirah Mahmud
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Tengku Ain Kamalden
- Eye Research Centre, Department of Ophthalmology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Paul Hiscott
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Malcolm Jackson
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
| | - Ian Grierson
- Department of Eye and Vision Science, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, United Kingdom
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32
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Hughes S, Gumas J, Lee R, Rumano M, Berger N, Gautam AK, Sfyroera G, Chan AL, Gnanaguru G, Connor KM, Kim BJ, Dunaief JL, Ricklin D, Hajishengallis G, Yancopoulou D, Reis ES, Mastellos DC, Lambris JD. Prolonged intraocular residence and retinal tissue distribution of a fourth-generation compstatin-based C3 inhibitor in non-human primates. Clin Immunol 2020; 214:108391. [PMID: 32229292 DOI: 10.1016/j.clim.2020.108391] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 01/12/2023]
Abstract
Age-related macular degeneration (AMD) is a leading cause of irreversible vision loss among the elderly population. Genetic studies in susceptible individuals have linked this ocular disease to deregulated complement activity that culminates in increased C3 turnover, retinal inflammation and photoreceptor loss. Therapeutic targeting of C3 has therefore emerged as a promising strategy for broadly intercepting the detrimental proinflammatory consequences of complement activation in the retinal tissue. In this regard, a PEGylated second-generation derivative of the compstatin family of C3-targeted inhibitors is currently in late-stage clinical development as a treatment option for geographic atrophy, an advanced form of AMD which lacks approved therapy. While efficacy has been strongly suggested in phase 2 clinical trials, crucial aspects still remain to be defined with regard to the ocular bioavailability, tissue distribution and residence, and dosing frequency of such inhibitors in AMD patients. Here we report the intraocular distribution and pharmacokinetic profile of the fourth-generation compstatin analog, Cp40-KKK in cynomolgus monkeys following a single intravitreal injection. Using a sensitive surface plasmon resonance (SPR)-based competition assay and ELISA, we have quantified both the amount of inhibitor and the concentration of C3 retained in the vitreous of Cp40-KKK-injected animals. Cp40-KKK displays prolonged intraocular residence, being detected at C3-saturating levels for over 3 months after a single intravitreal injection. Moreover, we have probed the distribution of Cp40-KKK within the ocular tissue by means of immunohistochemistry and highly specific anti-Cp40-KKK antibodies. Both C3 and Cp40-KKK were detected in the retinal tissue of inhibitor-injected animals, with prominent co-localization in the choroid one-month post intravitreal injection. These results attest to the high retinal tissue penetrance and target-driven distribution of Cp40-KKK. Given its subnanomolar binding affinity and prolonged ocular residence, Cp40-KKK constitutes a promising drug candidate for ocular pathologies underpinned by deregulated C3 activation.
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Affiliation(s)
- Sarah Hughes
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Justin Gumas
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Rebecca Lee
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Merita Rumano
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Nadja Berger
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Avneesh Kumar Gautam
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Georgia Sfyroera
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Gopalan Gnanaguru
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, MA, USA; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Kip M Connor
- Angiogenesis Laboratory, Department of Ophthalmology, Massachusetts Eye & Ear Infirmary, Boston, MA, USA; Department of Ophthalmology, Harvard Medical School, Boston, MA, United States
| | - Benjamin J Kim
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Joshua L Dunaief
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel Ricklin
- Department of Pharmaceutical Sciences, University of Basel, Switzerland
| | - George Hajishengallis
- Department of Basic and Translational Sciences, Penn Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Edimara S Reis
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | | | - John D Lambris
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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33
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Thurman JM. Complement and the Kidney: An Overview. Adv Chronic Kidney Dis 2020; 27:86-94. [PMID: 32553250 DOI: 10.1053/j.ackd.2019.10.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/10/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022]
Abstract
The complement cascade was first recognized as a downstream effector system of antibody-mediated cytotoxicity. Consistent with this view, it was discovered in the 1960s that complement is activated in the glomeruli of patients with immune complex glomerulonephritis. More recently, research has shown that complement system has many additional functions relating to regulation of the immune response, homeostasis, and metabolism. It has also become clear that the complement system is important to the pathogenesis of many non-immune complex mediated kidney diseases. In fact, in atypical hemolytic uremic syndrome and C3 glomerulopathy, uncontrolled complement activation is the primary driver of disease. Complement activation generates multiple pro-inflammatory fragments, and if not properly controlled it can cause fulminant tissue injury. Furthermore, the mechanisms of complement activation and complement-mediated injury vary from disease to disease. Many new drugs that target the complement cascade are in clinical development, so it is important to fully understand the biology of the complement system and its role in disease.
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34
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Mainolfi N, Ehara T, Karki RG, Anderson K, Mac Sweeney A, Liao SM, Argikar UA, Jendza K, Zhang C, Powers J, Klosowski DW, Crowley M, Kawanami T, Ding J, April M, Forster C, Serrano-Wu M, Capparelli M, Ramqaj R, Solovay C, Cumin F, Smith TM, Ferrara L, Lee W, Long D, Prentiss M, De Erkenez A, Yang L, Liu F, Sellner H, Sirockin F, Valeur E, Erbel P, Ostermeier D, Ramage P, Gerhartz B, Schubart A, Flohr S, Gradoux N, Feifel R, Vogg B, Wiesmann C, Maibaum J, Eder J, Sedrani R, Harrison RA, Mogi M, Jaffee BD, Adams CM. Discovery of 4-((2 S,4 S)-4-Ethoxy-1-((5-methoxy-7-methyl-1 H-indol-4-yl)methyl)piperidin-2-yl)benzoic Acid (LNP023), a Factor B Inhibitor Specifically Designed To Be Applicable to Treating a Diverse Array of Complement Mediated Diseases. J Med Chem 2020; 63:5697-5722. [PMID: 32073845 DOI: 10.1021/acs.jmedchem.9b01870] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The alternative pathway (AP) of the complement system is a key contributor to the pathogenesis of several human diseases including age-related macular degeneration, paroxysmal nocturnal hemoglobinuria (PNH), atypical hemolytic uremic syndrome (aHUS), and various glomerular diseases. The serine protease factor B (FB) is a key node in the AP and is integral to the formation of C3 and C5 convertase. Despite the prominent role of FB in the AP, selective orally bioavailable inhibitors, beyond our own efforts, have not been reported previously. Herein we describe in more detail our efforts to identify FB inhibitors by high-throughput screening (HTS) and leveraging insights from several X-ray cocrystal structures during optimization efforts. This work culminated in the discovery of LNP023 (41), which is currently being evaluated clinically in several diverse AP mediated indications.
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Affiliation(s)
- Nello Mainolfi
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Takeru Ehara
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Rajeshri G Karki
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Karen Anderson
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Aengus Mac Sweeney
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Sha-Mei Liao
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Upendra A Argikar
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Keith Jendza
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Chun Zhang
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - James Powers
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Daniel W Klosowski
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Maura Crowley
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Toshio Kawanami
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Jian Ding
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Myriam April
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Cornelia Forster
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Michael Serrano-Wu
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Michael Capparelli
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Rrezarta Ramqaj
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Catherine Solovay
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Frederic Cumin
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Thomas M Smith
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Luciana Ferrara
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Wendy Lee
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Debby Long
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Melissa Prentiss
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Andrea De Erkenez
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Louis Yang
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Fang Liu
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Holger Sellner
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Finton Sirockin
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Eric Valeur
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Paulus Erbel
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Daniela Ostermeier
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Paul Ramage
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Bernd Gerhartz
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Anna Schubart
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Stefanie Flohr
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Nathalie Gradoux
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Roland Feifel
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Barbara Vogg
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Christian Wiesmann
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Jürgen Maibaum
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Jörg Eder
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Richard Sedrani
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Richard A Harrison
- Novartis Institutes for BioMedical Research, Novartis Pharma AG, CH-4056 Basel, Switzerland
| | - Muneto Mogi
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Bruce D Jaffee
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Christopher M Adams
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
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Cipriani V, Lorés-Motta L, He F, Fathalla D, Tilakaratna V, McHarg S, Bayatti N, Acar İE, Hoyng CB, Fauser S, Moore AT, Yates JRW, de Jong EK, Morgan BP, den Hollander AI, Bishop PN, Clark SJ. Increased circulating levels of Factor H-Related Protein 4 are strongly associated with age-related macular degeneration. Nat Commun 2020; 11:778. [PMID: 32034129 PMCID: PMC7005798 DOI: 10.1038/s41467-020-14499-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 01/10/2020] [Indexed: 12/21/2022] Open
Abstract
Age-related macular degeneration (AMD) is a leading cause of blindness. Genetic variants at the chromosome 1q31.3 encompassing the complement factor H (CFH, FH) and CFH related genes (CFHR1-5) are major determinants of AMD susceptibility, but their molecular consequences remain unclear. Here we demonstrate that FHR-4 plays a prominent role in AMD pathogenesis. We show that systemic FHR-4 levels are elevated in AMD (P-value = 7.1 × 10-6), whereas no difference is seen for FH. Furthermore, FHR-4 accumulates in the choriocapillaris, Bruch's membrane and drusen, and can compete with FH/FHL-1 for C3b binding, preventing FI-mediated C3b cleavage. Critically, the protective allele of the strongest AMD-associated CFH locus variant rs10922109 has the highest association with reduced FHR-4 levels (P-value = 2.2 × 10-56), independently of the AMD-protective CFHR1-3 deletion, and even in those individuals that carry the high-risk allele of rs1061170 (Y402H). Our findings identify FHR-4 as a key molecular player contributing to complement dysregulation in AMD.
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Affiliation(s)
- Valentina Cipriani
- William Harvey Research Institute, Clinical Pharmacology, Queen Mary University of London, London, EC1M 6BQ, UK.
- UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK.
- UCL Genetics Institute, University College London, London, WC1E 6BT, UK.
| | - Laura Lorés-Motta
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Fan He
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Dina Fathalla
- Systems Immunity URI, Division of Infection and Immunity, and UK DRI Cardiff, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
| | - Viranga Tilakaratna
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Selina McHarg
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Nadhim Bayatti
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - İlhan E Acar
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Carel B Hoyng
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - Sascha Fauser
- Department of Ophthalmology, University Hospital of Cologne, Cologne, 50924, Germany
- Roche Pharma Research and Early Development, F. Hoffmann-La Roche Ltd, Basel, 4070, Switzerland
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
- Ophthalmology Department, University of California San Francisco, San Francisco, CA, USA
| | - John R W Yates
- UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, EC1V 2PD, UK
- Department of Medical Genetics, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Eiko K de Jong
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
| | - B Paul Morgan
- Systems Immunity URI, Division of Infection and Immunity, and UK DRI Cardiff, School of Medicine, Cardiff University, Cardiff, CF14 4XN, UK
| | - Anneke I den Hollander
- Department of Ophthalmology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, 6525 GA, The Netherlands
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, 6525 HR, The Netherlands
| | - Paul N Bishop
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK
- Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, M13 9WL, UK
| | - Simon J Clark
- Division of Evolution and Genomic Sciences, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
- The Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
- Department of Ophthalmology, Research Institute of Ophthalmology, Eberhard Karls University of Tübingen, 72076, Tübingen, Germany.
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Haapasalo K, Meri S. Regulation of the Complement System by Pentraxins. Front Immunol 2019; 10:1750. [PMID: 31428091 PMCID: PMC6688104 DOI: 10.3389/fimmu.2019.01750] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 07/10/2019] [Indexed: 01/09/2023] Open
Abstract
The functions of pentraxins, like C-reactive protein (CRP), serum amyloid protein P (SAP) and pentraxin-3 (PTX3), are to coordinate spatially and temporally targeted clearance of injured tissue components, to protect against infections and to regulate related inflammation together with the complement system. For this, pentraxins have a dual relationship with the complement system. Initially, after a focused binding to their targets, e.g., exposed phospholipids or cholesterol in the injured tissue area, or microbial components, the pentraxins activate complement by binding its first component C1q. However, the emerging inflammation needs to be limited to the target area. Therefore, pentraxins inhibit complement at the C3b stage to prevent excessive damage. The complement inhibitory functions of pentraxins are based on their ability to interact with complement inhibitors C4bp or factor H (FH). C4bp binds to SAP, while FH binds to both CRP and PTX3. FH promotes opsonophagocytosis through inactivation of C3b to iC3b, and inhibits AP activity thus preventing formation of the C5a anaphylatoxin and the complement membrane attack complex (MAC). Monitoring CRP levels gives important clinical information about the extent of tissue damage and severity of infections. CRP is a valuable marker for distinguishing bacterial infections from viral infections. Disturbances in the functions and interactions of pentraxins and complement are also involved in a number of human diseases. This review will summarize what is currently known about the FH family proteins and pentraxins that interact with FH. Furthermore, we will discuss diseases, where interactions between these molecules may play a role.
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Affiliation(s)
- Karita Haapasalo
- Department of Bacteriology and Immunology and Translational Immunology Research Program, University of Helsinki, Helsinki, Finland
| | - Seppo Meri
- Department of Bacteriology and Immunology and Translational Immunology Research Program, University of Helsinki, Helsinki, Finland.,HUSLAB, Helsinki University Hospital, Helsinki, Finland.,Department of Biomedical Sciences, Humanitas University, Milan, Italy
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37
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Clinical promise of next-generation complement therapeutics. Nat Rev Drug Discov 2019; 18:707-729. [PMID: 31324874 DOI: 10.1038/s41573-019-0031-6] [Citation(s) in RCA: 209] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2019] [Indexed: 02/07/2023]
Abstract
The complement system plays a key role in pathogen immunosurveillance and tissue homeostasis. However, subversion of its tight regulatory control can fuel a vicious cycle of inflammatory damage that exacerbates pathology. The clinical merit of targeting the complement system has been established for rare clinical disorders such as paroxysmal nocturnal haemoglobinuria and atypical haemolytic uraemic syndrome. Evidence from preclinical studies and human genome-wide analyses, supported by new molecular and structural insights, has revealed new pathomechanisms and unmet clinical needs that have thrust a new generation of complement inhibitors into clinical development for a variety of indications. This review critically discusses recent clinical milestones in complement drug discovery, providing an updated translational perspective that may guide optimal target selection and disease-tailored complement intervention.
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Karki RG, Powers J, Mainolfi N, Anderson K, Belanger DB, Liu D, Ji N, Jendza K, Gelin CF, Mac Sweeney A, Solovay C, Delgado O, Crowley M, Liao SM, Argikar UA, Flohr S, La Bonte LR, Lorthiois EL, Vulpetti A, Brown A, Long D, Prentiss M, Gradoux N, de Erkenez A, Cumin F, Adams C, Jaffee B, Mogi M. Design, Synthesis, and Preclinical Characterization of Selective Factor D Inhibitors Targeting the Alternative Complement Pathway. J Med Chem 2019; 62:4656-4668. [PMID: 30995036 DOI: 10.1021/acs.jmedchem.9b00271] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Complement factor D (FD), a highly specific S1 serine protease, plays a central role in the amplification of the alternative complement pathway (AP) of the innate immune system. Dysregulation of AP activity predisposes individuals to diverse disorders such as age-related macular degeneration, atypical hemolytic uremic syndrome, membranoproliferative glomerulonephritis type II, and paroxysmal nocturnal hemoglobinuria. Previously, we have reported the screening efforts and identification of reversible benzylamine-based FD inhibitors (1 and 2) binding to the open active conformation of FD. In continuation of our drug discovery program, we designed compounds applying structure-based approaches to improve interactions with FD and gain selectivity against S1 serine proteases. We report herein the design, synthesis, and medicinal chemistry optimization of the benzylamine series culminating in the discovery of 12, an orally bioavailable and selective FD inhibitor. 12 demonstrated systemic suppression of AP activation in a lipopolysaccharide-induced AP activation model as well as local ocular suppression in intravitreal injection-induced AP activation model in mice expressing human FD.
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Affiliation(s)
- Rajeshri G Karki
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - James Powers
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Nello Mainolfi
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Karen Anderson
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - David B Belanger
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Donglei Liu
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Nan Ji
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Keith Jendza
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Christine F Gelin
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Aengus Mac Sweeney
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Catherine Solovay
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Omar Delgado
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Maura Crowley
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Sha-Mei Liao
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Upendra A Argikar
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Stefanie Flohr
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Laura R La Bonte
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Edwige L Lorthiois
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Anna Vulpetti
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Ann Brown
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Debby Long
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Melissa Prentiss
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Nathalie Gradoux
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Andrea de Erkenez
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Frederic Cumin
- Novartis Institutes for BioMedical Research , Novartis Campus , CH-4056 Basel , Switzerland
| | - Christopher Adams
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Bruce Jaffee
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
| | - Muneto Mogi
- Novartis Institutes for BioMedical Research , Cambridge , Massachusetts 02139 , United States
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Abstract
Complement is a key component of the innate immune system; however, its dysregulation due to genetic mutations or the presence of autoantibodies can cause a number of diseases including age-related macular degeneration, paroxysmal nocturnal hemoglobinuria, and C3 glomerulopathy. The alternative pathway acts as an amplification loop of the complement system. It is triggered by the activation of factor B, the proteolytically active component of the C3 and C5 convertases. We report the discovery of a small-molecule inhibitor of factor B and demonstrate that it can efficiently block the alternative pathway in vivo in animals and ex vivo in patient samples. The compound is highly selective and potent and is currently in clinical development for a number of complement-mediated diseases. Dysregulation of the alternative complement pathway (AP) predisposes individuals to a number of diseases including paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, and C3 glomerulopathy. Moreover, glomerular Ig deposits can lead to complement-driven nephropathies. Here we describe the discovery of a highly potent, reversible, and selective small-molecule inhibitor of factor B, a serine protease that drives the central amplification loop of the AP. Oral administration of the inhibitor prevents KRN-induced arthritis in mice and is effective upon prophylactic and therapeutic dosing in an experimental model of membranous nephropathy in rats. In addition, inhibition of factor B prevents complement activation in sera from C3 glomerulopathy patients and the hemolysis of human PNH erythrocytes. These data demonstrate the potential therapeutic value of using a factor B inhibitor for systemic treatment of complement-mediated diseases and provide a basis for its clinical development.
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40
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Taylor RL, Poulter JA, Downes SM, McKibbin M, Khan KN, Inglehearn CF, Webster AR, Hardcastle AJ, Michaelides M, Bishop PN, Clark SJ, Black GC. Loss-of-Function Mutations in the CFH Gene Affecting Alternatively Encoded Factor H-like 1 Protein Cause Dominant Early-Onset Macular Drusen. Ophthalmology 2019; 126:1410-1421. [PMID: 30905644 PMCID: PMC6856713 DOI: 10.1016/j.ophtha.2019.03.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/25/2019] [Accepted: 03/11/2019] [Indexed: 02/08/2023] Open
Abstract
Purpose To characterize the molecular mechanism underpinning early-onset macular drusen (EOMD), a phenotypically severe subtype of age-related macular degeneration (AMD), in a subgroup of patients. Design Multicenter case series, in vitro experimentation, and retrospective analysis of previously reported variants. Participants Seven families with apparently autosomal dominant EOMD. Methods Patients underwent a comprehensive ophthalmic assessment. Affected individuals from families A, B, and E underwent whole exome sequencing. The probands from families C, D, F, and G underwent Sanger sequencing analysis of the complement factor H (CFH) gene. Mutant recombinant factor H like-1 (FHL-1) proteins were expressed in HEK293 cells to assess the impact on FHL-1 expression and function. Previously reported EOMD-causing variants in CFH were reviewed. Main Outcome Measures Detailed clinical phenotypes, genomic findings, in vitro characterization of mutation effect on protein function, and postulation of the pathomechanism underpinning EOMD. Results All affected participants demonstrated bilateral drusen. The earliest reported age of onset was 16 years (median, 46 years). Ultra-rare (minor allele frequency [MAF], ≤0.0001) CFH variants were identified as the cause of disease in each family: CFH c.1243del, p.(Ala415ProfsTer39) het; c.350+1G→T het; c.619+1G→A het, c.380G→A, p.(Arg127His) het; c.694C→T p.(Arg232Ter) het (identified in 2 unrelated families in this cohort); and c.1291T→A, p.(Cys431Ser). All mutations affect complement control protein domains 2 through 7, and thus are predicted to impact both FHL-1, the predominant isoform in Bruch’s membrane (BrM) of the macula, and factor H (FH). In vitro analysis of recombinant proteins FHL-1R127H, FHL-1A415f/s, and FHL-1C431S demonstrated that they are not secreted, and thus are loss-of-function proteins. Review of 29 previously reported EOMD-causing mutations found that 75.8% (22/29) impact FHL-1 and FH. In total, 86.2% (25/29) of EOMD-associated variants cause haploinsufficiency of FH or FHL-1. Conclusions Early-onset macular drusen is an underrecognized, phenotypically severe subtype of AMD. We propose that haploinsufficiency of FHL-1, the main regulator of the complement pathway in BrM, where drusen develop, is an important mechanism underpinning the development of EOMD in a number of cases. Understanding the molecular basis of EOMD will shed light on AMD pathogenesis given their pathologic similarities.
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Affiliation(s)
- Rachel L Taylor
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom; Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester, United Kingdom
| | - James A Poulter
- Section of Ophthalmology and Neuroscience, Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Susan M Downes
- Oxford Eye Hospital, Oxford University Hospitals, NHS Foundation Trust, Oxford, United Kingdom; Nuffield Department of Clinical Neuroscience, John Radcliffe Hospital, Oxford, United Kingdom
| | - Martin McKibbin
- Department of Ophthalmology, St. James's University Hospital, Leeds, United Kingdom
| | - Kamron N Khan
- Section of Ophthalmology and Neuroscience, Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Chris F Inglehearn
- Section of Ophthalmology and Neuroscience, Leeds Institute of Medical Research, University of Leeds, Leeds, United Kingdom
| | - Andrew R Webster
- UCL Institute of Ophthalmology, University College London, London, United Kingdom; Moorfields Eye Hospital, London, United Kingdom
| | - Alison J Hardcastle
- UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom; Moorfields Eye Hospital, London, United Kingdom
| | - Paul N Bishop
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom; Manchester Royal Eye Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Simon J Clark
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom; The Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Graeme C Black
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom; Manchester Centre for Genomic Medicine, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, St. Mary's Hospital, Manchester, United Kingdom.
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Prokopiou E, Kolovos P, Kalogerou M, Neokleous A, Nicolaou O, Sokratous K, Kyriacou K, Georgiou T. Omega-3 Fatty Acids Supplementation: Therapeutic Potential in a Mouse Model of Stargardt Disease. Invest Ophthalmol Vis Sci 2019; 59:2757-2767. [PMID: 29860462 DOI: 10.1167/iovs.17-23523] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To evaluate the therapeutic effects of omega-3 (ω3) fatty acids on retinal degeneration in the ABCA4-/- model of Stargardt disease when the blood level of arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratio is between 1 and 1.5. Methods Eight-month-old mice were allocated to three groups: wild type (129S1), ABCA4-/- untreated, and ABCA4-/- ω3 treated. ω3 treatment lasted 3 months and comprised daily gavage administration of EPA and docosahexaenoic acid (DHA). Blood and retinal fatty acid analysis was performed using gas chromatography to adjust the blood AA/EPA ∼1 to 1.5. Eyecups were histologically examined using transmission electron microscopy and confocal microscopy to evaluate lipofuscin granules and the photoreceptor layer. Retinal N-retinylidene-N-retinylethanolamine (A2E), a major component of retinal pigment epithelium lipofuscin, was quantified using liquid chromatography and tandem mass spectrometry, in addition to retinal proteomic analysis to determine changes in inflammatory proteins. Results EPA levels increased and AA levels decreased in the blood and retinas of the treatment group. Significantly less A2E and lipofuscin granules were observed in the treatment group. The thickness of the outer nuclear layer was significantly greater in the treatment group (75.66 ± 4.80 μm) than in the wild-type (61.40 ± 1.84 μm) or untreated ABCA4-/- (56.50 ± 3.24 μm) groups. Proteomic analysis indicated lower levels of complement component 3 (C3) in the treatment group, indicative of lower complement-induced inflammatory response. Conclusions Three months of ω3 supplementation (AA/EPA ∼1-1.5) reduces A2E levels, lipofuscin granules, and C3 levels in the ABCA4-/- mouse model of Stargardt disease, consistent with slowing of the disease.
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Affiliation(s)
| | | | - Maria Kalogerou
- Ophthalmos Research and Educational Institute, Nicosia, Cyprus
| | | | - Orthodoxia Nicolaou
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, The Cyprus School of Molecular Medicine, Nicosia, Cyprus
| | - Kleitos Sokratous
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, The Cyprus School of Molecular Medicine, Nicosia, Cyprus.,Bioinformatics Group, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Kyriacos Kyriacou
- Department of Electron Microscopy and Molecular Pathology, The Cyprus Institute of Neurology and Genetics, The Cyprus School of Molecular Medicine, Nicosia, Cyprus
| | - Tassos Georgiou
- Ophthalmos Research and Educational Institute, Nicosia, Cyprus
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Seddon JM, Rosner B. Validated Prediction Models for Macular Degeneration Progression and Predictors of Visual Acuity Loss Identify High-Risk Individuals. Am J Ophthalmol 2019; 198:223-261. [PMID: 30389371 DOI: 10.1016/j.ajo.2018.10.022] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 10/15/2018] [Accepted: 10/19/2018] [Indexed: 01/08/2023]
Abstract
PURPOSE To determine predictive factors and risk scores for conversion to overall advanced age-related macular degeneration (AMD), geographic atrophy (GA), neovascular disease (NV), and loss of vision, and to validate the model for AMD in an external cohort. METHODS Progression to advanced AMD was evaluated using stepwise survival analysis. Risk scores including genetic, demographic, behavioral, and ocular factors were derived for 3 AMD endpoints and were validated and calibrated in a large independent cohort. Vision loss of 15 or more letters was evaluated as a new endpoint in genetic analyses. RESULTS Eight common and rare variants in genes CFH, C3, ARMS2, COL8A1, and HSPH1/B3GALTL conferred a significantly higher risk of transition to advanced AMD. Three loci (C2, CFB, RAD51B) were associated with lower rate of progression. A protective effect was suggested for CTRB1 and PELI3. The age-adjusted area under the curve (AUC) for the composite model including 13 loci model was 0.900 over 12 years (0.896 in the validation cohort). Generally, progressors had a higher risk category and nonprogressors had a lower risk category when genetic factors were considered. Furthermore, there was heterogeneity between models for GA and NV. The model was calibrated in the validation cohort. Determinants of visual loss included age, education, body mass index, smoking, and several common and rare genetic variants. CONCLUSION Eyes with the same baseline macular grade had a wide range of estimated probability of subsequent progression and visual loss based on the validated risk score. Identifying high-risk individuals at an earlier stage using predictive modeling could lead to improved preventive and therapeutic strategies in the era of precision medicine.
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Affiliation(s)
- Johanna M Seddon
- Department of Ophthalmology and Visual Sciences, University of Massachusetts Medical School, Worcester, Massachusetts, USA.
| | - Bernard Rosner
- Channing Division of Network Medicine, Department of Medicine, Harvard Medical School, Boston, Massachusetts, USA
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Rodrigues GA, Shalaev E, Karami TK, Cunningham J, Slater NKH, Rivers HM. Pharmaceutical Development of AAV-Based Gene Therapy Products for the Eye. Pharm Res 2018; 36:29. [PMID: 30591984 PMCID: PMC6308217 DOI: 10.1007/s11095-018-2554-7] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/30/2018] [Indexed: 12/18/2022]
Abstract
A resurgence of interest and investment in the field of gene therapy, driven in large part by advances in viral vector technology, has recently culminated in United States Food and Drug Administration approval of the first gene therapy product targeting a disease caused by mutations in a single gene. This product, LUXTURNA™ (voretigene neparvovec-rzyl; Spark Therapeutics, Inc., Philadelphia, PA), delivers a normal copy of the RPE65 gene to retinal cells for the treatment of biallelic RPE65 mutation–associated retinal dystrophy, a blinding disease. Many additional gene therapy programs targeting both inherited retinal diseases and other ocular diseases are in development, owing to an improved understanding of the genetic basis of ocular disease and the unique properties of the ocular compartment that make it amenable to local gene therapy. Here we review the growing body of literature that describes both the design and development of ocular gene therapy products, with a particular emphasis on target and vector selection, and chemistry, manufacturing, and controls.
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Affiliation(s)
| | - Evgenyi Shalaev
- Pharmaceutical Research and Development, Allergan plc, 2525 Dupont Drive, Irvine, California, 92612-1531, USA
| | - Thomas K Karami
- Pharmaceutical Research and Development, Allergan plc, 2525 Dupont Drive, Irvine, California, 92612-1531, USA
| | - James Cunningham
- Pharmaceutical Research and Development, Allergan plc, 2525 Dupont Drive, Irvine, California, 92612-1531, USA
| | - Nigel K H Slater
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 0AS, UK
| | - Hongwen M Rivers
- Pharmaceutical Research and Development, Allergan plc, 2525 Dupont Drive, Irvine, California, 92612-1531, USA.
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Lu F, Liu S, Hao Q, Liu L, Zhang J, Chen X, Hu W, Huang P. Association Between Complement Factor C2/C3/CFB/CFH Polymorphisms and Age-Related Macular Degeneration: A Meta-Analysis. Genet Test Mol Biomarkers 2018; 22:526-540. [PMID: 30179527 DOI: 10.1089/gtmb.2018.0110] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Several previous studies have assessed the contribution of polymorphisms in genes encoding the complement factors C2/C3/CFB/CFH with the risk of age-related macular degeneration (AMD), however the results have been inconsistent. We conducted a meta-analysis to systematically review the potential association between complement factor polymorphisms and AMD. METHODS Studies that investigated associations between C2 (rs547154 and rs9332739), C3 (rs1047286), CFB (rs4151667 and rs641153), and CFH (rs551397 and rs2274700) polymorphisms and AMD were identified by searching PubMed, EMBASE, Web of Science, and Cochrane Library databases for articles published prior to January 1, 2018. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to evaluate the association between these polymorphisms and AMD using Stata 12.0 software. Q and I2 statistics were used to evaluate between-study heterogeneity. Publication bias analyses were conducted using Begg's test. We also conducted an ethnic subgroup analysis. RESULTS A total of 53 studies that included data for 53,774 patients and 56,973 healthy controls were evaluated. The pooled ORs for rs551397, rs2274700, rs4151667, rs641153, rs1047286, rs9332739, and rs547154 in the heterozygote model were 0.53 (95% CI: 0.45-0.61), 0.53 (95% CI: 0.40-0.70), 0.54 (95% CI: 0.46-0.63), 0.48 (95% CI: 0.4-0.57), 1.42 (95% CI: 1.22-1.66), 0.5 (95% CI: 0.45-0.56), and 0.52 (95% CI: 0.43-0.62), respectively. CONCLUSION Our findings from this analysis confirmed the protective role of C2/CFB/CFH polymorphisms in the development of AMD, but showed that the single nucleotide polymorphism in C3 was a high-risk factor for AMD. The racial analysis results suggested that the effect of variant alleles was stronger in Caucasians than Asians.
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Affiliation(s)
- Feiteng Lu
- 1 Department of Biochemistry, College of Medicine, Nanchang University , Nanchang, P.R. China
| | - Shuang Liu
- 1 Department of Biochemistry, College of Medicine, Nanchang University , Nanchang, P.R. China
| | - Qingyun Hao
- 1 Department of Biochemistry, College of Medicine, Nanchang University , Nanchang, P.R. China
| | - Lixia Liu
- 2 Department of Internal Medicine, Youhao District People's Hospital , Yichun, P.R. China
| | - Jing Zhang
- 3 Department of Clinical Laboratory, The Second Affiliated Hospital of Nanchang University , Nanchang, P.R. China
| | - Xiaolong Chen
- 4 Department of Epidemiology, School of Public Health, Nanchang University , Nanchang, P.R. China
| | - Wang Hu
- 4 Department of Epidemiology, School of Public Health, Nanchang University , Nanchang, P.R. China
| | - Peng Huang
- 4 Department of Epidemiology, School of Public Health, Nanchang University , Nanchang, P.R. China .,5 Jiangxi Province Key Laboratory of Preventive Medicine, School of Public Health, Nanchang University , Nanchang, P.R. China
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Triebwasser MP, Wu X, Bertram P, Hourcade DE, Nelson DM, Atkinson JP. Timing and mechanism of conceptus demise in a complement regulatory membrane protein deficient mouse. Am J Reprod Immunol 2018; 80:e12997. [PMID: 29924462 PMCID: PMC6160323 DOI: 10.1111/aji.12997] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 05/24/2018] [Indexed: 01/01/2023] Open
Abstract
PROBLEM Crry is a widely expressed type 1 transmembrane complement regulatory protein in rodents which protects self-tissue by downregulating C3 activation. Crry-/- concepti produced by Crry+/- × Crry+/- matings are attacked by maternal complement system leading to loss before day 10. The membrane attack complex is not the mediator of this death. We hypothesized that the ability of C3b to engage the alternative pathway's feedback loop relatively unchecked on placental membranes induces the lesion yielding the demise of the Crry-/- mouse. METHOD OF STUDY We investigated the basis of Crry-/- conceptus demise by depleting maternal complement with cobra venom factor and blocking antibodies. We monitored their effects primarily by genotyping and histologic analyses. RESULTS We narrowed the critical period of the complement effect from 6.5 to 8.5 days post-coitus (dpc), which is immediately after the conceptus is exposed to maternal blood. Deposition by 5.5 dpc of maternal C3b on the placental vasculature lacking Crry-/- yielded loss of the conceptus by 8.5 dpc. Fusion of the allantois to the chorion during placental assembly did not occur, fetal vessels originating in the allantois did not infiltrate the chorioallantoic placenta, the chorionic plate failed to develop, and the labyrinthine component of the placenta did not mature. CONCLUSION Our data are most consistent with the deposition of C3b being responsible for the failure of the allantois to fuse to the chorion leading to subsequent conceptus demise.
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Affiliation(s)
- Michael P Triebwasser
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - Xiaobo Wu
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - Paula Bertram
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - Dennis E Hourcade
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | - Donald Michael Nelson
- Department of Obstetrics and Gynecology, Division of Maternal-Fetal Medicine, Ultrasound and Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - John P Atkinson
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
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46
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Notaro R, Sica M. C3-mediated extravascular hemolysis in PNH on eculizumab: Mechanism and clinical implications. Semin Hematol 2018; 55:130-135. [PMID: 30032749 DOI: 10.1053/j.seminhematol.2018.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 05/29/2018] [Indexed: 12/26/2022]
Abstract
The introduction of eculizumab, a human monoclonal antibody against the C5 component of complement, has changed radically the management of paroxysmal nocturnal hemoglobinuria (PNH). The blockade of the terminal complement pathway by eculizumab abrogates intravascular hemolysis, reduces the transfusion requirement and the risk of thrombosis in most of hemolytic PNH patients. However, in almost all PNH patients on eculizumab arises a fraction of PNH red cells that bind fragments of C3 and become a potential target of phagocytosis by macrophages. Eventually, this phagocytosis results in a variable degree of extravascular hemolysis that may reduce clinical benefits of eculizumab and, in fact, about one-fourth of patients remain transfusion-dependent. The treatment of the few PNH patients in which this de novo extravascular hemolysis become clinically relevant is still unsatisfactory. Nevertheless, the investigations of the mechanisms responsible of the extravascular hemolysis on eculizumab have resulted in the development of novel strategies for complement blockade that could overcome this condition.
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Affiliation(s)
- Rosario Notaro
- Laboratory of Cancer Genetics and Gene Transfer, Core Research Laboratory - Istituto per lo Studio, la Prevenzione e la Rete Oncologica (ISPRO), Florence, Italy.
| | - Michela Sica
- Laboratory of Cancer Genetics and Gene Transfer, Core Research Laboratory - Istituto per lo Studio, la Prevenzione e la Rete Oncologica (ISPRO), Florence, Italy
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Arslan J, Baird PN. Changing vision: a review of pharmacogenetic studies for treatment response in age-related macular degeneration patients. Pharmacogenomics 2018; 19:435-461. [DOI: 10.2217/pgs-2017-0183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Nonresponsiveness to age-related macular degeneration (AMD) treatments has become a growing concern in ophthalmology. Disparity among publications that have assessed pharmacogenetic (PGx) connections between AMD disease genes and treatments has delayed the implementation of PGx testing in AMD. We assessed all AMD PGx publications to identify the degree of agreement for publications within similar ethnic cohorts and worldwide, and the causes for differences in study outcomes. There are no accepted genotype–phenotype correlations, either within similar ethnic cohorts or worldwide. The diversity of measured outcomes, treatment protocols and statistical methods used may be causing this discrepancy. A universally accepted treatment protocol and the creation of agreed response group classification may bridge the gap between AMD PGx publications.
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Affiliation(s)
- Janan Arslan
- Department of Surgery (Ophthalmology), Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye & Ear Hospital, East Melbourne, Victoria, 3002, Australia
| | - Paul N Baird
- Department of Surgery (Ophthalmology), Centre for Eye Research Australia, University of Melbourne, Royal Victorian Eye & Ear Hospital, East Melbourne, Victoria, 3002, Australia
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48
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Wu X, Hutson I, Akk AM, Mascharak S, Pham CTN, Hourcade DE, Brown R, Atkinson JP, Harris CA. Contribution of Adipose-Derived Factor D/Adipsin to Complement Alternative Pathway Activation: Lessons from Lipodystrophy. THE JOURNAL OF IMMUNOLOGY 2018. [PMID: 29531168 DOI: 10.4049/jimmunol.1701668] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Factor D (FD) is an essential component of the complement alternative pathway (AP). It is an attractive pharmaceutical target because it is an AP-specific protease circulating in blood. Most components of the complement activation pathways are produced by the liver, but FD is highly expressed by adipose tissue. Two critical questions are: 1) to what degree does adipose tissue contribute to circulating FD levels and 2) what quantity of FD is sufficient to maintain a functional AP? To address these issues, we studied a novel mouse strain with complete lipodystrophy (LD), the fld mouse with partial LD, an FD-deficient mouse, and samples from lipodystrophic patients. FD was undetectable in the serum of LD mice, which also showed minimal AP function. Reconstitution with purified FD, serum mixing experiments, and studies of partial LD mice all demonstrated that a low level of serum FD is sufficient for normal AP activity in the mouse system. This conclusion was further supported by experiments in which wild-type adipose precursors were transplanted into LD mice. Our results indicate that almost all FD in mouse serum is derived from adipose tissue. In contrast, FD levels were reduced ∼50% in the sera of patients with congenital generalized LD. Our studies further demonstrate that a relatively small amount of serum FD is sufficient to facilitate significant time-dependent AP activity in humans and in mice. Furthermore, this observation highlights the potential importance of obtaining nearly complete inhibition of FD in treating alternative complement activation in various autoimmune and inflammatory human diseases.
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Affiliation(s)
- Xiaobo Wu
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110;
| | - Irina Hutson
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Antonina M Akk
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Smita Mascharak
- Department of Medicine, David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90095
| | - Christine T N Pham
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110.,Section of Rheumatology, Department of Medicine, St. Louis Veterans Affairs Medical Center, St. Louis, MO 63106
| | - Dennis E Hourcade
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Rebecca Brown
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20814; and
| | - John P Atkinson
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Charles A Harris
- Division of Endocrinology, Metabolism and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110; .,Section of Endocrinology, Department of Medicine, St. Louis Veterans Affairs Medical Center, St. Louis, MO 63106
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C-reactive protein and pentraxin-3 binding of factor H-like protein 1 differs from complement factor H: implications for retinal inflammation. Sci Rep 2018; 8:1643. [PMID: 29374201 PMCID: PMC5786067 DOI: 10.1038/s41598-017-18395-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 12/11/2017] [Indexed: 12/31/2022] Open
Abstract
Retinal inflammation plays a key role in the progression of age-related macular degeneration (AMD), a condition that leads to loss of central vision. The deposition of the acute phase pentraxin C-reactive protein (CRP) in the macula activates the complement system, thereby contributing to dysregulated inflammation. The complement protein factor H (FH) can bind CRP and down-regulate an inflammatory response. However, it is not known whether a truncated form of FH, called factor H-like protein 1 (FHL-1), which plays a significant regulatory role in the eye, also interacts with CRP. Here, we compare the binding properties of FHL-1 and FH to both CRP and the related protein pentraxin-3 (PTX3). We find that, unlike FH, FHL-1 can bind pro-inflammatory monomeric CRP (mCRP) as well as the circulating pentameric form. Furthermore, the four-amino acid C-terminal tail of FHL-1 (not present in FH) plays a role in mediating its binding to mCRP. PTX3 was found to be present in the macula of donor eyes and the AMD-associated Y402H polymorphism altered the binding of FHL-1 to PTX3. Our findings reveal that the binding characteristics of FHL-1 differ from those of FH, likely underpinning independent immune regulatory functions in the context of the human retina.
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50
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Clark SJ, McHarg S, Tilakaratna V, Brace N, Bishop PN. Bruch's Membrane Compartmentalizes Complement Regulation in the Eye with Implications for Therapeutic Design in Age-Related Macular Degeneration. Front Immunol 2017; 8:1778. [PMID: 29312308 PMCID: PMC5742201 DOI: 10.3389/fimmu.2017.01778] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/28/2017] [Indexed: 11/13/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in the western world and affects nearly 200 million people globally. Local inflammation driven by complement system dysregulation is currently a therapeutic target. Bruch’s membrane (BrM) is a sheet of extracellular matrix that separates the retina from the underlying choroid, a highly vascularized layer that supplies oxygen and nutrition to the outer retina. Here, we show that most complement proteins are unable to diffuse through BrM, although FHL-1, factor D and C5a can. AMD-associated lipid deposition in BrM decreases FHL-1 diffusion. We show that this impermeability of BrM creates two separate semi-independent compartments with respect to complement activation and regulation. Complement proteins synthesized locally on either side of BrM, or on the choroidal side if derived from the circulation, predominantly remain on their side of origin. As previous studies suggest that complement activation in AMD is confined to the choroidal side of BrM, we propose a model whereby complement activation in the choriocapillaris layer of the choroid generates C5a, which crosses BrM to interact with its specific receptor on RPE cells to initiate an inflammatory response in the retina. Understanding mechanisms underpinning AMD is essential for developing therapeutics that target the right molecule in the right anatomical compartment.
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Affiliation(s)
- Simon J Clark
- Division of Evolution and Genomic Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Selina McHarg
- Division of Evolution and Genomic Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Viranga Tilakaratna
- Division of Evolution and Genomic Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Nicole Brace
- Division of Evolution and Genomic Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Paul N Bishop
- Division of Evolution and Genomic Medicine, Faculty of Biology Medicine and Health, School of Biological Sciences, University of Manchester, Manchester, United Kingdom.,Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
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