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Hoppe C, Gregory-Ksander M. The Role of Complement Dysregulation in Glaucoma. Int J Mol Sci 2024; 25:2307. [PMID: 38396986 PMCID: PMC10888626 DOI: 10.3390/ijms25042307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 02/03/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Glaucoma is a progressive neurodegenerative disease characterized by damage to the optic nerve that results in irreversible vision loss. While the exact pathology of glaucoma is not well understood, emerging evidence suggests that dysregulation of the complement system, a key component of innate immunity, plays a crucial role. In glaucoma, dysregulation of the complement cascade and impaired regulation of complement factors contribute to chronic inflammation and neurodegeneration. Complement components such as C1Q, C3, and the membrane attack complex have been implicated in glaucomatous neuroinflammation and retinal ganglion cell death. This review will provide a summary of human and experimental studies that document the dysregulation of the complement system observed in glaucoma patients and animal models of glaucoma driving chronic inflammation and neurodegeneration. Understanding how complement-mediated damage contributes to glaucoma will provide opportunities for new therapies.
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Affiliation(s)
- Cindy Hoppe
- Schepens Eye Research Institute of Mass Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA;
- Animal Physiology/Neurobiology, Department of Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Meredith Gregory-Ksander
- Schepens Eye Research Institute of Mass Eye and Ear, Department of Ophthalmology, Harvard Medical School, Boston, MA 02114, USA;
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Tsai T, Reinehr S, Deppe L, Strubbe A, Kluge N, Dick HB, Joachim SC. Glaucoma Animal Models beyond Chronic IOP Increase. Int J Mol Sci 2024; 25:906. [PMID: 38255979 PMCID: PMC10815097 DOI: 10.3390/ijms25020906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/04/2024] [Accepted: 01/08/2024] [Indexed: 01/24/2024] Open
Abstract
Glaucoma is a complex and multifactorial disease defined as the loss of retinal ganglion cells (RGCs) and their axons. Besides an elevated intraocular pressure (IOP), other mechanisms play a pivotal role in glaucoma onset and progression. For example, it is known that excitotoxicity, immunological alterations, ischemia, and oxidative stress contribute to the neurodegeneration in glaucoma disease. To study these effects and to discover novel therapeutic approaches, appropriate animal models are needed. In this review, we focus on various glaucoma animal models beyond an elevated IOP. We introduce genetically modified mice, e.g., the optineurin E50K knock-in or the glutamate aspartate transporter (GLAST)-deficient mouse. Excitotoxicity can be mimicked by injecting the glutamate analogue N-methyl-D-aspartate intravitreally, which leads to rapid RGC degeneration. To explore the contribution of the immune system, the experimental autoimmune glaucoma model can serve as a useful tool. Here, immunization with antigens led to glaucoma-like damage. The ischemic mechanism can be mimicked by inducing a high IOP for a certain amount of time in rodents, followed by reperfusion. Thereby, damage to the retina and the optic nerve occurs rapidly after ischemia/reperfusion. Lastly, we discuss the importance of optic nerve crush models as model systems for normal-tension glaucoma. In summary, various glaucoma models beyond IOP increase can be utilized.
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Affiliation(s)
| | | | | | | | | | | | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany; (T.T.); (S.R.); (L.D.); (N.K.); (H.B.D.)
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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: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Erb C, Reinehr S, Theiss C, Dick HB, Joachim SC. HSP27 induced glaucomatous damage in mice of young and advanced age. Front Cell Neurosci 2023; 17:1257297. [PMID: 37744880 PMCID: PMC10513106 DOI: 10.3389/fncel.2023.1257297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 08/25/2023] [Indexed: 09/26/2023] Open
Abstract
Introduction Age-related diseases such as glaucoma, a leading cause of blindness, are having an upward trend due to an aging society. In glaucoma, some patients display altered antibody profiles and increased antibody titers, for example against heat shock protein 27 (HSP27). An intravitreal injection of HSP27 leads to glaucoma-like damage in rats. We now aimed to investigate if aged mice are more prone to this damage than younger ones. Methods We intravitreally injected HSP27 into young (1-2 months) and aged (7-8 months) mice to compare glaucomatous damage. Respective age-matched controls received PBS. Not injected eyes served as naive controls. Results Optical coherence tomography 4 weeks after injection showed no changes in retinal thickness in all groups at both ages. Cell counts and RT-qPCR revealed a significant reduction in RGC numbers in HSP27 mice at both ages. Comparing aged and young HSP27 mice, no differences in Rbpms and Pou4f1 (RGCs) expression was detected, while the Tubb3 expression (neuronal cells) was significantly upregulated in aged HSP27 animals. Neither microglia/macrophages nor (resident) microglia counts revealed significant differences in HSP27 mice at both ages. Nevertheless, increased relative Iba1 and Tmem119 expression was detected in young and aged HSP27 mice. Aged HSP27 mice displayed a significantly lower Iba1 expression than young ones, whereas Cd68 levels were upregulated. A larger GFAP+ area and an upregulation of GFAP expression in HSP27 animals of both ages indicated a macrogliosis. Also, elevated Il1b and Nos2 expression levels were observed in young and aged HSP27 mice. However, only Il1b levels were upregulated when comparing 7-8 months to 1-2 months old animals. A larger HSP25+ area was seen in aged HSP27 animals, while Hspb2 expression levels were downregulated in both HSP27 groups. The aged HSP27 group displayed an upregulated Hspb2 expression compared to young mice. Furthermore, a higher optic nerve degeneration score was noted in young and aged HSP27 groups. Discussion These findings indicate that an intravitreal injection of HSP27 led to RGC loss accompanied by inflammation. Age-dependent effects (7-8 months vs. 1-2 months) were not very prominent. The results suggest a potential role of extracellular HSP27 in the development of glaucoma.
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Affiliation(s)
- Clivia Erb
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Carsten Theiss
- Institute of Anatomy, Department of Cytology, Ruhr-University Bochum, Bochum, Germany
| | - H. Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
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Buonfiglio F, Pfeiffer N, Gericke A. Immunomodulatory and Antioxidant Drugs in Glaucoma Treatment. Pharmaceuticals (Basel) 2023; 16:1193. [PMID: 37765001 PMCID: PMC10535738 DOI: 10.3390/ph16091193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/02/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Glaucoma, a group of diseases characterized by progressive retinal ganglion cell loss, cupping of the optic disc, and a typical pattern of visual field defects, is a leading cause of severe visual impairment and blindness worldwide. Elevated intraocular pressure (IOP) is the leading risk factor for glaucoma development. However, glaucoma can also develop at normal pressure levels. An increased susceptibility of retinal ganglion cells to IOP, systemic vascular dysregulation, endothelial dysfunction, and autoimmune imbalances have been suggested as playing a role in the pathophysiology of normal-tension glaucoma. Since inflammation and oxidative stress play a role in all forms of glaucoma, the goal of this review article is to present an overview of the inflammatory and pro-oxidant mechanisms in the pathophysiology of glaucoma and to discuss immunomodulatory and antioxidant treatment approaches.
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Affiliation(s)
- Francesco Buonfiglio
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany;
| | | | - Adrian Gericke
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany;
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Reinehr S, Mueller-Buehl A. Apoptotic retinal ganglion cell loss is accompanied by complement and cytokine response in the βB1-CTGF primary open-angle glaucoma mouse model. Neural Regen Res 2023; 18:337-338. [PMID: 35900424 PMCID: PMC9396493 DOI: 10.4103/1673-5374.343911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Murenu E, Gerhardt MJ, Biel M, Michalakis S. More than meets the eye: The role of microglia in healthy and diseased retina. Front Immunol 2022; 13:1006897. [PMID: 36524119 PMCID: PMC9745050 DOI: 10.3389/fimmu.2022.1006897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/11/2022] [Indexed: 11/30/2022] Open
Abstract
Microglia are the main resident immune cells of the nervous system and as such they are involved in multiple roles ranging from tissue homeostasis to response to insults and circuit refinement. While most knowledge about microglia comes from brain studies, some mechanisms have been confirmed for microglia cells in the retina, the light-sensing compartment of the eye responsible for initial processing of visual information. However, several key pieces of this puzzle are still unaccounted for, as the characterization of retinal microglia has long been hindered by the reduced population size within the retina as well as the previous lack of technologies enabling single-cell analyses. Accumulating evidence indicates that the same cell type may harbor a high degree of transcriptional, morphological and functional differences depending on its location within the central nervous system. Thus, studying the roles and signatures adopted specifically by microglia in the retina has become increasingly important. Here, we review the current understanding of retinal microglia cells in physiology and in disease, with particular emphasis on newly discovered mechanisms and future research directions.
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Affiliation(s)
- Elisa Murenu
- Department of Ophthalmology, Klinikum der Ludwig-Maximilians-Universität München, Munich, Germany,*Correspondence: Elisa Murenu, ; ; Stylianos Michalakis,
| | | | - Martin Biel
- Department of Pharmacy, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stylianos Michalakis
- Department of Ophthalmology, Klinikum der Ludwig-Maximilians-Universität München, Munich, Germany,*Correspondence: Elisa Murenu, ; ; Stylianos Michalakis,
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Reinehr S, Safaei A, Grotegut P, Guntermann A, Tsai T, Hahn SA, Kösters S, Theiss C, Marcus K, Dick HB, May C, Joachim SC. Heat Shock Protein Upregulation Supplemental to Complex mRNA Alterations in Autoimmune Glaucoma. Biomolecules 2022; 12:biom12101538. [PMID: 36291747 PMCID: PMC9599116 DOI: 10.3390/biom12101538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 10/10/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
Glaucomatous optic neuropathy is a common cause for blindness. An elevated intraocular pressure is the main risk factor, but also a contribution of the immune system seems likely. In the experimental autoimmune glaucoma model used here, systemic immunization with an optic nerve homogenate antigen (ONA) leads to retinal ganglion cell (RGC) and optic nerve degeneration. We processed retinae for quantitative real-time PCR and immunohistology 28 days after immunization. Furthermore, we performed mRNA profiling in this model for the first time. We detected a significant RGC loss in the ONA retinae. This was accompanied by an upregulation of mRNA expression of genes belonging to the heat shock protein family. Furthermore, mRNA expression levels of the genes of the immune system, such as C1qa, C1qb, Il18, and Nfkb1, were upregulated in ONA animals. After laser microdissection, inner retinal layers were used for mRNA microarrays. Nine of these probes were significantly upregulated in ONA animals (p < 0.05), including Hba-a1 and Cxcl10, while fifteen probes were significantly downregulated in ONA animals (p < 0.05), such as Gdf15 and Wwox. Taken together, these findings provide further insights into the pivotal role of the immune response in glaucomatous optic neuropathy and could help to identify novel diagnostic or therapeutic strategies.
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Affiliation(s)
- Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Armin Safaei
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Pia Grotegut
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Annika Guntermann
- Department Functional Proteomics, Medizinisches Proteom-Center, Ruhr-University Bochum, ProDi E2.227, Gesundheitscampus 4, 44801 Bochum, Germany
| | - Teresa Tsai
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Stephan A. Hahn
- Department of Molecular GI Oncology, Faculty of Medicine, Ruhr-University Bochum, 44780 Bochum, Germany
| | - Steffen Kösters
- Department Functional Proteomics, Medizinisches Proteom-Center, Ruhr-University Bochum, ProDi E2.227, Gesundheitscampus 4, 44801 Bochum, Germany
| | - Carsten Theiss
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Universitaetsstr. 150, 44801 Bochum, Germany
| | - Katrin Marcus
- Department Functional Proteomics, Medizinisches Proteom-Center, Ruhr-University Bochum, ProDi E2.227, Gesundheitscampus 4, 44801 Bochum, Germany
| | - H. Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Caroline May
- Department Functional Proteomics, Medizinisches Proteom-Center, Ruhr-University Bochum, ProDi E2.227, Gesundheitscampus 4, 44801 Bochum, Germany
- Correspondence: (C.M.); (S.C.J.); Tel.: +49-234-24651 (C.M.); Tel.: +49-234-2993156 (S.C.J.)
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
- Correspondence: (C.M.); (S.C.J.); Tel.: +49-234-24651 (C.M.); Tel.: +49-234-2993156 (S.C.J.)
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Tonner H, Hunn S, Auler N, Schmelter C, Beutgen VM, von Pein HD, Pfeiffer N, Grus FH. A Monoclonal Anti-HMGB1 Antibody Attenuates Neurodegeneration in an Experimental Animal Model of Glaucoma. Int J Mol Sci 2022; 23. [PMID: 35456925 DOI: 10.3390/ijms23084107] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 04/02/2022] [Accepted: 04/05/2022] [Indexed: 02/06/2023] Open
Abstract
Neuroinflammation is a crucial process for the loss of retinal ganglion cells (RGC), a major characteristic of glaucoma. High expression of high-mobility group box protein 1 (HMGB1) plays a detrimental role in inflammatory processes and is elevated in the retinas of glaucoma patients. Therefore, this study aimed to investigate the effects of the intravitreal injection of an anti-HMGB1 monoclonal antibody (anti-HMGB1 Ab) in an experimental animal model of glaucoma. Two groups of Spraque Dawley rats received episcleral vein occlusion to chronically elevate intraocular pressure (IOP): (1) the IgG group, intravitreal injection of an unspecific IgG as a control, n = 5, and (2) the HMGB1 group, intravitreal injection of an anti-HMGB1 Ab, n = 6. IOP, retinal nerve fiber layer thickness (RNFLT), and the retinal flash response were monitored longitudinally. Post-mortem examinations included immunohistochemistry, microarray, and mass spectrometric analysis. RNFLT was significantly increased in the HMGB1 group compared with the IgG group (p < 0.001). RGC density showed improved neuronal cell survival in the retina in HMGB1 compared with the IgG group (p < 0.01). Mass spectrometric proteomic analysis of retinal tissue showed an increased abundance of RNA metabolism-associated heterogeneous nuclear ribonucleoproteins (hnRNPs), such as hnRNP U, D, and H2, in animals injected with the anti-HMGB1 Ab, indicating that the application of the antibody may cause increased gene expression. Microarray analysis showed a significantly decreased expression of C-X-C motif chemokine ligand 8 (CXCL8, p < 0.05) and connective tissue growth factor (CTGF, p < 0.01) in the HMGB1 group. Thus, these data suggest that intravitreal injection of anti-HMGB1 Ab reduced HMGB1-dependent inflammatory signaling and mediated RGC neuroprotection.
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10
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Cong Q, Soteros BM, Huo A, Li Y, Tenner AJ, Sia GM. C1q and SRPX2 regulate microglia mediated synapse elimination during early development in the visual thalamus but not the visual cortex. Glia 2022; 70:451-465. [PMID: 34762332 PMCID: PMC8732326 DOI: 10.1002/glia.24114] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 10/06/2021] [Accepted: 10/25/2021] [Indexed: 12/16/2022]
Abstract
The classical complement cascade mediates synapse elimination in the visual thalamus during early brain development. However, whether the primary visual cortex also undergoes complement-mediated synapse elimination during early visual system development remains unknown. Here, we examined microglia-mediated synapse elimination in the visual thalamus and the primary visual cortex of early postnatal C1q and SRPX2 knockout mice. In the lateral geniculate nucleus, deletion of C1q caused a persistent decrease in synapse elimination and microglial synapse engulfment, while deletion of SRPX2 caused a transient increase in the same readouts. In the C1q-SRPX2 double knockout mice, the C1q knockout phenotypes were dominant over the SRPX2 knockout phenotypes, a result which is consistent with SRPX2 being an inhibitor of C1q. We found that genetic deletion of either C1q or SRPX2 did not affect synapse elimination or microglial engulfment of synapses in layer 4 of the primary visual cortex in early brain development. Together, these results show that the classical complement pathway regulates microglia-mediated synapse elimination in the visual thalamus but not the visual cortex during early development of the central nervous system.
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Affiliation(s)
- Qifei Cong
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA,Institutes of Neuroscience, Soochow University, Suzhou, China.,Corresponding author: ,
| | - Breeanne M. Soteros
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Anran Huo
- Institutes of Neuroscience, Soochow University, Suzhou, China
| | - Yang Li
- Department of Neurology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Andrea J. Tenner
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, USA,Department of Neurobiology and Behavior, University of California, Irvine, CA, USA.,Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA
| | - Gek Ming Sia
- Department of Pharmacology, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA,Corresponding author: ,
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Petrikowski L, Reinehr S, Haupeltshofer S, Deppe L, Graz F, Kleiter I, Dick HB, Gold R, Faissner S, Joachim SC. Progressive Retinal and Optic Nerve Damage in a Mouse Model of Spontaneous Opticospinal Encephalomyelitis. Front Immunol 2022; 12:759389. [PMID: 35140707 PMCID: PMC8818777 DOI: 10.3389/fimmu.2021.759389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 12/29/2021] [Indexed: 11/13/2022] Open
Abstract
Neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein-antibody-associated disease (MOGAD) are antibody mediated CNS disorders mostly affecting the optic nerve and spinal cord with potential severe impact on the visual pathway. Here, we investigated inflammation and degeneration of the visual system in a spontaneous encephalomyelitis animal model. We used double-transgenic (2D2/Th) mice which develop a spontaneous opticospinal encephalomyelitis (OSE). Retinal morphology and its function were evaluated via spectral domain optical coherence tomography (SD-OCT) and electroretinography (ERG) in 6- and 8-week-old mice. Immunohistochemistry of retina and optic nerve and examination of the retina via RT-qPCR were performed using markers for inflammation, immune cells and the complement pathway. OSE mice showed clinical signs of encephalomyelitis with an incidence of 75% at day 38. A progressive retinal thinning was detected in OSE mice via SD-OCT. An impairment in photoreceptor signal transmission occurred. This was accompanied by cellular infiltration and demyelination of optic nerves. The number of microglia/macrophages was increased in OSE optic nerves and retinas. Analysis of the retina revealed a reduced retinal ganglion cell number and downregulated Pou4f1 mRNA expression in OSE retinas. RT-qPCR revealed an elevation of microglia markers and the cytokines Tnfa and Tgfb. We also documented an upregulation of the complement system via the classical pathway. In summary, we describe characteristics of inflammation and degeneration of the visual system in a spontaneous encephalomyelitis model, characterized by coinciding inflammatory and degenerative mechanisms in both retina and optic nerve with involvement of the complement system.
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Affiliation(s)
- Laura Petrikowski
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Steffen Haupeltshofer
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
| | - Leonie Deppe
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Florian Graz
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
| | - Ingo Kleiter
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
| | - H. Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Ralf Gold
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
| | - Simon Faissner
- Department of Neurology, Ruhr-University Bochum, St. Josef-Hospital, Bochum, Germany
- *Correspondence: Simon Faissner, ; Stephanie C. Joachim,
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
- *Correspondence: Simon Faissner, ; Stephanie C. Joachim,
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Hunziker D, Reinehr S, Palmhof M, Wagner N, Biniasch T, Stute G, Mattei P, Schmitz P, DiGiorgio P, Hert J, Rudolph MG, Benz J, Stihle M, Gsell B, Müller S, Gasser R, Schonhoven N, Ullmer C, Joachim SC. Synthesis, Characterization, and in vivo Evaluation of a Novel Potent Autotaxin-Inhibitor. Front Pharmacol 2022; 12:699535. [PMID: 35126098 PMCID: PMC8807399 DOI: 10.3389/fphar.2021.699535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 11/30/2021] [Indexed: 11/13/2022] Open
Abstract
The autotaxin-lysophosphatidic acid (ATX-LPA) signaling pathway plays a role in a variety of autoimmune diseases, such as rheumatoid arthritis or neurodegeneration. A link to the pathogenesis of glaucoma is suggested by an overactive ATX-LPA axis in aqueous humor samples of glaucoma patients. Analysis of such samples suggests that the ATX-LPA axis contributes to the fibrogenic activity and resistance to aqueous humor outflow through the trabecular meshwork. In order to inhibit or modulate this pathway, we developed a new series of ATX-inhibitors containing novel bicyclic and spirocyclic structural motifs. A potent lead compound (IC50 against ATX: 6 nM) with good in vivo PK, favorable in vitro property, and safety profile was generated. This compound leads to lowered LPA levels in vivo after oral administration. Hence, it was suitable for chronic oral treatment in two rodent models of glaucoma, the experimental autoimmune glaucoma (EAG) and the ischemia/reperfusion models. In the EAG model, rats were immunized with an optic nerve antigen homogenate, while controls received sodium chloride. Retinal ischemia/reperfusion (I/R) was induced by elevating the intraocular pressure (IOP) in one eye to 140 mmHg for 60 min, followed by reperfusion, while the other untreated eye served as control. Retinae and optic nerves were evaluated 28 days after EAG or 7 and 14 days after I/R induction. Oral treatment with the optimized ATX-inhibitor lead to reduced retinal ganglion cell (RGC) loss in both glaucoma models. In the optic nerve, the protective effect of ATX inhibition was less effective compared to the retina and only a trend to a weakened neurofilament distortion was detectable. Taken together, these results provide evidence that the dysregulation of the ATX-LPA axis in the aqueous humor of glaucoma patients, in addition to the postulated outflow impairment, might also contribute to RGC loss. The observation that ATX-inhibitor treatment in both glaucoma models did not result in significant IOP increases or decreases after oral treatment indicates that protection from RGC loss due to inhibition of the ATX-LPA axis is independent of an IOP lowering effect.
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Affiliation(s)
- Daniel Hunziker
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Marina Palmhof
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Natalie Wagner
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Thomas Biniasch
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Gesa Stute
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Patrizio Mattei
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Petra Schmitz
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Patrick DiGiorgio
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Jérôme Hert
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Markus G. Rudolph
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Joerg Benz
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Martine Stihle
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Bernard Gsell
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Stephan Müller
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
| | - Rodolfo Gasser
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Therapeutic Modalities, Small Molecule Research, Roche Innovation Center Basel, Basel, Switzerland
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Pharmaceutical Sciences, Roche Innovation Center Basel, Basel, Switzerland
| | - Nina Schonhoven
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Christoph Ullmer
- F. Hoffmann-La Roche Ltd., Pharma Research and Early Development, Ophthalmology Discovery, Roche Innovation Center Basel, Basel, Switzerland
- *Correspondence: Christoph Ullmer, ; Stephanie C. Joachim,
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
- *Correspondence: Christoph Ullmer, ; Stephanie C. Joachim,
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Li S, Qiu Y, Yu J, Shao M, Li Y, Cao W, Sun X. Serum complement component 3, complement component 4 and complement component 1q levels predict progressive visual field loss in older women with primary angle closure glaucoma. Br J Ophthalmol 2022; 107:828-835. [PMID: 35017157 DOI: 10.1136/bjophthalmol-2021-320541] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/10/2021] [Indexed: 01/07/2023]
Abstract
AIM To evaluate the association between serum levels of complement component (C) 3, C4 and C1q and visual field (VF) loss in patients with primary angle closure glaucoma (PACG). METHODS In this prospective cohort study, a total of 308 patients with PACG were included. The patients were followed up every 6 months (at least 2 years), with clinical examination and VF testing. Based on their sex and age, the subjects were stratified into male and female subgroups, and by age at <60 and ≥60 years per subgroup. RESULTS One hundred twenty-three (39.94%) patients showed glaucoma VF progression. The serum levels of C3, C4 and C1q were significantly lower (p<0.05) in the progression group compared with the non-progression group in the ≥60 years female subgroup. In female patients with age ≥60 years, (1) lower levels of baseline C3 (HR=0.98, p<0.001), C4 (HR=0.96, p=0.01) and C1q levels (HR=0.99, p=0.003) were associated with a greater risk of VF progression; (2) patients with lower C3 levels had significantly (p<0.05) higher rates of VF loss progression, similar to those with lower C4 and lower C1q levels; and (3) the generalised additive model revealed a negative correlation between baseline C3 (p<0.001), C4 (p<0.001) and C1q (p<0.001) levels with the risk of VF progression. No statistical significance was observed in the male (<60 and ≥60 years) and female (<60 years) subgroups. CONCLUSION Decreased C3, C4 and C1q levels at baseline were significantly associated with a greater risk of VF loss progression only in older women with PACG.
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Affiliation(s)
- Shengjie Li
- Department of Clinical Laboratory, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yichao Qiu
- Department of Clinical Laboratory, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jian Yu
- Department of Ophthalmology and Vision Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Mingxi Shao
- Department of Clinical Laboratory, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yingzhu Li
- Department of Clinical Laboratory, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wenjun Cao
- Department of Clinical Laboratory, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology and Vision Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, Institutes of Brain Science, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China.,NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
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Mueller-Buehl AM, Buehner T, Pfarrer C, Deppe L, Peters L, Dick BH, Joachim SC. Hypoxic Processes Induce Complement Activation via Classical Pathway in Porcine Neuroretinas. Cells 2021; 10:3575. [PMID: 34944083 DOI: 10.3390/cells10123575] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 12/14/2021] [Accepted: 12/15/2021] [Indexed: 02/06/2023] Open
Abstract
Considering the fact that many retinal diseases are yet to be cured, the pathomechanisms of these multifactorial diseases need to be investigated in more detail. Among others, oxidative stress and hypoxia are pathomechanisms that take place in retinal diseases, such as glaucoma, age-related macular degeneration, or diabetic retinopathy. In consideration of these diseases, it is also evidenced that the immune system, including the complement system and its activation, plays an important role. Suitable models to investigate neuroretinal diseases are organ cultures of porcine retina. Based on an established model, the role of the complement system was studied after the induction of oxidative stress or hypoxia. Both stressors led to a loss of retinal ganglion cells (RGCs) accompanied by apoptosis. Hypoxia activated the complement system as noted by higher C3+ and MAC+ cell numbers. In this model, activation of the complement cascade occurred via the classical pathway and the number of C1q+ microglia was increased. In oxidative stressed retinas, the complement system had no consideration, but strong inflammation took place, with elevated TNF, IL6, and IL8 mRNA expression levels. Together, this study shows that hypoxia and oxidative stress induce different mechanisms in the porcine retina inducing either the immune response or an inflammation. Our findings support the thesis that the immune system is involved in the development of retinal diseases. Furthermore, this study is evidence that both approaches seem suitable models to investigate undergoing pathomechanisms of several neuroretinal diseases.
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15
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Reinehr S, Doerner JD, Mueller-Buehl AM, Koch D, Fuchshofer R, Dick HB, Joachim SC. Cytokine and Complement Response in the Glaucomatous βB1-CTGF Mouse Model. Front Cell Neurosci 2021; 15:718087. [PMID: 34867198 PMCID: PMC8637215 DOI: 10.3389/fncel.2021.718087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
Glaucoma is a complex neurodegenerative disease leading to a loss of retinal ganglion cells (RGCs) and optic nerve axons. An activation of the complement system seems to contribute to cell loss in this disease. Hence, we investigated a possible initiation of the complement system and the cytokine response in the βB1-CTGF glaucoma model. In these mice, intraocular pressure is elevated, which is the main glaucoma risk factor in patients, and RGC loss occurs at 15 weeks of age. Therefore, quantitative real-time PCR and immunohistological experiments were performed in 5-, 10-, and 15-week-old βB1-CTGF animals and their corresponding wildtypes (WT) to analyze the expression of several complement system factors. We could show that mRNA levels of the terminal complement pathway components C3 and C5 (Hc) were upregulated at 10 weeks. In accordance, more C3+ and membrane attack complex+ cells were observed in transgenic retinae. Further, the C5a receptor anaphylatoxin receptor (C5ar) and the complement component C5a receptor 1 (C5ar1; CD88) mRNA levels were upregulated in 10- and 15-week-old βB1-CTGF mice. Interestingly, all three activation routes of the complement system were elevated in βB1-CTGF mice at some age. Especially C1q, as a marker of the classical pathway, was significantly increased at all investigated ages. Furthermore, mRNA expression levels of interferon-γ (Infg) were upregulated at 5 weeks, while Cxcl1 and Cxcl2 mRNA levels were upregulated at 10 and 15 weeks. The mRNA levels of the chemokines Cxcl10 were increased at all ages in βB1-CTGF mice. These results lead to the assumption that in these transgenic mice, a complement activation mainly through the classical pathway as well as a cytokine response plays a major role in cell death.
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Affiliation(s)
- Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Johanna D. Doerner
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Ana M. Mueller-Buehl
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Dennis Koch
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Rudolf Fuchshofer
- Institute of Human Anatomy and Embryology, University Regensburg, Regensburg, Germany
| | - H. Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C. Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
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16
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Guo M, Schwartz TD, Dunaief JL, Cui QN. Myeloid cells in retinal and brain degeneration. FEBS J 2021; 289:2337-2361. [PMID: 34478598 PMCID: PMC8891394 DOI: 10.1111/febs.16177] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 08/06/2021] [Accepted: 09/02/2021] [Indexed: 12/11/2022]
Abstract
Retinal inflammation underlies multiple prevalent ocular and neurological diseases. Similar inflammatory processes are observed in glaucomatous optic neuropathy, age-related macular degeneration, retinitis pigmentosa, posterior uveitis, Alzheimer's disease, and Parkinson's disease. In particular, human and animal studies have demonstrated the important role microglia/macrophages play in initiating and maintaining a pro-inflammatory environment in degenerative processes impacting vision. On the other hand, microglia have also been shown to have a protective role in multiple central nervous system diseases. Identifying the mechanisms underlying cell dysfunction and death is the first step toward developing novel therapeutics for these diseases impacting the central nervous system. In addition to reviewing recent key studies defining important mediators of retinal inflammation, with an emphasis on translational studies that bridge this research from bench to bedside, we also highlight a promising therapeutic class of medications, the glucagon-like peptide-1 receptor agonists. Finally, we propose areas where additional research is necessary to identify mechanisms that can be modulated to shift the balance from a neurotoxic to a neuroprotective retinal environment.
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Affiliation(s)
- Michelle Guo
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Turner D Schwartz
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Joshua L Dunaief
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
| | - Qi N Cui
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA
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Shestopalov VI, Spurlock M, Gramlich OW, Kuehn MH. Immune Responses in the Glaucomatous Retina: Regulation and Dynamics. Cells 2021; 10:1973. [PMID: 34440742 DOI: 10.3390/cells10081973] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/27/2021] [Accepted: 07/28/2021] [Indexed: 12/27/2022] Open
Abstract
Glaucoma is a multifactorial disease resulting in progressive vision loss due to retinal ganglion cell (RGC) dysfunction and death. Early events in the pathobiology of the disease include oxidative, metabolic, or mechanical stress that acts upon RGC, causing these to rapidly release danger signals, including extracellular ATP, resulting in micro- and macroglial activation and neuroinflammation. Danger signaling also leads to the formation of inflammasomes in the retina that enable maturation of proinflammatory cytokines such IL-1β and IL-18. Chronic neuroinflammation can have directly damaging effects on RGC, but it also creates a proinflammatory environment and compromises the immune privilege of the retina. In particular, continuous synthesis of proinflammatory mediators such as TNFα, IL-1β, and anaphylatoxins weakens the blood–retina barrier and recruits or activates T-cells. Recent data have demonstrated that adaptive immune responses strongly exacerbate RGC loss in animal models of the disease as T-cells appear to target heat shock proteins displayed on the surface of stressed RGC to cause their apoptotic death. It is possible that dysregulation of these immune responses contributes to the continued loss of RGC in some patients.
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18
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Duarte JN. Neuroinflammatory Mechanisms of Mitochondrial Dysfunction and Neurodegeneration in Glaucoma. J Ophthalmol 2021; 2021:4581909. [PMID: 33953963 DOI: 10.1155/2021/4581909] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2020] [Revised: 06/29/2020] [Accepted: 03/23/2021] [Indexed: 12/13/2022] Open
Abstract
The exact mechanism of retinal ganglion cell loss in the pathogenesis of glaucoma is yet to be understood. Mitochondrial damage-associated molecular patterns (DAMPs) resulting from mitochondrial dysfunction have been linked to Leber's hereditary optic neuropathy and autosomal dominant optic atrophy, as well as to brain neurodegenerative diseases. Recent evidence shows that, in conditions where mitochondria are damaged, a sustained inflammatory response and downstream pathological inflammation may ensue. Mitochondrial damage has been linked to the accumulation of age-related mitochondrial DNA mutations and mitochondrial dysfunction, possibly through aberrant reactive oxygen species production and defective mitophagy. The present review focuses on how mitochondrial dysfunction may overwhelm the ability of neurons and glial cells to adequately maintain homeostasis and how mitochondria-derived DAMPs trigger the immune system and induce neurodegeneration.
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Abstract
The complement system was discovered at the end of the 19th century as a heat-labile plasma component that "complemented" the antibodies in killing microbes, hence the name "complement." Complement is also part of the innate immune system, protecting the host by recognition of pathogen-associated molecular patterns. However, complement is multifunctional far beyond infectious defense. It contributes to organ development, such as sculpting neuron synapses, promoting tissue regeneration and repair, and rapidly engaging and synergizing with a number of processes, including hemostasis leading to thromboinflammation. Complement is a double-edged sword. Although it usually protects the host, it may cause tissue damage when dysregulated or overactivated, such as in the systemic inflammatory reaction seen in trauma and sepsis and severe coronavirus disease 2019 (COVID-19). Damage-associated molecular patterns generated during ischemia-reperfusion injuries (myocardial infarction, stroke, and transplant dysfunction) and in chronic neurologic and rheumatic disease activate complement, thereby increasing damaging inflammation. Despite the long list of diseases with potential for ameliorating complement modulation, only a few rare diseases are approved for clinical treatment targeting complement. Those currently being efficiently treated include paroxysmal nocturnal hemoglobinuria, atypical hemolytic-uremic syndrome, myasthenia gravis, and neuromyelitis optica spectrum disorders. Rare diseases, unfortunately, preclude robust clinical trials. The increasing evidence for complement as a pathogenetic driver in many more common diseases suggests an opportunity for future complement therapy, which, however, requires robust clinical trials; one ongoing example is COVID-19 disease. The current review aims to discuss complement in disease pathogenesis and discuss future pharmacological strategies to treat these diseases with complement-targeted therapies. SIGNIFICANCE STATEMENT: The complement system is the host's defense friend by protecting it from invading pathogens, promoting tissue repair, and maintaining homeostasis. Complement is a double-edged sword, since when dysregulated or overactivated it becomes the host's enemy, leading to tissue damage, organ failure, and, in worst case, death. A number of acute and chronic diseases are candidates for pharmacological treatment to avoid complement-dependent damage, ranging from the well established treatment for rare diseases to possible future treatment of large patient groups like the pandemic coronavirus disease 2019.
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Affiliation(s)
- Peter Garred
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
| | - Andrea J Tenner
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
| | - Tom E Mollnes
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
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Skopiński P, Radomska-Leśniewska DM, Izdebska J, Kamińska A, Kupis M, Kubiak AJ, Samelska K. New perspectives of immunomodulation and neuroprotection in glaucoma. Cent Eur J Immunol 2021; 46:105-10. [PMID: 33897291 DOI: 10.5114/ceji.2021.104329] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/21/2020] [Indexed: 02/07/2023] Open
Abstract
Glaucoma is the neurodegenerative disease of retinal ganglion cells. The main risk factor for glaucoma is increased intraocular pressure. The processes leading to cell death due to presence of the injury factor comprise multiple molecular mechanisms, as well as the immunological response. The knowledge of immunological mechanisms occurring in glaucomatous degeneration makes it possible to introduce glaucoma treatment modulating the cellular degradation. The glaucoma treatment of the future will make it possible not only to lower the intraocular pressure, but also to moderate the intracellular mechanisms in order to prevent retinal cell degeneration. Citicoline is a drug modulating glutamate excitotoxicity that is already in use. Rho kinase inhibitors were found to stimulate neurite growth and axon regeneration apart from lowering intraocular pressure. The complementary action of brimonidine is to increase neurotrophic factor (NTF) concentrations and inhibit glutamate toxicity. Immunomodulatory therapies with antibodies and gene therapies show promising effects in the current studies. The supplementation of NTFs prevents glaucomatous damage. Resveratrol and other antioxidants inhibit reactive oxygen species formation. Cell transplantation of stem cells, Schwann cells and nerve extracts was reported to be successful so far. Our review presents the most promising new strategies of neuroprotection and immunomodulation in glaucoma.
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21
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Weiss M, Reinehr S, Mueller-Buehl AM, Doerner JD, Fuchshofer R, Stute G, Dick HB, Joachim SC. Activation of Apoptosis in a βB1-CTGF Transgenic Mouse Model. Int J Mol Sci 2021; 22:1997. [PMID: 33671472 DOI: 10.3390/ijms22041997] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 02/09/2021] [Accepted: 02/12/2021] [Indexed: 11/23/2022] Open
Abstract
To reveal the pathomechanisms of glaucoma, a common cause of blindness, suitable animal models are needed. As previously shown, retinal ganglion cell and optic nerve degeneration occur in βB1-CTGF mice. Here, we aimed to determine possible apoptotic mechanisms and degeneration of different retinal cells. Hence, retinae were processed for immunohistology (n = 5–9/group) and quantitative real-time PCR analysis (n = 5–7/group) in 5- and 10-week-old βB1-CTGF and wildtype controls. We noted significantly more cleaved caspase 3+ cells in βB1-CTGF retinae at 5 (p = 0.005) and 10 weeks (p = 0.02), and a significant upregulation of Casp3 and Bax/Bcl2 mRNA levels (p < 0.05). Furthermore, more terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL+) cells were detected in transgenic mice at 5 (p = 0.03) and 10 weeks (p = 0.02). Neurofilament H staining (p = 0.01) as well as Nefh (p = 0.02) and Tubb3 (p = 0.009) mRNA levels were significantly decreased at 10 weeks. GABAergic synapse intensity was lower at 5 weeks, while no alterations were noted at 10 weeks. The glutamatergic synapse intensity was decreased at 5 (p = 0.007) and 10 weeks (p = 0.01). No changes were observed for bipolar cells, photoreceptors, and macroglia. We conclude that apoptotic processes and synapse loss precede neuronal death in this model. This slow progression rate makes the βB1-CTGF mice a suitable model to study primary open-angle glaucoma.
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22
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Quaranta L, Bruttini C, Micheletti E, Konstas AGP, Michelessi M, Oddone F, Katsanos A, Sbardella D, De Angelis G, Riva I. Glaucoma and neuroinflammation: An overview. Surv Ophthalmol 2021; 66:693-713. [PMID: 33582161 DOI: 10.1016/j.survophthal.2021.02.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/13/2022]
Abstract
Glaucoma is an optic neuropathy characterized by well-defined optic disc morphological changes (i.e., cup enlargement, neuroretinal border thinning, and notching, papillary vessel modifications) consequent to retinal ganglion cell loss, axonal degeneration, and lamina cribrosa remodeling. These modifications tend to be progressive and are the main cause of functional damage in glaucoma. Despite the latest findings about the pathophysiology of the disease, the exact trigger mechanisms and the mechanism of degeneration of retinal ganglion cells and their axons have not been completely elucidated. Neuroinflammation may play a role in both the development and the progression of the disease as a result of its effects on retinal environment and retinal ganglion cells. We summarize the latest findings about neuroinflammation in glaucoma and examine the connection between risk factors, neuroinflammation, and retinal ganglion cell degeneration.
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Affiliation(s)
- Luciano Quaranta
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy.
| | - Carlo Bruttini
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
| | - Eleonora Micheletti
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
| | - Anastasios G P Konstas
- 1st and 3rd University Departments of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | | | - Andreas Katsanos
- Department of Ophthalmology, University of Ioannina, Ioannina, Greece
| | | | - Giovanni De Angelis
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
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Hubens WHG, Beckers HJM, Gorgels TGMF, Webers CAB. Increased ratios of complement factors C3a to C3 in aqueous humor and serum mark glaucoma progression. Exp Eye Res 2021; 204:108460. [PMID: 33493474 DOI: 10.1016/j.exer.2021.108460] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/06/2021] [Accepted: 01/18/2021] [Indexed: 12/17/2022]
Abstract
INTRODUCTION We recently performed a combined analysis of publicly available proteomic studies of aqueous humor (AH) of patients with primary open angle glaucoma (POAG). This analysis revealed changes in complement protein concentrations in the AH of progressive POAG patients, which suggested that the complement system may play a role in POAG progression. As the proteomic studies could not provide information on the activity of the complement system, we addressed this question in the current study. METHODS Blood serum and AH were obtained from 30 patients: 10 progressive POAG, 10 stable POAG and, as controls, 10 cataract patients. Glaucoma patients with a visual field Mean Deviation (MD) change of at least 1.0 dB/year were considered progressive; a MD change of less than 0.5 dB/year was considered stable. The ratio between the levels of complement factors C3a and C3 was used as indicator for activation of the complement cascade. The factors were measured with commercially available ELISA kits. RESULTS AH levels of complement factors C3 and C3a did not significantly differ between groups. In serum, complement factor C3 did not differ between groups whereas C3a was significantly elevated in progressive POAG patients compared to controls (p < 0.05). The resulting complement C3a/C3 ratio was significantly higher in progressive POAG patients in both AH (p < 0.05) and serum (p < 0.01), and this ratio significantly correlated between the two body fluids (p < 0.001). Furthermore, there was a strong correlation between disease progression and C3a/C3 activation ratio both in AH (p < 0.01) and in serum (p < 0.001). The higher the complement C3a/C3 ratio, the faster the disease progression. CONCLUSION Significant increases in AH and serum complement C3a/C3 ratios were observed in progressive POAG patients but not in stable POAG patients. Furthermore, the complement C3a/C3 ratio correlated strongly with the rate of disease progression in both AH and serum. These findings suggest that activation of the complement system plays a role in glaucoma progression and that progressive glaucoma patients may have systemic changes in complement activation.
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Affiliation(s)
- W H G Hubens
- University Eye Clinic Maastricht, Maastricht Medical Center, Maastricht, the Netherlands; Research School of Mental Health and Neuroscience, Maastricht University, Maastricht, the Netherlands.
| | - H J M Beckers
- University Eye Clinic Maastricht, Maastricht Medical Center, Maastricht, the Netherlands
| | - T G M F Gorgels
- University Eye Clinic Maastricht, Maastricht Medical Center, Maastricht, the Netherlands
| | - C A B Webers
- University Eye Clinic Maastricht, Maastricht Medical Center, Maastricht, the Netherlands
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Borucki DM, Toutonji A, Couch C, Mallah K, Rohrer B, Tomlinson S. Complement-Mediated Microglial Phagocytosis and Pathological Changes in the Development and Degeneration of the Visual System. Front Immunol 2020; 11:566892. [PMID: 33072106 PMCID: PMC7541817 DOI: 10.3389/fimmu.2020.566892] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/17/2020] [Indexed: 12/21/2022] Open
Abstract
The focus of this review is the role of complement-mediated phagocytosis in retinal and neurological diseases affecting the visual system. Complement activation products opsonize synaptic material on neurons for phagocytic removal, which is a normal physiological process during development, but a pathological process in several neurodegenerative diseases and conditions. We discuss the role of complement in the refinement and elimination of synapses in the retina and lateral geniculate nucleus, both during development and in disease states. How complement and aberrant phagocytosis promotes injury to the visual system is discussed primarily in the context of multiple sclerosis, where it has been extensively studied, although the role of complement in visual dysfunction in other diseases such as stroke and traumatic brain injury is also highlighted. Retinal diseases are also covered, with a focus on glaucoma and age-related macular degeneration. Finally, we discuss the potential of complement inhibitory strategies to treat diseases affecting the visual system.
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Affiliation(s)
- Davis M. Borucki
- Medical Scientist Training Program, Medical University of South Carolina, Charleston, SC, United States
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
| | - Amer Toutonji
- Medical Scientist Training Program, Medical University of South Carolina, Charleston, SC, United States
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
| | - Christine Couch
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Khalil Mallah
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Baerbel Rohrer
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States
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Benning L, Reinehr S, Grotegut P, Kuehn S, Stute G, Dick HB, Joachim SC. Synapse and Receptor Alterations in Two Different S100B-Induced Glaucoma-Like Models. Int J Mol Sci 2020; 21:ijms21196998. [PMID: 32977518 PMCID: PMC7583988 DOI: 10.3390/ijms21196998] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 09/20/2020] [Indexed: 11/03/2022] Open
Abstract
Glaucoma is identified by an irreversible retinal ganglion cell (RGC) loss and optic nerve damage. Over the past few years, the immune system gained importance in its genesis. In a glaucoma-like animal model with intraocular S100B injection, RGC death occurs at 14 days. In an experimental autoimmune glaucoma model with systemic S100B immunization, a loss of RGCs is accompanied by a decreased synaptic signal at 28 days. Here, we aimed to study synaptic alterations in these two models. In one group, rats received a systemic S100B immunization (n = 7/group), while in the other group, S100B was injected intraocularly (n = 6–7/group). Both groups were compared to appropriate controls and investigated after 14 days. While inhibitory post-synapses remained unchanged in both models, excitatory post-synapses degenerated in animals with intraocular S100B injection (p = 0.03). Excitatory pre-synapses tendentially increased in animals with systemic S100B immunization (p = 0.08) and significantly decreased in intraocular ones (p = 0.04). Significantly more N-methyl-d-aspartate (NMDA) receptors (both p ≤ 0.04) as well as gamma-aminobutyric acid (GABA) receptors (both p < 0.03) were observed in S100B animals in both models. We assume that an upregulation of these receptors causes the interacting synapse types to degenerate. Heightened levels of excitatory pre-synapses could be explained by remodeling followed by degeneration.
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Sitnilska V, Enders P, Cursiefen C, Fauser S, Altay L. Association of imaging biomarkers and local activation of complement in aqueous humor of patients with early forms of age-related macular degeneration. Graefes Arch Clin Exp Ophthalmol 2021; 259:623-32. [PMID: 32876798 DOI: 10.1007/s00417-020-04910-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 12/16/2022] Open
Abstract
Purpose To investigate a possible correlation between established imaging biomarkers for age-related macular degeneration and local complement system activation, measured in aqueous humor (AH) of patients with early stages of age-related macular degeneration (AMD) and controls. Methods This analysis included prospectively acquired AH samples of 106 eyes (35 with early/intermediate AMD, 71 controls). The levels of complement protein 3 (C3), 4 (C4), 5 (C5); activation products of complement factor 3a (C3a) and Ba, C3b/iC3b; complement factors B, D, H, I (CFB, CFD, CFH, CFI); and total protein concentration were analyzed. Quantitative levels of complement factors were correlated to the presence of reticular pseudodrusen (RPD), the presence of hyperreflective foci (HRF), and total drusen volume (DV) graded on imaging by spectral-domain optical coherence tomography and using Spearman’s rank correlation test. Results DV correlated with C3b/iC3b (r = 0.285; P = 0.034), C3a (r = 0.200; P = 0.047), Ba (r = 0.262; P = 0.009), and C5 (r = 430; P = 0.005), and showed a tendency towards correlation with C3a (r = 0.198; P = 0.057). HRF correlated significantly with C5 (r = 0.388; P = 0.011) and RPD showed a tendency towards correlation with CFB (r = 0.196; P = 0.050). Conclusion In patients with early AMD, HRF and drusen parameters but not RPD show low to fair levels of correlation with local complement activation in patients’ AH. Better understanding of complement activation could provide some insights into the pathogenesis of AMD. Imaging biomarkers could be useful to identify suitable patients for future clinical trials with complement-modulating therapies.
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Wagner N, Reinehr S, Palmhof M, Schuschel D, Tsai T, Sommer E, Frank V, Stute G, Dick HB, Joachim SC. Microglia Activation in Retinal Ischemia Triggers Cytokine and Toll-Like Receptor Response. J Mol Neurosci 2021; 71:527-44. [PMID: 32833183 DOI: 10.1007/s12031-020-01674-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 07/24/2020] [Indexed: 12/20/2022]
Abstract
Mechanisms and progression of ischemic injuries in the retina are still incompletely clarified. Therefore, the time course of microglia activation as well as resulting cytokine expression and downstream signaling were investigated. Ischemia was induced in one eye by transiently elevated intraocular pressure (60 min) followed by reperfusion; the other eye served as a control. Eyes were processed for RT-qPCR and immunohistochemistry analyses at 2, 6, 12, and 24 h as well as at 3 and 7 days. Already 2 h after ischemia, more microglia/macrophages were in an active state in the ischemia group. This was accompanied by an upregulation of pro-inflammatory cytokines, like IL-1β, IL-6, TNFα, and TGFβ. Activation of TLR3, TLR2, and the adaptor molecule Myd88 was also observed after 2 h. NFκB revealed a wave-like activation pattern. In addition, an extrinsic caspase pathway activation was noted at early time points, while enhanced numbers of cleaved caspase 3+ cells could be observed in ischemic retinae throughout the study. Retinal ischemia induced an early and strong microglia/macrophage response as well as cytokine and apoptotic activation processes. Moreover, in early and late ischemic damaging processes, TLR expression and downstream signaling were involved, suggesting an involvement in neuronal death in ischemic retinae. Graphical Abstract.
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Gassel CJ, Reinehr S, Gomes SC, Dick HB, Joachim SC. Preservation of optic nerve structure by complement inhibition in experimental glaucoma. Cell Tissue Res 2020; 382:293-306. [PMID: 32676862 PMCID: PMC8285355 DOI: 10.1007/s00441-020-03240-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 06/04/2020] [Indexed: 01/09/2023]
Abstract
Glaucoma is characterized by a progressive damage of the retina and the optic nerve. Despite a huge research interest, the exact pathomechanisms are still unknown. In the experimental autoimmune glaucoma model, rats develop glaucoma-like damage of the retina and the optic nerve after immunization with an optic nerve antigen homogenate (ONA). An early activation of the complement system, even before optic nerve degeneration, was reported in this model. Here, we investigated the effects of a monoclonal antibody against complement factor C5 on optic nerves. Rats were immunized with ONA and compared to controls. In one eye of some ONA animals, the antibody against C5 was intravitreally injected (15 μmol: ONA + C5-I or 25 μmol: ONA + C5-II) before immunization and then every 2 weeks. After 6 weeks, optic nerves were processed for histology (n = 6/group). These analyses demonstrated that the intravitreal therapy reduced the depositions of the membrane attack complex compared to ONA animals (ONA + C5-I: p = 0.005; ONA + C5-II: p = 0.002). Cellular infiltration was significantly reduced in the ONA + C5-I group (p = 0.003), but not in ONA + C5-II tissues (p = 0.41). Furthermore, SMI-32 staining revealed that neurofilament was preserved in both treatment groups compared to ONA optic nerves (both p = 0.002). A decreased amount of microglia was found in treated animals in comparison to the ONA group (ONA + C5-I: p = 0.03; ONA + C5-II: p = 0.009). We observed, for the first time, that a complement system inhibition could prevent optic nerve damage in an autoimmune glaucoma model. Therefore, complement inhibition could serve as a new therapeutic tool for glaucoma.
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Affiliation(s)
- Caroline J Gassel
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Sabrina Reinehr
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Sara C Gomes
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - H Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892, Bochum, Germany.
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