Changes in complement activation products after anti-VEGF injection for choroidal neovascularization in age-related macular degeneration and pachychoroid disease

Author(s):  
Keiichiro Tanaka ◽  
Yasuharu Oguchi ◽  
Tomoko Oomori ◽  
Yumi Ishida ◽  
Hiroaki Shintake ◽  
...  

Abstract We evaluated changes in the complement system resulting from anti-vascular endothelial growth factor (VEGF) in eyes with age-related choroidal neovascularization (CNV) including neovascular age-related macular degeneration, pachychoroid neovasculopathy, and polypoidal choroidal neovasculopathy. We measured the concentrations of the complement activation products (C3a, C4a), VEGF, and monocyte chemotactic protein-1 in the aqueous humor during intravitreal anti-VEGF injections for CNV. The VEGF level decreased significantly (P < 0.001), while the C3a and C4a levels increased significantly (P < 0.001 for both comparisons) 1 month after two monthly anti-VEGF injections. The VEGF level was correlated with the C3a (R = 0.328, P = 0.007) and C4a (R = -0.237, P = 0.055) levels at baseline, but the correlation between the VEGF and C3a levels (R = -0.148, P = 0.242) changed significantly (P = 0.028 by analysis of covariance) after anti-VEGF treatment. The C3a increase after anti-VEGF therapy did not change the visual outcomes in eyes with CNV for 1 year. Dysregulation of the complement system can be induced by excessive reduction of intraocular VEGF after anti-VEGF therapy.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Keiichiro Tanaka ◽  
Yasuharu Oguchi ◽  
Tomoko Omori ◽  
Yumi Ishida ◽  
Hiroaki Shintake ◽  
...  

AbstractWe evaluated changes in the complement system resulting from anti-vascular endothelial growth factor (VEGF) in eyes with age-related choroidal neovascularization (CNV) including neovascular age-related macular degeneration, pachychoroid neovasculopathy, and polypoidal choroidal neovasculopathy. We measured the concentrations of the complement activation products (C3a, C4a), VEGF, and monocyte chemotactic protein-1 in the aqueous humor during intravitreal anti-VEGF injections for CNV. The VEGF level decreased significantly (P < 0.001), while the C3a and C4a levels increased significantly (P < 0.001 for both comparisons) 1 month after two monthly anti-VEGF injections. The VEGF level was correlated with the C3a (R = 0.328, P = 0.007) and C4a (R = − 0.237, P = 0.055) levels at baseline, but the correlation between the VEGF and C3a levels (R = − 0.148, P = 0.242) changed significantly (P = 0.028 by analysis of covariance) after anti-VEGF treatment. The C3a increase after anti-VEGF therapy did not change the visual outcomes in eyes with CNV for 1 year. Dysregulation of the complement system can be induced after anti-VEGF therapy.


The understanding of the pathogenesis of the development of choroidal neovascularization (CNV) in age-related macular degeneration (AMD) continues to evolve. Epidemiological, histopathological, and biochemical evidence indicates that neovascular AMD is associated with oxidative damage, lipofuscin accumulation, chronic inflammation, and mutation in the complement system. Molecular targets have been identified that serve as the basis for developing new, better treatments for neovascular AMD.


Author(s):  
Angela Armento ◽  
Marius Ueffing ◽  
Simon J. Clark

AbstractAge-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.


2020 ◽  
Vol 21 (24) ◽  
pp. 9752
Author(s):  
Emilie Grarup Jensen ◽  
Thomas Stax Jakobsen ◽  
Steffen Thiel ◽  
Anne Louise Askou ◽  
Thomas J. Corydon

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.


Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 635
Author(s):  
Monica L. Hu ◽  
Joel Quinn ◽  
Kanmin Xue

Age-related macular degeneration (AMD) is a multifactorial retinal disorder that is a major global cause of severe visual impairment. The development of an effective therapy to treat geographic atrophy, the predominant form of AMD, remains elusive due to the incomplete understanding of its pathogenesis. Central to AMD diagnosis and pathology are the hallmark lipid and proteinaceous deposits, drusen and reticular pseudodrusen, that accumulate in the subretinal pigment epithelium and subretinal spaces, respectively. Age-related changes and environmental stressors, such as smoking and a high-fat diet, are believed to interact with the many genetic risk variants that have been identified in several major biochemical pathways, including lipoprotein metabolism and the complement system. The APOE gene, encoding apolipoprotein E (APOE), is a major genetic risk factor for AMD, with the APOE2 allele conferring increased risk and APOE4 conferring reduced risk, in comparison to the wildtype APOE3. Paradoxically, APOE4 is the main genetic risk factor in Alzheimer's disease, a disease with features of neuroinflammation and amyloid-beta deposition in common with AMD. The potential interactions of APOE with the complement system and amyloid-beta are discussed here to shed light on their roles in AMD pathogenesis, including in drusen biogenesis, immune cell activation and recruitment, and retinal inflammation.


Nanoscale ◽  
2017 ◽  
Vol 9 (40) ◽  
pp. 15461-15469 ◽  
Author(s):  
Na-Kyung Ryoo ◽  
Jihwang Lee ◽  
Hyunjoo Lee ◽  
Hye Kyoung Hong ◽  
Hyejin Kim ◽  
...  

Age-related macular degeneration (AMD) is the leading cause of blindness in developed countries and is characterized by the development of choroidal neovascularization (CNV).


Immunobiology ◽  
2012 ◽  
Vol 217 (2) ◽  
pp. 127-146 ◽  
Author(s):  
S. Khandhadia ◽  
V. Cipriani ◽  
J.R.W. Yates ◽  
A.J. Lotery

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