1
|
Fu Y, Zhang Z, Webster KA, Paulus YM. Treatment Strategies for Anti-VEGF Resistance in Neovascular Age-Related Macular Degeneration by Targeting Arteriolar Choroidal Neovascularization. Biomolecules 2024; 14:252. [PMID: 38540673 PMCID: PMC10968528 DOI: 10.3390/biom14030252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 02/14/2024] [Accepted: 02/16/2024] [Indexed: 05/04/2024] Open
Abstract
Despite extensive use of intravitreal anti-vascular endothelial growth factor (anti-VEGF) biologics for over a decade, neovascular age-related macular degeneration (nAMD) or choroidal neovascularization (CNV) continues to be a major cause of irreversible vision loss in developed countries. Many nAMD patients demonstrate persistent disease activity or experience declining responses over time despite anti-VEGF treatment. The underlying mechanisms of anti-VEGF resistance are poorly understood, and no effective treatment strategies are available to date. Here we review evidence from animal models and clinical studies that supports the roles of neovascular remodeling and arteriolar CNV formation in anti-VEGF resistance. Cholesterol dysregulation, inflammation, and ensuing macrophage activation are critically involved in arteriolar CNV formation and anti-VEGF resistance. Combination therapy by neutralizing VEGF and enhancing cholesterol removal from macrophages is a promising strategy to combat anti-VEGF resistance in CNV.
Collapse
Affiliation(s)
- Yingbin Fu
- Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA; (Z.Z.); (K.A.W.)
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zhao Zhang
- Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA; (Z.Z.); (K.A.W.)
| | - Keith A. Webster
- Cullen Eye Institute, Baylor College of Medicine, Houston, TX 77030, USA; (Z.Z.); (K.A.W.)
- Vascular Biology Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Yannis M. Paulus
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, MI 48105, USA;
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48105, USA
| |
Collapse
|
2
|
Bonavita CM, White TM, Francis J, Farrell HE, Davis-Poynter NJ, Cardin RD. The Viral G-Protein-Coupled Receptor Homologs M33 and US28 Promote Cardiac Dysfunction during Murine Cytomegalovirus Infection. Viruses 2023; 15:711. [PMID: 36992420 PMCID: PMC10054303 DOI: 10.3390/v15030711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous pathogen that infects the majority of the world population and causes lifelong latent infection. HCMV has been shown to exacerbate cardiovascular diseases, including myocarditis, vascular sclerosis, and transplant vasculopathy. Recently, we have shown that murine CMV (MCMV) recapitulates the cardiovascular dysfunction observed in patients with HCMV-induced myocarditis. To understand the viral mechanisms involved in CMV-induced heart dysfunction, we further characterized cardiac function in response to MCMV and examined virally encoded G-protein-coupled receptor homologs (vGPCRs) US28 and M33 as potential factors that promote infection in the heart. We hypothesized that the CMV-encoded vGPCRs could exacerbate cardiovascular damage and dysfunction. Three viruses were used to evaluate the role of vGPCRs in cardiac dysfunction: wild-type MCMV, a M33-deficient virus (∆M33), and a virus with the M33 open reading frame (ORF) replaced with US28, an HCMV vGPCR (i.e., US28+). Our in vivo studies revealed that M33 plays a role in promoting cardiac dysfunction by increasing viral load and heart rate during acute infection. During latency, ΔM33-infected mice demonstrated reduced calcification, altered cellular gene expression, and less cardiac hypertrophy compared with wild-type MCMV-infected mice. Ex vivo viral reactivation from hearts was less efficient in ΔM33-infected animals. HCMV protein US28 expression restored the ability of the M33-deficient virus to reactivate from the heart. US28+ MCMV infection caused damage to the heart comparable with wild-type MCMV infection, suggesting that the US28 protein is sufficient to complement the function of M33 in the heart. Altogether, these data suggest a role for vGPCRs in viral pathogenesis in the heart and thus suggest that vGPCRs promote long-term cardiac damage and dysfunction.
Collapse
Affiliation(s)
- Cassandra M. Bonavita
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Timothy M. White
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Joseph Francis
- Department of Comparative Biological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Helen E. Farrell
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane 4072, Australia
| | | | - Rhonda D. Cardin
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| |
Collapse
|
3
|
Liu Z, Mao X, Yang Q, Zhang X, Xu J, Ma Q, Zhou Y, Da Q, Cai Y, Sopeyin A, Dong Z, Hong M, Caldwell RB, Sodhi A, Huo Y. Suppression of myeloid PFKFB3-driven glycolysis protects mice from choroidal neovascularization. Br J Pharmacol 2022; 179:5109-5131. [PMID: 35830274 DOI: 10.1111/bph.15925] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 06/09/2022] [Accepted: 07/05/2022] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND AND PURPOSE Pathological angiogenesis is a major cause of irreversible blindness in individuals with neovascular age-related macular degeneration (nAMD). Macrophages and microglia (MΦ) contribute to aberrant ocular angiogenesis. However, the role of glucose metabolism of MΦ in nAMD is still undefined. Here, we have investigated the involvement of glycolysis, driven by the kinase/phosphatase PFKFB3, in the development of choroidal neovascularization (CNV). EXPERIMENTAL APPROACH CNV was induced in mice with laser photocoagulation. Choroid/retinal pigment epithelium (RPE) complexes and MΦ were isolated for analysis by qRT-PCR, western blot, flow cytometry, immunostaining, metabolic measurements and angiogenesis assays. KEY RESULTS MΦ accumulated within the CNV of murine nAMD models and expressed high levels of glycolysis-related enzymes and M1/M2 polarization markers. This phenotype of hyper-glycolytic and activated MΦ was replicated in bone marrow-derived macrophages stimulated by necrotic RPE in vitro. Myeloid cell-specific knockout of PFKFB3, a key glycolytic activator, attenuated pathological neovascularization in laser-induced CNV, which was associated with decreased expression of MΦ polarization markers and pro-angiogenic factors, along with decreased sprouting of vessels in choroid/RPE complexes. Mechanistically, necrotic RPE increased PFKFB3-driven glycolysis in macrophages, leading to activation of HIF-1α/HIF-2α and NF-κB, and subsequent induction of M1/M2 markers and pro-angiogenic cytokines, finally promoting macrophage reprogramming towards an angiogenic phenotype to facilitate development of CNV. The PFKFB3 inhibitor AZ67 also inhibited activation of HIF-1α/HIF-2α and NF-κB signalling and almost completely prevented laser-induced CNV in mice. CONCLUSIONS AND IMPLICATIONS Modulation of PFKFB3-mediated macrophage glycolysis and activation is a promising strategy for the treatment of nAMD.
Collapse
Affiliation(s)
- Zhiping Liu
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs Research, College of Pharmacy, Jinan University, Guangzhou, China
| | - Xiaoxiao Mao
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Qiuhua Yang
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Xiaoyu Zhang
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Jiean Xu
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Qian Ma
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Yaqi Zhou
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Qingen Da
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Yongfeng Cai
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Anu Sopeyin
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia, USA
| | - Mei Hong
- State Key Laboratory of Chemical Oncogenomics, Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen, China
| | - Ruth B Caldwell
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| | - Akrit Sodhi
- Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Yuqing Huo
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
- James and Jean Culver Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia, USA
| |
Collapse
|
4
|
Blocking Autophagy in M1 Macrophages Enhances Virus Replication and Eye Disease in Ocularly Infected Transgenic Mice. J Virol 2022; 96:e0140122. [PMID: 36286481 PMCID: PMC9645210 DOI: 10.1128/jvi.01401-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Autophagy plays a critical role in clearing, disassembling, and recycling damaged cells, thus limiting inflammation. The HSV-1 γ34.5 gene is involved in neurovirulence and immune evasion by blocking autophagy in infected cells.
Collapse
|
5
|
Xu J, Liu X, Zhang X, Marshall B, Dong Z, Smith SB, Espinosa-Heidmann DG, Zhang M. Retinal and Choroidal Pathologies in Aged BALB/c Mice Following Systemic Neonatal Murine Cytomegalovirus Infection. THE AMERICAN JOURNAL OF PATHOLOGY 2021; 191:1787-1804. [PMID: 34197777 PMCID: PMC8485058 DOI: 10.1016/j.ajpath.2021.06.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 06/04/2021] [Accepted: 06/14/2021] [Indexed: 11/30/2022]
Abstract
Although pathologies associated with acute virus infections have been extensively studied, the effects of long-term latent virus infections are less well understood. Human cytomegalovirus, which infects 50% to 80% of humans, is usually acquired during early life and persists in a latent state for the lifetime. The purpose of this study was to determine whether systemic murine cytomegalovirus (MCMV) infection acquired early in life disseminates to and becomes latent in the eye and if ocular MCMV can trigger in situ inflammation and occurrence of ocular pathology. This study found that neonatal infection of BALB/c mice with MCMV resulted in dissemination of virus to the eye, where it localized principally to choroidal endothelia and pericytes and less frequently to the retinal pigment epithelium (RPE) cells. MCMV underwent ocular latency, which was associated with expression of multiple virus genes and from which MCMV could be reactivated by immunosuppression. Latent ocular infection was associated with significant up-regulation of several inflammatory/angiogenic factors. Retinal and choroidal pathologies developed in a progressive manner, with deposits appearing at both basal and apical aspects of the RPE, RPE/choroidal atrophy, photoreceptor degeneration, and neovascularization. The pathologies induced by long-term ocular MCMV latency share features of previously described human ocular diseases, such as age-related macular degeneration.
Collapse
Affiliation(s)
- Jinxian Xu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Xinglou Liu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Xinyan Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Brendan Marshall
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; Charlie Norwood Veterans Affairs Medical Center, Augusta, Georgia
| | - Sylvia B Smith
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia; Department of Ophthamology, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Diego G Espinosa-Heidmann
- James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia; Department of Ophthamology, Medical College of Georgia, Augusta University, Augusta, Georgia
| | - Ming Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, Georgia; James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, Georgia.
| |
Collapse
|
6
|
Immunological Aspects of Age-Related Macular Degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1256:143-189. [PMID: 33848001 DOI: 10.1007/978-3-030-66014-7_6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Increasing evidence over the past two decades points to a pivotal role for immune mechanisms in age-related macular degeneration (AMD) pathobiology. In this chapter, we will explore immunological aspects of AMD, with a specific focus on how immune mechanisms modulate clinical phenotypes of disease and severity and how components of the immune system may serve as triggers for disease progression in both dry and neovascular AMD. We will briefly review the biology of the immune system, defining the role of immune mechanisms in chronic degenerative disease and differentiating from immune responses to acute injury or infection. We will explore current understanding of the roles of innate immunity (especially macrophages), antigen-specific immunity (T cells, B cells, and autoimmunity), immune amplifications systems, especially complement activity and the NLRP3 inflammasome, in the pathogenesis of both dry and neovascular AMD, reviewing data from pathology, experimental animal models, and clinical studies of AMD patients. We will also assess how interactions between the immune system and infectious pathogens could potentially modulate AMD pathobiology via alterations in in immune effector mechanisms. We will conclude by reviewing the paradigm of "response to injury," which provides a means to integrate various immunologic mechanisms along with nonimmune mechanisms of tissue injury and repair as a model to understand the pathobiology of AMD.
Collapse
|
7
|
Incomplete response to Anti-VEGF therapy in neovascular AMD: Exploring disease mechanisms and therapeutic opportunities. Prog Retin Eye Res 2020; 82:100906. [PMID: 33022379 PMCID: PMC10368393 DOI: 10.1016/j.preteyeres.2020.100906] [Citation(s) in RCA: 149] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/18/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022]
Abstract
Intravitreal anti-vascular endothelial growth factor (VEGF) drugs have revolutionized the treatment of neovascular age-related macular degeneration (NVAMD). However, many patients suffer from incomplete response to anti-VEGF therapy (IRT), which is defined as (1) persistent (plasma) fluid exudation; (2) unresolved or new hemorrhage; (3) progressive lesion fibrosis; and/or (4) suboptimal vision recovery. The first three of these collectively comprise the problem of persistent disease activity (PDA) in spite of anti-VEGF therapy. Meanwhile, the problem of suboptimal vision recovery (SVR) is defined as a failure to achieve excellent functional visual acuity of 20/40 or better in spite of sufficient anti-VEGF treatment. Thus, incomplete response to anti-VEGF therapy, and specifically PDA and SVR, represent significant clinical unmet needs. In this review, we will explore PDA and SVR in NVAMD, characterizing the clinical manifestations and exploring the pathobiology of each. We will demonstrate that PDA occurs most frequently in NVAMD patients who develop high-flow CNV lesions with arteriolarization, in contrast to patients with capillary CNV who are highly responsive to anti-VEGF therapy. We will review investigations of experimental CNV and demonstrate that both types of CNV can be modeled in mice. We will present and consider a provocative hypothesis: formation of arteriolar CNV occurs via a distinct pathobiology, termed neovascular remodeling (NVR), wherein blood-derived macrophages infiltrate the incipient CNV lesion, recruit bone marrow-derived mesenchymal precursor cells (MPCs) from the circulation, and activate MPCs to become vascular smooth muscle cells (VSMCs) and myofibroblasts, driving the development of high-flow CNV with arteriolarization and perivascular fibrosis. In considering SVR, we will discuss the concept that limited or poor vision in spite of anti-VEGF may not be caused simply by photoreceptor degeneration but instead may be associated with photoreceptor synaptic dysfunction in the neurosensory retina overlying CNV, triggered by infiltrating blood-derived macrophages and mediated by Müller cell activation Finally, for each of PDA and SVR, we will discuss current approaches to disease management and treatment and consider novel avenues for potential future therapies.
Collapse
|
8
|
Xu J, Liu X, Zhang X, Marshall B, Dong Z, Liu Y, Espinosa-Heidmann DG, Zhang M. Ocular cytomegalovirus latency exacerbates the development of choroidal neovascularization. J Pathol 2020; 251:200-212. [PMID: 32243583 DOI: 10.1002/path.5447] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 02/28/2020] [Accepted: 03/27/2020] [Indexed: 12/12/2022]
Abstract
Age-related macular degeneration (AMD) is a complex, multifactorial, progressive disease which represents a leading cause of irreversible visual impairment and blindness in older individuals. Human cytomegalovirus (HCMV), which infects 50-80% of humans, is usually acquired during early life and persists in a latent state for the life of the individual. In view of its previously described pro-angiogenic properties, we hypothesized that cytomegalovirus might be a novel risk factor for progression to an advanced form, neovascular AMD, which is characterized by choroidal neovascularization (CNV). The purpose of this study was to investigate if latent ocular murine cytomegalovirus (MCMV) infection exacerbated the development of CNV in vascular endothelial growth factor (VEGF)-overexpressing VEGF-Ahyper mice. Here we show that neonatal infection with MCMV resulted in dissemination of virus to various organs throughout the body including the eye, where it localized principally to the choroid in both VEGF-overexpressingVEGF-Ahyper and wild-type(WT) 129 mice. By 6 months post-infection, no replicating virus was detected in eyes and extraocular tissues, although virus DNA was still present in all eyes and extraocular tissues of both VEGF-Ahyper and WT mice. Expression of MCMV immediate early (IE) 1 mRNA was detected only in latently infected eyes of VEGF-Ahyper mice, but not in eyes of WT mice. Significantly increased CNV was observed in eyes of MCMV-infected VEGF-Ahyper mice compared to eyes of uninfected VEGF-Ahyper mice, while no CNV lesions were observed in eyes of either infected or uninfected WT mice. Protein levels of several inflammatory/angiogenic factors, particularly VEGF and IL-6, were significantly higher in eyes of MCMV-infected VEGF-Ahyper mice, compared to uninfected controls. Initial studies of ocular tissue from human cadavers revealed that HCMV DNA was present in four choroid/retinal pigment epithelium samples from 24 cadavers. Taken together, our data suggest that ocular HCMV latency could be a significant risk factor for the development of AMD. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Collapse
Affiliation(s)
- Jinxian Xu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Xinglou Liu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA.,Department of Pediatrics, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, PR China
| | - Xinyan Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| | - Brendan Marshall
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Yutao Liu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA.,Department of Ophthalmology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Diego G Espinosa-Heidmann
- The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA.,Department of Ophthalmology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Ming Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.,The James and Jean Culver Vision Discovery Institute, Augusta University, Augusta, GA, USA
| |
Collapse
|
9
|
de Sousa JR, Da Costa Vasconcelos PF, Quaresma JAS. Functional aspects, phenotypic heterogeneity, and tissue immune response of macrophages in infectious diseases. Infect Drug Resist 2019; 12:2589-2611. [PMID: 31686866 PMCID: PMC6709804 DOI: 10.2147/idr.s208576] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 07/05/2019] [Indexed: 12/13/2022] Open
Abstract
Macrophages are a functionally heterogeneous group of cells with specialized functions depending not only on their subgroup but also on the function of the organ or tissue in which the cells are located. The concept of macrophage phenotypic heterogeneity has been investigated since the 1980s, and more recent studies have identified a diverse spectrum of phenotypic subpopulations. Several types of macrophages play a central role in the response to infectious agents and, along with other components of the immune system, determine the clinical outcome of major infectious diseases. Here, we review the functions of various macrophage phenotypic subpopulations, the concept of macrophage polarization, and the influence of these cells on the evolution of infections. In addition, we emphasize their role in the immune response in vivo and in situ, as well as the molecular effectors and signaling mechanisms used by these cells. Furthermore, we highlight the mechanisms of immune evasion triggered by infectious agents to counter the actions of macrophages and their consequences. Our aim here is to provide an overview of the role of macrophages in the pathogenesis of critical transmissible diseases and discuss how elucidation of this relationship could enhance our understanding of the host-pathogen association in organ-specific immune responses.
Collapse
Affiliation(s)
- Jorge Rodrigues de Sousa
- Tropical Medicine Center, Federal University of Pará, Belém, PA, Brazil
- Evandro Chagas Institute, Ministry of Health, Ananindeua, PA, Brazil
| | - Pedro Fernando Da Costa Vasconcelos
- Evandro Chagas Institute, Ministry of Health, Ananindeua, PA, Brazil
- Center of Biological and Health Sciences, State University of Pará, Belém, PA, Brazil
| | - Juarez Antonio Simões Quaresma
- Tropical Medicine Center, Federal University of Pará, Belém, PA, Brazil
- Evandro Chagas Institute, Ministry of Health, Ananindeua, PA, Brazil
- Center of Biological and Health Sciences, State University of Pará, Belém, PA, Brazil
- School of Medicine, São Paulo University, São Paulo, SP, Brazil
| |
Collapse
|
10
|
Murine cytomegalovirus infection in mice results in an acute inflammatory reaction in peripheral nerves. J Neuroimmunol 2019; 335:577017. [PMID: 31430710 DOI: 10.1016/j.jneuroim.2019.577017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/31/2019] [Accepted: 07/31/2019] [Indexed: 02/08/2023]
Abstract
Human cytomegalovirus (CMV) infection is asymptomatic in immunocompetent individuals. However, it can lead to disease in immunodeficient population. Little is known of the mechanisms underlying the pathogenicity of the virus. We investigated the impact of CMV infection on mouse nervous system. Peripheral nerves but not spinal cord was permissive to MCMV during acute infection. Activated CD8+ T cells, monocytes/macrophages and cytokine expression were increased in the blood and sciatic nerves of infected mice, which exhibited transient sensory dysfunction. This study indicates that systemic MCMV infection leads to a dissemination of MCMV into peripheral nerves, which is associated with a local inflammation but not nerve tissue damage in the acute phase.
Collapse
|
11
|
Faber C, Juel HB, Jensen BAH, Christensen JP, Prause JU, Thomsen AR, Nissen MH. Chemokine Expression in Murine RPE/Choroid in Response to Systemic Viral Infection and Elevated Levels of Circulating Interferon-γ. Invest Ophthalmol Vis Sci 2019; 60:192-201. [PMID: 30654385 DOI: 10.1167/iovs.18-25721] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To examine how circulating immune mediators in vivo may affect gene and protein expression at the RPE/choroid interface. Methods Young mice were systemically infected with lymphocytic choriomeningitis virus (LCMV) or continuously infused with IFN-γ. RPE/choroid was isolated and analyzed with whole-transcriptome gene expression microarrays. Selected gene expression findings were validated at the protein level. Results Both the systemic immune activation from virus infection and the sterile systemically increased level of IFN-γ resulted in increased expression of chemokine ligands, chemokine receptors, and early complement components in isolates of RPE/choroid. These findings were largely absent from LCMV-infected mice deficient in either the interferon α/β receptor or IFN-γ. Conclusions Together, these findings demonstrate that acute systemic immune activation results in a local response at the RPE/choroid interface that may include chemokine-dependent recruitment of inflammatory cells and engagement of the complement system. This may represent a link between the systemic low-grade inflammation and the retinal pathology observed in several multifactorial entities such as aging, AMD, and diabetes.
Collapse
Affiliation(s)
- Carsten Faber
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Immunology and Microbiology, Copenhagen, Denmark.,Department of Ophthalmology, Rigshospitalet-Glostrup, Glostrup, Denmark
| | - Helene Bæk Juel
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Immunology and Microbiology, Copenhagen, Denmark
| | | | - Jan Pravsgaard Christensen
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Immunology and Microbiology, Copenhagen, Denmark
| | - Jan Ulrik Prause
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Neuroscience and Pharmacology, Eye Pathology Section, Copenhagen, Denmark
| | - Allan Randrup Thomsen
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Immunology and Microbiology, Copenhagen, Denmark
| | - Mogens Holst Nissen
- University of Copenhagen, Faculty of Health and Medical Sciences, Department of Immunology and Microbiology, Copenhagen, Denmark
| |
Collapse
|
12
|
Alcendor DJ. Human Vascular Pericytes and Cytomegalovirus Pathobiology. Int J Mol Sci 2019; 20:ijms20061456. [PMID: 30909422 PMCID: PMC6471229 DOI: 10.3390/ijms20061456] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/01/2019] [Accepted: 03/20/2019] [Indexed: 12/11/2022] Open
Abstract
Pericytes are multipotent cells of the vascular system with cytoplasmic extensions proximal to endothelial cells that occur along the abluminal surface of the endothelium. The interactions between endothelial cells and pericytes are essential for proper microvascular formation, development, stabilization, and maintenance. Pericytes are essential for the regulation of paracellular flow between cells, transendothelial fluid transport, angiogenesis, and vascular immunosurveillance. They also influence the chemical composition of the surrounding microenvironment to protect endothelial cells from potential harm. Dysregulation or loss of pericyte function can result in microvascular instability and pathological consequences. Human pericytes have been shown to be targets for human cytomegalovirus (HCMV) infection and lytic replication that likely contribute to vascular inflammation. This review focuses on human vascular pericytes and their permissiveness for HCMV infection. It also discusses their implication in pathogenesis in the blood⁻brain barrier (BBB), the inner blood⁻retinal barrier (IBRB), the placenta⁻blood barrier, and the renal glomerulus as well as their potential role in subclinical vascular disease.
Collapse
Affiliation(s)
- Donald J Alcendor
- Center for AIDS Health Disparities Research, Department of Microbiology, Immunology, and Physiology, School of Medicine, Meharry Medical College, 1005 Dr. D.B. Todd Jr. Blvd., Hubbard Hospital, 5th Floor, Rm. 5025, Nashville, TN 37208, USA.
| |
Collapse
|
13
|
Suppressor of Cytokine Signaling 1 (SOCS1) and SOCS3 Are Stimulated within the Eye during Experimental Murine Cytomegalovirus Retinitis in Mice with Retrovirus-Induced Immunosuppression. J Virol 2018; 92:JVI.00526-18. [PMID: 29976680 DOI: 10.1128/jvi.00526-18] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 06/15/2018] [Indexed: 11/20/2022] Open
Abstract
AIDS-related human cytomegalovirus retinitis remains the leading cause of blindness among untreated HIV/AIDS patients worldwide. To study mechanisms of this disease, we used a clinically relevant animal model of murine cytomegalovirus (MCMV) retinitis with retrovirus-induced murine AIDS (MAIDS) that mimics the progression of AIDS in humans. We found in this model that MCMV infection significantly stimulates ocular suppressor of cytokine signaling 1 (SOCS1) and SOCS3, host proteins which hinder immune-related signaling by cytokines, including antiviral type I and type II interferons. The present study demonstrates that in the absence of retinal disease, systemic MCMV infection of mice without MAIDS, but not in mice with MAIDS, leads to mild stimulation of splenic SOCS1 mRNA. In sharp contrast, when MCMV is directly inoculated into the eyes of retinitis-susceptible MAIDS mice, high levels of intraocular SOCS1 and SOCS3 mRNA and protein are produced which are associated with significant intraocular upregulation of gamma interferon (IFN-γ) and interleukin-6 (IL-6) mRNA expression. We also show that infiltrating macrophages, granulocytes, and resident retinal cells are sources of intraocular SOCS1 and SOCS3 protein production during development of MAIDS-related MCMV retinitis, and SOCS1 and SOCS3 mRNA transcripts are detected in retinal areas histologically characteristic of MCMV retinitis. Furthermore, SOCS1 and SOCS3 are found in both MCMV-infected cells and uninfected cells, suggesting that these SOCS proteins are stimulated via a bystander mechanism during MCMV retinitis. Taken together, our findings suggest a role for MCMV-related stimulation of SOCS1 and SOCS3 in the progression of retinal disease during ocular, but not systemic, MCMV infection.IMPORTANCE Cytomegalovirus infection frequently causes blindness in untreated HIV/AIDS patients. This virus manipulates host cells to dysregulate immune functions and drive disease. Here, we use an animal model of this disease to demonstrate that cytomegalovirus infection within eyes during retinitis causes massive upregulation of immunosuppressive host proteins called SOCS. As viral overexpression of SOCS proteins exacerbates infection with other viruses, they may also enhance cytomegalovirus infection. Alternatively, the immunosuppressive effect of SOCS proteins may be protective against immunopathology during cytomegalovirus retinitis, and in such a case SOCS mimetics or overexpression treatment strategies might be used to combat this disease. The results of this work therefore provide crucial basic knowledge that contributes to our understanding of the mechanisms of AIDS-related cytomegalovirus retinitis and, together with future studies, may contribute to the development of novel therapeutic targets that could improve the treatment or management of this sight-threatening disease.
Collapse
|
14
|
Xu J, Liu X, Mo J, Marshall B, Perry L, Dong Z, Zhang M. Inflammation and outer blood-retina barrier (BRB) compromise following choroidal murine cytomegalovirus (MCMV) infections. Mol Vis 2018; 24:379-394. [PMID: 29853772 PMCID: PMC5957546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 05/16/2018] [Indexed: 11/25/2022] Open
Abstract
PURPOSE The purpose of this study was to determine whether the blood-retina barrier is compromised by choroidal murine cytomegalovirus (MCMV) infection, using electron microscopy. METHODS BALB/c mice were immunosuppressed with methylprednisolone and monoclonal antibodies to CD4 and CD8. At several time points post-MCMV intraperitoneal inoculation, the eyes were removed and analyzed with western blotting and immunoelectron microscopy for the presence of MCMV early antigen (EA) and the host protein RIP3. Posterior eyecups from RIP3-/- and RIP3+/+ mice were cultured and inoculated with MCMV. At days 4, 7, and 11 post-infection, cultures were collected and analyzed with plaque assay, immunohistochemical staining, and real-time PCR (RT-PCR). RESULTS MCMV EA was observed in the nuclei of vascular endothelial cells and pericytes in the choriocapillaris. Disruption of Bruch's membrane was observed, especially at sites adjacent to activated platelets, and a few RPE cells containing some enlarged vesicles were found directly beneath disrupted Bruch's membrane. Some virus particles were also observed in the enlarged vesicles of RPE cells. Levels of the RIP3 protein, which was observed mainly in the RPE cells and the basement membrane of the choriocapillaris, were greatly increased following MCMV infection, while depletion of RIP3 resulted in greatly decreased inflammasome formation, as well as expression of downstream inflammation factors. CONCLUSIONS The results suggest that systemic MCMV spreads to the choroid and replicates in vascular endothelia and pericytes of the choriocapillaris during immunosuppression. Choroidal MCMV infection is associated with in situ inflammation and subsequent disruption of Bruch's membrane and the outer blood-retina barrier.
Collapse
Affiliation(s)
- Jinxian Xu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA,James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA
| | - Xinglou Liu
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA,James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA
| | - Juan Mo
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA
| | - Brendan Marshall
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA
| | - Libby Perry
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA
| | - Zheng Dong
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA,Charlie Norwood VA Medical Center, Augusta, GA
| | - Ming Zhang
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA,James and Jean Vision Discovery Institute, Medical College of Georgia, Augusta University, Augusta, GA
| |
Collapse
|
15
|
Modrzejewska M, Kulik U, Modrzejewska A. Nosocomial Cytomegalovirus Infection Resulting in Worsening of Retinopathy of Prematurity. Indian J Pediatr 2018; 85:401-402. [PMID: 29127613 DOI: 10.1007/s12098-017-2507-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Accepted: 09/20/2017] [Indexed: 10/18/2022]
Affiliation(s)
- Monika Modrzejewska
- Department of Ophthalmology, Pomeranian Medical University, Powst. Wlp. str., 72, 70-111, Szczecin, Poland.
| | - Urszula Kulik
- Department of Ophthalmology, Pomeranian Medical University, Powst. Wlp. str., 72, 70-111, Szczecin, Poland
| | - Anna Modrzejewska
- Department of Ophthalmology, Pomeranian Medical University, Powst. Wlp. str., 72, 70-111, Szczecin, Poland
| |
Collapse
|
16
|
Feng L, Ju M, Lee KYV, Mackey A, Evangelista M, Iwata D, Adamson P, Lashkari K, Foxton R, Shima D, Ng YS. A Proinflammatory Function of Toll-Like Receptor 2 in the Retinal Pigment Epithelium as a Novel Target for Reducing Choroidal Neovascularization in Age-Related Macular Degeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:2208-2221. [PMID: 28739342 DOI: 10.1016/j.ajpath.2017.06.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/16/2017] [Accepted: 06/08/2017] [Indexed: 11/28/2022]
Abstract
Current treatments for choroidal neovascularization, a major cause of blindness for patients with age-related macular degeneration, treat symptoms but not the underlying causes of the disease. Inflammation has been strongly implicated in the pathogenesis of choroidal neovascularization. We examined the inflammatory role of Toll-like receptor 2 (TLR2) in age-related macular degeneration. TLR2 was robustly expressed by the retinal pigment epithelium in mouse and human eyes, both normal and with macular degeneration/choroidal neovascularization. Nuclear localization of NF-κB, a major downstream target of TLR2 signaling, was detected in the retinal pigment epithelium of human eyes, particularly in eyes with advanced stages of age-related macular degeneration. TLR2 antagonism effectively suppressed initiation and growth of spontaneous choroidal neovascularization in a mouse model, and the combination of anti-TLR2 and antivascular endothelial growth factor receptor 2 yielded an additive therapeutic effect on both area and number of spontaneous choroidal neovascularization lesions. Finally, in primary human fetal retinal pigment epithelium cells, ligand binding to TLR2 induced robust expression of proinflammatory cytokines, and end products of lipid oxidation had a synergistic effect on TLR2 activation. Our data illustrate a functional role for TLR2 in the pathogenesis of choroidal neovascularization, likely by promoting inflammation of the retinal pigment epithelium, and validate TLR2 as a novel therapeutic target for reducing choroidal neovascularization.
Collapse
Affiliation(s)
- Lili Feng
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Meihua Ju
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Kei Ying V Lee
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Ashley Mackey
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Mariasilvia Evangelista
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Daiju Iwata
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Peter Adamson
- University College of London Institute of Ophthalmology, London, United Kingdom
| | - Kameran Lashkari
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts
| | - Richard Foxton
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - David Shima
- University College of London Institute of Ophthalmology, London, United Kingdom; Department of Ocular Biology and Therapeutics, University College of London Institute of Ophthalmology, London, United Kingdom
| | - Yin Shan Ng
- Department of Ophthalmology, Schepens Eye Research Institute of Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts.
| |
Collapse
|
17
|
Erkes DA, Wilski NA, Snyder CM. Intratumoral infection by CMV may change the tumor environment by directly interacting with tumor-associated macrophages to promote cancer immunity. Hum Vaccin Immunother 2017; 13:1778-1785. [PMID: 28604162 DOI: 10.1080/21645515.2017.1331795] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cytomegalovirus (CMV) is a herpesvirus that induces an extremely robust and sustained immune response. For this reason, CMV has been proposed as a vaccine vector to promote immunity to both pathogens and cancer. However, exploration of CMV as a vaccine vector is at an early stage and there are many questions. Using a mouse melanoma model, we recently found that a CMV-based vaccine induced large populations of melanoma-specific T cells, but was not effective at slowing tumor growth unless it was injected directly into the tumor. These surprising results have led us to hypothesize that CMV may be adept at modulating the tumor micro-environment through its infection of macrophages. Importantly, injection of CMV into the growing tumor synergized with blockade of the PD-1 checkpoint to clear well-established tumors. Here, we discuss our results in the context of CMV-based vaccines for pathogens and cancer.
Collapse
Affiliation(s)
- Dan A Erkes
- a Department of Microbiology and Immunology, Sidney Kimmel Cancer Center , Thomas Jefferson University , Philadelphia , PA , USA
| | - Nicole A Wilski
- a Department of Microbiology and Immunology, Sidney Kimmel Cancer Center , Thomas Jefferson University , Philadelphia , PA , USA
| | - Christopher M Snyder
- a Department of Microbiology and Immunology, Sidney Kimmel Cancer Center , Thomas Jefferson University , Philadelphia , PA , USA
| |
Collapse
|
18
|
Alston CI, Dix RD. Murine cytomegalovirus infection of mouse macrophages stimulates early expression of suppressor of cytokine signaling (SOCS)1 and SOCS3. PLoS One 2017; 12:e0171812. [PMID: 28182772 PMCID: PMC5300177 DOI: 10.1371/journal.pone.0171812] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 01/26/2017] [Indexed: 12/13/2022] Open
Abstract
Human cytomegalovirus (HCMV) is a species-specific β-herpesvirus that infects for life up to 80% of the world’s population and causes severe morbidity in at-risk immunocompromised populations. Suppressors of cytokine signaling (SOCS)1 and SOCS3 are host proteins that act as inducible negative feedback regulators of cytokine signaling and have been implicated in several ocular diseases and viral infections. We recently found in our mouse model of experimental cytomegalovirus retinitis that subretinally-injected murine cytomegalovirus (MCMV) stimulates ocular SOCS1 and SOCS3 during retrovirus-induced immune suppression of murine AIDS (MAIDS), and that infiltrating macrophages are prominent cellular sources of retinal SOCS1 and SOCS3 expression. Herein we investigate possible virologic mechanisms whereby MCMV infection may stimulate SOCS1 and/or SOCS3 expression in cell culture. We report that infection of IC-21 mouse macrophages with MCMV propagated through the salivary glands of BALB/c mice, but not from tissue culture in C57BL/6 fibroblasts, transiently stimulates SOCS1 and SOCS3 mRNA transcripts, but not SOCS5 mRNA. Viral tegument proteins are insufficient for this stimulation, as replication-deficient UV-inactivated MCMV fails to stimulate SOCS1 or SOCS3 in IC-21 macrophages. By contrast, infection of murine embryonic fibroblasts (MEFs) with either productive MCMV or UV-inactivated MCMV significantly stimulates SOCS1 and SOCS3 mRNA expression early after infection. Treatment of MCMV-infected IC-21 mouse macrophages with the antiviral drug ganciclovir significantly decreases MCMV-stimulated SOCS3 expression at 3 days post-infection. These data suggest cell type-specific, different roles for viral immediate early or early gene expression and/or viral tegument proteins in the early stimulation of SOCS1 and SOCS3 during MCMV infection. Furthermore, putative biphasic stimulation of SOCS3 during late MCMV infection of IC-21 mouse macrophages may occur by divergent virologic mechanisms.
Collapse
Affiliation(s)
- Christine I. Alston
- Viral Immunology Center, Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Richard D. Dix
- Viral Immunology Center, Department of Biology, Georgia State University, Atlanta, Georgia, United States of America
- Department of Ophthalmology, Emory University School of Medicine, Atlanta, Georgia, United States of America
- * E-mail:
| |
Collapse
|
19
|
Gene expression regulation in retinal pigment epithelial cells induced by viral RNA and viral/bacterial DNA. Mol Vis 2015; 21:1000-16. [PMID: 26330750 PMCID: PMC4554413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 08/29/2015] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The pathogenesis of age-related macular degeneration (AMD) is associated with systemic and local inflammation. Various studies suggested that viral or bacterial infection may aggravate retinal inflammation in the aged retina. We compared the effects of synthetic viral RNA (poly(I:C)) and viral/bacterial DNA (CpG-ODN) on the expression of genes known to be involved in the development of AMD in retinal pigment epithelial (RPE) cells. METHODS Cultured human RPE cells were stimulated with poly(I:C; 500 µg/ml) or CpG-ODN (500 nM). Alterations in gene expression and protein secretion were determined with real-time RT-PCR and ELISA, respectively. Phosphorylation of signal transduction molecules was revealed by western blotting. RESULTS Poly(I:C) induced gene expression of the pattern recognition receptor TLR3, transcription factors (HIF-1α, p65/NF-κB), the angiogenic factor bFGF, inflammatory factors (IL-1β, IL-6, TNFα, MCP-1, MIP-2), and complement factors (C5, C9, CFB). Poly(I:C) also induced phosphorylation of ERK1/2 and p38 MAPK proteins, and the secretion of bFGF and TNFα from the cells. CpG-ODN induced moderate gene expression of transcription factors (p65/NF-κB, NFAT5) and complement factors (C5, C9), while it had no effect on the expression of various TLR, angiogenic factor, and inflammatory factor genes. The activities of various signal transduction pathways and transcription factors were differentially involved in mediating the poly(I:C)-induced transcriptional activation of distinct genes. CONCLUSIONS The widespread effects of viral RNA, and the restricted effects of viral/bacterial DNA, on the gene expression pattern of RPE cells may suggest that viral RNA rather than viral/bacterial DNA induces physiologic alterations of RPE cells, which may aggravate inflammation in the aged retina. The data also suggest that selective inhibition of distinct signal transduction pathways or individual transcription factors may not be effective to inhibit viral retinal inflammation.
Collapse
|
20
|
Amemiya K, Dankmeyer JL, Fetterer DP, Worsham PL, Welkos SL, Cote CK. Comparison of the early host immune response to two widely diverse virulent strains of Burkholderia pseudomallei that cause acute or chronic infections in BALB/c mice. Microb Pathog 2015; 86:53-63. [PMID: 26162294 DOI: 10.1016/j.micpath.2015.07.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 06/30/2015] [Accepted: 07/02/2015] [Indexed: 10/23/2022]
Abstract
Burkholderia pseudomallei is the etiologic agent of melioidosis, which is endemic in Southeast Asia and Northern Australia. We previously found by the intraperitoneal (IP) route that we could discern differences in virulence in mice amongst different strains of B. pseudomallei. We report an early immune response study comparing two strains in our collection which represent the least, B. pseudomallei 1106a, and one of the most, HBPUB10134a, virulent strains in BALB/c mice. B. pseudomallei HBPUB10134a infected mouse spleens contained a 2-3 log higher bacterial burden than mice infected with B. pseudomallei 1106a 3 days post-infection (PI). More and higher amounts of inflammatory cytokines/chemokines were detected in sera and spleen extracts from B. pseudomallei HBPUB10134a than B. pseudomallei 1106a infected mice. The most prominent were IFNγ, IL-1α, IL-1β, IL-6, IL-10, IP-10, and MIG. After 7 days PI, there was a decrease in bacterial burden in spleens from 1106a infected mice and a decrease in cytokines/chemokines in sera and spleen extracts from both sets of mice. By day 14 PI we saw an increase in monocytes/macrophages, NK cells, and granulocytes in spleens from both sets of mice. No B. pseudomallei HBPUB10134a infected mice survived after this time. In summary, B. pseudomallei HBPUB10134a was more virulent and induced host innate immune responses typical of a more acute-type infection than did B. pseudomallei 1106a which produced a more chronic infection in mice.
Collapse
Affiliation(s)
- Kei Amemiya
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA.
| | - Jennifer L Dankmeyer
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - David P Fetterer
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Patricia L Worsham
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Susan L Welkos
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| | - Christopher K Cote
- United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Bacteriology Division, 1425 Porter Street, Fort Detrick, Frederick, MD 21702, USA
| |
Collapse
|
21
|
Fischer T. [The age-related macular degeneration as a vascular disease/part of systemic vasculopathy: contributions to its pathogenesis]. Orv Hetil 2015; 156:358-65. [PMID: 25702256 DOI: 10.1556/oh.2015.30017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The wall of blood vessels including those in choroids may be harmed by several repeated and/or prolonged mechanical, physical, chemical, microbiological, immunologic, and genetic impacts (risk factors), which may trigger a protracted response, the so-called host defense response. As a consequence, pathological changes resulting in vascular injury (e. g. atherosclerosis, age-related macular degeneration) may be evolved. Risk factors can also act directly on the endothelium through an increased production of reactive oxygen species promoting an endothelial activation, which leads to endothelial dysfunction, the onset of vascular disease. Thus, endothelial dysfunction is a link between the harmful stimulus and vascular injury; any kind of harmful stimuli may trigger the defensive chain that results in inflammation that may lead to vascular injury. It has been shown that even early age-related macular degeneration is associated with the presence of diffuse arterial disease and patients with early age-related macular degeneration demonstrate signs of systemic and retinal vascular alterations. Chronic inflammation, a feature of AMD, is tightly linked to diseases associated with ED: AMD is accompanied by a general inflammatory response, in the form of complement system activation, similar to that observed in degenerative vascular diseases such as atherosclerosis. All these facts indicate that age-related macular degeneration may be a vascular disease (or part of a systemic vasculopathy). This recognition could have therapeutic implications because restoration of endothelial dysfunction may prevent the development or improve vascular disease resulting in prevention or improvement of age-related macular degeneration as well.
Collapse
|
22
|
Grunin M, Hagbi-Levi S, Chowers I. The role of monocytes and macrophages in age-related macular degeneration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 801:199-205. [PMID: 24664699 DOI: 10.1007/978-1-4614-3209-8_26] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
White blood cells, particularly monocytes and their descendants, macrophages, have been implicated in age-related macular degeneration (AMD) pathology. In this minireview, we describe the current knowledge of monocyte and macrophage involvement in AMD. Chemokine receptors present on these cells such as CCR1, CCR2, and CX3CR1, and their roles in monocyte/macrophage recruitment to sites of injury and inflammation in the context of AMD will be reviewed. Mice models for perturbation of chemokine receptors that recapitulate some of the features of AMD are also described. The body of evidence from human and rodent studies at this point in time suggests that monocyte and macrophages may modulate the course of AMD.
Collapse
Affiliation(s)
- Michelle Grunin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, 91120, Jerusalem, Israel,
| | | | | |
Collapse
|
23
|
Campochiaro PA. Ocular neovascularization. J Mol Med (Berl) 2013; 91:311-21. [PMID: 23329331 DOI: 10.1007/s00109-013-0993-5] [Citation(s) in RCA: 282] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 12/22/2012] [Accepted: 01/02/2013] [Indexed: 01/18/2023]
Abstract
Retinal and choroidal vascular diseases constitute the most common causes of moderate and severe vision loss in developed countries. They can be divided into retinal vascular diseases, in which there is leakage and/or neovascularization (NV) from retinal vessels, and subretinal NV, in which new vessels grow into the normally avascular outer retina and subretinal space. The first category of diseases includes diabetic retinopathy, retinal vein occlusions, and retinopathy of prematurity, and the second category includes neovascular age-related macular degeneration (AMD), ocular histoplasmosis, pathologic myopia, and other related diseases. Retinal hypoxia is a key feature of the first category of diseases resulting in elevated levels of hypoxia-inducible factor-1 (HIF-1) which stimulates expression of vascular endothelial growth factor (VEGF), platelet-derived growth factor-B (PDGF-B), placental growth factor, stromal-derived growth factor-1 and their receptors, as well as other hypoxia-regulated gene products such as angiopoietin-2. Although hypoxia has not been demonstrated as part of the second category of diseases, HIF-1 is elevated and thus the same group of hypoxia-regulated gene products plays a role. Clinical trials have shown that VEGF antagonists provide major benefits for patients with subretinal NV due to AMD and even greater benefits are seen by combining antagonists of VEGF and PDGF-B. It is likely that addition of antagonists of other agents listed above will be tested in the future. Other appealing strategies are to directly target HIF-1 or to use gene transfer to express endogenous or engineered anti-angiogenic proteins. While substantial progress has been made, the future looks even brighter for patients with retinal and choroidal vascular diseases.
Collapse
Affiliation(s)
- Peter A Campochiaro
- Departments of Ophthalmology and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21287-9277, USA.
| |
Collapse
|
24
|
Jiang K, Cao S, Cui JZ, Matsubara JA. Immuno-modulatory Effect of IFN-gamma in AMD and its Role as a Possible Target for Therapy. ACTA ACUST UNITED AC 2011; Suppl 2:0071-76. [PMID: 24977104 PMCID: PMC4071053 DOI: 10.4172/2155-9570-s2-007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Age-related macular degeneration (AMD) is a neurodegenerative disease characterized by retinal cell atrophy, and/or choroidal neovascularization in the macula and constitutes the most common cause of blindness among the elderly in industrialized countries. The management of AMD is constrained by our insufficient knowledge of its underlying mechanisms. Recent studies point towards an emerging involvement of interferon-gamma (IFN-γ), a soluble cytokine associated with innate and adaptive immunity. IFN-γ promotes proinflammatory responses by activating proinflammatory cytokines and chemokines, thereby recruiting immune cells such as macrophages and T cells. On the other hand, IFN-γ modulates inflammatory response by upregulating anti-inflammatory factors or inhibiting development of immune cells related to autoimmune response. The complex role of IFN-γ in AMD pathogenesis is intriguing and worth further investigation in terms of therapeutic development.
Collapse
Affiliation(s)
- Kailun Jiang
- Department of Ophthalmology and Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Canada
| | - Sijia Cao
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver BC, Canada
| | - Jing Z Cui
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver BC, Canada
| | - Joanne A Matsubara
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver BC, Canada
| |
Collapse
|