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Moradi K, Mitew S, Xing YL, Merson TD. HB-EGF and EGF infusion following CNS demyelination mitigates age-related decline in regeneration of oligodendrocytes from neural precursor cells originating in the ventricular-subventricular zone. bioRxiv 2024:2024.02.26.582092. [PMID: 38529498 PMCID: PMC10962700 DOI: 10.1101/2024.02.26.582092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
In multiple sclerosis (MS), chronic demyelination initiated by immune-mediated destruction of myelin, leads to axonal damage and neuronal cell death, resulting in a progressive decline in neurological function. The development of interventions that potentiate remyelination could hold promise as a novel treatment strategy for MS. To this end, our group has demonstrated that neural precursor cells (NPCs) residing in the ventricular-subventricular zone (V-SVZ) of the adult mouse brain contribute significantly to remyelination in response to central nervous system (CNS) demyelination and can regenerate myelin of normal thickness. However, aging takes its toll on the regenerative potential of NPCs and reduces their contribution to remyelination. In this study, we investigated how aging influences the contribution of NPCs to oligodendrogenesis during the remyelination process and whether the delivery of growth factors into the brains of aged mice could potentiate the oligodendrogenic potential of NPCs. To enable us to map the fate of NPCs in response to demyelination induced at different postnatal ages, Nestin-CreERT2;Rosa26-LSL-eYFP mice were gavaged with tamoxifen at either 8 weeks, 30 weeks or one year of age before being challenged with cuprizone for a period of six weeks. Using osmotic minipumps, we infused heparin-binding EGF-like growth factor (HB-EGF), and/or epidermal growth factor (EGF) into the cisterna magna for a period of two weeks beginning at the peak of cuprizone-induced demyelination (n=6-8 mice per group). Control mice received artificial cerebrospinal fluid (vehicle) alone. Mice were perfused six weeks after cuprizone withdrawal and the contribution of NPCs to oligodendrocyte regeneration in the corpus callosum was assessed. Our data reveal that although NPC-derived oligodendrocyte generation declined dramatically with age, this decline was partially reversed by growth factor infusion. Notably, co-infusion of EGF and HB-EGF increased oligodendrocyte regeneration twofold in some regions of the corpus callosum. Our results shed light on the beneficial effects of EGF and HB-EGF for increasing the contribution of NPCs to remyelination and indicate their therapeutic potential to combat the negative effects of aging upon remyelination efficacy.
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Affiliation(s)
- Kaveh Moradi
- Australian Regenerative Medicine Institute, 15 Innovation Walk, Monash University, Clayton, Victoria, Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia
| | - Stanislaw Mitew
- Australian Regenerative Medicine Institute, 15 Innovation Walk, Monash University, Clayton, Victoria, Australia
| | - Yao Lulu Xing
- Australian Regenerative Medicine Institute, 15 Innovation Walk, Monash University, Clayton, Victoria, Australia
| | - Tobias D. Merson
- Australian Regenerative Medicine Institute, 15 Innovation Walk, Monash University, Clayton, Victoria, Australia
- Current address: Oligodendroglial Interactions Group, National Institute of Mental Health, National Institutes of Health, Bethesda, USA
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2
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Xing YL, Poh J, Chuang BH, Moradi K, Mitew S, Richardson WD, Kilpatrick TJ, Osanai Y, Merson TD. High-efficiency pharmacogenetic ablation of oligodendrocyte progenitor cells in the adult mouse CNS. Cell Rep Methods 2023; 3:100414. [PMID: 36936074 PMCID: PMC10014347 DOI: 10.1016/j.crmeth.2023.100414] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 10/11/2022] [Accepted: 01/30/2023] [Indexed: 03/02/2023]
Abstract
Approaches to investigate adult oligodendrocyte progenitor cells (OPCs) by targeted cell ablation in the rodent CNS have limitations in the extent and duration of OPC depletion. We have developed a pharmacogenetic approach for conditional OPC ablation, eliminating >98% of OPCs throughout the brain. By combining recombinase-based transgenic and viral strategies for targeting OPCs and ventricular-subventricular zone (V-SVZ)-derived neural precursor cells (NPCs), we found that new PDGFRA-expressing cells born in the V-SVZ repopulated the OPC-deficient brain starting 12 days after OPC ablation. Our data reveal that OPC depletion induces V-SVZ-derived NPCs to generate vast numbers of PDGFRA+NG2+ cells with the capacity to proliferate and migrate extensively throughout the dorsal anterior forebrain. Further application of this approach to ablate OPCs will advance knowledge of the function of both OPCs and oligodendrogenic NPCs in health and disease.
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Affiliation(s)
- Yao Lulu Xing
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Jasmine Poh
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Bernard H.A. Chuang
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Kaveh Moradi
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC 3052, Australia
| | - Stanislaw Mitew
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - William D. Richardson
- Wolfson Institute for Biomedical Research, University College London, London WC1E 6BT, UK
| | - Trevor J. Kilpatrick
- Florey Institute of Neuroscience and Mental Health, Parkville, VIC 3052, Australia
- Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3052, Australia
| | - Yasuyuki Osanai
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
| | - Tobias D. Merson
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia
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Huang J, U KP, Yang F, Ji Z, Lin J, Weng Z, Tsang LL, Merson TD, Ruan YC, Wan C, Li G, Jiang X. Human pluripotent stem cell-derived ectomesenchymal stromal cells promote more robust functional recovery than umbilical cord-derived mesenchymal stromal cells after hypoxic-ischaemic brain damage. Am J Cancer Res 2022; 12:143-166. [PMID: 34987639 PMCID: PMC8690936 DOI: 10.7150/thno.57234] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [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: 12/17/2020] [Accepted: 08/06/2021] [Indexed: 02/07/2023] Open
Abstract
Aims: Hypoxic-ischaemic encephalopathy (HIE) is one of the most serious complications in neonates and infants. Mesenchymal stromal cell (MSC)-based therapy is emerging as a promising treatment avenue for HIE. However, despite its enormous potential, the clinical application of MSCs is limited by cell heterogeneity, low isolation efficiency and unpredictable effectiveness. In this study, we examined the therapeutic effects and underlying mechanisms of human pluripotent stem cell-derived ectomesenchymal stromal cells (hPSC-EMSCs) in a rat model of HIE. Methods: hPSC-EMSCs were induced from either human embryonic stem cells or induced pluripotent stem cells. Stem cells or the conditioned medium (CM) derived from stem cells were delivered intracranially or intranasally to neonatal rats with HIE. Human umbilical cord-derived MSCs (hUC-MSCs) were used as the therapeutic comparison control and phosphate-buffered saline (PBS) was used as a negative control. Lesion size, apoptosis, neurogenesis, astrogliosis and microgliosis were evaluated. The rotarod test and Morris water maze were used to determine brain functional recovery. The PC-12 cell line, rat primary cortical neurons and neural progenitor cells were used to evaluate neurite outgrowth and the neuroprotective and neurogenesis effects of hPSC-EMSCs/hUC-MSCs. RNA-seq and enzyme-linked immunosorbent assays were used to determine the secretory factors that were differentially expressed between hPSC-EMSCs and hUC-MSCs. The activation and suppression of extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB) were characterised using western blotting and immunofluorescent staining. Results: hPSC-EMSCs showed a higher neuroprotective potential than hUC-MSCs, as demonstrated by a more significant reduction in lesion size and apoptosis in the rat brain following hypoxia-ischaemia (HI). Compared with PBS treatment, hPSC-EMSCs promoted endogenous neurogenesis and alleviated astrogliosis and microgliosis. hPSC-EMSCs were more effective than hUC-MSCs. hPSC-EMSCs achieved a greater recovery of brain function than hUC-MSCs and PBS in rats with HIE. CM derived from hPSC-EMSCs had neuroprotective and neurorestorative effects in vitro through anti-apoptotic and neurite outgrowth- and neurogenesis-promoting effects. Direct comparisons between hPSC-EMSCs and hUC-MSCs revealed the significant enrichment of a group of secretory factors in hPSC-EMSCs, including nerve growth factor (NGF), platelet-derived growth factor-AA and transforming growth factor-β2, which are involved in neurogenesis, synaptic transmission and neurotransmitter transport, respectively. Mechanistically, the CM derived from hPSC-EMSCs was found to potentiate NGF-induced neurite outgrowth and the neuronal differentiation of NPCs via the ERK/CREB pathway. Suppression of ERK or CREB abolished CM-potentiated neuritogenesis and neuronal differentiation. Finally, intranasal delivery of the CM derived from hPSC-EMSCs significantly reduced brain lesion size, promoted endogenous neurogenesis, mitigated inflammatory responses and improved functional recovery in rats with HIE. Conclusion: hPSC-EMSCs promote functional recovery after HI through multifaceted neuromodulatory activities via paracrine/trophic mechanisms. We propose the use of hPSC-EMSCs for the treatment of HIE, as they offer an excellent unlimited cellular source of MSCs.
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Motamed S, Del Borgo MP, Zhou K, Kulkarni K, Crack PJ, Merson TD, Aguilar MI, Finkelstein DI, Forsythe JS. Migration and Differentiation of Neural Stem Cells Diverted From the Subventricular Zone by an Injectable Self-Assembling β-Peptide Hydrogel. Front Bioeng Biotechnol 2019; 7:315. [PMID: 31788470 PMCID: PMC6856563 DOI: 10.3389/fbioe.2019.00315] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [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: 02/03/2019] [Accepted: 10/24/2019] [Indexed: 11/13/2022] Open
Abstract
Neural stem cells, which are confined in localised niches are unable to repair large brain lesions because of an inability to migrate long distances and engraft. To overcome these problems, previous research has demonstrated the use of biomaterial implants to redirect increased numbers of endogenous neural stem cell populations. However, the fate of the diverted neural stem cells and their progeny remains unknown. Here we show that neural stem cells originating from the subventricular zone can migrate to the cortex with the aid of a long-lasting injectable hydrogel within a mouse brain. Specifically, large numbers of neuroblasts were diverted to the cortex through a self-assembling β-peptide hydrogel that acted as a tract from the subventricular zone to the cortex of transgenic mice (NestinCreERT2:R26eYFP) in which neuroblasts and their progeny are permanently fluorescently labelled. Moreover, neuroblasts differentiated into neurons and astrocytes 35 days post implantation, and the neuroblast-derived neurons were Syn1 positive suggesting integration into existing neural circuitry. In addition, astrocytes co-localised with neuroblasts along the hydrogel tract, suggesting that they assisted migration and simulated pathways similar to the native rostral migratory stream. Lower levels of astrocytes were found at the boundary of hydrogels with encapsulated brain-derived neurotrophic factor, comparing with hydrogel implants alone.
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Affiliation(s)
- Sepideh Motamed
- Department of Materials Science and Engineering, Monash Institute of Medical Engineering, Monash University, Clayton, VIC, Australia.,Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Mark P Del Borgo
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Kun Zhou
- Department of Materials Science and Engineering, Monash Institute of Medical Engineering, Monash University, Clayton, VIC, Australia
| | - Ketav Kulkarni
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Peter J Crack
- Department of Pharmacology, The University of Melbourne, Parkville, VIC, Australia
| | - Tobias D Merson
- Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, Australia
| | - Marie-Isabel Aguilar
- Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - David I Finkelstein
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - John S Forsythe
- Department of Materials Science and Engineering, Monash Institute of Medical Engineering, Monash University, Clayton, VIC, Australia
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5
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Truong PH, Ciccotosto GD, Merson TD, Spoerri L, Chuei MJ, Ayers M, Xing YL, Emery B, Cappai R. Amyloid precursor protein and amyloid precursor-like protein 2 have distinct roles in modulating myelination, demyelination, and remyelination of axons. Glia 2018; 67:525-538. [DOI: 10.1002/glia.23561] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 12/14/2022]
Affiliation(s)
- Phan H. Truong
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
- The Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Melbourne Victoria Australia
- Department of Pharmacology and Therapeutics; The University of Melbourne; Melbourne Victoria Australia
| | - Giuseppe D. Ciccotosto
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
- The Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Melbourne Victoria Australia
- Department of Pharmacology and Therapeutics; The University of Melbourne; Melbourne Victoria Australia
| | - Tobias D. Merson
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne Victoria Australia
| | - Loredana Spoerri
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
- The Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Melbourne Victoria Australia
| | - Mun Joo Chuei
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
- The Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Melbourne Victoria Australia
| | - Margaret Ayers
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
| | - Yao Lulu Xing
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne Victoria Australia
| | - Ben Emery
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne Victoria Australia
- Department of Anatomy and Neuroscience; The University of Melbourne; Melbourne Victoria Australia
| | - Roberto Cappai
- Department of Pathology; The University of Melbourne; Melbourne Victoria Australia
- The Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Melbourne Victoria Australia
- Department of Pharmacology and Therapeutics; The University of Melbourne; Melbourne Victoria Australia
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6
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Mitew S, Gobius I, Fenlon LR, McDougall SJ, Hawkes D, Xing YL, Bujalka H, Gundlach AL, Richards LJ, Kilpatrick TJ, Merson TD, Emery B. Pharmacogenetic stimulation of neuronal activity increases myelination in an axon-specific manner. Nat Commun 2018; 9:306. [PMID: 29358753 PMCID: PMC5778130 DOI: 10.1038/s41467-017-02719-2] [Citation(s) in RCA: 195] [Impact Index Per Article: 32.5] [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: 03/24/2017] [Accepted: 12/19/2017] [Indexed: 11/09/2022] Open
Abstract
Mounting evidence suggests that neuronal activity influences myelination, potentially allowing for experience-driven modulation of neural circuitry. The degree to which neuronal activity is capable of regulating myelination at the individual axon level is unclear. Here we demonstrate that stimulation of somatosensory axons in the mouse brain increases proliferation and differentiation of oligodendrocyte progenitor cells (OPCs) within the underlying white matter. Stimulated axons display an increased probability of being myelinated compared to neighboring non-stimulated axons, in addition to being ensheathed with thicker myelin. Conversely, attenuating neuronal firing reduces axonal myelination in a selective activity-dependent manner. Our findings reveal that the process of selecting axons for myelination is strongly influenced by the relative activity of individual axons within a population. These observed cellular changes are consistent with the emerging concept that adaptive myelination is a key mechanism for the fine-tuning of neuronal circuitry in the mammalian CNS.
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Affiliation(s)
- Stanislaw Mitew
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Department of Anatomy & Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Ilan Gobius
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Laura R Fenlon
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Stuart J McDougall
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia
| | - David Hawkes
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Yao Lulu Xing
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Helena Bujalka
- Department of Anatomy & Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia.,Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Linda J Richards
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.,Schools of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Trevor J Kilpatrick
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia.,Melbourne Neuroscience Institute, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Tobias D Merson
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia. .,Australian Regenerative Medicine Institute, Monash University, Clayton, VIC, 3800, Australia. .,Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3010, Australia.
| | - Ben Emery
- The Florey Institute of Neuroscience and Mental Health, Parkville, VIC, 3052, Australia. .,Department of Anatomy & Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia. .,Jungers Center for Neurosciences Research, Department of Neurology, Oregon Health and Science University, Portland, OR, 97239, USA.
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7
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Walsh DM, Merson TD, Landman KA, Hughes BD. Evidence for Cooperative Selection of Axons for Myelination by Adjacent Oligodendrocytes in the Optic Nerve. PLoS One 2016; 11:e0165673. [PMID: 27829049 PMCID: PMC5102443 DOI: 10.1371/journal.pone.0165673] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [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: 07/19/2016] [Accepted: 10/14/2016] [Indexed: 01/12/2023] Open
Abstract
The cellular mechanisms that regulate the topographic arrangement of myelin internodes along axons remain largely uncharacterized. Recent clonal analysis of oligodendrocyte morphologies in the mouse optic nerve revealed that adjacent oligodendrocytes frequently formed adjacent internodes on one or more axons in common, whereas oligodendrocytes in the optic nerve were never observed to myelinate the same axon more than once. By modelling the process of axonal selection at the single cell level, we demonstrate that internode length and primary process length constrain the capacity of oligodendrocytes to myelinate the same axon more than once. On the other hand, probabilistic analysis reveals that the observed juxtaposition of myelin internodes among common sets of axons by adjacent oligodendrocytes is highly unlikely to occur by chance. Our analysis may reveal a hitherto unknown level of communication between adjacent oligodendrocytes in the selection of axons for myelination. Together, our analyses provide novel insights into the mechanisms that define the spatial organization of myelin internodes within white matter at the single cell level.
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Affiliation(s)
- Darragh M. Walsh
- School of Mathematics and Statistics, University of Melbourne, Victoria, 3010, Australia
- * E-mail:
| | - Tobias D. Merson
- Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, 3010, Australia
| | - Kerry A. Landman
- School of Mathematics and Statistics, University of Melbourne, Victoria, 3010, Australia
| | - Barry D. Hughes
- School of Mathematics and Statistics, University of Melbourne, Victoria, 3010, Australia
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8
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Walsh DM, Röth PT, Holmes WR, Landman KA, Merson TD, Hughes BD. Is cell migration or proliferation dominant in the formation of linear arrays of oligodendrocytes? J Theor Biol 2016; 406:17-30. [DOI: 10.1016/j.jtbi.2016.06.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 05/05/2016] [Accepted: 06/20/2016] [Indexed: 01/22/2023]
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Huang L, Merson TD, Bourne JA. In vivo whole brain, cellular and molecular imaging in nonhuman primate models of neuropathology. Neurosci Biobehav Rev 2016; 66:104-18. [PMID: 27151822 DOI: 10.1016/j.neubiorev.2016.04.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 03/31/2016] [Accepted: 04/13/2016] [Indexed: 12/22/2022]
Abstract
Rodents have been the principal model to study brain anatomy and function due to their well-mapped brain architecture, rapid reproduction and amenability to genetic modification. However, there are clear limitations, for example their simpler neocortex, necessitating the need to adopt a model that is closer to humans in order to understand human cognition and brain conditions. Nonhuman primates (NHPs) are ideally suited as they are our closest relatives in the animal kingdom but in vivo imaging technologies to study brain structure and function in these species can be challenging. With the surge in NHP research in recent years, scientists have begun adapting imaging technologies, such as two-photon microscopy, for these species. Here we review the various NHP models that exist as well as their use in advanced microscopic and mesoscopic studies. We discuss the challenges in the field and investigate the opportunities that lie ahead.
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Affiliation(s)
- Lieven Huang
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, Victoria 3800, Australia
| | - Tobias D Merson
- The Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, Parkville, Victoria, 3052, Australia
| | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, Victoria 3800, Australia.
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10
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Mitew S, Xing YL, Merson TD. Axonal activity-dependent myelination in development: Insights for myelin repair. J Chem Neuroanat 2016; 76:2-8. [PMID: 26968658 DOI: 10.1016/j.jchemneu.2016.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 09/14/2015] [Revised: 03/01/2016] [Accepted: 03/07/2016] [Indexed: 12/20/2022]
Abstract
Recent advances in transgenic tools have allowed us to peek into the earliest stages of vertebrate development to study axon-glial communication in the control of peri-natal myelination. The emerging role of neuronal activity in regulating oligodendrocyte progenitor cell behavior during developmental myelination has opened up an exciting possibility-a role for neuronal activity in the early stages of remyelination. Recent work from our laboratory and others has also shown that contrary to previously established dogma in the field, complete remyelination up to pre-demyelination levels can be achieved in mouse models of MS by oligodendrogenic neural precursor cells that derive from the adult subventricular zone. These cells are electrically active and can be depolarized, suggesting that neuronal activity may have a modulatory role in their development and remyelination potential. In this review, we summarize recent advances in our understanding of the development of axon-glia communication and apply those same concepts to remyelination, with an emphasis on the particular roles of different sources of oligodendrocyte progenitor cells.
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Affiliation(s)
- Stanislaw Mitew
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - Yao Lulu Xing
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia
| | - Tobias D Merson
- The Florey Institute of Neuroscience and Mental Health, Parkville, Victoria, Australia; Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, Victoria, Australia.
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11
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Merson TD, Bourne JA. Endogenous neurogenesis following ischaemic brain injury: insights for therapeutic strategies. Int J Biochem Cell Biol 2014; 56:4-19. [PMID: 25128862 DOI: 10.1016/j.biocel.2014.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [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: 06/10/2014] [Revised: 07/18/2014] [Accepted: 08/04/2014] [Indexed: 01/19/2023]
Abstract
Ischaemic stroke is among the most common yet most intractable types of central nervous system (CNS) injury in the adult human population. In the acute stages of disease, neurons in the ischaemic lesion rapidly die and other neuronal populations in the ischaemic penumbra are vulnerable to secondary injury. Multiple parallel approaches are being investigated to develop neuroprotective, reparative and regenerative strategies for the treatment of stroke. Accumulating evidence indicates that cerebral ischaemia initiates an endogenous regenerative response within the adult brain that potentiates adult neurogenesis from populations of neural stem and progenitor cells. A major research focus has been to understand the cellular and molecular mechanisms that underlie the potentiation of adult neurogenesis and to appreciate how interventions designed to modulate these processes could enhance neural regeneration in the post-ischaemic brain. In this review, we highlight recent advances over the last 5 years that help unravel the cellular and molecular mechanisms that potentiate endogenous neurogenesis following cerebral ischaemia and are dissecting the functional importance of this regenerative mechanism following brain injury. This article is part of a Directed Issue entitled: Regenerative Medicine: the challenge of translation.
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Affiliation(s)
- Tobias D Merson
- Florey Institute of Neuroscience and Mental Health, Kenneth Myer Building, 30 Royal Parade, Parkville, VIC 3010, Australia.
| | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, Building 75, Level 1 North STRIP 1, Clayton, VIC 3800, Australia.
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12
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Merson TD, Castelletto S, Aharonovich I, Turbic A, Kilpatrick TJ, Turnley AM. Nanodiamonds with silicon vacancy defects for nontoxic photostable fluorescent labeling of neural precursor cells. Opt Lett 2013; 38:4170-3. [PMID: 24321951 DOI: 10.1364/ol.38.004170] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Nanodiamonds (NDs) containing silicon vacancy (SiV) defects were evaluated as a potential biomarker for the labeling and fluorescent imaging of neural precursor cells (NPCs). SiV-containing NDs were synthesized using chemical vapor deposition and silicon ion implantation. Spectrally, SiV-containing NDs exhibited extremely stable fluorescence and narrow bandwidth emission with an excellent signal to noise ratio exceeding that of NDs containing nitrogen-vacancy centers. NPCs labeled with NDs exhibited normal cell viability and proliferative properties consistent with biocompatibility. We conclude that SiV-containing NDs are a promising biomedical research tool for cellular labeling and optical imaging in stem cell research.
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13
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Martin KR, Corlett A, Dubach D, Mustafa T, Coleman HA, Parkington HC, Merson TD, Bourne JA, Porta S, Arbonés ML, Finkelstein DI, Pritchard MA. Over-expression of RCAN1 causes Down syndrome-like hippocampal deficits that alter learning and memory. Hum Mol Genet 2012; 21:3025-41. [PMID: 22511596 DOI: 10.1093/hmg/dds134] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
People with Down syndrome (DS) exhibit abnormal brain structure. Alterations affecting neurotransmission and signalling pathways that govern brain function are also evident. A large number of genes are simultaneously expressed at abnormal levels in DS; therefore, it is a challenge to determine which gene(s) contribute to specific abnormalities, and then identify the key molecular pathways involved. We generated RCAN1-TG mice to study the consequences of RCAN1 over-expression and investigate the contribution of RCAN1 to the brain phenotype of DS. RCAN1-TG mice exhibit structural brain abnormalities in those areas affected in DS. The volume and number of neurons within the hippocampus is reduced and this correlates with a defect in adult neurogenesis. The density of dendritic spines on RCAN1-TG hippocampal pyramidal neurons is also reduced. Deficits in hippocampal-dependent learning and short- and long-term memory are accompanied by a failure to maintain long-term potentiation (LTP) in hippocampal slices. In response to LTP induction, we observed diminished calcium transients and decreased phosphorylation of CaMKII and ERK1/2-proteins that are essential for the maintenance of LTP and formation of memory. Our data strongly suggest that RCAN1 plays an important role in normal brain development and function and its up-regulation likely contributes to the neural deficits associated with DS.
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Affiliation(s)
- Katherine R Martin
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, 3168 Victoria, Australia
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Homman-Ludiye J, Merson TD, Bourne JA. The early postnatal nonhuman primate neocortex contains self-renewing multipotent neural progenitor cells. PLoS One 2012; 7:e34383. [PMID: 22470566 PMCID: PMC3314641 DOI: 10.1371/journal.pone.0034383] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 03/01/2012] [Indexed: 01/14/2023] Open
Abstract
The postnatal neocortex has traditionally been considered a non-neurogenic region, under non-pathological conditions. A few studies suggest, however, that a small subpopulation of neural cells born during postnatal life can differentiate into neurons that take up residence within the neocortex, implying that postnatal neurogenesis could occur in this region, albeit at a low level. Evidence to support this hypothesis remains controversial while the source of putative neural progenitors responsible for generating new neurons in the postnatal neocortex is unknown. Here we report the identification of self-renewing multipotent neural progenitor cells (NPCs) derived from the postnatal day 14 (PD14) marmoset monkey primary visual cortex (V1, striate cortex). While neuronal maturation within V1 is well advanced by PD14, we observed cells throughout this region that co-expressed Sox2 and Ki67, defining a population of resident proliferating progenitor cells. When cultured at low density in the presence of epidermal growth factor (EGF) and/or fibroblast growth factor 2 (FGF-2), dissociated V1 tissue gave rise to multipotent neurospheres that exhibited the ability to differentiate into neurons, oligodendrocytes and astrocytes. While the capacity to generate neurones and oligodendrocytes was not observed beyond the third passage, astrocyte-restricted neurospheres could be maintained for up to 6 passages. This study provides the first direct evidence for the existence of multipotent NPCs within the postnatal neocortex of the nonhuman primate. The potential contribution of neocortical NPCs to neural repair following injury raises exciting new possibilities for the field of regenerative medicine.
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Affiliation(s)
- Jihane Homman-Ludiye
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Tobias D. Merson
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
- Florey Neuroscience Institutes and Centre for Neuroscience, University of Melbourne, Melbourne, Victoria, Australia
- * E-mail: (TM); (JB)
| | - James A. Bourne
- Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
- * E-mail: (TM); (JB)
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Hewitt CA, Ling KH, Merson TD, Simpson KM, Ritchie ME, King SL, Pritchard MA, Smyth GK, Thomas T, Scott HS, Voss AK. Gene network disruptions and neurogenesis defects in the adult Ts1Cje mouse model of Down syndrome. PLoS One 2010; 5:e11561. [PMID: 20661276 PMCID: PMC2905390 DOI: 10.1371/journal.pone.0011561] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2010] [Accepted: 05/31/2010] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Down syndrome (DS) individuals suffer mental retardation with further cognitive decline and early onset Alzheimer's disease. METHODOLOGY/PRINCIPAL FINDINGS To understand how trisomy 21 causes these neurological abnormalities we investigated changes in gene expression networks combined with a systematic cell lineage analysis of adult neurogenesis using the Ts1Cje mouse model of DS. We demonstrated down regulation of a number of key genes involved in proliferation and cell cycle progression including Mcm7, Brca2, Prim1, Cenpo and Aurka in trisomic neurospheres. We found that trisomy did not affect the number of adult neural stem cells but resulted in reduced numbers of neural progenitors and neuroblasts. Analysis of differentiating adult Ts1Cje neural progenitors showed a severe reduction in numbers of neurons produced with a tendency for less elaborate neurites, whilst the numbers of astrocytes was increased. CONCLUSIONS/SIGNIFICANCE We have shown that trisomy affects a number of elements of adult neurogenesis likely to result in a progressive pathogenesis and consequently providing the potential for the development of therapies to slow progression of, or even ameliorate the neuronal deficits suffered by DS individuals.
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Affiliation(s)
- Chelsee A. Hewitt
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Pathology, The Peter MacCallum Cancer Centre, Melbourne, Australia
| | - King-Hwa Ling
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Molecular Pathology, The Centre for Cancer Biology, The Institute of Medical and Veterinary Science and The Hanson Institute, SA Pathology, and The Adelaide Cancer Research Institute, School of Medicine, University of Adelaide, Adelaide, Australia
- Department of Obstetrics and Gynaecology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia
| | - Tobias D. Merson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Ken M. Simpson
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Matthew E. Ritchie
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Sarah L. King
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Melanie A. Pritchard
- Department of Biochemistry and Molecular Biology, Monash University, Victoria, Australia
| | - Gordon K. Smyth
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
| | - Tim Thomas
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
| | - Hamish S. Scott
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Molecular Pathology, The Centre for Cancer Biology, The Institute of Medical and Veterinary Science and The Hanson Institute, SA Pathology, and The Adelaide Cancer Research Institute, School of Medicine, University of Adelaide, Adelaide, Australia
| | - Anne K. Voss
- The Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Australia
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Merson TD, Binder MD, Kilpatrick TJ. Role of cytokines as mediators and regulators of microglial activity in inflammatory demyelination of the CNS. Neuromolecular Med 2010; 12:99-132. [PMID: 20411441 DOI: 10.1007/s12017-010-8112-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Accepted: 02/26/2010] [Indexed: 12/11/2022]
Abstract
As the resident innate immune cells of the central nervous system (CNS), microglia fulfil a critical role in maintaining tissue homeostasis and in directing and eliciting molecular responses to CNS damage. The human disease Multiple Sclerosis and animal models of inflammatory demyelination are characterized by a complex interplay between degenerative and regenerative processes, many of which are regulated and mediated by microglia. Cellular communication between microglia and other neural and immune cells is controlled to a large extent by the activity of cytokines. Here we review the role of cytokines as mediators and regulators of microglial activity in inflammatory demyelination, highlighting their importance in potentiating cell damage, promoting neuroprotection and enhancing cellular repair in a context-dependent manner.
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Affiliation(s)
- Tobias D Merson
- Florey Neuroscience Institutes, Centre for Neuroscience, University of Melbourne, Parkville, VIC, 3010, Australia.
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17
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Young KM, Merson TD, Sotthibundhu A, Coulson EJ, Bartlett PF. p75 neurotrophin receptor expression defines a population of BDNF-responsive neurogenic precursor cells. J Neurosci 2007; 27:5146-55. [PMID: 17494700 PMCID: PMC6672366 DOI: 10.1523/jneurosci.0654-07.2007] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Although our understanding of adult neurogenesis has increased dramatically over the last decade, confusion still exists regarding both the identity of the stem cell responsible for neuron production and the mechanisms that regulate its activity. Here we show, using flow cytometry, that a small population of cells (0.3%) within the stem cell niche of the rat subventricular zone (SVZ) expresses the p75 neurotrophin receptor (p75(NTR)) and that these cells are responsible for neuron production in both newborn and adult animals. In the adult, the p75(NTR)-positive population contains all of the neurosphere-producing precursor cells, whereas in the newborn many of the precursor cells are p75(NTR) negative. However, at both ages, only the neurospheres derived from p75(NTR)-positive cells are neurogenic. We also show that neuron production from p75(NTR)-positive but not p75(NTR)-negative precursors is greatly enhanced after treatment with brain-derived neurotrophic factor (BDNF) or nerve growth factor. This effect appears to be mediated specifically by p75(NTR), because precursor cells from p75(NTR)-deficient mice show a 70% reduction in their neurogenic potential in vitro and fail to respond to BDNF treatment. Furthermore, adult p75(NTR)-deficient mice have significantly reduced numbers of PSA-NCAM (polysialylated neural cell adhesion molecule)-positive SVZ neuroblasts in vivo and a lower olfactory bulb weight. Thus, p75(NTR) defines a discrete population of highly proliferative SVZ precursor cells that are able to respond to neurotrophin activation by increasing neuroblast generation, making this pathway the most likely mechanism for the increased neurogenesis that accompanies raised BDNF levels in a variety of disease and behavioral situations.
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Affiliation(s)
- Kaylene M. Young
- Queensland Brain Institute, The University of Queensland, Brisbane QLD 4072, Australia
- The Walter and Eliza Hall Institute for Medical Research, Melbourne VIC 3050, Australia, and
| | - Tobias D. Merson
- Howard Florey Institute, The University of Melbourne, Melbourne VIC 3010, Australia
| | - Areechun Sotthibundhu
- Queensland Brain Institute, The University of Queensland, Brisbane QLD 4072, Australia
| | - Elizabeth J. Coulson
- Queensland Brain Institute, The University of Queensland, Brisbane QLD 4072, Australia
| | - Perry F. Bartlett
- Queensland Brain Institute, The University of Queensland, Brisbane QLD 4072, Australia
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18
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Abstract
The adult mammalian brain maintains populations of neural stem cells within discrete proliferative zones. Understanding of the molecular mechanisms regulating adult neural stem cell function is limited. Here, we show that MYST family histone acetyltransferase Querkopf (Qkf, Myst4, Morf)-deficient mice have cumulative defects in adult neurogenesis in vivo, resulting in declining numbers of olfactory bulb interneurons, a population of neurons produced in large numbers during adulthood. Qkf-deficient mice have fewer neural stem cells and fewer migrating neuroblasts in the rostral migratory stream. Qkf gene expression is strong in the neurogenic subventricular zone. A population enriched in multipotent cells can be isolated from this region on the basis of Qkf gene expression. Neural stem cells/progenitor cells isolated from Qkf mutant mice exhibited a reduced self-renewal capacity and a reduced ability to produce differentiated neurons. Together, our data show that Qkf is essential for normal adult neurogenesis.
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Affiliation(s)
- Tobias D. Merson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Mathew P. Dixon
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Caitlin Collin
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Rodney L. Rietze
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Perry F. Bartlett
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Tim Thomas
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
| | - Anne K. Voss
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3050, Australia
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Emery B, Merson TD, Snell C, Young KM, Ernst M, Kilpatrick TJ. SOCS3 negatively regulates LIF signaling in neural precursor cells. Mol Cell Neurosci 2006; 31:739-47. [PMID: 16497512 DOI: 10.1016/j.mcn.2006.01.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2005] [Revised: 12/23/2005] [Accepted: 01/03/2006] [Indexed: 11/26/2022] Open
Abstract
Cytokines that signal through the LIFRbeta/gp130 receptor complex, including LIF and CNTF, promote the self-renewal of embryonic and adult neural precursor cells (NPCs). In non-CNS tissues, the protein suppressor of cytokine signaling-3 (SOCS3) negatively regulates signaling through gp130. Here, we analyze the role of SOCS3 in inhibiting LIF signaling in NPCs in vitro. SOCS3 is rapidly expressed by NPCs in response to LIF stimulation, with this expression largely dependent on recruitment of STAT proteins to the activated gp130 receptor. Proliferating NPC cultures can be generated from SOCS3 knockout (SOCS3KO/KO) embryos and display prolonged STAT3 phosphorylation and induction of the GFAP gene in response to LIF. In comparison with SOCS3 wild-type (SOCS3WT/WT) NPCs, SOCS3KO/KO cultures display enhanced self-renewal capacity. However, the clonal potential of SOCS3WT/WT but not SOCS3KO/KO NPCs is enhanced by exogenous LIF. Thus, SOCS3 acts as a negative regulator of LIF signaling in NPCs.
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Affiliation(s)
- B Emery
- Multiple Sclerosis Group, The Howard Florey Institute, University of Melbourne, Melbourne, Victoria 3010, Australia
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Krebs DL, Metcalf D, Merson TD, Voss AK, Thomas T, Zhang JG, Rakar S, O'bryan MK, Willson TA, Viney EM, Mielke LA, Nicola NA, Hilton DJ, Alexander WS. Development of hydrocephalus in mice lacking SOCS7. Proc Natl Acad Sci U S A 2004; 101:15446-51. [PMID: 15494444 PMCID: PMC524464 DOI: 10.1073/pnas.0406870101] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SOCS7 is a member of the suppressor of cytokine signaling (SOCS) family of proteins (SOCS1-SOCS7 and CIS). SOCS proteins are composed of an N-terminal domain of variable length, a central Src homology 2 domain, and a C-terminal SOCS box. Biochemical and genetic studies have revealed that SOCS1, SOCS2, SOCS3, and CIS play an important role in the termination of cytokine and growth factor signaling. However, the biological actions of other SOCS proteins are less well defined. To investigate the physiological role of SOCS7, we have used gene targeting to generate mice that lack expression of the Socs7 gene. Socs7-/- mice were born in expected numbers, were fertile, and did not exhibit defects in hematopoiesis or circulating glucose or insulin concentrations. However, Socs7-/- mice were 7-10% smaller than their wild-type littermates, and within 15 weeks of age approximately 50% of the Socs7-/- mice died as a result of hydrocephalus that was characterized by cranial distortion, dilation of the ventricular system, reduced thickness of the cerebral cortex, and disorganization of the subcommissural organ. In situ hybridization studies revealed prominent expression of Socs7 in the brain, suggestive of an important functional role of SOCS7 in this organ.
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Affiliation(s)
- Danielle L Krebs
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Victoria 3050, Australia
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Keramidaris E, Merson TD, Steeber DA, Tedder TF, Tang ML. L-selectin and intercellular adhesion molecule 1 mediate lymphocyte migration to the inflamed airway/lung during an allergic inflammatory response in an animal model of asthma. J Allergy Clin Immunol 2001; 107:734-8. [PMID: 11295667 DOI: 10.1067/mai.2001.114050] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
T lymphocytes play a critical role in the development of allergic inflammation in asthma. Early in the allergic response, T lymphocytes migrate from the circulation into the lung to initiate and propagate airway inflammation. The adhesion molecules that mediate lymphocyte entry into inflamed lung have not been defined. This study directly examined the roles of L-selectin and intercellular adhesion molecule 1 (ICAM-1) in lymphocyte migration to the lung during an allergic inflammatory response in an animal model of asthma. Short-term (1 hour) in vivo migration assays and various combinations of adhesion molecule-deficient and wild-type mice were used. Migration of in vivo activated lymphocytes into inflamed lung was significantly greater than entry of resting lymphocytes into noninflamed lung (24.5% +/- 2.7% vs 9.5% +/- 1.3%, P =.001). Migration of activated lymphocytes into inflamed lung was inhibited by 30% in the absence of L-selectin (17.3% +/- 1.3%, P =.04), 47% in the absence of cell surface ICAM-1 (13.0% +/- 2.5%, P =.01), and 47% in the absence of endothelial ICAM-1 (13.0% +/- 2.5%, P =.01). Loss of ICAM-1 on both lymphocytes and lung endothelium inhibited lymphocyte migration by 60% (9.8% +/- 1.8%, P =.002). These findings demonstrate clear roles for both L-selectin and ICAM-1 in lymphocyte migration to the lung during an allergic inflammatory response, with ICAM-1 playing a greater role.
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Affiliation(s)
- E Keramidaris
- Department of Immunology, Royal Children's Hospital, Flemington Rd., Parkville, VIC 3052, Australia
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