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Immune privilege as an intrinsic CNS property: astrocytes protect the CNS against T-cell-mediated neuroinflammation. Mediators Inflamm 2013; 2013:320519. [PMID: 24023412 PMCID: PMC3760105 DOI: 10.1155/2013/320519] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 07/09/2013] [Indexed: 12/26/2022] Open
Abstract
Astrocytes have many functions in the central nervous system (CNS). They support differentiation and homeostasis of neurons and influence synaptic activity. They are responsible for formation of the blood-brain barrier (BBB) and make up the glia limitans. Here, we review their contribution to neuroimmune interactions and in particular to those induced by the invasion of activated T cells. We discuss the mechanisms by which astrocytes regulate pro- and anti-inflammatory aspects of T-cell responses within the CNS. Depending on the microenvironment, they may become potent antigen-presenting cells for T cells and they may contribute to inflammatory processes. They are also able to abrogate or reprogram T-cell responses by inducing apoptosis or secreting inhibitory mediators. We consider apparently contradictory functions of astrocytes in health and disease, particularly in their interaction with lymphocytes, which may either aggravate or suppress neuroinflammation.
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Abstract
Controlled clinical trials of cell transplantation for Parkinson's disease yielded disappointing results. Significant long-term functional improvement was not observed and cell survival was low. Although the brain was traditionally considered as "immunologically privileged" recent findings demonstrated late increase in the number of microglia around the grafts, therefore implying an involvement of immune mechanisms. The immunology of organ and cell transplantation to other body locations is scrupulously investigated and significant stepping-stones have been achieved. Ample evidence regarding the role of antigen-presenting cells in graft rejection has been documented. However, this knowledge did not benefit the discipline of cell transplantation to the central nervous system, and the minimal consideration of potential immune responses remain empirical in nature. In this review we summarize current knowledge of the major histo-compatibility complex and its role in transplant immunology. Resident cells of the brain that take part in immune responses are also discussed. Based on this information we hypothesize that the immune mechanisms involved with the long-term graft failure of cell transplantation to the central nervous system are likely to be chronic, and not acute, rejection. This, in turn, should have significant importance in the choice of anti-rejection drugs to be used.
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Affiliation(s)
- Anat R Tambur
- Department of Neurosurgery, University of Illinois at Chicago, Chicago 60612, USA.
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3
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Griffiths MR, Gasque P, Neal JW. The regulation of the CNS innate immune response is vital for the restoration of tissue homeostasis (repair) after acute brain injury: a brief review. Int J Inflam 2010; 2010:151097. [PMID: 21152121 PMCID: PMC2989866 DOI: 10.4061/2010/151097] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 01/06/2010] [Accepted: 04/28/2010] [Indexed: 12/12/2022] Open
Abstract
Neurons and glia respond to acute injury by participating in the CNS innate immune response. This involves the recognition and clearance of "not self " pathogens and "altered self " apoptotic cells. Phagocytic receptors (CD14, CD36, TLR-4) clear "not self" pathogens; neurons and glia express "death signals" to initiate apoptosis in T cells.The complement opsonins C1q, C3, and iC3b facilitate the clearance of apoptotic cells by interacting with CR3 and CR4 receptors. Apoptotic cells are also cleared by the scavenger receptors CD14, Prs-R, TREM expressed by glia. Serpins also expressed by glia counter the neurotoxic effects of thrombin and other systemic proteins that gain entry to the CNS following injury. Complement pathway and T cell activation are both regulated by complement regulatory proteins expressed by glia and neurons. CD200 and CD47 are NIRegs expressed by neurons as "don't eat me" signals and they inhibit microglial activity preventing host cell attack. Neural stem cells regulate T cell activation, increase the Treg population, and suppress proinflammatory cytokine expression. Stem cells also interact with the chemoattractants C3a, C5a, SDF-1, and thrombin to promote stem cell migration into damaged tissue to support tissue homeostasis.
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Affiliation(s)
- M. R. Griffiths
- Deptartment of Medical Biochemistry, University Hospital of Wales, Cardiff University Medical School, Cardiff CF14 4XN, UK
| | - P. Gasque
- Deptartment of Medical Biochemistry, University Hospital of Wales, Cardiff University Medical School, Cardiff CF14 4XN, UK
- University Labo. Biochimie et Genetique Moleculaire, Facilities de Science et Technologies, Universite de La Reunion, 15 Avenue Rene Cassin Saint Denis, Ile de la Reunion, BP 7151, 97715, France
| | - J. W. Neal
- Deptartment of Histopathology, University Hospital of Wales, Cardiff University Medical School, Cardiff CF14 4XN, UK
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Meyer zu Hörste G, Heidenreich H, Mausberg AK, Lehmann HC, ten Asbroek ALMA, Saavedra JT, Baas F, Hartung HP, Wiendl H, Kieseier BC. Mouse Schwann cells activate MHC class I and II restricted T-cell responses, but require external peptide processing for MHC class II presentation. Neurobiol Dis 2009; 37:483-90. [PMID: 19914379 DOI: 10.1016/j.nbd.2009.11.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2009] [Revised: 11/04/2009] [Accepted: 11/06/2009] [Indexed: 11/30/2022] Open
Abstract
Schwann cells are the myelinating glia cells of the peripheral nervous system (PNS). In inflammatory neuropathies like the Guillain-Barré syndrome (GBS) Schwann cells become target of an autoimmune response, but may also modulate local inflammation. Here, we tested the functional relevance of Schwann cell derived MHC expression in an in vitro coculture system. Mouse Schwann cells activated proliferation of ovalbumin specific CD8+ T cells when ovalbumin protein or MHC class I restricted ovalbumin peptide (Ova(257-264) SIINFEKL) was added and after transfection with an ovalbumin coding vector. Schwann cells activated proliferation of ovalbumin specific CD4+ T cells in the presence of MHC class II restricted ovalbumin peptide (Ova(323-339) ISQAVHAAHAEINEAGR). CD4+ T-cell proliferation was not activated by ovalbumin protein or transfection with an ovalbumin coding vector. This indicates that Schwann cells express functionally active MHC class I and II molecules. In this study, however, Schwann cells lacked the ability to process exogenous antigen or cross-present endogenous antigen into the MHC class II presentation pathway. Thus, antigen presentation may be a pathological function of Schwann cells exacerbating nerve damage in inflammatory neuropathies.
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Hamby ME, Hewett JA, Hewett SJ. TGF-beta1 reduces the heterogeneity of astrocytic cyclooxygenase-2 and nitric oxide synthase-2 gene expression in a stimulus-independent manner. Prostaglandins Other Lipid Mediat 2007; 85:115-24. [PMID: 18194875 DOI: 10.1016/j.prostaglandins.2007.11.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2007] [Revised: 11/16/2007] [Accepted: 11/21/2007] [Indexed: 11/30/2022]
Abstract
Transforming growth factor-beta1 (TGF-beta1) is upregulated by inflammatory mediators in several neurological diseases/disorders where it either participates in the pathology or provides protection. Often, the biological outcome of TGF-beta1 is dependent upon changes in gene expression. Recently, we demonstrated that TGF-beta1 enhances astrocytic nitric oxide production induced by lipopolysaccharide (LPS) plus interferon-gamma (IFNgamma) by increasing the number of astrocytes in a population that express NOS-2. The purpose of this study was twofold: (1) to determine whether this effect occurs more generally by assessing the effect of TGF-beta1 on another pro-inflammatory gene, cyclooxygenase-2 (COX-2); and (2) to assess stimulus specificity. We found that TGF-beta1 augmented LPS plus IFNgamma-induced COX-2 mRNA and protein expression, by nearly tripling the number of astrocytes that express COX-2. The effect was not stimulus-specific as TGF-beta1 enhanced the number of astrocytes that expressed both COX-2 and NOS-2 protein when either IL-1beta or TNFalpha was used in lieu of LPS. Collectively, these results suggest that TGF-beta1 augments overall protein expression levels of select pro-inflammatory genes in astrocytes in a promiscuous manner by reducing the magnitude of noise in the cellular population.
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Affiliation(s)
- Mary E Hamby
- Department of Neuroscience, University of Connecticut Health Center, Farmington, CT 06030, USA
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6
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Abstract
The peripheral nervous system (PNS) is a target for heterogenous immune attacks mediated by different components of the systemic immune compartment. T cells, B cells, and macrophages can interact with endogenous, partially immune-competent glial cells and contribute to local inflammation. Cellular and humoral immune functions of Schwann cells have been well characterized in vitro. In addition, the interaction of the humoral and cellular immune system with the cellular and extracellular components in the PNS may determine the extent of tissue inflammation and repair processes such as remyelination and neuronal outgrowth. The animal model experimental autoimmune neuritis (EAN) allows direct monitoring of these immune responses in vivo. In EAN contributions to regulate autoimmunity in the PNS are made by adhesion molecules and by cytokines that orchestrate cellular interactions. The PNS has a significant potential to eliminate T cell inflammation via apoptosis, which is almost lacking in other tissues such as muscle and skin. In vitro experiments suggest different scenarios how specific cellular and humoral elements in the PNS may sensitize autoreactive T cells for apoptosis in vivo. Interestingly several conventional and novel immunotherapeutic approaches like glucocorticosteroids and high-dose antigen therapy induce T cell apoptosis in situ in EAN. A better understanding of immune regulation and its failure in the PNS may help to develop improved, more specific immunotherapies.
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Affiliation(s)
- Ralf Gold
- Department of Neurology, Clinical Research Unit for Multiple Sclerosis, Julius‐Maximilians‐Universität Würzburg, Germany
| | - Juan J. Archelos
- Department of Neurology, Multiple Sclerosis and Neuroimmunology Research Group, Karl‐Franzens‐Universität Graz, Austria
| | - Hans‐Peter Hartung
- Department of Neurology, Multiple Sclerosis and Neuroimmunology Research Group, Karl‐Franzens‐Universität Graz, Austria
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7
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Abstract
A successful outcome for the host of virus infection of the central nervous system (CNS) requires the elimination of the virus without damage to essential non-renewable cells, such as neurons. As a result, inflammatory responses must be tightly controlled, and many unique mechanisms seem to contribute to this control. In addition to being important causes of human disease, RNA viruses that infect the CNS provide useful models in which to study immune responses in the CNS. Recent work has shown the importance of innate immune responses in the CNS in controlling virus infection. And advances have been made in assessing the relative roles of cytotoxic T cells, antibodies and cytokines in the clearance of viruses from neurons, glial cells and meningeal cells.
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Affiliation(s)
- Diane E Griffin
- W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland 21205, USA.
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Taniguchi Y, Ono K, Yoshida S, Tanaka R. Antigen-presenting capability of glial cells under glioma-harboring conditions and the effect of glioma-derived factors on antigen presentation. J Neuroimmunol 2000; 111:177-85. [PMID: 11063836 DOI: 10.1016/s0165-5728(00)00361-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The antigen-presenting capability of syngeneic rat glial cells was investigated under glioma-harboring conditions. Microglia induced a significant proliferation of glioma-primed splenocytes, but astrocytes did not. Furthermore, astrocytes suppressed the accessory cell function of microglia. The presence of both indomethacin and anti-interleukin (IL)-10 neutralizing antibody during priming of microglia enhanced splenocyte proliferation. The glioma culture supernatants down-regulated the interferon-gamma-induced expression of major histocompatibility complex class II molecules on microglia. The down-regulation was blocked by indomethacin and anti-IL-10 antibody. The results suggest that microglia but not astrocytes may function as antigen-presenting cells in glioma, and that glioma may suppress the antigen-presenting abilities of microglia.
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Affiliation(s)
- Y Taniguchi
- Department of Neurosurgery, Brain Research Institute, Niigata University, Asahimachi 1, 951-8585, Niigata, Japan
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McCluskey LP, Lampson LA. Local neurochemicals and site-specific immune regulation in the CNS. J Neuropathol Exp Neurol 2000; 59:177-87. [PMID: 10744056 DOI: 10.1093/jnen/59.3.177] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Although it is often described as "immunologically privileged," the brain can display vigorous immune activity, both clinically and experimentally. The underlying control mechanisms are under active study. Here we shift attention from the brain as a whole to its diverse microenvironments. We review evidence that immune regulation in the brain is site-specific, and that local neurochemicals contribute to the site-specific control. Key points are illustrated by recent work from a rat model in which local injection of the proinflammatory cytokine, IFN-gamma, was used to modulate 2 essential aspects of the cell-mediated immune response: T cell entry from the blood, and expression of the MHC proteins that are needed to present antigen to the newly entered T cells. A growing number of neurologic disorders are known to be exacerbated by the immune/inflammatory network. Understanding the factors that influence local immune function may help explain the distribution of localized CNS damage and, more importantly, may suggest new therapeutic approaches for both desirable and unwanted responses.
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Affiliation(s)
- L P McCluskey
- Department of Surgery (Neurosurgery), Brigham & Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA
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Primary central nervous system lymphomas are derived from germinal-center B cells and show a preferential usage of the V4-34 gene segment. THE AMERICAN JOURNAL OF PATHOLOGY 1999; 155:2077-86. [PMID: 10595937 PMCID: PMC1866926 DOI: 10.1016/s0002-9440(10)65526-5] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Primary central nervous system lymphomas (PCNSLs) have recently received considerable clinical attention due to their increasing incidence. To clarify the histogenetic origin of these intriguing neoplasms, PCNSLs from 10 HIV-negative patients were analyzed for immunoglobulin (Ig) gene rearrangements. All tumors exhibited clonal IgH gene rearrangements. Of the 10 cases, 5 used the V4-34 gene segment, and all of these lymphomas shared an amino acid exchange from glycine to aspartate due to a mutation in the first codon of the complementarity-determining region 1. No preferential usage of D(H), J(H), V(kappa), J(kappa), V(lambda), or J(lambda) gene segments was observed. All potentially functional rearrangements exhibited somatic mutations. The pattern of somatic mutations indicated selection of the tumor cells (or their precursors) for expression of a functional antibody. Mean mutation frequencies of 13. 2% and 8.3% were detected for the heavy and light chains, respectively, thereby exceeding other lymphoma entities. Cloning experiments of three tumors showed ongoing mutation in at least one case. These data suggest that PCNSLs are derived from highly mutated germinal-center B cells. The frequent usage of the V4-34 gene and the presence of a shared replacement mutation may indicate that the tumor precursors recognized a shared (super) antigen.
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11
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Abstract
Cytokines and chemokines have been implicated in contributing to the initiation, propagation and regulation of immune and inflammatory responses. Also, these soluble mediators have important roles in contributing to a wide array of neurological diseases such as multiple sclerosis, AIDS Dementia Complex, stroke and Alzheimer's disease. Cytokines and chemokines are synthesized within the central nervous system by glial cells and neurons, and have modulatory functions on these same cells via interactions with specific cell-surface receptors. In this article, I will discuss the ability of glial cells and neurons to both respond to, and synthesize, a variety of cytokines. The emphasize will be on three select cytokines; interferon-gamma (IFN-gamma), a cytokine with predominantly proinflammatory effects; interleukin-6 (IL-6), a cytokine with both pro- and anti-inflammatory properties; and transforming growth factor-beta (TGF-beta), a cytokine with predominantly immunosuppressive actions. The significance of these cytokines to neurological diseases with an immunological component will be discussed.
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Affiliation(s)
- E N Benveniste
- Department of Cell Biology, University of Alabama at Birmingham, 35294-0005, USA.
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12
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Abstract
The brain constitutes an environment that is specifically designed to accommodate, regulate and shape immune responses. On one hand, the central nervous system (CNS) has traditionally been regarded as an immunologically privileged organ, owing to local tissue barrier and immunosuppressive microenvironment. On the other hand, activated microglia and astrocytes express MHC and adhesion/costimulatory molecules, release reactive oxygen intermediates and cytokines, and participate in local immune regulation. Bidirectional interactions between immune and neuroglial components occur in response to infectious and traumatic lesions. Glial cells may facilitate and amplify immune effector mechanisms within the CNS. Cytokines and chemokines within the CNS constitute a specialized CNS-cytokine network, and regulate the development and recovery from autoimmune diseases within the CNS. The interactions between glial cells and lymphoid cells are constituents of a complex immune regulatory system within the CNS. New data on the cross-talk between the CNS and the immune systems are envisaged, and followed by an attempt to create a synthesis of current knowledge.
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Affiliation(s)
- B G Xiao
- Division of Neurology, Karolinska Institute, Huddinge University Hospital, Stockholm, Sweden
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13
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Deckert-Schlüter M, Buck C, Weiner D, Kaefer N, Rang A, Hof H, Wiestler OD, Schlüter D. Interleukin-10 downregulates the intracerebral immune response in chronic Toxoplasma encephalitis. J Neuroimmunol 1997; 76:167-76. [PMID: 9184647 DOI: 10.1016/s0165-5728(97)00047-7] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The expression of the immunosuppressive cytokine interleukin (IL)-10 in the normal and Toxoplasma gondii-infected murine brain was analysed. Microglia/macrophages expressed IL-10 at the mRNA and protein level in the normal brain. In Toxoplasma encephalitis (TE), CD4+ and CD8+ T-cells also contributed to the upregulated IL-10 production. Neutralization of endogenous IL-10 in chronic TE reduced the intracerebral parasitic load and increased the number of immune cells and the production of protective cytokines. These findings indicate that intracerebral expression of IL-10 interferes with the immune response in TE and may contribute to parasite persistence in the brain.
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Pedersen EB, McNulty JA, Castro AJ, Fox LM, Zimmer J, Finsen B. Enriched immune-environment of blood-brain barrier deficient areas of normal adult rats. J Neuroimmunol 1997; 76:117-31. [PMID: 9184641 DOI: 10.1016/s0165-5728(97)00038-6] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The circumventricular organs (CVOs) in the brain are without a blood-brain barrier (BBB) and as such directly exposed to blood plasma constituents and blood-borne pathogens. In light of previous studies showing discrepancies regarding the immunocompetence of these organs, we initiated the present study to provide a comprehensive immunohistochemical analysis of the cellular expression of immune-associated antigens within the pineal gland, area postrema and the subfornical organ. In all CVOs, subpopulations of cells morphologically similar to complement receptor type 3 immunoreactive microglial/macrophage cells expressed major histocompatibility complex (MHC) class II antigen, leucocyte common antigen (LCA/CD45), as well as CD4 and ED1 antigen. Based on morphological criteria the MHC class II antigen expressing cells could be grouped into a major population of classical parenchymal and perivascular ramified microglial cells and a minor population presenting itself as scattered or small groups of rounded macrophage-like cells. CD4 and ED1 antigen were expressed by both cell types. CD45 was preferentially expressed by macrophage-like cells. MHC class I antigen was expressed by the vascular endothelium in both BBB-protected and BBB-deficient areas and was additionally present as a lattice-like network throughout the BBB-deficient parenchyma in all CVOs. The results suggest that the BBB-free areas of the brain besides being constantly surveyed by blood-borne macrophages, possess an intrinsic immune surveillance system based on resting and activated microglial cells, which may function as a non-endothelial, cellular barrier against blood-borne pathogens.
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Affiliation(s)
- E B Pedersen
- Department of Anatomy and Cell Biology, University of Odense, Denmark.
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Cash E, Rott O. Microglial cells qualify as the stimulators of unprimed CD4+ and CD8+ T lymphocytes in the central nervous system. Clin Exp Immunol 1994; 98:313-8. [PMID: 7955538 PMCID: PMC1534421 DOI: 10.1111/j.1365-2249.1994.tb06143.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The potential of central nervous system (CNS)-derived cells for initiating T cell responses is not known. Using the capacity of unprimed T cells to respond to allogeneic determinants on antigen-presenting cells (APC), we assessed the ability of microglial cells to act as stimulators of primary T cell responses in vitro. For this purpose, microglial cells were activated with lipopolysaccharide (LPS), interferon-gamma (IFN-gamma), or by phagocytosis of progenitor oligodendrocytes and subsequently tested for their ability to induce a proliferative response of naive, resting T cells. Activated microglial cells induced a significant proliferation of virgin, alloreactive CD4+ and CD8+ T lymphocytes, with a more substantial response of highly purified CD4+ than of CD8-expressing T cells. Phagocytosis activation was the most efficient stimulus to induce this APC competence on microglial cells. By contrast, IFN-gamma-pretreated, MHC-expressing astrocytes were unable to induce similar responses of alloreactive CD4+ or CD8+ T cells under the same experimental conditions. Collectively, our data suggest the role of activated microglia as the fully immunocompetent accessory cell population of the CNS.
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Affiliation(s)
- E Cash
- INSERM U283, Cochin Hospital, Paris, France
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Laping NJ, Teter B, Nichols NR, Rozovsky I, Finch CE. Glial fibrillary acidic protein: regulation by hormones, cytokines, and growth factors. Brain Pathol 1994; 4:259-75. [PMID: 7952267 DOI: 10.1111/j.1750-3639.1994.tb00841.x] [Citation(s) in RCA: 178] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Levels of glial fibrillary acidic protein (GFAP), an astrocyte-specific intermediate filament protein, are altered during development and aging, GFAP also responds dynamically to neurodegenerative lesions. Changes in GFAP expression can occur at both transcriptional and translational levels. Modulators of GFAP expression include steroids, cytokines, and growth factors. GFAP expression also shows brain region-specific responses to sex steroids and of astrocyte-neuronal interactions. The 5'-upstream sequences of rat, mouse, and human are compared for the presence of response elements that are candidates for transcriptional regulation of GFAP. We propose that the regulation of the GFAP gene has evolved a system of controls that allow integrated responses to neuroendocrine and inflammatory modulators.
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Affiliation(s)
- N J Laping
- Neurogerontology Division, Andrus Gerontology Center, University of Southern California, Los Angeles 90089-0191
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McMillian MK, Thai L, Hong JS, O'Callaghan JP, Pennypacker KR. Brain injury in a dish: a model for reactive gliosis. Trends Neurosci 1994; 17:138-42. [PMID: 7517589 DOI: 10.1016/0166-2236(94)90086-8] [Citation(s) in RCA: 148] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Reactive gliosis is a powerful response to brain injury and subsequent neuronal damage in vivo. Neuronal cell cultures are now well established as assays to study this process in vitro. However, equivalent studies of purified glial cell populations have only recently been achieved, following the realization that glial cells produce many of the neuropeptides, transmitters and growth factors that are produced also by neurons. There is now scope for studies in vitro that use mixed, identified populations of glial and neuronal cells to dissect the interactions between the two. Such cultures also lend themselves to assays for potential therapeutic strategies for brain injury that take account of all the different cell types found in the brain.
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Affiliation(s)
- M K McMillian
- Laboratory of Molecular and Integrative Neurosciences, National Institute of Environmental Health Sciences, National Institutes of Health
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