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Duan S, Sawyer TW, Sontz RA, Wieland BA, Diaz AF, Merchant JL. GFAP-directed Inactivation of Men1 Exploits Glial Cell Plasticity in Favor of Neuroendocrine Reprogramming. Cell Mol Gastroenterol Hepatol 2022; 14:1025-1051. [PMID: 35835391 PMCID: PMC9490044 DOI: 10.1016/j.jcmgh.2022.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 06/16/2022] [Accepted: 06/28/2022] [Indexed: 01/31/2023]
Abstract
BACKGROUND & AIMS Efforts to characterize the signaling mechanisms that underlie gastroenteropancreatic neoplasms (GEP-NENs) are precluded by a lack of comprehensive models that recapitulate pathogenesis. Investigation into a potential cell-of-origin for gastrin-secreting NENs revealed a non-cell autonomous role for loss of menin in neuroendocrine cell specification, resulting in an induction of gastrin in enteric glia. Here, we investigated the hypothesis that cell autonomous Men1 inactivation in glial fibrillary acidic protein (GFAP)-expressing cells induced neuroendocrine differentiation and tumorigenesis. METHODS Transgenic GFAPΔMen1 mice were generated by conditional GFAP-directed Men1 deletion in GFAP-expressing cells. Cre specificity was confirmed using a tdTomato reporter. GFAPΔMen1 mice were evaluated for GEP-NEN development and neuroendocrine cell hyperplasia. Small interfering RNA-mediated Men1 silencing in a rat enteric glial cell line was performed in parallel. RESULTS GFAPΔMen1 mice developed pancreatic NENs, in addition to pituitary prolactinomas that phenocopied the human MEN1 syndrome. GFAPΔMen1 mice exhibited gastric neuroendocrine hyperplasia that coincided with a significant loss of GFAP expression. Men1 deletion induced loss of glial-restricted progenitor lineage markers and an increase in neuroendocrine genes, suggesting a reprogramming of GFAP+ cells. Deleting Kif3a, a mediator of Hedgehog signaling, in GFAP-expressing cells attenuated neuroendocrine hyperplasia by restricting the neuroendocrine cell fate. Similar results in the pancreas were observed when Sox10 was used to delete Men1. CONCLUSIONS GFAP-directed Men1 inactivation exploits glial cell plasticity in favor of neuroendocrine differentiation.
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Affiliation(s)
- Suzann Duan
- University of Arizona College of Medicine, Department of Medicine, Division of Gastroenterology, Tucson, Arizona
| | - Travis W. Sawyer
- Wyant College of Optical Sciences, University of Arizona, Tucson, Arizona
| | - Ricky A. Sontz
- University of Arizona College of Medicine, Department of Medicine, Division of Gastroenterology, Tucson, Arizona
| | - Bradley A. Wieland
- University of Arizona College of Medicine, Department of Medicine, Division of Gastroenterology, Tucson, Arizona
| | - Andres F. Diaz
- University of Arizona College of Medicine, Department of Medicine, Division of Gastroenterology, Tucson, Arizona
| | - Juanita L. Merchant
- University of Arizona College of Medicine, Department of Medicine, Division of Gastroenterology, Tucson, Arizona,Correspondence Address correspondence to: Dr Juanita L. Merchant, University of Arizona, 1515 N. Campbell Ave, Tucson, AZ 85724; tel: (520) 626-7897; fax: (520) 626-1291.
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2
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Vanacker C, Defazio RA, Sykes CM, Moenter SM. A role for glial fibrillary acidic protein (GFAP)-expressing cells in the regulation of gonadotropin-releasing hormone (GnRH) but not arcuate kisspeptin neuron output in male mice. eLife 2021; 10:68205. [PMID: 34292152 PMCID: PMC8337074 DOI: 10.7554/elife.68205] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/21/2021] [Indexed: 01/05/2023] Open
Abstract
GnRH neurons are the final central neural output regulating fertility. Kisspeptin neurons in the hypothalamic arcuate nucleus (KNDy neurons) are considered the main regulator of GnRH output. GnRH and KNDy neurons are surrounded by astrocytes, which can modulate neuronal activity and communicate over distances. Prostaglandin E2 (PGE2), synthesized primarily by astrocytes, increases GnRH neuron activity and downstream pituitary release of luteinizing hormone (LH). We hypothesized that glial fibrillary acidic protein (GFAP)-expressing astrocytes play a role in regulating GnRH and/or KNDy neuron activity and LH release. We used adeno-associated viruses to target designer receptors exclusively activated by designer drugs (DREADDs) to GFAP-expressing cells to activate Gq- or Gi-mediated signaling. Activating Gq signaling in the preoptic area, near GnRH neurons, but not in the arcuate, increases LH release in vivo and GnRH firing in vitro via a mechanism in part dependent upon PGE2. These data suggest that astrocytes can activate GnRH/LH release in a manner independent of KNDy neurons.
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Affiliation(s)
- Charlotte Vanacker
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - R Anthony Defazio
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - Charlene M Sykes
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States
| | - Suzanne M Moenter
- Departments of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, United States.,Internal Medicine, University of Michigan, Ann Arbor, United States.,Obstetrics & Gynecology, University of Michigan, Ann Arbor, United States.,Reproductive Sciences Program, University of Michigan, Ann Arbor, United States
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3
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Fielitz K, Althoff K, De Preter K, Nonnekens J, Ohli J, Elges S, Hartmann W, Klöppel G, Knösel T, Schulte M, Klein-Hitpass L, Beisser D, Reis H, Eyking A, Cario E, Schulte JH, Schramm A, Schüller U. Characterization of pancreatic glucagon-producing tumors and pituitary gland tumors in transgenic mice overexpressing MYCN in hGFAP-positive cells. Oncotarget 2018; 7:74415-74426. [PMID: 27769070 PMCID: PMC5342675 DOI: 10.18632/oncotarget.12766] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 10/13/2016] [Indexed: 01/28/2023] Open
Abstract
Amplification or overexpression of MYCN is involved in development and maintenance of multiple malignancies. A subset of these tumors originates from neural precursors, including the most aggressive forms of the childhood tumors, neuroblastoma and medulloblastoma. In order to model the spectrum of MYCN-driven neoplasms in mice, we transgenically overexpressed MYCN under the control of the human GFAP-promoter that, among other targets, drives expression in neural progenitor cells. However, LSL-MYCN;hGFAP-Cre double transgenic mice did neither develop neural crest tumors nor tumors of the central nervous system, but presented with neuroendocrine tumors of the pancreas and, less frequently, the pituitary gland. Pituitary tumors expressed chromogranin A and closely resembled human pituitary adenomas. Pancreatic tumors strongly produced and secreted glucagon, suggesting that they derived from glucagon- and GFAP-positive islet cells. Interestingly, 3 out of 9 human pancreatic neuroendocrine tumors expressed MYCN, supporting the similarity of the mouse tumors to the human system. Serial transplantations of mouse tumor cells into immunocompromised mice confirmed their fully transformed phenotype. MYCN-directed treatment by AuroraA- or Brd4-inhibitors resulted in significantly decreased cell proliferation in vitro and reduced tumor growth in vivo. In summary, we provide a novel mouse model for neuroendocrine tumors of the pancreas and pituitary gland that is dependent on MYCN expression and that may help to evaluate MYCN-directed therapies.
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Affiliation(s)
- Kathrin Fielitz
- Department of Pediatric Oncology and Hematology, University Children's Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Kristina Althoff
- Department of Pediatric Oncology and Hematology, University Children's Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Katleen De Preter
- Centre for Medical Genetics, Ghent University Hospital, Ghent, Belgium
| | - Julie Nonnekens
- Genetics and Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jasmin Ohli
- Center for Neuropathology, Ludwig-Maximilians University, Munich, Germany
| | - Sandra Elges
- Department of Pathology, University Hospital, Münster, Germany
| | | | - Günter Klöppel
- Department of Pathology, Technical University, Munich, Germany
| | - Thomas Knösel
- Department of Pathology, Ludwig-Maximilians University, Munich, Germany
| | - Marc Schulte
- Department of Pediatric Oncology and Hematology, University Children's Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ludger Klein-Hitpass
- Cell Biology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Daniela Beisser
- Genome Informatics, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Henning Reis
- Department of Pathology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Annette Eyking
- Division of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Elke Cario
- Division of Gastroenterology and Hepatology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Johannes H Schulte
- Department of Pediatric Oncology and Hematology, Charité University Medicine, Berlin, Germany
| | - Alexander Schramm
- Department of Pediatric Oncology and Hematology, University Children's Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ulrich Schüller
- Center for Neuropathology, Ludwig-Maximilians University, Munich, Germany.,Institute of Neuropathology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany.,Research Institute Childrens Cancer Center, Hamburg, Germany.,Department of Pediatric Oncology and Hematology, University Medical Center, Hamburg-Eppendorf, Hamburg, Germany
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4
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Hashimoto A, Karim MR, Izawa T, Kuwamura M, Yamate J. Immunophenotypical analysis of pancreatic interstitial cells in the developing rat pancreas and myofibroblasts in the fibrotic pancreas in dogs and cats. J Vet Med Sci 2017; 79:1920-1926. [PMID: 29046498 PMCID: PMC5745165 DOI: 10.1292/jvms.17-0423] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Pancreatic fibrosis develops as the results of the activity of myofibroblasts capable of
producing collagens. The myofibroblasts derive from pancreatic interstitial cells,
including pancreatic stellate cells (PSCs), which can express glial fibrillary acidic
protein (GFAP). First, we investigated the expression patterns of vimentin, desmin,
α-smooth muscle actin (α-SMA), Thy-1 and GFAP in the developing rat pancreas (in fetuses
at 18 and 20 days, neonates from 1 to 21 days, and adults). Interstitial cells in the
developing pancreas expressed vimentin, desmin, GFAP and Thy-1 at varying degrees;
interestingly, the reactivity for desmin and vimentin was the highest in fetuses. GFAP
expression was consistent between fetuses and neonates, and Thy-1 reactivity transiently
increased after birth; however, α-SMA-positive interstitial cells were rarely seen. Next,
we analyzed the immunophenotypical characteristics of myofibroblasts appearing in
pancreatic fibrosis in dogs and cats. With increasing fibrotic grade, myofibroblasts
showed increased expression of vimentin, desmin and α-SMA, in addition to increased GFAP
expression. Collectively, pancreatic interstitial cells and myofibroblasts may have
similar immunophenotypes, and myofibroblasts might originate partly from GFAP-expressing
PSCs.
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Affiliation(s)
- Ai Hashimoto
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano-shi, Osaka 598-8531, Japan
| | - Mohammad Rabiul Karim
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano-shi, Osaka 598-8531, Japan
| | - Takeshi Izawa
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano-shi, Osaka 598-8531, Japan
| | - Mitsuru Kuwamura
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano-shi, Osaka 598-8531, Japan
| | - Jyoji Yamate
- Laboratory of Veterinary Pathology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-58 Rinku-Ourai-Kita, Izumisano-shi, Osaka 598-8531, Japan
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5
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Pang Z, Kushiyama A, Sun J, Kikuchi T, Yamazaki H, Iwamoto Y, Koriyama H, Yoshida S, Shimamura M, Higuchi M, Kawano T, Takami Y, Rakugi H, Morishita R, Nakagami H. Glial fibrillary acidic protein (GFAP) is a novel biomarker for the prediction of autoimmune diabetes. FASEB J 2017; 31:4053-4063. [PMID: 28546444 DOI: 10.1096/fj.201700110r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 05/08/2017] [Indexed: 11/11/2022]
Abstract
Glial fibrillary acidic protein (GFAP) is expressed in peri-islet Schwann cells, as well as in glia cells, and has been reported to be an autoantigen candidate for type 1 diabetes mellitus (T1DM). We confirmed that the production of the autoantibodies GFAP and glutamic acid decarboxylase 65 (GAD65) was increased and inversely correlated with the concentration of secreted C peptide in female nonobese diabetic mice (T1DM model). Importantly, the development of T1DM in female nonobese diabetic mice at 30 wk of age was predicted by the positive GFAP autoantibody titer at 17 wk. The production of GFAP and GAD65 autoantibodies was also increased in KK-Ay mice [type 2 diabetes mellitus (T2DM) model]. In patients with diabetes mellitus, GFAP autoantibody levels were increased in patients with either T1DM or T2DM, and were significantly associated with GAD65 autoantibodies but not zinc transporter 8 autoantibodies. Furthermore, we identified a B-cell epitope of GFAP corresponding to the GFAP autoantibody in both mice and patients with diabetes. Thus, these results indicate that autoantibodies against GFAP could serve as a predictive marker for the development of overt autoimmune diabetes.-Pang, Z., Kushiyama, A., Sun, J., Kikuchi, T., Yamazaki, H., Iwamoto, Y., Koriyama, H., Yoshida, S., Shimamura, M., Higuchi, M., Kawano, T., Takami, Y., Rakugi, H., Morishita, R., Nakagumi, H. Glial fibrillary acidic protein (GFAP) is a novel biomarker for the prediction of autoimmune diabetes.
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Affiliation(s)
- Zhengda Pang
- Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, Xi'an, China.,Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Akifumi Kushiyama
- Division of Diabetes and Metabolism, The Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan
| | - Jiao Sun
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Takako Kikuchi
- Division of Diabetes and Metabolism, The Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan
| | - Hiroki Yamazaki
- Division of Diabetes and Metabolism, The Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan
| | - Yasuhiko Iwamoto
- Division of Diabetes and Metabolism, The Institute for Adult Diseases, Asahi Life Foundation, Tokyo, Japan
| | - Hiroshi Koriyama
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Shota Yoshida
- Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Munehisa Shimamura
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Masayoshi Higuchi
- Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomohiro Kawano
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan; and
| | - Yoichi Takami
- Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hiromi Rakugi
- Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Ryuichi Morishita
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hironori Nakagami
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Osaka, Japan;
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6
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Pang Z, Higuchi M, Koriyama H, Yoshida S, Kurinami H, Shimamura M, Takami Y, Rakugi H, Morishita R, Nakagami H. Evaluating the potential of the GFAP-KLH immune-tolerizing vaccine for type 1 diabetes in mice. FEBS Lett 2016; 591:129-136. [PMID: 27926781 DOI: 10.1002/1873-3468.12511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 10/20/2016] [Accepted: 11/28/2016] [Indexed: 12/16/2022]
Abstract
Glial fibrillary acidic protein (GFAP), expressed in peri-islet Schwann cells, is a novel target for the treatment of type 1 diabetes mellitus (T1DM). We designed a GFAP immune-tolerizing vaccine that successfully suppresses hyperglycemia and enhances C peptide secretion. The GFAP vaccine significantly prevented T cell infiltration into pancreatic islets. Moreover, after GFAP vaccination, naïve T-cell differentiation shifted from a cytotoxic Th1- to a Th2-biased humoral response. These results indicate that as a novel target, GFAP reliably predicts the development of T1DM, and that the GFAP vaccine successfully delays the progression of T1DM by regulating T-cell differentiation.
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Affiliation(s)
- Zhengda Pang
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Japan.,Department of Physiology and Pathophysiology, School of Medicine, Xi'an Jiaotong University, China
| | - Masayoshi Higuchi
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Japan
| | - Hiroshi Koriyama
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Japan
| | - Shota Yoshida
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Japan
| | - Hitomi Kurinami
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Japan
| | - Munehisa Shimamura
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Japan
| | - Yoichi Takami
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Japan
| | - Hiromi Rakugi
- Department of Geriatric and General Medicine, Osaka University Graduate School of Medicine, Japan
| | - Ryuichi Morishita
- Department of Clinical Gene Therapy, Osaka University Graduate School of Medicine, Japan
| | - Hironori Nakagami
- Department of Health Development and Medicine, Osaka University Graduate School of Medicine, Japan
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7
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Machida M, Fujimaki S, Hidaka R, Asashima M, Kuwabara T. The insulin regulatory network in adult hippocampus and pancreatic endocrine system. Stem Cells Int 2012; 2012:959737. [PMID: 22988465 PMCID: PMC3440949 DOI: 10.1155/2012/959737] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 08/06/2012] [Accepted: 08/09/2012] [Indexed: 12/19/2022] Open
Abstract
There is a very strong correlation between the insulin-mediated regulatory system of the central nervous system and the pancreatic endocrine system. There are many examples of the same transcriptional factors being expressed in both regions in their embryonic development stages. Hormonal signals from the pancreatic islets influence the regulation of energy homeostasis by the brain, and the brain in turn influences the secretions of the islets. Diabetes induces neuronal death in different regions of the brain especially hippocampus, causes alterations on the neuronal circuits and therefore impairs learning and memory, for which the hippocampus is responsible. The hippocampus is a region of the brain where steady neurogenesis continues throughout life. Adult neurogenesis from undifferentiated neural stem cells is greatly decreased in diabetic patients, and as a result their learning and memory functions decline. Might it be possible to reactivate stem cells whose functions have deteriorated and that are present in the tissues in which the lesions occur in diabetes, a lifestyle disease, which plagues modern humans and develops as a result of the behavior of insulin-related factor? In this paper we summarize research in regard to these matters based on examples in recent years.
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Affiliation(s)
| | | | | | | | - Tomoko Kuwabara
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, 1-1-4 Higashi, Tsukuba Science City 305-8562, Japan
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8
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Ding Z, Maubach G, Masamune A, Zhuo L. Glial fibrillary acidic protein promoter targets pancreatic stellate cells. Dig Liver Dis 2009; 41:229-36. [PMID: 18602878 DOI: 10.1016/j.dld.2008.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2008] [Revised: 04/25/2008] [Accepted: 05/05/2008] [Indexed: 12/11/2022]
Abstract
BACKGROUND Pancreatic fibrosis is one of the clinical manifestations of chronic pancreatitis and pancreatic cancer. Pancreatic stellate cells (PSCs) have been recognised as principal effector cells in the development of pancreatic fibrosis. The ability to specifically address PSCs might offer a potential for developing a targeted therapy for pancreatic fibrosis. AIM Characterisation of the 2.2kb hGFAP (human glial fibrillary acidic protein) promoter for its usefulness to express reporter genes specifically in PSCs in vitro and in vivo. METHODS 2.2kb hGFAP-LacZ reporter expressions were examined in four immortalised PSC lines and two non-PSCs, meanwhile, GFAP-LacZ transgenic mice were used to detect LacZ reporter in pancreas tissue. Several kinase inhibitors, vitamin A and its metabolites were applied to study the regulation of 2.2kb hGFAP promoter in PSCs. RESULTS Our results showed that the 2.2kb hGFAP promoter is capable of regulating the expression of reporter genes exclusively in immortalised and primary PSCs, as well as in PSCs of transgenic GFAP-LacZ mice. When a PSC cell line transfected with the LacZ reporter (SAM-K/LacZ/C1) was treated with different anti-fibrotic agents and kinase inhibitors, the transgenic beta-galactosidase activity was found to be regulated by multiple signalling pathways known to be involved in the PSC activation. CONCLUSIONS This study provides the proof of concept for using the 2.2kb hGFAP promoter to specifically manipulate PSCs for the development of targeted gene and/or drug therapy in pancreatic fibrosis, and for the screening of anti-fibrotic agents.
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Affiliation(s)
- Z Ding
- Institute of Bioengineering and Nanotechnology, Singapore
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9
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Imura T, Nakano I, Kornblum HI, Sofroniew MV. Phenotypic and functional heterogeneity of GFAP-expressing cells in vitro: differential expression of LeX/CD15 by GFAP-expressing multipotent neural stem cells and non-neurogenic astrocytes. Glia 2006; 53:277-93. [PMID: 16267834 DOI: 10.1002/glia.20281] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Recent findings show that the predominant multipotent neural stem cells (NSCs) isolated from postnatal and adult mouse brain express glial fibrillary acid protein (GFAP), a protein commonly associated with astrocytes, and that primary astrocyte cultures can contain GFAP-expressing cells that act as multipotent NSCs when transferred to neurogenic conditions. The relationship of GFAP-expressing NSCs to GFAP-expressing astrocytes is unclear, but has important implications. We compared the phenotype and neurogenic potential of GFAP-expressing cells derived from different CNS regions and maintained in vitro under different conditions. Multiple labeling immunohistochemistry revealed that both primary astrocyte cultures and adherent neurogenic cultures derived from postnatal or adult periventricular tissue contained subpopulations of GFAP-expressing cells that co-expressed nestin and LeX/CD15, two molecules associated with NSCs. In contrast, GFAP-expressing cells in similar cultures prepared from adult cerebral cortex did not express detectable levels of LeX/CD15, and exhibited no neurogenic potential. Fluorescence-activated cell sorting (FACS) of both primary astrocyte cultures and adherent neurogenic cultures for LeX/CD15 showed that GFAP-expressing cells competent to act as multipotent NSCs were concentrated in the LeX-positive fraction. Using neurosphere assays and a transgenic ablation strategy, we confirmed that the predominant NSCs in primary astrocyte and adherent neurogenic cultures were GFAP-expressing cells. These findings demonstrate that GFAP-expressing cells derived from postnatal and adult forebrain are heterogeneous in both molecular phenotype and neurogenic potential in vitro, and that this heterogeneity exists before exposure to neurogenic conditions. The findings provide evidence that GFAP-expressing NSCs are phenotypically and functionally distinct from non-neurogenic astrocytes.
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Affiliation(s)
- Tetsuya Imura
- Department of Neurobiology, University of California, Los Angeles, California 90095-1763, USA
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10
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Bertelli E, Regoli M, Gambelli F, Lucattelli M, Lungarella G, Bastianini A. GFAP is expressed as a major soluble pool associated with glucagon secretory granules in A-cells of mouse pancreas. J Histochem Cytochem 2000; 48:1233-42. [PMID: 10950880 DOI: 10.1177/002215540004800907] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
To elucidate the role of intermediate filament proteins in endocrine cells, we investigated the expression and subcellular distribution of GFAP in mouse islets of Langerhans. For this purpose, combined immunocytochemical and biochemical analysis with a panel of antibodies was carried out to identify GFAP-immunoreactive cells in mouse endocrine pancreas. Cell fractionation into NP-40-soluble and detergent/high salt-insoluble components was performed to assess whether GFAP was located in the cytosolic and/or cytoskeletal compartments of immunoreactive cells. Immunoelectron microscopic analysis was carried out to determine the subcellular distribution of the protein. Peripheral islet cells were stained with anti-GFAP antiserum. These cells were identified as glucagon-secreting cells by immunocytochemical staining of consecutive sections with anti-somatostatin, anti-GFAP, and anti-glucagon antisera. Western blotting analysis of both NP-40-soluble and detergent/high-salt insoluble fractions of isolated islets of Langerhans allowed detection of GFAP in both cytosolic and cytoskeletal compartments. Interestingly, however, the former location was highly predominant. In addition, immunoelectron microscopy localized GFAP associated with the periphery of secretory granules. On the basis of these results, an intriguing role for GFAP in secretory events should be strongly suspected.(J Histochem Cytochem 48:1233-1242, 2000)
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Affiliation(s)
- E Bertelli
- Department of Biomedical Sciences, University of Siena, Siena, Italy
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