1
|
Kirchenwitz M, Stahnke S, Prettin S, Borowiak M, Menke L, Sieben C, Birchmeier C, Rottner K, Stradal TEB, Steffen A. SMER28 Attenuates PI3K/mTOR Signaling by Direct Inhibition of PI3K p110 Delta. Cells 2022; 11:cells11101648. [PMID: 35626685 PMCID: PMC9140127 DOI: 10.3390/cells11101648] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/03/2022] [Accepted: 05/12/2022] [Indexed: 02/06/2023] Open
Abstract
SMER28 (Small molecule enhancer of Rapamycin 28) is an autophagy-inducing compound functioning by a hitherto unknown mechanism. Here, we confirm its autophagy-inducing effect by assessing classical autophagy-related parameters. Interestingly, we also discovered several additional effects of SMER28, including growth retardation and reduced G1 to S phase progression. Most strikingly, SMER28 treatment led to a complete arrest of receptor tyrosine kinase signaling, and, consequently, growth factor-induced cell scattering and dorsal ruffle formation. This coincided with a dramatic reduction in phosphorylation patterns of PI3K downstream effectors. Consistently, SMER28 directly inhibited PI3Kδ and to a lesser extent p110γ. The biological relevance of our observations was underscored by SMER28 interfering with InlB-mediated host cell entry of Listeria monocytogenes, which requires signaling through the prominent receptor tyrosine kinase c-Met. This effect was signaling-specific, since entry of unrelated, gram-negative Salmonella Typhimurium was not inhibited. Lastly, in B cell lymphoma cells, which predominantly depend on tonic signaling through PI3Kδ, apoptosis upon SMER28 treatment is profound in comparison to non-hematopoietic cells. This indicates SMER28 as a possible drug candidate for the treatment of diseases that derive from aberrant PI3Kδ activity.
Collapse
Affiliation(s)
- Marco Kirchenwitz
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Stephanie Stahnke
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
| | - Silvia Prettin
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
| | - Malgorzata Borowiak
- Developmental Biology/Signal Transduction, Max Delbrueck Center for Molecular Medicine, 13125 Berlin, Germany; (M.B.); (C.B.)
| | - Laura Menke
- Nanoscale Infection Biology Group, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (L.M.); (C.S.)
| | - Christian Sieben
- Nanoscale Infection Biology Group, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (L.M.); (C.S.)
| | - Carmen Birchmeier
- Developmental Biology/Signal Transduction, Max Delbrueck Center for Molecular Medicine, 13125 Berlin, Germany; (M.B.); (C.B.)
| | - Klemens Rottner
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany
| | - Theresia E. B. Stradal
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
- Correspondence: (T.E.B.S.); (A.S.); Tel.: +49-531-6181-2900 (T.E.B.S.); +49-531-6181-2902 (A.S.)
| | - Anika Steffen
- Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; (M.K.); (S.S.); (S.P.); (K.R.)
- Correspondence: (T.E.B.S.); (A.S.); Tel.: +49-531-6181-2900 (T.E.B.S.); +49-531-6181-2902 (A.S.)
| |
Collapse
|
2
|
Seridi N, Hamidouche M, Belmessabih N, El Kennani S, Gagnon J, Martinez G, Coutton C, Marchal T, Chebloune Y. Immortalization of primary sheep embryo kidney cells. In Vitro Cell Dev Biol Anim 2021; 57:76-85. [PMID: 33415664 DOI: 10.1007/s11626-020-00520-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 10/13/2020] [Indexed: 10/22/2022]
Abstract
Sheep primary epithelial cells are short-lived in cell culture systems. For long-term in vitro studies, primary cells need to be immortalized. This study aims to establish and characterize T immortalized sheep embryo kidney cells (TISEKC). In this study, we used fetal lamb kidneys to derive primary cultures of epithelial cells. We subsequently immortalized these cells using the large T SV40 antigen to generate crude TISEKC and isolate TISEKC clones. Among numerous clones of immortalized cells, the selected TISEKC-5 maintained active division and cell growth over 20 passages but lacked expression of the oncogenic large T SV40 antigen. Morphologically, TISEKC-5 maintained their epithelial aspect similar to the parental primary epithelial cells. However, their growth properties showed quite different patterns. Crude TISEKC, as well as the clones of TISEKC proliferated highly in culture compared to the parental primary cells. In the early passages, immortalized cells showed heterogeneous polyploidy but in the late passages the karyotype of immortalized cells became progressively stable, identical to that of the primary cells, because the TISEKC-5 cell line has lost the large SV40 T antigen expression, this cell line is a valuable tool for veterinary sciences and biotechnological productions.
Collapse
Affiliation(s)
- N Seridi
- Laboratory of Molecular and Cellular Biology, Unit of Genetics, Faculty of Biological Sciences, University of Sciences and Technology "Houari Boumediene", Algiers, Algeria
| | - M Hamidouche
- Laboratory of Production and Development of Viral Veterinary Vaccines, Pasteur Institute of Algeria, Algiers, Algeria
| | - N Belmessabih
- Laboratory of Production and Development of Viral Veterinary Vaccines, Pasteur Institute of Algeria, Algiers, Algeria
| | - S El Kennani
- INRAE/UGA USC 1450, Pathogenesis and Lentivirus Vaccination Laboratory, PAVAL Lab, Université Grenoble Alpes, 38041, Grenoble Cedex 9, France
| | - J Gagnon
- INRAE/UGA USC 1450, Pathogenesis and Lentivirus Vaccination Laboratory, PAVAL Lab, Université Grenoble Alpes, 38041, Grenoble Cedex 9, France
| | - G Martinez
- CHU Grenoble Alpes, UM de Génétique Chromosomique, Grenoble, France.,INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Université Grenoble Alpes, 38000, Grenoble, France
| | - C Coutton
- CHU Grenoble Alpes, UM de Génétique Chromosomique, Grenoble, France.,INSERM U1209, CNRS UMR 5309, Institute for Advanced Biosciences, Université Grenoble Alpes, 38000, Grenoble, France
| | - T Marchal
- VetAgro Sup, UPSP ICE 2011.03.101, Laboratoire d'Histopathologie, Université de Lyon, Marcy-l'Etoile, France
| | - Y Chebloune
- INRAE/UGA USC 1450, Pathogenesis and Lentivirus Vaccination Laboratory, PAVAL Lab, Université Grenoble Alpes, 38041, Grenoble Cedex 9, France.
| |
Collapse
|
3
|
Agarwal S, Sudhini YR, Reiser J, Altintas MM. From Infancy to Fancy: A Glimpse into the Evolutionary Journey of Podocytes in Culture. KIDNEY360 2020; 2:385-397. [PMID: 35373019 PMCID: PMC8740988 DOI: 10.34067/kid.0006492020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 12/22/2020] [Indexed: 02/04/2023]
Abstract
Podocytes are critical components of the filtration barrier and responsible for maintaining healthy kidney function. An assault on podocytes is generally associated with progression of chronic glomerular diseases. Therefore, podocyte pathophysiology is a favorite research subject for nephrologists. Despite this, podocyte research has lagged because of the unavailability of techniques for culturing such specialized cells ex vivo in quantities that are adequate for mechanistic studies. In recent years, this problem was circumvented by the efforts of researchers, who successfully developed several in vitro podocyte cell culture model systems that paved the way for incredible discoveries in the field of nephrology. This review sets us on a journey that provides a comprehensive insight into the groundbreaking breakthroughs and novel technologic advances made in the field of podocyte cell culture so far, beginning from its inception, evolution, and progression. In this study, we also describe in detail the pros and cons of different models that are being used to culture podocytes. Our extensive and exhaustive deliberation on the status of podocyte cell culture will facilitate researchers to choose wisely an appropriate model for their own research to avoid potential pitfalls in the future.
Collapse
|
4
|
Egaña-Gorroño L, Chinnasamy P, Casimiro I, Almonte VM, Parikh D, Oliveira-Paula GH, Jayakumar S, Law C, Riascos-Bernal DF, Sibinga NES. Allograft inflammatory factor-1 supports macrophage survival and efferocytosis and limits necrosis in atherosclerotic plaques. Atherosclerosis 2019; 289:184-194. [PMID: 31439353 DOI: 10.1016/j.atherosclerosis.2019.07.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 07/12/2019] [Accepted: 07/24/2019] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND AIMS Allograft inflammatory factor-1 (AIF1) has been characterized as a pro-inflammatory molecule expressed primarily in the monocyte/macrophage (MP) lineage and positively associated with various forms of vascular disease, including atherosclerosis. Studies of AIF1 in atherosclerosis have relied on mouse models in which AIF1 was overexpressed in either myeloid or smooth muscle cells, resulting in increased atherosclerotic plaque burden. How physiologic expression of AIF1 contributes to MP biology in atherogenesis is not known. METHODS Effects of global AIF1 deficiency on atherosclerosis were assessed by crossing Aif1-/- and ApoE-/- mice, and provoking hyperlipidemia with high fat diet feeding. Atherosclerotic plaques were studied en face and in cross section. Bone marrow-derived MPs (BMDMs) were isolated from Aif1-/- mice for study in culture. RESULTS Atherosclerotic plaques in Aif1-/-;ApoE-/- mice showed larger necrotic cores compared to those in ApoE-/- animals, without change in overall lesion burden. In vitro, lack of AIF1 reduced BMDM survival, phagocytosis, and efferocytosis. Mechanistically, AIF1 supported activation of the NF-κB pathway and expression of related target genes involved in stress response, inflammation, and apoptosis. Consistent with this in vitro BMDM phenotype, AIF1 deficiency reduced NF-κB pathway activity in vivo and increased apoptotic cell number in atherosclerotic lesions from Aif1-/-;ApoE-/- mice. CONCLUSIONS These findings characterize AIF1 as a positive regulator of the NF-κB pathway that supports MP functions such as survival and efferocytosis. In inflammatory settings such as atherosclerosis, these AIF1-dependent activities serve to clear cellular and other debris and limit necrotic core expansion, and may oppose lesion destabilization.
Collapse
Affiliation(s)
- Lander Egaña-Gorroño
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Prameladevi Chinnasamy
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Isabel Casimiro
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Vanessa M Almonte
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Dippal Parikh
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Gustavo H Oliveira-Paula
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Smitha Jayakumar
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Calvin Law
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Dario F Riascos-Bernal
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA
| | - Nicholas E S Sibinga
- Albert Einstein College of Medicine, Wilf Family Cardiovascular Research Institute, Department of Medicine (Cardiology) and Department of Developmental and Molecular Biology, 1300 Morris Park Avenue, Bronx, NY, 10461, USA.
| |
Collapse
|
5
|
The metabolic/pH sensor soluble adenylyl cyclase is a tumor suppressor protein. Oncotarget 2018; 7:45597-45607. [PMID: 27323809 PMCID: PMC5216745 DOI: 10.18632/oncotarget.10056] [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: 01/15/2016] [Accepted: 06/01/2016] [Indexed: 11/25/2022] Open
Abstract
cAMP signaling pathways can both stimulate and inhibit the development of cancer; however, the sources of cAMP important for tumorigenesis remain poorly understood. Soluble adenylyl cyclase (sAC) is a non-canonical, evolutionarily conserved, nutrient- and pH-sensing source of cAMP. sAC has been implicated in the metastatic potential of certain cancers, and it is differentially localized in human cancers as compared to benign tissues. We now show that sAC expression is reduced in many human cancers. Loss of sAC increases cellular transformation in vitro and malignant progression in vivo. These data identify the metabolic/pH sensor soluble adenylyl cyclase as a previously unappreciated tumor suppressor protein.
Collapse
|
6
|
Establishment of a Conditionally Immortalized Wilms Tumor Cell Line with a Homozygous WT1 Deletion within a Heterozygous 11p13 Deletion and UPD Limited to 11p15. PLoS One 2016; 11:e0155561. [PMID: 27213811 PMCID: PMC4876997 DOI: 10.1371/journal.pone.0155561] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 04/29/2016] [Indexed: 01/27/2023] Open
Abstract
We describe a stromal predominant Wilms tumor with focal anaplasia and a complex, tumor specific chromosome 11 aberration: a homozygous deletion of the entire WT1 gene within a heterozygous 11p13 deletion and an additional region of uniparental disomy (UPD) limited to 11p15.5-p15.2 including the IGF2 gene. The tumor carried a heterozygous p.T41A mutation in CTNNB1. Cells established from the tumor carried the same chromosome 11 aberration, but a different, homozygous p.S45Δ CTNNB1 mutation. Uniparental disomy (UPD) 3p21.3pter lead to the homozygous CTNNB1 mutation. The tumor cell line was immortalized using the catalytic subunit of human telomerase (hTERT) in conjunction with a novel thermolabile mutant (U19dl89-97tsA58) of SV40 large T antigen (LT). This cell line is cytogenetically stable and can be grown indefinitely representing a valuable tool to study the effect of a complete lack of WT1 in tumor cells. The origin/fate of Wilms tumors with WT1 mutations is currently poorly defined. Here we studied the expression of several genes expressed in early kidney development, e.g. FOXD1, PAX3, SIX1, OSR1, OSR2 and MEIS1 and show that these are expressed at similar levels in the parental and the immortalized Wilms10 cells. In addition the limited potential for muscle/ osteogenic/ adipogenic differentiation similar to all other WT1 mutant cell lines is also observed in the Wilms10 tumor cell line and this is retained in the immortalized cells. In summary these Wilms10 cells are a valuable model system for functional studies of WT1 mutant cells.
Collapse
|
7
|
Tabuchi Y, Wada S, Ikegame M, Kariya A, Furusawa Y, Hoshi N, Yunoki T, Suzuki N, Takasaki I, Kondo T, Suzuki Y. Development of oral epithelial cell line ROE2 with differentiation potential from transgenic rats harboring temperature-sensitive simian virus40 large T-antigen gene. Exp Anim 2014; 63:31-44. [PMID: 24521861 PMCID: PMC4160936 DOI: 10.1538/expanim.63.31] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
We have developed an immortalized oral epithelial cell line, ROE2, from fetal transgenic
rats harboring temperature-sensitive simian virus 40 large T-antigen gene. The cells grew
continuously at either a permissive temperature of 33°C or an intermediate temperature of
37°C. At the nonpermissive temperature of 39°C, on the other hand, growth decreased
significantly, and the Sub-G1 phase of the cell cycle increased, indicating that the cells
undergo apoptosis at a nonpermissive temperature. Histological and immunocytochemical
analyses revealed that ROE2 cells at 37°C had a stratified epithelial-like morphology and
expressed cytokeratins Krt4 and Krt13, marker proteins for oral nonkeratinized epithelial
cells. Global-scale comprehensive microarray analysis, coupled with bioinformatics tools,
demonstrated a significant gene network that was obtained from the upregulated genes. The
gene network contained 16 genes, including Cdkn1a, Fos,
Krt13, and Prdm1, and was associated mainly with the
biological process of skin development in the category of biological functions, organ
development. These four genes were validated by quantitative real-time polymerase chain
reaction, and the results were nearly consistent with the microarray data. It is therefore
anticipated that this cell line will be useful as an in vitro model for
studies such as physiological functions, as well as for gene expression in oral epithelial
cells.
Collapse
Affiliation(s)
- Yoshiaki Tabuchi
- Division of Molecular Genetics Research, Life Science Research Center, University of Toyama, 2630 Sugitani, Toyama 930-0194, Japan
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Langert KA, Von Zee CL, Stubbs EB. Cdc42 GTPases facilitate TNF-α-mediated secretion of CCL2 from peripheral nerve microvascular endoneurial endothelial cells. J Peripher Nerv Syst 2014; 18:199-208. [PMID: 24028188 DOI: 10.1111/jns5.12032] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 05/01/2013] [Accepted: 07/22/2013] [Indexed: 12/31/2022]
Abstract
Trafficking of autoreactive leukocytes across the blood-nerve barrier and into peripheral nerves is an early pathological hallmark of Guillain-Barré syndrome (GBS). Tumor necrosis factor-α (TNF-α), a proinflammatory cytokine, promotes transendothelial migration by upregulating endothelial expression of inflammatory mediators, including CCL2, a chemokine implicated in GBS. We sought to determine the mechanism by which TNF-α induces expression and secretion of CCL2 from peripheral nerve microvascular endoneurial endothelial cells (PNMECs). Expression of CCL2 mRNA and protein in quiescent PNMEC cultures was minimal. In contrast, cultures treated with TNF-α exhibited increased CCL2 mRNA and protein content, as well as protein secretion. Simvastatin significantly attenuated TNF-α-induced CCL2 secretion without affecting CCL2 mRNA or protein expression. Co-incubation with geranylgeranyl pyrophosphate, but not farnesyl pyrophosphate, prevented the effect of simvastatin. By comparison, inhibiting protein isoprenylation with GGTI-298, but not FTI-277, mimicked the effect of simvastatin and significantly attenuated transendothelial migration in vitro. Inhibition of the monomeric GTPase Cdc42, but not Rac1 or RhoA-C, attenuated TNF-α-mediated CCL2 secretion. TNF-α-mediated trafficking of autoreactive leukocytes into peripheral nerves during GBS may proceed by a mechanism that involves Cdc42-facilitated secretion of CCL2.
Collapse
Affiliation(s)
- Kelly A Langert
- Research Service, Department of Veterans Affairs, Edward Hines, Jr. VA Hospital, Hines, IL, USA; Program of Neuroscience
| | | | | |
Collapse
|
9
|
Moik D, Böttcher A, Makhina T, Grashoff C, Bulus N, Zent R, Fässler R. Mutations in the paxillin-binding site of integrin-linked kinase (ILK) destabilize the pseudokinase domain and cause embryonic lethality in mice. J Biol Chem 2013; 288:18863-71. [PMID: 23658024 DOI: 10.1074/jbc.m113.470476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Integrin-linked kinase (ILK) localizes to focal adhesions (FAs) where it regulates cell spreading, migration, and growth factor receptor signaling. Previous reports showed that overexpressed ILK in which Val(386) and Thr(387) were substituted with glycine residues (ILK-VT/GG) could neither interact with paxillin nor localize to FA in cells expressing endogenous wild-type ILK, implying that paxillin binding to ILK is required for its localization to FAs. Here, we show that introducing this mutation into the germ line of mice (ILK-VT/GG) caused vasculogenesis defects, resulting in a general developmental delay and death at around embryonic day 12.5. Fibroblasts isolated from ILK-VT/GG mice contained mutant ILK in FAs, showed normal adhesion to and spreading on extracellular matrix substrates but displayed impaired migration. Biochemical analysis revealed that VT/GG substitutions decreased ILK protein stability leading to decreased ILK levels and reduced binding to paxillin and α-parvin. Because paxillin depletion did not affect ILK localization to FAs, the embryonic lethality and the in vitro migration defects are likely due to the reduced levels of ILK-VT/GG and diminished binding to parvins.
Collapse
Affiliation(s)
- Daniel Moik
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | | | | | | | | | | | | |
Collapse
|
10
|
Istvanffy R, Oostendorp RAJ. Generation and establishment of murine adherent cell lines. Methods Mol Biol 2013. [PMID: 23179840 DOI: 10.1007/978-1-62703-128-8_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We describe a method to derive cell lines and clones from cells of the murine midgestation aorta-gonads-mesonephros (AGM) microenvironment. We start from subdissected AGM regions in "explant" or "single cell suspension" type cultures from embryos transgenic for tsA58, a temperature-sensitive mutant of the SV40 T antigen gene. The number of cells in such cultures initially expand, but in most cases, this expansion phase is followed by a stable or even decline in cell number. After this so-called crisis phase, cell proliferation is noticeable in more than 90% of the cultures. Stromal cell clones can be isolated from these cultures, some of which have been cultured for more than 50 population doublings, and functionally characterized using various methods These stromal cell clones are valuable tools for the study of the regulation of hematopoietic stem and progenitor cells in the midgestation mouse embryo.
Collapse
Affiliation(s)
- Rouzanna Istvanffy
- The Stem Cell Physiology Laboratory, Medizinische Klinik, Technische Universität München, Munich, Germany
| | | |
Collapse
|
11
|
Tumour necrosis factor α enhances CCL2 and ICAM-1 expression in peripheral nerve microvascular endoneurial endothelial cells. ASN Neuro 2013; 5:e00104. [PMID: 23293927 PMCID: PMC3565377 DOI: 10.1042/an20120048] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Recruitment and trafficking of autoreactive leucocytes across the BNB (blood-nerve barrier) is an early pathological insult in GBS (Guillain-Barré syndrome), an aggressive autoimmune disorder of the PNS (peripheral nervous system). Whereas the aetiology and pathogenesis of GBS remain unclear, pro-inflammatory cytokines, including TNFα (tumour necrosis factor α), are reported to be elevated early in the course of GBS and may initiate nerve injury by activating the BNB. Previously, we reported that disrupting leucocyte trafficking in vivo therapeutically attenuates the course of an established animal model of GBS. Here, PNMECs (peripheral nerve microvascular endothelial cells) that form the BNB were harvested from rat sciatic nerves, immortalized by SV40 (simian virus 40) large T antigen transduction and subsequently challenged with TNFα. Relative changes in CCL2 (chemokine ligand 2) and ICAM-1 (intercellular adhesion molecule 1) expression were determined. We report that TNFα elicits marked dose- and time-dependent increases in CCL2 and ICAM-1 mRNA and protein content and promotes secretion of functional CCL2 from immortalized and primary PNMEC cultures. TNFα-mediated secretion of CCL2 promotes, in vitro, the transendothelial migration of CCR2-expressing THP-1 monocytes. Increased CCL2 and ICAM-1 expression in response to TNFα may facilitate recruitment and trafficking of autoreactive leucocytes across the BNB in autoimmune disorders, including GBS.
Collapse
|
12
|
Eaton MJ, Berrocal Y, Wolfe SQ, Widerström-Noga E. Review of the history and current status of cell-transplant approaches for the management of neuropathic pain. PAIN RESEARCH AND TREATMENT 2012; 2012:263972. [PMID: 22745903 PMCID: PMC3382629 DOI: 10.1155/2012/263972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Accepted: 04/09/2012] [Indexed: 11/18/2022]
Abstract
Treatment of sensory neuropathies, whether inherited or caused by trauma, the progress of diabetes, or other disease states, are among the most difficult problems in modern clinical practice. Cell therapy to release antinociceptive agents near the injured spinal cord would be the logical next step in the development of treatment modalities. But few clinical trials, especially for chronic pain, have tested the transplant of cells or a cell line to treat human disease. The history of the research and development of useful cell-transplant-based approaches offers an understanding of the advantages and problems associated with these technologies, but as an adjuvant or replacement for current pharmacological treatments, cell therapy is a likely near future clinical tool for improved health care.
Collapse
Affiliation(s)
- Mary J. Eaton
- Miami VA Health System Center, D806C, 1201 NW 16th Street, Miami, FL 33125, USA
| | - Yerko Berrocal
- Department of Cellular Biology and Pharmacology, Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA
| | - Stacey Q. Wolfe
- Department of Neurosurgery, Tripler Army Medical Center, 1 Jarrett White Road, Honolulu, HI 96859, USA
| | - Eva Widerström-Noga
- Miami VA Health System Center, D806C, 1201 NW 16th Street, Miami, FL 33125, USA
- The Miami Project to Cure Paralysis, Miller School of Medicine at the University of Miami, Miami, FL 33136, USA
| |
Collapse
|
13
|
Koudijs MJ, Klijn C, van der Weyden L, Kool J, ten Hoeve J, Sie D, Prasetyanti PR, Schut E, Kas S, Whipp T, Cuppen E, Wessels L, Adams DJ, Jonkers J. High-throughput semiquantitative analysis of insertional mutations in heterogeneous tumors. Genome Res 2011; 21:2181-9. [PMID: 21852388 DOI: 10.1101/gr.112763.110] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Retroviral and transposon-based insertional mutagenesis (IM) screens are widely used for cancer gene discovery in mice. Exploiting the full potential of IM screens requires methods for high-throughput sequencing and mapping of transposon and retroviral insertion sites. Current protocols are based on ligation-mediated PCR amplification of junction fragments from restriction endonuclease-digested genomic DNA, resulting in amplification biases due to uneven genomic distribution of restriction enzyme recognition sites. Consequently, sequence coverage cannot be used to assess the clonality of individual insertions. We have developed a novel method, called shear-splink, for the semiquantitative high-throughput analysis of insertional mutations. Shear-splink employs random fragmentation of genomic DNA, which reduces unwanted amplification biases. Additionally, shear-splink enables us to assess clonality of individual insertions by determining the number of unique ligation points (LPs) between the adapter and genomic DNA. This parameter serves as a semiquantitative measure of the relative clonality of individual insertions within heterogeneous tumors. Mixing experiments with clonal cell lines derived from mouse mammary tumor virus (MMTV)-induced tumors showed that shear-splink enables the semiquantitative assessment of the clonality of MMTV insertions. Further, shear-splink analysis of 16 MMTV- and 127 Sleeping Beauty (SB)-induced tumors showed enrichment for cancer-relevant insertions by exclusion of irrelevant background insertions marked by single LPs, thereby facilitating the discovery of candidate cancer genes. To fully exploit the use of the shear-splink method, we set up the Insertional Mutagenesis Database (iMDB), offering a publicly available web-based application to analyze both retroviral- and transposon-based insertional mutagenesis data.
Collapse
Affiliation(s)
- Marco J Koudijs
- Division of Molecular Biology and Cancer Systems Biology Center, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Lin9, a subunit of the mammalian DREAM complex, is essential for embryonic development, for survival of adult mice, and for tumor suppression. Mol Cell Biol 2010; 30:2896-908. [PMID: 20404087 DOI: 10.1128/mcb.00028-10] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The retinoblastoma tumor suppressor protein (pRB) and related p107 and p130 "pocket proteins" function together with the E2F transcription factors to repress gene expression during the cell cycle and development. Recent biochemical studies have identified the multisubunit DREAM pocket protein complexes in Drosophila melanogaster and Caenorhabditis elegans in regulating developmental gene repression. Although a conserved DREAM complex has also been identified in mammalian cells, its physiological function in vivo has not been determined. Here we addressed this question by targeting Lin9, a conserved core subunit of DREAM. We found that LIN9 is essential for early embryonic development and for viability of adult mice. Loss of Lin9 abolishes proliferation and leads to multiple defects in mitosis and cytokinesis because of its requirement for the expression of a large set of mitotic genes, such as Plk1, Aurora A, and Kif20a. While Lin9 heterozygous mice are healthy and normal, they are more susceptible to lung tumorigenesis induced by oncogenic c-Raf than wild-type mice. Together these experiments provide the first direct genetic evidence for the role of LIN9 in development and mitotic gene regulation and they suggest that it may function as a haploinsufficient tumor suppressor.
Collapse
|
15
|
Su LN, Little JB. Transformation and Radiosensitivity of Human Diploid Skin Fibroblasts Transfected with SV40 T-antigen Mutants Defective in RB and P53 Binding Domains. Int J Radiat Biol 2009; 62:461-8. [PMID: 1357059 DOI: 10.1080/09553009214552341] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
A series of human diploid fibroblast cell clones were developed by DNA transfection with either wild-type SV40 T-antigen (SV40 T) or T-antigen mutants defective in its various functional domains. Cell clones expressing the wild-type SV40 T were significantly radioresistant as compared with clones transfected with the neo gene only (D0 = 192 +/- 13 vs 127 +/- 19). This radioresistance persisted in post-crisis, immortalized cell lines. A series of mutants with point or deletion mutations within each functionally active domain of SV40 T were also examined for their ability to alter radiosensitivity and induce morphological transformation. Cell clones transfected with T-antigen mutants defective in nuclear localization or origin binding showed increased radioresistance similar to clones transfected with wild-type T-antigen, and expressed morphological changes characteristic of SV40 T-transfected cells. A retinoblastoma susceptibility gene (RB) binding defective mutant showed moderately increased radioresistance (D0 = 174 +/- 10). However, cell clones transfected with three different p53 binding defective mutants showed no change in radiosensitivity (D0 = 132 +/- 5) as compared with neo gene transfected controls. Transfection with T-antigen mutants defective in either the RB or p53 binding domain yielded no morphological alterations characteristic of transformation. These data suggest that the SV40 T/p53 complex may be of importance in the radioresistance phenotype.
Collapse
Affiliation(s)
- L N Su
- Laboratory of Radiobiology, Harvard School of Public Health, Boston, Massachusetts 02115
| | | |
Collapse
|
16
|
Immortalization and characterization of mouse floxed Bmp2/4 osteoblasts. Biochem Biophys Res Commun 2009; 386:89-95. [PMID: 19501574 DOI: 10.1016/j.bbrc.2009.05.144] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 05/29/2009] [Indexed: 11/20/2022]
Abstract
Generation of a floxed Bmp2/4 osteoblast cell line is a valuable tool for studying the modulatory effects of Bmp2 and Bmp4 on osteoblast differentiation as well as relevant molecular events. In this study, primary floxed Bmp2/4 mouse osteoblasts were cultured and transfected with simian virus 40 large T-antigen. Transfection was verified by polymerase chain reaction (PCR) and immunohistochemistry. To examine the characteristics of the transfected cells, morphology, proliferation and mineralization were analyzed, expression of cell-specific genes including Runx2, ATF4, Dlx3, Osx, dentin matrix protein 1, bone sialoprotein, osteopontin, osteocalcin, osteonectin and collagen type I was detected. These results show that transfected floxed Bmp2/4 osteoblasts bypassed senescence with a higher proliferation rate, but retain the genotypic and phenotypic characteristics similar to the primary cells. Thus, we for the first time demonstrate the establishment of an immortalized mouse floxed Bmp2/4 osteoblast cell line.
Collapse
|
17
|
Yu W, Chen J, Xiong Y, Pixley FJ, Dai XM, Yeung YG, Stanley ER. CSF-1 receptor structure/function in MacCsf1r-/- macrophages: regulation of proliferation, differentiation, and morphology. J Leukoc Biol 2008; 84:852-63. [PMID: 18519746 DOI: 10.1189/jlb.0308171] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
CSF-1 is the major regulator of tissue macrophage development and function. A GM-CSF-dependent, CSF-1 receptor (CSF-1R)-deficient F4/80(hi)Mac-1(+)Gr1(-)CD11c(+) bone marrow macrophage (BMM) line (MacCsf1r-/-) was developed to study the roles of the eight intracellular CSF-1R tyrosines phosphorylated upon receptor activation. Retroviral expression of the wild-type CSF-1R rescued the CSF-1-induced survival, proliferation, differentiation, and morphological characteristics of primary BMM. Mutation of all eight tyrosines failed to rescue, whereas the individual Y --> F mutants (544, 559, 697, 706, 721, 807, 921, 974) rescued these CSF-1-inducible phenotypes to varying degrees. The juxtamembrane domain Y559F and activation loop Y807F mutations severely compromised proliferation and differentiation, whereas Y706, Y721F, and Y974F mutations altered morphological responses, and Y706F increased differentiation. Despite their retention of significant in vitro tyrosine kinase activity, Y559F and Y807F mutants exhibited severely impaired in vivo receptor tyrosine phosphorylation, consistent with the existence of cellular mechanisms inhibiting CSF-1R tyrosine phosphorylation that are relieved by phosphorylation of these two sites. The MacCsf1r-/- macrophage line will facilitate genetic and proteomic approaches to CSF-1R structure/function studies in the major disease-related CSF-1R-expressing cell type.
Collapse
Affiliation(s)
- Wenfeng Yu
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Ave., Bronx, NY 10461, USA
| | | | | | | | | | | | | |
Collapse
|
18
|
Krtil J, Pláteník J, Kazderová M, Tesar V, Zima T. Culture methods of glomerular podocytes. Kidney Blood Press Res 2007; 30:162-74. [PMID: 17502717 DOI: 10.1159/000102520] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Indexed: 12/29/2022] Open
Abstract
Podocytes (glomerular visceral epithelial cells) cover the exterior surface of the glomerular capillaries and contribute to the glomerular filtration membrane. Failure of podocyte function is involved in the progression of chronic glomerular disease; accordingly, research interest into podocyte biology is driven by the need for better protection and perhaps recovery of these cells in renal diseases. This review aims at summarizing available techniques for podocyte cell cultures from both the past and present, with special attention to the currently used methods. The establishment of classical primary cultures is based on isolation of glomeruli by differential sieving. Plating of glomeruli onto a collagen surface is followed by an outgrowth of cobblestone-like cells that, after replating, differentiate into arborized, mature podocytes. Currently, the majority of research studies use immortalized podocytic cell lines most often derived from transgenic mice bearing a conditional immortalizing gene. The podocytes can also be collected and cultured from healthy or diseased animal or patient urine. The urinary podocytes obtained from subjects with active glomerulopathies display higher proliferation potential and viability in vitro, perhaps due to disease-induced transdifferentiation. Finally, a list of phenotypic markers useful for identification and characterization of the cultured podocytic elements is provided.
Collapse
Affiliation(s)
- J Krtil
- Institute of Medical Biochemistry, First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
| | | | | | | | | |
Collapse
|
19
|
Kitagawa M, Tahara H, Kitagawa S, Oka H, Kudo Y, Sato S, Ogawa I, Miyaichi M, Takata T. Characterization of established cementoblast-like cell lines from human cementum-lining cells in vitro and in vivo. Bone 2006; 39:1035-1042. [PMID: 16857433 DOI: 10.1016/j.bone.2006.05.022] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2005] [Revised: 05/04/2006] [Accepted: 05/16/2006] [Indexed: 11/24/2022]
Abstract
To study cellular characteristics of human cementoblasts using a cellular model is important for understanding the mechanisms of homeostasis and regeneration of periodontal tissues. However, at present no immortalized human cementoblast cell line has been established due to limitation of the life span. In the present study, therefore, we attempted to establish human cementoblast-like cell lines by transfection with telomerase catalytic subunit hTERT gene. Two stable clones (HCEM-1 and -2) with high telomerase activity were obtained and they grew over 200 population doublings without significant growth retardation. The expression of mRNA for differentiation markers, type I collagen, alkaline phosphatase (ALP), runt-related transcription factor 2, osteocalcin, bone sialoprotein and cementum-derived protein was revealed in these clones by RT-PCR. Moreover, these cells showed high ALP activity and calcified nodule formation in vitro. Interestingly, HCEM-2 showed cementum like formation on the surface of hydroxyapatites granules by subcutaneous transplantation into immunodeficient mice with hydroxyapatite granules. Thus, we established human cementoblast-like cell lines. We suggest that HCEM cell lines can be useful cell models for investigating the characteristics of human cementoblasts.
Collapse
Affiliation(s)
- Masae Kitagawa
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Hidetoshi Tahara
- Department of Cell and Molecular Biology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, 734-8553, Japan
| | - Shoji Kitagawa
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Hiroko Oka
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Yasusei Kudo
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Sunao Sato
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Ikuko Ogawa
- Center of Oral Clinical Examination, Hiroshima University Hospital, Hiroshima, 734-8553, Japan
| | - Mutsumi Miyaichi
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan
| | - Takashi Takata
- Department of Oral Maxillofacial Pathobiology, Hiroshima, 734-8553, Japan; Center of Oral Clinical Examination, Hiroshima University Hospital, Hiroshima, 734-8553, Japan.
| |
Collapse
|
20
|
Kawata S, Suzuki J, Maruoka M, Mizutamari M, Ishida-Kitagawa N, Yogo K, Jat PS, Shishido T. Retrovirus-mediated conditional immortalization and analysis of established cell lines of osteoclast precursor cells. Biochem Biophys Res Commun 2006; 350:97-104. [PMID: 17005159 DOI: 10.1016/j.bbrc.2006.09.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Accepted: 09/05/2006] [Indexed: 12/18/2022]
Abstract
Osteoclast precursor cells (OPCs) have previously been established from bone marrow cells of SV40 temperature-sensitive T antigen-expressing transgenic mice. Here, we use retrovirus-mediated gene transfer to conditionally immortalize OPCs by expressing temperature-sensitive large T antigen (tsLT) from wild type bone marrow cells. The immortalized OPCs proliferated at the permissive temperature of 33.5 degrees C, but stopped growing at the non-permissive temperature of 39 degrees C. In the presence of receptor activator of NFkappaB ligand (RANKL), the OPCs differentiated into tartrate-resistant acid phosphatase (TRAP)-positive cells and formed multinucleate osteoclasts at 33.5 degrees C. From these OPCs, we cloned two types of cell lines. Both differentiated into TRAP-positive cells, but one formed multinucleate osteoclasts while the other remained unfused in the presence of RANKL. These results indicate that the established cell lines are useful for analyzing mechanisms of differentiation, particularly multinucleate osteoclast formation. Retrovirus-mediated conditional immortalization should be a useful method to immortalize OPCs from primary bone marrow cells.
Collapse
Affiliation(s)
- Shigehisa Kawata
- Laboratory of Molecular Oncology, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0101, Japan
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Menon RP, Menon MR, Shi-Wen X, Renzoni E, Bou-Gharios G, Black CM, Abraham DJ. Hammerhead ribozyme-mediated silencing of the mutant fibrillin-1 of tight skin mouse: insight into the functional role of mutant fibrillin-1. Exp Cell Res 2006; 312:1463-74. [PMID: 16488411 DOI: 10.1016/j.yexcr.2006.01.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Revised: 01/07/2006] [Accepted: 01/10/2006] [Indexed: 11/28/2022]
Abstract
The tight skin (Tsk/+) mouse is a model for fibrotic disorders. The genetic defect in the Tsk/+ is an in-frame duplication between exons 17 and 40 of the fibrillin-1 gene which gives rise to a large transcript and protein. Mice homozygous for the mutation die in utero, whereas heterozygotes survive and spontaneously develop connective tissue disease. In this study, we generated hammerhead ribozymes directed against the mutant fibrillin-1 transcript. A partially mispairing ribozyme was the most effective vehicle to cleave the mutant transcript without undesired cleavage of wild type transcripts, as shown by cell-free RNA cleavage and cleavage in cell lines harboring the ribozyme, by RT-PCR, Northern and Western Blotting. Global gene expression profiling using oligonucleotide microarrays showed the expected reduction in fibrillin-1 mRNA, and down-regulation of several gene cohorts in ribozyme harboring TskR1 cells compared to Tsk/+ cells. Two of the functional clusters included genes regulating extracellular matrix such as connective tissue growth factor, serpine-1 (plasminogen activator inhibitor-1) and TIMP-1 and TIMP-3, and those involved in cytoskeletal organization and myofibroblast formation including calponins and transgelin. Ribozyme-mediated inhibition was confirmed by Western Blot and functional analysis using cell-reporter systems and remodeling of three dimensional collagen gels. Our results underline the therapeutic potential of hammerhead ribozymes in dominant negative defects and suggest that changes in microfibril architecture brought about by fibrillin-1 mutation lead to a complex disease phenotype.
Collapse
Affiliation(s)
- Rajesh P Menon
- Centre for Rheumatology, Royal Free and University College Medical School, Division of Medicine, University College London (Hampstead Campus), Rowland Hill Street, London NW3 2PF2, UK.
| | | | | | | | | | | | | |
Collapse
|
22
|
Nandi S, Akhter MP, Seifert MF, Dai XM, Stanley ER. Developmental and functional significance of the CSF-1 proteoglycan chondroitin sulfate chain. Blood 2005; 107:786-95. [PMID: 16210339 PMCID: PMC1895624 DOI: 10.1182/blood-2005-05-1822] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The primary macrophage growth factor, colony-stimulating factor-1 (CSF-1), is homodimeric and exists in 3 biologically active isoforms: a membrane-spanning, cell-surface glycoprotein (csCSF-1) and secreted glycoprotein (sgCSF-1) and proteoglycan (spCSF-1) isoforms. To investigate the in vivo role of the chondroitin sulfate glycosaminoglycan (GAG) chain of spCSF-1, we created mice that exclusively express, in a normal tissue-specific and developmental manner, either the secreted precursor of spCSF-1 or the corresponding precursor in which the GAG addition site was mutated. The reproductive, hematopoietic tooth eruption and tissue macrophage defects of CSF-1-deficient, osteopetrotic Csf1(op)/Csf1(op) mice were corrected by transgenic expression of the precursors of either sgCSF-1 or spCSF-1. Furthermore, in contrast to the transgene encoding csCSF-1, both failed to completely correct growth retardation, suggesting a role for csCSF-1 in the regulation of body weight. However, spCSF-1, in contrast to sgCSF-1, completely resolved the osteopetrotic phenotype. Furthermore, in transgenic lines expressing different concentrations of sgCSF-1 or spCSF-1, spCSF-1 more efficiently corrected Csf1(op)/Csf1(op) defects of tooth eruption, eyelid opening, macrophage morphology, and B-cell deficiency than sgCSF-1. These results indicate an important role of the CSF-1 chondroitin sulfate proteoglycan in in vivo signaling by secreted CSF-1.
Collapse
Affiliation(s)
- Sayan Nandi
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA
| | | | | | | | | |
Collapse
|
23
|
Kitagawa M, Kitagawa S, Kudo Y, Ogawa I, Miyauchi M, Tahara H, Ide T, Takata T. Establishment of cementoblast cell lines from rat cementum lining cells by transfection with temperature-sensitive simian virus-40 T-antigen gene. Bone 2005; 37:220-6. [PMID: 15987673 DOI: 10.1016/j.bone.2005.04.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2005] [Revised: 03/23/2005] [Accepted: 04/05/2005] [Indexed: 11/23/2022]
Abstract
Defining the regulatory mechanisms promoting differentiation and proliferation of cementoblasts has not been well understood, because of the lack of cell models in vitro. To establish an in vitro cell model for the cementoblasts, extracted rat molars obtained from 8-week-old rats were used. Cells lining the root surface (cemetoblasts) were obtained by an enzymatic digestion method, and immediately immortalized by transfection of thermolabile SV40 T-antigen gene. The transfected cementum lining cell clones, RCM-C3 and -C4, were maintained for more than 200 population doublings (PD), while the original cells stopped their growth at 60 PD. Thus, immortalized cell lines decreased expression of SV40 T-antigen and subsequently cell proliferation at non-permissive temperature (39 degrees C). Reverse-transcribed-polymerase chain reaction indicated expression of gene for type I collagen, alkaline phosphatase (ALP), osteopontin, and osteocalcin mRNA at both permissive (33 degrees C) and non-permissive (39 degrees C) temperatures. RCM-C4 expressed higher bone siaploprotein (BSP) mRNA than RCM-C3, and further RCM-C4 showed higher BSP mRNA at 39 degrees C than 33 degrees C. High ALP activity and mineralized nodule formation were observed at 39 degrees C in both cell lines. These findings suggested that the cell lines, RCM-C3 and -C4, are useful model for studying the regulatory mechanisms of differentiation and proliferation of cementoblasts.
Collapse
Affiliation(s)
- Masae Kitagawa
- Department of Oral Maxillofacial Pathobiology, Division of Frontier Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | | | | | | | | | | | | | | |
Collapse
|
24
|
May T, Mueller PP, Weich H, Froese N, Deutsch U, Wirth D, Kröger A, Hauser H. Establishment of murine cell lines by constitutive and conditional immortalization. J Biotechnol 2005; 120:99-110. [PMID: 16026879 DOI: 10.1016/j.jbiotec.2005.03.027] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 03/01/2005] [Accepted: 03/16/2005] [Indexed: 10/25/2022]
Abstract
Mouse cell lines were immortalized by introduction of specific immortalizing genes. Embryonic and adult animals and an embryonal stem cell line were used as a source of primary cells. The immortalizing genes were either introduced by DNA transfection or by ecotropic retrovirus transduction. Fibroblasts were obtained by expression of SV40 virus large T antigen (TAg). The properties of the resulting fibroblast cell lines were reproducible, independent of the donor mouse strains employed and the cells showed no transformed properties in vitro and did not form tumors in vivo. Endothelial cell lines were generated by Polyoma virus middle T antigen expression in primary embryonal cells. These cell lines consistently expressed relevant endothelial cell surface markers. Since the expression of the immortalizing genes was expected to strongly influence the cellular characteristics fibroblastoid cells were reversibly immortalized by using a vector that allows conditional expression of the TAg. Under inducing conditions, these cells exhibited properties that were highly similar to the properties of constitutively immortalized cells. In the absence of TAg expression, cell proliferation stops. Cell growth is resumed when TAg expression is restored. Gene expression profiling indicates that TAg influences the expression levels of more than 1000 genes that are involved in diverse cellular processes. The data show that conditionally immortalized cell lines have several advantageous properties over constitutively immortalized cells.
Collapse
Affiliation(s)
- Tobias May
- Department of Gene Regulation and Differentiation, German Research Center for Biotechnology, GBF, Mascheroder Weg 1, D-38124 Braunschweig, Germany
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Li Z, Wang X, Yu RYL, Ding BB, Yu JJ, Dai XM, Naganuma A, Stanley ER, Ye BH. BCL-6 negatively regulates expression of the NF-kappaB1 p105/p50 subunit. THE JOURNAL OF IMMUNOLOGY 2005; 174:205-14. [PMID: 15611242 DOI: 10.4049/jimmunol.174.1.205] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BCL-6 is a transcription repressor frequently deregulated in non-Hodgkin's B cell lymphomas. Its activity is also critical to germinal center development and balanced Th1/Th2 differentiation. Previous studies have suggested that NF-kappaB activity is suppressed in germinal center and lymphoma B cells that express high levels of BCL-6, and yet the reason for this is unknown. We report in this study that BCL-6 can bind to three sequence motifs in the 5' regulatory region of NF-kappaB1 in vitro and in vivo, and repress NF-kappaB1 transcription both in reporter assays and in lymphoma B cell lines. BCL-6(-/-) mice further confirm the biological relevance of BCL-6-dependent regulation of NF-kappaB1 because BCL-6 inactivation caused notable increase in p105/p50 proteins in several cell types. Among these, BCL-6(-/-) macrophage cell lines displayed a hyperproliferation phenotype that can be reversed by NF-kappaB inhibitors, e.g., N-tosyl-l-phenylalanine chloromethyl ketone and SN50, a result that is consistent with increased nuclear kappaB-binding activity of p50 homodimer and p50/p65 heterodimer. Our results demonstrate that BCL-6 can negatively regulate NF-kappaB1 expression, thereby inhibiting NF-kappaB-mediated cellular functions.
Collapse
Affiliation(s)
- Zhiping Li
- Department of Cell Biology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Eaton MJ, Duplan H. Useful cell lines derived from the adrenal medulla. Mol Cell Endocrinol 2004; 228:39-52. [PMID: 15541571 DOI: 10.1016/j.mce.2003.02.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2002] [Accepted: 02/06/2003] [Indexed: 01/07/2023]
Abstract
Five approaches for the preparation of adrenal chromaffin cell lines have been developed. Initially, continuous chromaffin lines were derived from spontaneous pheochromocytoma tumors of the medulla, either from murine or human sources, such as the rat PC12 cell line and the human KNA and KAT45 cell lines. Over the last few decades, more sophisticated molecular methods have allowed for induced tumorigenesis and targeted oncogenesis in vivo, where isolation of specific populations of mouse cell lines of endocrine origin have resulted in model cells to examine a variety of regulatory pathways in the chromaffin phenotype. As well, conditional immortalization with retroviral infection of chromaffin precursors has provided homogeneous and expandable chromaffin cells for transplant studies in animal models of pain. This same strategy of immortalization with conditionally expressed oncogenes has been expanded recently to create the first disimmortalizable chromaffin cells, with an excisable oncogenic cassette, as might be envisioned for the creation of human chromaffin cell lines. Eventually, as we increase our understanding of regulating the phenotypic fate of chromaffin cells in vitro, stem or progenitor adrenal medullary cell lines will be derived as an alternative source for expansion and clinical use.
Collapse
Affiliation(s)
- M J Eaton
- The Miami Project To Cure Paralysis, University of Miami School of Medicine, 1095 N.W. 14th Terrace (R-48), Miami, FL 33136, USA.
| | | |
Collapse
|
27
|
Kartsogiannis V, Ng KW. Cell lines and primary cell cultures in the study of bone cell biology. Mol Cell Endocrinol 2004; 228:79-102. [PMID: 15541574 DOI: 10.1016/j.mce.2003.06.002] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2003] [Accepted: 06/12/2003] [Indexed: 12/13/2022]
Abstract
Bone is a metabolically active and highly organized tissue consisting of a mineral phase of hydroxyapatite and amorphous calcium phosphate crystals deposited in an organic matrix. Bone has two main functions. It forms a rigid skeleton and has a central role in calcium and phosphate homeostasis. The major cell types of bone are osteoblasts, osteoclasts and chondrocytes. In the laboratory, primary cultures or cell lines established from each of these different cell types provide valuable information about the processes of skeletal development, bone formation and bone resorption, leading ultimately, to the formulation of new forms of treatment for common bone diseases such as osteoporosis.
Collapse
|
28
|
May T, Hauser H, Wirth D. Transcriptional control of SV40 T-antigen expression allows a complete reversion of immortalization. Nucleic Acids Res 2004; 32:5529-38. [PMID: 15486202 PMCID: PMC524297 DOI: 10.1093/nar/gkh887] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Conditional proliferation of mouse embryo fibroblasts was achieved with a novel autoregulatory vector for Tet-dependent expression of the SV40 T-antigen. The majority of cell clones that were isolated under induced conditions showed strict regulation of cell growth. Status switches were found to be fully reversible and highly reproducible with respect to gene expression characteristics. A consequence of T-antigen expression is a significant deregulation of >400 genes. Deinduced cells turn to rest in G0/G1 phase and exhibit a senescent phenotype. The cells are not oncogenic and no evidence for transformation was found after several months of cultivation. Conditional immortalization allows diverse studies including those on cellular activities without the influence of the immortalizing gene(s), senescence as well as secondary effects from T-antigen expression.
Collapse
Affiliation(s)
- Tobias May
- Department of Gene Regulation and Differentiation, GBF-German Research Center for Biotechnology, Mascheroder Weg 1, D-38124 Braunschweig, Germany
| | | | | |
Collapse
|
29
|
Suzuki J, Sukezane T, Akagi T, Georgescu MM, Ohtani M, Inoue H, Jat PS, Goff SP, Hanafusa H, Shishido T. Loss of c-abl facilitates anchorage-independent growth of p53- and RB- deficient primary mouse embryonic fibroblasts. Oncogene 2004; 23:8527-34. [PMID: 15378021 DOI: 10.1038/sj.onc.1207894] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The c-abl tyrosine kinase is the proto-oncogene of the v-abl oncogene of the Abelson murine leukemia virus. Although mutational variants of c-Abl can exhibit gain of function and can produce a transformed phenotype, the function of c-Abl in transformation remained unclear. Here, we report that the loss of c-abl facilitates transformation. c-abl-knockout mouse embryonic fibroblasts (MEFs) immortalized by SV40 T antigen acquired anchorage-independent growth, and by constructing mutational variants of T antigen we showed that binding of large T antigen to p53 and RB was necessary to induce anchorage-independent growth. Although c-abl/p53 double-knockout MEFs did not undergo anchorage-independent growth, those expressing human papilloma virus 16 E7, which mainly inactivates RB, did. Our results show that the loss of c-abl facilitates anchorage-independent growth in the context of p53 and RB deficiency, and suggest that loss of function of c-abl facilitates some types of transformation.
Collapse
Affiliation(s)
- Jun Suzuki
- Laboratory of Molecular Oncology, Osaka Bioscience Institute, 6-2-4 Furuedai, Suita, Osaka 565-0874, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Cotsiki M, Lock RL, Cheng Y, Williams GL, Zhao J, Perera D, Freire R, Entwistle A, Golemis EA, Roberts TM, Jat PS, Gjoerup OV. Simian virus 40 large T antigen targets the spindle assembly checkpoint protein Bub1. Proc Natl Acad Sci U S A 2004; 101:947-52. [PMID: 14732683 PMCID: PMC327122 DOI: 10.1073/pnas.0308006100] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mitotic spindle checkpoint protein Bub1 has been found to be mutated at low frequency in certain human cancers characterized by aneuploidy. Simian virus 40 large T antigen efficiently immortalizes rodent cells and occasionally transforms them to tumorigenicity. T antigen can also cause genomic instability, inducing chromosomal aberrations and aneuploidy. Here, we report an interaction between Bub1 and T antigen. T antigen coimmunoprecipitates with endogenous Bub1 and Bub3, another component of the spindle checkpoint complex. Genetic analysis demonstrates that the interaction of T antigen with Bub1 is not required for immortalization but is closely correlated with transformation. T antigen induces an override of the spindle checkpoint dependent on Bub1 binding. This interaction with proteins of the spindle checkpoint machinery suggests another role for T antigen and provides insight into its ability to cause chromosomal aberrations, aneuploidy, and transformation.
Collapse
Affiliation(s)
- Marina Cotsiki
- Ludwig Institute for Cancer Research, Royal Free and University College School of Medicine, Courtauld Building, 91 Riding House Street, London W1W 7BS, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Orosz DE, Woost PG, Kolb RJ, Finesilver MB, Jin W, Frisa PS, Choo CK, Yau CF, Chan KW, Resnick MI, Douglas JG, Edwards JC, Jacobberger JW, Hopfer U. GROWTH, IMMORTALIZATION, AND DIFFERENTIATION POTENTIAL OF NORMAL ADULT HUMAN PROXIMAL TUBULE CELLS. ACTA ACUST UNITED AC 2004; 40:22-34. [PMID: 14748622 DOI: 10.1290/1543-706x(2004)40<22:giadpo>2.0.co;2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human proximal tubule epithelial cell lines are potentially useful models to elucidate the complex cellular and molecular details of water and electrolyte homeostasis in the kidney. Samples of normal adult human kidney tissue were obtained from surgical specimens, and S1 segments of proximal convoluted tubules were microdissected, placed on collagen-coated culture plate inserts, and cocultured with lethally irradiated 3T3 fibroblasts. Primary cultures of proximal tubule epithelial cells were infected with a replication-defective retroviral construct encoding either wild-type or temperature-sensitive simian virus 40 large T-antigen. Cells forming electrically resistive monolayers were selected and expanded in culture. Three cell lines (HPCT-03-ts, HPCT-05-wt, and HPCT-06-wt) were characterized for proximal tubule phenotype by electron microscopy, electrophysiology, immunofluorescence, Southern hybridization, and reverse transcriptase-polymerase chain reaction. Each of the three formed polarized, resistive epithelial monolayers with apical microvilli, tight junctional complexes, numerous mitochondria, well-developed Golgi complexes, extensive endoplasmic reticulum, convolutions of the basolateral plasma membrane, and a primary cilium. Each exhibited succinate, phosphate, and Na,K- adenosine triphosphatase (ATPase) transport activity, as well as acidic dipeptide- and adenosine triphosphate-regulated mechanisms of ion transport. Transcripts for Na(+)-bicarbonate cotransporter, Na(+)-H(+) exchanger isoform 3, Na,K-ATPase, parathyroid hormone receptor, epidermal growth factor receptor, and vasopressin V2 receptor were identified. Furthermore, immunoreactive sodium phosphate cotransporter type II, vasopressin receptor V1a, and CLIC-1 (NCC27) were also identified. These well-differentiated, transport-competent cell lines demonstrated the growth, immortalization, and differentiation potential of normal, adult, human proximal tubule cells and consequently have wide applicability in cell biology and renal physiology.
Collapse
Affiliation(s)
- David E Orosz
- Department of Physiology, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Olson JK, Zamvil SS, Miller SD. Efficient technique for immortalization of murine microglial cells relevant for studies in murine models of multiple sclerosis. J Neurosci Methods 2003; 128:33-43. [PMID: 12948546 DOI: 10.1016/s0165-0270(03)00145-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Microglia are macrophage-like cells that populate the central nervous system (CNS) and become activated upon injury or infection. Microglia have been implicated as playing critical roles in various CNS diseases including multiple sclerosis (MS), a human autoimmune demyelinating disease, as well as in other neurodegenerative diseases. Two well-characterized models of MS, relapsing experimental autoimmune encephalomyelitis (R-EAE) and Theiler's murine encephalomyelitis virus (TMEV)-induced demyelinating disease, are inducible in SJL mice and model the relapsing-remitting and chronic-progressive forms of MS, respectively. These models are useful for the study of the mechanisms of initiation, progression, and therapy of the disease. Currently, a major limitation to studying the functions of microglia in these murine models of MS is the restricted number of cells capable of being isolated from the CNS of neonatal mice and propagated in culture. The current studies describe the preparation of SV-40 large T antigen-immortalized mouse microglia lines, M4T.4 and M4T.6, from the SJL/J mice. The immortalization technique was very efficient requiring only 6 weeks to develop long-term, highly replicating cell lines. The resulting microglia cell lines remain quiescent, but are induced to express various immune cytokines and to function as efficient antigen presenting cells upon activation with IFN-gamma or infection with TMEV. Thus, the SV-40 large T antigen immortalized microglia lines react to innate and infectious stimuli similar to primary microglia isolated from neonatal mice, but are more easily maintained in culture. This technique should allow for the efficient cultivation of large numbers of microglial cells from a variety of disease-relevant mouse strains, including knock-out and transgenic mice.
Collapse
Affiliation(s)
- Julie K Olson
- Department of Microbiology-Immunology and Interdepartmental Immunobiology Program, Northwestern University Medical School, 303 East Chicago Avenue, Chicago, IL 60611, USA
| | | | | |
Collapse
|
33
|
Lieberherr M, Cournot G, Robins SP. Guidelines for using in vitro methods to study the effects of phyto-oestrogens on bone. Br J Nutr 2003; 89 Suppl 1:S59-73. [PMID: 12725651 DOI: 10.1079/bjn2002797] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
These guidelines review the relevant literature on the way plant phyto-oestrogens act on bone and the responsiveness of different bone cell systems to phyto-oestrogenic compounds. The primary emphasis is on the experimental conditions used, the markers available for assessing osteoblast and osteoclast function, and their expected sensitivity. Finally, we assess the published results to derive some general recommendations for in vitro experiments in this area of research.
Collapse
Affiliation(s)
- Michèle Lieberherr
- Laboratoire de Nutrition et de Sécurité Alimentaire, Institut National de la Recherche Agronomique, F-78350 Jouy-en-Josas, France.
| | | | | |
Collapse
|
34
|
Oostendorp RAJ, Medvinsky AJ, Kusadasi N, Nakayama N, Harvey K, Orelio C, Ottersbach K, Covey T, Ploemacher RE, Saris C, Dzierzak E. Embryonal subregion-derived stromal cell lines from novel temperature-sensitive SV40 T antigen transgenic mice support hematopoiesis. J Cell Sci 2002; 115:2099-108. [PMID: 11973351 DOI: 10.1242/jcs.115.10.2099] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Throughout life, the hematopoietic system requires a supportive microenvironment that allows for the maintenance and differentiation of hematopoietic stem cells (HSC). To understand the cellular interactions and molecules that provide these functions, investigators have previously established stromal cell lines from the late gestational stage and adult murine hematopoietic microenvironments. However, the stromal cell microenvironment that supports the emergence, expansion and maintenance of HSCs during mid-gestational stages has been largely unexplored. Since several tissues within the mouse embryo are known to harbor HSCs (i.e. aortagonads-mesonephros, yolk sac, liver), we generated numerous stromal cell clones from these mid-gestational sites. Owing to the limited cell numbers,isolations were performed with tissues from transgenic embryos containing the ts SV40 Tag gene (tsA58) under the transcriptional control of constitutive and ubiquitously expressing promoters. We report here that the growth and cloning efficiency of embryonic cells (with the exception of the aorta) is increased in the presence of the tsA58 transgene. Furthermore, our results show that the large panel of stromal clones isolated from the different embryonal subregions exhibit heterogeneity in their ability to promote murine and human hematopoietic differentiation. Despite our findings of heterogeneity in hematopoietic growth factor gene expression profiles, high-level expression of some factors may influence hematopoietic differentiation. Interestingly, a few of these stromal clones express a recently described chordin-like protein, which is an inhibitor of bone morphogenic proteins and is preferentially expressed in cells of the mesenchymal lineage.
Collapse
|
35
|
Larsson J, Goumans MJ, Sjöstrand LJ, van Rooijen MA, Ward D, Levéen P, Xu X, ten Dijke P, Mummery CL, Karlsson S. Abnormal angiogenesis but intact hematopoietic potential in TGF-beta type I receptor-deficient mice. EMBO J 2001; 20:1663-73. [PMID: 11285230 PMCID: PMC145465 DOI: 10.1093/emboj/20.7.1663] [Citation(s) in RCA: 421] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Deletion of the transforming growth factor beta1 (TGF-beta1) gene in mice has previously suggested that it regulates both hematopoiesis and angiogenesis. To define the function of TGF-beta more precisely, we inactivated the TGF-beta type I receptor (TbetaRI) gene by gene targeting. Mice lacking TbetaRI die at midgestation, exhibiting severe defects in vascular development of the yolk sac and placenta, and an absence of circulating red blood cells. However, despite obvious anemia in the TbetaRI(-/-) yolk sacs, clonogenic assays on yolk sac-derived hematopoietic precursors in vitro revealed that TbetaRI(-/-) mice exhibit normal hematopoietic potential compared with wild-type and heterozygous siblings. Endothelial cells derived from TbetaRI-deficient embryos show enhanced cell proliferation, improper migratory behavior and impaired fibronectin production in vitro, defects that are associated with the vascular defects seen in vivo. We thus demonstrate here that, while TbetaRI is crucial for the function of TGF-beta during vascular development and can not be compensated for by the activin receptor-like kinase-1 (ALK-1), functional hematopoiesis and development of hematopoietic progenitors is not dependent on TGF-beta signaling via TbetaRI.
Collapse
Affiliation(s)
| | - Marie-José Goumans
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| | | | - Marga A. van Rooijen
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| | - Dorien Ward
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| | | | | | - Peter ten Dijke
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| | - Christine L. Mummery
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| | - Stefan Karlsson
- Molecular Medicine and Gene Therapy, Institute of Laboratory Medicine and Department of Medicine, Lund University Hospital, Lund, Sweden,
Netherlands Cancer Institute, Amsterdam and Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht, The Netherlands Corresponding author e-mail:
| |
Collapse
|
36
|
Li H, Söderbärg K, Houshmand H, You ZY, Magnusson G. Effect on polyomavirus T-antigen function of mutations in a conserved leucine-rich segment of the DnaJ domain. J Virol 2001; 75:2253-61. [PMID: 11160729 PMCID: PMC114809 DOI: 10.1128/jvi.75.5.2253-2261.2001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The N-terminal part of the mouse polyomavirus T antigens contains a highly conserved segment (-LLELLKL-), including amino acid residues 13 to 19. The sequence motif is predicted to form alpha helix I in the DnaJ domain of the T antigens. Four mutants with conservative substitutions of amino acid residues 13 and 14 were constructed. Of the four substitutions, L13M, L13I, L13V, and L14V, only L13V resulted in a phenotypic change. In transfected mouse cells, L13V large T antigen showed a more than 100-fold-reduced viral DNA synthesis. The viral replication could not be rescued by cotransfection of the cells with DNA expressing small t antigen or a large T antigen truncated at the C terminus that would compensate for a defect in host cell stimulation. In contrast to the effect on DNA replication, the L13V substitution in large T antigen did not prevent complex formation with Hsc70 and the Rb protein. Also, the activity of the protein in transactivation of transcription from the adenovirus E2 promoter was unimpaired, showing that the transcription factor E2F was released from pRb. The L13V substitution also caused a defect in small t antigen. However, this phenotypic change was due to protein instability. In contrast, middle T antigen with the L13V substitution remained stable and functional in cellular transformation. Together, the data show that the effect of the L13V substitution did not abrogate the Hsc70 interaction of the DnaJ domain. However, it is possible that the substitution of amino acid residue 13 affected specific DnaJ functions of large T antigen.
Collapse
Affiliation(s)
- H Li
- Department of Medical Biochemistry and Microbiology, Biomedical Center, Uppsala University, Uppsala, Sweden
| | | | | | | | | |
Collapse
|
37
|
Eaton MJ, Frydel BR, Lopez TL, Nie XT, Huang J, McKillop J, Sagen J. Generation and initial characterization of conditionally immortalized chromaffin cells. J Cell Biochem 2000. [DOI: 10.1002/1097-4644(2000)79:1<38::aid-jcb50>3.0.co;2-u] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
38
|
Powell AJ, Darmon AJ, Gonos ES, Lam EW, Peden KW, Jat PS. Different functions are required for initiation and maintenance of immortalization of rat embryo fibroblasts by SV40 large T antigen. Oncogene 1999; 18:7343-50. [PMID: 10602490 DOI: 10.1038/sj.onc.1203154] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We have used two different, but complementary assays to characterize functions of SV40 T antigen that are necessary for its ability to immortalize rat embryo fibroblasts. In accordance with previous work, we found that several functions were required. These include activities that map to the p53 binding domain and the amino terminal 176 amino acids which contain the J domain as well as the CR1 and CR2 domain required for binding and sequestering the RB family of pocket proteins. Moreover, we found that even though activities dependent only upon the amino terminus were sufficient for immortalization they were unable to maintain it. This suggests that immortalization by these amino terminal functions requires either additional events or immortalization of a subset of cells within the heterogeneous rat embryo fibroblast population. We further found that an activity dependent upon amino acids 17 - 27 which remove a portion of the CR1 domain and the predicted alpha-1 helix of the J domain was not necessary to maintain growth but was required for direct immortalization suggesting that at least one of the functions required initially was not required to maintain the immortal state. This represents the first demonstration that some of the functions required for maintenance of the immortal state differ from those required for initiation of immortalization.
Collapse
Affiliation(s)
- A J Powell
- Ludwig Institute for Cancer Research, Royal Free and University College School of Medicine, Courtauld Building, 91 Riding House Street, London W1P 8BT, UK
| | | | | | | | | | | |
Collapse
|
39
|
Braiterman LT, Watkins PA, Moser AB, Smith KD. Peroxisomal very long chain fatty acid beta-oxidation activity is determined by the level of adrenodeukodystrophy protein (ALDP) expression. Mol Genet Metab 1999; 66:91-9. [PMID: 10068511 DOI: 10.1006/mgme.1998.2789] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Impaired peroxisomal beta-oxidation of saturated very long chain fatty acids (VLCFA, >/=C22:0) results in increased VLCFA levels in the tissues and body fluids of patients with disorders of peroxisomal biogenesis (i.e., Zellweger syndrome and neonatal adrenoleukodystrophy) and single peroxisomal protein defects (i.e., X-linked adrenoleukodystrophy (X-ALD) and acyl-CoA oxidase deficiency). We show that SV40T transformation also results in impaired peroxisomal beta-oxidation and VLCFA accumulation despite the presence of abundant peroxisomes. To explore the mechanism responsible for this observation, we have examined expression of key components of peroxisomal VLCFA beta-oxidation. We found that expression of both acyl-CoA oxidase, the rate limiting enzyme of peroxisomal VLCFA beta-oxidation and the adrenoleukodystrophy protein (ALDP), the defective gene product in X-ALD, are reduced after SV40T transformation. Surprisingly, ALDP overexpression by itself restores peroxisomal VLCFA beta-oxidation in SV40T-transformed control and X-ALD cells. These results demonstrate that ALDP is a fundamental component in VLCFA peroxisomal beta-oxidation and may serve as a "gatekeeper" for VLCFA homeostasis.
Collapse
Affiliation(s)
- L T Braiterman
- Kennedy Krieger Research Institute, 707 N. Broadway, Baltimore, Maryland, 21205, USA
| | | | | | | |
Collapse
|
40
|
Abstract
Cultured cell lines that maintain specific differentiated phenotypes have been indispensable tools in cell biology. Progress in understanding the function of differentiated cells in vivo can be facilitated by creating cell lines via immortalizing gene transduction, if they retain the essential differentiated features of the same cells in vivo. Rodent cells immortalize spontaneously with a frequency of 10(-5) to 10(-6). Thus, it is easy to isolate immortal cells from rodent cell populations even without the transfer of immortalizing genes. Immortalizing genes can be used to increase this frequency to approximately 100%. In contrast, the spontaneous immortalization of human cells is a very rare event; the frequency is thought to be < 10(-12). Immortalizing genes can also be used to increase this frequency. Several genes that promise efficient immortalization of cultured cells have been identified. Immortalizing genes include simian virus 40 large T antigen, papillomaviruses E6 and E7, adenovirus E1A, Epstein-Barr virus, human T-cell leukemia virus, herpesvirus saimiri, oncogenes, and mutant p53 gene. Equally important, innovative means of gene delivery have been developed as well. These immortalizing genes, together with gene transfer methodologies, have provided the means to generate cell lines from cell types that are not abundant or are difficult to obtain in pure form in primary culture, are in short supply as human cells, and/or have brief lifetimes in culture. This chapter focuses primarily on the immortalization method by gene transfection. The chapter is not meant to be comprehensive, but rather to provide an account of the power and usefulness of immortalization methodology.
Collapse
Affiliation(s)
- Y Katakura
- Laboratory of Cellular Regulation Technology, Graduate School of Genetic Resources Technology, Kyushu University, Fukuoka, Japan
| | | | | |
Collapse
|
41
|
Abstract
Progress in the field of osteoclast gene regulation has been hampered significantly by the lack of such cell lines. In this study, mouse osteoclast precursor cells were elicited in an osteoclast-inductive coculture system and immortalized using SV40 large T antigen. One of the osteoclast precursor cell lines (MOCP-5) forms 95% tartrate-resistant acid phosphatase positive (TRAP+) multinuclear osteoclast-like cells (OCLs) in the coculture system. The yield of TRAP+ OCLs was 4.5-7x10(4) cells per 10 cm2 dish. Expression of SV40 large T antigen was visualized in the nucleus of MOCP-5 cells and OCLs by immunohistochemistry. MOCP-5 cells were positive for MoMa-2 antigen and nonspecific esterase but negative for F4/80 antigen. OCLs derived from MOCP-5 cells were positive for able to form extensive resorption bone pits on bone slices. The resorbing activity of the OCLs was comparable to that of authentic mouse osteoclasts. Pit formation was inhibited by salmon calcitonin (CT). Acid production by OCLs was demonstrated by vital staining with acridine orange. The OCLs expressed cathepsin K and CT receptors. MOCP-5 cells could be transfected by a construct that carries the beta-galactosidase gene. Transfected MOCP-5 cells expressing beta-galactosidase retain the ability to differentiate into OCLs, indicating a useful model for osteoclast gene regulation. To date, the MOCP-5 cell line has been maintained in continuous culture for 23 months and has maintained the capacity to differentiate into osteoclasts throughout this time. In summary, these data show that a stable immortalized osteoclast precursor cell line has been established and that the immortalization with SV40 large T oncogene does not prevent osteoclast precursor cell differentiation.
Collapse
Affiliation(s)
- W Chen
- Department of Cytokine Biology, Forsyth Dental Center, Boston, Massachusetts. USA
| | | |
Collapse
|
42
|
Hegde NR, Lewin HA, Duggan MJ, Stabel JR, Srikumaran S. Development of a syngeneic bovine fibroblast cell line: implications for the study of bovine cytotoxic T lymphocytes. Viral Immunol 1998; 11:37-48. [PMID: 9586696 DOI: 10.1089/vim.1998.11.37] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The study of T-cell-mediated cytotoxicity in domestic animals, especially in cattle, has been hampered by the lack of proper restimulatory as well as target systems. While the currently available bovine cell lines have not been typed for the major histocompatibility complex (MHC) class I molecules they express, methods to derive lines of cells obtained from animals that are MHC-typed have not been thoroughly explored. In the present study, we describe a method for the development of cell lines from MHC-typed animals. Cells obtained from the skin of a calf typed as bovine lymphocyte antigen-A11/-A13 were transfected with a plasmid containing the whole genome of simian vacuolating virus 40 (SV40). A cell line was derived from the resultant transfectants. This cell line expressed bovine MHC class I molecules on the cell surface, and SV40 large T antigen in the nucleus. The cells were permissive to the replicative cycle of bovine herpesvirus-1 (BHV-1), and the major glycoproteins of BHV-1 were expressed at expected times after infection. The present study should contribute to the study of cytotoxic T lymphocyte response of cattle to BHV-1 and other intracellular pathogens.
Collapse
Affiliation(s)
- N R Hegde
- Department of Veterinary and Biomedical Sciences, University of Nebraska-Lincoln, 68583-0905, USA
| | | | | | | | | |
Collapse
|
43
|
Abstract
The aim of this work was to culture conditionally immortalized cells that possess the potential to differentiate into mechanosensory hair cells. Utricular epithelia at embryonic stage E16 were cultured from the vestibular system of the H2kbtsA58 transgenic mouse (Immortomouse) that carries a conditionally expressed immortalizing gene derived from the simian virus 40. Immunolabelling showed that the immortalizing transgene product, the T antigen (Tag), was expressed in utricular cells under permissive conditions and that it was inactivated under non-permissive conditions. Several morphologically distinct cell types proliferated when Tag was expressed, including those that resembled fibroblasts, nerve cells and epithelial cells. Mixed cultures of cells from the utricle, passaged up to 50 times every 3-4 days over a period of 5 months, were subsequently allowed to differentiate for 10 days by transferring them to non-permissive conditions. Monoclonal antibody markers were used to locate expression of hair cell specific antigens. One antibody that normally labels stereociliary bundles from postnatal stage P4-6 labelled cellular projections from a population of spheroid cells that were distributed across the culture surface. A second antibody that normally labels stereociliary bundles did not label the same structures. We conclude that utricular hair cell progenitors can be derived from the H2kbtsA58 transgenic mouse but that under the experimental conditions used they do not follow the normal pattern of differentiation.
Collapse
Affiliation(s)
- M C Holley
- Department of Physiology, School of Medical Sciences, Bristol, U.K
| | | | | |
Collapse
|
44
|
Obata M, Lee GH, Kanda H, Kitagawa T, Ogawa K. Loss of heterozygosity at loci on chromosome 4, a common genetic event during the spontaneous immortalization of mouse embryonic fibroblasts. Mol Carcinog 1997. [DOI: 10.1002/(sici)1098-2744(199705)19:1<17::aid-mc3>3.0.co;2-k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
45
|
Ghosh-Choudhury N, Harris MA, Wozney J, Mundy GR, Harris SE. Clonal osteoblastic cell lines from p53 null mouse calvariae are immortalized and dependent on bone morphogenetic protein 2 for mature osteoblastic phenotype. Biochem Biophys Res Commun 1997; 231:196-202. [PMID: 9070248 DOI: 10.1006/bbrc.1996.5962] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
p53 protein regulates cell cycle progression and its absence will result in unlimited cell divisions required for immortalization of cells. Immortalized osteoblastic cell lines were established from p53 null mouse calvariae of normal phenotype. The clonal murine cell lines demonstrated osteoblastic phenotype as exemplified by alkaline phosphatase enzyme activity. They also express bone morphogenetic protein 2 (BMP2) mRNA. Addition of recombinant BMP2 to these cells dramatically increased the alkaline phosphatase activity in a dose dependent manner. In the absence of BMP2 these cells do not undergo osteoblastic differentiation. Treatment of these cells with recombinant bone morphogenetic protein 2 stimulated differentiated osteoblast formation, as determined by mineralized nodule formation. Thus, these immortalized cells in culture represent osteoblast progenitors that lack p53 protein and respond to osteogenic stimuli. These cell lines offer a model system to study the role of p53 in osteoblastic differentiation and programmed cell death. Also these cells will be useful in studying the effects of p53 on transcriptional regulation of osteoblast specific gene expression.
Collapse
Affiliation(s)
- N Ghosh-Choudhury
- Department of Medicine, University of Texas Health Science Center at San Antonio 78284, USA
| | | | | | | | | |
Collapse
|
46
|
Mazars GR, Jat PS. Expression of p24, a novel p21Waf1/Cip1/Sdi1-related protein, correlates with measurement of the finite proliferative potential of rodent embryo fibroblasts. Proc Natl Acad Sci U S A 1997; 94:151-6. [PMID: 8990177 PMCID: PMC19264 DOI: 10.1073/pnas.94.1.151] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Normal mammalian fibroblasts undergo a limited number of divisions when cultured in vitro before entering a state of replicative senescence. The molecular basis for the determination of the finite mitotic potential is not known. Nevertheless, simian virus 40 T antigen, among other oncogenes, is able to prevent senescence in rodent embryo fibroblasts. T antigen immortalized cells are dependent upon this protein for maintaining growth once their normal mitotic life span has elapsed. Even though the mechanism that measures the finite mitotic potential of rodent fibroblasts is not known, it has been shown that it continues to function normally in the presence of this immortalizing gene. Accumulation of cyclin-dependent kinase inhibitors such as p21Waf1/Cip1/Sdi1 could potentially be a component of the mechanism that determines the finite life span. Here we show that accumulation of p21Waf1/Cip1/Sdi1 does not correlate with this biological counting mechanism, but we have identified p24, a p21Waf1/Cip1/Sdi1-related protein, whose accumulation does correlate with the measurement of the finite proliferative potential of rodent embryo fibroblasts and suggest that sequestration might be a mechanism by which its activity is regulated.
Collapse
Affiliation(s)
- G R Mazars
- Ludwig Institute for Cancer Research, London, United Kingdom
| | | |
Collapse
|
47
|
Dorling A, Stocker C, Tsao T, Haskard DO, Lechler RI. In vitro accommodation of immortalized porcine endothelial cells: resistance to complement mediated lysis and down-regulation of VCAM expression induced by low concentrations of polyclonal human IgG antipig antibodies. Transplantation 1996; 62:1127-36. [PMID: 8900314 DOI: 10.1097/00007890-199610270-00018] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The capacity of vascularized xenografts to survive in the face of normal levels of circulating antigraft antibodies and complement has been ascribed to a phenomenon referred to as "endothelial cell accommodation." The mechanisms whereby accommodation might occur have remained obscure. We have investigated this phenomenon in an in vitro system. A preparation of polyclonal immunoglobulin, human normal globulin (HNG), induced a change in the phenotype of immortalized porcine endothelial cells (IPEC) suggestive of accommodation; the cells became resistant to complement mediated lysis and displayed a reduced expression of surface VCAM and MHC class I. The accommodated phenotype only manifested after 72 hr incubation with HNG and was optimal after 120 hr. In an analysis of all the experiments performed, the development of resistance to complement mediated lysis appeared independent of the inducing dose of HNG. However, down-regulation of VCAM was only manifest when subsaturating doses were used. Our results suggest that IgG xenoreactive antibodies can mediate changes in porcine endothelial cell phenotype consistent with accommodation. The dependence on both time and dose of antibody applied might explain why accommodation has been difficult to achieve consistently in in vivo models of discordant xenotransplantation. By demonstrating a functional interaction between human VLA-4 and porcine VCAM, we speculate that the down-regulation in expression of VCAM on accommodated endothelium may have an important regulatory effect on traffic of inflammatory cells into xenografts. Our results have important implications for the development of strategies to promote accommodation of xenografts.
Collapse
Affiliation(s)
- A Dorling
- Department of Immunology, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom
| | | | | | | | | |
Collapse
|
48
|
Zerrahn J, Tiemann F, Deppert W. Simian virus 40 small t antigen activates the carboxyl-terminal transforming p53-binding domain of large T antigen. J Virol 1996; 70:6781-9. [PMID: 8794316 PMCID: PMC190722 DOI: 10.1128/jvi.70.10.6781-6789.1996] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Expression of the simian virus 40 large T antigen (large T) in F111 rat fibroblasts generated only minimal transformants (e.g., F5 cells). Interestingly, F111-derived cells expressing only an amino-terminal fragment of large T spanning amino acids 1 to 147 (e.g., FR3 cells), revealed the same minimal transformed phenotype as F111 cells expressing full-length large T. This suggested that in F5 cells the transforming domain of large T contained within the C-terminal half of the large T molecule, and spanning the p53 binding domain, was not active. Progression to a more transformed phenotype by coexpression of small t antigen (small t) could be achieved in F5 cells but not in FR3 cells. Small-t-induced progression of F5 cells correlated with metabolic stabilization of p53 in complex with large T: whereas in F5 cells the half-life of p53 in complex with large T was only slightly elevated compared with that of (uncomplexed) p53 in parental F111 cells or that in FR3 cells, coexpression of small t in F5 cells led to metabolic stabilization and to high-level accumulation of p53 complexed to large T. In contrast, coexpression of small t had no effect on p53 stabilization or accumulation in FR3 cells. This finding strongly supports the assumption that the mere physical interaction of large T with p53, and thus p53 inactivation, in F5 cells expressing large T only does not reflect the main transforming activity of the C-terminal transforming domain of large T. In contrast, we assume that the transforming potential of this domain requires activation by a cellular function(s) which is mediated by small t and correlates with metabolic stabilization of p53.
Collapse
Affiliation(s)
- J Zerrahn
- Heinrich-Pette-Institut für Experimentelle Virologie und Immunologie an der Universität Hamburg, Germany
| | | | | |
Collapse
|
49
|
Pilon AA, Desjardins P, Hassell JA, Mes-Masson AM. Functional implications of mutations within polyomavirus large T antigen Rb-binding domain: effects on pRb and p107 binding in vitro and immortalization activity in vivo. J Virol 1996; 70:4457-65. [PMID: 8676470 PMCID: PMC190380 DOI: 10.1128/jvi.70.7.4457-4465.1996] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
In this study, we have extensively modified the Rb-binding domain of polyomavirus large T antigen. Mutant polyomavirus large T antigens were tested for their ability to bind pRb and p107 in vitro and assayed for their capacity to immortalize primary rat embryo fibroblasts in vivo. Polyomavirus large T antigen bound pRb and p107 through a common region located between amino acids 141 to 158, containing the consensus Rb-binding sequence D/N-L-X-C-X-E. Substitution of any amino acid within the core Rb-binding sequence abolished pRb and p107 binding in vitro and immortalization activity in vivo. Substitution of amino acids outside the core Rb-binding sequence reduced pRb and p107 binding in vitro and decreased or abolished immortalization of rat embryo fibroblasts in vivo. Although duplication of the Rb-binding domain within the polyomavirus large T antigen results in a molecule that can bind at least twice as much pRb and p107 in vitro, this mutant displayed an essentially wild-type level of immortalization activity. More importantly, we found that the addition of acidic residues within the casein kinase II consensus phosphorylation region flanking the Rb-binding domain, or the deletion of amino acids 256 to 272, increased the immortalizing activity of the mutant polyomavirus large T antigen. These two mutants displayed a greater than wild-type level of pRb binding in vitro, while in contrast, a decreased affinity for p107 binding in vitro was observed. Together, these results indicate that while pRb binding appears to be an essential event for immortalization, there is no tight correlation between the frequency of immortalization and the absolute level of pRb binding in vitro, indicating that other large T antigen functions are important for cellular immortalization.
Collapse
Affiliation(s)
- A A Pilon
- Centre de Recherche Louis-Charles Simard Institut du Cancer de Montréal, Québec, Canada
| | | | | | | |
Collapse
|
50
|
Hopfer U, Woost PG, Jacobberger JW, Douglas JG. New methods for maintaining human renal epithelial cells and analyzing their ion transport functions: potential analysis of genetic disease. ETHNICITY & HEALTH 1996; 1:129-136. [PMID: 9395556 DOI: 10.1080/13557858.1996.9961779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
OBJECTIVES New methods are available to immortalize parenchymal cells from exocrine glands and kidney with retention of differentiation. Adaptation of this technology to small, single-donor biopsy material or surgical specimens could provide genetically homogeneous cells for functional analyses and correlation with genetic background and underlying biochemistry. To develop a methodology useful for renal sodium metabolism, epithelial cell line generation was tested in a hypertensive rat model with features similar to salt-sensitive hypertension in humans. This form of hypertension has a large genetic component and is prevalent in African Americans. DESIGN Protocols were designed to immortalize primary cultures of microdissected proximal tubule epithelial cells from spontaneously hypertensive (SHR) and control, normotensive Wistar-Kyoto (WKY) rats. Immortalization was based on a replication-defective retrovirus coding for SV40 large T-antigen as positive cell cycle regulator. Transport competent cells that grow on porous filters to form confluent monolayers were selected. RESULTS Several proximal tubule cell lines have been developed from SHR and WKY rats. The cells retain important differentiated features, such as epithelial polarity, low monolayer conductance, and sodium-succinate cotransport. They are suitable for analyses of electrolyte transport by electrophysiology or imaging of intracellular fluorescent indicator dyes, such as sodium-binding benzofuran isophthalate. CONCLUSION Feasibility of generating epithelial cell lines from defined renal segments was demonstrated. The cells retain important transport function so that analyses of sodium metabolism and the influence of genetic background on it are possible. The methodology is applicable to human specimens.
Collapse
Affiliation(s)
- U Hopfer
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA
| | | | | | | |
Collapse
|