1
|
Rajabian N, Ikhapoh I, Shahini S, Choudhury D, Thiyagarajan R, Shahini A, Kulczyk J, Breed K, Saha S, Mohamed MA, Udin SB, Stablewski A, Seldeen K, Troen BR, Personius K, Andreadis ST. Methionine adenosyltransferase2A inhibition restores metabolism to improve regenerative capacity and strength of aged skeletal muscle. Nat Commun 2023; 14:886. [PMID: 36797255 PMCID: PMC9935517 DOI: 10.1038/s41467-023-36483-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 02/01/2023] [Indexed: 02/18/2023] Open
Abstract
We investigate the age-related metabolic changes that occur in aged and rejuvenated myoblasts using in vitro and in vivo models of aging. Metabolic and signaling experiments reveal that human senescent myoblasts and myoblasts from a mouse model of premature aging suffer from impaired glycolysis, insulin resistance, and generate Adenosine triphosphate by catabolizing methionine via a methionine adenosyl-transferase 2A-dependant mechanism, producing significant levels of ammonium that may further contribute to cellular senescence. Expression of the pluripotency factor NANOG downregulates methionine adenosyltransferase 2 A, decreases ammonium, restores insulin sensitivity, increases glucose uptake, and enhances muscle regeneration post-injury. Similarly, selective inhibition of methionine adenosyltransferase 2 A activates Akt2 signaling, repairs pyruvate kinase, restores glycolysis, and enhances regeneration, which leads to significant enhancement of muscle strength in a mouse model of premature aging. Collectively, our investigation indicates that inhibiting methionine metabolism may restore age-associated impairments with significant gain in muscle function.
Collapse
Affiliation(s)
- Nika Rajabian
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Izuagie Ikhapoh
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Shahryar Shahini
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Debanik Choudhury
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Ramkumar Thiyagarajan
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo and Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - Aref Shahini
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Joseph Kulczyk
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Kendall Breed
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Shilpashree Saha
- Department of Biomedical Engineering, University at Buffalo, Amherst, NY, USA
| | - Mohamed Alaa Mohamed
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA
| | - Susan B Udin
- Department of Physiology and Biophysics, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Aimee Stablewski
- Gene Targeting and Transgenic Shared Resource, Roswell Park Comprehensive Cancer Institute, Buffalo, NY, USA
| | - Kenneth Seldeen
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo and Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - Bruce R Troen
- Division of Geriatrics and Palliative Medicine, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo and Research Service, Veterans Affairs Western New York Healthcare System, Buffalo, NY, USA
| | - Kirkwood Personius
- Department of Rehabilitation Science, School of Public Health and Health Professions, University at Buffalo, Buffalo, NY, USA
| | - Stelios T Andreadis
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, NY, USA.
- Department of Biomedical Engineering, University at Buffalo, Amherst, NY, USA.
- Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY, USA.
- Cell, Gene and Tissue Engineering (CGTE) Center, School of Engineering and Applied Sciences, University at Buffalo, Amherst, NY, USA.
| |
Collapse
|
2
|
Kim SG, Lee S, Kim Y, Park J, Woo D, Kim D, Li Y, Shin W, Kang H, Yook C, Lee M, Kim K, Roh JD, Ryu J, Jung H, Um SM, Yang E, Kim H, Han J, Heo WD, Kim E. Tanc2-mediated mTOR inhibition balances mTORC1/2 signaling in the developing mouse brain and human neurons. Nat Commun 2021; 12:2695. [PMID: 33976205 PMCID: PMC8113471 DOI: 10.1038/s41467-021-22908-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 04/07/2021] [Indexed: 12/27/2022] Open
Abstract
mTOR signaling, involving mTORC1 and mTORC2 complexes, critically regulates neural development and is implicated in various brain disorders. However, we do not fully understand all of the upstream signaling components that can regulate mTOR signaling, especially in neurons. Here, we show a direct, regulated inhibition of mTOR by Tanc2, an adaptor/scaffolding protein with strong neurodevelopmental and psychiatric implications. While Tanc2-null mice show embryonic lethality, Tanc2-haploinsufficient mice survive but display mTORC1/2 hyperactivity accompanying synaptic and behavioral deficits reversed by mTOR-inhibiting rapamycin. Tanc2 interacts with and inhibits mTOR, which is suppressed by mTOR-activating serum or ketamine, a fast-acting antidepressant. Tanc2 and Deptor, also known to inhibit mTORC1/2 minimally affecting neurodevelopment, distinctly inhibit mTOR in early- and late-stage neurons. Lastly, Tanc2 inhibits mTORC1/2 in human neural progenitor cells and neurons. In summary, our findings show that Tanc2 is a mTORC1/2 inhibitor affecting neurodevelopment.
Collapse
Affiliation(s)
- Sun-Gyun Kim
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | - Suho Lee
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | - Yangsik Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon, Korea
| | - Jieun Park
- Department of Biological Sciences, KAIST, Daejeon, Korea
| | - Doyeon Woo
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Korea
| | - Dayeon Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon, Korea
| | - Yan Li
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | - Wangyong Shin
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | - Hyunjeong Kang
- Department of Biological Sciences, KAIST, Daejeon, Korea
| | - Chaehyun Yook
- Department of Biological Sciences, KAIST, Daejeon, Korea
| | - Minji Lee
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Korea
| | - Kyungdeok Kim
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | | | - Jeseung Ryu
- Department of Biological Sciences, KAIST, Daejeon, Korea
| | - Hwajin Jung
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea
| | - Seung Min Um
- Department of Biological Sciences, KAIST, Daejeon, Korea
| | - Esther Yang
- Department of Anatomy and Division of Brain Korea 21, Biomedical Science, College of Medicine, Korea University, Seoul, Korea
| | - Hyun Kim
- Department of Anatomy and Division of Brain Korea 21, Biomedical Science, College of Medicine, Korea University, Seoul, Korea
| | - Jinju Han
- Graduate School of Medical Science and Engineering, Korea Advanced Institute for Science and Technology (KAIST), Daejeon, Korea
| | - Won Do Heo
- Department of Biological Sciences, KAIST, Daejeon, Korea
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, Korea
| | - Eunjoon Kim
- Center for Synaptic Brain Dysfunctions, Institute for Basic Science (IBS), Daejeon, Korea.
- Department of Biological Sciences, KAIST, Daejeon, Korea.
| |
Collapse
|
3
|
Hall MS, Decker JT, Shea LD. Towards systems tissue engineering: Elucidating the dynamics, spatial coordination, and individual cells driving emergent behaviors. Biomaterials 2020; 255:120189. [PMID: 32569865 PMCID: PMC7396312 DOI: 10.1016/j.biomaterials.2020.120189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 04/20/2020] [Accepted: 06/09/2020] [Indexed: 12/11/2022]
Abstract
Biomaterial systems have enabled the in vitro production of complex, emergent tissue behaviors that were not possible with conventional two-dimensional culture systems, allowing for analysis of both normal development and disease processes. We propose that the path towards developing the design parameters for biomaterial systems lies with identifying the molecular drivers of emergent behavior through leveraging technological advances in systems biology, including single cell omics, genetic engineering, and high content imaging. This growing research opportunity at the intersection of the fields of tissue engineering and systems biology - systems tissue engineering - can uniquely interrogate the mechanisms by which complex tissue behaviors emerge with the potential to capture the contribution of i) dynamic regulation of tissue development and dysregulation, ii) single cell heterogeneity and the function of rare cell types, and iii) the spatial distribution and structure of individual cells and cell types within a tissue. By leveraging advances in both biological and materials data science, systems tissue engineering can facilitate the identification of biomaterial design parameters that will accelerate basic science discovery and translation.
Collapse
Affiliation(s)
- Matthew S Hall
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Joseph T Decker
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Lonnie D Shea
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
4
|
Roelse M, Henquet MGL, Verhoeven HA, de Ruijter NCA, Wehrens R, van Lenthe MS, Witkamp RF, Hall RD, Jongsma MA. Calcium Imaging of GPCR Activation Using Arrays of Reverse Transfected HEK293 Cells in a Microfluidic System. SENSORS 2018; 18:s18020602. [PMID: 29462903 PMCID: PMC5855233 DOI: 10.3390/s18020602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 02/06/2018] [Accepted: 02/12/2018] [Indexed: 11/16/2022]
Abstract
Reverse-transfected cell arrays in microfluidic systems have great potential to perform large-scale parallel screening of G protein-coupled receptor (GPCR) activation. Here, we report the preparation of a novel platform using reverse transfection of HEK293 cells, imaging by stereo-fluorescence microscopy in a flowcell format, real-time monitoring of cytosolic calcium ion fluctuations using the fluorescent protein Cameleon and analysis of GPCR responses to sequential sample exposures. To determine the relationship between DNA concentration and gene expression, we analyzed cell arrays made with variable concentrations of plasmid DNA encoding fluorescent proteins and the Neurokinin 1 (NK1) receptor. We observed pronounced effects on gene expression of both the specific and total DNA concentration. Reverse transfected spots with NK1 plasmid DNA at 1% of total DNA still resulted in detectable NK1 activation when exposed to its ligand. By varying the GPCR DNA concentration in reverse transfection, the sensitivity and robustness of the receptor response for sequential sample exposures was optimized. An injection series is shown for an array containing the NK1 receptor, bitter receptor TAS2R8 and controls. Both receptors were exposed 14 times to alternating samples of two ligands. Specific responses remained reproducible. This platform introduces new opportunities for high throughput screening of GPCR libraries.
Collapse
Affiliation(s)
- Margriet Roelse
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
- Laboratory of Plant Physiology, Wageningen University and Research, 6708 PB Wageningen, The Netherlands.
| | - Maurice G L Henquet
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
| | - Harrie A Verhoeven
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
| | - Norbert C A de Ruijter
- Laboratory of Cell Biology, Wageningen University and Research, 6708 PB Wageningen, The Netherlands.
| | - Ron Wehrens
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
- BU Biometris, Wageningen University and Research, 6708 PB Wageningen, The Netherlands.
| | - Marco S van Lenthe
- BU Biometris, Wageningen University and Research, 6708 PB Wageningen, The Netherlands.
| | - Renger F Witkamp
- Human Nutrition and Health, Wageningen University and Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands.
| | - Robert D Hall
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
- Laboratory of Plant Physiology, Wageningen University and Research, 6708 PB Wageningen, The Netherlands.
| | - Maarten A Jongsma
- BU Bioscience, Wageningen University and Research, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
| |
Collapse
|
5
|
Kim HC, Heo JY, Lee TK, Cho SG, Kwon YJ. Optimization of Cell-Based cDNA Microarray Conditions for Gene Functional Studies in HEK293 Cells. SLAS DISCOVERY 2017; 22:1053-1059. [PMID: 28324659 DOI: 10.1177/2472555217699823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Since the cell-based cDNA microarray (CBCM) technique has been a useful tool for gain-of-function studies, many investigators have used CBCMs to identify interesting genes. However, this method requires better-established conditions to ensure high reverse transfection efficiency without cross-contamination. Therefore, we optimized CBCM techniques through various means. We determined that Lipofectamine 2000 was the most appropriate transfection reagent by evaluating eight commercialized reagents, and we determined that the most effective concentrations for printing solution constituents were 0.2 M sucrose (to yield a final concentration of 32 mM) and 0.2% gelatin (to yield a final concentration 0.075%). After examining various combinations, we also determined that the best concentrations of cDNA and transfection reagent for optimal reverse transfection efficiency were 1.5 µg/5 µL of cDNA and 5.5 µL of Lipofectamine 2000. Finally, via a time course, we determined that 72 h was the most effective reaction duration for reverse transfection, and we confirmed the stability of cDNA spot activity of CBCMs for various storage periods. In summary, the CBCM conditions that we have identified can provide more effective outcomes for cDNA reverse transfection on microarrays.
Collapse
Affiliation(s)
- Hi Chul Kim
- 1 Institut Pasteur Korea, Gyeonggi-do, Republic of Korea.,2 Department of Animal Biotechnology and Incurable Disease Animal Model & Stem Cell Institute (IDASI), Konkuk University, Seoul, Republic of Korea
| | - Jin Yeong Heo
- 1 Institut Pasteur Korea, Gyeonggi-do, Republic of Korea
| | - Tae-Kyu Lee
- 1 Institut Pasteur Korea, Gyeonggi-do, Republic of Korea
| | - Ssang-Goo Cho
- 2 Department of Animal Biotechnology and Incurable Disease Animal Model & Stem Cell Institute (IDASI), Konkuk University, Seoul, Republic of Korea
| | - Yong-Jun Kwon
- 1 Institut Pasteur Korea, Gyeonggi-do, Republic of Korea.,3 Ksilink, Strasbourg, France
| |
Collapse
|
6
|
Kim HC, Shum D, Seol HS, Jang SJ, Cho SG, Kwon YJ. Development of Cell-Defined Lentivirus-Based Microarray for Mammalian Cells. SLAS DISCOVERY 2016; 22:108-113. [PMID: 27703081 DOI: 10.1177/1087057116672417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Although reverse transfection cell microarray (RTCM) is a powerful tool for mammalian cell studies, the technique is not appropriate for cells that are difficult to transfect. The lentivirus-infected cell microarray (LICM) technique was designed to improve overall efficiency. However, LICM presents new challenges because individual lentiviral particles can spread through the cell population, leading to cross-contamination. Therefore, we designed a cell-defined lentivirus microarray (CDLM) technique using cell-friendly biomaterials that are controlled by cell attachment timing. We selected poly-l-lysine (PLL) with Matrigel as the best combination of biomaterials for cell-defined culture. We used 2 µL PLL to determine by titration the optimum concentration required (0.04% stock, 0.005% final concentration). We also determined the optimum concentration of 10 µL of lentivirus particles for maximum reverse infection efficiency (1 × 108 infectious units [IFU]/mL stock, 62.5% final concentration) and established the best combination of components for the lentivirus mixture (10 µL of lentivirus particles and 2 µL each of siGLO Red dye, Matrigel, and 0.04% PLL). Finally, we validated both the effect of reverse infection in various cell lines and lentivirus spot activity in CDLM by storage period. This method provides an effective lentivirus-infected cell microarray for large-scale gene function studies.
Collapse
Affiliation(s)
- Hi Chul Kim
- 1 Institut Pasteur Korea, IP-Korea, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea.,2 Department of Animal Biotechnology and Incurable Disease Animal Model & Stem Cell Institute (IDASI), Konkuk University, Seoul, Republic of Korea
| | - David Shum
- 1 Institut Pasteur Korea, IP-Korea, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea
| | - Hyang Sook Seol
- 3 Asan Institute for Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Se Jin Jang
- 3 Asan Institute for Life Science, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Ssang-Goo Cho
- 2 Department of Animal Biotechnology and Incurable Disease Animal Model & Stem Cell Institute (IDASI), Konkuk University, Seoul, Republic of Korea
| | - Yong-Jun Kwon
- 1 Institut Pasteur Korea, IP-Korea, Bundang-gu, Seongnam-si, Gyeonggi-do, Republic of Korea.,Ksilink, 16, Rue d'Ankara 67000 Strasbourg, France
| |
Collapse
|
7
|
Interaction between integrin α5 and PDE4D regulates endothelial inflammatory signalling. Nat Cell Biol 2016; 18:1043-53. [PMID: 27595237 PMCID: PMC5301150 DOI: 10.1038/ncb3405] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 08/03/2016] [Indexed: 12/16/2022]
Abstract
Atherosclerosis is primarily a disease of lipid metabolism and inflammation; however, it is also closely associated with endothelial extracellular matrix (ECM) remodelling, with fibronectin accumulating in the laminin-collagen basement membrane. To investigate how fibronectin modulates inflammation in arteries, we replaced the cytoplasmic tail of the fibronectin receptor integrin α5 with that of the collagen/laminin receptor integrin α2. This chimaera suppressed inflammatory signalling in endothelial cells on fibronectin and in knock-in mice. Fibronectin promoted inflammation by suppressing anti-inflammatory cAMP. cAMP was activated through endothelial prostacyclin secretion; however, this was ECM-independent. Instead, cells on fibronectin suppressed cAMP via enhanced phosphodiesterase (PDE) activity, through direct binding of integrin α5 to phosphodiesterase-4D5 (PDE4D5), which induced PP2A-dependent dephosphorylation of PDE4D5 on the inhibitory site Ser651. In vivo knockdown of PDE4D5 inhibited inflammation at athero-prone sites. These data elucidate a molecular mechanism linking ECM remodelling and inflammation, thereby identifying a new class of therapeutic targets.
Collapse
|
8
|
Mistriotis P, Bajpai VK, Wang X, Rong N, Shahini A, Asmani M, Liang MS, Wang J, Lei P, Liu S, Zhao R, Andreadis ST. NANOG Reverses the Myogenic Differentiation Potential of Senescent Stem Cells by Restoring ACTIN Filamentous Organization and SRF-Dependent Gene Expression. Stem Cells 2016; 35:207-221. [PMID: 27350449 DOI: 10.1002/stem.2452] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 05/28/2016] [Indexed: 12/12/2022]
Abstract
Cellular senescence as a result of organismal aging or progeroid diseases leads to stem cell pool exhaustion hindering tissue regeneration and contributing to the progression of age related disorders. Here we discovered that ectopic expression of the pluripotent factor NANOG in senescent or progeroid myogenic progenitors reversed cellular aging and restored completely the ability to generate contractile force. To elicit its effects, NANOG enabled reactivation of the ROCK and Transforming Growth Factor (TGF)-β pathways-both of which were impaired in senescent cells-leading to ACTIN polymerization, MRTF-A translocation into the nucleus and serum response factor (SRF)-dependent myogenic gene expression. Collectively our data reveal that cellular senescence can be reversed and provide a novel strategy to regain the lost function of aged stem cells without reprogramming to the pluripotent state. Stem Cells 2017;35:207-221.
Collapse
Affiliation(s)
- Panagiotis Mistriotis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Vivek K Bajpai
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Xiaoyan Wang
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Na Rong
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Aref Shahini
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Mohammadnabi Asmani
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Mao-Shih Liang
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Jianmin Wang
- Department of Biostatistics and Bioinformatics, Roswell Park Cancer Institute, Buffalo, New York, USA
| | - Pedro Lei
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Song Liu
- Department of Biostatistics and Bioinformatics, Roswell Park Cancer Institute, Buffalo, New York, USA
| | - Ruogang Zhao
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Stelios T Andreadis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA.,Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, New York, USA
| |
Collapse
|
9
|
Moharil J, Lei P, Tian J, Gaile DP, Andreadis ST. Lentivirus Live Cell Array for Quantitative Assessment of Gene and Pathway Activation during Myogenic Differentiation of Mesenchymal Stem Cells. PLoS One 2015; 10:e0141365. [PMID: 26505747 PMCID: PMC4624764 DOI: 10.1371/journal.pone.0141365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 10/06/2015] [Indexed: 11/19/2022] Open
Abstract
Stem cell differentiation involves multiple cascades of transcriptional regulation that govern the cell fate. To study the real-time dynamics of this complex process, quantitative and high throughput live cell assays are required. Herein, we developed a lentiviral library of promoters and transcription factor binding sites to quantitatively capture the gene expression dynamics over a period of several days during myogenic differentiation of human mesenchymal stem cells (MSCs) harvested from two different anatomic locations, bone marrow and hair follicle. Our results enabled us to monitor the sequential activation of signaling pathways and myogenic gene promoters at various stages of differentiation. In conjunction with chemical inhibitors, the lentiviral array (LVA) results also revealed the relative contribution of key signaling pathways that regulate the myogenic differentiation. Our study demonstrates the potential of LVA to monitor the dynamics of gene and pathway activation during MSC differentiation as well as serve as a platform for discovery of novel molecules, genes and pathways that promote or inhibit complex biological processes.
Collapse
Affiliation(s)
- Janhavi Moharil
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, 908 Furnas Hall, Amherst, NY 14260–4200, United States of America
- Department of Biostatistics, University at Buffalo, State University of New York, Kimball, Buffalo, NY 14214–3000, United States of America
| | - Pedro Lei
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, 908 Furnas Hall, Amherst, NY 14260–4200, United States of America
| | - Jun Tian
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, 908 Furnas Hall, Amherst, NY 14260–4200, United States of America
| | - Daniel P. Gaile
- Department of Biostatistics, University at Buffalo, State University of New York, Kimball, Buffalo, NY 14214–3000, United States of America
| | - Stelios T. Andreadis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, 908 Furnas Hall, Amherst, NY 14260–4200, United States of America
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Amherst, NY 14260–4200, United States of America
- Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY 14203, United States of America
- * E-mail:
| |
Collapse
|
10
|
Alimperti S, Andreadis ST. CDH2 and CDH11 act as regulators of stem cell fate decisions. Stem Cell Res 2015; 14:270-82. [PMID: 25771201 DOI: 10.1016/j.scr.2015.02.002] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 01/24/2015] [Accepted: 02/10/2015] [Indexed: 12/14/2022] Open
Abstract
Accumulating evidence suggests that the mechanical and biochemical signals originating from cell-cell adhesion are critical for stem cell lineage specification. In this review, we focus on the role of cadherin mediated signaling in development and stem cell differentiation, with emphasis on two well-known cadherins, cadherin-2 (CDH2) (N-cadherin) and cadherin-11 (CDH11) (OB-cadherin). We summarize the existing knowledge regarding the role of CDH2 and CDH11 during development and differentiation in vivo and in vitro. We also discuss engineering strategies to control stem cell fate decisions by fine-tuning the extent of cell-cell adhesion through surface chemistry and microtopology. These studies may be greatly facilitated by novel strategies that enable monitoring of stem cell specification in real time. We expect that better understanding of how intercellular adhesion signaling affects lineage specification may impact biomaterial and scaffold design to control stem cell fate decisions in three-dimensional context with potential implications for tissue engineering and regenerative medicine.
Collapse
Affiliation(s)
- Stella Alimperti
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | - Stelios T Andreadis
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA; Center of Excellence in Bioinformatics and Life Sciences, Buffalo, NY 14203, USA.
| |
Collapse
|
11
|
Sridharan GV, Choi K, Klemashevich C, Wu C, Prabakaran D, Pan LB, Steinmeyer S, Mueller C, Yousofshahi M, Alaniz RC, Lee K, Jayaraman A. Prediction and quantification of bioactive microbiota metabolites in the mouse gut. Nat Commun 2014; 5:5492. [DOI: 10.1038/ncomms6492] [Citation(s) in RCA: 164] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 10/07/2014] [Indexed: 12/22/2022] Open
|
12
|
Padmashali RM, Mistriotis P, Liang MS, Andreadis ST. Lentiviral arrays for live-cell dynamic monitoring of gene and pathway activity during stem cell differentiation. Mol Ther 2014; 22:1971-82. [PMID: 24895998 DOI: 10.1038/mt.2014.103] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 05/02/2014] [Indexed: 02/07/2023] Open
Abstract
Uncovering the complexity of mesenchymal stem cell (MSC) differentiation requires novel methods to capture the dynamics of the process in a quantitative and high-throughput manner. To this end, we developed a lentiviral array (LVA) of reporters to capture the dynamics of gene and pathway activity during MSC differentiation into adipogenic, chondrogenic, and osteogenic lineages. Our results identified signature promoters and pathways with unique activation profile for each MSC lineage. In combination with chemical inhibitors, lineage-specific reporters predicted the effects of signaling pathway perturbations on MSC differentiation. Interestingly, some pathways were critical for differentiation into all lineages, while others had differential effects on each lineage. Our study suggests that when combined with large chemical or siRNA libraries, the reporter LVA can be used to uncover novel genes and signaling pathways affecting complex biological processes such as stem cell differentiation or reprogramming.
Collapse
Affiliation(s)
- Roshan M Padmashali
- Department of Chemical and Biological Engineering, Bioengineering Laboratory, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Panagiotis Mistriotis
- Department of Chemical and Biological Engineering, Bioengineering Laboratory, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Mao-shih Liang
- Department of Chemical and Biological Engineering, Bioengineering Laboratory, University at Buffalo, The State University of New York, Amherst, New York, USA
| | - Stelios T Andreadis
- 1] Department of Chemical and Biological Engineering, Bioengineering Laboratory, University at Buffalo, The State University of New York, Amherst, New York, USA [2] Department of Biomedical Engineering, University at Buffalo, The State University of New York, New York, Amherst, USA [3] Center of Excellence in Bioinformatics and Life Sciences, Buffalo, New York, USA
| |
Collapse
|
13
|
Rehmann MS, Kloxin AM. Tunable and dynamic soft materials for three-dimensional cell culture. SOFT MATTER 2013; 9:6737-6746. [PMID: 23930136 PMCID: PMC3733394 DOI: 10.1039/c3sm50217a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 03/01/2013] [Indexed: 05/14/2023]
Abstract
The human body is complex and hierarchically structured, composed of cells residing within the extracellular matrix (ECM) of tissues that are assembled into organs, all working together to complete a given function. One goal of current biomaterials research is to capture some of this complexity outside of the body for understanding the underlying biology of development, repair, and disease and to devise new strategies for regenerative medicine or disease treatment. Polymeric materials have arisen as powerful tools to mimic the native ECM, giving experimenters a way to capture key aspects of the native cellular environment outside of the body. In particular, dynamic materials allow changes in the properties of these ECM mimics during an experiment, affording an additional degree of control for the experimenter. In this tutorial review, the basic cellular processes of cell migration, proliferation, and differentiation will be overviewed to motivate design considerations for polymeric ECM mimics, and examples will be given of how classes of dynamic materials are being used to study each cellular process.
Collapse
Affiliation(s)
- Matthew S. Rehmann
- Department of Chemical & Biomolecular Engineering , University of Delaware , Newark , DE 19716 , USA .
| | - April M. Kloxin
- Department of Chemical & Biomolecular Engineering , University of Delaware , Newark , DE 19716 , USA .
- Department of Materials Science & Engineering , University of Delaware , Newark , DE 19716 , USA
| |
Collapse
|
14
|
Pol SU, Lang JK, O'Bara MA, Cimato TR, McCallion AS, Sim FJ. Sox10-MCS5 enhancer dynamically tracks human oligodendrocyte progenitor fate. Exp Neurol 2013; 247:694-702. [PMID: 23507034 DOI: 10.1016/j.expneurol.2013.03.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 03/05/2013] [Accepted: 03/08/2013] [Indexed: 10/27/2022]
Abstract
In this study, we sought to establish a novel method to prospectively and dynamically identify live human oligodendrocyte precursor cells (OPCs) and oligodendrocyte lineage cells from brain dissociates and pluripotent stem cell culture. We selected a highly conserved enhancer element of the Sox10 gene, known as MCS5, which directs reporter expression to oligodendrocyte lineage cells in mouse and zebrafish. We demonstrate that lentiviral Sox10-MCS5 induced expression of GFP at high levels in a subpopulation of human CD140a/PDGFαR-sorted OPCs as well as their immature oligodendrocyte progeny. Furthermore, we show that almost all Sox10-MCS5:GFP(high) cells expressed OPC antigen CD140a and human OPCs expressing SOX10, OLIG2, and PDGFRA mRNAs could be prospectively identified using GFP based fluorescence activated cells sorting alone. Additionally, we established a human induced pluripotent cell (iPSC) line transduced with the Sox10-MCS5:GFP reporter using a Rex-Neo cassette. Similar to human primary cells, GFP expression was restricted to embryoid bodies containing both oligodendrocyte progenitor and oligodendrocyte cells and co-localized with NG2 and O4-positive cells respectively. As such, we have developed a novel reporter system that can track oligodendrocyte commitment in human cells, establishing a valuable tool to improve our understanding and efficiency of human oligodendrocyte derivation.
Collapse
Affiliation(s)
- Suyog U Pol
- Department of Pharmacology, School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, NY 14214, USA
| | | | | | | | | | | |
Collapse
|
15
|
Alimperti S, Lei P, Tian J, Andreadis ST. A novel lentivirus for quantitative assessment of gene knockdown in stem cell differentiation. Gene Ther 2012; 19:1123-32. [PMID: 22241174 DOI: 10.1038/gt.2011.208] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 09/26/2011] [Accepted: 10/10/2011] [Indexed: 01/19/2023]
Abstract
Loss of gene function is a valuable tool for screening genes in cellular processes including stem cell differentiation differentiation. However, the criteria for evaluating gene knockdown are usually based on end-point analysis and real-time, dynamic information is lacking. To overcome these limitations, we engineered a shRNA encoding LentiViral Dual Promoter vector (shLVDP) that enabled real-time monitoring of mesenchymal stem (MSC) differentiation and simultaneous gene knockdown. In this vector, the activity of the alpha-smooth muscle actin (αSMA) promoter was measured by the expression of a destabilized green fluorescent protein, and was used as an indicator of myogenic differentiation; constitutive expression of discosoma red fluorescent protein was used to measure transduction efficiency and to normalize αSMA promoter activity; and shRNA was encoded by a doxycycline (Dox)-regulatable H1 promoter. Importantly, the normalized promoter activity was independent of lentivirus titer allowing quantitative assessment of gene knockdown. Using this vector, we evaluated 11 genes in the TGF-β1 or Rho signaling pathway on SMC maturation and on MSC differentiation along the myogenic lineage. As expected, knockdown of genes such as Smad2/3 or RhoA inhibited myogenic differentiation, while knocking down the myogenic differentiation inhibitor, Klf4, increased αSMA promoter activity significantly. Notably, some genes for example, Smad7 or KLF4 showed differential regulation of myogenic differentiation in MSC from different anatomic locations such as bone marrow and hair follicles. Finally, Dox-regulatable shRNA expression enabled temporal control of gene knockdown and provided dynamic information on the effect of different genes on myogenic phenotype. Our data suggests that shLVDP may be ideal for development of lentiviral microarrays to decipher gene regulatory networks of complex biological processes such as stem cell differentiation or reprogramming.
Collapse
Affiliation(s)
- S Alimperti
- Bioengineering Laboratory, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14072, USA
| | | | | | | |
Collapse
|
16
|
Gao S, Seker E, Casali M, Wang F, Bale SS, Price GM, Yarmush ML. Ex vivo gene delivery to hepatocytes: techniques, challenges, and underlying mechanisms. Ann Biomed Eng 2012; 40:1851-61. [PMID: 22484829 PMCID: PMC3901163 DOI: 10.1007/s10439-012-0555-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 03/19/2012] [Indexed: 01/01/2023]
Abstract
Gene delivery to primary hepatocytes is an important tool for a number of applications including the study of liver cell biology and pathology, drug screening, and gene therapy. Robust transfection of primary hepatocytes, however, is significantly more difficult to achieve than in cell lines or readily dividing primary cells. In this report, we investigated in vitro gene delivery to both primary rat hepatocytes and Huh7.5.1 cells (a hepatoma cell line) using a number of viral and non-viral methods, including Lipofectamine 2000, FuGene HD, Nucleofection, Magnetofection, and lentiviruses. Our results showed that Lipofectamine 2000 is the most efficient reagent for green fluorescent protein (GFP) gene delivery to primary rat hepatocytes (33.3 ± 1.8% transfection efficiency) with minimal adverse effect on several hepatic functions, such as urea and albumin secretion. The lentiviral vectors used in this study exhibited undetectable gene delivery to primary rat hepatocytes but significant delivery to Huh7.5.1 cells (>80% transfection efficiency). In addition, we demonstrated lentiviral-based and spatially defined delivery of the GFP gene to Huh7.5.1 cells for use in biological microelectromechanical systems.
Collapse
Affiliation(s)
- Shan Gao
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
| | - Erkin Seker
- Department of Electrical and Computer Engineering, University of California Davis, Davis, CA 95616, USA
| | - Monica Casali
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
| | - Fangjing Wang
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
| | - Shyam Sundhar Bale
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
| | - Gavrielle M. Price
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
| | - Martin L. Yarmush
- Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School and Shriners Hospitals for Children, 51 Blossom Street, Boston, MA 02114, USA
- Department of Biomedical Engineering, Rutgers University, Piscataway, NJ 08854, USA
| |
Collapse
|
17
|
Underhill GH. Stem cell bioengineering at the interface of systems-based models and high-throughput platforms. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2012; 4:525-45. [DOI: 10.1002/wsbm.1189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
18
|
Titmarsh DM, Chen H, Wolvetang EJ, Cooper-White JJ. Arrayed cellular environments for stem cells and regenerative medicine. Biotechnol J 2012; 8:167-79. [PMID: 22890848 DOI: 10.1002/biot.201200149] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 07/02/2012] [Accepted: 07/17/2012] [Indexed: 12/26/2022]
Abstract
The behavior and composition of both multipotent and pluripotent stem cell populations are exquisitely controlled by a complex, spatiotemporally variable interplay of physico-chemical, extracellular matrix, cell-cell interaction, and soluble factor cues that collectively define the stem cell niche. The push for stem cell-based regenerative medicine models and therapies has fuelled demands for increasingly accurate cellular environmental control and enhanced experimental throughput, driving an evolution of cell culture platforms away from conventional culture formats toward integrated systems. Arrayed cellular environments typically provide a set of discrete experimental elements with variation of one or several classes of stimuli across elements of the array. These are based on high-content/high-throughput detection, small sample volumes, and multiplexing of environments to increase experimental parameter space, and can be used to address a range of biological processes at the cell population, single-cell, or subcellular level. Arrayed cellular environments have the capability to provide an unprecedented understanding of the molecular and cellular events that underlie expansion and specification of stem cell and therapeutic cell populations, and thus generate successful regenerative medicine outcomes. This review focuses on recent key developments of arrayed cellular environments and their contribution and potential in stem cells and regenerative medicine.
Collapse
Affiliation(s)
- Drew M Titmarsh
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St. Lucia, Australia
| | | | | | | |
Collapse
|
19
|
Abstract
In the past decade, the tendency to move from a global, one-size-fits-all treatment philosophy to personalized medicine is based, in part, on the nuanced differences and sub-classifications of disease states. Our knowledge of these varied states stems from not only the ability to diagnose, classify, and perform experiments on cell populations as a whole, but also from new technologies that allow interrogation of cell populations at the individual cell level. Such departures from conventional thinking are driven by the recognition that clonal cell populations have numerous activities that manifest as significant levels of non-genetic heterogeneity. Clonal populations by definition originate from a single genetic origin so are regarded as having a high level of homogeneity as compared to genetically distinct cell populations. However, analysis at the single cell level has revealed a different phenomenon; cells and organisms require an inherent level of non-genetic heterogeneity to function properly, and in some cases, to survive. The growing understanding of this occurrence has lead to the development of methods to monitor, analyze, and better characterize the heterogeneity in cell populations. Following the trend of DNA- and protein microarrays, platforms capable of simultaneously monitoring each cell in a population have been developed. These cellular microarray platforms and other related formats allow for continuous monitoring of single live cells and simultaneously generate individual cell and average population data that are more descriptive and information-rich than traditional bulk methods. These technological advances have helped develop a better understanding of the intricacies associated with biological processes and afforded greater insight into complex biological systems. The associated instruments, techniques, and reagents now allow for highly multiplexed analyses, which enable multiple cellular activities, processes, or pathways to be monitored simultaneously. This critical review will discuss the paradigm shift associated with cellular heterogeneity, speak to the key developments that have lead to our better understanding of systems biology, and detail the future directions of the discipline (281 references).
Collapse
Affiliation(s)
- Maureen A Walling
- Department of Chemistry, University at Albany, SUNY, 1400 Washington Ave., Albany, NY 12222, USA
| | | |
Collapse
|
20
|
Padmashali RM, Andreadis ST. Engineering fibrinogen-binding VSV-G envelope for spatially- and cell-controlled lentivirus delivery through fibrin hydrogels. Biomaterials 2011; 32:3330-9. [PMID: 21296411 DOI: 10.1016/j.biomaterials.2011.01.035] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 01/13/2011] [Indexed: 01/20/2023]
Abstract
We recently demonstrated that fibrin hydrogels can be used as vehicles for efficient lentivirus gene delivery. Gene transfer in fibrin gels was strongly dependent on matrix degradation by target cells but a fraction of lentiviral particles diffused out of the gels over time compromising spatial control of gene transfer. To overcome this challenge, we engineered lentiviral particles that bind covalently to fibrin during polymerization. To this end, we fused into the viral envelope glycoprotein (VSV-G) peptide domains that are recognized by factor XIII and protease cleavage sites that are recognized by plasmin. Lentivirus pseudotyped with the modified envelopes bound to fibrinogen in a factor XIII dose dependent manner and was released upon plasmin treatment. The peptide/VSV-G fusion envelope variants did not compromise the transduction efficiency of the resulting virus except when lacking any flexible linkers separating the peptide from the VSV-G envelope. Diffusion of virus from the gels decreased dramatically, especially at high concentrations of FXIII, even for fibrin gels with low fibrinogen concentration that were loaded with high titer virus. Lentivirus arrays prepared with fibrin-conjugated lentivirus yielded highly efficient gene transfer that was confined to virus-containing fibrin spots. As a result, signal/noise ratio increased and cross-contamination between neighboring sites was minimal. Finally, in addition to lentivirus microarrays this strategy may be used to achieve spatially-controlled gene transfer for therapeutic applications.
Collapse
Affiliation(s)
- Roshan M Padmashali
- Bioengineering Laboratory, 908 Furnas Hall, Department of Chemical and Biological Engineering, University at Buffalo, State University of New York, Amherst, NY 14260-4200, USA
| | | |
Collapse
|