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Kudelka MR, Gu W, Matsumoto Y, Ju T, Barnes II RH, Kardish RJ, Heimburg-Molinaro J, Lehoux S, Zeng J, Cohen C, Robinson BS, Shah KS, Chaikof EL, Stowell SR, Cummings RD. Targeting altered glycosylation in secreted tumor glycoproteins for broad cancer detection. Glycobiology 2023; 33:567-578. [PMID: 37216646 PMCID: PMC10426321 DOI: 10.1093/glycob/cwad035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 03/23/2023] [Indexed: 05/24/2023] Open
Abstract
There is an urgent need to develop new tumor biomarkers for early cancer detection, but the variability of tumor-derived antigens has been a limitation. Here we demonstrate a novel anti-Tn antibody microarray platform to detect Tn+ glycoproteins, a near universal antigen in carcinoma-derived glycoproteins, for broad detection of cancer. The platform uses a specific recombinant IgG1 to the Tn antigen (CD175) as a capture reagent and a recombinant IgM to the Tn antigen as a detecting reagent. These reagents were validated by immunohistochemistry in recognizing the Tn antigen using hundreds of human tumor specimens. Using this approach, we could detect Tn+ glycoproteins at subnanogram levels using cell lines and culture media, serum, and stool samples from mice engineered to express the Tn antigen in intestinal epithelial cells. The development of a general cancer detection platform using recombinant antibodies for detection of altered tumor glycoproteins expressing a unique antigen could have a significant impact on cancer detection and monitoring.
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Affiliation(s)
- Matthew R Kudelka
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30033, United States
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Wei Gu
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Yasuyuki Matsumoto
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Tongzhong Ju
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30033, United States
| | - Richard H Barnes II
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Robert J Kardish
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Jamie Heimburg-Molinaro
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Sylvain Lehoux
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Junwei Zeng
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Cynthia Cohen
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30033, United States
| | - Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30033, United States
| | - Kinjal S Shah
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30033, United States
| | - Elliot L Chaikof
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
| | - Sean R Stowell
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30033, United States
| | - Richard D Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, United States
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2
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Ware MB, Phillips M, McQuinn C, Zaidi MY, Knochelmann HM, Greene E, Robinson BS, Herting CJ, Mace TA, Chen Z, Zhang C, Farren MR, Ruggieri AN, Bowers JS, Shakya R, Farris AB, Young G, Carson Iii WE, El-Rayes B, Paulos CM, Lesinski GB. Dual IL-6 and CTLA-4 blockade regresses pancreatic tumors in a T cell and CXCR3-dependent manner. JCI Insight 2023; 8:155006. [PMID: 36881480 DOI: 10.1172/jci.insight.155006] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Accepted: 03/01/2023] [Indexed: 03/08/2023] Open
Abstract
This study aimed to enhance anti-tumor immune responses to pancreatic cancer via antibody-based blockade of IL-6 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). Mice bearing subcutaneous or orthotopic pancreatic tumors were treated with blocking antibodies to IL 6 and/or CTLA-4. In both tumor models, dual IL-6 and CTLA-4 blockade significantly inhibited tumor growth. Additional investigations revealed that dual therapy induced an overwhelming infiltration of T cells into the tumor as well as changes in CD4+ T cell subsets. Dual blockade therapy elicited CD4+ T cells to secrete increased IFN-γ in vitro. Likewise, in vitro stimulation of pancreatic tumor cells with IFN-γ profoundly increased tumor cell production of CXCR3 specific chemokines, even in the presence of IL-6. In vivo blockade of CXCR3 prevented orthotopic tumor regression in the presence of the combination treatment, demonstrating a dependence on the CXCR3 axis for anti-tumor efficacy. Both CD4+ and CD8+ T cells were required for the anti-tumor activity of this combination therapy, as their in vivo depletion via antibodies impaired outcomes. These data represent the first report of IL-6 and CTLA 4 blockade as a means to regress pancreatic tumors with defined operative mechanisms of efficacy. Given these results, this therapeutic combination has potential for immediate clinical translation.
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Affiliation(s)
- Michael Brandon Ware
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Maggie Phillips
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Christopher McQuinn
- Department of Internal Medicine, The Ohio State University, Columbus, United States of America
| | - Mohammad Y Zaidi
- Department of Surgery, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Hannah M Knochelmann
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, United States of America
| | - Emily Greene
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Brian S Robinson
- Department of Pathology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Cameron J Herting
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Thomas A Mace
- Department of Internal Medicine, The Ohio State University, Columbus, United States of America
| | - Zhengjia Chen
- Department of Biostatistics and Bioinformatics, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Chao Zhang
- Department of Biostatistics and Bioinformatics, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Matthew R Farren
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Amanda N Ruggieri
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Jacob S Bowers
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, United States of America
| | - Reena Shakya
- Medicine, The Ohio State University, Columbus, United States of America
| | - Alton Brad Farris
- Department of Pathology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Gregory Young
- Center for Biostatistics, The Ohio State University, Columbus, United States of America
| | - William E Carson Iii
- Department of Internal Medicine, The Ohio State University, Columbus, United States of America
| | - Bassel El-Rayes
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Chrystal M Paulos
- Department of Surgery, Winship Cancer Institute of Emory University, Atlanta, United States of America
| | - Gregory B Lesinski
- Department of Hematology and Medical Oncology, Winship Cancer Institute of Emory University, Atlanta, United States of America
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3
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Saeedi BJ, Hunter-Chang S, Luo L, Li K, Liu KH, Robinson BS. Oxidative stress mediates end-organ damage in a novel model of acetaminophen-toxicity in Drosophila. Sci Rep 2022; 12:19309. [PMID: 36369211 PMCID: PMC9652370 DOI: 10.1038/s41598-022-21156-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 09/23/2022] [Indexed: 11/13/2022] Open
Abstract
Acetaminophen is the most common cause of acute drug-induced liver injury in the United States. However, research into the mechanisms of acetaminophen toxicity and the development of novel therapeutics is hampered by the lack of robust, reproducible, and cost-effective model systems. Herein, we characterize a novel Drosophila-based model of acetaminophen toxicity. We demonstrate that acetaminophen treatment of Drosophila results in similar pathophysiologic alterations as those observed in mammalian systems, including a robust production of reactive oxygen species, depletion of glutathione, and dose-dependent mortality. Moreover, these effects are concentrated in the Drosophila fat body, an organ analogous to the mammalian liver. Utilizing this system, we interrogated the influence of environmental factors on acetaminophen toxicity which has proven difficult in vertebrate models due to cost and inter-individual variability. We find that both increasing age and microbial depletion sensitize Drosophila to acetaminophen toxicity. These environmental influences both alter oxidative stress response pathways in metazoans. Indeed, genetic and pharmacologic manipulations of the antioxidant response modify acetaminophen toxicity in our model. Taken together, these data demonstrate the feasibility of Drosophila for the study of acetaminophen toxicity, bringing with it an ease of genetic and microbiome manipulation, high-throughput screening, and availability of transgenic animals.
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Affiliation(s)
- Bejan J Saeedi
- Department of Pathology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Sarah Hunter-Chang
- Department of Pathology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Liping Luo
- Department of Pathology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Kaiyan Li
- Department of Pathology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA, 30322, USA
| | - Ken H Liu
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA, 30322, USA
| | - Brian S Robinson
- Department of Pathology, Emory University School of Medicine, 615 Michael Street, Atlanta, GA, 30322, USA.
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4
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Roeder BM, Riley MR, She X, Dakos AS, Robinson BS, Moore BJ, Couture DE, Laxton AW, Popli G, Munger Clary HM, Sam M, Heck C, Nune G, Lee B, Liu C, Shaw S, Gong H, Marmarelis VZ, Berger TW, Deadwyler SA, Song D, Hampson RE. Corrigendum: Patterned hippocampal stimulation facilitates memory in patients with a history of head impact and/or brain injury. Front Hum Neurosci 2022; 16:1039221. [PMID: 36277045 PMCID: PMC9583523 DOI: 10.3389/fnhum.2022.1039221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 09/09/2022] [Indexed: 11/21/2022] Open
Affiliation(s)
- Brent M. Roeder
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Mitchell R. Riley
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Xiwei She
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Alexander S. Dakos
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Brian S. Robinson
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Bryan J. Moore
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Daniel E. Couture
- Department of Neurosurgery, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Adrian W. Laxton
- Department of Neurosurgery, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Gautam Popli
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Heidi M. Munger Clary
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Maria Sam
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Christi Heck
- Department of Neurology, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - George Nune
- Department of Neurology, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Brian Lee
- Department of Neurosurgery, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Charles Liu
- Department of Neurosurgery, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Susan Shaw
- Department of Neurology, Rancho Los Amigos National Rehabilitation Hospital, Los Angeles, CA, United States
| | - Hui Gong
- Department of Neurology, Rancho Los Amigos National Rehabilitation Hospital, Los Angeles, CA, United States
| | - Vasilis Z. Marmarelis
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Theodore W. Berger
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Sam A. Deadwyler
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Dong Song
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Robert E. Hampson
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
- *Correspondence: Robert E. Hampson
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5
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Roeder BM, Riley MR, She X, Dakos AS, Robinson BS, Moore BJ, Couture DE, Laxton AW, Popli G, Munger Clary HM, Sam M, Heck C, Nune G, Lee B, Liu C, Shaw S, Gong H, Marmarelis VZ, Berger TW, Deadwyler SA, Song D, Hampson RE. Patterned Hippocampal Stimulation Facilitates Memory in Patients With a History of Head Impact and/or Brain Injury. Front Hum Neurosci 2022; 16:933401. [PMID: 35959242 PMCID: PMC9358788 DOI: 10.3389/fnhum.2022.933401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 06/13/2022] [Indexed: 11/24/2022] Open
Abstract
Rationale: Deep brain stimulation (DBS) of the hippocampus is proposed for enhancement of memory impaired by injury or disease. Many pre-clinical DBS paradigms can be addressed in epilepsy patients undergoing intracranial monitoring for seizure localization, since they already have electrodes implanted in brain areas of interest. Even though epilepsy is usually not a memory disorder targeted by DBS, the studies can nevertheless model other memory-impacting disorders, such as Traumatic Brain Injury (TBI). Methods: Human patients undergoing Phase II invasive monitoring for intractable epilepsy were implanted with depth electrodes capable of recording neurophysiological signals. Subjects performed a delayed-match-to-sample (DMS) memory task while hippocampal ensembles from CA1 and CA3 cell layers were recorded to estimate a multi-input, multi-output (MIMO) model of CA3-to-CA1 neural encoding and a memory decoding model (MDM) to decode memory information from CA3 and CA1 neuronal signals. After model estimation, subjects again performed the DMS task while either MIMO-based or MDM-based patterned stimulation was delivered to CA1 electrode sites during the encoding phase of the DMS trials. Each subject was sorted (post hoc) by prior experience of repeated and/or mild-to-moderate brain injury (RMBI), TBI, or no history (control) and scored for percentage successful delayed recognition (DR) recall on stimulated vs. non-stimulated DMS trials. The subject’s medical history was unknown to the experimenters until after individual subject memory retention results were scored. Results: When examined compared to control subjects, both TBI and RMBI subjects showed increased memory retention in response to both MIMO and MDM-based hippocampal stimulation. Furthermore, effects of stimulation were also greater in subjects who were evaluated as having pre-existing mild-to-moderate memory impairment. Conclusion: These results show that hippocampal stimulation for memory facilitation was more beneficial for subjects who had previously suffered a brain injury (other than epilepsy), compared to control (epilepsy) subjects who had not suffered a brain injury. This study demonstrates that the epilepsy/intracranial recording model can be extended to test the ability of DBS to restore memory function in subjects who previously suffered a brain injury other than epilepsy, and support further investigation into the beneficial effect of DBS in TBI patients.
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Affiliation(s)
- Brent M. Roeder
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Mitchell R. Riley
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Xiwei She
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Alexander S. Dakos
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Brian S. Robinson
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Bryan J. Moore
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Daniel E. Couture
- Department of Neurosurgery, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Adrian W. Laxton
- Department of Neurosurgery, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Gautam Popli
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Heidi M. Munger Clary
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Maria Sam
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
| | - Christi Heck
- Department of Neurology, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - George Nune
- Department of Neurology, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Brian Lee
- Department of Neurosurgery, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Charles Liu
- Department of Neurosurgery, W. M. Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Susan Shaw
- Department of Neurology, Rancho Los Amigos National Rehabilitation Hospital, Los Angeles, CA, United States
| | - Hui Gong
- Department of Neurology, Rancho Los Amigos National Rehabilitation Hospital, Los Angeles, CA, United States
| | - Vasilis Z. Marmarelis
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Theodore W. Berger
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Sam A. Deadwyler
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
| | - Dong Song
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, United States
| | - Robert E. Hampson
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC, United States
- Department of Neurology, Wake Forest School of Medicine/Atrium Health Wake Forest Baptist, Winston-Salem, NC, United States
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6
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Robinson BS, Norman-Tenazas R, Cervantes M, Symonette D, Johnson EC, Joyce J, Rivlin PK, Hwang GM, Zhang K, Gray-Roncal W. Author Correction: Online learning for orientation estimation during translation in an insect ring attractor network. Sci Rep 2022; 12:4663. [PMID: 35304583 PMCID: PMC8933515 DOI: 10.1038/s41598-022-08814-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Brian S Robinson
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA.
| | | | - Martha Cervantes
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Danilo Symonette
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Erik C Johnson
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Justin Joyce
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Patricia K Rivlin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
| | - Grace M Hwang
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA.,Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Kechen Zhang
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, 21205, USA.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA.,Department of Neuroscience, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - William Gray-Roncal
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA.,Department of Computer Science, Johns Hopkins University, Baltimore, MD, 21218, USA
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7
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Robinson BS, Norman-Tenazas R, Cervantes M, Symonette D, Johnson EC, Joyce J, Rivlin PK, Hwang GM, Zhang K, Gray-Roncal W. Online learning for orientation estimation during translation in an insect ring attractor network. Sci Rep 2022; 12:3210. [PMID: 35217679 PMCID: PMC8881593 DOI: 10.1038/s41598-022-05798-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 01/10/2022] [Indexed: 11/09/2022] Open
Abstract
Insect neural systems are a promising source of inspiration for new navigation algorithms, especially on low size, weight, and power platforms. There have been unprecedented recent neuroscience breakthroughs with Drosophila in behavioral and neural imaging experiments as well as the mapping of detailed connectivity of neural structures. General mechanisms for learning orientation in the central complex (CX) of Drosophila have been investigated previously; however, it is unclear how these underlying mechanisms extend to cases where there is translation through an environment (beyond only rotation), which is critical for navigation in robotic systems. Here, we develop a CX neural connectivity-constrained model that performs sensor fusion, as well as unsupervised learning of visual features for path integration; we demonstrate the viability of this circuit for use in robotic systems in simulated and physical environments. Furthermore, we propose a theoretical understanding of how distributed online unsupervised network weight modification can be leveraged for learning in a trajectory through an environment by minimizing orientation estimation error. Overall, our results may enable a new class of CX-derived low power robotic navigation algorithms and lead to testable predictions to inform future neuroscience experiments.
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Affiliation(s)
- Brian S Robinson
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA.
| | | | - Martha Cervantes
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Danilo Symonette
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Erik C Johnson
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Justin Joyce
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
| | - Patricia K Rivlin
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, 20147, USA
| | - Grace M Hwang
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Kechen Zhang
- Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, 21205, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA
- Department of Neuroscience, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - William Gray-Roncal
- The Johns Hopkins University Applied Physics Laboratory, Laurel, MD, 20723, USA
- Department of Computer Science, Johns Hopkins University, Baltimore, MD, 21218, USA
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8
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Owens JA, Saeedi BJ, Naudin CR, Hunter-Chang S, Barbian ME, Eboka RU, Askew L, Darby TM, Robinson BS, Jones RM. Lactobacillus rhamnosus GG Orchestrates an Antitumor Immune Response. Cell Mol Gastroenterol Hepatol 2021; 12:1311-1327. [PMID: 34111601 PMCID: PMC8463873 DOI: 10.1016/j.jcmgh.2021.06.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS In colorectal cancer, approximately 95% of patients are refractory to immunotherapy because of low antitumor immune responses. Therefore, there is an exigent need to develop treatments that increase antitumor immune responses and decrease tumor burden to enhance immunotherapy. METHODS The gut microbiome has been described as a master modulator of immune responses. We administered the human commensal, Lactobacillus rhamnosus GG (LGG), to mice and characterized the changes in the gut immune landscape. Because the presence of lactobacilli in the gut microbiome has been linked with decreased tumor burden and antitumor immune responses, we also supplemented a genetic and a chemical model of murine intestinal cancer with LGG. For clinical relevance, we therapeutically administered LGG after tumors had formed. We also tested for the requirement of CD8 T cells in LGG-mediated modulation of gut tumor burden. RESULTS We detected increased colonic CD8 T-cell responses specifically in LGG-supplemented mice. The CD8 T-cell induction was dependent on dendritic cell activation mediated via Toll-like receptor-2, thereby describing a novel mechanism in which a member of the human microbiome induces an intestinal CD8 T-cell response. We also show that LGG decreased tumor burden in the murine gut cancer models by a CD8 T-cell-dependent manner. CONCLUSIONS These data support the potential use of LGG to augment antitumor immune responses in colorectal cancer patients and ultimately for increasing the breadth and efficacy of immunotherapy.
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Affiliation(s)
- Joshua A. Owens
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Bejan J. Saeedi
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia
| | - Crystal R. Naudin
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Sarah Hunter-Chang
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia
| | - Maria E. Barbian
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Richard U. Eboka
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia
| | - Lauren Askew
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Trevor M. Darby
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Brian S. Robinson
- Department of Pathology, Emory University School of Medicine, Atlanta, Georgia
| | - Rheinallt M. Jones
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia,Emory Microbiome Research Center, Emory University School of Medicine, Atlanta, Georgia,Correspondence Address correspondence to: Rheinallt M. Jones, PhD, Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, 615 Michael Street, Atlanta, Georgia 30322. fax: (404) 727-8538.
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9
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Naudin CR, Maner-Smith K, Owens JA, Wynn GM, Robinson BS, Matthews JD, Reedy AR, Luo L, Wolfarth AA, Darby TM, Ortlund EA, Jones RM. Lactococcus lactis Subspecies cremoris Elicits Protection Against Metabolic Changes Induced by a Western-Style Diet. Gastroenterology 2020; 159:639-651.e5. [PMID: 32169430 DOI: 10.1053/j.gastro.2020.03.010] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS A Western-style diet, which is high in fat and sugar, can cause significant dyslipidemia and nonalcoholic fatty liver disease; the diet has an especially strong effect in women, regardless of total calorie intake. Dietary supplementation with beneficial microbes might reduce the detrimental effects of a Western-style diet. We assessed the effects of Lactococcus lactis subspecies (subsp) cremoris on weight gain, liver fat, serum cholesterol, and insulin resistance in female mice on a high-fat, high-carbohydrate diet. METHODS Female C57BL/6 mice were fed either a high-fat, high-carbohydrate (Western-style) diet that contained 40% fat (mostly milk fat) and 43% carbohydrate (mostly sucrose) or a calorie-matched-per-gram control diet. The diets of mice were supplemented with 1 × 109 colony-forming units of L lactis subsp cremoris ATCC 19257 or Lactobacillus rhamnosus GG ATCC 53103 (control bacteria) 3 times per week for 16 weeks. Body weights were measured, and fecal, blood, and liver tissues were collected and analyzed. Livers were analyzed for fat accumulation and inflammation, and blood samples were analyzed for cholesterol and glucose levels. Mice were housed within Comprehensive Lab Animal Monitoring System cages, and respiratory exchange ratio and activity were measured. Hepatic lipid profiles of L lactis subsp cremoris-supplemented mice were characterized by lipidomics mass spectrometry analysis. RESULTS Mice fed L lactis subsp cremoris while on the Western-style diet gained less weight, developed less hepatic steatosis and inflammation, and had a lower mean serum level of cholesterol and body mass index than mice fed the control bacteria. Mice fed the L lactis subsp cremoris had increased glucose tolerance while on the Western-style diet compared to mice fed control bacteria and had alterations in hepatic lipids, including oxylipins. CONCLUSIONS Dietary supplementation with L lactis subsp cremoris in female mice on a high-fat, high-carbohydrate (Western-style) diet caused them to gain less weight, develop less liver fat and inflammation, reduce serum cholesterol levels, and increase glucose tolerance compared with mice on the same diet fed control bacteria. L lactis subsp cremoris is safe for oral ingestion and might be developed for persons with metabolic and liver disorders caused by a Western-style diet.
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Affiliation(s)
- Crystal R Naudin
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Kristal Maner-Smith
- Emory Integrated Metabolomics and Lipidomics Core, Emory University, Atlanta, Georgia
| | - Joshua A Owens
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Grace M Wynn
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Jason D Matthews
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - April R Reedy
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Liping Luo
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Alexandra A Wolfarth
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - Trevor M Darby
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia
| | - Eric A Ortlund
- Department of Biochemistry, Emory University, Atlanta, Georgia, United States of America
| | - Rheinallt M Jones
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University, Atlanta, Georgia.
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10
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Wolfarth AA, Liu X, Darby TM, Boyer DJ, Spizman JB, Owens JA, Chandrasekharan B, Naudin CR, Hanley KZ, Robinson BS, Ortlund EA, Jones RM, Neish AS. Proline-Rich Acidic Protein 1 (PRAP1) Protects the Gastrointestinal Epithelium From Irradiation-Induced Apoptosis. Cell Mol Gastroenterol Hepatol 2020; 10:713-727. [PMID: 32629119 PMCID: PMC7498829 DOI: 10.1016/j.jcmgh.2020.06.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 12/22/2022]
Abstract
BACKGROUND & AIMS The intestinal epithelium must be resilient to physiochemical stress to uphold the physiological barrier separating the systemic compartment from the microbial and antigenic components of the gut lumen. Identifying proteins that mediate protection and enhancing their expression is therefore a clear approach to promote intestinal health. We previously reported that oral ingestion of the probiotic Lactobacillus rhamnosus GG not only induced the expression of several recognized cytoprotective factors in the murine colon, but also many genes with no previously described function, including the gene encoding proline-rich acidic protein 1 (PRAP1). PRAP1 is a highly expressed protein in the epithelium of the gastrointestinal tract and we sought to define its function in this tissue. METHODS Purified preparations of recombinant PRAP1 were analyzed biochemically and PRAP1 antisera were used to visualize localization in tissues. Prap1-/- mice were characterized at baseline and challenged with total body irradiation, then enteroids were generated to recapitulate the irradiation challenge ex vivo. RESULTS PRAP1 is a 17-kilodalton intrinsically disordered protein with no recognizable sequence homology. PRAP1 expression levels were high in the epithelia of the small intestine. Although Prap1-/- mice presented only mild phenotypes at baseline, they were highly susceptible to intestinal injury upon challenge. After irradiation, the Prap1-/- mice showed accelerated death with a significant increase in apoptosis and p21 expression in the small intestinal epithelium. CONCLUSIONS PRAP1 is an intrinsically disordered protein highly expressed by the gastrointestinal epithelium and functions at exposed surfaces to protect the barrier from oxidative insult.
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Affiliation(s)
- Alexandra A Wolfarth
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Xu Liu
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia
| | - Trevor M Darby
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Darra J Boyer
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Jocelyn B Spizman
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Joshua A Owens
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Bindu Chandrasekharan
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Crystal R Naudin
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Krisztina Z Hanley
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, Georgia
| | - Rheinallt M Jones
- Division of Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia; Emory Microbiome Research Center, Emory University School of Medicine, Atlanta, Georgia
| | - Andrew S Neish
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia; Emory Microbiome Research Center, Emory University School of Medicine, Atlanta, Georgia.
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11
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She X, Robinson BS, Berger TW, Song D. Accelerating Estimation of a Multi-Input Multi-Output Model of the Hippocampus with a Parallel Computing Strategy. Annu Int Conf IEEE Eng Med Biol Soc 2020; 2020:2479-2482. [PMID: 33018509 DOI: 10.1109/embc44109.2020.9175490] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To build hippocampal memory prosthesis for restoring memory functions, we previously developed and implemented a multi-input multi-output (MIMO) nonlinear dynamic model of the hippocampus. This model can successfully predict hippocampal output spike activities based on input spike activities, and thus be used to drive microstimulation to bypass the damaged hippocampal region. Building such a MIMO model involves estimations of a large number of model coefficients, which typically takes hundreds of hours using a single personal computer. In practice, however, due to the requirement of medical care and clinical trials, the modeling processes must be completed within 72 hours after the recording, so that models can be used to drive stimulations. To solve this problem, we utilized a parallelization strategy to divide the whole MIMO model computation involving iterative estimation and optimization into independent computing tasks that can be performed simultaneously in multiple computer nodes. Such a strategy was implemented on the high-performance computing cluster at the University of Southern California. It reduced the model estimation time to tens of hours and thus allowed us to complete the modeling process within the required time frame to further test model-driven electrical stimulation for the hippocampal memory prosthesis.
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12
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Saeedi BJ, Liu KH, Owens JA, Hunter-Chang S, Camacho MC, Eboka RU, Chandrasekharan B, Baker NF, Darby TM, Robinson BS, Jones RM, Jones DP, Neish AS. Gut-Resident Lactobacilli Activate Hepatic Nrf2 and Protect Against Oxidative Liver Injury. Cell Metab 2020; 31:956-968.e5. [PMID: 32213347 PMCID: PMC7329068 DOI: 10.1016/j.cmet.2020.03.006] [Citation(s) in RCA: 139] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 01/09/2020] [Accepted: 03/03/2020] [Indexed: 02/07/2023]
Abstract
Many studies have suggested a role for gut-resident microbes (the "gut microbiome") in modulating host health; however, the mechanisms by which they impact systemic physiology remain largely unknown. In this study, metabolomic and transcriptional profiling of germ-free and conventionalized mouse liver revealed an upregulation of the Nrf2 antioxidant and xenobiotic response in microbiome-replete animals. Using a Drosophila-based screening assay, we identified members of the genus Lactobacillus capable of stimulating Nrf2. Indeed, the human commensal Lactobacillus rhamnosus GG (LGG) potently activated Nrf2 in the Drosophila liver analog and the murine liver. This activation was sufficient to protect against two models of oxidative liver injury, acetaminophen overdose and acute ethanol toxicity. Characterization of the portal circulation of LGG-treated mice by tandem mass spectrometry identified a small molecule activator of Nrf2, 5-methoxyindoleacetic acid, produced by LGG. Taken together, these data demonstrate a mechanism by which intestinal microbes modulate hepatic susceptibility to oxidative injury.
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Affiliation(s)
- Bejan J Saeedi
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Ken H Liu
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Joshua A Owens
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Sarah Hunter-Chang
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Mary C Camacho
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Richard U Eboka
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Bindu Chandrasekharan
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nusaiba F Baker
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Trevor M Darby
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Brian S Robinson
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Rheinallt M Jones
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Dean P Jones
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Andrew S Neish
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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13
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Robinson BS, Saeedi B, Arthur CM, Owens J, Naudin C, Ahmed N, Luo L, Jones R, Neish A, Stowell SR. Galectin-9 Is a Novel Regulator of Epithelial Restitution. Am J Pathol 2020; 190:1657-1666. [PMID: 32380082 DOI: 10.1016/j.ajpath.2020.04.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 03/23/2020] [Accepted: 04/08/2020] [Indexed: 12/19/2022]
Abstract
Increasingly, the ß-galactoside binding lectins, termed galectins, are being recognized as critical regulators of cell function and organismal homeostasis. Within the context of the mucosal surface, galectins are established regulators of innate and adaptive immune responses, microbial populations, and several critical epithelial functions, including cell migration, proliferation, and response to injury. However, given their complex tissue distribution and expression patterns, their role within specific processes remains poorly understood. We took a genetic approach to understand the role of endogenous galectin-9 (Gal-9), a mucosal galectin that has been linked to inflammatory bowel disease, within the context of the murine intestine. Gal-9-deficient (Gal9-/-, also known as Lgals9-/-) animals show increased sensitivity to chemically induced colitis and impaired proliferation in the setting of acute injury. Moreover, Gal9-/--derived enteroids showed impaired growth ex vivo. Consistent with a model in which endogenous Gal-9 controls epithelial growth and repair, Gal9-/- animals showed increased sensitivity to intestinal challenge in multiple models of epithelial injury, including acute irradiation injury and ectopic wound biopsies. Finally, regenerating crypts from patient biopsies showed increased expression of Gal-9, indicating these processes may be conserved in humans. Taken together, these studies implicate Gal-9 in the regulation of cellular proliferation and epithelial restitution after intestinal epithelial injury.
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Affiliation(s)
- Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Bejan Saeedi
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Connie M Arthur
- Center for Transfusion and Cellular Therapies, Emory University School of Medicine, Atlanta, Georgia
| | - Josh Owens
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Crystal Naudin
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Nourine Ahmed
- Center for Transfusion and Cellular Therapies, Emory University School of Medicine, Atlanta, Georgia
| | - Liping Luo
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Rheinallt Jones
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Andrew Neish
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia.
| | - Sean R Stowell
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia; Center for Transfusion and Cellular Therapies, Emory University School of Medicine, Atlanta, Georgia.
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14
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Robinson BS, Arthur CM, Evavold B, Roback E, Kamili NA, Stowell CS, Vallecillo-Zúniga ML, Van Ry PM, Dias-Baruffi M, Cummings RD, Stowell SR. The Sweet-Side of Leukocytes: Galectins as Master Regulators of Neutrophil Function. Front Immunol 2019; 10:1762. [PMID: 31440233 PMCID: PMC6693361 DOI: 10.3389/fimmu.2019.01762] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 07/11/2019] [Indexed: 12/13/2022] Open
Abstract
Among responders to microbial invasion, neutrophils represent one of the earliest and perhaps most important factors that contribute to initial host defense. Effective neutrophil immunity requires their rapid mobilization to the site of infection, which requires efficient extravasation, activation, chemotaxis, phagocytosis, and eventual killing of potential microbial pathogens. Following pathogen elimination, neutrophils must be eliminated to prevent additional host injury and subsequent exacerbation of the inflammatory response. Galectins, expressed in nearly every tissue and regulated by unique sensitivity to oxidative and proteolytic inactivation, appear to influence nearly every aspect of neutrophil function. In this review, we will examine the impact of galectins on neutrophils, with a particular focus on the unique biochemical traits that allow galectin family members to spatially and temporally regulate neutrophil function.
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Affiliation(s)
- Brian S Robinson
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | - Connie M Arthur
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | - Birk Evavold
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | - Ethan Roback
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | - Nourine A Kamili
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | - Caleb S Stowell
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
| | | | - Pam M Van Ry
- Department of Biochemistry, Brigham Young University, Provo, UT, United States
| | - Marcelo Dias-Baruffi
- Department of Clinical Analyses, Toxicology and Food Sciences, School of Pharmaceutical Sciences of Ribeirao Preto, University of São Paulo, São Paulo, Brazil
| | - Richard D Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Sean R Stowell
- Department of Laboratory Medicine and Pathology, Center for Transfusion Medicine and Cellular Therapies, Emory University School of Medicine, Atlanta, GA, United States
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15
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Saeedi BJ, Robinson BS, Owens J, Liu K, Eboka R, Darby T, Luo L, Jones D, Jones R, Neish A. Regulation of the Hepatic Antioxidant Response by the Probiotic
Lactobacillus rhamnosus
GG. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.369.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | - Ken Liu
- PharmacologyEmory UniversityAtlantaGA
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16
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Arthur CM, Nalbant D, Feldman HA, Saeedi BJ, Matthews J, Robinson BS, Kamili NA, Bennett A, Cress GA, Sola-Visner M, Jones RM, Zimmerman MB, Neish AS, Patel RM, Nopoulos P, Georgieff MK, Roback JD, Widness JA, Josephson CD, Stowell SR. Anemia induces gut inflammation and injury in an animal model of preterm infants. Transfusion 2019; 59:1233-1245. [PMID: 30897226 DOI: 10.1111/trf.15254] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 11/12/2018] [Accepted: 11/28/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND While very low birth weight (VLBW) infants often require multiple red blood cell transfusions, efforts to minimize transfusion-associated risks have resulted in more restrictive neonatal transfusion practices. However, whether restrictive transfusion strategies limit transfusions without increasing morbidity and mortality in this population remains unclear. Recent epidemiologic studies suggest that severe anemia may be an important risk factor for the development of necrotizing enterocolitis (NEC). However, the mechanism whereby anemia may lead to NEC remains unknown. STUDY DESIGN AND METHODS The potential impact of anemia on neonatal inflammation and intestinal barrier disruption, two well-characterized predisposing features of NEC, was defined by correlation of hemoglobin values to cytokine levels in premature infants and by direct evaluation of intestinal hypoxia, inflammation and gut barrier disruption using a pre-clinical neonatal murine model of phlebotomy-induced anemia (PIA). RESULTS Increasing severity of anemia in the preterm infant correlated with the level of IFN-gamma, a key pro-inflammatory cytokine that may predispose an infant to NEC. Gradual induction of PIA in a pre-clinical model resulted in significant hypoxia throughout the intestinal mucosa, including areas where intestinal macrophages reside. PIA-induced hypoxia significantly increased macrophage pro-inflammatory cytokine levels, while reducing tight junction protein ZO-1 expression and increasing intestinal barrier permeability. Macrophage depletion reversed the impact of anemia on intestinal ZO-1 expression and barrier function. CONCLUSIONS Taken together, these results suggest that anemia can increase intestinal inflammation and barrier disruption likely through altered macrophage function, leading to the type of predisposing intestinal injury that may increase the risk for NEC.
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Affiliation(s)
- Connie M Arthur
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Demet Nalbant
- Department of Pediatrics, University of Iowa, Iowa City, Iowa
| | - Henry A Feldman
- Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts
| | - Bejan J Saeedi
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Jason Matthews
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Brian S Robinson
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Nourine A Kamili
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Ashley Bennett
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | | | - Martha Sola-Visner
- Division of Newborn Medicine, Boston Children's Hospital, Boston, Massachusetts
| | - Rheinallt M Jones
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | | | - Andrew S Neish
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - Ravi M Patel
- Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Peggy Nopoulos
- Department of Psychiatry, College of Medicine, University of Iowa, Iowa City, Iowa
| | - Michael K Georgieff
- Department of Pediatrics, School of Medicine, University of Minnesota, Minneapolis, Minnesota
| | - John D Roback
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
| | - John A Widness
- Department of Pediatrics, University of Iowa, Iowa City, Iowa
| | - Cassandra D Josephson
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia.,Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - Sean R Stowell
- Departments of Pathology and Laboratory Medicine, Center for Transfusion and Cellular Therapies, Atlanta, Georgia
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17
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Darby TM, Owens JA, Saeedi BJ, Luo L, Matthews JD, Robinson BS, Naudin CR, Jones RM. Lactococcus Lactis Subsp. cremoris Is an Efficacious Beneficial Bacterium that Limits Tissue Injury in the Intestine. iScience 2019; 12:356-367. [PMID: 30739017 PMCID: PMC6369221 DOI: 10.1016/j.isci.2019.01.030] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 12/21/2018] [Accepted: 01/24/2019] [Indexed: 02/06/2023] Open
Abstract
The use of beneficial bacteria to promote health is widely practiced. However, experimental evidence corroborating the efficacy of bacteria promoted with such claims remains limited. We address this gap by identifying a beneficial bacterium that protects against tissue damage and injury-induced inflammation in the gut. We first employed the Drosophila animal model to screen for the capacity of candidate beneficial bacteria to protect the fly gut against injury. From this screen, we identified Lactococcus lactis subsp. cremoris as a bacterium that elicited potent cytoprotective activity. Then, in a murine model, we demonstrated that the same strain confers powerful cytoprotective influences against radiological damage, as well as anti-inflammatory activity in a gut colitis model. In summary, we demonstrate the positive salutary effects of a beneficial bacterium, namely, L. lactis subsp. cremoris on intestinal tissue and propose the use of this strain as a therapeutic to promote intestinal health. Drosophila can be used as an animal model to screen for beneficial bacteria Lactococcus lactis subsp. cremoris elicited potent cytoprotection in the fly gut L. lactis cremoris elicited anti-inflammatory activity in a mouse colitis model L. lactis cremoris activated the cytoprotective Nrf2 pathway in flies and mice
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Affiliation(s)
- Trevor M Darby
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, 615 Michael Street, Atlanta GA 30322, USA
| | - Joshua A Owens
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, 615 Michael Street, Atlanta GA 30322, USA
| | - Bejan J Saeedi
- Department of Pathology, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Liping Luo
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, 615 Michael Street, Atlanta GA 30322, USA
| | - Jason D Matthews
- Department of Pathology, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Brian S Robinson
- Department of Pathology, Emory University School of Medicine, Atlanta GA 30322, USA
| | - Crystal R Naudin
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, 615 Michael Street, Atlanta GA 30322, USA
| | - Rheinallt M Jones
- Division of Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, 615 Michael Street, Atlanta GA 30322, USA.
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18
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Affiliation(s)
- Brian S. Robinson
- Center for Transfusion Medicine and Cellular Therapies, Department of Laboratory Medicine and Pathology, Emory University School of Medicine
| | - Connie M. Arthur
- Center for Transfusion Medicine and Cellular Therapies, Department of Laboratory Medicine and Pathology, Emory University School of Medicine
| | - Nourine A. Kamili
- Center for Transfusion Medicine and Cellular Therapies, Department of Laboratory Medicine and Pathology, Emory University School of Medicine
| | - Sean R. Stowell
- Center for Transfusion Medicine and Cellular Therapies, Department of Laboratory Medicine and Pathology, Emory University School of Medicine
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19
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Hampson RE, Song D, Robinson BS, Fetterhoff D, Dakos AS, Roeder BM, She X, Wicks RT, Witcher MR, Couture DE, Laxton AW, Munger-Clary H, Popli G, Sollman MJ, Whitlow CT, Marmarelis VZ, Berger TW, Deadwyler SA. Developing a hippocampal neural prosthetic to facilitate human memory encoding and recall. J Neural Eng 2018; 15:036014. [PMID: 29589592 DOI: 10.1088/1741-2552/aaaed7] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE We demonstrate here the first successful implementation in humans of a proof-of-concept system for restoring and improving memory function via facilitation of memory encoding using the patient's own hippocampal spatiotemporal neural codes for memory. Memory in humans is subject to disruption by drugs, disease and brain injury, yet previous attempts to restore or rescue memory function in humans typically involved only nonspecific, modulation of brain areas and neural systems related to memory retrieval. APPROACH We have constructed a model of processes by which the hippocampus encodes memory items via spatiotemporal firing of neural ensembles that underlie the successful encoding of short-term memory. A nonlinear multi-input, multi-output (MIMO) model of hippocampal CA3 and CA1 neural firing is computed that predicts activation patterns of CA1 neurons during the encoding (sample) phase of a delayed match-to-sample (DMS) human short-term memory task. MAIN RESULTS MIMO model-derived electrical stimulation delivered to the same CA1 locations during the sample phase of DMS trials facilitated short-term/working memory by 37% during the task. Longer term memory retention was also tested in the same human subjects with a delayed recognition (DR) task that utilized images from the DMS task, along with images that were not from the task. Across the subjects, the stimulated trials exhibited significant improvement (35%) in both short-term and long-term retention of visual information. SIGNIFICANCE These results demonstrate the facilitation of memory encoding which is an important feature for the construction of an implantable neural prosthetic to improve human memory.
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Affiliation(s)
- Robert E Hampson
- Wake Forest Baptist Medical Center, Winston-Salem, NC, United States of America
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Ferrebee CB, Li J, Haywood J, Pachura K, Robinson BS, Hinrichs BH, Jones RM, Rao A, Dawson PA. Organic Solute Transporter α-β Protects Ileal Enterocytes From Bile Acid-Induced Injury. Cell Mol Gastroenterol Hepatol 2018; 5:499-522. [PMID: 29930976 PMCID: PMC6009794 DOI: 10.1016/j.jcmgh.2018.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 01/05/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND & AIMS Ileal bile acid absorption is mediated by uptake via the apical sodium-dependent bile acid transporter (ASBT), and export via the basolateral heteromeric organic solute transporter α-β (OSTα-OSTβ). In this study, we investigated the cytotoxic effects of enterocyte bile acid stasis in Ostα-/- mice, including the temporal relationship between intestinal injury and initiation of the enterohepatic circulation of bile acids. METHODS Ileal tissue morphometry, histology, markers of cell proliferation, gene, and protein expression were analyzed in male and female wild-type and Ostα-/- mice at postnatal days 5, 10, 15, 20, and 30. Ostα-/-Asbt-/- mice were generated and analyzed. Bile acid activation of intestinal Nrf2-activated pathways was investigated in Drosophila. RESULTS As early as day 5, Ostα-/- mice showed significantly increased ileal weight per length, decreased villus height, and increased epithelial cell proliferation. This correlated with premature expression of the Asbt and induction of bile acid-activated farnesoid X receptor target genes in neonatal Ostα-/- mice. Expression of reduced nicotinamide adenine dinucleotide phosphate oxidase-1 and Nrf2-anti-oxidant responsive genes were increased significantly in neonatal Ostα-/- mice at these postnatal time points. Bile acids also activated Nrf2 in Drosophila enterocytes and enterocyte-specific knockdown of Nrf2 increased sensitivity of flies to bile acid-induced toxicity. Inactivation of the Asbt prevented the changes in ileal morphology and induction of anti-oxidant response genes in Ostα-/- mice. CONCLUSIONS Early in postnatal development, loss of Ostα leads to bile acid accumulation, oxidative stress, and a restitution response in ileum. In addition to its essential role in maintaining bile acid homeostasis, Ostα-Ostβ functions to protect the ileal epithelium against bile acid-induced injury. NCBI Gene Expression Omnibus: GSE99579.
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Key Words
- ARE, anti-oxidant response element
- Asbt, apical sodium-dependent bile acid transporter
- CDCA, chenodeoxycholic acid
- Drosophila
- FGF, fibroblast growth factor
- FXR, farnesoid X receptor
- GAPDH, glyceraldehyde-3-phosphate dehydrogenase
- GFP, green fluorescence protein
- GSH, reduced glutathione
- GSSG, oxidized glutathione
- Ibabp, ileal bile acid binding protein
- Ileum
- NEC, necrotizing enterocolitis
- Neonate
- Nox, reduced nicotinamide adenine dinucleotide phosphate oxidase
- Nrf2, nuclear factor (erythroid-derived 2)-like 2
- Nuclear Factor Erythroid-Derived 2-Like 2
- Ost, organic solute transporter
- PBS, phosphate-buffered saline
- ROS, reactive oxygen species
- Reactive Oxygen Species
- TNF, tumor necrosis factor
- TUNEL, terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling
- WT, wild type
- cRNA, complementary RNA
- mRNA, messenger RNA
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Affiliation(s)
- Courtney B. Ferrebee
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Jianing Li
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
| | - Jamie Haywood
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Kimberly Pachura
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
| | | | | | - Rheinallt M. Jones
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
| | - Anuradha Rao
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
| | - Paul A. Dawson
- Department of Pediatrics, Division of Gastroenterology, Hepatology, and Nutrition, Emory University, Atlanta, Georgia
- Children’s Healthcare of Atlanta, Atlanta, Georgia
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Gilbert-Ross M, Konen J, Koo J, Shupe J, Robinson BS, Wiles WG, Huang C, Martin WD, Behera M, Smith GH, Hill CE, Rossi MR, Sica GL, Rupji M, Chen Z, Kowalski J, Kasinski AL, Ramalingam SS, Fu H, Khuri FR, Zhou W, Marcus AI. Targeting adhesion signaling in KRAS, LKB1 mutant lung adenocarcinoma. JCI Insight 2017; 2:e90487. [PMID: 28289710 PMCID: PMC5333956 DOI: 10.1172/jci.insight.90487] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Loss of LKB1 activity is prevalent in KRAS mutant lung adenocarcinoma and promotes aggressive and treatment-resistant tumors. Previous studies have shown that LKB1 is a negative regulator of the focal adhesion kinase (FAK), but in vivo studies testing the efficacy of FAK inhibition in LKB1 mutant cancers are lacking. Here, we took a pharmacologic approach to show that FAK inhibition is an effective early-treatment strategy for this high-risk molecular subtype. We established a lenti-Cre-induced Kras and Lkb1 mutant genetically engineered mouse model (KLLenti) that develops 100% lung adenocarcinoma and showed that high spatiotemporal FAK activation occurs in collective invasive cells that are surrounded by high levels of collagen. Modeling invasion in 3D, loss of Lkb1, but not p53, was sufficient to drive collective invasion and collagen alignment that was highly sensitive to FAK inhibition. Treatment of early, stage-matched KLLenti tumors with FAK inhibitor monotherapy resulted in a striking effect on tumor progression, invasion, and tumor-associated collagen. Chronic treatment extended survival and impeded local lymph node spread. Lastly, we identified focally upregulated FAK and collagen-associated collective invasion in KRAS and LKB1 comutated human lung adenocarcinoma patients. Our results suggest that patients with LKB1 mutant tumors should be stratified for early treatment with FAK inhibitors.
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Affiliation(s)
- Melissa Gilbert-Ross
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - Jessica Konen
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - Junghui Koo
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - John Shupe
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine
| | - Walter Guy Wiles
- Winship Cancer Institute of Emory University.,The Cancer Animal Models Shared Resource
| | - Chunzi Huang
- Winship Cancer Institute of Emory University.,The Cancer Animal Models Shared Resource
| | - W David Martin
- Department of Hematology and Medical Oncology, Emory University School of Medicine
| | - Madhusmita Behera
- Winship Research Informatics Shared Resource, Winship Cancer Institute
| | - Geoffrey H Smith
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine
| | - Charles E Hill
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine
| | - Michael R Rossi
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine.,Department of Radiation Oncology, Emory University School of Medicine
| | - Gabriel L Sica
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine
| | | | - Zhengjia Chen
- Winship Cancer Institute of Emory University.,Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Jeanne Kowalski
- Winship Cancer Institute of Emory University.,Department of Biostatistics and Bioinformatics, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA
| | - Andrea L Kasinski
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Suresh S Ramalingam
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - Haian Fu
- Winship Cancer Institute of Emory University.,Department of Pharmacology, Emory University School of Medicine
| | - Fadlo R Khuri
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
| | - Wei Zhou
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University.,Department of Pathology and Laboratory Medicine, Emory University School of Medicine.,Department of Human Genetics, Emory University, Atlanta, Georgia, USA
| | - Adam I Marcus
- Department of Hematology and Medical Oncology, Emory University School of Medicine.,Winship Cancer Institute of Emory University
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Hampson RE, Robinson BS, Marmarelis VZ, Deadwyler SA, Berger TW. Decoding memory features from hippocampal spiking activities using sparse classification models. Annu Int Conf IEEE Eng Med Biol Soc 2017; 2016:1620-1623. [PMID: 28268639 DOI: 10.1109/embc.2016.7591023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To understand how memory information is encoded in the hippocampus, we build classification models to decode memory features from hippocampal CA3 and CA1 spatio-temporal patterns of spikes recorded from epilepsy patients performing a memory-dependent delayed match-to-sample task. The classification model consists of a set of B-spline basis functions for extracting memory features from the spike patterns, and a sparse logistic regression classifier for generating binary categorical output of memory features. Results show that classification models can extract significant amount of memory information with respects to types of memory tasks and categories of sample images used in the task, despite the high level of variability in prediction accuracy due to the small sample size. These results support the hypothesis that memories are encoded in the hippocampal activities and have important implication to the development of hippocampal memory prostheses.
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Robinson BS, Berger TW. Monte Carlo validation of spike-timing-dependent plasticity identification from spiking activity. Annu Int Conf IEEE Eng Med Biol Soc 2017; 2016:1624-1627. [PMID: 28268640 DOI: 10.1109/embc.2016.7591024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
As increasingly complex non-stationary models become possible to be identified from neural data, rigorous validation approaches must be developed to rule out overfitting and the potential to identify features by chance. Specifically, identification of spike-timing-dependent plasticity (STDP) from recorded spontaneous in vivo spike timing is a potentially powerful tool to quantify activity-dependent plasticity. In previous work, we presented a methodology to perform this STDP identification from spike timing alone and successfully identified a generative model. Validation was straightforward with the generative model because the underlying model was known, but becomes challenging when applied to experimental data. Here, we introduce a set of null hypothesis tests that can be performed with Monte Carlo (MC) simulations of null models to rule out cases of overfitting with experimental data. We demonstrate the identification of these null models and null hypothesis testing on a generative model in two test cases, one with and one without overfitting. Importantly, we show that it is possible to distinguish an identified STDP rule from a null case where there are similar weight fluctuations which are activity-independent. With the development of the null hypothesis tests described here, STDP identification can be effectively applied to experimental data recordings.
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Nanes BA, Grimsley-Myers CM, Cadwell CM, Robinson BS, Lowery AM, Vincent PA, Mosunjac M, Früh K, Kowalczyk AP. p120-catenin regulates VE-cadherin endocytosis and degradation induced by the Kaposi sarcoma-associated ubiquitin ligase K5. Mol Biol Cell 2016; 28:30-40. [PMID: 27798235 PMCID: PMC5221628 DOI: 10.1091/mbc.e16-06-0459] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/20/2016] [Accepted: 10/19/2016] [Indexed: 12/30/2022] Open
Abstract
Endocytosis of VE-cadherin in response to the Kaposi sarcoma E3 ubiquitin ligase K5 is dependent on two membrane-proximal lysine residues but independent of a constitutive endocytosis motif. p120-catenin blocks endocytosis mediated by both motifs, demonstrating that p120 is a master regulator of multiple context-dependent endocytic signals. Vascular endothelial (VE)-cadherin undergoes constitutive internalization driven by a unique endocytic motif that also serves as a p120-catenin (p120) binding site. p120 binding masks the motif, stabilizing the cadherin at cell junctions. This mechanism allows constitutive VE-cadherin endocytosis and recycling to contribute to adherens junction dynamics without resulting in junction disassembly. Here we identify an additional motif that drives VE-cadherin endocytosis and pathological junction disassembly associated with the endothelial-derived tumor Kaposi sarcoma. Human herpesvirus 8, which causes Kaposi sarcoma, expresses the MARCH family ubiquitin ligase K5. We report that K5 targets two membrane-proximal VE-cadherin lysine residues for ubiquitination, driving endocytosis and down-regulation of the cadherin. K5-induced VE-cadherin endocytosis does not require the constitutive endocytic motif. However, K5-induced VE-cadherin endocytosis is associated with displacement of p120 from the cadherin, and p120 protects VE-cadherin from K5. Thus multiple context-dependent signals drive VE-cadherin endocytosis, but p120 binding to the cadherin juxtamembrane domain acts as a master regulator guarding cadherin stability.
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Affiliation(s)
- Benjamin A Nanes
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University School of Medicine, Atlanta, GA 30322.,Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | | | - Chantel M Cadwell
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University School of Medicine, Atlanta, GA 30322.,Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | - Brian S Robinson
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Anthony M Lowery
- Center for Cardiovascular Sciences, Albany Medical College, Albany, NY 12208
| | - Peter A Vincent
- Center for Cardiovascular Sciences, Albany Medical College, Albany, NY 12208
| | - Marina Mosunjac
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322
| | - Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR 97006
| | - Andrew P Kowalczyk
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322 .,Department of Dermatology, and, Emory University School of Medicine, Atlanta, GA 30322.,Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322
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25
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Nanes BA, Robinson BS, Mosunjac M, Fruh K, Kowalczyk AP. An alternate endocytic motif mediates VE-cadherin degradation by Kaposi sarcoma-associated herpesvirus. J Dermatol Sci 2016. [DOI: 10.1016/j.jdermsci.2016.08.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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26
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Song D, Robinson BS, Hampson RE, Marmarelis VZ, Deadwyler SA, Berger TW. Sparse Large-Scale Nonlinear Dynamical Modeling of Human Hippocampus for Memory Prostheses. IEEE Trans Neural Syst Rehabil Eng 2016; 26:272-280. [PMID: 28113595 DOI: 10.1109/tnsre.2016.2604423] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In order to build hippocampal prostheses for restoring memory functions, we build sparse multi-input, multi-output (MIMO) nonlinear dynamical models of the human hippocampus. Spike trains are recorded from hippocampal CA3 and CA1 regions of epileptic patients performing a variety of memory-dependent delayed match-to-sample (DMS) tasks. Using CA3 and CA1 spike trains as inputs and outputs respectively, sparse generalized Laguerre-Volterra models are estimated with group lasso and local coordinate descent methods to capture the nonlinear dynamics underlying the CA3-CA1 spike train transformations. These models can accurately predict the CA1 spike trains based on the ongoing CA3 spike trains during multiple memory events, e.g., sample presentation, sample response, match presentation and match response, of the DMS task, and thus will serve as the computational basis of human hippocampal memory prostheses.
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Robinson BS, Berger TW, Song D. Identification of Stable Spike-Timing-Dependent Plasticity from Spiking Activity with Generalized Multilinear Modeling. Neural Comput 2016; 28:2320-2351. [PMID: 27557101 DOI: 10.1162/neco_a_00883] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Characterization of long-term activity-dependent plasticity from behaviorally driven spiking activity is important for understanding the underlying mechanisms of learning and memory. In this letter, we present a computational framework for quantifying spike-timing-dependent plasticity (STDP) during behavior by identifying a functional plasticity rule solely from spiking activity. First, we formulate a flexible point-process spiking neuron model structure with STDP, which includes functions that characterize the stationary and plastic properties of the neuron. The STDP model includes a novel function for prolonged plasticity induction, as well as a more typical function for synaptic weight change based on the relative timing of input-output spike pairs. Consideration for system stability is incorporated with weight-dependent synaptic modification. Next, we formalize an estimation technique using a generalized multilinear model (GMLM) structure with basis function expansion. The weight-dependent synaptic modification adds a nonlinearity to the model, which is addressed with an iterative unconstrained optimization approach. Finally, we demonstrate successful model estimation on simulated spiking data and show that all model functions can be estimated accurately with this method across a variety of simulation parameters, such as number of inputs, output firing rate, input firing type, and simulation time. Since this approach requires only naturally generated spikes, it can be readily applied to behaving animal studies to characterize the underlying mechanisms of learning and memory.
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Affiliation(s)
- Brian S Robinson
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, U.S.A.
| | - Theodore W Berger
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, U.S.A.
| | - Dong Song
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, U.S.A.
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28
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Gilbert-Ross M, Konen J, Koo J, Shupe J, Sica GL, Chen Z, Robinson BS, Behera M, Rossi MR, Smith GH, Hill CE, Ramalingam SM, Fu H, Khuri FR, Zhou W, Marcus A. Abstract LB-348: Developing a personalized anti-metastatic therapy to treat KRAS, LKB1-mutant lung adenocarcinoma. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-lb-348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
LKB1 is the 2rd most commonly mutated tumor suppressor gene in human lung adenocarcinoma, is commonly co-mutated with KRAS, and leads to more aggressive, treatment-resistant tumors in mouse models. The identification of druggable signaling molecules that result from specific alterations in LKB1 could result in a personalized clinical strategy to target this high-risk patient population. We have previously published that LKB1 acts to limit focal adhesion kinase (FAK) activity in human lung cancer cells to restrict cell adhesion and migration. Based on our prior published data we hypothesize that FAK pathway inhibition will suppress invasion and metastasis in LKB1-mutant tumors in vivo. To investigate our hypothesis, we have designed the first rolling-enrollment pre-clinical mouse trial to target invasion and metastasis using a small-molecule FAK inhibitor. To enroll mice with early-stage lung adenocarcinoma, we developed a novel lentiviral-Cre induced KrasG12D; Lkb1fl/fl genetically engineered mouse model (GEMM) (KLLLenti) that develops 100% adenocarcinomas, expresses a luciferase reporter gene, and has elevated levels of active FAK in late stage invasive tumors. Importantly, short-term treatment of KLLLenti mice with a pharmacologic FAK inhibitor potently suppresses the invasive progression of primary tumors. Moreover, long-term treatment results in improved progression-free survival, and delays metastatic spread to the lymph nodes. We further pursue mechanistic studies to investigate how LKB1-mutant tumor tissue gains a metastatic advantage in vivo, and using a combination of 3D tumor spheroid assays, and multiphoton microscopy, present results that LKB1-mutant tumors use a unique form of hybrid invasion that relies both on cell:cell and cell-matrix adhesion, and in doing so, are equipped to more efficiently invade into the collagen-dense microenvironment of the lung. We will also present data that similar molecular and cell biologic phenotypes can be found in a subset of KRAS, LKB1-mutant human clinical samples. Our studies suggest that when used early, FAK inhibitors may be a viable clinical strategy to prevent or delay metastasis in the KRAS, LKB1-mutant patient population, and begin to define alternate escape pathways by which this highly invasive cell population may escape first-line therapy.
Citation Format: Melissa Gilbert-Ross, Jessica Konen, Junghui Koo, John Shupe, Gabriel L. Sica, Zhengjia Chen, Brian S. Robinson, Madhusmita Behera, Michael R. Rossi, Geoffrey H. Smith, Charles E. Hill, Suresh M. Ramalingam, Haian Fu, Fadlo R. Khuri, Wei Zhou, Adam Marcus. Developing a personalized anti-metastatic therapy to treat KRAS, LKB1-mutant lung adenocarcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-348.
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Affiliation(s)
| | - Jessica Konen
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | - Junghui Koo
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | - John Shupe
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | - Gabriel L. Sica
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | - Zhengjia Chen
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | | | | | | | | | - Charles E. Hill
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | | | - Haian Fu
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | | | - Wei Zhou
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
| | - Adam Marcus
- 1The Winship Cancer Institute of Emory University, Atlanta, GA
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Song D, Robinson BS, Granacki JJ, Berger TW. Implementing spiking neuron model and spike-timing-dependent plasticity with generalized Laguerre-Volterra models. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2014:714-7. [PMID: 25570058 DOI: 10.1109/embc.2014.6943690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To perform large-scale simulations of the brain or build biologically-inspired cognitive architectures, it is essential to have a succinct and flexible model of spiking neurons. The model should be able to capture the nonlinear dynamical properties of various types of neurons and the nonstationary properties such as the spike-timing-dependent plasticity (STDP). In this paper, we propose a generalized Laguerre-Volterra modeling approach for such a task. Due to its built-in nonlinear dynamical terms, the generalized Laguerre-Volterra model (GLVM) can capture various biological processes/mechanisms. Using Laguerre expansion of Volterra kernel technique, the model is fully represented with a small set of coefficients. The calculation of the model variables can be expressed recursively based on only the current and the one-step-before values and thus can be performed efficiently. In addition, we show that, using the same methodology, STDP can be implemented as a specific form of second-order Volterra kernel describing the causal relationship between pairs of input-output spikes and the changes of the feedforward kernels in the GLVMs.
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Robinson BS, Song D, Berger TW. Estimation of a large-scale generalized Volterra model for neural ensembles with group lasso and local coordinate descent. Annu Int Conf IEEE Eng Med Biol Soc 2016; 2015:2526-9. [PMID: 26736806 DOI: 10.1109/embc.2015.7318906] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Estimation of neural models based on observed spike timing faces challenges as the amount of recorded units increases, especially when identifying detailed model features. Given that neural regions are generally sparsely connected, input selection is a critical step in model estimation but oftentimes computationally and theoretically challenging. In this paper, we detail an efficient methodology for estimating a sparse, nonlinear dynamical multiple-input, single-output model (MISO) applicable to large-scale (n > 50) single-unit recorded activity. The main contribution of this paper is the complete implementation of a principled group-lasso and local coordinate descent (LCD) algorithm into a generalized Volterra model (GVM) framework to achieve efficient sparse model estimation. Input selection is achieved with group-lasso by simultaneously selecting groups of parameters that are associated with each input. LCD yields efficient computation as the amount of inputs and parameters increase. We investigate and validate the performance of this estimation procedure with the application to a 64 input simulated model.
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Robinson BS, Song D, Berger TW. Generalized Volterra kernel model identification of spike-timing-dependent plasticity from simulated spiking activity. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2014:6585-8. [PMID: 25571505 DOI: 10.1109/embc.2014.6945137] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This paper presents a methodology to estimate a learning rule that governs activity-dependent plasticity from behaviorally recorded spiking events. To demonstrate this framework, we simulate a probabilistic spiking neuron with spike-timing-dependent plasticity (STDP) and estimate all model parameters from the simulated spiking data. In the neuron model, output spiking activity is generated by the combination of noise, feedback from the output, and an input-feedforward component whose magnitude is modulated by synaptic weight. The synaptic weight is calculated with STDP with the following features: (1) weight change based on the relative timing of input-output spike pairs, (2) prolonged plasticity induction, and (3) considerations for system stability. Estimation of all model parameters is achieved iteratively by formulating the model as a generalized linear model with Volterra kernels and basis function expansion. Successful estimation of all model parameters in this study demonstrates the feasibility of this approach for in-vivo experimental studies. Furthermore, the consideration of system stability and prolonged plasticity induction enhances the ability to capture how STDP affects a neural population's signal transformation properties over a realistic time course. Plasticity characterization with this estimation method could yield insights into functional implications of STDP and be incorporated into a cortical prosthesis.
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Robinson BS, Song D, Berger TW. Laguerre-Volterra identification of spike-timing-dependent plasticity from spiking activity: a simulation study. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2013:5578-81. [PMID: 24111001 DOI: 10.1109/embc.2013.6610814] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This paper presents a Laguerre-Volterra methodology for identifying a plasticity learning rule from spiking neural data with four components: 1) By analyzing input-output spiking data, the effective contribution of an input on the output firing probability can be quantified with weighted Volterra kernels. 2) The weight of these Volterra kernels can be tracked over time using the stochastic state point processing filtering algorithm (SSPPF) 3) Plasticity system Volterra kernels can be estimated by treating the tracked change in weight over time as the plasticity system output and the spike timing data as the input. 4) Laguerre expansion of all Volterra kernels allows for minimization of open parameters during estimation steps. A single input spiking neuron with Spike-timing-dependent plasticity (STDP) and prolonged STDP induction is simulated. Using the spiking data from this simulation, the amplitude of the STDP learning rule and the time course of the induction is accurately estimated. This framework can be applied to identify plasticity for more complicated plasticity paradigms and is applicable to in vivo data.
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Zhang C, Robinson BS, Xu W, Yang L, Yao B, Zhao H, Byun PK, Jin P, Veraksa A, Moberg KH. The ecdysone receptor coactivator Taiman links Yorkie to transcriptional control of germline stem cell factors in somatic tissue. Dev Cell 2015; 34:168-80. [PMID: 26143992 DOI: 10.1016/j.devcel.2015.05.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Revised: 04/25/2015] [Accepted: 05/14/2015] [Indexed: 12/16/2022]
Abstract
The Hippo pathway is a conserved signaling cascade that modulates tissue growth. Although its core elements are well defined, factors modulating Hippo transcriptional outputs remain elusive. Here we show that components of the steroid-responsive ecdysone (Ec) pathway modulate Hippo transcriptional effects in imaginal disc cells. The Ec receptor coactivator Taiman (Tai) interacts with the Hippo transcriptional coactivator Yorkie (Yki) and promotes expression of canonical Yki-responsive genes. Tai enhances Yki-driven growth, while Tai loss, or a form of Tai unable to bind Yki, suppresses Yki-driven tissue growth. This growth suppression is not correlated with impaired induction of canonical Hippo-responsive genes but with suppression of a distinct pro-growth program of Yki-induced/Tai-dependent genes, including the germline stem cell factors nanos and piwi. These data reveal Hippo/Ec pathway crosstalk in the form a Yki-Tai complex that collaboratively induces germline genes as part of a transcriptional program that is normally repressed in developing somatic epithelia.
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Affiliation(s)
- Can Zhang
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Brian S Robinson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Pathology & Laboratory Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Wenjian Xu
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Liu Yang
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Bing Yao
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Heya Zhao
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Phil K Byun
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA; Graduate Program in Genetics and Molecular Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Peng Jin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Alexey Veraksa
- Department of Biology, University of Massachusetts Boston, Boston, MA 02125, USA
| | - Kenneth H Moberg
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Song D, Robinson BS, Hampson RE, Marmarelis VZ, Deadwyler SA, Berger TW. Sparse generalized volterra model of human hippocampal spike train transformation for memory prostheses. Annu Int Conf IEEE Eng Med Biol Soc 2015; 2015:3961-3964. [PMID: 26737161 DOI: 10.1109/embc.2015.7319261] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In order to build hippocampal prostheses for restoring memory functions, we build multi-input, multi-output (MIMO) nonlinear dynamical models of the human hippocampus. Spike trains are recorded from the hippocampal CA3 and CA1 regions of epileptic patients performing a memory-dependent delayed match-to-sample task. Using CA3 and CA1 spike trains as inputs and outputs respectively, second-order sparse generalized Laguerre-Volterra models are estimated with group lasso and local coordinate descent methods to capture the nonlinear dynamics underlying the spike train transformations. These models can accurately predict the CA1 spike trains based on the ongoing CA3 spike trains and thus will serve as the computational basis of the hippocampal memory prosthesis.
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Song D, Chan RHM, Robinson BS, Marmarelis VZ, Opris I, Hampson RE, Deadwyler SA, Berger TW. Identification of functional synaptic plasticity from spiking activities using nonlinear dynamical modeling. J Neurosci Methods 2014; 244:123-35. [PMID: 25280984 DOI: 10.1016/j.jneumeth.2014.09.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2014] [Revised: 09/23/2014] [Accepted: 09/23/2014] [Indexed: 11/30/2022]
Abstract
This paper presents a systems identification approach for studying the long-term synaptic plasticity using natural spiking activities. This approach consists of three modeling steps. First, a multi-input, single-output (MISO), nonlinear dynamical spiking neuron model is formulated to estimate and represent the synaptic strength in means of functional connectivity between input and output neurons. Second, this MISO model is extended to a nonstationary form to track the time-varying properties of the synaptic strength. Finally, a Volterra modeling method is used to extract the synaptic learning rule, e.g., spike-timing-dependent plasticity, for the explanation of the input-output nonstationarity as the consequence of the past input-output spiking patterns. This framework is developed to study the underlying mechanisms of learning and memory formation in behaving animals, and may serve as the computational basis for building the next-generation adaptive cortical prostheses.
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Affiliation(s)
- Dong Song
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
| | - Rosa H M Chan
- Department of Electronic Engineering, City University of Hong Kong, Hong Kong, China.
| | - Brian S Robinson
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
| | - Vasilis Z Marmarelis
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
| | - Ioan Opris
- Department of Physiology & Pharmacology, Wake Forest University, School of Medicine, Winston-Salem, NC 27157, USA.
| | - Robert E Hampson
- Department of Physiology & Pharmacology, Wake Forest University, School of Medicine, Winston-Salem, NC 27157, USA.
| | - Sam A Deadwyler
- Department of Physiology & Pharmacology, Wake Forest University, School of Medicine, Winston-Salem, NC 27157, USA.
| | - Theodore W Berger
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
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Hendrickson PJ, Yu GJ, Robinson BS, Song D, Berger TW. The contribution of relative activation levels between populations of cells to network activity in a large-scale biologically realistic model of the hippocampus. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:5962-5. [PMID: 24111097 DOI: 10.1109/embc.2013.6610910] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In previously published work, we showed the progress we've made towards creating a large-scale, biologically realistic model of the rat hippocampus, starting with the projection from entorhinal cortex (EC) to the dentate gyrus (DG). We created the model to help us study how the common components of neurobiological systems in mammals - large numbers of neurons with intricate, branching morphologies; active, non-linear membrane properties; nonuniform distributions throughout membrane surface of these non-linear conductances; non-uniform and topographic connectivity between pre- and post-synaptic neurons; and activity-dependent changes in synaptic function - combine and contribute to give a particular brain region its "neural processing" properties. In this work, we report on the results of a series of simulations we ran to test the role of feed-forward and feedback inhibition in the dentate gyrus. We find that a) the system shows rhythmic bands of activity only in the presence of feedback inhibition, b) that the frequency of rhythmicity increases with increasing amounts of feed-forward inhibition, c) that it decreases with increasing amounts of feedback inhibition, and d) that strong excitatory inputs appear to enhance and prolong the amount of rhythmicity in the system.
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Yu GJ, Hendrickson PJ, Robinson BS, Song D, Berger TW. The role of topography in the transformation of spatiotemporal patterns by a large-scale, biologically realistic model of the rat dentate gyrus. Annu Int Conf IEEE Eng Med Biol Soc 2013; 2013:5950-3. [PMID: 24111094 PMCID: PMC4156021 DOI: 10.1109/embc.2013.6610907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A large-scale, biologically realistic, computational model of the rat hippocampus is being constructed to study the input-output transformation that the hippocampus performs. In the initial implementation, the layer II entorhinal cortex neurons, which provide the major input to the hippocampus, and the granule cells of the dentate gyrus, which receive the majority of the input, are modeled. In a previous work, the topography, or the wiring diagram, connecting these two populations had been derived and implemented. This paper explores the consequences of two features of the topography, the distribution of the axons and the size of the neurons' axon terminal fields. The topography converts streams of independently generated random Poisson trains into structured spatiotemporal patterns through spatiotemporal convergence achievable by overlapping axon terminal fields. Increasing the axon terminal field lengths allowed input to converge over larger regions of space resulting in granule activation across a greater area but did not increase the total activity as a function of time as the number of targets per input remained constant. Additional simulations demonstrated that the total distribution of spikes in space depends not on the distribution of the presynaptic axons but the distribution of the postsynaptic population. Analyzing spike counts emphasizes the importance of the postsynaptic distribution, but it ignores the fact that each individual input may be carrying unique information. Therefore, a metric should be created that relates and tracks individual inputs as they are propagated and integrated through hippocampus.
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Hendrickson PJ, Yu GJ, Robinson BS, Song D, Berger TW. Towards a large-scale biologically realistic model of the hippocampus. Annu Int Conf IEEE Eng Med Biol Soc 2012; 2012:4595-4598. [PMID: 23366951 PMCID: PMC4172354 DOI: 10.1109/embc.2012.6346990] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Real neurobiological systems in the mammalian brain have a complicated and detailed structure, being composed of 1) large numbers of neurons with intricate, branching morphologies--complex morphology brings with it complex passive membrane properties; 2) active membrane properties--nonlinear sodium, potassium, calcium, etc. conductances; 3) non-uniform distributions throughout the dendritic and somal membrane surface of these non-linear conductances; 4) non-uniform and topographic connectivity between pre- and post-synaptic neurons; and 5) activity-dependent changes in synaptic function. One of the essential, and as yet unanswered questions in neuroscience is the role of these fundamental structural and functional features in determining "neural processing" properties of a given brain system. To help answer that question, we're creating a large-scale biologically realistic model of the intrinsic pathway of the hippocampus, which consists of the projection from layer II entorhinal cortex (EC) to dentate gyrus (DG), EC to CA3, DG to CA3, and CA3 to CA1. We describe the computational hardware and software tools the model runs on, and demonstrate its viability as a modeling platform with an EC-to-DG model.
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Yu GJ, Robinson BS, Hendrickson PJ, Song D, Berger TW. Implementation of topographically constrained connectivity for a large-scale biologically realistic model of the hippocampus. Annu Int Conf IEEE Eng Med Biol Soc 2012; 2012:1358-61. [PMID: 23366151 PMCID: PMC4172365 DOI: 10.1109/embc.2012.6346190] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In order to understand how memory works in the brain, the hippocampus is highly studied because of its role in the encoding of long-term memories. We have identified four characteristics that would contribute to the encoding process: the morphology of the neurons, their biophysics, synaptic plasticity, and the topography connecting the input to and the neurons within the hippocampus. To investigate how long-term memory is encoded, we are constructing a large-scale biologically realistic model of the rat hippocampus. This work focuses on how topography contributes to the output of the hippocampus. Generally, the brain is structured with topography such that the synaptic connections formed by an input neuron population are organized spatially across the receiving population. The first step in our model was to construct how entorhinal cortex inputs connect to the dentate gyrus of the hippocampus. We have derived realistic constraints from topographical data to connect the two cell populations. The details on how these constraints were applied are presented. We demonstrate that the spatial connectivity has a major impact on the output of the simulation, and the results emphasize the importance of carefully defining spatial connectivity in neural network models of the brain in order to generate relevant spatiotemporal patterns.
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Affiliation(s)
- Gene J. Yu
- G. J. Yu, B. S. Robinson, P. J. Hendrickson, D. Song and T. W. Berger are with the Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Brian S. Robinson
- G. J. Yu, B. S. Robinson, P. J. Hendrickson, D. Song and T. W. Berger are with the Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Phillip J. Hendrickson
- G. J. Yu, B. S. Robinson, P. J. Hendrickson, D. Song and T. W. Berger are with the Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Dong Song
- G. J. Yu, B. S. Robinson, P. J. Hendrickson, D. Song and T. W. Berger are with the Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Theodore W. Berger
- G. J. Yu, B. S. Robinson, P. J. Hendrickson, D. Song and T. W. Berger are with the Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
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Robinson BS, Yu GJ, Hendrickson PJ, Song D, Berger TW. Implementation of activity-dependent synaptic plasticity rules for a large-scale biologically realistic model of the hippocampus. Annu Int Conf IEEE Eng Med Biol Soc 2012; 2012:1366-9. [PMID: 23366153 PMCID: PMC4172364 DOI: 10.1109/embc.2012.6346192] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A large-scale computational model of the hippocampus should consider plasticity at different time scales in order to capture the non-stationary information processing behavior of the hippocampus more accurately. This paper presents a computational model that describes hippocampal long-term potentiation/depression (LTP/LTD) and short-term plasticity implemented in the NEURON simulation environment. The LTP/LTD component is based on spike-timing-dependent plasticity (STDP). The short-term plasticity component modifies a previously defined deterministic model at a population synapse level to a probabilistic model that can be implemented at a single synapse level. The plasticity mechanisms are validated and incorporated into a large-scale model of the entorhinal cortex projection to the dentate gyrus. Computational expense of the added plasticity was also evaluated and shown to increase simulation time by less than a factor of two. This model can be easily included in future large-scale hippocampal simulations to investigate the effects of LTP/LTD and short-term plasticity in conjunction with other biological considerations on system function.
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Affiliation(s)
- Brian S. Robinson
- Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Gene J. Yu
- Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Phillip J. Hendrickson
- Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Dong Song
- Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
| | - Theodore W. Berger
- Center for Neural Engineering, Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089 USA
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Robinson BS, Moberg KH. Drosophila endocytic neoplastic tumor suppressor genes regulate Sav/Wts/Hpo signaling and the c-Jun N-terminal kinase pathway. Cell Cycle 2011; 10:4110-8. [PMID: 22101275 DOI: 10.4161/cc.10.23.18243] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Genetic screens in the fruit fly Drosophila melanogaster have identified a class of neoplastic tumor suppressor genes (endocytic nTSGs), which encode proteins that localize to endosomes and facilitate the trafficking of membrane-bound receptors and adhesion molecules into the degradative lysosome. Loss of endocytic nTSGs transforms imaginal disc epithelia into highly proliferative, invasive tissues that fail to differentiate and display defects in cellular apicobasal polarity, adhesion and tissue architecture. As vertebrate homologs of some Drosophila nTSGs are linked to tumor formation, identifying molecular changes in signaling associated with nTSG loss could inform understanding of neoplastic transformation in vertebrates. Here we show that mutations in genes that act at multiple steps of the endolysosomal pathway lead to autonomous activation of the Sav/Wts/Hpo (SWH) transcriptional effector Yki (YAP/TAZ in vertebrates) and the Jun N-terminal kinase (JNK), which is known to promote Yki activity in cells with disrupted polarity. Yki and JNK activity are elevated by mutations at multiple steps in the endolysosomal pathway including mutations in the AP-2σ gene, which encodes a component of the AP-2 adaptor complex that recruits cargoes into clathrin-coated pits for subsequent internalization. Moreover, reduction of JNK activity can decrease elevated Yki-signaling caused by altered endocytosis. These studies reveal a broad requirement for components of the endocytic pathway in regulating SWH and JNK outputs, and place Drosophila endocytic nTSGs into a network that involving two major signaling pathways implicated in oncogenesis.
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Affiliation(s)
- Brian S Robinson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, USA
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Robinson BS, Huang J, Hong Y, Moberg KH. Crumbs regulates Salvador/Warts/Hippo signaling in Drosophila via the FERM-domain protein Expanded. Curr Biol 2010; 20:582-90. [PMID: 20362445 PMCID: PMC2855393 DOI: 10.1016/j.cub.2010.03.019] [Citation(s) in RCA: 264] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2009] [Revised: 03/11/2010] [Accepted: 03/11/2010] [Indexed: 01/15/2023]
Abstract
BACKGROUND Altered expression of apicobasal polarity factors is associated with cancer in vertebrates and tissue overgrowth in invertebrates, yet the mechanisms by which these factors affect growth-regulatory pathways are not well defined. We have tested the basis of an overgrowth phenotype driven by the Drosophila protein Crumbs (Crb), which nucleates an apical membrane complex that functionally interacts with the Par6/Par3/aPKC and Scrib/Dlg/Lgl apicobasal polarity complexes. RESULTS We find that Crb-driven growth is dependent upon the Salvador/Warts/Hippo (SWH) pathway and its transcriptional effector Yorkie (Yki). Expression of the Crb intracellular domain elevates Yki activity, and this correlates in tissues and cultured cells with loss of Expanded (Ex), an apically localized SWH component that inhibits Yki. Reciprocally, loss of crb elevates Ex levels, although this excess Ex does not concentrate to its normal location at apical junctions. The Ex-regulatory domain of Crb maps to the juxtamembrane FERM-binding motif (JM), a cytoskeletal interaction domain distinct from the PDZ-binding motif (PBM) through which Crb binds polarity factors. Expression of Crb-JM drives Yki activity and organ growth with little effect on tissue architecture, while Crb-PBM reciprocally produces tissue architectural defects without significant effect on Yki activity. CONCLUSIONS These studies identify Crb as a novel SWH regulator via JM-dependent effects on Ex levels and localization and suggest that discrete domains within Crb may allow it to integrate junctional polarity signals with a conserved growth pathway.
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Affiliation(s)
- Brian S. Robinson
- Department of Cell Biology, Emory University School of Medicine Atlanta, GA
| | - Juang Huang
- Department of Cell Biology and Physiology, University of Pittsburgh Medical School, Pittsburgh, PA
| | - Yang Hong
- Department of Cell Biology and Physiology, University of Pittsburgh Medical School, Pittsburgh, PA
| | - Kenneth H. Moberg
- Department of Cell Biology, Emory University School of Medicine Atlanta, GA
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Gilbert MM, Robinson BS, Moberg KH. Functional interactions between the erupted/tsg101 growth suppressor gene and the DaPKC and rbf1 genes in Drosophila imaginal disc tumors. PLoS One 2009; 4:e7039. [PMID: 19855819 PMCID: PMC2739425 DOI: 10.1371/journal.pone.0007039] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Accepted: 08/19/2009] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND The Drosophila gene erupted (ept) encodes the fly homolog of human Tumor Susceptibility Gene-101 (TSG101), which functions as part of the conserved ESCRT-1 complex to facilitate the movement of cargoes through the endolysosomal pathway. Loss of ept or other genes that encode components of the endocytic machinery (e.g. synatxin7/avalanche, rab5, and vps25) produces disorganized overgrowth of imaginal disc tissue. Excess cell division is postulated to be a primary cause of these 'neoplastic' phenotypes, but the autonomous effect of these mutations on cell cycle control has not been examined. PRINCIPAL FINDINGS Here we show that disc cells lacking ept function display an altered cell cycle profile indicative of deregulated progression through the G1-to-S phase transition and express reduced levels of the tumor suppressor ortholog and G1/S inhibitor Rbf1. Genetic reductions of the Drosophila aPKC kinase (DaPKC), which has been shown to promote tumor growth in other fly tumor models, prevent both the ept neoplastic phenotype and the reduction in Rbf1 levels that otherwise occurs in clones of ept mutant cells; this effect is coincident with changes in localization of Notch and Crumbs, two proteins whose sorting is altered in ept mutant cells. The effect on Rbf1 can also be blocked by removal of the gamma-secretase component presenilin, suggesting that cleavage of a gamma-secretase target influences Rbf1 levels in ept mutant cells. Expression of exogenous rbf1 completely ablates ept mutant eye tissues but only mildly affects the development of discs composed of cells with wild type ept. CONCLUSIONS Together, these data show that loss of ept alters nuclear cell cycle control in developing imaginal discs and identify the DaPKC, presenilin, and rbf1 genes as modifiers of molecular and cellular phenotypes that result from loss of ept.
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Affiliation(s)
- M. Melissa Gilbert
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Brian S. Robinson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Kenneth H. Moberg
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
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Gilbert MM, Beam CK, Robinson BS, Moberg KH. Genetic interactions between the Drosophila tumor suppressor gene ept and the stat92E transcription factor. PLoS One 2009; 4:e7083. [PMID: 19787055 PMCID: PMC2747001 DOI: 10.1371/journal.pone.0007083] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Accepted: 08/19/2009] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Tumor Susceptibility Gene-101 (TSG101) promotes the endocytic degradation of transmembrane proteins and is implicated as a mutational target in cancer, yet the effect of TSG101 loss on cell proliferation in vertebrates is uncertain. By contrast, Drosophila epithelial tissues lacking the TSG101 ortholog erupted (ept) develop as enlarged undifferentiated tumors, indicating that the gene can have anti-growth properties in a simple metazoan. A full understanding of pathways deregulated by loss of Drosophila ept will aid in understanding potential links between mammalian TSG101 and growth control. PRINCIPAL FINDINGS We have taken a genetic approach to the identification of pathways required for excess growth of Drosophila eye-antennal imaginal discs lacking ept. We find that this phenotype is very sensitive to the genetic dose of stat92E, the transcriptional effector of the Jak-Stat signaling pathway, and that this pathway undergoes strong activation in ept mutant cells. Genetic evidence indicates that stat92E contributes to cell cycle deregulation and excess cell size phenotypes that are observed among ept mutant cells. In addition, autonomous Stat92E hyper-activation is associated with altered tissue architecture in ept tumors and an effect on expression of the apical polarity determinant crumbs. CONCLUSIONS These findings identify ept as a cell-autonomous inhibitor of the Jak-Stat pathway and suggest that excess Jak-Stat signaling makes a significant contribution to proliferative and tissue architectural phenotypes that occur in ept mutant tissues.
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Affiliation(s)
- M. Melissa Gilbert
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Carolyn K. Beam
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Brian S. Robinson
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
| | - Kenneth H. Moberg
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, United States of America
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Stevens ML, Caplan DO, Robinson BS, Boroson DM, Kachelmyer AL. Optical homodyne PSK demonstration of 1.5 photons per bit at 156 Mbps with rate-(1/2) turbo coding. Opt Express 2008; 16:10412-10420. [PMID: 18607453 DOI: 10.1364/oe.16.010412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We report the first demonstration of a near quantum-limited optical homodyne PSK receiver combined with powerful forward-error-correction coding, achieving 1.5 photons/bit sensitivity, within 4.5 dB of the Shannon limit. Phase-locking was achieved at 1.55 microm using an analog dither-based optical phase-locked loop with an external phase modulator. Analysis for this configuration with arbitrary loop damping is given showing a performance advantage for the overdamped case.
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Affiliation(s)
- M L Stevens
- Optical Communication Technology Group, MIT Lincoln Laboratory, 244 Wood St, Lexington, MA 02420, USA.
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Libertini SJ, Robinson BS, Dhillon NK, Glick D, George M, Dandekar S, Gregg JP, Sawai E, Mudryj M. Cyclin E Both Regulates and Is Regulated by Calpain 2, a Protease Associated with Metastatic Breast Cancer Phenotype. Cancer Res 2005; 65:10700-8. [PMID: 16322214 DOI: 10.1158/0008-5472.can-05-1666] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Overexpression of cyclin E in breast tumors is associated with a poor response to tamoxifen therapy, greater genomic instability, more aggressive behavior, and a poor clinical prognosis. These tumors also express low molecular weight isoforms of cyclin E that are associated with higher kinase activity and increased metastatic potential. In the current study, we show that cyclin E overexpression in MCF7 cells transactivates the expression of calpain 2, leading to proteolysis of cyclin E as well as several known calpain substrates including focal adhesion kinase (FAK), calpastatin, pp60src, and p53. In vivo inhibition of calpain activity in MCF7-cyclin E cells impedes cyclin E proteolysis, whereas in vivo induction of calpain activity promotes cyclin E proteolysis. An analysis of human breast tumors shows that high levels of cyclin E are coincident with the expression of the low molecular weight isoforms, high levels of calpain 2 protein, and proteolysis of FAK. Lastly, studies using a mouse model of metastasis reveal that highly metastatic tumors express proteolyzed cyclin E and FAK when compared to tumors with a low metastatic potential. Our results suggest that cyclin E–dependent deregulation of calpain may be pivotal in modifying multiple cellular processes that are instrumental in the etiology and progression of breast cancer.
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Affiliation(s)
- Stephen J Libertini
- Department of Medical Microbiology and Immunology, University of California, Davis, Davis, California 95616, USA
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Abstract
In developing a screening assay for a serine/threonine kinase, we evaluated various formats of an in-plate enzyme-linked immunosorbent assay (ELISA), as well as solution-phase kinase assays using either ELISA or AlphaScreen detection. Substrate was available both as a biotinylated 15-residue peptide and as a 25-residue peptide containing the same sequence expressed as a glutathione S-transferase fusion protein. When increasing concentrations of either of these substrates were coated directly onto ELISA plates, the rates of the kinase reactions progressively increased. In contrast, when the biotin-peptide was captured onto NeutrAvidin-coated plates, the finite peptide binding capacity of the plates limited the amount of substrate that could be incorporated into the assay system and thereby limited the rate of the reaction at a given kinase concentration. Solution-phase kinase reactions can tolerate high substrate concentrations; however, analysis of kinase reaction samples containing biotin-peptide concentrations higher than the binding capacity of NeutrAvidin-coated plates resulted in an inability to detect differences between reactions run at different substrate concentrations. For AlphaScreen detection following solution-phase kinase reactions, limitations in the binding capacity of the donor and acceptor beads caused loss of signal for substrate concentrations above the maximum binding capacity. Overall, the solution-phase assays required significantly more kinase than the in-plate assays (1-4 microg/ml versus <100 ng/ml, respectively). These studies demonstrate that the amount of substrate that can be incorporated into an assay system substantially affects the rate of the kinase reaction and therefore the amount of kinase required for the assay.
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Affiliation(s)
- Laura E DeForge
- Department of Assay and Automation Technology, Genentech, Inc., South San Francisco, CA, USA.
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Costabile M, Hii CS, Robinson BS, Rathjen DA, Pitt M, Easton C, Miller RC, Poulos A, Murray AW, Ferrante A. A novel long chain polyunsaturated fatty acid, beta-Oxa 21:3n-3, inhibits T lymphocyte proliferation, cytokine production, delayed-type hypersensitivity, and carrageenan-induced paw reaction and selectively targets intracellular signals. J Immunol 2001; 167:3980-7. [PMID: 11564817 DOI: 10.4049/jimmunol.167.7.3980] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A novel polyunsaturated fatty acid (PUFA), beta-oxa 21:3n-3, containing an oxygen atom in the beta position, was chemically synthesized, and found to have more selective biological activity than the n-3 PUFA, docosahexaenoic acid (22:6n-3) on cells of the immune system. Although beta-oxa 21:3n-3 was very poor compared with 22:6n-3 at stimulating oxygen radical production in neutrophils, it was more effective at inhibiting human T lymphocyte proliferation (IC(50) of 1.9 vs 5.2 microM, respectively). beta-Oxa 21:3n-3 also inhibited the production of TNF-beta, IFN-gamma, and IL-2 by purified human T lymphocytes stimulated with PHA plus PMA, anti-CD3 plus anti-CD28 mAbs, or PMA plus A23187. Metabolism of beta-oxa 21:3n-3 via the cyclooxygenase and lipoxygenase pathways was not required for its inhibitory effects. Consistent with its ability to suppress T lymphocyte function, beta-oxa 21:3n-3 significantly inhibited the delayed-type hypersensitivity response and carrageenan-induced paw edema in mice. In T lymphocytes, beta-oxa 21:3n-3 inhibited the agonist-stimulated translocation of protein kinase C-betaI and -epsilon, but not -alpha, -betaII, or -theta to a particulate fraction, and also inhibited the activation of the extracellular signal-regulated protein kinase, but not c-Jun NH(2)-terminal kinase and p38. In contrast, 22:6n-3 had no effects on these protein kinase C isozymes. The increase in antiinflammatory activity and loss of unwanted bioaction through the generation of a novel synthetic 22:6n-3 analogue provides evidence for a novel strategy in the development of anti-inflammatory agents by chemically engineering PUFA.
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Affiliation(s)
- M Costabile
- Department of Immunopathology and Paediatrics, University of Adelaide, Women's and Children's Hospital, 72 King William Road, North Adelaide, 5006 South Australia
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De Jonckheere JF, Brown S, Dobson PJ, Robinson BS, Pernin P. The amoeba-to-flagellate transformation test is not reliable for the diagnosis of the genus Naegleria. Description of three new Naegleria spp. Protist 2001; 152:115-21. [PMID: 11545434 DOI: 10.1078/1434-4610-00049] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Trophozoites of several isolates from one location in Australia have failed consistently to transform into flagellates, although they display all other characteristics of the genus Naegleria. When changing the standard transformation test, flagellates were produced. In phylogenetic trees derived from partial small subunit ribosomal DNA (SSUrDNA) sequences, one of these strains branches close to a cluster comprising N. clarki, N. australiensis, N. italica and N. jadini. It is proposed that these Australian isolates represent a new species, named N. fultoni (strain NG885). Failing to form flagellates since their isolation, even when different transformation procedures are used, are two Naegleria strains from Chile and Indonesia. In SSUrDNA-based phylogenetic trees the Chilean strain clusters with N. pussardi and the Indonesian strain clusters with N. galeacystis, but the degree of sequence difference from these described species (3.5% and 2.2%, respectively) is sufficient to propose that both of the strains represent new species, named N. chilensis (strain NG946) and N. indonesiensis (strain NG945), respectively. The close relationships between each of the new species and the Naegleria species with which they cluster in SSUrDNA-based trees were confirmed by ribosomal internal transcribed spacer region (ITS) sequence comparisons. In France, several non-flagellating N. fowleri strains were isolated from one location. ITS rDNA sequence comparisons indicated that they correspond to a 'type' of N. fowleri found in both Europe and the USA. A redefinition of the genus Naegleria is proposed as a consequence of these and previous findings.
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Gong YF, Robinson BS, Rose RE, Deminie C, Spicer TP, Stock D, Colonno RJ, Lin PF. In vitro resistance profile of the human immunodeficiency virus type 1 protease inhibitor BMS-232632. Antimicrob Agents Chemother 2000; 44:2319-26. [PMID: 10952574 PMCID: PMC90064 DOI: 10.1128/aac.44.9.2319-2326.2000] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
BMS-232632 is an azapeptide human immunodeficiency virus (HIV) type 1 (HIV-1) protease inhibitor that displays potent anti-HIV-1 activity (50% effective concentration [EC(50)], 2.6 to 5.3 nM; EC(90), 9 to 15 nM). In vitro passage of HIV-1 RF in the presence of inhibitors showed that BMS-232632 selected for resistant variants more slowly than nelfinavir or ritonavir did. Genotypic and phenotypic analysis of three different HIV strains resistant to BMS-232632 indicated that an N88S substitution in the viral protease appeared first during the selection process in two of the three strains. An I84V change appeared to be an important substitution in the third strain used. Mutations were also observed at the protease cleavage sites following drug selection. The evolution to resistance seemed distinct for each of the three strains used, suggesting multiple pathways to resistance and the importance of the viral genetic background. A cross-resistance study involving five other protease inhibitors indicated that BMS-232632-resistant virus remained sensitive to saquinavir, while it showed various levels (0. 1- to 71-fold decrease in sensitivity)-of cross-resistance to nelfinavir, indinavir, ritonavir, and amprenavir. In reciprocal experiments, the BMS-232632 susceptibility of HIV-1 variants selected in the presence of each of the other HIV-1 protease inhibitors showed that the nelfinavir-, saquinavir-, and amprenavir-resistant strains of HIV-1 remained sensitive to BMS-232632, while indinavir- and ritonavir-resistant viruses displayed six- to ninefold changes in BMS-232632 sensitivity. Taken together, our data suggest that BMS-232632 may be a valuable protease inhibitor for use in combination therapy.
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Affiliation(s)
- Y F Gong
- Departments of Virology, Bristol-Myers Squibb Company, Wallingford, Connecticut 06492, USA
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