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Rangarajan S, Locy ML, Chanda D, Kurundkar A, Kurundkar D, Larson-Casey JL, Londono P, Bagchi RA, Deskin B, Elajaili H, Nozik ES, Deshane JS, Zmijewski JW, Eickelberg O, Thannickal VJ. Mitochondrial uncoupling protein-2 reprograms metabolism to induce oxidative stress and myofibroblast senescence in age-associated lung fibrosis. Aging Cell 2022; 21:e13674. [PMID: 35934931 PMCID: PMC9470902 DOI: 10.1111/acel.13674] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [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: 06/10/2021] [Revised: 06/12/2022] [Accepted: 07/04/2022] [Indexed: 01/25/2023] Open
Abstract
Mitochondrial dysfunction has been associated with age-related diseases, including idiopathic pulmonary fibrosis (IPF). We provide evidence that implicates chronic elevation of the mitochondrial anion carrier protein, uncoupling protein-2 (UCP2), in increased generation of reactive oxygen species, altered redox state and cellular bioenergetics, impaired fatty acid oxidation, and induction of myofibroblast senescence. This pro-oxidant senescence reprogramming occurs in concert with conventional actions of UCP2 as an uncoupler of oxidative phosphorylation with dissipation of the mitochondrial membrane potential. UCP2 is highly expressed in human IPF lung myofibroblasts and in aged fibroblasts. In an aging murine model of lung fibrosis, the in vivo silencing of UCP2 induces fibrosis regression. These studies indicate a pro-fibrotic function of UCP2 in chronic lung disease and support its therapeutic targeting in age-related diseases associated with impaired tissue regeneration and organ fibrosis.
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Affiliation(s)
- Sunad Rangarajan
- Division of Pulmonary Sciences and Critical Care, Department of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Morgan L Locy
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Diptiman Chanda
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Ashish Kurundkar
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Deepali Kurundkar
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jennifer L Larson-Casey
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Pilar Londono
- Division of Pulmonary Sciences and Critical Care, Department of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Rushita A Bagchi
- Division of Cardiology, Department of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Brian Deskin
- Division of Pulmonary and Critical Care, Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Hanan Elajaili
- Cardiovascular Pulmonary Research Laboratories and Pediatric Critical Care Medicine, Department of Pediatrics, University of Colorado, Aurora, Colorado, USA
| | - Eva S Nozik
- Cardiovascular Pulmonary Research Laboratories and Pediatric Critical Care Medicine, Department of Pediatrics, University of Colorado, Aurora, Colorado, USA
| | - Jessy S Deshane
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jaroslaw W Zmijewski
- Division of Pulmonary and Critical Care, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Oliver Eickelberg
- Division of Pulmonary, Allergy and Critical Care, Department of Medicine, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Victor J Thannickal
- John W. Deming Department of Medicine, Tulane University School of Medicine, New Orleans, Louisiana, USA
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Knight WE, Cao Y, Lin YH, Chi C, Bai B, Sparagna GC, Zhao Y, Du Y, Londono P, Reisz JA, Brown BC, Taylor MRG, Ambardekar AV, Cleveland JC, McKinsey TA, Jeong MY, Walker LA, Woulfe KC, D'Alessandro A, Chatfield KC, Xu H, Bristow MR, Buttrick PM, Song K. Maturation of Pluripotent Stem Cell-Derived Cardiomyocytes Enables Modeling of Human Hypertrophic Cardiomyopathy. Stem Cell Reports 2021; 16:519-533. [PMID: 33636116 PMCID: PMC7940251 DOI: 10.1016/j.stemcr.2021.01.018] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [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: 01/23/2020] [Revised: 01/26/2021] [Accepted: 01/27/2021] [Indexed: 12/20/2022] Open
Abstract
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are a powerful platform for biomedical research. However, they are immature, which is a barrier to modeling adult-onset cardiovascular disease. Here, we sought to develop a simple method that could drive cultured hiPSC-CMs toward maturity across a number of phenotypes, with the aim of utilizing mature hiPSC-CMs to model human cardiovascular disease. hiPSC-CMs were cultured in fatty acid-based medium and plated on micropatterned surfaces. These cells display many characteristics of adult human cardiomyocytes, including elongated cell morphology, sarcomeric maturity, and increased myofibril contractile force. In addition, mature hiPSC-CMs develop pathological hypertrophy, with associated myofibril relaxation defects, in response to either a pro-hypertrophic agent or genetic mutations. The more mature hiPSC-CMs produced by these methods could serve as a useful in vitro platform for characterizing cardiovascular disease. Standard (glucose) cultured hiPSC-CMs demonstrate a blunted hypertrophic response A maturation method induces hiPSC-CM maturation and suppresses HIF1A expression Mature hiPSC-CMs demonstrate improved sarcomeric morphology and contractility Mature hiPSC-CMs respond to agonist- or mutation-induced hypertrophy
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Affiliation(s)
- Walter E Knight
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Yingqiong Cao
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Ying-Hsi Lin
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Congwu Chi
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Betty Bai
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Genevieve C Sparagna
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Yuanbiao Zhao
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Yanmei Du
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Pilar Londono
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Benjamin C Brown
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Matthew R G Taylor
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Amrut V Ambardekar
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Joseph C Cleveland
- The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Department of Surgery, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Timothy A McKinsey
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Mark Y Jeong
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Lori A Walker
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kathleen C Woulfe
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kathryn C Chatfield
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Hongyan Xu
- Department of Population Health Sciences, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Michael R Bristow
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Peter M Buttrick
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kunhua Song
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Gates Center for Regenerative Medicine and Stem Cell Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; The Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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3
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Riching AS, Major JL, Londono P, Bagchi RA. The Brain-Heart Axis: Alzheimer's, Diabetes, and Hypertension. ACS Pharmacol Transl Sci 2019; 3:21-28. [PMID: 32259085 DOI: 10.1021/acsptsci.9b00091] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Indexed: 01/15/2023]
Abstract
Alzheimer's disease (AD) is a debilitating neurodegenerative disorder affecting millions worldwide. Currently, there are only four approved treatments for AD, which improve symptoms modestly. AD is believed to be caused by the formation of intercellular plaques and intracellular tangles in the brain, but thus far all new drugs which target these pathologies have failed clinical trials. New research highlights the link between AD and Type II Diabetes (T2D), and some believe that AD is actually a brain specific form of it termed Type III Diabetes (T3D). Drugs which are currently approved for the treatment of T2D, such as metformin, have shown promising results in improving cognitive function and even preventing the development of AD in diabetic patients. Recent studies shed light on the relationship between the brain and cardiovascular system in which the brain and heart communicate with one another via the vasculature to regulate fluid and nutrient homeostasis. This line of research reveals how the brain-heart axis regulates hypertension and diabetes, both of which can impact cognitive function. In this review we survey past and ongoing research and clinical trials for AD, and argue that AD is a complex and systemic disorder which requires comprehensive approaches beyond the brain for effective prevention and/or treatment.
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Affiliation(s)
- Andrew S Riching
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States.,Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States
| | - Jennifer L Major
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States.,Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States
| | - Pilar Londono
- Department of Medicine, Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States
| | - Rushita A Bagchi
- Department of Medicine, Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States.,Department of Pharmacology, University of Colorado Anschutz Medical Campus, Aurora, Colorado 80045, United States
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4
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Bagchi RA, Ferguson BS, Stratton MS, Hu T, Cavasin MA, Sun L, Lin YH, Liu D, Londono P, Song K, Pino MF, Sparks LM, Smith SR, Scherer PE, Collins S, Seto E, McKinsey TA. HDAC11 suppresses the thermogenic program of adipose tissue via BRD2. JCI Insight 2018; 3:120159. [PMID: 30089714 PMCID: PMC6129125 DOI: 10.1172/jci.insight.120159] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [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: 01/24/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022] Open
Abstract
Little is known about the biological function of histone deacetylase 11 (HDAC11), which is the lone class IV HDAC. Here, we demonstrate that deletion of HDAC11 in mice stimulates brown adipose tissue (BAT) formation and beiging of white adipose tissue (WAT). Consequently, HDAC11-deficient mice exhibit enhanced thermogenic potential and, in response to high-fat feeding, attenuated obesity, improved insulin sensitivity, and reduced hepatic steatosis. Ex vivo and cell-based assays revealed that HDAC11 catalytic activity suppresses the BAT transcriptional program, in both the basal state and in response to β-adrenergic receptor signaling, through a mechanism that is dependent on physical association with BRD2, a bromodomain and extraterminal (BET) acetyl-histone-binding protein. These findings define an epigenetic pathway for the regulation of energy homeostasis and suggest the potential for HDAC11-selective inhibitors for the treatment of obesity and diabetes.
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Affiliation(s)
- Rushita A. Bagchi
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | | | - Matthew S. Stratton
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Tianjing Hu
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Maria A. Cavasin
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lei Sun
- George Washington University Cancer Center, Washington, DC, USA
| | - Ying-Hsi Lin
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Dianxin Liu
- Integrative Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Pilar Londono
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Kunhua Song
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Maria F. Pino
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida, USA
| | - Lauren M. Sparks
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida, USA
| | - Steven R. Smith
- Translational Research Institute for Metabolism and Diabetes, Florida Hospital, Orlando, Florida, USA
| | - Philipp E. Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Sheila Collins
- Integrative Metabolism Program, Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, USA
| | - Edward Seto
- George Washington University Cancer Center, Washington, DC, USA
| | - Timothy A. McKinsey
- Department of Medicine, Division of Cardiology, and
- Consortium for Fibrosis Research & Translation, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
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5
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Riching AS, Zhao Y, Cao Y, Londono P, Xu H, Song K. Suppression of Pro-fibrotic Signaling Potentiates Factor-mediated Reprogramming of Mouse Embryonic Fibroblasts into Induced Cardiomyocytes. J Vis Exp 2018:57687. [PMID: 29912202 PMCID: PMC6101528 DOI: 10.3791/57687] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Trans-differentiation of one somatic cell type into another has enormous potential to model and treat human diseases. Previous studies have shown that mouse embryonic, dermal, and cardiac fibroblasts can be reprogrammed into functional induced-cardiomyocyte-like cells (iCMs) through overexpression of cardiogenic transcription factors including GATA4, Hand2, Mef2c, and Tbx5 both in vitro and in vivo. However, these previous studies have shown relatively low efficiency. In order to restore heart function following injury, mechanisms governing cardiac reprogramming must be elucidated to increase efficiency and maturation of iCMs. We previously demonstrated that inhibition of pro-fibrotic signaling dramatically increases reprogramming efficiency. Here, we detail methods to achieve a reprogramming efficiency of up to 60%. Furthermore, we describe several methods including flow cytometry, immunofluorescent imaging, and calcium imaging to quantify reprogramming efficiency and maturation of reprogrammed fibroblasts. Using the protocol detailed here, mechanistic studies can be undertaken to determine positive and negative regulators of cardiac reprogramming. These studies may identify signaling pathways that can be targeted to promote reprogramming efficiency and maturation, which could lead to novel cell therapies to treat human heart disease.
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Affiliation(s)
- Andrew S Riching
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus
| | - Yuanbiao Zhao
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus
| | - Yingqiong Cao
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus
| | - Pilar Londono
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus
| | - Hongyan Xu
- Department of Population Health Sciences, Medical College of Georgia, Augusta University
| | - Kunhua Song
- Division of Cardiology, Department of Medicine, University of Colorado Anschutz Medical Campus;
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Zhang L, Londono P, Yu L, Grimes S, Blackburn P, Gottlieb P, Eisenbarth GS. MAS-1 adjuvant immunotherapy generates robust Th2 type and regulatory immune responses providing long-term protection from diabetes in late-stage pre-diabetic NOD mice. Autoimmunity 2014; 47:341-50. [PMID: 24783965 DOI: 10.3109/08916934.2014.910768] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
MAS-1, a nanoparticular, emulsion-based adjuvant, was evaluated for its ability to promote Th2 and regulatory immune responses and prevent type 1 diabetes progression when given alone or as antigen-specific immunotherapy (ASI) using insulin B chain (IBC; MER3101) and its analog B:9-23(19Ala) (MER3102). MAS-1 formulations were administered to NOD mice at age 9 and 13 weeks and followed through 52 weeks. MER3101 and MER3102 provided long-term protection with 60% and 73% of mice remaining diabetes-free at week 35, and 60% and 47% at week 52. MAS-1 adjuvant emulsion by itself also provided protection with 60% and 40% of mice diabetes-free at 35 and 52 weeks, respectively. Higher levels of interleukin (IL)-10 and IL-2 positive T cells were detected among splenocytes by week 15 in MER3101 and MER3102 immunized mice, whereas MAS-1 alone induced higher levels of IL-10-positive T cells. Diabetes-free 52-week-old mice expressed significant levels of antigen-specific IL-10-positive type 1 regulatory T cells and FoxP3-positive T cells when stimulated ex vivo with IBC. Antibodies targeting IBC and B:9-23(19Ala) induced by MER3101 and MER3102 were overwhelmingly Th2 type IgG1 and IgG2b isotypes. Splenocyte cultures from 52 week diabetes-free, MER3101-treated mice secreted significantly increased levels of IL-4 and IL-5 Th2 cytokines. Based on these pre-clinical results and its clinical safety profile, MAS-1 has the requisite qualities to be considered for use in prophylactic or early stage disease settings to augment ASI to prevent disease progression in type 1 diabetes.
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Affiliation(s)
- Li Zhang
- Barbara Davis Center for Childhood Diabetes, University of Colorado , Aurora, CO , USA and
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Londono P, Komura A, Hara N, Zipris D. Brief dexamethasone treatment during acute infection prevents virus-induced autoimmune diabetes. Clin Immunol 2010; 135:401-11. [PMID: 20167539 DOI: 10.1016/j.clim.2010.01.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 01/19/2010] [Accepted: 01/19/2010] [Indexed: 10/19/2022]
Abstract
We used the LEW1.WR1 rat to test the hypothesis that Kilham rat virus-induced innate immune activation is involved in the mechanism of autoimmune diabetes. Animals were treated with dexamethasone, an anti-inflammatory glucocorticoid, beginning on the day of infection. Administering dexamethasone on five consecutive days completely blocked the disease. Strikingly, a single dose of dexamethasone was sufficient to prevent islet destruction. Dexamethasone downmodulated inflammation and restored normal ratios between CD8(+) and CD4(+)CD25(+)Foxp3(+) cells in the spleen. Finally, dexamethasone therapy lowered the frequency of splenic anti-virus CD8(+) T cells, but did not interfere with the ability of the host to generate anti-KRV antibodies and eliminate the virus from the spleen. Our data demonstrate a strong association between early virus-induced proinflammatory responses and islet destruction and raise the possibility that targeting innate immune pathways in the early stages of diabetes may be a useful strategy for disease prevention.
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Affiliation(s)
- Pilar Londono
- Barbara Davis Center for Childhood Diabetes, University of Colorado, Aurora, CO 80045, USA
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Street M, Herd K, Londono P, Doan T, Dougan G, Kast WM, Tindle RW. Differences in the effectiveness of delivery of B- and CTL-epitopes incorporated into the hepatitis B core antigen (HBcAg) c/e1-region. Arch Virol 1999; 144:1323-43. [PMID: 10481740 DOI: 10.1007/s007050050590] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 10/28/2022]
Abstract
Work from a number of laboratories including our own has shown that foreign B-epitopes inserted into the c/e1-region of Hepatitis B core antigen (HBcAg) elicit powerful antibody responses when mice are immunised with the recombinant core particles. In the present study, we wished to take advantage of the immunodominance of the c/e1-region to deliver cytotoxic T-lymphocyte (CTL) epitopes as a recombinant HBcAg vaccine. Our results indicated that recombinant HBcAg containing CTL epitopes of the E7 protein of human papillomavirus failed to prime E7-directed CTL responses when used to immunise mice for antigen processing through either the endogenous pathway via a Salmonella typhimurium vector, or through the exogenous pathway by parenteral immunisation with recombinant core. Hydropathicity plots predict that the presumed surface location of the hydrophilic c/e1-region within the core particle may alter following insertion of hydrophobic residues constituting the CTL epitopes, thereby compromising their presentation to the afferent immune system. Our data indicate that while the c/e1-region has a powerful adjuvanting effect for inserted B-epitopes, it does not serve this function for inserted CTL epitopes. These findings have generic implications for the development of CTL inducing vaccines using HBcAg as a vaccine vehicle.
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Affiliation(s)
- M Street
- Sir Albert Sakzewski Virus Research Centre, Royal Children's Hospital, Herston, Queensland, Australia
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Chatfield S, Roberts M, Londono P, Cropley I, Douce G, Dougan G. The development of oral vaccines based on live attenuated Salmonella strains. FEMS Immunol Med Microbiol 1993; 7:1-7. [PMID: 8364518 DOI: 10.1111/j.1574-695x.1993.tb00374.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Safe, live attenuated Salmonella strains can be produced by introducing defined non-reverting mutations into the chromosome. Such rationally attenuated strains have proved to be excellent oral vaccines in several animal species and can therefore be considered as candidate vaccines against invasive salmonellosis in both animals and man. A panel of attenuating lesions is now available from which it is possible to tailor the level of attenuation and hence produce strains with different immunogenic properties. Because of the spectrum of immune responses produced by such Salmonella vaccine strains they have been utilised extensively as vectors for delivering heterologous antigens to the mammalian immune system. We have focussed on the development of a single dose oral tetanus vaccine based on attenuated Salmonella strains expressing a non-toxic, immunogenic protein derived from tetanus toxin (fragment C). Several different expression systems have been used for fragment C and candidate vaccine strains have been constructed that are capable of protecting orally immunised mice against a lethal challenge with tetanus toxin. An oral tetanus vaccine may help to reduce the mortality rate from tetanus in the developing world by overcoming the problems associated with the implementation of vaccine programmes using the current parenteral vaccine.
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Affiliation(s)
- S Chatfield
- Department of Biochemistry, Imperial College of Science, Technology and Medicine, London, UK
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