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Redente EF, Kopf KW, Bahadur AN, Robichaud A, Lundblad LK, McDonald LT. Application-specific approaches to MicroCT for evaluation of mouse models of pulmonary disease. PLoS One 2023; 18:e0281452. [PMID: 36757935 PMCID: PMC9910664 DOI: 10.1371/journal.pone.0281452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 01/23/2023] [Indexed: 02/10/2023] Open
Abstract
The advent of micro-computed tomography (microCT) has provided significant advancement in our ability to generate clinically relevant assessments of lung health and disease in small animal models. As microCT use to generate outcomes analysis in pulmonary preclinical models has increased there have been substantial improvements in image quality and resolution, and data analysis software. However, there are limited published methods for standardized imaging and automated analysis available for investigators. Manual quantitative analysis of microCT images is complicated by the presence of inflammation and parenchymal disease. To improve the efficiency and limit user-associated bias, we have developed an automated pulmonary air and tissue segmentation (PATS) task list to segment lung air volume and lung tissue volume for quantitative analysis. We demonstrate the effective use of the PATS task list using four distinct methods for imaging, 1) in vivo respiration controlled scanning using a flexiVent, 2) longitudinal breath-gated in vivo scanning in resolving and non-resolving pulmonary disease initiated by lipopolysaccharide-, bleomycin-, and silica-exposure, 3) post-mortem imaging, and 4) ex vivo high-resolution scanning. The accuracy of the PATS task list was compared to manual segmentation. The use of these imaging techniques and automated quantification methodology across multiple models of lung injury and fibrosis demonstrates the broad applicability and adaptability of microCT to various lung diseases and small animal models and presents a significant advance in efficiency and standardization of preclinical microCT imaging and analysis for the field of pulmonary research.
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Affiliation(s)
- Elizabeth F. Redente
- Department of Pediatrics, National Jewish Health, Denver, Colorado, United States of America
- Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States of America
- * E-mail:
| | - Katrina W. Kopf
- Department of Academic Affairs, National Jewish Health, Denver, Colorado, United States of America
| | - Ali N. Bahadur
- Bruker BioSpin Corporation, Billerica, Massachusetts, United States of America
| | | | | | - Lindsay T. McDonald
- Ralph H. Johnson VA Medical Center, Charleston, South Carolina, United States of America
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2
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Firouzi F, Echeagaray O, Esquer C, Gude NA, Sussman MA. 'Youthful' phenotype of c-Kit + cardiac fibroblasts. Cell Mol Life Sci 2022; 79:424. [PMID: 35841449 PMCID: PMC10544823 DOI: 10.1007/s00018-022-04449-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 06/04/2022] [Accepted: 06/24/2022] [Indexed: 01/10/2023]
Abstract
Cardiac fibroblast (CF) population heterogeneity and plasticity present a challenge for categorization of biological and functional properties. Distinct molecular markers and associated signaling pathways provide valuable insight for CF biology and interventional strategies to influence injury response and aging-associated remodeling. Receptor tyrosine kinase c-Kit mediates cell survival, proliferation, migration, and is activated by pathological injury. However, the biological significance of c-Kit within CF population has not been addressed. An inducible reporter mouse detects c-Kit promoter activation with Enhanced Green Fluorescent Protein (EGFP) expression in cardiac cells. Coincidence of EGFP and c-Kit with the DDR2 fibroblast marker was confirmed using flow cytometry and immunohistochemistry. Subsequently, CFs expressing DDR2 with or without c-Kit was isolated and characterized. A subset of DDR2+ CFs also express c-Kit with coincidence in ~ 8% of total cardiac interstitial cells (CICs). Aging is associated with decreased number of c-Kit expressing DDR2+ CFs, whereas pathological injury induces c-Kit and DDR2 as well as the frequency of coincident expression in CICs. scRNA-Seq profiling reveals the transcriptome of c-Kit expressing CFs as cells with transitional phenotype. Cultured cardiac DDR2+ fibroblasts that are c-Kit+ exhibit morphological and functional characteristics consistent with youthful phenotypes compared to c-Kit- cells. Mechanistically, c-Kit expression correlates with signaling implicated in proliferation and cell migration, including phospho-ERK and pro-caspase 3. The phenotype of c-kit+ on DDR2+ CFs correlates with multiple characteristics of 'youthful' cells. To our knowledge, this represents the first evaluation of c-Kit biology within DDR2+ CF population and provides a fundamental basis for future studies to influence myocardial biology, response to pathological injury and physiological aging.
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Affiliation(s)
- Fareheh Firouzi
- SDSU Integrated Regenerative Research Institute and Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA
| | - Oscar Echeagaray
- SDSU Integrated Regenerative Research Institute and Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA
| | - Carolina Esquer
- SDSU Integrated Regenerative Research Institute and Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA
| | - Natalie A Gude
- SDSU Integrated Regenerative Research Institute and Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA
| | - Mark A Sussman
- SDSU Integrated Regenerative Research Institute and Biology Department, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA.
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3
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Ma R, Xie X, Zhao L, Wu Y, Wang J. Discoidin domain receptors (DDRs): Potential implications in periodontitis. J Cell Physiol 2021; 237:189-198. [PMID: 34431091 DOI: 10.1002/jcp.30560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 08/01/2021] [Accepted: 08/09/2021] [Indexed: 02/05/2023]
Abstract
Periodontitis is a chronic inflammatory disease leading to the destruction of periodontal tissues associated with high prevalence and significant economic burden. As special collagen-binding tyrosine kinase receptors, the discoidin domain receptors (DDRs) can control cell migration, adhesion, proliferation, and extracellular matrix remodeling. DDRs are constitutively expressed and widely distributed in periodontal tissues which are rich in collagen. Ddr1/2 knockout mice showed significant periodontal defects including connective tissue destruction, alveolar bone loss, and even tooth loss. It has been demonstrated that bone homeostasis, inflammation, matrix metalloproteinases, and autophagy are crucial characteristics involved in the pathogenesis of periodontitis. Of note, DDRs have been reported to participate in the above pathophysiological processes, implicating the potential roles of DDRs in periodontitis. In this review article, we aim to illustrate the possible roles of DDRs in periodontitis in an attempt to explore their potential value as therapeutic targets for periodontitis.
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Affiliation(s)
- Rui Ma
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xudong Xie
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Lei Zhao
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yafei Wu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jun Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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4
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Harasymowicz NS, Rashidi N, Savadipour A, Wu CL, Tang R, Bramley J, Buchser W, Guilak F. Single-cell RNA sequencing reveals the induction of novel myeloid and myeloid-associated cell populations in visceral fat with long-term obesity. FASEB J 2021; 35:e21417. [PMID: 33566380 PMCID: PMC8743141 DOI: 10.1096/fj.202001970r] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 12/29/2020] [Accepted: 01/21/2021] [Indexed: 12/12/2022]
Abstract
Macrophages and other immune cells are important contributors to obesity-associated inflammation; however, the cellular identities of these specific populations remain unknown. In this study, we identified individual populations of myeloid cells found in mouse epididymal/visceral adipose tissue by single-cell RNA sequencing, immunofluorescence, and flow cytometry. Multiple canonical correlation analysis identified 11 unique myeloid and myeloid-associate cell populations. In obese mice, we detected an increased percentage of monocyte-derived pro-inflammatory cells expressing Cd9 and Trem2, as well as significantly decreased percentages of multiple cell populations, including tissue-resident cells expressing Lyve1, Mafb, and Mrc1. We have identified and validated a novel myeloid/macrophage population defined by Ly6a expression, exhibiting both myeloid and mesenchymal characteristics, which increased with obesity and showed high pro-fibrotic characteristics in vitro. Our mouse adipose tissue myeloid cell atlas provides an important resource to investigate obesity-associated inflammation and fibrosis.
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Affiliation(s)
- Natalia S. Harasymowicz
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Neda Rashidi
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Alireza Savadipour
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
| | - Chia-Lung Wu
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - Ruhang Tang
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
| | - John Bramley
- Department of Genetics, Washington University in St. Louis, St. Louis, MO, USA
| | - William Buchser
- Department of Genetics, Washington University in St. Louis, St. Louis, MO, USA
| | - Farshid Guilak
- Department of Orthopaedic Surgery, Washington University in St. Louis, St. Louis, MO, USA
- Shriners Hospitals for Children, St. Louis, MO, USA
- Center of Regenerative Medicine, Washington University in St. Louis, St. Louis, MO, USA
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO, USA
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McDonald LT. Healing after COVID-19: are survivors at risk for pulmonary fibrosis? Am J Physiol Lung Cell Mol Physiol 2021; 320:L257-L265. [PMID: 33355522 PMCID: PMC7900916 DOI: 10.1152/ajplung.00238.2020] [Citation(s) in RCA: 129] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 12/18/2020] [Accepted: 12/20/2020] [Indexed: 12/16/2022] Open
Abstract
The novel SARS-CoV-2 coronavirus, which is responsible for COVID-19 disease, was first reported in Wuhan, China, in December of 2019. The virus rapidly spread, and the World Health Organization declared a pandemic by March 2020. With millions of confirmed cases worldwide, there is growing concern and considerable debate regarding the potential for coronavirus infection to contribute to an appreciable burden of chronic respiratory symptoms or fibrotic disease among recovered individuals. Because the first case of COVID-19 was documented less than one year ago, data regarding long-term clinical outcomes are not yet available, and predictions for long-term outcome are speculative at best. However, due to the staggering number of cases and the severity of disease in many individuals, there is a critical need to consider the potential long-term implications of COVID-19. This review examines current basic and clinical data regarding fibrogenic mechanisms of viral injury in the context of SARS-CoV-2. Several intersecting mechanisms between coronavirus infection and fibrotic pathways are discussed to highlight factors and processes that may be targetable to improve patient outcome. Reports of post-infection sequelae from previous coronavirus outbreaks are presented toward the goal of improved recognition of potential contributing risk factors for fibrotic disease.
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Affiliation(s)
- Lindsay T McDonald
- Research Service, Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina
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6
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Dekoster K, Decaesteker T, Berghen N, Van den Broucke S, Jonckheere AC, Wouters J, Krouglov A, Lories R, De Langhe E, Hoet P, Verbeken E, Vanoirbeek J, Vande Velde G. Longitudinal micro-computed tomography-derived biomarkers quantify non-resolving lung fibrosis in a silicosis mouse model. Sci Rep 2020; 10:16181. [PMID: 32999350 PMCID: PMC7527558 DOI: 10.1038/s41598-020-73056-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/09/2020] [Indexed: 12/16/2022] Open
Abstract
In spite of many compounds identified as antifibrotic in preclinical studies, pulmonary fibrosis remains a life-threatening condition for which highly effective treatment is still lacking. Towards improving the success-rate of bench-to-bedside translation, we investigated in vivo µCT-derived biomarkers to repeatedly quantify experimental silica-induced pulmonary fibrosis and assessed clinically relevant readouts up to several months after silicosis induction. Mice were oropharyngeally instilled with crystalline silica or saline and longitudinally monitored with respiratory-gated-high-resolution µCT to evaluate disease onset and progress using scan-derived biomarkers. At weeks 1, 5, 9 and 15, we assessed lung function, inflammation and fibrosis in subsets of mice in a cross-sectional manner. Silica-instillation increased the non-aerated lung volume, corresponding to onset and progression of inflammatory and fibrotic processes not resolving with time. Moreover, total lung volume progressively increased with silicosis. The volume of healthy, aerated lung first dropped then increased, corresponding to an acute inflammatory response followed by recovery into lower elevated aerated lung volume. Imaging results were confirmed by a significantly decreased Tiffeneau index, increased neutrophilic inflammation, increased IL-13, MCP-1, MIP-2 and TNF-α concentration in bronchoalveolar lavage fluid, increased collagen content and fibrotic nodules. µCT-derived biomarkers enable longitudinal evaluation of early onset inflammation and non-resolving pulmonary fibrosis as well as lung volumes in a sensitive and non-invasive manner. This approach and model of non-resolving lung fibrosis provides quantitative assessment of disease progression and stabilization over weeks and months, essential towards evaluation of fibrotic disease burden and antifibrotic therapy evaluation in preclinical studies.
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Affiliation(s)
- Kaat Dekoster
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium
| | - Tatjana Decaesteker
- Department of Chronic Diseases, Metabolism and Ageing, Lab of Respiratory Diseases, KU Leuven, Leuven, Belgium
| | - Nathalie Berghen
- Department of Development and Regeneration, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium.,Division of Rheumatology, University Hospitals Leuven, Leuven, Belgium
| | - Sofie Van den Broucke
- Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven, Leuven, Belgium
| | - Anne-Charlotte Jonckheere
- Department of Microbiology, Immunology and Transplantation, Allergy and Clinical Immunology Research Group, KU Leuven, Leuven, Belgium
| | - Jens Wouters
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium
| | - Anton Krouglov
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium
| | - Rik Lories
- Department of Development and Regeneration, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium.,Division of Rheumatology, University Hospitals Leuven, Leuven, Belgium
| | - Ellen De Langhe
- Department of Development and Regeneration, Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium.,Division of Rheumatology, University Hospitals Leuven, Leuven, Belgium
| | - Peter Hoet
- Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven, Leuven, Belgium
| | - Erik Verbeken
- Department of Imaging and Pathology, Translational Cell and Tissue Research Unit, KU Leuven, Leuven, Belgium
| | - Jeroen Vanoirbeek
- Department of Public Health and Primary Care, Centre for Environment and Health, KU Leuven, Leuven, Belgium
| | - Greetje Vande Velde
- Department of Imaging and Pathology, Biomedical MRI/MoSAIC, KU Leuven, Leuven, Belgium.
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7
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O'Brien M, Baicu CF, Van Laer AO, Zhang Y, McDonald LT, LaRue AC, Zile MR, Bradshaw AD. Pressure overload generates a cardiac-specific profile of inflammatory mediators. Am J Physiol Heart Circ Physiol 2020; 319:H331-H340. [PMID: 32589444 DOI: 10.1152/ajpheart.00274.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mechanisms that contribute to myocardial fibrosis, particularly in response to left ventricular pressure overload (LVPO), remain poorly defined. To test the hypothesis that a myocardial-specific profile of secreted factors is produced in response to PO, levels of 44 factors implicated in immune cell recruitment and function were assessed in a murine model of cardiac hypertrophy and compared with levels produced in a model of pulmonary fibrosis (PF). Mice subjected to PO were assessed at 1 and 4 wk. Protein from plasma, LV, lungs, and kidneys were analyzed by specific protein array analysis in parallel with protein from mice subjected to silica-instilled PF. Of the 44 factors assessed, 13 proteins were elevated in 1-wk PO myocardium, whereas 18 proteins were found increased in fibrotic lung. Eight of those increased in 1-wk LVPO were not found to be increased in fibrotic lungs (CCL-11, CCL-12, CCL-17, CCL-19, CCL-21, CCL-22, IL-16, and VEGF). Additionally, six factors were increased in plasma of 1-wk LVPO in the absence of increases in myocardial levels. In contrast, in mice with PF, no factors were found increased in plasma that were not elevated in lung tissue. Of those factors increased at 1 wk, only TIMP-1 remained elevated at 4 wk of LVPO. Immunohistochemistry of myocardial vasculature at 1 and 4 wk revealed similar amounts of total vasculature; however, evidence of activated endothelium was observed at 1 wk and, to a lesser extent, at 4 wk LVPO. In conclusion, PO myocardium generated a unique signature of cytokine expression versus that of fibrotic lung.NEW & NOTEWORTHY Myocardial fibrosis and the resultant increases in myocardial stiffness represent pivotal consequences of chronic pressure overload (PO). In this study, cytokine profiles produced in a murine model of cardiac fibrosis induced by PO were compared with those produced in response to silica-induced lung fibrosis. A unique profile of cardiac tissue-specific and plasma-derived factors generated in response to PO are reported.
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Affiliation(s)
- Matthew O'Brien
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Catalin F Baicu
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - An O Van Laer
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Yuhua Zhang
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
| | - Lindsey T McDonald
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina.,Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina
| | - Amanda C LaRue
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina.,Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina
| | - Michael R Zile
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina.,Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina
| | - Amy D Bradshaw
- Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina.,Ralph H. Johnson Veterans Affairs Medical Center, Charleston, South Carolina
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Kumar A, Dutta Choudhury M, Ghosh P, Palit P. Discoidin domain receptor 2: An emerging pharmacological drug target for prospective therapy against osteoarthritis. Pharmacol Rep 2019; 71:399-408. [DOI: 10.1016/j.pharep.2019.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/27/2018] [Accepted: 01/14/2019] [Indexed: 11/30/2022]
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9
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High-Fat Diet Alters Immunogenic Properties of Circulating and Adipose Tissue-Associated Myeloid-Derived CD45 +DDR2 + Cells. Mediators Inflamm 2019; 2019:1648614. [PMID: 31015794 PMCID: PMC6421777 DOI: 10.1155/2019/1648614] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/04/2019] [Accepted: 01/15/2019] [Indexed: 12/26/2022] Open
Abstract
Chronic inflammation is evident in the adipose tissue and periphery of patients with obesity, as well as mouse models of obesity. T cell subsets in obese adipose tissue are skewed towards Th1- and Th17-associated phenotypes and their secreted cytokines contribute to obesity-associated inflammation. Our lab recently identified a novel, myeloid-derived CD45+DDR2+ cell subset that modulates T cell activity. The current study sought to determine how these myeloid-derived CD45+DDR2+ cells are altered in the adipose tissue and peripheral blood of preobese mice and how this population modulates T cell activity. C57BL/6 mice were fed with a diet high in milkfat (60%·kcal, HFD) ad libitum until a 20% increase in total body weight was reached, and myeloid-derived CD45+DDR2+ cells and CD4+ T cells in visceral adipose tissue (VAT), mammary gland-associated adipose tissue (MGAT), and peripheral blood (PB) were phenotypically analyzed. Also analyzed was whether mediators from MGAT-primed myeloid-derived CD45+DDR2+ cells stimulate normal CD4+ T cell cytokine production. A higher percentage of myeloid-derived CD45+DDR2+ cells expressed the activation markers MHC II and CD80 in both VAT and MGAT of preobese mice. CD4+ T cells were preferentially skewed towards Th1- and Th17-associated phenotypes in the adipose tissue and periphery of preobese mice. In vitro, MGAT from HFD-fed mice triggered myeloid-derived CD45+DDR2+ cells to induce CD4+ T cell IFN-γ and TNF-α production. Taken together, this study shows that myeloid-derived CD45+DDR2+ cells express markers of immune activation and suggests that they play an immune modulatory role in the adipose tissue of preobese mice.
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