1
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Costa B, Becker J, Krammer T, Mulenge F, Durán V, Pavlou A, Gern OL, Chu X, Li Y, Čičin-Šain L, Eiz-Vesper B, Messerle M, Dölken L, Saliba AE, Erhard F, Kalinke U. Human cytomegalovirus exploits STING signaling and counteracts IFN/ISG induction to facilitate infection of dendritic cells. Nat Commun 2024; 15:1745. [PMID: 38409141 PMCID: PMC10897438 DOI: 10.1038/s41467-024-45614-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 01/30/2024] [Indexed: 02/28/2024] Open
Abstract
Human cytomegalovirus (HCMV) is a widespread pathogen that in immunocompromised hosts can cause life-threatening disease. Studying HCMV-exposed monocyte-derived dendritic cells by single-cell RNA sequencing, we observe that most cells are entered by the virus, whereas less than 30% of them initiate viral gene expression. Increased viral gene expression is associated with activation of the stimulator of interferon genes (STING) that usually induces anti-viral interferon responses, and with the induction of several pro- (RHOB, HSP1A1, DNAJB1) and anti-viral (RNF213, TNFSF10, IFI16) genes. Upon progression of infection, interferon-beta but not interferon-lambda transcription is inhibited. Similarly, interferon-stimulated gene expression is initially induced and then shut off, thus further promoting productive infection. Monocyte-derived dendritic cells are composed of 3 subsets, with one being especially susceptible to HCMV. In conclusion, HCMV permissiveness of monocyte-derived dendritic cells depends on complex interactions between virus sensing, regulation of the interferon response, and viral gene expression.
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Grants
- 158989968 - SFB 900-B2 Deutsche Forschungsgemeinschaft (German Research Foundation)
- 398367752 - FOR 2830 Deutsche Forschungsgemeinschaft (German Research Foundation)
- EXC 2155 "RESIST" - Project ID 39087428 Deutsche Forschungsgemeinschaft (German Research Foundation)
- DO 1275/7-1 Deutsche Forschungsgemeinschaft (German Research Foundation)
- ER 927/2-1 - FOR2830 Deutsche Forschungsgemeinschaft (German Research Foundation)
- COALITION Niedersächsisches Ministerium für Wissenschaft und Kultur (Ministry for Science and Culture of Lower Saxony)
- Marie Skłodowska-Curie Actions Innovative Training Network (VIROINF: 955974) European Commission (EC)
- Marie Skłodowska-Curie Actions Innovative Training Network (VIROINF: 955974) European Commission (EC)
- 0703/68674/5/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
- 0703/89374/3/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
- 0703/68674/5/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
- 0703/89374/3/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
- 0703/68674/5/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
- 0703/89374/3/2017 Bayerisches Staatsministerium für Wirtschaft und Medien, Energie und Technologie (Bavarian Ministry of Economic Affairs and Media, Energy and Technology)
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Affiliation(s)
- Bibiana Costa
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Jennifer Becker
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Tobias Krammer
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz-Centre for Infection Research (HZI), Würzburg, Germany
| | - Felix Mulenge
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Verónica Durán
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Andreas Pavlou
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Olivia Luise Gern
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Xiaojing Chu
- Department of Computational Biology for Individualised Medicine, Centre for Individualised Infection Medicine (CiiM) & TWINCORE, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
| | - Yang Li
- Department of Computational Biology for Individualised Medicine, Centre for Individualised Infection Medicine (CiiM) & TWINCORE, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany
- Department of Internal Medicine and Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Luka Čičin-Šain
- Institute for Immune Aging and Chronic Infection, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Britta Eiz-Vesper
- Institute for Transfusion Medicine and Transplant Engineering, Hannover Medical School, Hannover, Germany
| | - Martin Messerle
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Lars Dölken
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany
| | - Antoine-Emmanuel Saliba
- Helmholtz Institute for RNA-based Infection Research (HIRI), Helmholtz-Centre for Infection Research (HZI), Würzburg, Germany
- University of Würzburg, Faculty of Medicine, Institute of Molecular Infection Biology (IMIB), Würzburg, Germany
| | - Florian Erhard
- Institute for Virology and Immunobiology, University of Würzburg, Würzburg, Germany.
- Faculty for Informatics and Data Science, University of Regensburg, Regensburg, Germany.
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, Hannover, Germany.
- Cluster of Excellence - Resolving Infection Susceptibility (RESIST, EXC 2155), Hannover Medical School, Hannover, Germany.
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2
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Myers Chen KV, de Groot AE, Mendez SA, Mallin MM, Amend SR, Pienta KJ. Targeting MerTK decreases efferocytosis and increases anti-tumor immune infiltrate in prostate cancer. Med Oncol 2023; 40:284. [PMID: 37644281 PMCID: PMC10465384 DOI: 10.1007/s12032-023-02153-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Accepted: 08/10/2023] [Indexed: 08/31/2023]
Abstract
The prostate cancer tumor microenvironment (TME) is comprised of many cell types that can contribute to and influence tumor progression. Some of the most abundant prostate cancer TME cells are macrophages, which can be modeled on a continuous spectrum of M1-like (anti-tumor macrophages) to M2-like (pro-tumor macrophages). A function of M2-like macrophages is efferocytosis, the phagocytosis of apoptotic cells. Based on literature from other models and contexts, efferocytosis further supports the M2-like macrophage phenotype. MerTK is a receptor tyrosine kinase that mediates efferocytosis by binding phosphatidylserine on apoptotic cells. We hypothesize efferocytosis in the prostate cancer TME is a tumor-promoting function of macrophages and that targeting MerTK-mediated efferocytosis will slow prostate cancer growth and promote an anti-tumor immune infiltrate. The aims of this study are to measure efferocytosis of prostate cancer cells by in vitro human M1/M2 macrophage models and assess changes in the M2-like, pro-tumor macrophage phenotype following prostate cancer efferocytosis. Additionally, this study aims to demonstrate that targeting MerTK decreases prostate cancer efferocytosis and promotes an anti-tumor immune infiltrate. We have developed methodology using flow cytometry to quantify efferocytosis of human prostate cancer cells using the LNCaP cell line. We observed that M2 macrophages efferocytose the LNCaP cell line more than M1 macrophages. Following efferocytosis of LNCaP cells by M2 human monocyte-derived macrophages (HMDMs), we observed an increase in the M2-like, pro-tumor phenotype by flow cytometry cell surface marker analysis. By qRT-PCR, flow cytometry, and Western blot, we detected greater MerTK expression in M2 than M1 macrophages. Targeting MerTK with antibody Mer590 decreased LNCaP efferocytosis by M2 HMDMs, establishing the role of MerTK in prostate cancer efferocytosis. In the prostate cancer mouse model hi-myc, Mertk KO increased anti-tumor immune infiltrate including CD8 T cells. These findings support targeting MerTK-mediated efferocytosis as a novel therapy for prostate cancer.
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Affiliation(s)
- Kayla V Myers Chen
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA.
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| | - Amber E de Groot
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Sabrina A Mendez
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA
| | - Mikaela M Mallin
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA
| | - Sarah R Amend
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA
- Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Kenneth J Pienta
- Cancer Ecology Center, The Brady Urological Institute, Johns Hopkins School of Medicine, 600 N. Wolfe St., Marburg Building Room 113, Baltimore, MD, 21287, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins School of Medicine, Baltimore, MD, USA
- Department of Oncology, Johns Hopkins School of Medicine, Baltimore, MD, USA
- Department of Chemical and Biomolecular Engineering, Johns Hopkins Whiting School of Engineering, Baltimore, MD, USA
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3
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Mao QY, He SY, Hu QY, Lu Y, Niu YX, Li XY, Zhang HM, Qin L, Su Q. Advanced Glycation End Products (AGEs) Inhibit Macrophage Efferocytosis of Apoptotic β Cells through Binding to the Receptor for AGEs. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:1204-1213. [PMID: 35173034 DOI: 10.4049/jimmunol.2100695] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 12/17/2021] [Indexed: 06/14/2023]
Abstract
Pancreatic β cell apoptosis is important in the pathogenesis of type 2 diabetes mellitus (T2DM). Generally, apoptotic β cells are phagocytosed by macrophages in a process known as "efferocytosis." Efferocytosis is critical to the resolution of inflammation and is impaired in T2DM. Advanced glycation end products (AGEs), which are increased in T2DM, are known to suppress phagocytosis function in macrophages. In this study, we found that AGEs inhibited efferocytosis of apoptotic β cells by primary peritoneal macrophages in C57BL/6J mice or mouse macrophage cell line Raw264.7. Mechanistically, AGEs inhibit efferocytosis by blocking Ras-related C3 botulinum toxin substrate 1 activity and cytoskeletal rearrangement through receptor for advanced glycation end products/ras homolog family member A/Rho kinase signaling in macrophages. Furthermore, it was observed that AGEs decreased the secretion of anti-inflammatory factors and promoted the proinflammatory ones to modulate the inflammation function of efferocytosis. Taken together, our results indicate that AGEs inhibit efferocytosis through binding to receptor for advanced glycation end products and activating ras homolog family member A/Rho kinase signaling, thereby inhibiting the anti-inflammatory function of efferocytosis.
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Affiliation(s)
- Qian-Yun Mao
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Sun-Yue He
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Qiu-Yue Hu
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Yao Lu
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Yi-Xin Niu
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Xiao-Yong Li
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Hong-Mei Zhang
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
| | - Li Qin
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
- Department of Endocrinology, Xinhua Hospital Chongming Branch, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Qing Su
- Department of Endocrinology, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China; and
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4
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Majai GE, Gogolák P, Tóth M, Hodrea J, Horváth D, Fésüs L, Rajnavölgyi É, Bácsi A. Autologous apoptotic neutrophils inhibit inflammatory cytokine secretion by human dendritic cells, but enhance Th1 responses. FEBS Open Bio 2020; 10:1492-1502. [PMID: 32473089 PMCID: PMC7396436 DOI: 10.1002/2211-5463.12904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 05/26/2020] [Indexed: 01/13/2023] Open
Abstract
Neutrophils represent the most abundant cell type in peripheral blood and exhibit a remarkably brief (6–8 h) half‐life in circulation. The fundamental role of these professional phagocytes has been established in acute inflammation, based on their potential to both initiate and receive inflammatory signals. Furthermore, neutrophils also take part in maintaining chronic inflammatory processes, such as in various autoimmune diseases. Here, we demonstrate that human autologous apoptotic neutrophils are readily engulfed by immature monocyte‐derived dendritic cells (moDCs) with similar efficiency as allogeneic apoptotic neutrophils [Majai G et al. (2010) J Leukoc Biol 88, 981–991]. Interestingly, in contrast to the allogeneic system, exposure of moDCs to autologous apoptotic neutrophils inhibits LPS + IFN‐γ‐induced production of inflammatory cytokines in a phagocytosis‐independent manner. Autologous apoptotic neutrophil‐primed DCs are able to modulate T‐cell responses by inducing the generation of IFN‐γ‐secreting cells while hampering that of IL‐17A‐producing cells. Our observations indicate that capture of autologous apoptotic neutrophils by immature DCs may impede further neutrophil‐mediated phagocytosis and tissue damage, and allow increased clearance of dying cells by macrophages.
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Affiliation(s)
- Gyöngyike Emese Majai
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Péter Gogolák
- Department of Immunology, Faculty of Medicine, University of Debrecen, Hungary
| | - Márta Tóth
- Department of Immunology, Faculty of Medicine, University of Debrecen, Hungary.,Doctoral School of Molecular Cellular and Immune Biology, University of Debrecen, Hungary
| | - Judit Hodrea
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Dorottya Horváth
- Department of Immunology, Faculty of Medicine, University of Debrecen, Hungary.,Doctoral School of Molecular Medicine, University of Debrecen, Hungary
| | - László Fésüs
- Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Debrecen, Hungary
| | - Éva Rajnavölgyi
- Department of Immunology, Faculty of Medicine, University of Debrecen, Hungary
| | - Attila Bácsi
- Department of Immunology, Faculty of Medicine, University of Debrecen, Hungary
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5
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Sordi R, Bet ÂC, Della Justina AM, Ramos GC, Assreuy J. The apoptosis clearance signal phosphatidylserine inhibits leukocyte migration and promotes inflammation resolution in vivo. Eur J Pharmacol 2020; 877:173095. [PMID: 32246923 DOI: 10.1016/j.ejphar.2020.173095] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/18/2020] [Accepted: 03/31/2020] [Indexed: 12/19/2022]
Abstract
Previous studies have shown that phagocytosis of apoptotic cells can tune the macrophage phenotype and trigger the resolution of inflammation. This mechanism is largely dependent on the recognition of phosphatidylserine (PS) residues on the outer membrane of dying cells. Therefore, we sought to assess the effects of PS-containing liposomes (mimics of apoptotic cells) on the leukocyte migration profile during the inflammatory process in vivo. Inflammation was induced by carrageenan injection into air pouches created on the dorsal region of mice, as this model enables convenient access to the exudates for further investigation. Mice were treated with PBS, PS-containing or phosphatidylcholine (PC)-containing liposomes (10, 30 or 100 mg/kg intraperitoneally [i.p.]). Starting 8 h after carrageenan injection, the level of leukocyte infiltration was monitored over three days. The PS-containing, but not PC-containing, liposomes reduced the polymorphonuclear (PMN) and mononuclear (MN) leukocyte influx into the inflamed pouches in a dose-dependent fashion. Most notably, these effects could also be adoptively transferred; that is, they were also found in mice injected with a liposome-free peritoneal lavage obtained from the mice that had received the intraperitoneal PS-liposome treatment. The effect of treatment with the PS-induced soluble mediators (PS-ISMs) was found to be dependent on the presence of peritoneal macrophages and was susceptible to heat, trypsin degradation, and cycloheximide treatment. The PS-containing liposomes promoted the reduction of PMN leukocyte influx by triggering the release of anti-inflammatory autacoids with a proteinaceous nature that were produced de novo after PS exposure.
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Affiliation(s)
- Regina Sordi
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Ângela Cristina Bet
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Ana Maria Della Justina
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Gustavo Campos Ramos
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Jamil Assreuy
- Department of Pharmacology, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil.
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6
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Franklin C, Bruderek K, Schilling B, Brandau S. Chemoirradiated neutrophils and T cells differentially affect immune functions of APCs. J Leukoc Biol 2019; 106:481-493. [PMID: 31075186 DOI: 10.1002/jlb.5a0618-242r] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 04/02/2019] [Accepted: 04/18/2019] [Indexed: 01/08/2023] Open
Abstract
Extracorporeal photopheresis (ECP) is known as an immunomodulatory therapy with few side effects, which is mainly used in the treatment of cutaneous T cell lymphoma, graft-versus-host disease, and allograft rejection. During ECP, leukocytes are separated from whole blood by leukapheresis, subsequently chemoirradiated with 8-methoxypsoralen and UVA light, and re-infused into the patient. Although clinically effective, its mode of action has not been fully elucidated. In the present study, we analyzed the interaction of chemoirradiated neutrophils and CD3+ lymphocytes with APC in an in vitro model. We report that chemoirradiated CD3+ T cells induced increased expression of activation markers on dendritic cells (DC), macrophages, and monocytes. Coculture of chemoirradiated CD3+ T cells with these APC also led to significantly increased secretion of TNF-α. Although less pronounced, additional activation of APC took place when APC were stimulated with LPS or IFN-γ. In contrast, chemoirradiated neutrophils did not show activating effects on APC. The presence of chemoirradiated neutrophils during LPS and IFN-γ stimulation of DC rather diminished DC and macrophage activation. In line with these findings DC cocultured with chemoirradiated CD3+ T cells, but not neutrophils, showed significantly increased activation of CD3+ responder lymphocytes in a mixed lymphocyte reaction. With this study, we demonstrate that chemoirradiated leukocytes have differential indirect immunomodulatory effects. Whereas chemoirradiated CD3+ T cells activate APC, chemoirradiated neutrophils suppress activation of APC in the presence of other activating factors, suggesting that the composition of the ECP-treated buffy coat might be of importance for its immunomodulatory effects.
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Affiliation(s)
- Cindy Franklin
- Department of Dermatology, Venereology and Allergology, University Hospital Essen, Essen, Germany.,Research Division, Department of Otorhinolaryngology, University Hospital Essen, Essen, Germany.,Department of Dermatology and Venereology, University Hospital of Cologne, Cologne, Germany
| | - Kirsten Bruderek
- Research Division, Department of Otorhinolaryngology, University Hospital Essen, Essen, Germany
| | - Bastian Schilling
- Department of Dermatology, Venereology and Allergology, University Hospital Essen, Essen, Germany.,Department of Dermatology, Venereology and Allergology, University Hospital Würzburg, Würzburg, Germany
| | - Sven Brandau
- Department of Dermatology, Venereology and Allergology, University Hospital Essen, Essen, Germany.,German Cancer Consortium (DKTK) Partner Site, Essen-Düsseldorf, Essen, Germany
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7
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Abstract
The engulfment of apoptotic cells by phagocytes, a process referred to as efferocytosis, is essential for maintenance of normal tissue homeostasis and a prerequisite for the resolution of inflammation. Neutrophils are the predominant circulating white blood cell in humans, and contain an arsenal of toxic substances that kill and degrade microbes. Neutrophils are short-lived and spontaneously die by apoptosis. This review will highlight how the engulfment of apoptotic neutrophils by human phagocytes occurs, how heterogeneity of phagocyte populations influences efferocytosis signaling, and downstream consequences of efferocytosis. The efferocytosis of apoptotic neutrophils by macrophages promotes anti-inflammatory signaling, prevents neutrophil lysis, and dampens immune responses. Given the immunomodulatory properties of efferocytosis, understanding pathways that regulate and enhance efferocytosis could be harnessed to combat infection and chronic inflammatory conditions.
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Affiliation(s)
- Mallary C Greenlee-Wacker
- Inflammation Program, Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine University of Iowa, Veterans Administration Medical Center, Iowa City, IA, USA
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8
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Bene K, Varga Z, Petrov VO, Boyko N, Rajnavolgyi E. Gut Microbiota Species Can Provoke both Inflammatory and Tolerogenic Immune Responses in Human Dendritic Cells Mediated by Retinoic Acid Receptor Alpha Ligation. Front Immunol 2017; 8:427. [PMID: 28458670 PMCID: PMC5394128 DOI: 10.3389/fimmu.2017.00427] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 03/27/2017] [Indexed: 12/18/2022] Open
Abstract
Dendritic cells are considered as the main coordinators of both mucosal and systemic immune responses, thus playing a determining role in shaping the outcome of effector cell responses. However, it is still uncovered how primary human monocyte-derived DC (moDC) populations drive the polarization of helper T (Th) cells in the presence of commensal bacteria harboring unique immunomodulatory properties. Furthermore, the individual members of the gut microbiota have the potential to modulate the outcome of immune responses and shape the immunogenicity of differentiating moDCs via the activation of retinoic acid receptor alpha (RARα). Here, we report that moDCs are able to mediate robust Th1 and Th17 responses upon stimulation by Escherichia coli Schaedler or Morganella morganii, while the probiotic Bacillus subtilis strain limits this effect. Moreover, physiological concentrations of all-trans retinoic acid (ATRA) are able to re-program the differentiation of moDCs resulting in altered gene expression profiles of the master transcription factors RARα and interferon regulatory factor 4, and concomitantly regulate the cell surface expression levels of CD1 proteins and also the mucosa-associated CD103 integrin to different directions. It was also demonstrated that the ATRA-conditioned moDCs exhibited enhanced pro-inflammatory cytokine secretion while reduced their co-stimulatory and antigen-presenting capacity thus reducing Th1 and presenting undetectable Th17 type responses against the tested microbiota strains. Importantly, these regulatory circuits could be prevented by the selective inhibition of RARα functionality. These results altogether demonstrate that selected commensal bacterial strains are able to drive strong effector immune responses by moDCs, while in the presence of ATRA, they support the development of both tolerogenic and inflammatory moDC in a RARα-dependent manner.
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Affiliation(s)
- Krisztian Bene
- Faculty of Medicine, Department of Immunology, University of Debrecen, Debrecen, Hungary
| | - Zsofia Varga
- Faculty of Medicine, Department of Immunology, University of Debrecen, Debrecen, Hungary
| | - Viktor O Petrov
- Faculty of Medicine, R&D Centre of Molecular Microbiology and Mucosal Immunology, Uzhhorod National University, Uzhhorod, Ukraine
| | - Nadiya Boyko
- Faculty of Medicine, R&D Centre of Molecular Microbiology and Mucosal Immunology, Uzhhorod National University, Uzhhorod, Ukraine
| | - Eva Rajnavolgyi
- Faculty of Medicine, Department of Immunology, University of Debrecen, Debrecen, Hungary
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9
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PPAR-γ agonist pioglitazone regulates dendritic cells immunogenicity mediated by DC-SIGN via the MAPK and NF-κB pathways. Int Immunopharmacol 2016; 41:24-34. [PMID: 27792919 DOI: 10.1016/j.intimp.2016.09.028] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 09/07/2016] [Accepted: 09/27/2016] [Indexed: 12/20/2022]
Abstract
Dendritic cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) is a dendritic cell-specific lectin which participates in dendritic cell (DC) trafficking, antigen uptake and DC-T cell interactions at the initiation of immune responses. This study investigated whether peroxisome proliferator-activated receptor-gamma (PPAR-γ) activation in human DCs regulates the immunogenicity of DCs mediated by DC-SIGN and exploited the possible molecular mechanisms, especially focused on the signaling pathways of mitogen-activated protein kinases (MAPK) and nuclear factor-κB (NF-κB). Here, we show that the PPAR-γ agonist pioglitazone decreased DC adhesion and transmigration, and DC stimulation of T cell proliferation mediated by DC-SIGN dependent on activation of PPAR-γ, although it increased DC endocytosis independent of PPAR-γ activation. Furthermore, PPAR-γ activation by pioglitazone in DCs down-regulated the expression of DC-SIGN, which was mediated by modulating the balance of the signaling pathways of extracellular signal-regulated kinase, c-Jun N-terminal kinase and NF-κB, but not p38 MAPK. Therefore, we conclude that PPAR-γ activation in human DCs regulates the immunogenicity of DCs mediated by DC-SIGN via the pathways of MAPK and NF-κB. These findings may support the important role of these mediators in the regulation of DC-mediated inflammatory and immunologic processes.
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10
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Zizzo G, Cohen PL. The PPAR-γ antagonist GW9662 elicits differentiation of M2c-like cells and upregulation of the MerTK/Gas6 axis: a key role for PPAR-γ in human macrophage polarization. JOURNAL OF INFLAMMATION-LONDON 2015; 12:36. [PMID: 25972766 PMCID: PMC4429687 DOI: 10.1186/s12950-015-0081-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/24/2015] [Indexed: 11/10/2022]
Abstract
Background The nuclear receptors PPAR-γ and LXRs regulate macrophage lipid metabolism and macrophage mediated inflammation. We examined the influence of these molecules on macrophage alternative activation, with particular focus on differentiation of “M2c” anti-inflammatory cells. Methods We cultured human monocytes in M0, M1, M2a or M2c macrophage differentiating conditions, in the presence or absence of PPAR-γ and LXR ligands. Flow cytometry was used to analyze membrane expression of phenotypic markers. Basal and LPS-stimulated production of soluble mediators was measured by ELISA. Efferocytosis assays were performed by coincubating monocytes/macrophages with apoptotic neutrophils. Results We found that PPAR-γ inhibition, using the PPAR-γ antagonist GW9662, elicits differentiation of M2c-like (CD206+ CD163+ CD16+) cells and upregulation of the MerTK/Gas6 axis. Exposure of differentiating macrophages to IFN-γ, GM-CSF or LPS (M1 conditions), however, hampers GW9662 induction of MerTK and Gas6. When macrophages are differentiated with IL-4 (M2a conditions), addition of GW9662 results into an M2a (CD206+ CD209+ CD163− MerTK−) to M2c (CD206high CD209− CD163+ MerTK+) polarization shift. Conversely, in the presence of dexamethasone (M2c conditions), the PPAR-γ agonist rosiglitazone attenuates CD163 and MerTK upregulation. The LXR agonist T0901317 induces MerTK independently of M2c polarization; indeed, CD206, CD163 and CD16 are downregulated. GW9662-differentiated M2c-like cells secrete high levels of Gas6 and low amounts of TNF-α and IL-10, mimicking dexamethasone effects in vitro. However, unlike conventional M2c cells, GW9662-differentiated cells do not show enhanced efferocytic ability. Conclusions Our results provide new insights into the role of PPAR-γ and LXR receptors in human macrophage activation and reveal the existence of different patterns regulating MerTK expression. Unexpectedly, PPAR-γ appears to negatively control the expansion of a discrete subset of M2c-like anti-inflammatory macrophages.
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Affiliation(s)
- Gaetano Zizzo
- Temple Autoimmunity Center, Temple University, 3500 N. Broad Street, 19140 Philadelphia, PA USA ; Department of Medicine, Section of Rheumatology, Temple University, 3322 N. Broad Street, 19140 Philadelphia, PA USA
| | - Philip L Cohen
- Temple Autoimmunity Center, Temple University, 3500 N. Broad Street, 19140 Philadelphia, PA USA ; Department of Medicine, Section of Rheumatology, Temple University, 3322 N. Broad Street, 19140 Philadelphia, PA USA
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11
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Zhang X, Ulm A, Somineni HK, Oh S, Weirauch MT, Zhang HX, Chen X, Lehn MA, Janssen EM, Ji H. DNA methylation dynamics during ex vivo differentiation and maturation of human dendritic cells. Epigenetics Chromatin 2014; 7:21. [PMID: 25161698 PMCID: PMC4144987 DOI: 10.1186/1756-8935-7-21] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 07/29/2014] [Indexed: 12/31/2022] Open
Abstract
Background Dendritic cells (DCs) are important mediators of innate and adaptive immune responses, but the gene networks governing their lineage differentiation and maturation are poorly understood. To gain insight into the mechanisms that promote human DC differentiation and contribute to the acquisition of their functional phenotypes, we performed genome-wide base-resolution mapping of 5-methylcytosine in purified monocytes and in monocyte-derived immature and mature DCs. Results DC development and maturation were associated with a great loss of DNA methylation across many regions, most of which occurs at predicted enhancers and binding sites for known transcription factors affiliated with DC lineage specification and response to immune stimuli. In addition, we discovered novel genes that may contribute to DC differentiation and maturation. Interestingly, many genes close to demethylated CG sites were upregulated in expression. We observed dynamic changes in the expression of TET2, DNMT1, DNMT3A and DNMT3B coupled with temporal locus-specific demethylation, providing possible mechanisms accounting for the dramatic loss in DNA methylation. Conclusions Our study is the first to map DNA methylation changes during human DC differentiation and maturation in purified cell populations and will greatly enhance the understanding of DC development and maturation and aid in the development of more efficacious DC-based therapeutic strategies.
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Affiliation(s)
- Xue Zhang
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Ashley Ulm
- Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Hari K Somineni
- Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Sunghee Oh
- Division of Human Genetics, Kim Sook Za Children's Hospital Medical Center Research Foundation, 745 JikJi Daero Heung Deok Gu, Cheongju, Chung Buk 361-841, South Korea
| | - Matthew T Weirauch
- Center for Autoimmune Genomics and Etiology and Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Hong-Xuan Zhang
- Procter & Gamble Co., Mason Business Center, 8700 S Mason Montgomery Road, Mason, OH 45040, USA
| | - Xiaoting Chen
- School of Electronic and Computing Systems, University of Cincinnati, Cincinnati, Ohio 45221, USA
| | - Maria A Lehn
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Edith M Janssen
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
| | - Hong Ji
- Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA
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12
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Lichtenstein RG, Rabinovich GA. Glycobiology of cell death: when glycans and lectins govern cell fate. Cell Death Differ 2013; 20:976-86. [PMID: 23703323 DOI: 10.1038/cdd.2013.50] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 04/08/2013] [Accepted: 04/16/2013] [Indexed: 02/04/2023] Open
Abstract
Although one typically thinks of carbohydrates as associated with cell growth and viability, glycosylation also has an integral role in many processes leading to cell death. Glycans, either alone or complexed with glycan-binding proteins, can deliver intracellular signals or control extracellular processes that promote initiation, execution and resolution of cell death programs. Herein, we review the role of glycans and glycan-binding proteins as essential components of the cell death machinery during physiologic and pathologic settings.
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Affiliation(s)
- R G Lichtenstein
- Avram and Stella Goren-Goldstein, Department of Biotechnology Engineering, Faculty of Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel
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13
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Anti- and Protumorigenic Effects of PPARγ in Lung Cancer Progression: A Double-Edged Sword. PPAR Res 2012; 2012:362085. [PMID: 22934105 PMCID: PMC3425863 DOI: 10.1155/2012/362085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 07/09/2012] [Indexed: 12/29/2022] Open
Abstract
Peroxisome proliferator-activated receptor-γ (PPARγ) is a member of the nuclear receptor superfamily of ligand-activated transcription factors that plays an important role in the control of gene expression linked to a variety of physiological processes, including cancer. Ligands for PPARγ include naturally occurring fatty acids and the thiazolidinedione class of antidiabetic drugs. Activation of PPARγ in a variety of cancer cells leads to inhibition of growth, decreased invasiveness, reduced production of proinflammatory cytokines, and promotion of a more differentiated phenotype. However, systemic activation of PPARγ has been reported to be protumorigenic in some in vitro systems and in vivo models. Here, we review the available data that implicate PPARγ in lung carcinogenesis and highlight the challenges of targeting PPARγ in lung cancer treatments.
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14
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Rethi B, Eidsmo L. FasL and TRAIL signaling in the skin during cutaneous leishmaniasis - implications for tissue immunopathology and infectious control. Front Immunol 2012; 3:163. [PMID: 22723798 PMCID: PMC3377931 DOI: 10.3389/fimmu.2012.00163] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Accepted: 05/31/2012] [Indexed: 01/09/2023] Open
Abstract
Cutaneous leishmaniasis (CL) is associated with chronic inflammation and ulceration of the skin. Tissue macrophages serve as host cells and immune activation is necessary for parasite clearance. The balance between immune-mediated tissue destruction and successful clearance of infection is delicate and ulceration has been proposed to be a result of infiltration of activated immune cells into the skin. FasL and TRAIL play a dual role in skin homeostasis through induction of apoptosis as well as proinflammatory signaling. During leishmaniasis, dysregulation of both FasL and TRAIL has been described by us and others but the resulting pathogenic effects in the skin during human leishmaniasis are not fully elucidated. Targeting disease specific immune deviations has proven to be a promising new approach for the therapy of autoimmune diseases. Potentially, targeting FasL or TRAIL in combination with microcidals could offer a future treatment strategy to reduce the disfiguring immunopathology associated with CL. In this mini review we will discuss how FasL and TRAIL-induced signaling may influence on the extent of tissue inflammation and the efficacy of parasite clearance in leishmaniasis.
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Affiliation(s)
- Bence Rethi
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
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15
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Szabo A, Bene K, Gogolák P, Réthi B, Lányi Á, Jankovich I, Dezső B, Rajnavölgyi E. RLR-mediated production of interferon-β by a human dendritic cell subset and its role in virus-specific immunity. J Leukoc Biol 2012; 92:159-69. [PMID: 22517920 DOI: 10.1189/jlb.0711360] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Cytosolic RIG-I-like helicases (RLR) are PRRs involved in type I IFN production and antiviral immunity. This study focuses to the comparison of the expression, function, and signaling cascades associated to RLR in the previously identified CD14(-)DC-SIGN(+)PPARγ(low)CD1a(+) and CD14(low)DC-SIGN(+)PPARγ(high)CD1a(-) human moDC subsets. Our results revealed that the expression of RLR genes and proteins as well as the activity of the coupled signaling pathways are significantly higher in the CD1a(+) subset than in its phenotypically and functionally distinct counterpart. Specific activation of RLR in moDCs by poly(I:C) or influenza virus was shown to induce the secretion of IFN-β via IRF3, whereas induction of proinflammatory cytokine responses were predominantly controlled by TLR3. The requirement of RLR-mediated signaling in CD1a(+) moDCs for priming naïve CD8(+) T lymphocytes and inducing influenza virus-specific cellular immune responses was confirmed by RIG-I/MDA5 silencing, which abrogated these functions. Our results demonstrate the subset-specific activation of RLR and the underlying mechanisms behind its cytokine secretion profile and identify CD1a(+) moDCs as an inflammatory subset with specialized functional activities. We also provide evidence that this migratory DC subset can be detected in human tonsil and reactive LNs.
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Affiliation(s)
- Attila Szabo
- Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen, Hungary
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16
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Dekkers JF, van der Ent CK, Kalkhoven E, Beekman JM. PPARγ as a therapeutic target in cystic fibrosis. Trends Mol Med 2012; 18:283-91. [PMID: 22494945 DOI: 10.1016/j.molmed.2012.03.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 03/06/2012] [Accepted: 03/12/2012] [Indexed: 12/31/2022]
Abstract
Cystic fibrosis (CF) is characterized by a proinflammatory pulmonary condition that may result from increased infections and altered intracellular metabolism in CFTR-deficient cells. The lipid-activated transcription factor peroxisome proliferator-activated receptor-γ (PPARγ) has well-established roles in immune cell function and inflammatory modulation and has been demonstrated to play an important role in the heightened inflammatory response in CF cells. Here, we summarize current literature describing PPARγ-dependent alterations of CF cells and discuss the potential of PPARγ ligands for treating CF.
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Affiliation(s)
- Johanna F Dekkers
- Department of Pediatric Pulmonology, University Medical Center Utrecht, Utrecht, The Netherlands
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17
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Han CZ, Ravichandran KS. Metabolic connections during apoptotic cell engulfment. Cell 2012; 147:1442-5. [PMID: 22196723 DOI: 10.1016/j.cell.2011.12.006] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Indexed: 01/22/2023]
Abstract
Billions of cells die via apoptosis every day and are swiftly removed. When a phagocyte engulfs an apoptotic cell, it essentially doubles its cellular contents, raising the question of how a phagocyte may manage the excess metabolic load. This Minireview discusses phagocyte cellular metabolism, the digestion of the ingested apoptotic cell, and the impact of these processes on engulfment.
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Affiliation(s)
- Claudia Z Han
- Department of Microbiology, Immunology, and Cancer Biology, Carter Immunology Center and the Center for Cell Clearance, University of Virginia, Charlottesville, VA 22908, USA
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18
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Hodrea J, Majai G, Doró Z, Zahuczky G, Pap A, Rajnavölgyi É, Fésüs L. The glucocorticoid dexamethasone programs human dendritic cells for enhanced phagocytosis of apoptotic neutrophils and inflammatory response. J Leukoc Biol 2011; 91:127-36. [PMID: 22028334 DOI: 10.1189/jlb.0511243] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
GCs are powerful anti-inflammatory compounds inhibiting inflammatory cell recruitment and production of proinflammatory cytokines. We have recently found that DCs, the key players of T cell priming and polarization, respond to allogeneic apoptotic neutrophils with proinflammatory cytokine release and Th1 cell activation. Here, we show that monocyte-derived human DCs develop their capacity to engulf apoptotic cells by up-regulating a set of apoptophagocytic genes. This gene expression pattern was reprogrammed when differentiation took place in the presence of the synthetic GC Dex, which increased the expression of phagocytosis receptors MERTK and CD14, the bridging molecule C1QA, DNASE2, and ADORA3. The increased phagocytosis was attenuated by the addition of ADORA3 antagonist and could not be observed when bone marrow-derived DCs of ADORA3 KO mice were treated with Dex. The GC-treated human DCs loaded with allogeneic apoptotic neutrophils secreted, in response to LPS and IFN-γ, the inflammatory cytokine TNF-α. Furthermore, the Dex-treated DCs could activate autologous T lymphocytes toward Th1 effector cells, and this was enhanced by their exposure to allogeneic apoptotic neutrophils.
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Affiliation(s)
- Judit Hodrea
- Department of Biochemistry and Molecular Biology, Signaling and Apoptosis and Genomics Research Group of the Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
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A-González N, Castrillo A. Liver X receptors as regulators of macrophage inflammatory and metabolic pathways. Biochim Biophys Acta Mol Basis Dis 2010; 1812:982-94. [PMID: 21193033 DOI: 10.1016/j.bbadis.2010.12.015] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/14/2010] [Accepted: 12/17/2010] [Indexed: 12/30/2022]
Abstract
The liver X receptors (LXRα and LXRβ) are members of the nuclear receptor family of transcription factors that play essential roles in the transcriptional control of lipid metabolism. LXRs are endogenously activated by modified forms of cholesterol known as oxysterols and control the expression of genes important for cholesterol uptake, efflux, transport, and excretion in multiple tissues. In addition to their role as cholesterol sensors, a number of studies have implicated LXRs in the modulation of innate and adaptive immune responses. Both through activation and repression mechanisms, LXRs regulate diverse aspects of inflammatory gene expression in macrophages. The ability of LXRs to coordinate metabolic and immune responses constitutes an attractive therapeutic target for the treatment of chronic inflammatory disorders. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease.
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Affiliation(s)
- Noelia A-González
- Department of Biochemistry and Molecular Biology, Universidad de Las Palmas de Gran Canaria, ULPGC, Las Palmas, Spain
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