1
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Congues F, Wang P, Lee J, Lin D, Shahid A, Xie J, Huang Y. Targeting aryl hydrocarbon receptor to prevent cancer in barrier organs. Biochem Pharmacol 2024; 223:116156. [PMID: 38518996 PMCID: PMC11144369 DOI: 10.1016/j.bcp.2024.116156] [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: 10/31/2023] [Revised: 03/08/2024] [Accepted: 03/19/2024] [Indexed: 03/24/2024]
Abstract
The skin, lung, and gut are important barrier organs that control how the body reacts to environmental stressors such as ultraviolet (UV) radiation, air pollutants, dietary components, and microorganisms. The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that plays an important role in maintaining homeostasis of barrier organs. AhR was initially discovered as a receptor for environmental chemical carcinogens such as polycyclic aromatic hydrocarbons (PAHs). Activation of AhR pathways by PAHs leads to increased DNA damage and mutations which ultimately lead to carcinogenesis. Ongoing evidence reveals an ever-expanding role of AhR. Recently, AhR has been linked to immune systems by the interaction with the development of natural killer (NK) cells, regulatory T (Treg) cells, and T helper 17 (Th17) cells, as well as the production of immunosuppressive cytokines. However, the role of AhR in carcinogenesis is not as straightforward as we initially thought. Although AhR activation has been shown to promote carcinogenesis in some studies, others suggest that it may act as a tumor suppressor. In this review, we aim to explore the role of AhR in the development of cancer that originates from barrier organs. We also examined the preclinical efficacy data of AhR agonists and antagonists on carcinogenesis to determine whether AhR modulation can be a viable option for cancer chemoprevention.
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Affiliation(s)
- Francoise Congues
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Pengcheng Wang
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA; Department of Stomatology, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Joshua Lee
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Daphne Lin
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Ayaz Shahid
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Jianming Xie
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA
| | - Ying Huang
- Department of Biotechnology and Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, Pomona, CA 91766, USA.
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2
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Healey AM, Fenner KN, O'Dell CT, Lawrence BP. Aryl hydrocarbon receptor activation alters immune cell populations in the lung and bone marrow during coronavirus infection. Am J Physiol Lung Cell Mol Physiol 2024; 326:L313-L329. [PMID: 38290163 PMCID: PMC11281796 DOI: 10.1152/ajplung.00236.2023] [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: 07/26/2023] [Revised: 01/11/2024] [Accepted: 01/11/2024] [Indexed: 02/01/2024] Open
Abstract
Respiratory viral infections are one of the major causes of illness and death worldwide. Symptoms associated with respiratory infections can range from mild to severe, and there is limited understanding of why there is large variation in severity. Environmental exposures are a potential causative factor. The aryl hydrocarbon receptor (AHR) is an environment-sensing molecule expressed in all immune cells. Although there is considerable evidence that AHR signaling influences immune responses to other immune challenges, including respiratory pathogens, less is known about the impact of AHR signaling on immune responses during coronavirus (CoV) infection. In this study, we report that AHR activation significantly altered immune cells in the lungs and bone marrow of mice infected with a mouse CoV. AHR activation transiently reduced the frequency of multiple cells in the mononuclear phagocyte system, including monocytes, interstitial macrophages, and dendritic cells in the lung. In the bone marrow, AHR activation altered myelopoiesis, as evidenced by a reduction in granulocyte-monocyte progenitor cells and an increased frequency of myeloid-biased progenitor cells. Moreover, AHR activation significantly affected multiple stages of the megakaryocyte lineage. Overall, these findings indicate that AHR activation modulates multiple aspects of the immune response to a CoV infection. Given the significant burden of respiratory viruses on human health, understanding how environmental exposures shape immune responses to infection advances our knowledge of factors that contribute to variability in disease severity and provides insight into novel approaches to prevent or treat disease.NEW & NOTEWORTHY Our study reveals a multifaceted role for aryl hydrocarbon receptor (AHR) signaling in the immune response to coronavirus (CoV) infection. Sustained AHR activation during in vivo mouse CoV infection altered the frequency of mature immune cells in the lung and modulated emergency hematopoiesis, specifically myelopoiesis and megakaryopoiesis, in bone marrow. This provides new insight into immunoregulation by the AHR and extends our understanding of how environmental exposures can impact host responses to respiratory viral infections.
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Affiliation(s)
- Alicia M Healey
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States
| | - Kristina N Fenner
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States
| | - Colleen T O'Dell
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States
| | - B Paige Lawrence
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States
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3
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Cerracchio C, Amoroso MG, Piccolo M, Ferraro MG, Nocera FP, De Martino L, Serra F, Irace C, Tenore GC, Novellino E, Santamaria R, Fiorito F. Antiviral activity of Taurisolo® during bovine alphaherpesvirus 1 infection. Virus Res 2023; 336:199217. [PMID: 37666327 PMCID: PMC10504091 DOI: 10.1016/j.virusres.2023.199217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 08/28/2023] [Accepted: 09/01/2023] [Indexed: 09/06/2023]
Abstract
Bovine alphaherpesvirus 1 (BoAHV-1), the pathogen causing Infectious Bovine Rhinotracheitis (IBR) and predisposing to polymicrobial infections in cattle, provokes farm economic losses and trading restrictions in the world. However, nontoxic antiviral agents for BoAHV-1 infection are still unavailable, but plant extracts, such as flavonoid derivatives possess activity against BoAHV-1. Taurisolo®, a nutraceutical produced by Aglianico grape pomace, has recently shown promising antiviral activity. Herein, the potential activity of Taurisolo® during BoAHV-1 infection in Madin Darby bovine kidney (MDBK) cells was tested. Taurisolo® enhanced cell viability and reduced morphological death signs in BoAHV-1-infected cells. Moreover, Taurisolo® influenced the expression of bICP0, the key regulatory protein of BoAHV-1, and it strongly diminished virus yield. These effects were associated with an up-regulation of aryl hydrocarbon receptor (AhR), a transcription factor involved in microbial metabolism and immune response. In conclusion, our findings indicate that Taurisolo® may represent a potential antiviral agent against BoAHV-1 infection. Noteworthy, AhR could be involved in the observed effects and become a new target in antiviral therapy.
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Affiliation(s)
- Claudia Cerracchio
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy
| | | | - Marialuisa Piccolo
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy
| | | | - Francesca Paola Nocera
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy
| | - Luisa De Martino
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy
| | - Francesco Serra
- Istituto Zooprofilattico del Mezzogiorno, 80055 Portici, Naples, Italy
| | - Carlo Irace
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy.
| | - Gian Carlo Tenore
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy
| | - Ettore Novellino
- Department of Medicine and Surgery, Catholic University of the Sacred Heart, 00168 Rome, Italy
| | - Rita Santamaria
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy
| | - Filomena Fiorito
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy.
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4
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Oljuskin T, Azodi N, Volpedo G, Bhattacharya P, Markle HL, Hamano S, Matlashewski G, Satoskar AR, Gannavaram S, Nakhasi HL. Leishmania major centrin knock-out parasites reprogram tryptophan metabolism to induce a pro-inflammatory response. iScience 2023; 26:107593. [PMID: 37744403 PMCID: PMC10517402 DOI: 10.1016/j.isci.2023.107593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 07/07/2023] [Accepted: 08/07/2023] [Indexed: 09/26/2023] Open
Abstract
Leishmaniasis is a parasitic disease that is prevalent in 90 countries, and yet no licensed human vaccine exists against it. Toward control of leishmaniasis, we have developed Leishmania major centrin gene deletion mutant strains (LmCen-/-) as a live attenuated vaccine, which induces a strong IFN-γ-mediated protection to the host. However, the immune mechanisms of such protection remain to be understood. Metabolomic reprogramming of the host cells following Leishmania infection has been shown to play a critical role in pathogenicity and shaping the immune response following infection. Here, we applied untargeted mass spectrometric analysis to study the metabolic changes induced by infection with LmCen-/- and compared those with virulent L. major parasite infection to identify the immune mechanism of protection. Our data show that immunization with LmCen-/- parasites, in contrast to virulent L. major infection promotes a pro-inflammatory response by utilizing tryptophan to produce melatonin and downregulate anti-inflammatory kynurenine-AhR and FICZ-AhR signaling.
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Affiliation(s)
- Timur Oljuskin
- Animal Parasitic Diseases Laboratory, Agricultural Research Service, USDA, Beltsville, MD 20705, USA
| | - Nazli Azodi
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD 20993, USA
| | - Greta Volpedo
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
| | - Parna Bhattacharya
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD 20993, USA
| | - Hannah L. Markle
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD 20993, USA
| | - Shinjiro Hamano
- Department of Parasitology, Institute of Tropical Medicine (NEKKEN), The Joint Usage/Research Center on Tropical Disease, Nagasaki University, Nagasaki, Japan
- Nagasaki University Graduate School of Biomedical Sciences Doctoral Leadership Program, Nagasaki, Japan
| | - Greg Matlashewski
- Department of Microbiology and Immunology, McGill University, Montreal, QC, Canada
| | - Abhay R. Satoskar
- Department of Microbiology, The Ohio State University, Columbus, OH 43210, USA
- Department of Pathology, Wexner Medical Center, The Ohio State University, Columbus, OH 43210, USA
| | - Sreenivas Gannavaram
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD 20993, USA
| | - Hira L. Nakhasi
- Division of Emerging and Transfusion Transmitted Diseases, CBER, FDA, Silver Spring, MD 20993, USA
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5
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Pelaez MA, Torti MF, Alvarez De Lauro AE, Marquez AB, Giovannoni F, Damonte EB, García CC. Modulation of the Aryl Hydrocarbon Receptor Signaling Pathway Impacts on Junín Virus Replication. Viruses 2023; 15:v15020369. [PMID: 36851583 PMCID: PMC9967227 DOI: 10.3390/v15020369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/17/2023] [Accepted: 01/20/2023] [Indexed: 01/31/2023] Open
Abstract
Junín virus (JUNV), a member of the family Arenaviridae, is the etiological agent of the Argentine hemorrhagic fever, an endemic disease in the rural region of Argentina lacking a specific chemotherapy. Aryl hydrocarbon receptor (AHR) is expressed in several mammalian tissues and has been indicated as a sensor of ligands from variable sources and a modulator of the cell immune response. Interestingly, recent studies have suggested that the activation or depression of the AHR signaling pathway may play a role in the outcome of diverse human viral infections. In the present report, the effect of the pharmacological modulation of AHR on JUNV in vitro infection was analyzed. An initial microarray screening showed that the AHR pathway was overexpressed in JUNV-infected hepatic cells. Concomitantly, the infection of Vero and Huh-7 cells with the JUNV strains IV4454 and Candid#1 was significantly inhibited in a dose-dependent manner by treatment with CH223191, a specific AHR antagonist, as detected by infectivity assays, real-time RT-PCR and immunofluorescence detection of viral proteins. Furthermore, the pro-viral role of AHR in JUNV infection appears to be independent of the IFN-I pathway. Our findings support the promising perspectives of the pharmacological modulation of AHR as a potential target for the control of AHF.
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Affiliation(s)
- Miguel Angel Pelaez
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
| | - María Florencia Torti
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
| | - Aaron Ezequiel Alvarez De Lauro
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
| | - Agostina Belén Marquez
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
| | - Federico Giovannoni
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Elsa Beatriz Damonte
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
- Correspondence: (E.B.D.); (C.C.G.)
| | - Cybele Carina García
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN, University of Buenos Aires/Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires 1428, Argentina
- Correspondence: (E.B.D.); (C.C.G.)
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6
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Targeting Aryl Hydrocarbon Receptor Signaling Enhances Type I Interferon-Independent Resistance to Herpes Simplex Virus. Microbiol Spectr 2021; 9:e0047321. [PMID: 34668726 PMCID: PMC8528105 DOI: 10.1128/spectrum.00473-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcript factor that plays an important role in regulating immunity and cell differentiation. However, its role in cell-autonomous antiviral resistance has not been fully elucidated. Here, we show that interruption of AHR signaling in human cells by a chemical antagonist or genetic targeting led to significant reductions in the replication of herpes simplex virus 1 (HSV-1) and cytomegalovirus (CMV), revealing an unexpected proviral function of AHR. Interestingly, the enhanced viral control in the absence of AHR is independent of type I interferon (IFN) signaling. Together, these results reveal a previously unknown function of AHR in promoting viral replication in vitro and suggest a potential intervention point for treating viral disease. IMPORTANCE This study describes how a virus might utilize host aryl hydrocarbon receptor signaling to promote its replication, even in the presence of type I interferons.
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7
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Larigot L, Benoit L, Koual M, Tomkiewicz C, Barouki R, Coumoul X. Aryl Hydrocarbon Receptor and Its Diverse Ligands and Functions: An Exposome Receptor. Annu Rev Pharmacol Toxicol 2021; 62:383-404. [PMID: 34499523 DOI: 10.1146/annurev-pharmtox-052220-115707] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a transcriptional factor that regulates multiple functions following its activation by a variety of ligands, including xenobiotics, natural products, microbiome metabolites, and endogenous molecules. Because of this diversity, the AhR constitutes an exposome receptor. One of its main functions is to regulate several lines of defense against chemical insults and bacterial infections. Indeed, in addition to its well-established detoxication function, it has several functions at physiological barriers, and it plays a critical role in immunomodulation. The AhR is also involved in the development of several organs and their homeostatic maintenance. Its activity depends on the type of ligand and on the time frame of the receptor activation, which can be either sustained or transient, leading in some cases to opposite modes of regulations as illustrated in the regulation of different cancer pathways. The development of selective modulators and their pharmacological characterization are important areas of research. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 62 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Lucie Larigot
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France;
| | - Louise Benoit
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France; .,Service de Chirurgie Cancérologique Gynécologique et du Sein, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou, 75015 Paris, France
| | - Meriem Koual
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France; .,Service de Chirurgie Cancérologique Gynécologique et du Sein, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou, 75015 Paris, France
| | - Céline Tomkiewicz
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France;
| | - Robert Barouki
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France; .,Service de Chirurgie Cancérologique Gynécologique et du Sein, Assistance Publique-Hôpitaux de Paris, Hôpital Européen Georges-Pompidou, 75015 Paris, France
| | - Xavier Coumoul
- INSERM UMR-S1124, T3S, Toxicologie Environnementale, Cibles thérapeutiques, Signalisation cellulaire et Biomarqueurs, and Université de Paris, 75006 Paris, France;
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8
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Torti MF, Giovannoni F, Quintana FJ, García CC. The Aryl Hydrocarbon Receptor as a Modulator of Anti-viral Immunity. Front Immunol 2021; 12:624293. [PMID: 33746961 PMCID: PMC7973006 DOI: 10.3389/fimmu.2021.624293] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 02/03/2021] [Indexed: 12/30/2022] Open
Abstract
The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor, which interacts with a wide range of organic molecules of endogenous and exogenous origin, including environmental pollutants, tryptophan metabolites, and microbial metabolites. The activation of AHR by these agonists drives its translocation into the nucleus where it controls the expression of a large number of target genes that include the AHR repressor (AHRR), detoxifying monooxygenases (CYP1A1 and CYP1B1), and cytokines. Recent advances reveal that AHR signaling modulates aspects of the intrinsic, innate and adaptive immune response to diverse microorganisms. This review will focus on the increasing evidence supporting a role for AHR as a modulator of the host response to viral infection.
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Affiliation(s)
- Maria Florencia Torti
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN-Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Federico Giovannoni
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Francisco Javier Quintana
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | - Cybele Carina García
- Laboratory of Antiviral Strategies, Biochemistry Department, School of Sciences, University of Buenos Aires, IQUIBICEN-Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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9
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Woodby B, Arnold MM, Valacchi G. SARS-CoV-2 infection, COVID-19 pathogenesis, and exposure to air pollution: What is the connection? Ann N Y Acad Sci 2021; 1486:15-38. [PMID: 33022781 PMCID: PMC7675684 DOI: 10.1111/nyas.14512] [Citation(s) in RCA: 101] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/11/2020] [Accepted: 09/21/2020] [Indexed: 12/20/2022]
Abstract
Exposure to air pollutants has been previously associated with respiratory viral infections, including influenza, measles, mumps, rhinovirus, and respiratory syncytial virus. Epidemiological studies have also suggested that air pollution exposure is associated with increased cases of SARS-CoV-2 infection and COVID-19-associated mortality, although the molecular mechanisms by which pollutant exposure affects viral infection and pathogenesis of COVID-19 remain unknown. In this review, we suggest potential molecular mechanisms that could account for this association. We have focused on the potential effect of exposure to nitrogen dioxide (NO2 ), ozone (O3 ), and particulate matter (PM) since there are studies investigating how exposure to these pollutants affects the life cycle of other viruses. We have concluded that pollutant exposure may affect different stages of the viral life cycle, including inhibition of mucociliary clearance, alteration of viral receptors and proteases required for entry, changes to antiviral interferon production and viral replication, changes in viral assembly mediated by autophagy, prevention of uptake by macrophages, and promotion of viral spread by increasing epithelial permeability. We believe that exposure to pollutants skews adaptive immune responses toward bacterial/allergic immune responses, as opposed to antiviral responses. Exposure to air pollutants could also predispose exposed populations toward developing COIVD-19-associated immunopathology, enhancing virus-induced tissue inflammation and damage.
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Affiliation(s)
- Brittany Woodby
- Animal Science DepartmentPlants for Human Health Institute, N.C. Research Campus, North Carolina State UniversityKannapolisNorth Carolina
| | - Michelle M. Arnold
- Department of Microbiology and ImmunologyCenter for Molecular and Tumor VirologyLouisiana State University Health Sciences CenterShreveportLouisiana
| | - Giuseppe Valacchi
- Animal Science DepartmentPlants for Human Health Institute, N.C. Research Campus, North Carolina State UniversityKannapolisNorth Carolina
- Department of Life Sciences and BiotechnologyUniversity of FerraraFerraraItaly
- Department of Food and NutritionKyung Hee UniversitySeoulSouth Korea
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10
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Gurczynski SJ, Pereira NL, Hrycaj SM, Wilke C, Zemans RL, Moore BB. Stem cell transplantation uncovers TDO-AHR regulation of lung dendritic cells in herpesvirus-induced pathology. JCI Insight 2021; 6:139965. [PMID: 33491663 PMCID: PMC7934859 DOI: 10.1172/jci.insight.139965] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 12/03/2020] [Indexed: 12/12/2022] Open
Abstract
The aryl-hydrocarbon receptor (AHR) is an intracellular sensor of aromatic hydrocarbons that sits at the top of various immunomodulatory pathways. Here, we present evidence that AHR plays a role in controlling IL-17 responses and the development of pulmonary fibrosis in response to respiratory pathogens following bone marrow transplant (BMT). Mice infected intranasally with gamma-herpesvirus 68 (γHV-68) following BMT displayed elevated levels of the AHR ligand, kynurenine (kyn), in comparison with control mice. Inhibition or genetic ablation of AHR signaling resulted in a significant decrease in IL-17 expression as well as a reduction in lung pathology. Lung CD103+ DCs expressed AHR following BMT, and treatment of induced CD103+ DCs with kyn resulted in altered cytokine production in response to γHV-68. Interestingly, mice deficient in the kyn-producing enzyme indolamine 2-3 dioxygenase showed no differences in cytokine responses to γHV-68 following BMT; however, isolated pulmonary fibroblasts infected with γHV-68 expressed the kyn-producing enzyme tryptophan dioxygenase (TDO2). Our data indicate that alterations in the production of AHR ligands in response to respiratory pathogens following BMT results in a pro-Th17 phenotype that drives lung pathology. We have further identified the TDO2/AHR axis as a potentially novel form of intercellular communication between fibroblasts and DCs that shapes immune responses to respiratory pathogens.
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Affiliation(s)
- Stephen J Gurczynski
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and
| | - Nicolas L Pereira
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and
| | - Steven M Hrycaj
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and
| | - Carol Wilke
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and
| | - Rachel L Zemans
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and
| | - Bethany B Moore
- Division of Pulmonary & Critical Care Medicine, Department of Internal Medicine, and.,Department of Microbiology and Immunology, University of Michigan, Ann Arbor, Michigan, USA
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11
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Potential role of polycyclic aromatic hydrocarbons in air pollution-induced non-malignant respiratory diseases. Respir Res 2020; 21:299. [PMID: 33187512 PMCID: PMC7666487 DOI: 10.1186/s12931-020-01563-1] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/01/2020] [Indexed: 12/12/2022] Open
Abstract
Epidemiological studies have found strong associations between air pollution and respiratory effects including development and/or exacerbation of asthma and chronic obstructive pulmonary disease (COPD) as well as increased occurrence of respiratory infections and lung cancer. It has become increasingly clear that also polycyclic aromatic hydrocarbons (PAHs) may affect processes linked to non-malignant diseases in the airways. The aim of the present paper was to review epidemiological studies on associations between gas phase and particle-bound PAHs in ambient air and non-malignant respiratory diseases or closely related physiological processes, to assess whether PAH-exposure may explain some of the effects associated with air pollution. Based on experimental in vivo and in vitro studies, we also explore possible mechanisms for how different PAHs may contribute to such events. Epidemiological studies show strongest evidence for an association between PAHs and asthma development and respiratory function in children. This is supported by studies on prenatal and postnatal exposure. Exposure to PAHs in adults seems to be linked to respiratory functions, exacerbation of asthma and increased morbidity/mortality of obstructive lung diseases. However, available studies are few and weak. Notably, the PAHs measured in plasma/urine also represent other exposure routes than inhalation. Furthermore, the role of PAHs measured in air is difficult to disentangle from that of other air pollution components originating from combustion processes. Experimental studies show that PAHs may trigger various processes linked to non-malignant respiratory diseases. Physiological- and pathological responses include redox imbalance, oxidative stress, inflammation both from the innate and adaptive immune systems, smooth muscle constriction, epithelial- and endothelial dysfunction and dysregulated lung development. Such biological responses may at the molecular level be initiated by PAH-binding to the aryl hydrocarbon receptor (AhR), but possibly also through interactions with beta-adrenergic receptors. In addition, reactive PAH metabolites or reactive oxygen species (ROS) may interfere directly with ion transporters and enzymes involved in signal transduction. Overall, the reviewed literature shows that respiratory effects of PAH-exposure in ambient air may extend beyond lung cancer. The relative importance of the specific PAHs ability to induce disease may differ between the biological endpoint in question.
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12
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Noakes R. Frontal Fibrosing Alopecia. An Example of Disrupted Aryl Hydrocarbon Receptor-Mediated Immunological Homeostasis in the Skin? Clin Cosmet Investig Dermatol 2020; 13:479-484. [PMID: 32801823 PMCID: PMC7399449 DOI: 10.2147/ccid.s262803] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 07/08/2020] [Indexed: 01/19/2023]
Abstract
Sun protection has been recommended by public health authorities to reduce the risk of keratinocyte and melanocyte tumors, yet some sun exposure is required for vitamin D synthesis. Frontal fibrosing alopecia (FFA) is a cicatricial alopecia that has been reported to have an association with facial photoprotection. The brief review proposes the hypothesis that FFA arises as a result of excessive facial photo-protection with a resultant disturbance in immunological homeostasis mediated via the aryl hydrocarbon receptor-kynurenine pathway axis (AHR/KP) leading to the collapse of immune privilege at the hair bulge.
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Affiliation(s)
- Rowland Noakes
- Queensland Institute of Dermatology, South Brisbane, Queensland, Australia
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13
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Chen KK, Minakuchi M, Wuputra K, Ku CC, Pan JB, Kuo KK, Lin YC, Saito S, Lin CS, Yokoyama KK. Redox control in the pathophysiology of influenza virus infection. BMC Microbiol 2020; 20:214. [PMID: 32689931 PMCID: PMC7370268 DOI: 10.1186/s12866-020-01890-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 07/01/2020] [Indexed: 01/07/2023] Open
Abstract
Triggered in response to external and internal ligands in cells and animals, redox homeostasis is transmitted via signal molecules involved in defense redox mechanisms through networks of cell proliferation, differentiation, intracellular detoxification, bacterial infection, and immune reactions. Cellular oxidation is not necessarily harmful per se, but its effects depend on the balance between the peroxidation and antioxidation cascades, which can vary according to the stimulus and serve to maintain oxygen homeostasis. The reactive oxygen species (ROS) that are generated during influenza virus (IV) infection have critical effects on both the virus and host cells. In this review, we outline the link between viral infection and redox control using IV infection as an example. We discuss the current state of knowledge on the molecular relationship between cellular oxidation mediated by ROS accumulation and the diversity of IV infection. We also summarize the potential anti-IV agents available currently that act by targeting redox biology/pathophysiology.
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Affiliation(s)
- Ker-Kong Chen
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, 807, Taiwan
- Department of Densitory, Kaohisung University Hospital, Kaohisung, 807, Taiwan
| | - Moeko Minakuchi
- Waseda Research Institute for Science and Engineering, Waseca University, Shinjuku, Tokyo, 162-8480, Japan
| | - Kenly Wuputra
- Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., San-Ming District, Kaohsiung, 80807, Taiwan
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung, 807, Taiwan
| | - Chia-Chen Ku
- Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., San-Ming District, Kaohsiung, 80807, Taiwan
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung, 807, Taiwan
| | - Jia-Bin Pan
- Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., San-Ming District, Kaohsiung, 80807, Taiwan
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung, 807, Taiwan
| | - Kung-Kai Kuo
- Department Surgery, Kaohsiung Medical University Hospital, Kaohsiung, 807, Taiwan
| | - Ying-Chu Lin
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, 807, Taiwan
| | - Shigeo Saito
- Waseda Research Institute for Science and Engineering, Waseca University, Shinjuku, Tokyo, 162-8480, Japan
- Saito Laboratory of Cell Technology Institute, Yalta, Tochigi, 329-1471, Japan
| | - Chang-Shen Lin
- Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., San-Ming District, Kaohsiung, 80807, Taiwan.
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung, 80424, Taiwan.
| | - Kazunari K Yokoyama
- Waseda Research Institute for Science and Engineering, Waseca University, Shinjuku, Tokyo, 162-8480, Japan.
- Graduate Institute of Medicine, Kaohsiung Medical University, 100 Shih-Chuan 1st Rd., San-Ming District, Kaohsiung, 80807, Taiwan.
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung, 807, Taiwan.
- Cell Therapy and Research Center, Kaohsiung Medical University Hospital, Kaohsiung, 807, Taiwan.
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14
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Tsatsakis A, Petrakis D, Nikolouzakis TK, Docea AO, Calina D, Vinceti M, Goumenou M, Kostoff RN, Mamoulakis C, Aschner M, Hernández AF. COVID-19, an opportunity to reevaluate the correlation between long-term effects of anthropogenic pollutants on viral epidemic/pandemic events and prevalence. Food Chem Toxicol 2020; 141:111418. [PMID: 32437891 PMCID: PMC7211730 DOI: 10.1016/j.fct.2020.111418] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 02/07/2023]
Abstract
Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)–B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics. Developmental exposure to environmental factors can disrupt the immune system. Long-term low-dose exposure to chemical mixtures is linked to imunodeficiency Immunodeficiency contributes to chronic diseases and the current Covid-19 pandemics. Environmental chemicals and microorganisms share similar molecular pathomechanisms (AhR pathway). Understanding the underlying pathomechanisms helps to improve public health.
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Affiliation(s)
- Aristidis Tsatsakis
- Laboratory of Toxicology, Medical School, University of Crete, Voutes, 71409 Heraklion, Crete, Greece; Department of Analytical and Forensic Medical Toxicology, Sechenov University, 2-4 Bolshaya Pirogovskaya st., 119991 Moscow, Russia; Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY 10461, USA.
| | - Demetrious Petrakis
- Laboratory of Toxicology, Medical School, University of Crete, Voutes, 71409 Heraklion, Crete, Greece.
| | | | - Anca Oana Docea
- Department of Toxicology, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania.
| | - Daniela Calina
- Department of Clinical Pharmacy, University of Medicine and Pharmacy of Craiova, 200349 Craiova, Romania.
| | - Marco Vinceti
- Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, I-41125 Modena, Italy.
| | - Marina Goumenou
- Laboratory of Toxicology, Medical School, University of Crete, Voutes, 71409 Heraklion, Crete, Greece
| | - Ronald N Kostoff
- School of Public Policy, Georgia Institute of Technology, Gainesville, VA, 20155, USA.
| | - Charalampos Mamoulakis
- Department of Urology, University General Hospital of Heraklion, Medical School, University of Crete, 71003 Heraklion, Crete, Greece.
| | - Michael Aschner
- Department of Analytical and Forensic Medical Toxicology, Sechenov University, 2-4 Bolshaya Pirogovskaya st., 119991 Moscow, Russia; Department of Molecular Pharmacology, Albert Einstein College of Medicine, New York, NY 10461, USA.
| | - Antonio F Hernández
- Department of Legal Medicine and Toxicology, University of Granada School of Medicine, 180016 Granada, Spain.
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15
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Münck NA, Roth J, Sunderkötter C, Ehrchen J. Aryl Hydrocarbon Receptor-Signaling Regulates Early Leishmania major-Induced Cytokine Expression. Front Immunol 2019; 10:2442. [PMID: 31749794 PMCID: PMC6843081 DOI: 10.3389/fimmu.2019.02442] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 10/01/2019] [Indexed: 02/05/2023] Open
Abstract
The early inflammatory skin micromilieu affects resistance in experimental infection with Leishmania major. We pursue the concept that macrophages, which take up parasites during early infection, exert decisive influence on the inflammatory micromilieu after infection. In order to analyze their distinctive potential, we identified differentially regulated genes of murine granuloma macrophages (GMΦ) from resistant and susceptible mice after their infection with metacyclic Leishmania major. We found induction of several cytokines in GMΦ from both strains and a stronger upregulation of the transcription factor aryl hydrocarbon receptor (AhR) in GMΦ from resistant mice. Using both an AhR agonist and antagonist we demonstrated that AhR is involved in Leishmania-induced production of TNF in macrophages. In vivo, single local injection of an AhR agonist in early lesions of susceptible mice caused an increased induction of Tnf and other cytokines in the skin. Importantly, local agonist treatment led to a reduction of disease severity, reduced parasite loads and a weaker Th2 response. Our results demonstrate that local activation of AhR has a beneficial effect in experimental leishmaniasis.
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Affiliation(s)
- Niels-Arne Münck
- Institute of Immunology, University of Münster, Münster, Germany.,Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Johannes Roth
- Institute of Immunology, University of Münster, Münster, Germany
| | - Cord Sunderkötter
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany.,Department of Dermatology, University of Münster, Münster, Germany.,Department of Dermatology and Venereology, Martin Luther University of Halle-Wittenberg, Halle, Germany
| | - Jan Ehrchen
- Department of Dermatology, University of Münster, Münster, Germany
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16
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Baker JR, Sakoff JA, McCluskey A. The aryl hydrocarbon receptor (AhR) as a breast cancer drug target. Med Res Rev 2019; 40:972-1001. [PMID: 31721255 DOI: 10.1002/med.21645] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 10/04/2019] [Accepted: 10/29/2019] [Indexed: 12/25/2022]
Abstract
Breast cancer is the most common cancer in women, with more than 1.7 million diagnoses worldwide per annum. Metastatic breast cancer remains incurable, and the presence of triple-negative phenotypes makes targeted treatment impossible. The aryl hydrocarbon receptor (AhR), most commonly associated with the metabolism of xenobiotic ligands, has emerged as a promising biological target for the treatment of this deadly disease. Ligands for the AhR can be classed as exogenous or endogenous and may have agonistic or antagonistic activity. It has been well reported that agonistic ligands may have potent and selective growth inhibition activity in a number of oncogenic cell lines, and one (aminoflavone) has progressed to phase I clinical trials for breast cancer sufferers. In this study, we examine the current state of the literature in this area and elucidate the promising advances that are being made in hijacking the cytosolic-to-nuclear pathway of the AhR for the possible future treatment of breast cancer.
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Affiliation(s)
- Jennifer R Baker
- Chemistry, School of Environmental & Life Sciences, the University of Newcastle, Callaghan, NSW, Australia
| | - Jennette A Sakoff
- Department of Medical Oncology, Calvary Mater Newcastle Hospital, Waratah, NSW, Australia
| | - Adam McCluskey
- Chemistry, School of Environmental & Life Sciences, the University of Newcastle, Callaghan, NSW, Australia
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17
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Sigle LT, McGraw EA. Expanding the canon: Non-classical mosquito genes at the interface of arboviral infection. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2019; 109:72-80. [PMID: 30970277 DOI: 10.1016/j.ibmb.2019.04.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 03/10/2019] [Accepted: 04/01/2019] [Indexed: 06/09/2023]
Abstract
Mosquito transmitted viruses cause significant morbidity and mortality in human populations. Despite the use of insecticides and other measures of vector control, arboviral diseases are on the rise. One potential solution for limiting disease transmission to humans is to render mosquitoes refractory to viral infection through genetic modification. Substantial research effort in Drosophila, Aedes and Anopheles has helped to define the major innate immune pathways, including Toll, IMD, Jak/Stat and RNAi, however we still have an incomplete picture of the mosquito antiviral response. Transcriptional profiles of virus-infected insects reveal a much wider range of pathways activated by the process of infection. Within these lists of genes are unexplored mosquito candidates of viral defense. Wolbachia species are endosymbiotic bacteria that naturally limit arboviral infection in mosquitoes. Our understanding of the Wolbachia-mediated viral blocking mechanism is poor, but it does not appear to operate via the classical immune pathways. Herein, we reviewed the transcriptomic response of mosquitoes to multiple viral species and put forth consensus gene types/families outside the immune canon whose expression responds to infection, including cytoskeleton and cellular trafficking, the heat shock response, cytochromes P450, cell proliferation, chitin and small RNAs. We then examine emerging evidence for their functional role in viral resistance in diverse insect and mammalian hosts and their potential role in Wolbachia-mediated viral blocking. These candidate gene families offer novel avenues for research into the nature of insect viral defense.
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Affiliation(s)
- Leah T Sigle
- Center for Infectious Disease Dynamics, Department of Entomology, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Elizabeth A McGraw
- Center for Infectious Disease Dynamics, Department of Entomology, Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, PA, 16802, USA.
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18
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Duan Z, Deng S, Ji X, Zhao J, Yuan C, Gao H. Nuclear localization of Newcastle disease virus matrix protein promotes virus replication by affecting viral RNA synthesis and transcription and inhibiting host cell transcription. Vet Res 2019; 50:22. [PMID: 30894203 PMCID: PMC6425612 DOI: 10.1186/s13567-019-0640-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 02/11/2019] [Indexed: 01/24/2023] Open
Abstract
Nuclear localization of paramyxovirus proteins is crucial for virus life cycle, including the regulation of viral replication and the evasion of host immunity. We previously showed that a recombinant Newcastle disease virus (NDV) with nuclear localization signal mutation in the matrix (M) protein results in a pathotype change and attenuates viral pathogenicity in chickens. However, little is known about the nuclear localization functions of NDV M protein. In this study, the potential functions of the M protein in the nucleus were investigated. We first demonstrate that nuclear localization of the M protein could not only promote the cytopathogenicity of NDV but also increase viral RNA synthesis and transcription efficiency in DF-1 cells. Using microarray analysis, we found that nuclear localization of the M protein might inhibit host cell transcription, represented by numerous up-regulating genes associated with transcriptional repressor activity and down-regulating genes associated with transcriptional activator activity. The role of representative up-regulated gene prospero homeobox 1 (PROX1) and down-regulated gene aryl hydrocarbon receptor (AHR) in the replication of NDV was then evaluated. The results show that siRNA-mediated knockdown of PROX1 or AHR significantly reduced or increased the viral RNA synthesis and viral replication, respectively, demonstrating the important roles of the expression changes of these genes in NDV replication. Together, our findings demonstrate for the first time that nuclear localization of NDV M protein promotes virus replication by affecting viral RNA synthesis and transcription and inhibiting host cell transcription, improving our understanding of the molecular mechanism of NDV replication and pathogenesis.
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Affiliation(s)
- Zhiqiang Duan
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, China. .,College of Animal Science, Guizhou University, Guiyang, China.
| | - Shanshan Deng
- College of Animal Science, Guizhou University, Guiyang, China
| | - Xinqin Ji
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, China.,College of Animal Science, Guizhou University, Guiyang, China
| | - Jiafu Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, China.,College of Animal Science, Guizhou University, Guiyang, China
| | - Chao Yuan
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, China.,College of Animal Science, Guizhou University, Guiyang, China
| | - Hongbo Gao
- Key Laboratory of Animal Genetics, Breeding and Reproduction in The Plateau Mountainous Region, Ministry of Education, Guizhou University, Guiyang, China.,College of Animal Science, Guizhou University, Guiyang, China
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19
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Esser C, Haarmann-Stemmann T, Hochrath K, Schikowski T, Krutmann J. AHR and the issue of immunotoxicity. CURRENT OPINION IN TOXICOLOGY 2018. [DOI: 10.1016/j.cotox.2018.03.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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20
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Burleson SCM, Freebern WJ, Burleson FG, Burleson GR, Johnson VJ, Luebke RW. Host Resistance Assays. Methods Mol Biol 2018; 1803:117-145. [PMID: 29882137 DOI: 10.1007/978-1-4939-8549-4_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The goal of immunotoxicity testing is to obtain data useful for immunotoxicity safety assessment. Guidance in the performance of immunotoxicity safety evaluations is provided in documents from the US EPA for chemicals and the ICH S8 document for pharmaceuticals. The ICH S8 document outlines a tiered approach that includes (1) standard toxicity studies with associated hematology, immune system organ weights, and histopathology data; (2) functional assays, such as cytotoxic T lymphocyte (CTL) assays, natural killer (NK) cell assays, respiratory burst, phagocytosis, and T-cell-dependent antibody response (TDAR) assays; and (3) host resistance assays. Host resistance assays are considered the gold standard in immunotoxicity testing and provide a critical overview of the extent to which innate, adaptive, and homeostatic regulatory immune functions are integrated to protect the host. Both comprehensive and targeted host resistance assays are available, each with distinct advantages. This chapter serves to provide a general overview of the various assays that may be used, as well as a summary of procedures.
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Affiliation(s)
| | - Wendy Jo Freebern
- Bristol-Myers Squibb Company, Immunotoxicology, New Brunswick, NJ, USA
| | | | - Gary R Burleson
- Burleson Research Technologies, Inc. (BRT), Morrisville, NC, USA
| | - Victor J Johnson
- Burleson Research Technologies, Inc. (BRT), Morrisville, NC, USA
| | - Robert W Luebke
- United States Environmental Protection Agency, Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, National Health and Environmental Effects Laboratory, Office of Research and Development, Research Triangle Park, NC, USA.,Burleson Research Technologies, Inc., Morrisville, NC, USA
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21
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Fiorito F, Santamaria R, Irace C, De Martino L, Iovane G. 2,3,7,8-tetrachlorodibenzo-p-dioxin and the viral infection. ENVIRONMENTAL RESEARCH 2017; 153:27-34. [PMID: 27883971 DOI: 10.1016/j.envres.2016.11.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 10/13/2016] [Accepted: 11/09/2016] [Indexed: 06/06/2023]
Abstract
Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a widespread highly toxic environmental contaminant, suppresses immune response and leads to an increased susceptibility to infectious agents. In particular, several studies have provided evidence that TCDD decreases resistance to numerous viruses. Indeed, in vivo and in vitro investigations showed that the presence of TCDD is able to interfere with the replication of both human and animal viruses, such as influenza A viruses, coxsackie virus B3, immunodeficiency virus type-1 (HIV-1), cytomegalovirus (CMV), herpes simplex II, and bovine herpesvirus 1. Moreover, TCDD could induce an exacerbation of latent infection produced by HIV-1, CMV or Epstein-Barr virus. In this review, we first describe the general effects of TCDD exposure on mammalian cells, then we focus on its influence on the viral infections. Overall, the available data support the concept that TCDD exposure may act as an additional risk factor in promoting of viral diseases.
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Affiliation(s)
- Filomena Fiorito
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy; Istituto Zooprofilattico Sperimentale del Mezzogiorno, Via Salute 2, Portici, 80055 Naples, Italy.
| | - Rita Santamaria
- Department of Pharmacy, University of Naples "Federico II", Via D. Montesano 49, 80131 Naples, Italy
| | - Carlo Irace
- Department of Pharmacy, University of Naples "Federico II", Via D. Montesano 49, 80131 Naples, Italy
| | - Luisa De Martino
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy.
| | - Giuseppe Iovane
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, 80137 Naples, Italy
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22
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Richter J, Jimenez J, Nagatomo T, Toelen J, Brady P, Salaets T, Lesage F, Vanoirbeek J, Deprest J. Proton-pump inhibitor omeprazole attenuates hyperoxia induced lung injury. J Transl Med 2016; 14:247. [PMID: 27567616 PMCID: PMC5002203 DOI: 10.1186/s12967-016-1009-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2016] [Accepted: 08/16/2016] [Indexed: 01/18/2023] Open
Abstract
Background The administration of supplemental oxygen to treat ventilatory insufficiency may lead to the formation of reactive oxygen species and subsequent tissue damage. Cytochrome P4501A1 (CYP1A1) can modulate hyperoxic lung injury by a currently unknown mechanism. Our objective was to evaluate the effect of administration of omeprazole on the induction of CYP1A1 and its influence on hyperoxic lung injury in an established preterm rabbit model. Methods Omeprazole was administered either (1) directly to the fetus, (2) to the mother or (3) after birth to the pups in different doses (2–10 or 20 mg/kg). Controls were injected with the same amount of saline. Pups were housed in normoxia (21 %) or hyperoxia (>95 %) for 5 days. Outcome parameters were induction of CYP1A1 measured by real-time polymerase chain reaction (RT-PCR) immediately after delivery, at day 3 and day 5 as well as lung function, morphometry and immunohistochemistry assessed at day 5 of life. Transcriptome analysis was used to define the targeted pathways. Results Daily neonatal injections demonstrated a dose-dependent increase in CYP1A1. Lung function tests showed a significant improvement in tissue damping, tissue elasticity, total lung capacity, static compliance and elastance. Morphometry revealed a more developed lung architecture with thinned septae in animals treated with the highest dose (20 mg/kg) of omeprazole. Surfactant protein B, vascular endothelial growth factor and its receptor were significantly increased on immunohistochemical stainings after omeprazole treatment. Conclusions Neonatal administration of omeprazole induces CYP1A1 in a dose-dependent matter and combined pre- and postnatal administration attenuates hyperoxic lung injury in preterm rabbits, even with the lowest dose of omeprazole without clear CYP1A1 induction. Electronic supplementary material The online version of this article (doi:10.1186/s12967-016-1009-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jute Richter
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium. .,Division Woman and Child, University Hospitals Leuven, Leuven, Belgium. .,Clinical Department of Obstetrics and Gynaecology and Academic Department of Development and Regeneration, Organ System Cluster, University Hospitals of Leuven, Herestraat 49, 3000, Leuven, Belgium.
| | - Julio Jimenez
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Departamento Ginecología y Obstetricia, Clínica Alemana, Santiago, Chile
| | - Taro Nagatomo
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Department of Neonatology, Ehime Prefectural Central Hospital, Matsuyama, Japan
| | - Jaan Toelen
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Division Woman and Child, University Hospitals Leuven, Leuven, Belgium
| | - Paul Brady
- Centre for Human Genetics, University Hospitals Leuven, KU Leuven, Leuven, Belgium
| | - Thomas Salaets
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Division Woman and Child, University Hospitals Leuven, Leuven, Belgium
| | - Flore Lesage
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium
| | - Jeroen Vanoirbeek
- Laboratory of Occupational and Environmental Toxicology, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Jan Deprest
- Department of Development and Regeneration, Faculty of Medicine, KU Leuven, Leuven, Belgium.,Division Woman and Child, University Hospitals Leuven, Leuven, Belgium
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Holen E, Olsvik PA. β-naphthoflavone interferes with cyp1c1, cox2 and IL-8 gene transcription and leukotriene B4 secretion in Atlantic cod (Gadus morhua) head kidney cells during inflammation. FISH & SHELLFISH IMMUNOLOGY 2016; 54:128-134. [PMID: 27041667 DOI: 10.1016/j.fsi.2016.03.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/18/2016] [Accepted: 03/21/2016] [Indexed: 06/05/2023]
Abstract
The objective of this study was to evaluate how β-naphthoflavone interacts with lipopolysaccharide (LPS) and polyinosinic acid: polycytidylic acid (poly I: C) induced innate immune parameters as well as phase I and phase II detoxification enzymes in head kidney cells isolated from Atlantic cod. β-naphthoflavone is a pure agonist of aryl hydrocarbon receptor (AhR) while LPS and poly I: C are not. β-naphthoflavone was added to head kidney leukocytes alone or together with LPS or poly I: C and the responses were evaluated in terms of protein and gene expression. The results showed that β-naphthoflavone (25 nM), with and without LPS, significantly induced cytochrome P450 (cyp1c) transcription in cod head kidney cells. β-naphthoflavone (100 nM) in the presence of the virus mimic, poly I: C, also increased cyp1c1transcription. LPS induced cyp1c1, cyclooxygenase 2 (cox2), interleukin 1β (IL-1β), interleukin 6 (IL-6) and interleukin 8 (IL-8) transcription, genes that were not affected by the tested β-naphthoflavone concentrations alone. However, β-naphthoflavone (25 and 50 nM) strengthened LPS induced cox2 and IL-8 transcription. Cod head kidney cells exposed to β-naphthoflavone concentrations ranging from 25 to 100 nM, with and without LPS or poly I: C, expressed AhR protein. LPS or β-naphthoflavone (5-50 nM) significantly induced leukotriene B4 (LTB4) secretion compared to control. In conclusion, this study suggests that β-naphthoflavone could interfere with LPS induced immune cell signaling in cod head kidney cells.
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Affiliation(s)
- Elisabeth Holen
- National Institute of Nutrition and Seafood Research (NIFES), P. B. 2029 Nordnes, 5817, Bergen, Norway.
| | - Pål A Olsvik
- National Institute of Nutrition and Seafood Research (NIFES), P. B. 2029 Nordnes, 5817, Bergen, Norway
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Bogomolni A, Frasca S, Levin M, Matassa K, Nielsen O, Waring G, De Guise S. In Vitro Exposure of Harbor Seal Immune Cells to Aroclor 1260 Alters Phocine Distemper Virus Replication. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2016; 70:121-132. [PMID: 26142119 DOI: 10.1007/s00244-015-0178-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 06/06/2015] [Indexed: 06/04/2023]
Abstract
In the last 30 years, several large-scale marine mammal mortality events have occurred, often in close association with highly polluted regions, leading to suspicions that contaminant-induced immunosuppression contributed to these epizootics. Some of these recent events also identified morbillivirus as a cause of or contributor to death. The role of contaminant exposures regarding morbillivirus mortality is still unclear. The results of this study aimed to address the potential for a mixture of polychlorinated biphenyls (PCBs), specifically Aroclor 1260, to alter harbor seal T-lymphocyte proliferation and to assess if exposure resulted in increased likelihood of phocine distemper virus (PDV USA 2006) to infect susceptible seals in an in vitro system. Exposure of peripheral blood mononuclear cells to Aroclor 1260 did not significantly alter lymphocyte proliferation (1, 5, 10, and 20 ppm). However, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR), lymphocytes exposed to 20 ppm Aroclor 1260 exhibited a significant decrease in PDV replication at day 7 and a significant increase at day 11 compared with unexposed control cells. Similar and significant differences were apparent on exposure to Aroclor 1260 in monocytes and supernatant. The results here indicate that in harbor seals, Aroclor 1260 exposure results in a decrease in virus early during infection and an increase during late infection. The consequences of this contaminant-induced infection pattern in a highly susceptible host could result in a greater potential for systemic infection with greater viral load, which could explain the correlative findings seen in wild populations exposed to a range of persistent contaminants that suffer from morbillivirus epizootics.
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Affiliation(s)
- Andrea Bogomolni
- Department of Pathobiology and Veterinary Science, University of Connecticut, 61 North Eagleville Rd., Storrs, CT, 06268, USA.
- Woods Hole Oceanographic Institution, 266 Woods Hole, Rd. #MS 50, Woods Hole, MA, 02543, USA.
| | - Salvatore Frasca
- Department of Pathobiology and Veterinary Science, University of Connecticut, 61 North Eagleville Rd., Storrs, CT, 06268, USA
| | - Milton Levin
- Department of Pathobiology and Veterinary Science, University of Connecticut, 61 North Eagleville Rd., Storrs, CT, 06268, USA
| | - Keith Matassa
- Pacific Marine Mammal Center, 20612 Laguna Canyon Rd, Laguna Beach, CA, 92651, USA
| | - Ole Nielsen
- Department of Fisheries and Oceans Canada, Central and Arctic Region, 501 University Crescent, Winnipeg, MB, R3T 2N6, Canada
| | - Gordon Waring
- National Marine Fisheries Service, Northeast Fisheries Science Center, 166 Woods Hole Rd., Woods Hole, MA, USA
| | - Sylvain De Guise
- Department of Pathobiology and Veterinary Science, University of Connecticut, 61 North Eagleville Rd., Storrs, CT, 06268, USA
- Connecticut Sea Grant College Program, 1080 Shennecossett Road, Groton, CT, 06340, USA
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Thatcher TH, Williams MA, Pollock SJ, McCarthy CE, Lacy SH, Phipps RP, Sime PJ. Endogenous ligands of the aryl hydrocarbon receptor regulate lung dendritic cell function. Immunology 2015; 147:41-54. [PMID: 26555456 DOI: 10.1111/imm.12540] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 09/28/2015] [Accepted: 10/01/2015] [Indexed: 02/06/2023] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a transcription factor that has been extensively studied as a regulator of toxicant metabolism. However, recent evidence indicates that the AhR also plays an important role in immunity. We hypothesized that the AhR is a novel, immune regulator of T helper type 2 (Th2) -mediated allergic airway disease. Here, we report that AhR-deficient mice develop increased allergic responses to the model allergen ovalbumin (OVA), which are driven in part by increased dendritic cell (DC) functional activation. AhR knockout (AhR(-/-) ) mice sensitized and challenged with OVA develop an increased inflammatory response in the lung compared with wild-type controls, with greater numbers of inflammatory eosinophils and neutrophils, greater T-cell proliferation, greater production of Th2 cytokines, and higher levels of OVA-specific IgE and IgG1. Lung DCs from AhR(-/-) mice stimulated antigen-specific proliferation and Th2 cytokine production by naive T cells in vitro. Additionally, AhR(-/-) DCs produced higher levels of tumour necrosis factor-α and interleukin-6, which promote Th2 differentiation, and expressed higher cell surface levels of stimulatory MHC Class II and CD86 molecules. Overall, loss of the AhR was associated with enhanced T-cell activation by pulmonary DCs and heightened pro-inflammatory allergic responses. This suggests that endogenous AhR ligands are involved in the normal regulation of Th2-mediated immunity in the lung via a DC-dependent mechanism. Therefore, the AhR may represent an important target for therapeutic intervention in allergic airways inflammation.
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Affiliation(s)
- Thomas H Thatcher
- Division of Pulmonary and Critical Care Medicine, University of Rochester, Rochester, NY, USA
| | - Marc A Williams
- Division of Pulmonary and Critical Care Medicine, University of Rochester, Rochester, NY, USA.,Department of Environmental Medicine, University of Rochester, Rochester, NY, USA
| | - Stephen J Pollock
- Department of Environmental Medicine, University of Rochester, Rochester, NY, USA.,Lung Biology and Disease Program, University of Rochester, Rochester, NY, USA
| | - Claire E McCarthy
- Department of Environmental Medicine, University of Rochester, Rochester, NY, USA
| | - Shannon H Lacy
- Department of Environmental Medicine, University of Rochester, Rochester, NY, USA
| | - Richard P Phipps
- Department of Environmental Medicine, University of Rochester, Rochester, NY, USA.,Lung Biology and Disease Program, University of Rochester, Rochester, NY, USA
| | - Patricia J Sime
- Division of Pulmonary and Critical Care Medicine, University of Rochester, Rochester, NY, USA.,Department of Environmental Medicine, University of Rochester, Rochester, NY, USA.,Lung Biology and Disease Program, University of Rochester, Rochester, NY, USA
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Stockinger B, Di Meglio P, Gialitakis M, Duarte JH. The aryl hydrocarbon receptor: multitasking in the immune system. Annu Rev Immunol 2014; 32:403-32. [PMID: 24655296 DOI: 10.1146/annurev-immunol-032713-120245] [Citation(s) in RCA: 662] [Impact Index Per Article: 66.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The aryl hydrocarbon receptor (AhR), for many years almost exclusively studied by the pharmacology/toxicology field for its role in mediating the toxicity of xenobiotics such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), has more recently attracted the attention of immunologists. The evolutionary conservation of this transcription factor and its widespread expression in the immune system point to important physiological functions that are slowly being unraveled. In particular, the emphasis is now shifting from the role of AhR in the xenobiotic pathway toward its mode of action in response to physiological ligands. In this article, we review the current understanding of the molecular interactions and functions of AhR in the immune system in steady state and in the presence of infection and inflammation, with a focus on barrier organs such as the skin, the gut, and the lung.
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Affiliation(s)
- Brigitta Stockinger
- Division of Molecular Immunology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, United Kingdom; , , ,
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Spink BC, Bloom MS, Wu S, Sell S, Schneider E, Ding X, Spink DC. Analysis of the AHR gene proximal promoter GGGGC-repeat polymorphism in lung, breast, and colon cancer. Toxicol Appl Pharmacol 2014; 282:30-41. [PMID: 25447411 DOI: 10.1016/j.taap.2014.10.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 09/26/2014] [Accepted: 10/27/2014] [Indexed: 02/05/2023]
Abstract
The aryl hydrocarbon receptor (AhR) regulates expression of numerous genes, including those of the CYP1 gene family. With the goal of determining factors that control AHR gene expression, our studies are focused on the role of the short tandem repeat polymorphism, (GGGGC)n, located in the proximal promoter of the human AHR gene. When luciferase constructs containing varying GGGGC repeats were transfected into cancer cell lines derived from the lung, colon, and breast, the number of GGGGC repeats affected AHR promoter activity. The number of GGGGC repeats was determined in DNA from 327 humans and from 38 samples representing 5 species of non-human primates. In chimpanzees and 3 species of macaques, only (GGGGC)2 alleles were observed; however, in western gorilla, (GGGGC)n alleles with n=2, 4, 5, 6, 7, and 8 were identified. In all human populations examined, the frequency of (GGGGC)n was n=4>5≫2, 6. When frequencies of the (GGGGC)n alleles in DNA from patients with lung, colon, or breast cancer were evaluated, the occurrence of (GGGGC)2 was found to be 8-fold more frequent among lung cancer patients in comparison with its incidence in the general population, as represented by New York State neonates. Analysis of matched tumor and non-tumor DNA samples from the same individuals provided no evidence of microsatellite instability. These studies indicate that the (GGGGC)n short tandem repeats are inherited, and that the (GGGGC)2 allele in the AHR proximal promoter region should be further investigated with regard to its potential association with lung cancer susceptibility.
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Affiliation(s)
- Barbara C Spink
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Michael S Bloom
- Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States
| | - Susan Wu
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States
| | - Stewart Sell
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States; Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States
| | - Erasmus Schneider
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States; Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States
| | - Xinxin Ding
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States; Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States; Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States
| | - David C Spink
- Wadsworth Center, New York State Department of Health, Albany, NY 12201, United States; Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, NY 12201, United States.
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Holen E, Olsvik PA. Aryl hydrocarbon receptor protein and Cyp1A1 gene induction by LPS and phenanthrene in Atlantic cod (Gadus morhua) head kidney cells. FISH & SHELLFISH IMMUNOLOGY 2014; 40:384-391. [PMID: 25058847 DOI: 10.1016/j.fsi.2014.07.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 07/10/2014] [Accepted: 07/12/2014] [Indexed: 06/03/2023]
Abstract
The objective of this study was to evaluate interactions between environmental toxicants and cod immune cells during inflammation. Phenanthrene is abundant in plant oils (rapeseed, palm, and soya oil) as compared to fish oils, and consequently constitute an undesirable element in plant replacement diets in aquaculture. Phenanthrene was added to head kidney cell cultures, alone or together with LPS (lipopolysaccharide) or poly I: C (polyinosinic acid: polycytidylic acid), and the responses were evaluated in terms of protein and gene expression. The results showed that LPS, poly I: C or phenanthrene, added to the cultures separately, induced aryl hydrocarbon receptor (AhR) protein expression. Phenanthrene treatment in combination with LPS induced AhR protein expression and Cyp1A1 gene transcription, which not was observed combining poly I: C and phenanthrene. Phenanthrene exposure up regulated the transcription of common stress and detoxification enzymes like catalase, caspase 3 and glutathione S-transferase alfa 3 subunit B (GSTAB3), while LPS exposure alone or combined with phenanthrene down regulated GSTAB3 and catalase in cod leukocytes. It seems clear that immune regulation and phenanthrene induced signaling pathways interact; transcriptional down regulation of detoxification and antioxidant enzymes by LPS could indicate that combating bacterial infections is the number one priority in these cells, and that AhR and Cyp1A1 is somehow involved in this signaling cascade. LPS seems to affect the mitogen activated protein kinases (MAPKs) pathways (P-p38 and ERK1/2) thus modulating the AhR protein and Cyp1A1 gene transcription, while phenanthrene possibly activates AhR by ligand binding.
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Affiliation(s)
- Elisabeth Holen
- National Institute of Nutrition and Seafood Research (NIFES), P. B. 2029 Nordnes, 5817 Bergen, Norway.
| | - Pål Asgeir Olsvik
- National Institute of Nutrition and Seafood Research (NIFES), P. B. 2029 Nordnes, 5817 Bergen, Norway
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Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates capacity of hematopoietic stem cells to undergo lymphocyte differentiation. Toxicol Appl Pharmacol 2014; 277:172-82. [PMID: 24709672 DOI: 10.1016/j.taap.2014.03.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 03/17/2014] [Accepted: 03/22/2014] [Indexed: 12/14/2022]
Abstract
The process of hematopoiesis, characterized by long-term self-renewal and multi-potent lineage differentiation, has been shown to be regulated in part by the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous contaminant and the most potent AHR agonist, also modulates regulation of adult hematopoietic stem and progenitor cell (HSC/HPC) homeostasis. However, the effect of developmental TCDD exposure on early life hematopoiesis has not been fully explored. Given the inhibitory effects of TCDD on hematopoiesis and lymphocyte development, we hypothesized that in utero exposure to TCDD would alter the functional capacity of fetal HSC/HPCs to complete lymphocyte differentiation. To test this hypothesis, we employed a co-culture system designed to facilitate the maturation of progenitor cells to either B or T lymphocytes. Furthermore, we utilized an innovative limiting dilution assay to precisely quantify differences in lymphocyte differentiation between HSC/HPCs obtained from fetuses of dams exposed to 3μg/kg TCDD or control. We found that the AHR is transcribed in yolk sac hematopoietic cells and is transcriptionally active as early as gestational day (GD) 7.5. Furthermore, the number of HSC/HPCs present in the fetal liver on GD 14.5 was significantly increased in fetuses whose mothers were exposed to TCDD throughout pregnancy. Despite this increase in HSC/HPC cell number, B and T lymphocyte differentiation is decreased by approximately 2.5 fold. These findings demonstrate that inappropriate developmental AHR activation in HSC/HPCs adversely impacts lymphocyte differentiation and may have consequences for lymphocyte development in the bone marrow and thymus later in life.
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Toward understanding the role of aryl hydrocarbon receptor in the immune system: current progress and future trends. BIOMED RESEARCH INTERNATIONAL 2014; 2014:520763. [PMID: 24527450 PMCID: PMC3914515 DOI: 10.1155/2014/520763] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 10/14/2013] [Indexed: 01/03/2023]
Abstract
The immune system is regulated by distinct signaling pathways that control the development and function of the immune cells. Accumulating evidence suggest that ligation of aryl hydrocarbon receptor (Ahr), an environmentally responsive transcription factor, results in multiple cross talks that are capable of modulating these pathways and their downstream responsive genes. Most of the immune cells respond to such modulation, and many inflammatory response-related genes contain multiple xenobiotic-responsive elements (XREs) boxes upstream. Active research efforts have investigated the physiological role of Ahr in inflammation and autoimmunity using different animal models. Recently formed paradigm has shown that activation of Ahr by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 3,3′-diindolylmethane (DIM) prompts the differentiation of CD4+Foxp3+ regulatory T cells (Tregs) and inhibits T helper (Th)-17 suggesting that Ahr is an innovative therapeutic strategy for autoimmune inflammation. These promising findings generate a basis for future clinical practices in humans. This review addresses the current knowledge on the role of Ahr in different immune cell compartments, with a particular focus on inflammation and autoimmunity.
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Budinsky RA, Schrenk D, Simon T, Van den Berg M, Reichard JF, Silkworth JB, Aylward LL, Brix A, Gasiewicz T, Kaminski N, Perdew G, Starr TB, Walker NJ, Rowlands JC. Mode of action and dose–response framework analysis for receptor-mediated toxicity: The aryl hydrocarbon receptor as a case study. Crit Rev Toxicol 2013; 44:83-119. [DOI: 10.3109/10408444.2013.835787] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Rider CV, Boekelheide K, Catlin N, Gordon CJ, Morata T, Selgrade MK, Sexton K, Simmons JE. Cumulative risk: toxicity and interactions of physical and chemical stressors. Toxicol Sci 2013; 137:3-11. [PMID: 24154487 DOI: 10.1093/toxsci/kft228] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Recent efforts to update cumulative risk assessment procedures to incorporate nonchemical stressors ranging from physical to psychosocial reflect increased interest in consideration of the totality of variables affecting human health and the growing desire to develop community-based risk assessment methods. A key roadblock is the uncertainty as to how nonchemical stressors behave in relationship to chemical stressors. Physical stressors offer a reasonable starting place for measuring the effects of nonchemical stressors and their modulation of chemical effects (and vice versa), as they clearly differ from chemical stressors; and "doses" of many physical stressors are more easily quantifiable than those of psychosocial stressors. There is a commonly held belief that virtually nothing is known about the impact of nonchemical stressors on chemically mediated toxicity or the joint impact of coexposure to chemical and nonchemical stressors. Although this is generally true, there are several instances where a substantial body of evidence exists. A workshop titled "Cumulative Risk: Toxicity and Interactions of Physical and Chemical Stressors" held at the 2013 Society of Toxicology Annual Meeting provided a forum for discussion of research addressing the toxicity of physical stressors and what is known about their interactions with chemical stressors, both in terms of exposure and effects. Physical stressors including sunlight, heat, radiation, infectious disease, and noise were discussed in reference to identifying pathways of interaction with chemical stressors, data gaps, and suggestions for future incorporation into cumulative risk assessments.
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Affiliation(s)
- Cynthia V Rider
- * Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709
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Sherr DH, Monti S. The role of the aryl hydrocarbon receptor in normal and malignant B cell development. Semin Immunopathol 2013; 35:705-16. [PMID: 23942720 PMCID: PMC3824572 DOI: 10.1007/s00281-013-0390-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 07/01/2013] [Indexed: 12/14/2022]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor historically studied for its role in environmental chemical-mediated toxicity and carcinogenicity. In the last 5 years, however, it has become clear that the AhR, presumably activated by endogenous ligand(s), plays an important role in immune system development and function. Other articles in this edition summarize AhR function during T cell and antigen-presenting cell development and function, including the effects of AhR activation on dendritic cell function, T cell skewing, inflammation, and autoimmune disease. Here, we focus on AhR expression and function during B cell differentiation. Studies exploiting immunosuppressive environmental chemicals to probe the role of the AhR in humoral immunity are also reviewed to illustrate the multiple levels at which a “nominally activated” AhR could control B cell differentiation from the hematopoietic stem cell through the pro-B cell, mature B cell, and antibody-secreting plasma cell stages. Finally, a putative role for the AhR in the basic biology of B cell malignancies, many of which have been associated with exposure to environmental AhR ligands, is discussed.
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Affiliation(s)
- David H Sherr
- Department of Environmental Health, Boston University School of Public Health, 72 East Concord Street (R-408), Boston, MA, 02118, USA,
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Hao N, Whitelaw ML. The emerging roles of AhR in physiology and immunity. Biochem Pharmacol 2013; 86:561-70. [PMID: 23856287 DOI: 10.1016/j.bcp.2013.07.004] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/04/2013] [Accepted: 07/04/2013] [Indexed: 02/06/2023]
Abstract
The aryl hydrocarbon receptor (AhR) is traditionally defined as a transcriptional regulator involved in adaptive xenobiotic response, however, emerging evidence supports physiological functions of AhR in normal cell development and immune response. The role of AhR in immunomodulation is multi-dimensional. On the one hand, activation of AhR by TCDD and other ligands leads to profound immunosuppression, potentially via skewed Th1/Th2 cell balance toward Th1 dominance, and boosted Treg cell differentiation. On the other hand, activation of AhR can also induce Th17 cell polarization and increase the severity of autoimmune disease. In addition to T lymphocytes, the AhR also appears to play a vital role in B cell maturation, and regulates the activity of macrophages, dendritic cells and neutrophils following lipopolysaccharide challenge or influenza virus infection. In these scenarios, activation of AhR is associated with decreased host response and reduced survival. Furthermore, gene knock out studies suggest that AhR is indispensable for the postnatal maintenance of intestinal intraepithelial lymphocytes and skin-resident dendritic epidermal gamma delta T cells, providing a potential link between AhR and gut immunity and wound healing. It is well accepted that the magnitude and the type of immune response is dependent on the local cytokine milieu and the AhR appears to be one of the key factors involved in the fine turning of this cytokine balance.
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Affiliation(s)
- Nan Hao
- School of Molecular and Biomedical Science (Biochemistry), The University of Adelaide, Adelaide, South Australia 5005, Australia.
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Mohan M, Kaushal D, Aye PP, Alvarez X, Veazey RS, Lackner AA. Focused examination of the intestinal lamina propria yields greater molecular insight into mechanisms underlying SIV induced immune dysfunction. PLoS One 2012; 7:e34561. [PMID: 22511950 PMCID: PMC3325268 DOI: 10.1371/journal.pone.0034561] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2011] [Accepted: 03/05/2012] [Indexed: 12/12/2022] Open
Abstract
Background The Gastrointestinal (GI) tract is critical to AIDS pathogenesis as it is the primary site for viral transmission and a major site of viral replication and CD4+ T cell destruction. Consequently GI disease, a major complication of HIV/SIV infection can facilitate translocation of lumenal bacterial products causing localized/systemic immune activation leading to AIDS progression. Methodology/Principal Findings To better understand the molecular mechanisms underlying GI disease we analyzed global gene expression profiles sequentially in the intestine of the same animals prior to and at 21 and 90d post SIV infection (PI). More importantly we maximized information gathering by examining distinct mucosal components (intraepithelial lymphocytes, lamina propria leukocytes [LPL], epithelium and fibrovascular stroma) separately. The use of sequential intestinal resections combined with focused examination of distinct mucosal compartments represents novel approaches not previously attempted. Here we report data pertaining to the LPL. A significant increase (±1.7-fold) in immune defense/inflammation, cell adhesion/migration, cell signaling, transcription and cell division/differentiation genes were observed at 21 and 90d PI. Genes associated with the JAK-STAT pathway (IL21, IL12R, STAT5A, IL10, SOCS1) and T-cell activation (NFATc1, CDK6, Gelsolin, Moesin) were notably upregulated at 21d PI. Markedly downregulated genes at 21d PI included IL17D/IL27 and IL28B/IFNγ3 (anti-HIV/viral), activation induced cytidine deaminase (B-cell function) and approximately 57 genes regulating oxidative phosphorylation, a critical metabolic shift associated with T-cell activation. The 90d transcriptome revealed further augmentation of inflammation (CXCL11, chitinase-1, JNK3), immune activation (CD38, semaphorin7A, CD109), B-cell dysfunction (CD70), intestinal microbial translocation (Lipopolysaccharide binding protein) and mitochondrial antiviral signaling (NLRX1) genes. Reduced expression of CD28, CD4, CD86, CD93, NFATc1 (T-cells), TLR8, IL8, CCL18, DECTIN1 (macrophages), HLA-DOA and GPR183 (B-cells) at 90d PI suggests further deterioration of overall immune function. Conclusions/Significance The reported transcriptional signatures provide significant new details on the molecular pathology of HIV/SIV induced GI disease and provide new opportunity for future investigation.
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Affiliation(s)
- Mahesh Mohan
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Deepak Kaushal
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Pyone P. Aye
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Xavier Alvarez
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Ronald S. Veazey
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Andrew A. Lackner
- Division of Comparative Pathology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
- * E-mail:
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Schulz VJ, Smit JJ, Huijgen V, Bol-Schoenmakers M, van Roest M, Kruijssen LJW, Fiechter D, Hassing I, Bleumink R, Safe S, van Duursen MBM, van den Berg M, Pieters RHH. Non-dioxin-like AhR ligands in a mouse peanut allergy model. Toxicol Sci 2012; 128:92-102. [PMID: 22491429 DOI: 10.1093/toxsci/kfs131] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Recently, we have shown that AhR activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suppresses sensitization to peanut at least in part by inducing a functional shift toward CD4(+)CD25(+)Foxp3(+) T cells. Next to TCDD, numerous other AhR ligands have been described. In this study, we investigated the effect of three structurally different non-dioxin-like AhR ligands, e.g., 6-formylindolo[3,2-b]carbazole (FICZ), β-naphthoflavone (β-NF), and 6-methyl-1,3,8-trichlorodibenzofuran (6-MCDF), on peanut sensitization. Female C57BL/6 mice were sensitized by administering peanut extract (PE) by gavage in the presence of cholera toxin. Before and during peanut sensitization, mice were treated with FICZ, β-NF, or 6-MCDF. AhR gene transcription in duodenum and liver was investigated on day 5, even as the effect of these AhR ligands on CD4(+)CD25(+)Foxp3(+) T(reg) cells in spleen and mesenteric lymph nodes (MLNs). Mice treated with TCDD were included as a positive control. Furthermore, the murine reporter cell line H1G1.1c3 (CAFLUX) was used to investigate the possible role of metabolism of TCDD, FICZ, β-NF, and 6-MCDF on AhR activation in vitro. TCDD, but not FICZ, β-NF, and 6-MCDF, suppressed sensitization to peanut (measured by PE-specific IgE, IgG1, IgG2a and PE-induced interleukin (IL)-5, IL-10, IL-13, IL-17a, IL-22, and interferon-γ). In addition, FICZ, β-NF, and 6-MCDF treatments less effectively induced AhR gene transcription (measured by gene expression of AhR, AhRR, CYP1A1, CYP1A2, CYP1B1) compared with TCDD-treated mice. Furthermore, FICZ, β-NF and 6-MCDF did not increase the percentage of CD4(+)CD25(+)Foxp3(+) T(reg) cells in spleen and mesenteric lymph nodes compared with PE-sensitized mice, in contrast to TCDD. Inhibition of metabolism in vitro increased AhR activation. Together, these data shows that TCDD, but not FICZ, β-NF, and 6-MCDF suppresses sensitization to peanut. Differences in metabolism, AhR binding and subsequent gene transcription might explain these findings and warrant further studies to investigate the role of the AhR in food allergic responses.
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Affiliation(s)
- Veronica J Schulz
- Department of Toxicology, Institute for Risk Assessment Sciences, Utrecht University, 3508 TD Utrecht, The Netherlands
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Veiga-Parga T, Suryawanshi A, Rouse BT. Controlling viral immuno-inflammatory lesions by modulating aryl hydrocarbon receptor signaling. PLoS Pathog 2011; 7:e1002427. [PMID: 22174686 PMCID: PMC3234248 DOI: 10.1371/journal.ppat.1002427] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Accepted: 10/25/2011] [Indexed: 01/01/2023] Open
Abstract
Ocular herpes simplex virus infection can cause a blinding CD4⁺ T cell orchestrated immuno-inflammatory lesion in the cornea called Stromal Keratitis (SK). A key to controlling the severity of SK lesions is to suppress the activity of T cells that orchestrate lesions and enhance the representation of regulatory cells that inhibit effector cell function. In this report we show that a single administration of TCDD (2, 3, 7, 8- Tetrachlorodibenzo-p-dioxin), a non-physiological ligand for the AhR receptor, was an effective means of reducing the severity of SK lesions. It acted by causing apoptosis of Foxp3⁻ CD4⁺ T cells but had no effect on Foxp3⁺ CD4⁺ Tregs. TCDD also decreased the proliferation of Foxp3⁻ CD4⁺ T cells. The consequence was an increase in the ratio of Tregs to T effectors which likely accounted for the reduced inflammatory responses. In addition, in vitro studies revealed that TCDD addition to anti-CD3/CD28 stimulated naïve CD4⁺ T cells caused a significant induction of Tregs, but inhibited the differentiation of Th1 and Th17 cells. Since a single TCDD administration given after the disease process had been initiated generated long lasting anti-inflammatory effects, the approach holds promise as a therapeutic means of controlling virus induced inflammatory lesions.
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Affiliation(s)
- Tamara Veiga-Parga
- Department of Pathobiology, College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Amol Suryawanshi
- Emory Vaccine Center and Yerkes Primate Research Center, Atlanta, Georgia, United States of America
| | - Barry T. Rouse
- Department of Pathobiology, College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, United States of America
- * E-mail:
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Elizondo G, Rodríguez-Sosa M, Estrada-Muñiz E, Gonzalez FJ, Vega L. Deletion of the aryl hydrocarbon receptor enhances the inflammatory response to Leishmania major infection. Int J Biol Sci 2011; 7:1220-9. [PMID: 22110376 PMCID: PMC3221360 DOI: 10.7150/ijbs.7.1220] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 12/31/2022] Open
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated receptor that mediates the toxicity of environmental pollutants, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Recently, it has been shown that the AhR plays a role in immune and inflammatory regulation. However, most of these studies are based on the activation of AhR by exogenous ligands. Therefore, in the present study, we addressed the role of this transcription factor, in the absent of exogenous ligand, on the immune response to Leishmania major infection. Our results indicate that inactivation of the AhR results in an alteration of the levels of several cytokines. Lymph node cells from infected Ahr-null animals displayed an increase in IFNγ and IL-12 levels, together with a decrease in IL-4 and IL-10 levels compared to wild-type (wt) mice. Ahr-null mice also presented higher serum levels of the pro-inflammatory cytokine TNF-α prior to parasite inoculation and during infection compared to wt mice. Moreover, a 30% decrease in the population of Treg cells was observed in Ahr-null mice. This decrease was associated with a reduction in Foxp3 mRNA levels. Finally, the alteration in the cytokine profile results in a better resolution of the L. major infection.
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Affiliation(s)
- Guillermo Elizondo
- Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Departamento de Biología Celular, Av. IPN 2508, San Pedro Zacatenco, C. P. 07360, México D. F., México
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Greb-Markiewicz B, Orłowski M, Dobrucki J, Ożyhar A. Sequences that direct subcellular traffic of the Drosophila methoprene-tolerant protein (MET) are located predominantly in the PAS domains. Mol Cell Endocrinol 2011; 345:16-26. [PMID: 21745535 DOI: 10.1016/j.mce.2011.06.035] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 06/02/2011] [Accepted: 06/28/2011] [Indexed: 11/25/2022]
Abstract
Methoprene-tolerant protein (MET) is a key mediator of antimetamorphic signaling in insects. MET belongs to the family of bHLH-PAS transcription factors which regulate gene expression and determine essential physiological and developmental processes. The ability of many bHLH-PAS proteins to carry out their functions is related to the patterns of intracellular trafficking, which are determined by specific sequences and indicate that a nuclear localization signal (NLS) or a nuclear export signal (NES) is present and active. Therefore, the identification of NLS and NES signals is fundamental in order to understand the intracellular signaling role of MET. Nevertheless, data on the intracellular trafficking of MET are inconsistent, and until now there hasn't been any data on potential NLS and NES sequences. To analyze the trafficking of MET we designed a number of expression vectors encoding full-length MET, as well as various derivatives, that were fused to yellow fluorescent protein (YFP). Confocal microscopy analysis of the subcellular distribution of YFP-MET indicated that while this protein was localized mainly in the nucleus, it was also observed in the cytoplasm. This suggested the presence of both an NLS and NES in MET. Our work has shown that each of the two PAS domains of MET (PAS-A and PAS-B, respectively) contain one NLS and one NES sequence. Additional NES activity was present in the C-terminal fragment. The NLS activity located in PAS-B was dependent on the presence of juvenile hormone (JH), the potential ligand for MET. In contrast to this, JH didn't seem to be required for the NLS in PAS-A to be active. However, on the basis of current knowledge about the function of PAS-A in other bHLH-PAS proteins, we suggest there might be other proteins that control the activity of the NLS and possibly the NES located in the PAS-A of MET. Thus, the intracellular trafficking of MET seems to be regulated by a rather complicated network of different factors.
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Affiliation(s)
- Beata Greb-Markiewicz
- Department of Biochemistry, Faculty of Chemistry, Wrocław University of Technology, Poland.
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Dvorak Z, Pavek P. Regulation of drug-metabolizing cytochrome P450 enzymes by glucocorticoids. Drug Metab Rev 2011; 42:621-35. [PMID: 20482443 DOI: 10.3109/03602532.2010.484462] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The regulation of drug-metabolizing cytochrome P450 enzymes (CYP) is a complex process involving multiple mechanisms. Among them, transcriptional regulation through ligand-activated nuclear receptors is the crucial mechanism involved in hormone-controlled and xenobiotic-induced expression of drug-metabolizing CYPs. In this article, we focus, in detail, on the role of the glucocorticoid receptor (GR) in the transcriptional regulation of human drug-metabolizing CYP enzymes and the mechanisms of the regulation. There are at least three distinct transcriptional mechanisms by which GR controls the expression of CYPs: 1) direct binding of GR to a specific gene-promoter sequence called the glucocorticoid responsive element (GRE); 2) indirect binding of GR in the form of a multiprotein complex to gene promoters without a direct contact between GR and promoter DNA; and 3) up- or downregulation of other CYP transcriptional regulators or nuclear receptors (i.e., transcriptional regulatory cross-talk). However, due to the general effect of glucocorticoids on numerous cellular pathways and functions, the net transcriptional effect of glucocorticoids on drug-metabolizing enzymes is usually a combination of several mechanisms. Since synthetic glucocorticoids are widely prescribed in human pharmacotherapy for the treatment of many diseases, comprehensive understanding of the transcriptional regulation of drug-metabolizing CYPs via GR with respect to glucocorticoid therapy or glucocorticoid hormonal status will aid in the development of efficient individualized pharmacotherapy without drug-drug interactions.
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Affiliation(s)
- Zdenek Dvorak
- Department of Cell Biology and Genetics, Faculty of Science, Palacky University, Olomouc, Czech Republic.
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Veldhoen M, Duarte JH. The aryl hydrocarbon receptor: fine-tuning the immune-response. Curr Opin Immunol 2011; 22:747-52. [PMID: 20926270 DOI: 10.1016/j.coi.2010.09.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 08/26/2010] [Accepted: 09/07/2010] [Indexed: 11/26/2022]
Abstract
Triggers involved in the development of an autoimmune disease, and those that are part of determining its level of severity, are a major focus of current investigative efforts. However, factors that increase the risk to disease may not be similar to those that determine its severity or its pace of progression. The aryl hydrocarbon receptor (AhR) has been highlighted as having a potential regulatory role in these processes. Here we describe the recent findings of the possible involvement of AhR in the initiation and inhibition of immune responses.
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Affiliation(s)
- Marc Veldhoen
- Laboratory of Lymphocyte Signalling and Development, The Babraham Institute, Cambridge, CB22 3AT, UK.
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42
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External influences on the immune system via activation of the aryl hydrocarbon receptor. Semin Immunol 2011; 23:99-105. [PMID: 21288737 DOI: 10.1016/j.smim.2011.01.008] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 01/10/2011] [Indexed: 02/06/2023]
Abstract
The aryl hydrocarbon receptor (AhR), subject of intensive research over three decades by the pharmacology/toxicology field has recently made its entry into mainstream immunology research and is set to continue to intrigue with ever more complex modes of modulating immune responses. The discovery of high and selective AhR expression on Th17 cells and its role in induction of the cytokine IL-22 attributed new immunological functions to this transcription factor and stimulated further research into physiological functions of the AhR in the immune system. A number of recent reviews have highlighted potential new avenues of research. This review addresses recent new insight into physiological roles of AhR in the immune system.
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Apetoh L, Quintana FJ, Pot C, Joller N, Xiao S, Kumar D, Burns EJ, Sherr DH, Weiner HL, Kuchroo VK. The aryl hydrocarbon receptor interacts with c-Maf to promote the differentiation of type 1 regulatory T cells induced by IL-27. Nat Immunol 2010; 11:854-61. [PMID: 20676095 PMCID: PMC2940320 DOI: 10.1038/ni.1912] [Citation(s) in RCA: 584] [Impact Index Per Article: 41.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 07/01/2010] [Indexed: 02/07/2023]
Abstract
Type 1 regulatory T cells (Tr1 cells ) that produce interleukin 10 (IL-10) are instrumental in the prevention of tissue inflammation, autoimmunity and graft-versus-host disease. The transcription factor c-Maf is essential for the induction of IL-10 by Tr1 cells, but the molecular mechanisms that lead to the development of these cells remain unclear. Here we show that the ligand-activated transcription factor aryl hydrocarbon receptor (AhR), which was induced by IL-27, acted in synergy with c-Maf to promote the development of Tr1 cells. After T cell activation under Tr1-skewing conditions, the AhR bound to c-Maf and promoted transactivation of the Il10 and Il21 promoters, which resulted in the generation of Tr1 cells and the amelioration of experimental autoimmune encephalomyelitis. Manipulating AhR signaling could therefore be beneficial in the resolution of excessive inflammatory responses.
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Affiliation(s)
- Lionel Apetoh
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Francisco J. Quintana
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Caroline Pot
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Nicole Joller
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Sheng Xiao
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Deepak Kumar
- Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston 02115, MA, USA
| | - Evan J. Burns
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - David H. Sherr
- Department of Environmental Health, Boston University School of Public Health, Boston, MA 02118, United States
| | - Howard L. Weiner
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
| | - Vijay K. Kuchroo
- Center for Neurologic Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, United States
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Perinatal bisphenol A exposure in C57B6/129svj male mice: potential altered cytokine/chemokine production in adulthood. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2010; 7:2845-52. [PMID: 20717544 PMCID: PMC2922731 DOI: 10.3390/ijerph7072845] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 07/09/2010] [Indexed: 01/29/2023]
Abstract
Pregnant mice (n = 3) were exposed to BPA by intraperitoneal injection, from gestation day 9.5 until end of lactation. Male offspring were evaluated for cytokine production at 20 wk-of-age. One pregnant control mouse produced no males, precluding statistical analysis. However, recurring shifts in cytokines were suggested in the adult BPA offspring. Serum showed a numeric increase in 16 of 21 basal cytokine levels. ConA-stimulated splenocytes showed a numeric increase in 17 of 21 cytokines, and LPS-stimulated splenocytes an increase in 18 of 21 cytokines. The cytokine profile was one of T(H)1 up-regulation more than T(H)2, and with skewing toward T(H)17 responses.
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Ulrich K, Wölfle S, Mayer A, Heeg K, Braunbeck T, Erdinger L, Bartz H. Extractable organic matter of standard reference material 1649a influences immunological response induced by pathogen-associated molecular patterns. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2010; 17:1257-1267. [PMID: 20195909 DOI: 10.1007/s11356-010-0305-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 01/29/2010] [Indexed: 05/28/2023]
Abstract
BACKGROUND, AIM, AND SCOPE Lungs are permanently and simultaneously challenged by airborne microorganisms and airborne pollutants. Temporal increase of airborne particulate matter (APM), a potential carrier for extractable organic matter (EOM), degrades the situation of pulmonary patients. The Ah receptor (AhR) has been described as an important factor influencing the immunological challenge by viral infections. Molecular mechanisms underlying epidemiological observations are not well understood. Cytokine secretion (IL-6, IL-8, and TGF-beta) from human bronchial epithelial cells (Beas2B) was determined as an indicator for immune responses upon co-stimulation with an artificial analog of viral dsRNA [polyinosinic/polycytidylic acid, (PIC)] and EOM of Standard Reference Material 1649a (SRM). Since polycyclic aromatic hydrocarbons are major components of APM usually acting via the AhR, particular focus was on AhR involvement. MATERIALS AND METHODS Cytokine secretion was demonstrated by enzyme-linked immunosorbent assay. To mimic the activation of organic matter during contact of particles with the human lung, Soxhlet extraction of SRM was performed. In some experiments, the AhR was blocked by alpha-naphthoflavone. RESULTS Microbial stimulation (PIC) induced Beas2B cytokine release, whereas isolated exposure to EOM of APM did not. Co-stimulation with EOM and PIC increased IL-8 secretion, whereas neither IL-6 nor TGF-beta was affected. Blocking of the AhR suppressed the release of IL-8. DISCUSSION Organic compounds adsorbed on airborne particulate matter influence the cytokine secretion of lung epithelial cells induced by pathogen-associated molecular patterns. RECOMMENDATIONS AND PERSPECTIVES Further investigation of these observations is required to understand the molecular mechanisms underlying adverse health effects of APM reported in epidemiological studies.
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Affiliation(s)
- Kerstin Ulrich
- Aquatic Ecology and Toxicology Group, Department of Zoology, University of Heidelberg, Im Neuenheimer Feld 230, 69120, Heidelberg, Germany.
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Schlezinger JJ, Bernard PL, Haas A, Grandjean P, Weihe P, Sherr DH. Direct assessment of cumulative aryl hydrocarbon receptor agonist activity in sera from experimentally exposed mice and environmentally exposed humans. ENVIRONMENTAL HEALTH PERSPECTIVES 2010; 118:693-698. [PMID: 20435556 PMCID: PMC2866687 DOI: 10.1289/ehp.0901113] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Accepted: 12/14/2009] [Indexed: 05/29/2023]
Abstract
BACKGROUND Aryl hydrocarbon receptor (AhR) ligands adversely affect many biological processes. However, assessment of the significance of human exposures is hampered by an incomplete understanding of how complex mixtures affect AhR activation/inactivation. OBJECTIVES These studies used biological readouts to provide a broader context for estimating human risk than that obtained with serum extraction and gas chromatography/mass spectroscopy (GC/MS)-based assays alone. METHODS AhR agonist activity was quantified in sera from dioxin-treated mice, commercial human sources, and polychlorinated biphenyl (PCB)-exposed Faroe Islanders using an AhR-driven reporter cell line. To validate relationships between serum AhR agonist levels and biological outcomes, AhR agonist activity in mouse sera correlated with toxic end points. AhR agonist activity in unmanipulated ("neat") human sera was compared with these biologically relevant doses and with GC/MS-assayed PCB levels. RESULTS Mouse serum AhR agonist activity correlated with injected dioxin dose, thymic atrophy, and heptomegaly, validating the use of neat serum to assess AhR agonist activity. AhR agonist activity in sera from Faroe Islanders varied widely, was associated with the frequency of recent pilot whale dinners, but did not correlate with levels of PCBs quantified by GC/MS. Surprisingly, significant "baseline" AhR activity was found in commercial human sera. CONCLUSIONS An AhR reporter assay revealed cumulative levels of AhR activation potential in neat serum, whereas extraction may preclude detection of important non-dioxin-like biological activity. Significant levels of AhR agonist activity in commercial sera and in Faroe Islander sera, compared with that from experimentally exposed mice, suggest human exposures that are biologically relevant in both populations.
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Affiliation(s)
- Jennifer J Schlezinger
- Department of Environmental Health, Boston University School of Public Health, Boston, Massachusetts 02118 , USA.
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Dietert RR, Zelikoff JT. Identifying patterns of immune-related disease: use in disease prevention and management. World J Pediatr 2010; 6:111-8. [PMID: 20490766 DOI: 10.1007/s12519-010-0026-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2008] [Accepted: 08/23/2009] [Indexed: 12/20/2022]
Abstract
BACKGROUND Childhood susceptibility to diseases linked with immune dysfunction affects over a quarter of the pediatric population in some countries. While this alone is a significant health issue, the actual impact of immune-related diseases extends over a lifetime and involves additional secondary conditions. Some comorbidities are well known (e.g., allergic rhinitis and asthma). However, no systematic approach has been used to identify life-long patterns of immune-based disease where the primary condition arises in childhood. Such information is useful for both disease prevention and treatment approaches. DATA SOURCES Recent primary research papers as well as review articles were obtained from PubMed, Chem Abstracts, Biosis and from the personal files of the authors. Search words used were: the diseases and conditions shown Figs. 1 and 2 in conjunction with comorbid, comorbidities, pediatric, childhood, adult, immune, immune dysfunction, allergy, autoimmune, inflammatory, infectious, health risks, environment, risk factors. RESULTS Childhood diseases such as asthma, type-1 diabetes, inflammatory bowel disease, respiratory infections /rhinitis, recurrent otitis media, pediatric celiac, juvenile arthritis and Kawasaki disease are examples of significant childhood health problems where immune dysfunction plays a significant role. Each of these pediatric diseases is associated with increased risk of several secondary conditions, many of which appear only later in life. To illustrate, four prototypes of immune-related disease patterns (i.e., allergy, autoimmunity, inflammation and infectious disease) are shown as tools for: 1) enhanced disease prevention; 2) improved management of immune-based pediatric diseases; and 3) better recognition of underlying pediatric immune dysfunction. CONCLUSIONS Identification of immune-related disease patterns beginning in childhood provides the framework for examining the underlying immune dysfunctions that can contribute to additional diseases in later life. Many pediatric diseases associated with dysfunctional immune responses have been linked with an elevated risk of other diseases or conditions as the child ages. Diseases within a pattern may be interlinked based on underlying immune dysfunctions and/or current therapeutic approaches for managing the entryway diseases. It may be beneficial to consider treatment options for the earliest presenting diseases that will concomitantly reduce the risk of immune-linked secondary conditions. Additionally, improved disease prevention is possible with more relevant and age-specific immune safety testing.
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Affiliation(s)
- Rodney R Dietert
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, 14853, USA.
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Marshall NB, Kerkvliet NI. Dioxin and immune regulation: emerging role of aryl hydrocarbon receptor in the generation of regulatory T cells. Ann N Y Acad Sci 2010; 1183:25-37. [PMID: 20146706 DOI: 10.1111/j.1749-6632.2009.05125.x] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The immune toxicity of the ubiquitous environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), commonly referred to as dioxin, has been studied for over 35 years but only recently has the profound immune suppression induced by TCDD exposure been linked to induction of regulatory T cells (Tregs). The effects of TCDD are mediated through its binding to the aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor. The subsequent AHR-dependent effects on immune responses are determined by the cell types involved, their activation status, and the type of antigenic stimulus. Collectively, studies indicate that TCDD inhibits CD4+ T cell differentiation into T helper (Th)1, Th2, and Th17 effector cells, while inducing Foxp3-negative and/or preserving Foxp3+ Tregs. Although it is not yet clear how activation of AHR by TCDD induces Tregs, there is a potential therapeutic role for alternative AHR ligands in the treatment of immune-mediated disorders.
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Affiliation(s)
- Nikki B Marshall
- Department of Microbiology, Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97331, USA
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Abstract
A foremost objective of preclinical immunotoxicity testing is to address whether or not a drug or environmental toxicant causes adverse effects on net immune health, expressly the host's ability to mount an appropriate immune response to clear infectious organisms. Given the complex interactions, diverse molecular signaling events, and redundancies of immunity that has itself been subdivided into interdependent arms, namely innate, adaptive, and humoral, the results of single immune parameter testing may not reflect the final outcome of a drug or toxicant's effect on net immune health. The most comprehensive experimental approach to ascertain this information is utilization of host resistance models. Herein, application of viral host resistance models in rodents and non-human primates is described. Although brief descriptions of numerous viral models are discussed including reovirus, Epstein-Barr virus, cytomegalovirus, and lymphocryptovirus, the most well-characterized viral host resistance model, rodent influenza, is emphasized.
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Gasiewicz TA, Singh KP, Casado FL. The aryl hydrocarbon receptor has an important role in the regulation of hematopoiesis: implications for benzene-induced hematopoietic toxicity. Chem Biol Interact 2009; 184:246-51. [PMID: 19896476 DOI: 10.1016/j.cbi.2009.10.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 10/22/2009] [Accepted: 10/24/2009] [Indexed: 10/20/2022]
Abstract
The aryl hydrocarbon receptor (AhR) belongs to the basic helix-loop-helix (bHLH) Per-Arnt-Sim (PAS) family of transcription factors. Many of these proteins are involved in regulating responses to signals in the tissue environment such as hypoxia, oxidation-reduction status, and circadian rhythms. Although the AhR is well studied as a mediator of the toxicity of certain xenobiotics, the normal physiological function remains unknown. However, accumulating data support a hypothesis that the AhR has an important function in the regulation of hematopoietic stem cells (HSCs). Persistent AhR activation by dioxin, a potent xenobiotic AhR agonist, results in altered numbers and function of HSCs in mouse bone marrow. Analysis of HSCs from AhR null-allele mice also indicates that lack of AhR expression results in altered characteristics and function of these cells. HSCs from these animals are hyperproliferative and have altered cell cycle. In addition, aging AhR-KO mice show characteristics consistent with premature bone marrow senescence and are prone to hematopoietic disease. Finally, some data suggest that the expression of the Ahr gene is regulated under conditions that control HSC proliferation. The presence of a normal functioning AhR may provide an important advantage to organisms by regulating the balance between quiescence and proliferation and preventing the premature exhaustion of HSCs and sensitivity to genetic alterations. This function assists in the preservation of HSC function and long-term multi-lineage generation over the lifespan of the organism. This also implicates a role for the AhR in the aging process. Furthermore, these functions may affect the sensitivity of HSCs to certain xenobiotics, including benzene. Defining the molecular mechanisms by which these events occur may lead to the identification of previously undefined roles of this transcription factor in human diseases, particularly those caused or affected by xenobiotics.
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Affiliation(s)
- Thomas A Gasiewicz
- Department of Environmental Medicine, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA.
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