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Simmons SR, Herring SE, Tchalla EYI, Lenhard AP, Bhalla M, Bou Ghanem EN. Activating A1 adenosine receptor signaling boosts early pulmonary neutrophil recruitment in aged mice in response to Streptococcus pneumoniae infection. Immun Ageing 2024; 21:34. [PMID: 38840213 PMCID: PMC11151497 DOI: 10.1186/s12979-024-00442-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Accepted: 05/29/2024] [Indexed: 06/07/2024]
Abstract
BACKGROUND Streptococcus pneumoniae (pneumococcus) is a leading cause of pneumonia in older adults. Successful control of pneumococci requires robust pulmonary neutrophil influx early in infection. However, aging is associated with aberrant neutrophil recruitment and the mechanisms behind that are not understood. Here we explored how neutrophil recruitment following pneumococcal infection changes with age and the host pathways regulating this. RESULTS Following pneumococcal infection there was a significant delay in early neutrophil recruitment to the lungs of aged mice. Neutrophils from aged mice showed defects in trans-endothelial migration in vitro compared to young controls. To understand the pathways involved, we examined immune modulatory extracellular adenosine (EAD) signaling, that is activated upon cellular damage. Signaling through the lower affinity A2A and A2B adenosine receptors had no effect on neutrophil recruitment to infected lungs. In contrast, inhibition of the high affinity A1 receptor in young mice blunted neutrophil recruitment to the lungs following infection. A1 receptor inhibition decreased expression of CXCR2 on circulating neutrophils, which is required for trans-endothelial migration. Indeed, A1 receptor signaling on neutrophils was required for their ability to migrate across endothelial cells in response to infection. Aging was not associated with defects in EAD production or receptor expression on neutrophils. However, agonism of A1 receptor in aged mice rescued the early defect in neutrophil migration to the lungs and improved control of bacterial burden. CONCLUSIONS This study suggests age-driven defects in EAD damage signaling can be targeted to rescue the delay in pulmonary neutrophil migration in response to bacterial pneumonia.
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Affiliation(s)
- Shaunna R Simmons
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Sydney E Herring
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Essi Y I Tchalla
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Alexsandra P Lenhard
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Manmeet Bhalla
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA
| | - Elsa N Bou Ghanem
- Department of Microbiology and Immunology, School of Medicine, University at Buffalo, Buffalo, NY, USA.
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Simmons SR, Herring SE, Tchalla EYI, Lenhard AP, Bhalla M, Bou Ghanem EN. Activating A1 adenosine receptor signaling boosts early pulmonary neutrophil recruitment in aged mice in response to Streptococcus pneumoniae infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574741. [PMID: 38260350 PMCID: PMC10802397 DOI: 10.1101/2024.01.08.574741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Background Streptococcus pneumoniae (pneumococcus) is a leading cause of pneumonia in older adults. Successful control of pneumococci requires robust pulmonary neutrophil influx early in infection. However, aging is associated with aberrant neutrophil recruitment and the mechanisms behind that are not understood. Here we explored how neutrophil recruitment following pneumococcal infection changes with age and the host pathways regulating this. Results Following pneumococcal infection there was a significant delay in early neutrophil recruitment to the lungs of aged mice. Neutrophils from aged mice showed defects in trans-endothelial migration in vitro compared to young controls. To understand the pathways involved, we examined immune modulatory extracellular adenosine (EAD) signaling, that is activated upon cellular damage. Signaling through the lower affinity A2A and A2B adenosine receptors had no effect on neutrophil recruitment to infected lungs. In contrast, inhibition of the high affinity A1 receptor in young mice blunted neutrophil recruitment to the lungs following infection. A1 receptor inhibition decreased expression of CXCR2 on circulating neutrophils, which is required for transendothelial migration. Indeed, A1 receptor signaling on neutrophils was required for their ability to migrate across endothelial cells in response to infection. Aging was not associated with defects in EAD production or receptor expression on neutrophils. However, agonism of A1 receptor in aged mice rescued the early defect in neutrophil migration to the lungs and improved control of bacterial burden. Conclusions This study suggests age-driven defects in EAD damage signaling can be targeted to rescue the delay in pulmonary neutrophil migration in response to bacterial pneumonia.
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Tao X, Zhang J, Meng Q, Chu J, Zhao R, Liu Y, Dong Y, Xu H, Tian T, Cui J, Zhang L, Chu M. The potential health effects associated with electronic-cigarette. ENVIRONMENTAL RESEARCH 2024; 245:118056. [PMID: 38157958 DOI: 10.1016/j.envres.2023.118056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 12/17/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
A good old gateway theory that electronic-cigarettes (e-cigarettes) are widely recognized as safer tobacco substitutes. In actuality, demographics also show that vaping cannibalizes smoking, the best explanation of the data is the "common liability". However, the utilization of e-cigarette products remains a controversial topic at present. Currently, there has been a widespread and substantial growth in e-cigarette use worldwide owing to their endless new flavors and customizable characteristics. Furthermore, e-cigarette has grown widespread among smokers as well as non-smokers, including adolescents and young adults. And some studies have shown that e-cigarette users are at greater risk to start using combustible cigarettes while e-cigarettes use was also observed the potential benefits to people who want to quit smoking or not. Although it is true that e-cigarettes generally contain fewer toxic substances than combustible cigarettes, this does not mean that the chemical composition in e-cigarettes aerosols poses absolutely no risks. While concerns about toxic substances in e-cigarettes and their widespread use in the population are reasonable, it is also crucial to consider that e-cigarettes have been associated with the potential for promoting smoking cessation and the clinically relevant improvements in users with smoking-related pathologies. Meanwhile, there is still short of understanding of the health impacts associated with e-cigarette use. Therefore, in this review, we discussed the health impacts of e-cigarette exposure on oral, nasal, pulmonary, cardiovascular systems and brain. We aspire for this review to change people's previous perceptions of e-cigarettes and provide them with a more balanced perspective. Additionally, we suggest appropriate adjustments on regulation and policy for e-cigarette to gain greater public health benefits.
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Affiliation(s)
- Xiaobo Tao
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Jiale Zhang
- The Second People's Hospital of Nantong, Nantong, Jiangsu, China
| | - Qianyao Meng
- Department of Global Health and Population, School of Public Health, Harvard University, Boston, USA
| | - Junfeng Chu
- Department of Oncology, Jiangdu People's Hospital of Yangzhou, Yangzhou, Jiangsu, China
| | - Rongrong Zhao
- Department of Oncology, Jiangdu People's Hospital of Yangzhou, Yangzhou, Jiangsu, China
| | - Yiran Liu
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Yang Dong
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Huiwen Xu
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Tian Tian
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Jiahua Cui
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China
| | - Lei Zhang
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China.
| | - Minjie Chu
- Department of Epidemiology, School of Public Health, Nantong University, Nantong, Jiangsu, China.
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Wang H, Su Y, Chen D, Li Q, Shi S, Huang X, Fang M, Yang M. Advances in the mechanisms and applications of inhibitory oligodeoxynucleotides against immune-mediated inflammatory diseases. Front Pharmacol 2023; 14:1119431. [PMID: 36825156 PMCID: PMC9941346 DOI: 10.3389/fphar.2023.1119431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/26/2023] [Indexed: 02/09/2023] Open
Abstract
Inhibitory oligodeoxynucleotides (ODNs) are short single-stranded DNA, which capable of folding into complex structures, enabling them to bind to a large variety of targets. With appropriate modifications, the inhibitory oligodeoxynucleotides exhibited many features of long half-life time, simple production, low toxicity and immunogenicity. In recent years, inhibitory oligodeoxynucleotides have received considerable attention for their potential therapeutic applications in immune-mediated inflammatory diseases (IMIDs). Inhibitory oligodeoxynucleotides could be divided into three categories according to its mechanisms and targets, including antisense ODNs (AS-ODNs), DNA aptamers and immunosuppressive ODNs (iSup ODNs). As a synthetic tool with immunomodulatory activity, it can target RNAs or proteins in a specific way, resulting in the reduction, increase or recovery of protein expression, and then regulate the state of immune activation. More importantly, inhibitory oligodeoxynucleotides have been used to treat immune-mediated inflammatory diseases, including inflammatory disorders and autoimmune diseases. Several inhibitory oligodeoxynucleotide drugs have been developed and approved on the market already. These drugs vary in their chemical structures, action mechanisms and cellular targets, but all of them could be capable of inhibiting excessive inflammatory responses. This review summarized their chemical modifications, action mechanisms and applications of the three kinds of inhibitory oligodeoxynucleotidesin the precise treatment of immune-mediated inflammatory diseases.
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Affiliation(s)
- Hongrui Wang
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Yingying Su
- Department of Anatomy, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Duoduo Chen
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Qi Li
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Shuyou Shi
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Xin Huang
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China
| | - Mingli Fang
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China,*Correspondence: Mingli Fang, ; Ming Yang,
| | - Ming Yang
- Department of Molecular Biology, College of Basic Medical Sciences, Jilin University, Changchun, Jilin, China,*Correspondence: Mingli Fang, ; Ming Yang,
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Mitochondrial ROS production by neutrophils is required for host antimicrobial function against Streptococcus pneumoniae and is controlled by A2B adenosine receptor signaling. PLoS Pathog 2022; 18:e1010700. [DOI: 10.1371/journal.ppat.1010700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 11/28/2022] [Accepted: 11/07/2022] [Indexed: 11/15/2022] Open
Abstract
Polymorphonuclear cells (PMNs) control Streptococcus pneumoniae (pneumococcus) infection through various antimicrobial activities. We previously found that reactive oxygen species (ROS) were required for optimal antibacterial function, however, the NADPH oxidase is known to be dispensable for the ability of PMNs to kill pneumococci. In this study, we explored the role of ROS produced by the mitochondria in PMN antimicrobial defense against pneumococci. We found that the mitochondria are an important source of overall intracellular ROS produced by murine PMNs in response to infection. We investigated the host and bacterial factors involved and found that mitochondrial ROS (MitROS) are produced independent of bacterial capsule or pneumolysin but presence of live bacteria that are in direct contact with PMNs enhanced the response. We further found that MyD88-/- PMNs produced less MitROS in response to pneumococcal infection suggesting that released bacterial products acting as TLR ligands are sufficient for inducing MitROS production in PMNs. To test the role of MitROS in PMN function, we used an opsonophagocytic killing assay and found that MitROS were required for the ability of PMNs to kill pneumococci. We then investigated the role of MitROS in host resistance and found that MitROS are produced by PMNs in response to pneumococcal infection. Importantly, treatment of mice with a MitROS scavenger prior to systemic challenge resulted in reduced survival of infected hosts. In exploring host pathways that control MitROS, we focused on extracellular adenosine, which is known to control PMN anti-pneumococcal activity, and found that signaling through the A2B adenosine receptor inhibits MitROS production by PMNs. A2BR-/- mice produced more MitROS and were significantly more resistant to infection. Finally, we verified the clinical relevance of our findings using human PMNs. In summary, we identified a novel pathway that controls MitROS production by PMNs, shaping host resistance against S. pneumoniae.
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Urso A, Prince A. Anti-Inflammatory Metabolites in the Pathogenesis of Bacterial Infection. Front Cell Infect Microbiol 2022; 12:925746. [PMID: 35782110 PMCID: PMC9240774 DOI: 10.3389/fcimb.2022.925746] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 05/23/2022] [Indexed: 01/13/2023] Open
Abstract
Host and pathogen metabolism have a major impact on the outcome of infection. The microenvironment consisting of immune and stromal cells drives bacterial proliferation and adaptation, while also shaping the activity of the immune system. The abundant metabolites itaconate and adenosine are classified as anti-inflammatory, as they help to contain the local damage associated with inflammation, oxidants and proteases. A growing literature details the many roles of these immunometabolites in the pathogenesis of infection and their diverse functions in specific tissues. Some bacteria, notably P. aeruginosa, actively metabolize these compounds, others, such as S. aureus respond by altering their own metabolic programs selecting for optimal fitness. For most of the model systems studied to date, these immunometabolites promote a milieu of tolerance, limiting local immune clearance mechanisms, along with promoting bacterial adaptation. The generation of metabolites such as adenosine and itaconate can be host protective. In the setting of acute inflammation, these compounds also represent potential therapeutic targets to prevent infection.
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Affiliation(s)
| | - Alice Prince
- *Correspondence: Alice Prince, ; Andreacarola Urso,
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Miyashita L, Shears R, Foley G, Semple S, Kadioglu A, Grigg J. Underground railway particulate matter and susceptibility to pneumococcal infection. EBioMedicine 2022; 80:104063. [PMID: 35598440 PMCID: PMC9127572 DOI: 10.1016/j.ebiom.2022.104063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/26/2022] [Accepted: 04/30/2022] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Concentrations of particulate matter less than 10 microns (PM10) on underground railways are higher than those near urban roads. Traffic-related PM10 increases pneumococcal infection via increasing the expression of platelet-activating factor receptor (PAFR), a receptor co-opted by pneumococci to adhere to cells. To date, it is unknown whether underground railway PM10 increases pneumococcal infection. This study sought to determine the effect of London Underground (LU) PM10 on; i) pneumococcal adhesion to airway cells, and ii) susceptibility to pneumococcal disease. METHODS A549 cells and human primary airway epithelial cells were cultured with 20 µg/mL PM10 from the Bakerloo (B-PM10) and Jubilee (J-PM10) line platforms of Baker Street station. PAFR expression was assessed by flow cytometry, and pneumococcal adhesion by colony forming unit (CFU) counts. Traffic-related PM10 was collected next to a main road near the station's entrance. The PAFR blocker CV3988 and the antioxidant N-acetyl cysteine were used to assess the role of PAFR-mediated pneumococcal adhesion and oxidative stress respectively. Pneumococcal infection of mice was done after exposure to 3×80 μg doses of intranasal LU-PM10. FINDINGS In A549 cells, human primary nasal cells, and human primary bronchial epithelial cells, B-PM10 and J-PM10 increased PAFR expression and pneumococcal adhesion. Stimulated adhesion was abrogated by CV3988 and N-acetyl cysteine. Traffic-related PM10 stimulated increased adhesion compared with B-PM10. B-PM10 and J-PM10 increased lung and blood CFU and mortality in mice. Treatment of B-PM10-exposed mice with CV3988 reduced blood CFU. INTERPRETATION LU-PM10 increases pneumococcal adhesion to airway cells and susceptibility to invasive disease in mice. FUNDING The Medical College of Saint Bartholomew's Hospital Trust, and the UK Medical Research Council Programme Grant (MR/P011284/1).
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Affiliation(s)
- Lisa Miyashita
- Centre for Genomics and Child Health, Blizard Institute, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK
| | - Rebecca Shears
- The Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, UK
| | - Gary Foley
- Centre for Genomics and Child Health, Blizard Institute, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK
| | - Sean Semple
- Institute for Social Marketing and Health, University of Stirling, Scotland
| | - Aras Kadioglu
- The Department of Clinical Infection, Microbiology and Immunology, University of Liverpool, Liverpool, UK
| | - Jonathan Grigg
- Centre for Genomics and Child Health, Blizard Institute, Queen Mary University of London, 4 Newark Street, London E1 2AT, UK.
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Abdulhameed Nuri Shamsa R, Ali Al-Dahhan HA. Correlation of COVID-19 Receptors with Neutrophils and Their Role in the Adherence of Co-Infected Bacteria. ARCHIVES OF RAZI INSTITUTE 2022; 77:779-784. [PMID: 36284965 PMCID: PMC9548267 DOI: 10.22092/ari.2022.356974.1951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 01/16/2022] [Indexed: 05/24/2023]
Abstract
The COVID-19 caused by the SARS-CoV-2 virus has an impact on all aspects of patient care. Since the onset of this disease pandemic in 2019, numerous studies have been published which have attempted to identify virus receptors in the upper respiratory tract, such as nasal, oropharynx, and lung and their role in coinfection of bacterial adherence. In this study, the level of m RNA for platelet-activating factor receptor (PAF-R) and angiotensin-converting enzyme 2 receptor (ACE2-R) were detected in the whole blood of COVID-19 patients and controlled by using real-time reverse transcription-polymerase chain reaction technique. The results of the expression level of the PAF-R gene were higher in patients (43 ± 12.5) than in the healthy control (40 ± 2.1). Moreover, the expression level of ACE2-R was significantly (0.0001) increased in patients (27.5±6.2), compared to the control group. In addition, there was an elevation of neutrophils (79.6±17.6%) and PAF-R level (43%) in COVID-19 patients in comparison to the control (40) with a positive correlation between these factors (r=0.8769, P=0.0001). Nasopharyngeal epithelial cells showed a higher adherence rate (86%) to both bacteria isolates (Streptococcus pneumonia and Staphylococcus aureus) in patients than in the control group. Increased expression of PAF-R and ACE2-R genes in COVID-19 patients and co-infected bacteria disease could be the factors for the SARS-CoV-2 virus to enter the cells of the host.
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Affiliation(s)
| | - H A Ali Al-Dahhan
- Laboratory Investigation Department, Faculty of Science, University of Kufa, Kufa, Iraq
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Eberhardt N, Bergero G, Mazzocco Mariotta YL, Aoki MP. Purinergic modulation of the immune response to infections. Purinergic Signal 2022; 18:93-113. [PMID: 34997903 PMCID: PMC8742569 DOI: 10.1007/s11302-021-09838-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/17/2021] [Indexed: 02/07/2023] Open
Abstract
Infectious diseases are caused by the invasion of pathogenic microorganisms such as fungi, bacteria, viruses, and parasites. After infection, disease progression relies on the complex interplay between the host immune response and the microorganism evasion strategies. The host's survival depends on its ability to mount an efficient protective anti-microbial response to accomplish pathogen clearance while simultaneously preventing tissue injury by keeping under control the excessive inflammatory process. The purinergic system has the dual function of regulating the immune response and triggering effector antimicrobial mechanisms. This review provides an overview of the current knowledge of the modulation of innate and adaptive immunity driven by the purinergic system during parasitic, bacterial and viral infections.
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Affiliation(s)
- Natalia Eberhardt
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET) - Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Present Address: Department of Medicine, Leon H. Charney Division of Cardiology, New York University School of Medicine, New York, USA
| | - Gastón Bergero
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET) - Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - Yanina L. Mazzocco Mariotta
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET) - Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - M. Pilar Aoki
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Tecnológicas (CONICET) - Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
- Haya de La Torre and Medina Allende, Ciudad Universitaria, CP 5000 Córdoba, Argentina
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Adil MS, Verma A, Rudraraju M, Narayanan SP, Somanath PR. Akt-independent effects of triciribine on ACE2 expression in human lung epithelial cells: Potential benefits in restricting SARS-CoV2 infection. J Cell Physiol 2021; 236:6597-6606. [PMID: 33624300 PMCID: PMC8014085 DOI: 10.1002/jcp.30343] [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] [Received: 01/06/2021] [Revised: 02/11/2021] [Accepted: 02/12/2021] [Indexed: 02/05/2023]
Abstract
The severe acute respiratory syndrome coronavirus 2 that causes coronavirus disease 2019 (COVID-19) binds to the angiotensin-converting enzyme 2 (ACE2) to gain cellular entry. Akt inhibitor triciribine (TCBN) has demonstrated promising results in promoting recovery from advanced-stage acute lung injury in preclinical studies. In the current study, we tested the direct effect of TCBN on ACE2 expression in human bronchial (H441) and lung alveolar (A549) epithelial cells. Treatment with TCBN resulted in the downregulation of both messenger RNA and protein levels of ACE2 in A549 cells. Since HMGB1 plays a vital role in the inflammatory response in COVID-19, and because hyperglycemia has been linked to increased COVID-19 infections, we determined if HMGB1 and hyperglycemia have any effect on ACE2 expression in lung epithelial cells and whether TCBN has any effect on reversing HMGB1- and hyperglycemia-induced ACE2 expression. We observed increased ACE2 expression with both HMGB1 and hyperglycemia treatment in A549 as well as H441 cells, which were blunted by TCBN treatment. Our findings from this study, combined with our previous reports on the potential benefits of TCBN in the treatment of acute lung injury, generate reasonable optimism on the potential utility of TCBN in the therapeutic management of patients with COVID-19.
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Affiliation(s)
- Mir S. Adil
- Clinical and Experimental Therapeutics, Department of Clinical and Administrative Pharmacy, College of Pharmacy, and Charlie Norwood VA Medical CenterUniversity of GeorgiaAugustaGeorgiaUSA
| | - Arti Verma
- Clinical and Experimental Therapeutics, Department of Clinical and Administrative Pharmacy, College of Pharmacy, and Charlie Norwood VA Medical CenterUniversity of GeorgiaAugustaGeorgiaUSA
| | - Madhuri Rudraraju
- Clinical and Experimental Therapeutics, Department of Clinical and Administrative Pharmacy, College of Pharmacy, and Charlie Norwood VA Medical CenterUniversity of GeorgiaAugustaGeorgiaUSA
| | - S. Priya Narayanan
- Clinical and Experimental Therapeutics, Department of Clinical and Administrative Pharmacy, College of Pharmacy, and Charlie Norwood VA Medical CenterUniversity of GeorgiaAugustaGeorgiaUSA,Vision Discovery Institute, Medical College of GeorgiaAugusta UniversityAugustaGeorgiaUSA
| | - Payaningal R. Somanath
- Clinical and Experimental Therapeutics, Department of Clinical and Administrative Pharmacy, College of Pharmacy, and Charlie Norwood VA Medical CenterUniversity of GeorgiaAugustaGeorgiaUSA,Vascular Biology Center, Medical College of GeorgiaAugusta UniversityAugustaGeorgiaUSA,Department of MedicineAugusta UniversityAugustaGeorgiaUSA
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Sundaresh B, Xu S, Noonan B, Mansour MK, Leong JM, van Opijnen T. Host-informed therapies for the treatment of pneumococcal pneumonia. Trends Mol Med 2021; 27:971-989. [PMID: 34376327 DOI: 10.1016/j.molmed.2021.07.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/06/2021] [Accepted: 07/12/2021] [Indexed: 12/11/2022]
Abstract
Over the past two decades, traditional antimicrobial strategies have lost efficacy due to a rapid rise in antibiotic resistance and limited success in developing new antibiotics. Rather than relying on therapeutics solely targeting the bacterial pathogen, therapies are emerging that simultaneously focus on host responses. Here, we describe the most promising 'host-informed therapies' (HITs) in two categories: those that aid patients with fully functional immune systems, and those that aid patients with perturbed immune processes. Using Streptococcus pneumoniae, the leading cause of bacterial pneumonia, as a case study, we show HITs as an attractive option for supplementing infection management. However, to broaden their applicability and design new strategies, targeted research and clinical trials will be essential.
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Affiliation(s)
| | - Shuying Xu
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA; Graduate Program in Immunology, Tufts Graduate School of Biomedical Sciences, Boston, MA, USA
| | - Brian Noonan
- Stuart B. Levy Center for Integrated Management of Antimicrobial Resistance, Tufts Medical Center, Boston, MA, USA
| | - Michael K Mansour
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA
| | - John M Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, MA, USA; Stuart B. Levy Center for Integrated Management of Antimicrobial Resistance, Tufts Medical Center, Boston, MA, USA.
| | - Tim van Opijnen
- Department of Biology, Boston College, Chestnut Hill, MA, USA; Stuart B. Levy Center for Integrated Management of Antimicrobial Resistance, Tufts Medical Center, Boston, MA, USA.
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12
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A Murine Model for Enhancement of Streptococcus pneumoniae Pathogenicity upon Viral Infection and Advanced Age. Infect Immun 2021; 89:e0047120. [PMID: 34031128 DOI: 10.1128/iai.00471-20] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Streptococcus pneumoniae (pneumococcus) resides asymptomatically in the nasopharynx (NP) but can progress from benign colonizer to lethal pulmonary or systemic pathogen. Both viral infection and aging are risk factors for serious pneumococcal infections. Previous work established a murine model that featured the movement of pneumococcus from the nasopharynx to the lung upon nasopharyngeal inoculation with influenza A virus (IAV) but did not fully recapitulate the severe disease associated with human coinfection. We built upon this model by first establishing pneumococcal nasopharyngeal colonization, then inoculating both the nasopharynx and lungs with IAV. In young (2-month-old) mice, coinfection triggered bacterial dispersal from the nasopharynx into the lungs, pulmonary inflammation, disease, and mortality in a fraction of mice. In aged mice (18 to 24 months), coinfection resulted in earlier and more severe disease. Aging was not associated with greater bacterial burdens but rather with more rapid pulmonary inflammation and damage. Both aging and IAV infection led to inefficient bacterial killing by neutrophils ex vivo. Conversely, aging and pneumococcal colonization also blunted alpha interferon (IFN-α) production and increased pulmonary IAV burden. Thus, in this multistep model, IAV promotes pneumococcal pathogenicity by modifying bacterial behavior in the nasopharynx, diminishing neutrophil function, and enhancing bacterial growth in the lung, while pneumococci increase IAV burden, likely by compromising a key antiviral response. Thus, this model provides a means to elucidate factors, such as age and coinfection, that promote the evolution of S. pneumoniae from asymptomatic colonizer to invasive pathogen, as well as to investigate consequences of this transition on antiviral defense.
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Abstract
Epithelia are structurally integral elements in the fabric of oral mucosa with significant functional roles. Similarly, the gingival epithelium performs uniquely critical tasks in responding to a variety of external stimuli and dangers through the regulation of specific built-in molecular mechanisms in a context-dependent fashion at cellular levels. Gingival epithelial cells form an anatomic architecture that confers defense, robustness, and adaptation toward external aggressions, most critically to colonizing microorganisms, among other functions. Accordingly, recent studies unraveled previously uncharacterized response mechanisms in gingival epithelial cells that are constructed to rapidly exert biocidal effects against invader pathobiotic bacteria, such as Porphyromonas gingivalis, through small danger molecule signaling. The host-adapted bacteria, however, have developed adroit strategies to 1) exploit the epithelia as privileged growth niches and 2) chronically target cellular bactericidal and homeostatic metabolic pathways for successful bacterial persistence. As the overgrowth of colonizing microorganisms in the gingival mucosa can shift from homeostasis to dysbiosis or a diseased state, it is crucial to understand how the innate modulatory molecules are intricately involved in antibacterial pathways and how they shape susceptibility versus resistance in the epithelium toward pathogens. Thus, in this review, we highlight recent discoveries in gingival epithelial cell research in the context of bacterial colonizers. The current knowledge outlined here demonstrates the ability of epithelial cells to possess highly organized defense machineries, which can jointly regulate host-derived danger molecule signaling and integrate specific global responses against opportunistic bacteria to combat microbial incursion and maintain host homeostatic balance. These novel examples collectively suggest that the oral epithelia are equipped with a dynamically robust and interconnected defense system encompassing sensors and various effector molecules that arrange and achieve a fine-tuned and advanced response to diverse bacteria.
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Affiliation(s)
- J.S. Lee
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Ö. Yilmaz
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, SC, USA
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
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14
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Older but Not Wiser: the Age-Driven Changes in Neutrophil Responses during Pulmonary Infections. Infect Immun 2021; 89:IAI.00653-20. [PMID: 33495271 DOI: 10.1128/iai.00653-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Elderly individuals are at increased risk of life-threatening pulmonary infections. Neutrophils are a key determinant of the disease course of pathogen-induced pneumonia. Optimal host defense balances initial robust pulmonary neutrophil responses to control pathogen numbers, ultimately followed by the resolution of inflammation to prevent pulmonary damage. Recent evidence suggests that phenotypic and functional heterogeneity in neutrophils impacts host resistance to pulmonary pathogens. Apart from their apparent role in innate immunity, neutrophils also orchestrate subsequent adaptive immune responses during infection. Thus, the outcome of pulmonary infections can be shaped by neutrophils. This review summarizes the age-driven impairment of neutrophil responses and the contribution of these cells to the susceptibility of the elderly to pneumonia. We describe how aging is accompanied by changes in neutrophil recruitment, resolution, and function. We discuss how systemic and local changes alter the neutrophil phenotype in aged hosts. We highlight the gap in knowledge of whether these changes in neutrophils also contribute to the decline in adaptive immunity seen with age. We further detail the factors that drive dysregulated neutrophil responses in the elderly and the pathways that may be targeted to rebalance neutrophil activity and boost host resistance to pulmonary infections.
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15
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Bhalla M, Nayerhoda R, Tchalla EYI, Abamonte A, Park D, Simmons SR, Pfeifer BA, Bou Ghanem EN. Liposomal Encapsulation of Polysaccharides (LEPS) as an Effective Vaccine Strategy to Protect Aged Hosts Against S. pneumoniae Infection. FRONTIERS IN AGING 2021; 2. [PMID: 35291600 PMCID: PMC8920316 DOI: 10.3389/fragi.2021.798868] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Despite the availability of licensed vaccines, pneumococcal disease caused by the bacteria Streptococcus pneumoniae (pneumococcus), remains a serious infectious disease threat globally. Disease manifestations include pneumonia, bacteremia, and meningitis, resulting in over a million deaths annually. Pneumococcal disease disproportionally impacts older adults aged ≥65 years. Interventions are complicated through a combination of complex disease progression and 100 different bacterial capsular polysaccharide serotypes. This has made it challenging to develop a broad vaccine against S. pneumoniae, with current options utilizing capsular polysaccharides as the primary antigenic content. However, current vaccines are substantially less effective in protecting the elderly. We previously developed a Liposomal Encapsulation of Polysaccharides (LEPS) vaccine platform, designed around limitations of current pneumococcal vaccines, that allowed the noncovalent coupling of polysaccharide and protein antigen content and protected young hosts against pneumococcal infection in murine models. In this study, we modified the formulation to make it more economical and tested the novel LEPS vaccine in aged hosts. We found that in young mice (2-3 months), LEPS elicited comparable responses to the pneumococcal conjugate vaccine Prevnar-13. Further, LEPS immunization of old mice (18-22 months) induced comparable antibody levels and improved antibody function compared to Prevnar-13. Importantly, LEPS protected old mice against both invasive and lung localized pneumococcal infections. In summary, LEPS is an alternative and effective vaccine strategy that protects aged hosts against different manifestations of pneumococcal disease.
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Affiliation(s)
- Manmeet Bhalla
- Department of Microbiology and Immunology, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Roozbeh Nayerhoda
- Department of Biomedical Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Essi Y I Tchalla
- Department of Microbiology and Immunology, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Alexsandra Abamonte
- Department of Microbiology and Immunology, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Dongwon Park
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Shaunna R Simmons
- Department of Microbiology and Immunology, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Blaine A Pfeifer
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, NY, United States.,Gene and Tissue Engineering Center, University at Buffalo, The State University of New York, Buffalo, NY, United States
| | - Elsa N Bou Ghanem
- Department of Microbiology and Immunology, University at Buffalo, The State University of New York, Buffalo, NY, United States
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16
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Higher pharyngeal epithelial gene expression of angiotensin-converting Enzyme-2 in patients with upper respiratory infection. Int J Infect Dis 2020; 103:378-380. [PMID: 33278618 PMCID: PMC7708802 DOI: 10.1016/j.ijid.2020.11.197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 11/20/2020] [Accepted: 11/26/2020] [Indexed: 11/23/2022] Open
Abstract
We analyzed the expression of ACE2 in the pharyngeal epithelium and examined its relationship with clinical features and serological parameters in patients with upper respiratory infection (URI). The expression level of the ACE2 gene was significantly higher in patients with URI (n = 125) than in healthy control (HC) individuals (n = 52) (p < 0.0001). The ACE2 gene expression level was significantly and positively correlated with age (r=0.1799, p = 0.0447) and body temperature (r=0.1927, p = 0.0427), which may help explain increasing coinfections with SARS-CoV-2 and other respiratory pathogens.
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17
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Bhalla M, Simmons SR, Abamonte A, Herring SE, Roggensack SE, Bou Ghanem EN. Extracellular adenosine signaling reverses the age-driven decline in the ability of neutrophils to kill Streptococcus pneumoniae. Aging Cell 2020; 19:e13218. [PMID: 32790148 PMCID: PMC7576260 DOI: 10.1111/acel.13218] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/23/2020] [Accepted: 07/19/2020] [Indexed: 12/23/2022] Open
Abstract
The elderly are susceptible to serious infections by Streptococcus pneumoniae (pneumococcus), which calls for a better understanding of the pathways driving the decline in host defense in aging. We previously found that extracellular adenosine (EAD) shaped polymorphonuclear cell (PMN) responses, which are crucial for controlling infection. EAD is produced by CD39 and CD73, and signals via A1, A2A, A2B, and A3 receptors. The objective of this study was to explore the age‐driven changes in the EAD pathway and its impact on PMN function. We found in comparison to young mice, PMNs from old mice expressed significantly less CD73, but similar levels of CD39 and adenosine receptors. PMNs from old mice failed to efficiently kill pneumococci ex vivo; however, supplementation with adenosine rescued this defect. Importantly, transfer of PMNs expressing CD73 from young mice reversed the susceptibility of old mice to pneumococcal infection. To identify which adenosine receptor(s) is involved, we used specific agonists and inhibitors. We found that A1 receptor signaling was crucial for PMN function as inhibition or genetic ablation of A1 impaired the ability of PMNs from young mice to kill pneumococci. Importantly, activation of A1 receptors rescued the age‐associated defect in PMN function. In exploring mechanisms, we found that PMNs from old mice failed to efficiently kill engulfed pneumococci and that A1 receptor controlled intracellular killing. In summary, targeting the EAD pathway reverses the age‐driven decline in PMN antimicrobial function, which has serious implications in combating infections.
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Affiliation(s)
- Manmeet Bhalla
- Department of Microbiology and Immunology University at Buffalo School of Medicine Buffalo NY USA
| | - Shaunna R. Simmons
- Department of Microbiology and Immunology University at Buffalo School of Medicine Buffalo NY USA
| | - Alexsandra Abamonte
- Department of Microbiology and Immunology University at Buffalo School of Medicine Buffalo NY USA
| | - Sydney E. Herring
- Department of Microbiology and Immunology University at Buffalo School of Medicine Buffalo NY USA
| | - Sara E. Roggensack
- Department of Molecular Biology and Microbiology Tufts University School of Medicine Boston MA USA
| | - Elsa N. Bou Ghanem
- Department of Microbiology and Immunology University at Buffalo School of Medicine Buffalo NY USA
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18
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Siwapornchai N, Lee JN, Tchalla EYI, Bhalla M, Yeoh JH, Roggensack SE, Leong JM, Bou Ghanem EN. Extracellular adenosine enhances the ability of PMNs to kill Streptococcus pneumoniae by inhibiting IL-10 production. J Leukoc Biol 2020; 108:867-882. [PMID: 32017200 DOI: 10.1002/jlb.4ma0120-115rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 01/14/2020] [Accepted: 01/17/2020] [Indexed: 12/18/2022] Open
Abstract
Polymorphonuclear leukocytes (PMNs) are crucial for initial control of Streptococcus pneumoniae (pneumococcus) lung infection; however, as the infection progresses their persistence in the lungs becomes detrimental. Here we explored why the antimicrobial efficacy of PMNs declines over the course of infection. We found that the progressive inability of PMNs to control infection correlated with phenotypic differences characterized by a decrease in CD73 expression, an enzyme required for production of extracellular adenosine (EAD). EAD production by CD73 was crucial for the ability of both murine and human PMNs to kill S. pneumoniae. In exploring the mechanisms by which CD73 controlled PMN function, we found that CD73 mediated its antimicrobial activity by inhibiting IL-10 production. PMNs from wild-type mice did not increase IL-10 production in response to S. pneumoniae; however, CD73-/- PMNs up-regulated IL-10 production upon pneumococcal infection in vitro and during lung challenge. IL-10 inhibited the ability of WT PMNs to kill pneumococci. Conversely, blocking IL-10 boosted the bactericidal activity of CD73-/- PMNs as well as host resistance of CD73-/- mice to pneumococcal pneumonia. CD73/IL-10 did not affect apoptosis, bacterial uptake, and intracellular killing or production of antimicrobial neutrophil elastase and myeloperoxidase. Rather, inhibition of IL-10 production by CD73 was important for optimal reactive oxygen species (ROS) production by PMNs. ROS contributed to PMN antimicrobial function as their removal or detoxification impaired the ability of PMNs to efficiently kill S. pneumoniae. This study demonstrates that CD73 controls PMN antimicrobial phenotype during S. pneumoniae infection.
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Affiliation(s)
- Nalat Siwapornchai
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - James N Lee
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Essi Y I Tchalla
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Manmeet Bhalla
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Jun Hui Yeoh
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
| | - Sara E Roggensack
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - John M Leong
- Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Elsa N Bou Ghanem
- Department of Microbiology and Immunology, University at Buffalo School of Medicine, Buffalo, New York, USA
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19
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LeMessurier KS, Tiwary M, Morin NP, Samarasinghe AE. Respiratory Barrier as a Safeguard and Regulator of Defense Against Influenza A Virus and Streptococcus pneumoniae. Front Immunol 2020; 11:3. [PMID: 32117216 PMCID: PMC7011736 DOI: 10.3389/fimmu.2020.00003] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/03/2020] [Indexed: 12/27/2022] Open
Abstract
The primary function of the respiratory system of gas exchange renders it vulnerable to environmental pathogens that circulate in the air. Physical and cellular barriers of the respiratory tract mucosal surface utilize a variety of strategies to obstruct microbe entry. Physical barrier defenses including the surface fluid replete with antimicrobials, neutralizing immunoglobulins, mucus, and the epithelial cell layer with rapidly beating cilia form a near impenetrable wall that separates the external environment from the internal soft tissue of the host. Resident leukocytes, primarily of the innate immune branch, also maintain airway integrity by constant surveillance and the maintenance of homeostasis through the release of cytokines and growth factors. Unfortunately, pathogens such as influenza virus and Streptococcus pneumoniae require hosts for their replication and dissemination, and prey on the respiratory tract as an ideal environment causing severe damage to the host during their invasion. In this review, we outline the host-pathogen interactions during influenza and post-influenza bacterial pneumonia with a focus on inter- and intra-cellular crosstalk important in pulmonary immune responses.
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Affiliation(s)
- Kim S LeMessurier
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Division of Pulmonology, Allergy-Immunology, and Sleep, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Le Bonheur Children's Hospital, Children's Foundation Research Institute, Memphis, TN, United States
| | - Meenakshi Tiwary
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Division of Pulmonology, Allergy-Immunology, and Sleep, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Le Bonheur Children's Hospital, Children's Foundation Research Institute, Memphis, TN, United States
| | - Nicholas P Morin
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Division of Critical Care Medicine, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Amali E Samarasinghe
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Division of Pulmonology, Allergy-Immunology, and Sleep, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States.,Le Bonheur Children's Hospital, Children's Foundation Research Institute, Memphis, TN, United States
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