1
|
Guo Y, Zheng B, Tian P, Zheng J, Li Y, Ding X, Xue W, Ding C. HLA class II antibody activation of endothelial cells induces M2 macrophage differentiation in peripheral blood. Clin Exp Nephrol 2023; 27:309-320. [PMID: 36611129 DOI: 10.1007/s10157-022-02307-9] [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: 04/01/2022] [Accepted: 11/30/2022] [Indexed: 01/09/2023]
Abstract
BACKGROUND Donor-specific human leukocyte antigen (HLA) class II antibodies (HLA-II Abs) combined with allogeneic endothelial cells (ECs) mediate high-risk rejection in kidney transplant patients. Macrophage accumulation is a significant histological feature of antibody-mediated rejection (AMR) in kidney transplant patients. Here, we further investigated the effect of HLA-II Abs on macrophage phenotypes to provide theoretical basis for clinical treatment of AMR. METHODS We prepared an experimental model containing HLA-II Ab-stimulated microvascular ECs and peripheral blood mononuclear cells (PBMCs) co-culture and explored the potential relationship of HLA-II Ab, ECs activation, and macrophage differentiation. Immune phenotype of macrophage subsets was analyzed and quantified by flow cytometry. HLA-II Ab activation of ECs induces M2 macrophage differentiation signal pathways which were investigated by qPCR and western blotting. RESULTS The stimulation of ECs by F(ab')2 fragment of HLA-II Abs led to phosphorylation of PI3K, Akt, and mTOR, which mediated IL-10, ICAM-1, VCAM-1 secretion. The enhanced ICAM-1 and IL-10 promoted the migration of PBMCs and their differentiation into CD68+ and CD163+ (M2-type) macrophages, respectively, but not CD86+ macrophages. CONCLUSION These findings revealed the PI3K/Akt/mTOR signal pathways activated by HLA-II Abs in ECs and the immune regulation ability of HLA-II Abs to induce PBMC differentiation.
Collapse
Affiliation(s)
- Yingcong Guo
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
| | - Bingxuan Zheng
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
| | - Puxun Tian
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Jin Zheng
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Yang Li
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Xiaoming Ding
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Wujun Xue
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Chenguang Ding
- Department of Kidney Transplantation, Nephropathy Hospital, The First Affiliated Hospital of Xi'an Jiaotong University, No. 277 West Yanta Road, Xi'an, 710061, China.
- Institute of Organ Transplantation, Xi'an Jiaotong University, Xi'an, 710061, China.
| |
Collapse
|
2
|
NOD2 Agonism Counter-Regulates Human Type 2 T Cell Functions in Peripheral Blood Mononuclear Cell Cultures: Implications for Atopic Dermatitis. Biomolecules 2023; 13:biom13020369. [PMID: 36830738 PMCID: PMC9953199 DOI: 10.3390/biom13020369] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 01/31/2023] [Accepted: 02/03/2023] [Indexed: 02/18/2023] Open
Abstract
Atopic dermatitis (AD) is known as a skin disease; however, T cell immunopathology found in blood is associated with its severity. Skin Staphylococcus aureus (S. aureus) and associated host-pathogen dynamics are important to chronic T helper 2 (Th2)-dominated inflammation in AD, yet they remain poorly understood. This study sought to investigate the effects of S. aureus-derived molecules and skin alarmins on human peripheral blood mononuclear cells, specifically testing Th2-type cells, cytokines, and chemokines known to be associated with AD. We first show that six significantly elevated Th2-related chemokine biomarkers distinguish blood from adult AD patients compared to healthy controls ex vivo; in addition, TARC/CCL17, LDH, and PDGF-AA/AB correlated significantly with disease severity. We then demonstrate that these robust AD-associated biomarkers, as well as associated type 2 T cell functions, are readily reproduced from healthy blood mononuclear cells exposed to the alarmin TSLP and the S. aureus superantigen SEB in a human in vitro model, including IL-13, IL-5, and TARC secretion as well as OX-40-expressing activated memory T cells. We further show that the agonism of nucleotide-binding oligomerization domain-containing protein (NOD)2 inhibits this IL-13 secretion and memory Th2 and Tc2 cell functional activation while inducing significantly increased pSTAT3 and IL-6, both critical for Th17 cell responses. These findings identify NOD2 as a potential regulator of type 2 immune responses in humans and highlight its role as an endogenous inhibitor of pathogenic IL-13 that may open avenues for its therapeutic targeting in AD.
Collapse
|
3
|
Afshar M, Møllebjerg A, Minero GA, Hollensteiner J, Poehlein A, Himmelbach A, Lange J, Meyer RL, Brüggemann H. Biofilm formation and inflammatory potential of Staphylococcus saccharolyticus: A possible cause of orthopedic implant-associated infections. Front Microbiol 2022; 13:1070201. [DOI: 10.3389/fmicb.2022.1070201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Accepted: 11/09/2022] [Indexed: 11/29/2022] Open
Abstract
Staphylococcus saccharolyticus, a coagulase-negative staphylococcal species, has some unusual characteristics for human-associated staphylococci, such as slow growth and its preference for anoxic culture conditions. This species is a relatively abundant member of the human skin microbiota, but its microbiological properties, as well as the pathogenic potential, have scarcely been investigated so far, despite being occasionally isolated from different types of infections including orthopedic implant-associated infections. Here, we investigated the growth and biofilm properties of clinical isolates of S. saccharolyticus and determined host cell responses. Growth assessments in anoxic and oxic conditions revealed strain-dependent outcomes, as some strains can also grow aerobically. All tested strains of S. saccharolyticus were able to form biofilm in a microtiter plate assay. Strain-dependent differences were determined by optical coherence tomography, revealing that medium supplementation with glucose and sodium chloride enhanced biofilm formation. Visualization of the biofilm by confocal laser scanning microscopy revealed the role of extracellular DNA in the biofilm structure. In addition to attached biofilms, S. saccharolyticus also formed bacterial aggregates at an early stage of growth. Transcriptome analysis of biofilm-grown versus planktonic cells revealed a set of upregulated genes in biofilm-embedded cells, including factors involved in adhesion, colonization, and competition such as epidermin, type I toxin-antitoxin system, and phenol-soluble modulins (beta and epsilon). To investigate consequences for the host after encountering S. saccharolyticus, cytokine profiling and host cell viability were assessed by infection experiments with differentiated THP-1 cells. The microorganism strongly triggered the secretion of the tested pro-inflammatory cyto- and chemokines IL-6, IL-8, and TNF-alpha, determined at 24 h post-infection. S. saccharolyticus was less cytotoxic than Staphylococcus aureus. Taken together, the results indicate that S. saccharolyticus has substantial pathogenic potential. Thus, it can be a potential cause of orthopedic implant-associated infections and other types of deep-seated infections.
Collapse
|
4
|
Staphylococcus aureus-induced immunosuppression mediated by IL-10 and IL-27 facilitates nasal colonisation. PLoS Pathog 2022; 18:e1010647. [PMID: 35776778 PMCID: PMC9282462 DOI: 10.1371/journal.ppat.1010647] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 07/14/2022] [Accepted: 06/06/2022] [Indexed: 11/19/2022] Open
Abstract
Staphylococcus aureus persistently colonises the anterior nares of a significant proportion of the healthy population, however the local immune response elicited during S. aureus nasal colonisation remains ill-defined. Local activation of IL-17/IL-22 producing T cells are critical for controlling bacterial clearance from the nasal cavity. However, recurrent and long-term colonisation is commonplace indicating efficient clearance does not invariably occur. Here we identify a central role for the regulatory cytokine IL-10 in facilitating bacterial persistence during S. aureus nasal colonisation in a murine model. IL-10 is produced rapidly within the nasal cavity following S. aureus colonisation, primarily by myeloid cells. Colonised IL-10-/- mice demonstrate enhanced IL-17+ and IL-22+ T cell responses and more rapidly clear bacteria from the nasal tissues as compared with wild-type mice. S. aureus also induces the regulatory cytokine IL-27 within the nasal tissue, which acts upstream of IL-10 promoting its production. IL-27 blockade reduces IL-10 production within the nasal cavity and improves bacterial clearance. TLR2 signalling was confirmed to be central to controlling the IL-10 response. Our findings conclude that during nasal colonisation S. aureus creates an immunosuppressive microenvironment through the local induction of IL-27 and IL-10, to dampen protective T cell responses and facilitate its persistence. Nasal colonisation by the bacterium Staphylococcus aureus is a very common occurrence in the human population. However there is a lack of knowledge on the immune response that controls nasal colonisation. It is known that a local pro-inflammatory immune response is important for bacterial clearance, however sustained colonisation is commonplace suggesting efficient clearance may not be occurring. Here we demonstrate for the first time that S. aureus is manipulating the host immune response by promoting immunosuppression in the nasal cavity which enables bacterial survival. We found that the regulatory proteins IL-10 and IL-27 are central to this suppressive response and result in reduced protective T cell responses. We also demonstrate that S. aureus is inducing IL-27 production to enhance IL-10 production in order to prolong bacterial colonisation. Our findings show that the host-pathogen interaction during nasal colonisation is more complex than previously described and that S. aureus is capable of manipulating the regulatory immune response of the host for its’ own benefit.
Collapse
|
5
|
Chen SJ, Zhang CY, Yu D, Lin CJ, Xu HJ, Hu CM. Selenium Alleviates Inflammation in Staphylococcus aureus-Induced Mastitis via MerTK-Dependent Activation of the PI3K/Akt/mTOR Pathway in Mice. Biol Trace Elem Res 2022; 200:1750-1762. [PMID: 34185276 DOI: 10.1007/s12011-021-02794-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Accepted: 06/11/2021] [Indexed: 11/29/2022]
Abstract
Mastitis caused by Staphylococcus aureus infection not only causes serious economic losses, but also affects human health. Se plays an important role in body immunity. However, the mechanisms by which Se regulates mastitis induced by S. aureus are still principally unknown. The purpose of this study is to investigate whether Se can inhibit mastitis induced by S. aureus through regulation of MerTK. Sixty BALB/c female mice were fed low, normal, or high Se concentrations for 7 weeks and then randomly divided into six groups (Se-Low Control group (LSN), Se-Normal Control group (NSN), Se-High Control group (HSN), Se-Low S. aureus group (LSS), Se-Normal S. aureus group (NSS), Se-High S. aureus group (HSS)). The regulation of Se on MerTK was detected via histopathological staining, western blot analysis, enzyme-linked immunosorbent assay, and qRT-PCR. With increased selenium concentrations, the levels of IL-1β, IL-6, and TNF-α decreased, while the phosphorylation levels of MerTK, PI3K, AKT, and mTOR increased. Therefore, this study showed that Se could alleviate S. aureus mastitis by activating MerTK and PI3K/AKT/mTOR pathway.
Collapse
Affiliation(s)
- Si-Jie Chen
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Chen-Yuan Zhang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Di Yu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Chang-Jie Lin
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Hao-Jun Xu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Chang-Min Hu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| |
Collapse
|
6
|
Cordero M, García-Fernández J, Acosta IC, Yepes A, Avendano-Ortiz J, Lisowski C, Oesterreicht B, Ohlsen K, Lopez-Collazo E, Förstner KU, Eulalio A, Lopez D. The induction of natural competence adapts staphylococcal metabolism to infection. Nat Commun 2022; 13:1525. [PMID: 35314690 PMCID: PMC8938553 DOI: 10.1038/s41467-022-29206-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 03/03/2022] [Indexed: 11/26/2022] Open
Abstract
A central question concerning natural competence is why orthologs of competence genes are conserved in non-competent bacterial species, suggesting they have a role other than in transformation. Here we show that competence induction in the human pathogen Staphylococcus aureus occurs in response to ROS and host defenses that compromise bacterial respiration during infection. Bacteria cope with reduced respiration by obtaining energy through fermentation instead. Since fermentation is energetically less efficient than respiration, the energy supply must be assured by increasing the glycolytic flux. The induction of natural competence increases the rate of glycolysis in bacteria that are unable to respire via upregulation of DNA- and glucose-uptake systems. A competent-defective mutant showed no such increase in glycolysis, which negatively affects its survival in both mouse and Galleria infection models. Natural competence foster genetic variability and provides S. aureus with additional nutritional and metabolic possibilities, allowing it to proliferate during infection. Orthologs of natural competence genes are conserved in non-competent bacterial species, suggesting they have a role other than in transformation. Here, the authors show that competence induction in Staphylococcus aureus occurs in response to reactive oxygen species and host defenses that compromise bacterial respiration during infection, leading to increased DNA and glucose uptake and glycolytic flux.
Collapse
|
7
|
Peruń A, Gębicka M, Biedroń R, Skalska P, Józefowski S. The CD36 and SR-A/CD204 scavenger receptors fine-tune Staphylococcus aureus-stimulated cytokine production in mouse macrophages. Cell Immunol 2022; 372:104483. [DOI: 10.1016/j.cellimm.2022.104483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 12/20/2021] [Accepted: 01/11/2022] [Indexed: 11/03/2022]
|
8
|
Herold R, Scholtysik R, Moroniak S, Weiss C, Ishikawa H, Schroten H, Schwerk C. Capsule-dependent impact of MAPK signalling on host cell invasion and immune response during infection of the choroid plexus epithelium by Neisseria meningitidis. Fluids Barriers CNS 2021; 18:53. [PMID: 34863201 PMCID: PMC8643193 DOI: 10.1186/s12987-021-00288-7] [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: 08/24/2021] [Accepted: 11/16/2021] [Indexed: 01/15/2023] Open
Abstract
Background The Gram-negative bacterium Neisseria meningitidis (Nm) can cause meningitis in humans, but the host signalling pathways manipulated by Nm during central nervous system (CNS) entry are not completely understood. Methods We investigate the role of the mitogen-activated protein kinases (MAPK) Erk1/2 and p38 in an in vitro model of the blood-cerebrospinal fluid barrier (BCSFB) based on human epithelial choroid plexus (CP) papilloma (HIBCPP) cells during infection with Nm serogroup B (NmB) and serogroup C (NmC) strains. A transcriptome analysis of HIBCPP cells following infection with Nm by massive analysis of cDNA ends (MACE) was done to further characterize the cellular response to infection of the barrier. Results Interestingly, whereas NmB and NmC wild type strains required active Erk1/2 and p38 pathways for infection, invasion by capsule-deficient mutants was independent of Erk1/2 and, in case of the NmB strain, of p38 activity. The transcriptome analysis of HIBCPP cells following infection with Nm demonstrated specific regulation of genes involved in the immune response dependent on Erk1/2 signalling. Gene ontology (GO) analysis confirmed loss of MAPK signalling after Erk1/2 inhibition and revealed an additional reduction of cellular responses including NFκB and JAK-STAT signalling. Interestingly, GO terms related to TNF signalling and production of IL6 were lost specifically following Erk1/2 inhibition during infection with wild type Nm, which correlated with the reduced infection rates by the wild type in absence of Erk1/2 signalling. Conclusion Our data point towards a role of MAPK signalling during infection of the CP epithelium by Nm, which is strongly influenced by capsule expression, and affects infection rates as well as the host cell response. Supplementary Information The online version contains supplementary material available at 10.1186/s12987-021-00288-7.
Collapse
Affiliation(s)
- Rosanna Herold
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - René Scholtysik
- Genomics & Transcriptomics Facility, Institute of Cell Biology, University Hospital Essen, Virchowstraße 173, 45122, Essen, Germany
| | - Selina Moroniak
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Christel Weiss
- Department of Medical Statistics and Biomathematics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Hiroshi Ishikawa
- Laboratory of Clinical Regenerative Medicine, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, 1-1-1Tennodai, Tsukuba, Ibaraki, 305-8575, Japan
| | - Horst Schroten
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Christian Schwerk
- Pediatric Infectious Diseases, Department of Pediatrics, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| |
Collapse
|
9
|
Udayan S, Buttó LF, Rossini V, Velmurugan J, Martinez-Lopez M, Sancho D, Melgar S, O'Toole PW, Nally K. Macrophage cytokine responses to commensal Gram-positive Lactobacillus salivarius strains are TLR2-independent and Myd88-dependent. Sci Rep 2021; 11:5896. [PMID: 33723368 PMCID: PMC7961041 DOI: 10.1038/s41598-021-85347-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 02/26/2021] [Indexed: 01/31/2023] Open
Abstract
The mechanisms through which cells of the host innate immune system distinguish commensal bacteria from pathogens are currently unclear. Toll-like receptors (TLRs) are a class of pattern recognition receptors (PRRs) expressed by host cells which recognize microbe-associated molecular patterns (MAMPs) common to both commensal and pathogenic bacteria. Of the different TLRs, TLR2/6 recognize bacterial lipopeptides and trigger cytokines responses, especially to Gram-positive and Gram-negative pathogens. We report here that TLR2 is dispensable for triggering macrophage cytokine responses to different strains of the Gram-positive commensal bacterial species Lactobacillus salivarius. The L. salivarius UCC118 strain strongly upregulated expression of the PRRs, Mincle (Clec4e), TLR1 and TLR2 in macrophages while downregulating other TLR pathways. Cytokine responses triggered by L. salivarius UCC118 were predominantly TLR2-independent but MyD88-dependent. However, macrophage cytokine responses triggered by another Gram-positive commensal bacteria, Bifidobacterium breve UCC2003 were predominantly TLR2-dependent. Thus, we report a differential requirement for TLR2-dependency in triggering macrophage cytokine responses to different commensal Gram-positive bacteria. Furthermore, TNF-α responses to the TLR2 ligand FSL-1 and L. salivarius UCC118 were partially Mincle-dependent suggesting that PRR pathways such as Mincle contribute to the recognition of MAMPs on distinct Gram-positive commensal bacteria. Ultimately, integration of signals from these different PRR pathways and other MyD88-dependent pathways may determine immune responses to commensal bacteria at the host-microbe interface.
Collapse
Affiliation(s)
- Sreeram Udayan
- APC Microbiome Ireland, University College Cork, Cork, Ireland
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | | | - Valerio Rossini
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | | | - Maria Martinez-Lopez
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - David Sancho
- Immunobiology Laboratory, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Silvia Melgar
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | - Paul W O'Toole
- APC Microbiome Ireland, University College Cork, Cork, Ireland
- School of Microbiology, University College Cork, Cork, Ireland
| | - Ken Nally
- APC Microbiome Ireland, University College Cork, Cork, Ireland.
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland.
| |
Collapse
|
10
|
de Morais SD, Kak G, Menousek JP, Kielian T. Immunopathogenesis of Craniotomy Infection and Niche-Specific Immune Responses to Biofilm. Front Immunol 2021; 12:625467. [PMID: 33708216 PMCID: PMC7940520 DOI: 10.3389/fimmu.2021.625467] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/05/2021] [Indexed: 02/06/2023] Open
Abstract
Bacterial infections in the central nervous system (CNS) can be life threatening and often impair neurological function. Biofilm infection is a complication following craniotomy, a neurosurgical procedure that involves the removal and replacement of a skull fragment (bone flap) to access the brain for surgical intervention. The incidence of infection following craniotomy ranges from 1% to 3% with approximately half caused by Staphylococcus aureus (S. aureus). These infections present a significant therapeutic challenge due to the antibiotic tolerance of biofilm and unique immune properties of the CNS. Previous studies have revealed a critical role for innate immune responses during S. aureus craniotomy infection. Experiments using knockout mouse models have highlighted the importance of the pattern recognition receptor Toll-like receptor 2 (TLR2) and its adaptor protein MyD88 for preventing S. aureus outgrowth during craniotomy biofilm infection. However, neither molecule affected bacterial burden in a mouse model of S. aureus brain abscess highlighting the distinctions between immune regulation of biofilm vs. planktonic infection in the CNS. Furthermore, the immune responses elicited during S. aureus craniotomy infection are distinct from biofilm infection in the periphery, emphasizing the critical role for niche-specific factors in dictating S. aureus biofilm-leukocyte crosstalk. In this review, we discuss the current knowledge concerning innate immunity to S. aureus craniotomy biofilm infection, compare this to S. aureus biofilm infection in the periphery, and discuss the importance of anatomical location in dictating how biofilm influences inflammatory responses and its impact on bacterial clearance.
Collapse
Affiliation(s)
- Sharon Db de Morais
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Gunjan Kak
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Joseph P Menousek
- Department of Neurosurgery, University of Nebraska Medical Center, Omaha, NE, United States
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| |
Collapse
|
11
|
Abstract
The mechanistic (or mammalian) target of rapamycin (mTOR) is considered as a critical regulatory enzyme involved in essential signaling pathways affecting cell growth, cell proliferation, protein translation, regulation of cellular metabolism, and cytoskeletal structure. Also, mTOR signaling has crucial roles in cell homeostasis via processes such as autophagy. Autophagy prevents many pathogen infections and is involved on immunosurveillance and pathogenesis. Immune responses and autophagy are therefore key host responses and both are linked by complex mTOR regulatory mechanisms. In recent years, the mTOR pathway has been highlighted in different diseases such as diabetes, cancer, and infectious and parasitic diseases including leishmaniasis, toxoplasmosis, and malaria. The current review underlines the implications of mTOR signals and intricate networks on pathogen infections and the modulation of this master regulator by parasites. Parasitic infections are able to induce dynamic metabolic reprogramming leading to mTOR alterations in spite of many other ways impacting this regulatory network. Accordingly, the identification of parasite effects and interactions over such a complex modulation might reveal novel information regarding the biology of the abovementioned parasites and might allow the development of therapeutic strategies against parasitic diseases. In this sense, the effects of inhibiting the mTOR pathways are also considered in this context in the light of their potential for the prevention and treatment of parasitic diseases.
Collapse
|
12
|
Zahoor A, Yang C, Yang Y, Akhtar M, Umar T, Khan MA, Ahmad S, Deng G, Guo MY. MerTK negatively regulates Staphylococcus aureus induced inflammatory response via SOCS1/SOCS3 and Mal. Immunobiology 2020; 225:151960. [PMID: 32747017 DOI: 10.1016/j.imbio.2020.151960] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 04/01/2020] [Accepted: 05/13/2020] [Indexed: 12/22/2022]
Abstract
OBJECTIVE Staphylococcus aureus (S. aureus), one of Gram-positive pathogen, is frequently associated with acute lung inflammation. The central feature of S. aureus acute lung inflammation are pulmonary dysfunctioning and impeded host defence response, which cause failure in inflammatory cytokines homeostasis and leads to serious tissue damage. However, the role of the Mer receptor tyrosine kinase (MerTK) in the lung following S. aureus infection remains elusive. Here, we investigate whether MerTK alleviates S. aureus induced uncontrolled inflammation through negatively regulating toll-like receptor 2 and 6 (TLR2/ TLR6) via suppressor of cytokine signalling 1, 3 (SOCS1/SOCS3). METHODS AND RESULTS We found in mice lung tissues and RAW 264.7 macrophages upon S. aureus infection activates TLR2 and TLR6 driven mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signalling pathways, resulting in production of inflammatory cytokines including tumour necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin 6 (IL-6). Furthermore, S. aureus-infection groups showed a significant up-regulation of MerTK which serves as mediator of SOCS1 and SOCS3. Subsequently, through feedback mechanism SOCS1/3 degrade Mal, resulting in inhibition of downstream TLR mediated inflammatory pathways. Moreover, MerTK-/- mice lung tissues and silencing MerTK in RAW 264.7 inhibited the S. aureus-induced activation of MerTK, which significantly upregulated the phosphorylation of crucial protein in MAPKs (ERK, JNK, p38) and NF-κB (IĸBα, p65) signalling pathways, as well as the production of pro-inflammatory cytokines. CONCLUSION Collectively, these findings indicate the important role of MerTK in self-regulatory resolution of S. aureus-induced inflammatory pathways and cytokines through intrinsic SOCS1 and SOCS3 repressed feedback on TLR2, TLR6 both in vivo and in vitro.
Collapse
Affiliation(s)
- Arshad Zahoor
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China; College of Veterinary Sciences, The University of Agriculture Peshawar, Pakistan
| | - Chao Yang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Yaping Yang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Muhammad Akhtar
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Talha Umar
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Murad Ali Khan
- College of Veterinary Sciences, The University of Agriculture Peshawar, Pakistan
| | - Shakoor Ahmad
- College of Veterinary Sciences, The University of Agriculture Peshawar, Pakistan
| | - Ganzhen Deng
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| | - Meng-Yao Guo
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
| |
Collapse
|
13
|
Kelly AM, McLoughlin RM. Target the Host, Kill the Bug; Targeting Host Respiratory Immunosuppressive Responses as a Novel Strategy to Improve Bacterial Clearance During Lung Infection. Front Immunol 2020; 11:767. [PMID: 32425944 PMCID: PMC7203494 DOI: 10.3389/fimmu.2020.00767] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/06/2020] [Indexed: 12/14/2022] Open
Abstract
The lung is under constant pressure to protect the body from invading bacteria. An effective inflammatory immune response must be tightly orchestrated to ensure complete clearance of any invading bacteria, while simultaneously ensuring that inflammation is kept under strict control to preserve lung viability. Chronic bacterial lung infections are seen as a major threat to human life with the treatment of these infections becoming more arduous as the prevalence of antibiotic resistance becomes increasingly commonplace. In order to survive within the lung bacteria target the host immune system to prevent eradication. Many bacteria directly target inflammatory cells and cytokines to impair inflammatory responses. However, bacteria also have the capacity to take advantage of and strongly promote anti-inflammatory immune responses in the host lung to inhibit local pro-inflammatory responses that are critical to bacterial elimination. Host cells such as T regulatory cells and myeloid-derived suppressor cells are often enhanced in number and activity during chronic pulmonary infection. By increasing suppressive cell populations and cytokines, bacteria promote a permissive environment suitable for their prolonged survival. This review will explore the anti-inflammatory aspects of the lung immune system that are targeted by bacteria and how bacterial-induced immunosuppression could be inhibited through the use of host-directed therapies to improve treatment options for chronic lung infections.
Collapse
Affiliation(s)
- Alanna M Kelly
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Rachel M McLoughlin
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| |
Collapse
|
14
|
Nouwen LV, Everts B. Pathogens MenTORing Macrophages and Dendritic Cells: Manipulation of mTOR and Cellular Metabolism to Promote Immune Escape. Cells 2020; 9:cells9010161. [PMID: 31936570 PMCID: PMC7017145 DOI: 10.3390/cells9010161] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/01/2020] [Accepted: 01/07/2020] [Indexed: 02/06/2023] Open
Abstract
Myeloid cells, including macrophages and dendritic cells, represent an important first line of defense against infections. Upon recognition of pathogens, these cells undergo a metabolic reprogramming that supports their activation and ability to respond to the invading pathogens. An important metabolic regulator of these cells is mammalian target of rapamycin (mTOR). During infection, pathogens use host metabolic pathways to scavenge host nutrients, as well as target metabolic pathways for subversion of the host immune response that together facilitate pathogen survival. Given the pivotal role of mTOR in controlling metabolism and DC and macrophage function, pathogens have evolved strategies to target this pathway to manipulate these cells. This review seeks to discuss the most recent insights into how pathogens target DC and macrophage metabolism to subvert potential deleterious immune responses against them, by focusing on the metabolic pathways that are known to regulate and to be regulated by mTOR signaling including amino acid, lipid and carbohydrate metabolism, and autophagy.
Collapse
|
15
|
Ji Y, Bolhuis A, Watson ML. Staphylococcus aureus products subvert the Burkholderia cenocepacia-induced inflammatory response in airway epithelial cells. J Med Microbiol 2019; 68:1813-1822. [PMID: 31674896 DOI: 10.1099/jmm.0.001100] [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: 12/17/2022] Open
Abstract
Introduction. Chronic pulmonary infection is associated with colonization with multiple micro-organisms but host-microbe and microbe-microbe interactions are poorly understood.Aim. This study aims to investigate the differences in host responses to mono- and co-infection with S. aureus and B. cenocepacia in human airway epithelial cells.Methodology. We assessed the effect of co-infection with B. cenocepacia and S. aureus on host signalling and inflammatory responses in the human airway epithelial cell line 16HBE, using ELISA and western blot analysis.Results. The results show that B. cenocepacia activates MAPK and NF-κB signalling pathways, subsequently eliciting robust interleukin (IL)-8 production. However, when airway epithelial cells were co-treated with live B. cenocepacia bacteria and S. aureus supernatants (conditioned medium), the pro-inflammatory response was attenuated. This anti-inflammatory effect was widely exhibited in the S. aureus isolates tested and was mediated via reduced MAPK and NF-κB signalling, but not via IL-1 receptor or tumour necrosis factor receptor modulation. The staphylococcal effectors were characterized as small, heat-stable, non-proteinaceous and not cell wall-related factors.Conclusion. This study demonstrates for the first time the host response in a S. aureus/B. cenocepacia co-infection model and provides insight into a staphylococcal immune evasion mechanism, as well as a therapeutic intervention for excessive inflammation.
Collapse
Affiliation(s)
- Yuan Ji
- Department of Pharmacy and Pharmacology, University of Bath, BA2 7AY, UK
| | - Albert Bolhuis
- Department of Pharmacy and Pharmacology, University of Bath, BA2 7AY, UK
| | - Malcolm L Watson
- Department of Pharmacy and Pharmacology, University of Bath, BA2 7AY, UK
| |
Collapse
|
16
|
Staphylococcus aureus Colonization Induces Strain-Specific Suppression of Interleukin-17. Infect Immun 2018; 86:IAI.00834-17. [PMID: 29311230 DOI: 10.1128/iai.00834-17] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2017] [Accepted: 12/14/2017] [Indexed: 01/02/2023] Open
Abstract
Staphylococcus aureus is a pathogen that causes significant morbidity and mortality. Nasal carriage is a major source of transmission and of endogenous infection. Persistent carriage is detected in ∼30% of healthy individuals. While Th17 cells have been shown to play a role in S. aureus infection and clearance, the immune response to carriage is not well understood. Here, we evaluate the Th17 response and its potential inhibitors during S. aureus carriage. We recruited 25 volunteers, of whom 11 were persistent carriers. Volunteers' peripheral blood mononuclear cells (PBMCs) were stimulated with either their endogenous strain (a strain isolated from that carrier) or exogenous ones (strains not carried by that volunteer). Changes in Th17 cell frequency and numbers, interleukin-17 (IL-17) mRNA expression, and IL-17 protein abundance were measured by fluorescence-activated cell sorting, real-time PCR, and enzyme-linked immunosorbent assay. Similarly, responses of IL-17 suppressors (regulatory T cells [FOXP3], IL-10, IL-27, and IL-19) were measured. Th17 and IL-17 levels in response to stimulation with endogenous strains were significantly lower than those in response to stimulation with exogenous ones. Of the suppressive cytokines tested, only IL-19 exhibited a stronger response to endogenous than to exogenous strains. Addition of recombinant IL-19 to exogenous-strain-stimulated PBMCs caused decreased IL-17 expression, whereas addition of IL-19 antibodies to endogenous-strain-stimulated cells resulted in an increased IL-17 response. Together, our results suggest that S. aureus carriage induced a tolerogenic response to a carried strain that could be reproduced through the addition of recombinant IL-19 or prevented by the addition of IL-19 antibodies. This differential immune response may play a role in the determination of S. aureus carriage patterns.
Collapse
|
17
|
After the deluge: mining Staphylococcus aureus genomic data for clinical associations and host-pathogen interactions. Curr Opin Microbiol 2017; 41:43-50. [PMID: 29197673 DOI: 10.1016/j.mib.2017.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/04/2017] [Accepted: 11/16/2017] [Indexed: 01/31/2023]
Abstract
The genome of Staphylococcus aureus has rapidly become one the most frequently sequenced among bacteria, with more than 40000 genome sequences uploaded to public databases. Computational resources required for analysis and quality assessment have lagged behind accumulation of sequence data. Improved analytic pipelines, in combination with the development of customized S. aureus reference databases, can be used to inform S. aureus biology and potentially predict clinical outcome. Here, we review the currently available data about S. aureus genome in public databases, and discuss their potential utility for understanding S. aureus evolution. Also discussed are ways to overcome challenges to the application of whole-genome sequencing data for prevention and management of S. aureus disease.
Collapse
|
18
|
Schwartz JS, Peres AG, Mfuna Endam L, Cousineau B, Madrenas J, Desrosiers M. Topical probiotics as a therapeutic alternative for chronic rhinosinusitis: A preclinical proof of concept. Am J Rhinol Allergy 2017; 30:202-205. [PMID: 28124641 DOI: 10.2500/ajra.2016.30.4372] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Patients with chronic rhinosinusitis (CRS) have been shown to manifest a high inflammatory phenotype, with a sinus microbiome deficient in gram-positive bacteria. Gram-positive bacteria are capable of downregulating proinflammatory host responses via an interleukin (IL) 10 mediated response and may represent a potential therapeutic alternative for CRS. We wanted to (i) immunoprofile the IL-10 induction capacity of two gram-positive probiotic strains and (ii) verify the tolerance of these strains by the sinus epithelium. METHODS A peripheral blood mononuclear cell (PBMC) challenge model was used to document probiotic induction of IL-10 and tumor necrosis factor (TNF) alpha responses at various bacterial dilutions. Epithelial cell tolerance was demonstrated by using a primary epithelial cell model derived from patient biopsy specimens (six patients total [three with CRS and three controls]). After an incubation period with either a live or a heat-killed probiotic strain, cell viability was assessed by using light microscopy. RESULTS Both probiotic strains induced high IL-10 secretion in PBMCs, with differing profiles of TNF alpha production. Microscopic evaluation after probiotic incubation demonstrated intact cell viability for all cell cultures. CONCLUSION We identified well-tolerated, nonpathogenic, "generally recognized as safe" status gram-positive probiotics with anti-inflammatory properties. Topical probiotics represented a potential novel topical therapeutic strategy for CRS relevant for further clinical evaluation.
Collapse
Affiliation(s)
- Joseph S Schwartz
- Department of Otolaryngology, Head and Neck Surgery, McGill University, Montreal, Canada
| | | | | | | | | | | |
Collapse
|
19
|
Nemati M, Larussa T, Khorramdelazad H, Mahmoodi M, Jafarzadeh A. Toll-like receptor 2: An important immunomodulatory molecule during Helicobacter pylori infection. Life Sci 2017; 178:17-29. [PMID: 28427896 DOI: 10.1016/j.lfs.2017.04.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 04/06/2017] [Accepted: 04/11/2017] [Indexed: 12/11/2022]
Abstract
Toll like receptors (TLRs) are an essential subset of pathogen recognition receptors (PRRs) which identify the microbial components and contribute in the regulation of innate and adaptive immune responses against the infectious agents. The TLRs, especially TLR2, TLR4, TLR5 and TLR9, participate in the induction of immune response against H. pylori. TLR2 is expressed on a number of immune and non-immune cells and recognizes a vast broad of microbial components due to its potential to form heterodimers with other TLRs, including TLR1, TLR6 and TLR10. A number of H. pylori-related molecules may contribute to TLR2-dependent responses, including HP-LPS, HP-HSP60 and HP-NAP. TLR2 plays a pivotal role in regulation of immune response to H. pylori through activation of NF-κB and induction of cytokine expression in epithelial cells, monocytes/macrophages, dendritic cells, neutrophils and B cells. The TLR2-related immune response that is induced by H. pylori-derived components may play an important role regarding the outcome of the infection toward bacterial elimination, persistence or pathological reactions. The immunomodulatory and immunoregulatory roles of TLR2 during H. pylori infection were considered in this review. TLR2 could be considered as an interesting therapeutic target for treatment of H. pylori-related diseases.
Collapse
Affiliation(s)
- Maryam Nemati
- Department of Laboratory Sciences, School of Para-Medicine, Kerman University of Medical Sciences, Kerman, Iran; Department of Microbiology, School of Medicine, Islamic Azad University Branch of Kerman, Kerman, Iran
| | - Tiziana Larussa
- Department of Health Sciences, University of Catanzaro "Magna Graecia", 88100 Catanzaro, Italy
| | - Hossein Khorramdelazad
- Molecular Medicine Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran
| | - Merat Mahmoodi
- Department of Immunology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Abdollah Jafarzadeh
- Immunology of Infectious Diseases Research Center, Rafsanjan University of Medical Sciences, Rafsanjan, Iran; Department of Immunology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran; Department of Immunology, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
| |
Collapse
|
20
|
Klemm C, Bruchhagen C, van Krüchten A, Niemann S, Löffler B, Peters G, Ludwig S, Ehrhardt C. Mitogen-activated protein kinases (MAPKs) regulate IL-6 over-production during concomitant influenza virus and Staphylococcus aureus infection. Sci Rep 2017; 7:42473. [PMID: 28195157 PMCID: PMC5307969 DOI: 10.1038/srep42473] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 01/11/2017] [Indexed: 12/20/2022] Open
Abstract
Bacterial super-infections are a major complication of influenza virus (IV) infections and often lead to severe pneumonia. One hallmark of IV-associated Staphylococcus aureus (S. aureus) infection is rapid progression to a serious disease outcome. Changes in immune and inflammatory host responses increase morbidity and complicate efficient therapy. A key player during inflammation is the multifunctional cytokine IL-6. Although increased IL-6 levels have been observed after severe disease upon IV and/or bacterial super-infection, the underlying molecular mechanisms still remain to be elucidated. In the present study, we focused on cellular signalling pathways regulating IL-6 production upon IV/S. aureus super-infection. Additionally, infection with viable bacteria was mimicked by lipoteichoic acid stimulation in this model. Analyses of cellular signalling mechanisms revealed synergistically increased activation of the MAPK p38 as well as enhanced phosphorylation of the MAPKs ERK1/2 and JNK in the presence of super-infecting bacteria. Interestingly, inhibition of MAPK activity indicated a strong dependence of IL-6 expression on p38 and ERK1/2, while the MAPK JNK seems not to be involved. Thus, our results provide new molecular insights into the regulation of IL-6, a marker of severe disease, which might contribute to the lethal synergism of IV and S. aureus.
Collapse
Affiliation(s)
- Carolin Klemm
- Institute of Virology Muenster (IVM), Westfaelische Wilhelms-University Muenster, Von Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Christin Bruchhagen
- Institute of Virology Muenster (IVM), Westfaelische Wilhelms-University Muenster, Von Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Andre van Krüchten
- Institute of Virology Muenster (IVM), Westfaelische Wilhelms-University Muenster, Von Esmarch-Str. 56, D-48149 Muenster, Germany
| | - Silke Niemann
- Institute of Medical Microbiology, University Hospital of Muenster, Domagkstr, 10, D-48149 Muenster, Germany
| | - Bettina Löffler
- Institute of Medical Microbiology, University Hospital Jena, Erlanger Allee 101, D-07747 Jena, Germany
| | - Georg Peters
- Institute of Medical Microbiology, University Hospital of Muenster, Domagkstr, 10, D-48149 Muenster, Germany.,Cluster of Excellence Cells in Motion (CIM), University of Muenster, Muenster, Germany
| | - Stephan Ludwig
- Institute of Virology Muenster (IVM), Westfaelische Wilhelms-University Muenster, Von Esmarch-Str. 56, D-48149 Muenster, Germany.,Cluster of Excellence Cells in Motion (CIM), University of Muenster, Muenster, Germany
| | - Christina Ehrhardt
- Institute of Virology Muenster (IVM), Westfaelische Wilhelms-University Muenster, Von Esmarch-Str. 56, D-48149 Muenster, Germany.,Cluster of Excellence Cells in Motion (CIM), University of Muenster, Muenster, Germany
| |
Collapse
|
21
|
Leech JM, Lacey KA, Mulcahy ME, Medina E, McLoughlin RM. IL-10 Plays Opposing Roles during Staphylococcus aureus Systemic and Localized Infections. THE JOURNAL OF IMMUNOLOGY 2017; 198:2352-2365. [PMID: 28167629 DOI: 10.4049/jimmunol.1601018] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 01/12/2017] [Indexed: 01/08/2023]
Abstract
IL-10 is a potent anti-inflammatory mediator that plays a crucial role in limiting host immunopathology during bacterial infections by controlling effector T cell activation. Staphylococcus aureus has previously been shown to manipulate the IL-10 response as a mechanism of immune evasion during chronic systemic and biofilm models of infection. In the present study, we demonstrate divergent roles for IL-10 depending on the site of infection. During acute systemic S. aureus infection, IL-10 plays an important protective role and is required to prevent bacterial dissemination and host morbidity by controlling effector T cells and the associated downstream hyperactivation of inflammatory phagocytes, which are capable of host tissue damage. CD19+CD11b+CD5+ B1a regulatory cells were shown to rapidly express IL-10 in a TLR2-dependent manner in response to S. aureus, and adoptive transfer of B1a cells was protective during acute systemic infection in IL-10-deficient hosts. In contrast, during localized s.c. infection, IL-10 production plays a detrimental role by facilitating bacterial persistence via the same mechanism of controlling proinflammatory T cell responses. Our findings demonstrate that induction of IL-10 has a major influence on disease outcome during acute S. aureus infection. Too much IL-10 at one end of the scale may suppress otherwise protective T cell responses, thus facilitating persistence of the bacteria, and at the other end, too little IL-10 may tend toward fatal host-mediated pathology through excessive activation of T cells and associated phagocyte-mediated damage.
Collapse
Affiliation(s)
- John M Leech
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; and
| | - Keenan A Lacey
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; and
| | - Michelle E Mulcahy
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; and
| | - Eva Medina
- Infection Immunology Research Group, Helmholtz Center for Infection Research, 38124 Braunschweig, Germany
| | - Rachel M McLoughlin
- Host-Pathogen Interactions Group, School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland; and
| |
Collapse
|
22
|
Li Z, Levast B, Madrenas J. Staphylococcus aureusDownregulates IP-10 Production and Prevents Th1 Cell Recruitment. THE JOURNAL OF IMMUNOLOGY 2017; 198:1865-1874. [DOI: 10.4049/jimmunol.1601336] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 12/19/2016] [Indexed: 11/19/2022]
|
23
|
Bacteria isolated from lung modulate asthma susceptibility in mice. ISME JOURNAL 2017; 11:1061-1074. [PMID: 28045458 PMCID: PMC5437918 DOI: 10.1038/ismej.2016.181] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 11/03/2016] [Accepted: 11/11/2016] [Indexed: 12/12/2022]
Abstract
Asthma is a chronic, non-curable, multifactorial disease with increasing incidence in industrial countries. This study evaluates the direct contribution of lung microbial components in allergic asthma in mice. Germ-Free and Specific-Pathogen-Free mice display similar susceptibilities to House Dust Mice-induced allergic asthma, indicating that the absence of bacteria confers no protection or increased risk to aeroallergens. In early life, allergic asthma changes the pattern of lung microbiota, and lung bacteria reciprocally modulate aeroallergen responsiveness. Primo-colonizing cultivable strains were screened for their immunoregulatory properties following their isolation from neonatal lungs. Intranasal inoculation of lung bacteria influenced the outcome of allergic asthma development: the strain CNCM I 4970 exacerbated some asthma features whereas the pro-Th1 strain CNCM I 4969 had protective effects. Thus, we confirm that appropriate bacterial lung stimuli during early life are critical for susceptibility to allergic asthma in young adults.
Collapse
|
24
|
Hanzelmann D, Joo HS, Franz-Wachtel M, Hertlein T, Stevanovic S, Macek B, Wolz C, Götz F, Otto M, Kretschmer D, Peschel A. Toll-like receptor 2 activation depends on lipopeptide shedding by bacterial surfactants. Nat Commun 2016; 7:12304. [PMID: 27470911 PMCID: PMC4974576 DOI: 10.1038/ncomms12304] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 06/21/2016] [Indexed: 12/18/2022] Open
Abstract
Sepsis caused by Gram-positive bacterial pathogens is a major fatal disease but its molecular basis remains elusive. Toll-like receptor 2 (TLR2) has been implicated in the orchestration of inflammation and sepsis but its role appears to vary for different pathogen species and clones. Accordingly, Staphylococcus aureus clinical isolates differ substantially in their capacity to activate TLR2. Here we show that strong TLR2 stimulation depends on high-level production of phenol-soluble modulin (PSM) peptides in response to the global virulence activator Agr. PSMs are required for mobilizing lipoproteins, the TLR2 agonists, from the staphylococcal cytoplasmic membrane. Notably, the course of sepsis caused by PSM-deficient S. aureus is similar in wild-type and TLR2-deficient mice, but TLR2 is required for protection of mice against PSM-producing S. aureus. Thus, a crucial role of TLR2 depends on agonist release by bacterial surfactants. Modulation of this process may lead to new therapeutic strategies against Gram-positive infections. The role played by human protein TLR2 in inflammation and sepsis varies for different bacterial pathogens. Here, Hanzelmann et al. show that the differential abilities of Staphylococcus aureus strains to activate TLR2 depend on their production of peptides that release lipoproteins known to act as TLR2 agonists.
Collapse
Affiliation(s)
- Dennis Hanzelmann
- Department of Infection Biology, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Hwang-Soo Joo
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Mirita Franz-Wachtel
- Proteome Center Tübingen, Interfaculty Institute of Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Tobias Hertlein
- Institute for Molecular Infection Biology, University of Würzburg, Josef-Schneider-Straße 2, Würzburg 97080, Germany
| | - Stefan Stevanovic
- Department of Immunology, Interfaculty Institute for Cell Biology, Eberhard Karls University, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Boris Macek
- Proteome Center Tübingen, Interfaculty Institute of Cell Biology, University of Tübingen, Auf der Morgenstelle 15, 72076 Tübingen, Germany
| | - Christiane Wolz
- Department of Medical Microbiology and Hygiene, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Elfriede-Aulhorn-Straße 5, 72076 Tübingen, Germany
| | - Friedrich Götz
- Department of Microbial Genetics, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Michael Otto
- Pathogen Molecular Genetics Section, Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Dorothee Kretschmer
- Department of Infection Biology, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.,German Center for Infection Research, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| | - Andreas Peschel
- Department of Infection Biology, Interfaculty Institute for Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany.,German Center for Infection Research, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
| |
Collapse
|
25
|
Host-Bacterial Crosstalk Determines Staphylococcus aureus Nasal Colonization. Trends Microbiol 2016; 24:872-886. [PMID: 27474529 DOI: 10.1016/j.tim.2016.06.012] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 06/13/2016] [Accepted: 06/29/2016] [Indexed: 02/07/2023]
Abstract
Staphylococcus aureus persistently colonizes the anterior nares of approximately one fifth of the population and nasal carriage is a significant risk factor for infection. Recent advances have significantly refined our understanding of S. aureus-host communication during nasal colonization. Novel bacterial adherence mechanisms in the nasal epithelium have been identified, and novel roles for both the innate and the adaptive immune response in controlling S. aureus nasal colonization have been defined, through the use of both human and rodent models. It is clear that S. aureus maintains a unique, complex relationship with the host immune system and that S. aureus nasal colonization is overall a multifactorial process which is as yet incompletely understood.
Collapse
|
26
|
Rasid O, Cavaillon JM. Recent developments in severe sepsis research: from bench to bedside and back. Future Microbiol 2016; 11:293-314. [PMID: 26849633 DOI: 10.2217/fmb.15.133] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Severe sepsis remains a worldwide threat, not only in industrialized countries, due to their aging population, but also in developing countries where there still are numerous cases of neonatal and puerperal sepsis. Tools for early diagnosis, a prerequisite for rapid and appropriate antibiotic therapy, are still required. In this review, we highlight some recent developments in our understanding of the associated systemic inflammatory response that help deciphering pathophysiology (e.g., epigenetic, miRNA, regulatory loops, compartmentalization, apoptosis and synergy) and discuss some of the consequences of sepsis (e.g., immune status, neurological and muscular alterations). We also emphasize the challenge to better define animal models and discuss past failures in clinical investigations in order to define new efficient therapies.
Collapse
Affiliation(s)
- Orhan Rasid
- Unit Cytokines & Inflammation, Institut Pasteur, 28 rue Dr. Roux, Paris, France
| | - Jean-Marc Cavaillon
- Unit Cytokines & Inflammation, Institut Pasteur, 28 rue Dr. Roux, Paris, France
| |
Collapse
|
27
|
Immunomodulation and Disease Tolerance to Staphylococcus aureus. Pathogens 2015; 4:793-815. [PMID: 26580658 PMCID: PMC4693165 DOI: 10.3390/pathogens4040793] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 11/10/2015] [Indexed: 12/12/2022] Open
Abstract
The Gram-positive bacterium Staphylococcus aureus is one of the most frequent pathogens that causes severe morbidity and mortality throughout the world. S. aureus can infect skin and soft tissues or become invasive leading to diseases such as pneumonia, endocarditis, sepsis or toxic shock syndrome. In contrast, S. aureus is also a common commensal microbe and is often part of the human nasal microbiome without causing any apparent disease. In this review, we explore the immunomodulation and disease tolerance mechanisms that promote commensalism to S. aureus.
Collapse
|
28
|
Interactions of Klebsiella pneumoniae with the innate immune system vary in relation to clone and resistance phenotype. Antimicrob Agents Chemother 2015; 59:7036-43. [PMID: 26349819 DOI: 10.1128/aac.01405-15] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 08/30/2015] [Indexed: 11/20/2022] Open
Abstract
Apart from inadequate antimicrobial treatment, specific virulence factors contribute to the high attributable mortality of infections caused by multidrug-resistant (MDR) Klebsiella pneumoniae. We explored the roles of MDR and clones as virulence determinants of K. pneumoniae and their interaction with innate immunity. Twenty isolates were studied and characterized by resistance phenotype and multilocus sequence type (MLST). Human peripheral blood mononuclear cells (PBMCs) were stimulated for the production of proinflammatory cytokines by live and heat-killed isolates and plasmid DNA; modulation by cellular pathway inhibitors was explored. Survival of 30 mice was recorded after intraperitoneal challenge with susceptible and K. pneumoniae carbapenemase (KPC)-producing isolates. Splenocytes of mice were stimulated for the production of pro- and anti-inflammatory cytokines. Isolates were divided into different patterns of production of tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) poststimulation in relation to both the MLST clone and resistance phenotype. The sequence type 383 (ST383) clone producing Verona integron-encoded metallo-β-lactamase (VIM) stimulated high production of both TNF-α and IL-1β. Clone ST17 producing KPC elicited low TNF-α production; this was reversed by Toll-like receptor 9 (TLR9) antagonists, indicating an effect of plasmid DNA. This isolate was linked with early death of mice compared to high-TNF-α-producing isolates. We conclude that KPC-producing isolates seem to be highly virulent in a low-TNF-α-release environment, suggesting an immunoparalysis induction mechanism. KPC plasmids may directly contribute to the immune system stimulation.
Collapse
|
29
|
Ichimura M, Minami A, Nakano N, Kitagishi Y, Murai T, Matsuda S. Cigarette smoke may be an exacerbation factor in nonalcoholic fatty liver disease via modulation of the PI3K/AKT pathway. AIMS MOLECULAR SCIENCE 2015. [DOI: 10.3934/molsci.2015.4.427] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
|