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  1. Article ; Online: Gingival fibroblast activation by Porphyromonas gingivalis is driven by TLR2 and is independent of the LPS-TLR4 axis.

    Schuster, Aureliusz / Nieboga, Elwira / Kantorowicz, Malgorzata / Lipska, Weronika / Kaczmarzyk, Tomasz / Potempa, Jan / Grabiec, Aleksander M

    European journal of immunology

    2024  Volume 54, Issue 3, Page(s) e2350776

    Abstract: Gingival fibroblasts (GFs) are abundant structural cells of the periodontium that contribute to the host's innate immunity by producing cytokines and chemokines in response to oral pathogens, such as Porphyromonas gingivalis. Isolated lipopolysaccharide ( ...

    Abstract Gingival fibroblasts (GFs) are abundant structural cells of the periodontium that contribute to the host's innate immunity by producing cytokines and chemokines in response to oral pathogens, such as Porphyromonas gingivalis. Isolated lipopolysaccharide (Pg-LPS) is commonly used to study GF responses to P. gingivalis; however, this approach produced conflicting observations regarding its proinflammatory potential and the engagement of specific Toll-like receptors (TLRs). In this work, we demonstrate that commercially available Pg-LPS preparations are weak activators of GF innate immune responses compared with live P. gingivalis or other relevant virulence factors, such as P. gingivalis fimbriae or LPS from Escherichia coli. GF's nonresponsiveness to Pg-LPS can be only partly attributed to the low expression of TLR4 and its accessory molecules, CD14 and LY36, and is likely caused by the unique structure and composition of the Pg-LPS lipid A. Finally, we combined gene silencing and neutralizing antibody studies to demonstrate that GF response to infection with live P. gingivalis relies predominantly on TLR2. In contrast, the LPS-TLR4 signaling plays a negligible role in inflammatory cytokine production by GFs exposed to this oral pathogen, confirming that Pg-LPS stimulation is not an optimal model for studies of GF responses to P. gingivalis.
    MeSH term(s) Lipopolysaccharides ; Porphyromonas gingivalis ; Toll-Like Receptor 2/genetics ; Toll-Like Receptor 2/metabolism ; Toll-Like Receptor 4/metabolism ; Fibroblasts
    Chemical Substances Lipopolysaccharides ; Toll-Like Receptor 2 ; Toll-Like Receptor 4
    Language English
    Publishing date 2024-01-08
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 120108-6
    ISSN 1521-4141 ; 0014-2980
    ISSN (online) 1521-4141
    ISSN 0014-2980
    DOI 10.1002/eji.202350776
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Identification of a new genetic variant (G231N, E232T, N235D) of peptidylarginine deiminase from

    Bereta, Grzegorz P / Strzelec, Karolina / Łazarz-Bartyzel, Katarzyna / Dziedzic-Kowalska, Agata / Nowakowska, Zuzanna / Krutyhołowa, Anna / Bielecka, Ewa / Kantyka, Tomasz / Grabiec, Aleksander M / Kaczmarzyk, Tomasz / Chomyszyn-Gajewska, Maria / Potempa, Jan / Gawron, Katarzyna

    Frontiers in immunology

    2024  Volume 15, Page(s) 1355357

    Abstract: Chronic periodontitis (CP), an inflammatory disease of periodontal tissues driven by a dysbiotic subgingival bacterial biofilm, is also associated with several systemic diseases, including rheumatoid arthritis (RA). ...

    Abstract Chronic periodontitis (CP), an inflammatory disease of periodontal tissues driven by a dysbiotic subgingival bacterial biofilm, is also associated with several systemic diseases, including rheumatoid arthritis (RA).
    MeSH term(s) Humans ; Protein-Arginine Deiminases/genetics ; Protein-Arginine Deiminases/metabolism ; Porphyromonas gingivalis ; Peptides ; Periodontium/metabolism ; Chronic Periodontitis/genetics
    Chemical Substances Protein-Arginine Deiminases (EC 3.5.3.15) ; Peptides
    Language English
    Publishing date 2024-03-21
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2024.1355357
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Epigenetic regulation of inflammation in periodontitis: cellular mechanisms and therapeutic potential.

    Jurdziński, Krzysztof T / Potempa, Jan / Grabiec, Aleksander M

    Clinical epigenetics

    2020  Volume 12, Issue 1, Page(s) 186

    Abstract: Epigenetic mechanisms, namely DNA and histone modifications, are critical regulators of immunity and inflammation which have emerged as potential targets for immunomodulating therapies. The prevalence and significant morbidity of periodontitis, in ... ...

    Abstract Epigenetic mechanisms, namely DNA and histone modifications, are critical regulators of immunity and inflammation which have emerged as potential targets for immunomodulating therapies. The prevalence and significant morbidity of periodontitis, in combination with accumulating evidence that genetic, environmental and lifestyle factors cannot fully explain the susceptibility of individuals to disease development, have driven interest in epigenetic regulation as an important factor in periodontitis pathogenesis. Aberrant promoter methylation profiles of genes involved in inflammatory activation, including TLR2, PTGS2, IFNG, IL6, IL8, and TNF, have been observed in the gingival tissue, peripheral blood or buccal mucosa from patients with periodontitis, correlating with changes in expression and disease severity. The expression of enzymes that regulate histone acetylation, in particular histone deacetylases (HDACs), is also dysregulated in periodontitis-affected gingival tissue. Infection of gingival epithelial cells, gingival fibroblasts and periodontal ligament cells with the oral pathogens Porphyromonas gingivalis or Treponema denticola induces alterations in expression and activity of chromatin-modifying enzymes, as well as site-specific and global changes in DNA methylation profiles and in histone acetylation and methylation marks. These epigenetic changes are associated with excessive production of inflammatory cytokines, chemokines, and matrix-degrading enzymes that can be suppressed by small molecule inhibitors of HDACs (HDACi) or DNA methyltransferases. HDACi and inhibitors of bromodomain-containing BET proteins ameliorate inflammation, osteoclastogenesis, and alveolar bone resorption in animal models of periodontitis, suggesting their clinical potential as host modulation therapeutic agents. However, broader application of epigenomic methods will be required to create a comprehensive map of epigenetic changes in periodontitis. The integration of functional studies with global analyses of the epigenetic landscape will provide critical information on the therapeutic and diagnostic potential of epigenetics in periodontal disease.
    MeSH term(s) Animals ; Case-Control Studies ; CpG Islands ; Cytokines/metabolism ; DNA Methylation ; Epigenomics/methods ; Epithelial Cells/metabolism ; Epithelial Cells/microbiology ; Fibroblasts/metabolism ; Histone Code/genetics ; Histone Deacetylases/genetics ; Humans ; Inflammation/genetics ; Mice ; Models, Animal ; Periodontitis/epidemiology ; Periodontitis/genetics ; Periodontitis/pathology ; Periodontitis/therapy ; Porphyromonas gingivalis/genetics ; Porphyromonas gingivalis/isolation & purification ; Prevalence ; Promoter Regions, Genetic/genetics ; Proteins/antagonists & inhibitors ; Proteins/metabolism ; Rats ; Severity of Illness Index ; Treponema denticola/genetics ; Treponema denticola/isolation & purification
    Chemical Substances Cytokines ; Proteins ; bromodomain and extra-terminal domain protein, human ; Histone Deacetylases (EC 3.5.1.98)
    Language English
    Publishing date 2020-11-30
    Publishing country Germany
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2553921-8
    ISSN 1868-7083 ; 1868-7075
    ISSN (online) 1868-7083
    ISSN 1868-7075
    DOI 10.1186/s13148-020-00982-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Accessory fimbrial subunits and PPAD are necessary for TLR2 activation by Porphyromonas gingivalis.

    Wielento, Aleksandra / Bereta, Grzegorz P / Szczęśniak, Katarzyna / Jacuła, Anna / Terekhova, Marina / Artyomov, Maxim N / Hasegawa, Yoshiaki / Grabiec, Aleksander M / Potempa, Jan

    Molecular oral microbiology

    2023  Volume 38, Issue 4, Page(s) 334–346

    Abstract: Porphyromonas gingivalis is an oral pathogen that promotes dysbiosis by quenching the bactericidal activity of the host immune system while maintaining chronic inflammation, leading to periodontitis. This involves the secretion of virulence factors such ... ...

    Abstract Porphyromonas gingivalis is an oral pathogen that promotes dysbiosis by quenching the bactericidal activity of the host immune system while maintaining chronic inflammation, leading to periodontitis. This involves the secretion of virulence factors such as P. gingivalis peptidyl arginine deiminase (PPAD), which converts the C-terminal Arg residues of bacterial and host-derived proteins and peptides into citrulline. We have previously shown that PPAD activity and major fimbriae (containing FimA) are necessary for P. gingivalis to activate Toll-like receptor 2 (TLR2). TLR2 is an important component of the innate immune system and plays a predominant role in the recognition of P. gingivalis by host cells. Here, we extend those findings to show that P. gingivalis strains deficient for PPAD and fimbriae induced almost identical transcriptional profiles in infected primary human gingival fibroblasts (PHGFs), but these differed substantially from the transcriptome elicited by the wild-type ATCC 33277 strain. Apparently, PPAD-modified fimbriae trigger the host cell response to P. gingivalis, as confirmed by showing that the proinflammatory host cell response mediated by TLR2 is dependent on PPAD activity and the presence of fimbriae, with type I fimbriae as the most potent TLR2 activators. We also found that PPAD-modified accessory fimbrial subunits (FimC, FimD, and FimE) alone or in combination are TLR2 ligands in a reporter cell line. Although FimA polymerization to form the fimbrial shaft was not required for TLR2 activation, the secretion and proteolytic maturation of FimA were necessary for signaling by accessory Fim proteins. This was supported by showing that the proinflammatory activation of PHGFs is dependent on PPAD and accessory fimbrial subunits. We conclude that accessory fimbrial subunits are modified by PPAD and stimulate the response to P. gingivalis infection in a TLR2-dependent manner.
    MeSH term(s) Humans ; Protein-Arginine Deiminases/metabolism ; Porphyromonas gingivalis ; Toll-Like Receptor 2/genetics ; Toll-Like Receptor 2/metabolism ; Fimbriae, Bacterial/metabolism ; Gingiva/microbiology
    Chemical Substances Protein-Arginine Deiminases (EC 3.5.3.15) ; Toll-Like Receptor 2 ; TLR2 protein, human
    Language English
    Publishing date 2023-06-22
    Publishing country Denmark
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2537726-7
    ISSN 2041-1014 ; 2041-1006
    ISSN (online) 2041-1014
    ISSN 2041-1006
    DOI 10.1111/omi.12427
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: TLR2 Activation by

    Wielento, Aleksandra / Bereta, Grzegorz P / Łagosz-Ćwik, Katarzyna B / Eick, Sigrun / Lamont, Richard J / Grabiec, Aleksander M / Potempa, Jan

    Frontiers in immunology

    2022  Volume 13, Page(s) 823685

    Abstract: Porphyromonas ... ...

    Abstract Porphyromonas gingivalis
    MeSH term(s) Dinoprostone/metabolism ; Humans ; Periodontitis/metabolism ; Porphyromonas gingivalis ; Protein-Arginine Deiminases/metabolism ; Toll-Like Receptor 2/metabolism
    Chemical Substances TLR2 protein, human ; Toll-Like Receptor 2 ; Protein-Arginine Deiminases (EC 3.5.3.15) ; Dinoprostone (K7Q1JQR04M)
    Language English
    Publishing date 2022-04-01
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2606827-8
    ISSN 1664-3224 ; 1664-3224
    ISSN (online) 1664-3224
    ISSN 1664-3224
    DOI 10.3389/fimmu.2022.823685
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  6. Article: Epigenetic regulation in bacterial infections: targeting histone deacetylases

    Grabiec, Aleksander M / Potempa, Jan

    Critical reviews in microbiology. 2018 May 4, v. 44, no. 3

    2018  

    Abstract: Pathogens have developed sophisticated strategies to evade the immune response, among which manipulation of host cellular epigenetic mechanisms plays a prominent role. In the last decade, modulation of histone acetylation in host cells has emerged as an ... ...

    Abstract Pathogens have developed sophisticated strategies to evade the immune response, among which manipulation of host cellular epigenetic mechanisms plays a prominent role. In the last decade, modulation of histone acetylation in host cells has emerged as an efficient strategy of bacterial immune evasion. Virulence factors and metabolic products of pathogenic microorganisms alter expression and activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs) to suppress transcription of host defense genes through epigenetic changes in histone acetylation marks. This new avenue of pathogen–host interactions is particularly important in light of introduction of HDAC inhibitors into clinical practice. Considerable effort is currently being applied to better understand the effects of HDAC inhibitors on the quality of immune responses to pathogens and to characterize the therapeutic potential of these compounds in microbial infections. In this review, we will discuss the recently discovered mechanisms utilized by bacteria to facilitate their survival within infected hosts through subversion of the host acetylation system and the effects of acetylation modulators, including HDAC inhibitors and bromodomain-containing BET protein inhibitors, on innate immune responses against microbial pathogens. Integration of these two lines of experimental evidence provides critical information on the perspectives of epigenetic therapies targeting protein acetylation in infectious diseases.
    Keywords acetylation ; acetyltransferases ; bacteria ; bacterial infections ; epigenetics ; genes ; histone deacetylase ; histones ; host-pathogen relationships ; hosts ; immune evasion ; immune response ; innate immunity ; pathogens ; therapeutics ; transcription (genetics) ; virulence
    Language English
    Dates of publication 2018-0504
    Size p. 336-350.
    Publishing place Taylor & Francis
    Document type Article
    ZDB-ID 1053620-6
    ISSN 1549-7828 ; 1040-841X
    ISSN (online) 1549-7828
    ISSN 1040-841X
    DOI 10.1080/1040841X.2017.1373063
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Epigenetic regulation in bacterial infections: targeting histone deacetylases.

    Grabiec, Aleksander M / Potempa, Jan

    Critical reviews in microbiology

    2017  Volume 44, Issue 3, Page(s) 336–350

    Abstract: Pathogens have developed sophisticated strategies to evade the immune response, among which manipulation of host cellular epigenetic mechanisms plays a prominent role. In the last decade, modulation of histone acetylation in host cells has emerged as an ... ...

    Abstract Pathogens have developed sophisticated strategies to evade the immune response, among which manipulation of host cellular epigenetic mechanisms plays a prominent role. In the last decade, modulation of histone acetylation in host cells has emerged as an efficient strategy of bacterial immune evasion. Virulence factors and metabolic products of pathogenic microorganisms alter expression and activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs) to suppress transcription of host defense genes through epigenetic changes in histone acetylation marks. This new avenue of pathogen-host interactions is particularly important in light of introduction of HDAC inhibitors into clinical practice. Considerable effort is currently being applied to better understand the effects of HDAC inhibitors on the quality of immune responses to pathogens and to characterize the therapeutic potential of these compounds in microbial infections. In this review, we will discuss the recently discovered mechanisms utilized by bacteria to facilitate their survival within infected hosts through subversion of the host acetylation system and the effects of acetylation modulators, including HDAC inhibitors and bromodomain-containing BET protein inhibitors, on innate immune responses against microbial pathogens. Integration of these two lines of experimental evidence provides critical information on the perspectives of epigenetic therapies targeting protein acetylation in infectious diseases.
    MeSH term(s) Animals ; Bacteria/genetics ; Bacteria/metabolism ; Bacterial Infections/enzymology ; Bacterial Infections/genetics ; Bacterial Infections/metabolism ; Bacterial Infections/microbiology ; Epigenesis, Genetic ; Histone Deacetylase Inhibitors/metabolism ; Histone Deacetylases/genetics ; Histone Deacetylases/metabolism ; Host-Pathogen Interactions ; Humans
    Chemical Substances Histone Deacetylase Inhibitors ; Histone Deacetylases (EC 3.5.1.98)
    Language English
    Publishing date 2017-10-03
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 1053620-6
    ISSN 1549-7828 ; 1040-841X
    ISSN (online) 1549-7828
    ISSN 1040-841X
    DOI 10.1080/1040841X.2017.1373063
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Immunopathology of lung diseases: introduction for the special issue.

    Hussell, Tracy / Grabiec, Aleksander M

    Seminars in immunopathology

    2016  Volume 38, Issue 4, Page(s) 407–408

    MeSH term(s) Animals ; Cytokines/immunology ; Dendritic Cells/immunology ; Dendritic Cells/pathology ; Humans ; Immunity, Innate ; Killer Cells, Natural/immunology ; Killer Cells, Natural/pathology ; Lung Diseases/immunology ; Lung Diseases/pathology ; Lymphocytes/immunology ; Lymphocytes/pathology ; Macrophages/metabolism ; Macrophages/pathology
    Chemical Substances Cytokines
    Keywords covid19
    Language English
    Publishing date 2016-05-19
    Publishing country Germany
    Document type Editorial
    ZDB-ID 2316828-6
    ISSN 1863-2300 ; 1863-2297
    ISSN (online) 1863-2300
    ISSN 1863-2297
    DOI 10.1007/s00281-016-0572-2
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  9. Article ; Online: The role of airway macrophages in apoptotic cell clearance following acute and chronic lung inflammation.

    Grabiec, Aleksander M / Hussell, Tracy

    Seminars in immunopathology

    2016  Volume 38, Issue 4, Page(s) 409–423

    Abstract: Acute and chronic inflammatory responses in the lung are associated with the accumulation of large quantities of immune and structural cells undergoing apoptosis, which need to be engulfed by phagocytes in a process called 'efferocytosis'. Apoptotic cell ...

    Abstract Acute and chronic inflammatory responses in the lung are associated with the accumulation of large quantities of immune and structural cells undergoing apoptosis, which need to be engulfed by phagocytes in a process called 'efferocytosis'. Apoptotic cell recognition and removal from the lung is mediated predominantly by airway macrophages, though immature dendritic cells and non-professional phagocytes, such as epithelial cells and mesenchymal cells, can also display this function. Efficient clearance of apoptotic cells from the airways is essential for successful resolution of inflammation and the return to lung homeostasis. Disruption of this process leads to secondary necrosis of accumulating apoptotic cells, release of necrotic cell debris and subsequent uncontrolled inflammatory activation of the innate immune system by the released 'damage associated molecular patterns' (DAMPS). To control the duration of the immune response and prevent autoimmune reactions, anti-inflammatory signalling cascades are initiated in the phagocyte upon apoptotic cell uptake, mediated by a range of receptors that recognise specific phospholipids or proteins externalised on, or secreted by, the apoptotic cell. However, prolonged activation of apoptotic cell recognition receptors, such as the family of receptor tyrosine kinases Tyro3, Axl and MerTK (TAM), may delay or prevent inflammatory responses to subsequent infections. In this review, we will discuss recent advances in our understanding of the mechanism controlling apoptotic cell recognition and removal from the lung in homeostasis and during inflammation, the contribution of defective efferocytosis to chronic inflammatory lung diseases, such as chronic obstructive pulmonary disease, asthma and cystic fibrosis, and implications of the signals triggered by apoptotic cells in the susceptibility to pulmonary microbial infections.
    MeSH term(s) Acute Disease ; Animals ; Apoptosis/immunology ; Biomarkers ; Cell Communication/immunology ; Chronic Disease ; Humans ; Immunity ; Inflammation/etiology ; Inflammation/immunology ; Inflammation/metabolism ; Inflammation/pathology ; Lung Diseases/etiology ; Lung Diseases/immunology ; Lung Diseases/metabolism ; Lung Diseases/pathology ; Macrophages/immunology ; Macrophages/metabolism ; Phagocytosis/immunology ; Receptors, Cell Surface/metabolism ; Signal Transduction
    Chemical Substances Biomarkers ; Receptors, Cell Surface
    Keywords covid19
    Language English
    Publishing date 2016-03-08
    Publishing country Germany
    Document type Journal Article ; Review
    ZDB-ID 2316828-6
    ISSN 1863-2300 ; 1863-2297
    ISSN (online) 1863-2300
    ISSN 1863-2297
    DOI 10.1007/s00281-016-0555-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Culture of Human Monocyte-Derived Macrophages.

    Kelly, Aoife / Grabiec, Aleksander M / Travis, Mark A

    Methods in molecular biology (Clifton, N.J.)

    2018  Volume 1784, Page(s) 1–11

    Abstract: The study of human macrophages is often hampered by access to tissue and inability of this cell type to survive in vitro following isolation. The culture of human monocyte-derived macrophages (MDMs) represents a tool to study macrophages, with monocytes ... ...

    Abstract The study of human macrophages is often hampered by access to tissue and inability of this cell type to survive in vitro following isolation. The culture of human monocyte-derived macrophages (MDMs) represents a tool to study macrophages, with monocytes known to give rise to tissue macrophages influenced by certain environmental cues. Here we describe a method of culturing monocyte-derived macrophages from CD14+ blood monocytes and polarization toward different macrophage phenotypes.
    MeSH term(s) Cell Culture Techniques/methods ; Cell Differentiation/genetics ; Humans ; Lipopolysaccharide Receptors/genetics ; Macrophages/cytology ; Molecular Biology/methods ; Monocytes/cytology
    Chemical Substances Lipopolysaccharide Receptors
    Language English
    Publishing date 2018-05-18
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-4939-7837-3_1
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