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Claesson R, Chiang HM, Lindholm M, Höglund Åberg C, Haubek D, Johansson A, Oscarsson J. Characterization of Aggregatibacter actinomycetemcomitans Serotype b Strains with Five Different, Including Two Novel, Leukotoxin Promoter Structures. Vaccines (Basel) 2020; 8:vaccines8030398. [PMID: 32698444 PMCID: PMC7563764 DOI: 10.3390/vaccines8030398] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 01/23/2023] Open
Abstract
The JP2 genotype of A. actinomycetemcomitans, serotype b has attracted much interest during the past three decades due to its close association with periodontitis in young individuals and the enhanced expression of a leukotoxin (LtxA). A typical feature of this genotype is a 530-base pair (bp) deletion in the ltxCABD promoter region controlling leukotoxin expression. In the present work, we have characterized serotype b strains with four additional promoter types. Two novel types have been recognized, that is, one with a 230-bp deletion and one with a 172-bp duplication. Moreover, a strain with a 640-bp deletion and three strains with a full-length promoter, including the type strain Y4, were included in the present study. The seven strains were characterized by multi locus sequence typing (MLST) and arbitrarily primed polymerase chain reaction (PCR) and assessed for LtxA production. MLST showed that the strains with the non-JP2-like deletions represented distinct monophyletic groups, whereas the JP2 strain, HK1651, represented a separate branch. LtxA production was high in all three strains with a promoter deletion, whereas the other four strains showed significantly lower levels. It can be concluded that the genetic characterization and determination of LtxA production of A. actinomycetemcomitans isolates from individuals with periodontitis can contribute to the identification of novel virulent genotypes of this bacterium.
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Affiliation(s)
- Rolf Claesson
- Division of Oral Microbiology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (M.L.); (J.O.)
- Correspondence:
| | - Huei-Min Chiang
- Division of Molecular Periodontology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (H.-M.C.); (C.H.Å.); (A.J.)
| | - Mark Lindholm
- Division of Oral Microbiology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (M.L.); (J.O.)
| | - Carola Höglund Åberg
- Division of Molecular Periodontology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (H.-M.C.); (C.H.Å.); (A.J.)
| | - Dorte Haubek
- Section for Paediatric Dentistry, Department of Dentistry and Oral Health, Aarhus University, 8000 Aarhus, Denmark;
| | - Anders Johansson
- Division of Molecular Periodontology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (H.-M.C.); (C.H.Å.); (A.J.)
| | - Jan Oscarsson
- Division of Oral Microbiology, Department of Odontology, Umeå University, S-90187 Umeå, Sweden; (M.L.); (J.O.)
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2
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Lindholm M, Metsäniitty M, Granström E, Oscarsson J. Outer membrane vesicle-mediated serum protection in Aggregatibacter actinomycetemcomitans. J Oral Microbiol 2020; 12:1747857. [PMID: 32363008 PMCID: PMC7178816 DOI: 10.1080/20002297.2020.1747857] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 01/23/2023] Open
Abstract
Aggregatibacter actinomycetemcomitans belongs to the HACEK group of fastidious Gram-negative organisms, a recognized cause of infective endocarditis. A. actinomycetemcomitans is also implicated in periodontitis, with rapid progress in adolescents. We recently demonstrated that the major outer membrane protein, OmpA1 was critical for serum survival of the A. actinomycetemcomitans serotype a model strain, D7SS, and that the paralogue, OmpA2 could operate as a functional homologue to OmpA1 in mediating serum resistance. In the present work, an essentially serum-sensitive ompA1 ompA2 double mutant A. actinomycetemcomitans strain derivative was exploited to elucidate if A. actinomycetemcomitans OMVs can contribute to bacterial serum resistance. Indeed, supplementation of OMVs resulted in a dose-dependent increase of the survival of the serum-sensitive strain in incubations in 50% normal human serum (NHS). Whereas neither OmpA1 nor OmpA2 was required for the OMV-mediated serum protection, OMVs and LPS from an A. actinomycetemcomitans strain lacking the LPS O-antigen polysaccharide part were significantly impaired in protecting D7SS ompA1 ompA2. Our results using a complement system screen assay support a model where A. actinomycetemcomitans OMVs can act as a decoy, which can trigger complement activation in an LPS-dependent manner, and consume complement components to protect serum-susceptible bacterial cells.
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Affiliation(s)
- Mark Lindholm
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | - Marjut Metsäniitty
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | | | - Jan Oscarsson
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
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3
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Belibasakis GN, Maula T, Bao K, Lindholm M, Bostanci N, Oscarsson J, Ihalin R, Johansson A. Virulence and Pathogenicity Properties of Aggregatibacter actinomycetemcomitans. Pathogens 2019; 8:E222. [PMID: 31698835 PMCID: PMC6963787 DOI: 10.3390/pathogens8040222] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/29/2019] [Accepted: 11/04/2019] [Indexed: 02/06/2023] Open
Abstract
Aggregatibacter actinomycetemcomitans is a periodontal pathogen colonizing the oral cavity of a large proportion of the human population. It is equipped with several potent virulence factors that can cause cell death and induce or evade inflammation. Because of the large genetic diversity within the species, both harmless and highly virulent genotypes of the bacterium have emerged. The oral condition and age, as well as the geographic origin of the individual, influence the risk to be colonized by a virulent genotype of the bacterium. In the present review, the virulence and pathogenicity properties of A. actinomycetemcomitans will be addressed.
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Affiliation(s)
- Georgios N. Belibasakis
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, S-141 04 Huddinge, Sweden; (G.N.B.); (K.B.); (N.B.)
| | - Terhi Maula
- Department of Biochemistry, University of Turku, FI-20014 Turku, Finland; (T.M.); (R.I.)
| | - Kai Bao
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, S-141 04 Huddinge, Sweden; (G.N.B.); (K.B.); (N.B.)
| | - Mark Lindholm
- Department of Odontology, Umeå University, S-901 87 Umeå, Sweden; (M.L.); (J.O.)
| | - Nagihan Bostanci
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, S-141 04 Huddinge, Sweden; (G.N.B.); (K.B.); (N.B.)
| | - Jan Oscarsson
- Department of Odontology, Umeå University, S-901 87 Umeå, Sweden; (M.L.); (J.O.)
| | - Riikka Ihalin
- Department of Biochemistry, University of Turku, FI-20014 Turku, Finland; (T.M.); (R.I.)
| | - Anders Johansson
- Department of Odontology, Umeå University, S-901 87 Umeå, Sweden; (M.L.); (J.O.)
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4
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Johansson A, Claesson R, Höglund Åberg C, Haubek D, Lindholm M, Jasim S, Oscarsson J. Genetic Profiling of Aggregatibacter actinomycetemcomitans Serotype B Isolated from Periodontitis Patients Living in Sweden. Pathogens 2019; 8:pathogens8030153. [PMID: 31533208 PMCID: PMC6789814 DOI: 10.3390/pathogens8030153] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/10/2019] [Accepted: 09/15/2019] [Indexed: 02/06/2023] Open
Abstract
The bacterium Aggregatibacter actinomycetemcomitans is associated with aggressive forms of periodontitis and with systemic diseases, such as endocarditis. By assessing a Ghanaian longitudinal adolescent cohort, we earlier recognized the cagE gene as a possible diagnostic marker for a subgroup of JP2 and non-JP2 genotype serotype b A. actinomycetemcomitans strains, associated with high leukotoxicity as determined in a semi-quantitative cell assay. This group of A. actinomycetemcomitans is associated with the progression of attachment loss. In the present work, we used conventional polymerase chain reaction (PCR) and quantitative PCR to perform the cagE genotyping of our collection of 116 selected serotype b A. actinomycetemcomitans strains, collected over a period of 15 years from periodontitis patients living in Sweden. The A. actinomycetemcomitans strains carrying cagE (referred to as cagE+; n = 49) were compared to the cagE-negative strains (n = 67), present at larger proportions in the subgingival plaque samples, and were also much more prevalent in the young (≤35 years) compared to in the old (>35 years) group of patients. Our present results underline the potential use of cagE genotyping in the risk assessment of the development of periodontal attachment loss in Swedish adolescents.
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Affiliation(s)
- Anders Johansson
- Division of Molecular Periodontology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden
| | - Rolf Claesson
- Division of Oral Microbiology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden
| | - Carola Höglund Åberg
- Division of Molecular Periodontology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden
| | - Dorte Haubek
- Section for Pediatric Dentistry, Department of Dentistry and Oral Health, Aarhus University, 8000 Aarhus, Denmark
| | - Mark Lindholm
- Division of Oral Microbiology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden
| | - Sarah Jasim
- Division of Oral Microbiology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden
| | - Jan Oscarsson
- Division of Oral Microbiology, Department of Odontology, Umeå University, 907 00 Umeå, Sweden.
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5
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Nice JB, Balashova NV, Kachlany SC, Koufos E, Krueger E, Lally ET, Brown AC. Aggregatibacter actinomycetemcomitans Leukotoxin Is Delivered to Host Cells in an LFA-1-Indepdendent Manner When Associated with Outer Membrane Vesicles. Toxins (Basel) 2018; 10:toxins10100414. [PMID: 30322160 PMCID: PMC6215133 DOI: 10.3390/toxins10100414] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/08/2018] [Accepted: 10/10/2018] [Indexed: 12/21/2022] Open
Abstract
The Gram-negative bacterium, Aggregatibacter actinomycetemcomitans, has been associated with localized aggressive periodontitis (LAP). In particular, highly leukotoxic strains of A. actinomycetemcomitans have been more closely associated with this disease, suggesting that LtxA is a key virulence factor for A. actinomycetemcomitans. LtxA is secreted across both the inner and outer membranes via the Type I secretion system, but has also been found to be enriched within outer membrane vesicles (OMVs), derived from the bacterial outer membrane. We have characterized the association of LtxA with OMVs produced by the highly leukotoxic strain, JP2, and investigated the interaction of these OMVs with host cells to understand how LtxA is delivered to host cells in this OMV-associated form. Our results demonstrated that a significant fraction of the secreted LtxA exists in an OMV-associated form. Furthermore, we have discovered that in this OMV-associated form, the toxin is trafficked to host cells by a cholesterol- and receptor-independent mechanism in contrast to the mechanism by which free LtxA is delivered. Because OMV-associated toxin is trafficked to host cells in an entirely different manner than free toxin, this study highlights the importance of studying both free and OMV-associated forms of LtxA to understand A. actinomycetemcomitans virulence.
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Affiliation(s)
- Justin B Nice
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015, USA.
| | - Nataliya V Balashova
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA.
| | - Scott C Kachlany
- Department of Oral Biology, Rutgers University School of Dental Medicine, Newark, NJ 07101, USA.
| | - Evan Koufos
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015, USA.
| | - Eric Krueger
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015, USA.
| | - Edward T Lally
- Department of Pathology, University of Pennsylvania School of Dental Medicine, Philadelphia, PA 19104, USA.
| | - Angela C Brown
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA 18015, USA.
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6
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Ihalin R, Eneslätt K, Asikainen S. Peptidoglycan-associated lipoprotein of Aggregatibacter actinomycetemcomitans induces apoptosis and production of proinflammatory cytokines via TLR2 in murine macrophages RAW 264.7 in vitro. J Oral Microbiol 2018; 10:1442079. [PMID: 29686780 PMCID: PMC5907638 DOI: 10.1080/20002297.2018.1442079] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 02/14/2018] [Indexed: 11/25/2022] Open
Abstract
Peptidoglycan-associated lipoprotein (PAL) is a conserved pro-inflammatory outer membrane lipoprotein in Gram-negative bacteria. Compared to systemic pathogens, little is known about the virulence properties of PAL in Aggregatibacter actinomycetemcomitans (AaPAL). The aims of this study were to investigate the cytolethality of AaPAL and its ability to induce pro-inflammatory cytokine production in macrophages. Mouse macrophages were stimulated with AaPAL, and the production of IL-1β, IL-6, TNF-α, and MCP-1 was measured after 6, 24, and 48 h. To investigate which receptor AaPAL employs for its interaction with macrophages, anti-toll-like receptor (TLR)2 and anti-TLR4 antibodies were used to block respective TLRs on macrophages. Metabolic activity and apoptosis of the macrophages were investigated after stimulation with AaPAL. AaPAL induced the production of MCP-1, TNF-α, IL-6, and IL-1β from mouse macrophages in order of decreasing abundance. The pre-treatment of macrophages with an anti-TLR2 antibody significantly diminished cytokine production. Under AaPAL stimulation, the metabolic activity of macrophages decreased in a dose- and time-dependent manner. Furthermore, AaPAL induced apoptosis in 56% of macrophages after 48 h of incubation. Our data suggest that AaPAL can kill macrophages by apoptosis. The results also emphasize the role of AaPAL as a potent pro-inflammatory agent in A. actinomycetemcomitans-associated infections.
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Affiliation(s)
- Riikka Ihalin
- Department of Odontology, Oral Microbiology, Umeå University, Umeå, Sweden.,Department of Biochemistry, University of Turku, Turku, Finland
| | - Kjell Eneslätt
- Department of Odontology, Oral Microbiology, Umeå University, Umeå, Sweden
| | - Sirkka Asikainen
- Department of Odontology, Oral Microbiology, Umeå University, Umeå, Sweden
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7
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Henderson B, Kaiser F. Bacterial modulators of bone remodeling in the periodontal pocket. Periodontol 2000 2017; 76:97-108. [DOI: 10.1111/prd.12160] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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8
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Llama-Palacios A, Potupa O, Sánchez MC, Figuero E, Herrera D, Sanz M. Aggregatibacter actinomycetemcomitans Growth in Biofilm versus Planktonic State: Differential Expression of Proteins. J Proteome Res 2017; 16:3158-3167. [PMID: 28707473 DOI: 10.1021/acs.jproteome.7b00127] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aggregatibacter actinomycetemcomitans (Aa) is a pathogenic bacterium residing in the subgingival plaque biofilm strongly associated with the pathogenesis of periodontitis. The aim of this investigation was to study the protein differential expression of Aa when growing on biofilm compared with planktonic state using proteomic analysis by the 2D-DIGE system. Eighty-seven proteins were differentially expressed during biofilm growth (1.5-fold, p < 0.05), with 13 overexpressed and 37 down-expressed. Those repressed were mainly proteins involved in metabolism, biosynthesis, and transport. The overexpressed proteins were outer membrane proteins (OMPs) and highly immunogenic proteins such as YaeT (OMP), FtsZ, OMP39, OMP18/16, the chaperone GroEL, OMPA, adenylate kinase (Adk), and dihydrolipoamide acetyltransferase. The enrichment fractions of the OMPs from biofilm and planktonic states were obtained, and these proteins were analyzed by Western blotting with human serum from a periodontitis patient and one healthy control. These immunogenic proteins overexpressed in the biofilm may represent candidate virulence factors.
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Affiliation(s)
- Arancha Llama-Palacios
- Oral Microbiology Laboratory at the Faculty of Odontology, University Complutense , Madrid 28040, Spain
| | - Oksana Potupa
- Oral Microbiology Laboratory at the Faculty of Odontology, University Complutense , Madrid 28040, Spain
| | - María C Sánchez
- Oral Microbiology Laboratory at the Faculty of Odontology, University Complutense , Madrid 28040, Spain
| | - Elena Figuero
- ETEP (Etiology and Therapy of Periodontal Diseases) Research Group, University Complutense , Madrid 28040, Spain
| | - David Herrera
- ETEP (Etiology and Therapy of Periodontal Diseases) Research Group, University Complutense , Madrid 28040, Spain
| | - Mariano Sanz
- ETEP (Etiology and Therapy of Periodontal Diseases) Research Group, University Complutense , Madrid 28040, Spain
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Aggregatibacter actinomycetemcomitans regulates the expression of integrins and reduces cell adhesion via integrin α5 in human gingival epithelial cells. Mol Cell Biochem 2017; 436:39-48. [PMID: 28593565 DOI: 10.1007/s11010-017-3076-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/25/2017] [Indexed: 01/06/2023]
Abstract
Gingival epithelial cells form a physiological barrier against bacterial invasion. Excessive bacterial invasion destroys the attachment between the tooth surface and the epithelium, resulting in periodontitis. Integrins play a significant role in cell attachment; therefore, we hypothesized that bacterial infection might decrease the expressions of these integrins in gingival epithelial cells, resulting in reduced cell adhesion. Immortalized human gingival epithelial cells were co-cultured with Aggregatibacter actinomycetemcomitans Y4 (Aa Y4), and the gene expression levels of IL-8, proliferating cell nuclear antigen (PCNA), and integrins (α2, α3, α5, β4, and β6) were measured using quantitative reverse transcription polymerase chain reaction. Expression of PCNA and integrins, except integrin α5, was significantly downregulated, while expression of IL-8 and integrin α5 was significantly upregulated in the cells co-cultured with Aa Y4. The number of adherent cells significantly decreased when co-cultured with Aa Y4, as determined using cell adhesion assays. In the cells co-cultured with Aa Y4 and an integrin α5 neutralizing antibody, there was no effect on the expression of IL-8 and PCNA, while the expressions of integrins α2, α3, β4, and β6, and the number of adherent cells did not decrease. The number of invading bacteria in the cells was reduced in the presence of the antibody and increased in the presence of TLR2/4 inhibitor. Therefore, integrin α5 might be involved in Aa Y4 invasion into gingival epithelial cells, and the resulting signal transduction cascade reduces cell adhesion by decreasing the expression of integrins, while the TLR2/4 signaling cascade regulates IL-8 expression.
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10
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Johansson A, Claesson R, Höglund Åberg C, Haubek D, Oscarsson J. ThecagEgene sequence as a diagnostic marker to identify JP2 and non-JP2 highly leukotoxicAggregatibacter actinomycetemcomitansserotype b strains. J Periodontal Res 2017; 52:903-912. [DOI: 10.1111/jre.12462] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2017] [Indexed: 12/27/2022]
Affiliation(s)
- A. Johansson
- Division of Molecular Periodontology; Department of Odontology; Umeå University; Umeå Sweden
| | - R. Claesson
- Division of Oral Microbiology; Department of Odontology; Umeå University; Umeå Sweden
| | - C. Höglund Åberg
- Division of Molecular Periodontology; Department of Odontology; Umeå University; Umeå Sweden
| | - D. Haubek
- Section for Pediatric Dentistry; Department of Dentistry and Oral Health; Aarhus University; Aarhus Denmark
| | - J. Oscarsson
- Division of Oral Microbiology; Department of Odontology; Umeå University; Umeå Sweden
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11
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Lakio L, Lehto M, Tuomainen AM, Jauhiainen M, Malle E, Asikainen S, Pussinen PJ. Pro-atherogenic properties of lipopolysaccharide from the periodontal pathogen Actinobacillus actinomycetemcomitans. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/09680519060120010601] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
An association between cardiovascular and periodontal disease may be due to lipopolysaccharide (LPS)-promoted release of inflammatory mediators, adverse alterations of the lipoprotein profile, and an imbalance in cholesterol homeostasis. Since periodontopathogenic potential differs between serotypes of a major periodontal pathogen, Actinobacillus actinomycetemcomitans, we studied the pro-atherogenic properties of LPS preparations from serotypes b and d strains on macrophages (RAW 264.7). A. actinomycetemcomitans LPS preparations induced a time-dependent release of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). LPS induced foam cell formation and cholesteryl ester accumulation from native low density lipoprotein in the following order: A. actinomycetemcomitans strains JP2 (serotype b) > Y4 (serotype b) > IDH781 (serotype d). mRNA expression levels of scavenger receptor class B, type-I, and ATP-binding cassette transporter-1, receptors mediating cholesterol efflux from macrophages, were decreased by LPS preparations. The results suggest that the pro-atherogenic potential of A. actinomycetemcomitans LPS may depend on the infecting strain and correlate with the periodontopathogenic potential of the pathogen.
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Affiliation(s)
- Laura Lakio
- Institute of Dentistry, University of Helsinki, and Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, Helsinki, Finland
| | - Markku Lehto
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
| | - Anita M. Tuomainen
- Institute of Dentistry, University of Helsinki, and Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, Helsinki, Finland
| | - Matti Jauhiainen
- Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland
| | - Ernst Malle
- Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University Graz, Graz, Austria
| | - Sirkka Asikainen
- Section of Oral Microbiology, Institute of Odontology, UmeÅ University, UmeÅ, Sweden
| | - Pirkko J. Pussinen
- Institute of Dentistry, University of Helsinki, and Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, Helsinki, Finland,
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12
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Lipopolysaccharide derived from Aggregatibacter actinomycetemcomitans inhibits differentiation of osteoblasts. PEDIATRIC DENTAL JOURNAL 2014. [DOI: 10.1016/j.pdj.2014.03.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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Armitage GC. Learned and unlearned concepts in periodontal diagnostics: a 50-year perspective. Periodontol 2000 2014; 62:20-36. [PMID: 23574462 DOI: 10.1111/prd.12006] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the past 50 years, conceptual changes in the field of periodontal diagnostics have paralleled those associated with a better scientific understanding of the full spectrum of processes that affect periodontal health and disease. Fifty years ago, concepts regarding the diagnosis of periodontal diseases followed the classical pathology paradigm. It was believed that the two basic forms of destructive periodontal disease were chronic inflammatory periodontitis and 'periodontosis'- a degenerative condition. In the subsequent 25 years it was shown that periodontosis was an infection. By 1987, major new concepts regarding the diagnosis and pathogenesis of periodontitis included: (i) all cases of untreated gingivitis do not inevitably progress to periodontitis; (ii) progression of untreated periodontitis is often episodic; (iii) some sites with untreated periodontitis do not progress; (iv) a rather small population of specific bacteria ('periodontal pathogens') appear to be the main etiologic agents of chronic inflammatory periodontitis; and (v) tissue damage in periodontitis is primarily caused by inflammatory and immunologic host responses to infecting agents. The concepts that were in place by 1987 are still largely intact in 2012. However, in the decades to come, it is likely that new information on the human microbiome will change our current concepts concerning the prevention, diagnosis and treatment of periodontal diseases.
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14
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Leukocyte production of inflammatory mediators is inhibited by the antioxidants phloretin, silymarin, hesperetin, and resveratrol. Mediators Inflamm 2014; 2014:938712. [PMID: 24707119 PMCID: PMC3953573 DOI: 10.1155/2014/938712] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 01/09/2014] [Accepted: 01/11/2014] [Indexed: 12/18/2022] Open
Abstract
Antioxidants possess significant therapeutic potential for the treatment of inflammatory disorders. One such disorder is periodontitis characterised by an antimicrobial immune response, inflammation, and irreversible changes to the supporting structures of the teeth. Recognition of conserved pathogen-associated molecular patterns is a crucial component of innate immunity to Gram-negative bacteria such as Escherichia coli, as well as the periodontal pathogen Aggregatibacter actinomycetemcomitans. In this study, we investigated the antioxidants Phloretin, Silymarin, Hesperetin, and Resveratrol to ascertain whether they altered the production of inflammatory mediators by innately-activated leukocytes. Peripheral blood mononuclear cells were stimulated with lipopolysaccharide purified from Aggregatibacter actinomycetemcomitans, and the production of cytokines, chemokines, and differentiation factors was assayed by enzyme-linked immunosorbent assay, cytometric bead array, and RT-PCR. Significant inhibition of these factors was achieved upon treatment with Phloretin, Silymarin, Hesperetin, and Resveratrol. These data further characterise the potent anti-inflammatory properties of antioxidants. Their ability to inhibit the production of inflammatory cytokines, chemokines, and differentiation factors by a heterogeneous population of leukocytes has clear implications for their therapeutic potential in vivo.
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15
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Miyagawa T, Fujita T, Ouhara K, Matsuda S, Kajiya M, Hayashida K, Imai H, Yoshimoto T, Iwata T, Shiba H, Abiko Y, Kurihara H. Irsogladine maleate regulates the inflammatory related genes in human gingival epithelial cells stimulated by Aggregatibacter actinomycetemcomitans. Int Immunopharmacol 2013; 15:340-7. [PMID: 23306101 DOI: 10.1016/j.intimp.2012.12.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 12/08/2012] [Accepted: 12/21/2012] [Indexed: 10/27/2022]
Abstract
Periodontitis is an infectious inflammatory disease. Our previous studies have revealed that irsogladine maleate (IM) regulates intercellular junctional function and chemokine secretion in gingival epithelium, resulting in the suppression of the onset of periodontal disease in a rat model. Therefore, it is plausible that IM is a promising preventive remedy for periodontal disease. In this study, to gain a better understanding of IM in gingival epithelial cells, we employed a DNA microarray analysis. More specifically, human gingival epithelial cells (HGEC) were exposed to Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) in the presence or absence of IM. Then, a human genome focus array was used. A. actinomycetemcomitans facilitated the expression of several inflammatory-related genes, including these for matrix metalloproteinase (MMP)-3, interleukin (IL)-6, and intercellular adhesion molecule-1 (ICAM-1) in HGEC, while these mRNA levels were attenuated by IM treatment. Importantly, consistent with mRNA levels, immunoblotting, immunofluorescence staining and ELISA analysis indicated that IM also abrogated the A. actinomycetemcomitans-induced increase in MMP-3, IL-6, and ICAM-1 at the protein level. In addition, inhibition of the ERK or p38 MAP kinase signaling cascade, previously reported to be disturbed by IM treatment in HGEC, clearly blocked A. actinomycetemcomitans-induced MMP-3, IL-6, or ICAM-1 protein expression. Moreover, animal study revealed that IM-pretreatment inhibited the A. actinomycetemcomitans-induced increase of ICAM-1 in gingival junctional epithelium. Taken together, these results suggested that IM can regulate inflammatory responses in HGEC by inhibiting the ERK or p38 MAP kinase signaling cascade, which may result in suppression of inflammation in gingival tissue, thereby contributing to the prevention of periodontitis.
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Affiliation(s)
- Tsuyoshi Miyagawa
- Department of Periodontal Medicine, Division of Applied Life Science, Hiroshima University Graduate School of Biomedical and Health Sciences, Japan
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Stevens RH, Moura Martins Lobo dos Santos CD, Zuanazzi D, Accioly Mattos MBD, Ferreira DF, Kachlany SC, Tinoco EM. Prophage induction in lysogenic Aggregatibacter actinomycetemcomitans cells co-cultured with human gingival fibroblasts, and its effect on leukotoxin release. Microb Pathog 2013; 54:54-9. [DOI: 10.1016/j.micpath.2012.09.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 09/12/2012] [Accepted: 09/13/2012] [Indexed: 10/27/2022]
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Abstract
Periodontitis is a highly prevalent, biofilm-mediated chronic inflammatory disease that results in the loss of the tooth-supporting tissues. It features two major clinical entities: chronic periodontitis, which is more common, and aggressive periodontitis, which usually has an early onset and a rapid progression. Natural killer (NK) cells are a distinct subgroup of lymphocytes that play a major role in the ability of the innate immune system to steer immune responses. NK cells are abundant in periodontitis lesions, and NK cell activation has been causally linked to periodontal tissue destruction. However, the exact mechanisms of their activation and their role in the pathophysiology of periodontitis are elusive. Here, we show that the predominant NK cell-activating molecule in periodontitis is CD2-like receptor activating cytotoxic cells (CRACC). We show that CRACC induction was significantly more pronounced in aggressive than chronic periodontitis and correlated positively with periodontal disease severity, subgingival levels of specific periodontal pathogens, and NK cell activation in vivo. We delineate how Aggregatibacter actinomycetemcomitans, an oral pathogen that is causally associated with aggressive periodontitis, indirectly induces CRACC on NK cells via activation of dendritic cells and subsequent interleukin 12 (IL-12) signaling. In contrast, we demonstrate that fimbriae from Porphyromonas gingivalis, a principal pathogen in chronic periodontitis, actively attenuate CRACC induction on NK cells. Our data suggest an involvement of CRACC-mediated NK cell activation in periodontal tissue destruction and point to a plausible distinction in the pathobiology of aggressive and chronic periodontitis that may help explain the accelerated tissue destruction in aggressive periodontitis.
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Zijnge V, Kieselbach T, Oscarsson J. Proteomics of protein secretion by Aggregatibacter actinomycetemcomitans. PLoS One 2012; 7:e41662. [PMID: 22848560 PMCID: PMC3405016 DOI: 10.1371/journal.pone.0041662] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 06/25/2012] [Indexed: 01/18/2023] Open
Abstract
The extracellular proteome (secretome) of periodontitis-associated bacteria may constitute a major link between periodontitis and systemic diseases. To obtain an overview of the virulence potential of Aggregatibacter actinomycetemcomitans, an oral and systemic human pathogen implicated in aggressive periodontitis, we used a combined LC-MS/MS and bioinformatics approach to characterize the secretome and protein secretion pathways of the rough-colony serotype a strain D7S. LC-MS/MS revealed 179 proteins secreted during biofilm growth. Further to confirming the release of established virulence factors (e.g. cytolethal distending toxin [CDT], and leukotoxin [LtxA]), we identified additional putative virulence determinants in the secretome. These included DegQ, fHbp, LppC, Macrophage infectivity protein (MIP), NlpB, Pcp, PotD, TolB, and TolC. This finding indicates that the number of extracellular virulence-related proteins is much larger than previously demonstrated, which was also supported by in silico analysis of the strain D7S genome. Moreover, our LC-MS/MS and in silico data revealed that at least Type I, II, and V secretion are actively used to excrete proteins directly into the extracellular space, or via two-step pathways involving the Sec/Tat systems for transport across the inner membrane, and outer membrane factors, secretins and auto-transporters, respectively for delivery across the outer membrane. Taken together, our results provide a molecular basis for further elucidating the role of A. actinomycetemcomitans in periodontal and systemic diseases.
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Affiliation(s)
- Vincent Zijnge
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
| | | | - Jan Oscarsson
- Oral Microbiology, Department of Odontology, Umeå University, Umeå, Sweden
- * E-mail:
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Detert J, Pischon N, Burmester GR, Buttgereit F. [Pathogenesis of parodontitis in rheumatic diseases]. Z Rheumatol 2010; 69:109-12, 114-6. [PMID: 20107818 DOI: 10.1007/s00393-009-0560-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Inflammatory periodontal disease (PD) is a common disease worldwide that has a primarily bacterial aetiology and is characterized by dysregulation of the host inflammatory response. The degree of inflammation varies among individuals with PD independently of the degree of bacterial infection, suggesting that alteration of the immune function may substantially contribute to its extent. Factors such as smoking, education, and body mass index (BMI) are discussed as potential risk factors for PD. Most PD patients respond to bacterial invaders by mobilizing their defensive cells and releasing cytokines such as interleukin (IL)-1beta, tumour necrosis factor (TNF)-alpha, and IL-6, which ultimately causes tissue destruction by stimulating the production of collagenolytic enzymes, such matrix metalloproteinases. Recently, there has been growing evidence suggesting an association between PD and the increased risk of systemic diseases, such ateriosclerosis, diabetes mellitus, stroke, and rheumatoid arthritis (RA). PD and rheumatologic diseases such as RA share many pathological aspects and immunological findings.
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Affiliation(s)
- J Detert
- Klinik mit Schwerpunkt Rheumatologie und klinische Immunologie, Charité-Universitätsmedizin Berlin, Berlin, Deutschland.
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Maeda T, Maeda H, Yamabe K, Mineshiba J, Tanimoto I, Yamamoto T, Naruishi K, Kokeguchi S, Takashiba S. Highly expressed genes in a rough-colony-forming phenotype ofAggregatibacter actinomycetemcomitans: implication of amip-like gene for the invasion of host tissue. ACTA ACUST UNITED AC 2010; 58:226-36. [DOI: 10.1111/j.1574-695x.2009.00624.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Fujita T, Kishimoto A, Shiba H, Hayashida K, Kajiya M, Uchida Y, Matsuda S, Takeda K, Ouhara K, Kawaguchi H, Abiko Y, Kurihara H. Irsogladine maleate regulates neutrophil migration and E-cadherin expression in gingival epithelium stimulated by Aggregatibacter actinomycetemcomitans. Biochem Pharmacol 2010; 79:1496-505. [PMID: 20096665 DOI: 10.1016/j.bcp.2010.01.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 01/12/2010] [Accepted: 01/14/2010] [Indexed: 02/05/2023]
Abstract
Irsogladine maleate (IM) counters Aggregatibacter actinomycetemcomitans-induced reduction of the gap junction intercellular communication and the expression of zonula occludens-1, which is a major tight junction structured protein, in cultured human gingival epithelial cells (HGEC). In addition, IM obviates the A. actinomycetemcomitans-induced increase in interleukin (IL)-8 levels in HGEC. Thus, by regulating the intercellular junctional complex and chemokine secretion in HGEC, IM may be useful to prevent periodontal disease. To clarify the effects and regulatory mechanism of IM in vivo and in vitro, we examined the expression of E-cadherin and neutrophil chemotaxis induced by A. actinomycetemcomitans under IM pretreatment. Immunohistochemical studies revealed that A. actinomycetemcomitans application to the gingival sulcus decreased the number of cells positive for E-cadherin and increased those positive for cytokine-induced neutrophil chemoattractant-2alpha (CINC-2alpha) in rat gingival epithelium. However, in IM-pretreated rats, A. actinomycetemcomitans application had little effect on CINC-2alpha and E-cadherin in gingival epithelium. In cultured HGEC, real-time PCR and Western blotting showed that IM and the ERK inhibitor PD98059 abolished the A. actinomycetemcomitans-induced increase in CXCL-1 and IL-8 in HGEC. On the other hand, IM, PD98059, and the p38 MAP kinase inhibitor SB203580 recovered the decrease in E-cadherin expression. In addition, conditioned medium from A. actinomycetemcomitans-stimulated HGEC enhanced human neutrophil chemotaxis, compared to that from un-stimulated HGEC or that from A. actinomycetemcomitans-stimulated HGEC under IM pretreatment. Furthermore, IM down-regulated the p38 MAP kinase and ERK phosphorylations induced by A. actinomycetemcomitans. In conclusion, IM may control A. actinomycetemcomitans-induced gingival inflammation by regulating neutrophil migration and E-cadherin expression in gingival epithelium.
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Affiliation(s)
- Tsuyoshi Fujita
- Department of Periodontal Medicine, Hiroshima University Graduate School of Biomedical Sciences, Minami-ku, Japan.
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Huang CB, Emerson KA, Gonzalez OA, Ebersole JL. Oral bacteria induce a differential activation of human immunodeficiency virus-1 promoter in T cells, macrophages and dendritic cells. ACTA ACUST UNITED AC 2009; 24:401-7. [PMID: 19702954 DOI: 10.1111/j.1399-302x.2009.00533.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
INTRODUCTION The human immunodeficiency virus (HIV) can integrate into T cells, macrophages and dendritic cells resulting in a latent infection. Reports have also demonstrated that various microbial and host cell factors can trigger HIV reactivation leading to HIV recrudescence, potentially undermining highly active antiretroviral therapies. METHODS This study evaluated the capacity of oral bacteria associated with chronic periodontal infections to stimulate HIV promoter activation in various cell models of HIV latency. RESULTS T cells (1G5) challenged with oral bacteria demonstrated a dose-response of HIV promoter activation with a subset of the bacteria, as well as kinetics that were generally similar irrespective of the stimuli. Direct bacterial challenge of the T cells resulted in increased activation of approximately 1.5- to 7-fold over controls. Challenge of macrophages (BF24) indicated different kinetics for individual bacteria and resulted in consistent increases in promoter activation of five fold to six fold over basal levels for all bacteria except Streptococcus mutans. Dendritic cells showed increases in HIV reactivation of 7- to 34-fold specific for individual species of bacteria. CONCLUSION These results suggested that oral bacteria have the capability to reactivate HIV from latently infected cells, showing a relationship of mature dendritic cells > immature dendritic cells > macrophages > or = T cells. Expression of various pattern recognition receptors on these various cell types may provide insight into the primary receptors/signaling pathways used for reactivation by the bacteria.
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Affiliation(s)
- C B Huang
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY 40536, USA.
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Kimizuka R, Kato T, Hashimoto S, Yamanaka-Okada A, Okuda K, Ishihara K. Congo Red-binding Protein in Rough-phenotype Aggregatibacter actinomycetemcomitans is Amyloid-like Fiber. THE BULLETIN OF TOKYO DENTAL COLLEGE 2009; 50:23-9. [DOI: 10.2209/tdcpublication.50.23] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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24
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Wang PL, Azuma Y, Shinohara M, Ohura K. Effect ofActinobacillus actinomycetemcomitansprotease on the proliferation of gingival epithelial cells. Oral Dis 2008. [DOI: 10.1034/j.1601-0825.2001.70406.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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25
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Ouhara K, Komatsuzawa H, Shiba H, Uchida Y, Kawai T, Sayama K, Hashimoto K, Taubman MA, Kurihara H, Sugai M. Actinobacillus actinomycetemcomitans outer membrane protein 100 triggers innate immunity and production of beta-defensin and the 18-kilodalton cationic antimicrobial protein through the fibronectin-integrin pathway in human gingival epithelial cells. Infect Immun 2006; 74:5211-20. [PMID: 16926414 PMCID: PMC1594852 DOI: 10.1128/iai.00056-06] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Antimicrobial peptides, human beta-defensin (hBD), and the 18-kDa cationic antimicrobial protein (CAP18) are components of innate immunity. These peptides have antimicrobial activity against bacteria, fungi, and viruses. Actinobacillus actinomycetemcomitans is a gram-negative facultative anaerobe implicated in the initiation of periodontitis. The innate immunity peptides have antibacterial activity against A. actinomycetemcomitans. We investigated the molecular mechanism of human gingival epithelial cells (HGEC) responding to exposure to A. actinomycetemcomitans. HGEC constitutively express hBD1 and inducibly express hBD2, hBD3, and CAP18 on exposure to A. actinomycetemcomitans. The level of expression varies among clinical isolates. In the signaling pathway for hBD2 induction by the bacterial contact, we demonstrate that the mitogen-activated protein (MAP) kinase and not the NF-kappaB transcription factor pathway is used. We found the outer membrane protein 100 (Omp100; identified by molecular mass) is the component inducing the hBD2 response. Omp100 binds to fibronectin, an extracellular matrix inducing hBD2 via the MAP kinase pathway. Anti-integrin alpha(5)beta(1), antifibronectin, genistein, and PP2 suppress the Omp100-induced expression of hBD2, suggesting that Src kinase is involved through integrin alpha(5)beta(1). The inflammatory cytokines, tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6 and IL-8, produced by HGEC on contact with A. actinomycetemcomitans also stimulate expression of hBD2. Further, neutralizing antibody against TNF-alpha or IL-8 partially inhibits the induction of hBD2 on bacterial contact. Therefore, we found that the induction of the antimicrobial peptides is mediated by a direct response principally through an Omp100-fibronectin interaction, and using secondary stimulation by inflammatory cytokines induced by the bacterial exposure.
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Affiliation(s)
- Kazuhisa Ouhara
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical Sciences, Kasumi 1-2-3, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan
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Abstract
In recent years, the frequency of serious cardiovascular infections such as endocarditis has increased, particularly in association with nosocomially acquired antibiotic-resistant pathogens. Growing evidence suggests a crucial role for the interaction of bacteria with human platelets in the pathogenesis of cardiovascular infections. Here, we review the nature of the interactions between platelets and bacteria, and the role of these interactions in the pathogenesis of endocarditis and other cardiovascular diseases.
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Affiliation(s)
- J Ross Fitzgerald
- Centre for Infectious Diseases, The Chancellor's Building, New Royal Infirmary, University of Edinburgh, Edinburgh EH16 4SB, Scotland, UK
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Ihalin R, Karched M, Eneslätt K, Asikainen S. Characterization of immunoaffinity purified peptidoglycan-associated lipoprotein of Actinobacillus actinomycetemcomitans. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 831:116-25. [PMID: 16378764 DOI: 10.1016/j.jchromb.2005.11.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2005] [Revised: 11/25/2005] [Accepted: 11/29/2005] [Indexed: 11/28/2022]
Abstract
Peptidoglycan-associated lipoprotein (PAL) is a highly conserved structural outer membrane protein among Gram-negative bacteria. In some species, it is proinflammatory and released extracellularly. We purified a newly identified PAL (AaPAL) of a periodontal pathogen Actinobacillus actinomycetemcomitans by using AaPAL antipeptide antibodies coupled to immunoaffinity chromatography column. No protein impurities originating in A. actinomycetemcomitans were found in the final product. Sera from patients infected by A. actinomycetemcomitans recognized the purified AaPAL. The present purification method seems to be suitable for isolation of AaPAL and probably PALs of other bacterial species, and applicable in studies investigating proinflammatory mechanisms of A. actinomycetemcomitans.
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Affiliation(s)
- Riikka Ihalin
- Division of Oral Microbiology, Umeå University, Umeå SE-90185, Sweden
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Iwata T, Mitani A, Ishihara Y, Tanaka S, Yamamoto G, Kikuchi T, Naganawa T, Matsumura Y, Suga T, Koide M, Sobue T, Suzuki T, Noguchi T. Actinobacillus actinomycetemcomitans Y4 capsular polysaccharide induces IL-1beta mRNA expression through the JNK pathway in differentiated THP-1 cells. Clin Exp Immunol 2005; 141:261-9. [PMID: 15996190 PMCID: PMC1809438 DOI: 10.1111/j.1365-2249.2005.02836.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2005] [Indexed: 11/26/2022] Open
Abstract
Capsular polysaccharide from Actinobacillus actinomycetemcomitans Y4 (Y4 CP) induces bone resorption in a mouse organ culture system and osteoclast formation in mouse bone marrow cultures, as reported in previous studies. We also found that Y4 CP inhibits the release of interleukin (IL)-6 and IL-8 from human gingival fibroblast (HGF). Thus Y4 CP induces various responses in localized tissue and leads to the secretion of several cytokines. However, the effects of Y4 CP on human monocytes/macrophages are still unclear. In this study, THP-1 cells, which are a human monocytic cell line, were stimulated with Y4 CP, and we measured gene expression in inflammatory cytokine and signal transduction pathways. IL-1beta and tumour necrosis factor (TNF)-alpha mRNA were induced from Y4 CP-treated THP-1 cells. IL-1beta mRNA expression was increased according to the dose of Y4 CP, and in a time-dependent manner. IL-1beta mRNA expression induced by Y4 CP (100 microg/ml) was approximately 7- to 10-fold greater than that in the control by real-time PCR analysis. Furthermore, neither PD98059, a specific inhibitor of extracellular signal-regulated kinase nor SB203580, a specific inhibitor of p38 kinase prevented the IL-1beta expression induced by Y4 CP. However, JNK Inhibitor II, a specific inhibitor of c-Jun N-terminal kinase (JNK) prevented the IL-1beta mRNA expression induced by Y4 CP in a concentration-dependent manner. These results indicate that Y4 CP-mediated JNK pathways play an important role in the regulation of IL-1beta mRNA. Therefore, Y4 CP-transduced signals for IL-1beta induction in the antibacterial action of macrophages may provide a therapeutic strategy for periodontitis.
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Affiliation(s)
- T Iwata
- Department of Periodontology, School of Dentistry, Aichi-Gakuin University, Nagoya 464-8651, Japan
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Ushiba Y, Ohta H. Ecophysiology of the Oral Opportunistic Pathogen Actinobacillus actinomycetemcomitans with Special Emphasis on Leukotoxin Production. Microbes Environ 2004. [DOI: 10.1264/jsme2.19.190] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Yuuji Ushiba
- Department of Bioresource Science, Ibaraki University College of Agriculture
| | - Hiroyuki Ohta
- Department of Bioresource Science, Ibaraki University College of Agriculture
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30
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Asakawa R, Komatsuzawa H, Kawai T, Yamada S, Goncalves RB, Izumi S, Fujiwara T, Nakano Y, Suzuki N, Uchida Y, Ouhara K, Shiba H, Taubman MA, Kurihara H, Sugai M. Outer membrane protein 100, a versatile virulence factor of Actinobacillus actinomycetemcomitans. Mol Microbiol 2003; 50:1125-39. [PMID: 14622404 DOI: 10.1046/j.1365-2958.2003.03748.x] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Actinobacillus actinomycetemcomitans (Aa) is one of the pathogenic bacteria involved in periodontal diseases. We have previously identified six major outer membrane proteins (Omps) of Aa Y4. Among them is an Omp with high molecular mass, designated Omp100, which has homology to a variety of virulence factors. Electron microscopic observation indicated that Omp100 is randomly localized on the cell surface of Aa. Aa Y4 has been shown to adhere and invade KB or normal human gingival keratinocytes. Anti-Omp100 antibody inhibited 50% of adhesion and 70% of invasion of Aa Y4 to KB cells. An Omp100 knock-out mutant had a decreased adhesion and invasion efficiency of 60%, compared with that of the wild type. Escherichia coli HB101 expressing Omp100 adhered twofold and invaded 10-fold more than the wild-type E. coli HB101. HB101 expressing Omp100 showed resistance to serum by trapping factor H, an inhibitor for C3b, with Omp100. Omp100 induced inflammatory cytokine responses of interleukin (IL)-8, IL-6 and tumour necrosis factor (TNF)alpha in epithelial cells, and induced IL-1beta and TNFalpha production in mouse macrophages. These results indicate that Omp100 is a versatile virulence factor that may demonstrate potential significance in the onset of periodontal diseases related to Aa.
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Affiliation(s)
- Ryuji Asakawa
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical Sciences, Kasumi 1-2-3, Minami-ku, Hiroshima City, Hiroshima 734-8553, Japan
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Yamano R, Ohara M, Nishikubo S, Fujiwara T, Kawamoto T, Ueno Y, Komatsuzawa H, Okuda K, Kurihara H, Suginaka H, Oswald E, Tanne K, Sugai M. Prevalence of cytolethal distending toxin production in periodontopathogenic bacteria. J Clin Microbiol 2003; 41:1391-8. [PMID: 12682119 PMCID: PMC153874 DOI: 10.1128/jcm.41.4.1391-1398.2003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cytolethal distending toxin (CDT) is a newly identified virulence factor produced by several pathogenic bacteria implicated in chronic infection. Seventy three strains of periodontopathogenic bacteria were examined for the production of CDT by a HeLa cell bioassay and for the presence of the cdt gene by PCR with degenerative oligonucleotide primers, which were designed based on various regions of the Escherichia coli and Campylobacter cdtB genes, which have been successfully used for the identification and cloning of cdtABC genes from Actinobacillus actinomycetemcomitans Y4 (M. Sugai et al., Infect. Immun. 66:5008-5019, 1998). CDT activity was found in culture supernatants of 40 of 45 tested A. actinomycetemcomintans strains, but the titer of the toxin varied considerably among these strains. PCR experiments indicated the presence of Y4-type cdt sequences in these strains, but the rest of A. actinomycetemcomitans were negative by PCR amplification and also by Southern blot analysis for the cdtABC gene. In the 40 CDT-positive strains, Southern hybridization with HindIII-digested genomic DNA revealed that there are at least 6 restriction fragment length polymorphism types. This suggests that the cdtABC flanking region is highly polymorphic, which may partly explain the variability of the CDT activity in the culture supernatants. The rest of tested strains of periodontopathogenic bacteria did not have detectable CDT production by the HeLa cell assay and for cdtB sequences by PCR analysis under our experimental conditions. These results strongly suggested that CDT is a unique toxin predominantly produced by A. actinomycetemcomitans among periodontopathogenic bacteria.
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Affiliation(s)
- Ryousuke Yamano
- Department of Bacteriology, Hiroshima University Graduate School of Biomedical Sciences, Minami-ku, Hiroshima 734-8553, Japan
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Hirosue M, Kokeguchi S, Maeda H, Nishimura F, Takashiba S, Murayama Y. Characterization of two genes encoding ferritin-like protein in Actinobacillus actinomycetemcomitans. Microbiol Immunol 2002; 45:721-7. [PMID: 11762755 DOI: 10.1111/j.1348-0421.2001.tb01307.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Two genes encoding ferritin-like protein, designated afnA and afnB, were identified in the upstream region of actX on the Actinobacillus actinomycetemcomitans chromosomal DNA. The actX has been reported to be a regulatory gene homologous to the Escherichia coli fnr, which controls the growth and virulence of A. actinomycetemcomitans under anaerobic conditions. The afnB located 340 bp-upstream from the actX, and the afnA located just 15 bp-upstream from afnB. The afnA and afnB encoded 161 and 165 amino acid residues, respectively, which were similar to ferritin-like proteins of other microorganisms. Western immunoblotting using rabbit antiserum against E. coli ferritin showed these two proteins, which are reactive with the serum with 19-kDa molecular masses, are produced from A. actinomycetemcomitans. The N-terminal amino acid sequences of the two proteins were consequent with those deduced from afnA and afnB. Northern hybridization revealed that the afnA and afnB constituted a bicistronic operon and the accumulation of afnA and afnB mRNA was upregulated under aerobic conditions. These findings suggested that the operon was regulated by the presence of oxygen. The two ferritin-like proteins may have important roles in the adaptation of A. actinomycetemcomitans to oxidative environmental changes.
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Affiliation(s)
- M Hirosue
- Department of Patho-physiology, Division of Periodontal Science, Okayama University Graduate School of Medicine and Dentistry, Japan
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Komatsuzawa H, Asakawa R, Kawai T, Ochiai K, Fujiwara T, Taubman MA, Ohara M, Kurihara H, Sugai M. Identification of six major outer membrane proteins from Actinobacillus actinomycetemcomitans. Gene 2002; 288:195-201. [PMID: 12034509 DOI: 10.1016/s0378-1119(02)00500-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have identified six major sarcosyl-insoluble outer membrane proteins (Omp) of Actinobacillus actinomycetemcomitans Y4, and designated them as Omp100, Omp64, Omp39, Omp29, Omp18 and Omp16 according to the molecular mass. A similar N-terminal sequence was found in the first 15 amino acid residues of Omp16 and Omp18. The N-terminal sequence of Omp29 matched perfectly with the sequence previously identified. We cloned and determined the DNA sequences of three complete genes encoding Omp100, Omp64 and Omp18/16, and one incomplete gene encoding Omp39. Each Omp revealed homologies with some bacterial virulence factors responsible for adhesion, invasion, serum resistance, or protein antigenicity. Serum from patients with periodontitis suspected to be related to A. actinomycetemcomintans infection strongly reacted with Omp100, Omp29 and Omp16 as did serum from mice immunized with A. actinomycetemcomitans Y4 whole bacteria. These findings suggest that Omps of A. actinomycetemcomitans can be associated with periodontal disease.
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Affiliation(s)
- Hitoshi Komatsuzawa
- Department of Microbiology, Hiroshima University Faculty of Dentistry, Kasumi 1-2-3, Minami-ku, Hiroshima City, Japan.
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Kaplan JB, Perry MB, MacLean LL, Furgang D, Wilson ME, Fine DH. Structural and genetic analyses of O polysaccharide from Actinobacillus actinomycetemcomitans serotype f. Infect Immun 2001; 69:5375-84. [PMID: 11500407 PMCID: PMC98647 DOI: 10.1128/iai.69.9.5375-5384.2001] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The oral bacterium Actinobacillus actinomycetemcomitans is implicated as a causative agent of localized juvenile periodontitis (LJP). A. actinomycetemcomitans is classified into five serotypes (a to e) corresponding to five structurally and antigenically distinct O polysaccharide (O-PS) components of their respective lipopolysaccharide molecules. Serotype b has been reported to be the dominant serotype isolated from LJP patients. We determined the lipopolysaccharide O-PS structure from A. actinomycetemcomitans CU1000, a strain isolated from a 13-year-old African-American female with LJP which had previously been classified as serotype b. The O-PS of strain CU1000 consisted of a trisaccharide repeating unit composed of L-rhamnose and 2-acetamido-2-deoxy-D-galactose (molar ratio, 2:1) with the structure -->2)-alpha-L-Rhap-(1-3)-2-O-(beta-D-GalpNAc)-alpha-L-Rhap-(1-->* O-PS from strain CU1000 was structurally and antigenically distinct from the O-PS molecules of the five known A. actinomycetemcomitans serotypes. Strain CU1000 was mutagenized with transposon IS903phikan, and three mutants that were deficient in O-PS synthesis were isolated. All three transposon insertions mapped to a single 1-kb region on the chromosome. The DNA sequence of a 13.1-kb region surrounding these transposon insertions contained a cluster of 14 open reading frames that was homologous to gene clusters responsible for the synthesis of A. actinomycetemcomitans serotype b, c, and e O-PS antigens. The CU1000 gene cluster contained two genes that were not present in serotype-specific O-PS antigen clusters of the other five known A. actinomycetemcomitans serotypes. These data indicate that strain CU1000 should be assigned to a new A. actinomycetemcomitans serotype, designated serotype f. A PCR assay using serotype-specific PCR primers showed that 3 out of 20 LJP patients surveyed (15%) harbored A. actinomycetemcomitans strains carrying the serotype f gene cluster. The finding of an A. actinomycetemcomitans serotype showing serological cross-reactivity with anti-serotype b-specific antiserum suggests that a reevaluation of strains previously classified as serotype b may be warranted.
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Affiliation(s)
- J B Kaplan
- Department of Oral Pathology, Biology and Diagnostic Sciences, New Jersey Dental School, Newark, New Jersey 07103-2714, USA.
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35
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Zadeh HH, Nalbant A, Park K. Large-scale early in vitro response to actinobacillus actinomycetemcomitans suggests superantigenic activation of T-cells. J Dent Res 2001; 80:356-62. [PMID: 11269729 DOI: 10.1177/00220345010800011101] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The mode of T-cell response to Actinobacillus actinomycetemcomitans is largely unknown. The present study sought to investigate the hypothesis that A. actinomycetemcomitans expresses superantigens, capable of antigen-non-specific T-cell activation. To that end, peripheral blood mononuclear cells were stimulated with A. actinomycetemcomitans, and T-cell expression of the early activation marker, CD69, was determined by flow cytometry. Results showed that A. actinomycetemcomitans activated a large number of T-cells with magnitude similar to that of staphylococcal enterotoxin superantigens. A. actinomycetemcomitans sonicate preferentially activated T-cells expressing Vbeta5.1 and Vbeta8, while the extracellular preparation activated Vbeta5.1+, Vbeta8+, and Vbeta12+ T-cells. T-cell response to A. actinomycetemcomitans was observed in the presence of autologous, as well as heterologous, antigen-presenting cells, suggesting a MHC-non-restricted response. Thus, the in vitro response to A. actinomycetemcomitans is characterized by large-scale T-cell activation in a Vbeta-specific and MHC-non-restricted manner, consistent with the involvement of superantigens.
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MESH Headings
- Aggregatibacter actinomycetemcomitans/immunology
- Antibodies, Monoclonal
- Antigen-Presenting Cells/immunology
- Antigens, Bacterial/immunology
- Antigens, CD/immunology
- Antigens, Differentiation, T-Lymphocyte/immunology
- CD3 Complex/immunology
- Flow Cytometry
- Fluorescent Antibody Technique, Direct
- Humans
- Lectins, C-Type
- Lymphocyte Activation/immunology
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Superantigens/immunology
- T-Lymphocyte Subsets/immunology
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Affiliation(s)
- H H Zadeh
- Department of Periodontology, University of Southern California, School of Dentistry, Los Angeles 90098, USA.
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36
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Paju S, Goulhen F, Asikainen S, Grenier D, Mayrand D, Uitto V. Localization of heat shock proteins in clinical Actinobacillus actinomycetemcomitans strains and their effects on epithelial cell proliferation. FEMS Microbiol Lett 2000; 182:231-5. [PMID: 10620671 DOI: 10.1111/j.1574-6968.2000.tb08900.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Actinobacillus actinomycetemcomitans is an important pathogen in periodontitis. In the present study we localized the GroEL- and DnaK-like heat shock proteins (Hsp) in subcellular fractions of 12 A. actinomycetemcomitans strains of various clinical origin and compared their effects on periodontal epithelial cell proliferation and viability. In all strains, GroEL-like protein was found in the membrane, cytoplasm, and periplasm, whereas DnaK-like protein was present in the cytoplasm and periplasm. No correlation was observed between the Hsp expression and the serotype or origin of A. actinomycetemcomitans strains. The bacterial membrane fractions that expressed the GroEL-like protein moderately or strongly induced epithelial cell proliferation more strongly than strains that expressed the protein weakly. The results suggest that GroEL-like Hsp may play a role in the virulence of A. actinomycetemcomitans by increasing epithelial proliferation.
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Affiliation(s)
- S Paju
- Institute of Dentistry, University of Helsinki, P.O. Box 41, FIN-00014, Helsinki, Finland.
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Fives-Taylor PM, Meyer DH, Mintz KP, Brissette C. Virulence factors of Actinobacillus actinomycetemcomitans. Periodontol 2000 1999; 20:136-67. [PMID: 10522226 DOI: 10.1111/j.1600-0757.1999.tb00161.x] [Citation(s) in RCA: 214] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A. actinomycetemcomitans has clearly adapted well to its environs; its armamentarium of virulence factors (Table 2) ensures its survival in the oral cavity and enables it to promote disease. Factors that promote A. actinomycetemcomitans colonization and persistence in the oral cavity include adhesins, bacteriocins, invasins and antibiotic resistance. It can interact with and adhere to all components of the oral cavity (the tooth surface, other oral bacteria, epithelial cells or the extracellular matrix). The adherence is mediated by a number of distinct adhesins that are elements of the cell surface (outer membrane proteins, vesicles, fimbriae or amorphous material). A. actinomycetemcomitans enhances its chance of colonization by producing actinobacillin, an antibiotic that is active against both streptococci and Actinomyces, primary colonizers of the tooth surface. The fact that A. actinomycetemcomitans resistance to tetracyclines, a drug often used in the treatment of periodontal disease, is on the rise is an added weapon. Periodontal pathogens or their pathogenic products must be able to pass through the epithelial cell barrier in order to reach and cause destruction to underlying tissues (the gingiva, cementum, periodontal ligament and alveolar bone). A. actinomycetemcomitans is able to elicit its own uptake into epithelial cells and its spread to adjacent cells by usurping normal epithelial cell function. A. actinomycetemcomitans may utilize these remarkable mechanisms for host cell infection and migration to deeper tissues. A. actinomycetemcomitans also orchestrates its own survival by elaborating factors that interfere with the host's defense system (such as factors that kill phagocytes and impair lymphocyte activity, inhibit phagocytosis and phagocyte chemotaxis or interfere with antibody production). Once the organisms are firmly established in the gingiva, the host responds to the bacterial onslaught, especially to the bacterial lipopolysaccharide, by a marked and continual inflammatory response, which results in the destruction of the periodontal tissues. A. actinomycetemcomitans has at least three individual factors that cause bone resorption (lipopolysaccharide, proteolysis-sensitive factor and GroEL), as well as a number of activities (collagenase, fibroblast cytotoxin, etc.) that elicit detrimental effects on connective tissue and the extracellular matrix. It is of considerable interest to know that A. actinomycetemcomitans possesses so many virulence factors but unfortunate that only a few have been extensively studied. If we hope to understand and eradicate this pathogen, it is critical that in-depth investigations into the biochemistry, genetic expression, regulation and mechanisms of action of these factors be initiated.
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Affiliation(s)
- P M Fives-Taylor
- Department of Microbiology & Molecular Genetics, University of Vermont, Burlington, USA
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Olsen I, Shah HN, Gharbia SE. Taxonomy and biochemical characteristics of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. Periodontol 2000 1999; 20:14-52. [PMID: 10522221 DOI: 10.1111/j.1600-0757.1999.tb00156.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- I Olsen
- Department of Oral Biology, Dental Faculty, University of Oslo, Norway
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39
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Yamamoto S, Mogi M, Kinpara K, Ishihara Y, Ueda N, Amano K, Nishihara T, Noguchi T, Togari A. Anti-proliferative capsular-like polysaccharide antigen from Actinobacillus actinomycetemcomitans induces apoptotic cell death in mouse osteoblastic MC3T3-E1 cells. J Dent Res 1999; 78:1230-7. [PMID: 10371246 DOI: 10.1177/00220345990780060601] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) has been implicated in the etiology of localized juvenile periodontitis (LJP), and produces a multiplicity of tissue-damaging products. Among those products, the capsular-like polysaccharide antigen (CPA) from A. actinomycetemcomitans is a potent mediator of bone resorption. In fact, this CPA (serotype b) is known to promote osteoclast-like cell formation via interleukin (IL)-1alpha production in mouse marrow cultures. Although osteoblasts complete bone formation, there are few reports focusing on the effect of CPA in bone-forming activity of osteoblasts in inflammatory disease sites. We hypothesized that CPA plays a mediating role in osteoblastic cells. Therefore, the purpose of this study was to examine the effect of CPA from A. actinomycetemcomitans on the mouse osteoblastic cell line MC3T3-E1 and human osteosarcoma SaOS-2 cells. A. actinomycetemcomitans serotype c resulted in a potent dose-dependent inhibition of cell proliferation of both cell lines. Characterization of the antiproliferative activity in the CPA demonstrated that it was not cytotoxic for MC3T3-E1. A 20-hour incubation with CPA-c resulted in a significant increase in apoptotic cell death in the cells, as evaluated by both cellular DNA fragmentation ELISA and FACS analysis. In contrast to the results obtained with a cytokine mixture (tumor necrosis factor-alpha, IL-1beta, and interferon-gamma), no inducible nitric oxide (NO) synthase gene expression or NO release could be detected in MC3T3-E1 after incubation with CPA-c. Further, both CPA-b and -c caused potent induction of apoptosis-related modifiers, e.g., Fas mRNA, whereas bcl-2 mRNA levels were unchanged. Therefore, this study has shown that CPA from A. actinomycetemcomitans contains a potent antiproliferative polysaccharide whose activity is associated with apoptotic cell death in MC3T3-E1, and that CPA per se is an inducer of apoptosis mediated by the Fas system but not by NO.
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Affiliation(s)
- S Yamamoto
- Department of Periodontology, School of Dentistry, Aichi-Gakuin University, Nagoya, Japan
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40
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Schytte Blix IJ, Helgeland K, Hvattum E, Lyberg T. Lipopolysaccharide from Actinobacillus actinomycetemcomitans stimulates production of interleukin-1beta, tumor necrosis factor-alpha, interleukin-6 and interleukin-1 receptor antagonist in human whole blood. J Periodontal Res 1999; 34:34-40. [PMID: 10086884 DOI: 10.1111/j.1600-0765.1999.tb02219.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) is supposed to be an important etiological agent in localized juvenile periodontitis (LJP). We have studied the effect of lipopolysaccharide (LPS) extracted from these periodontopathogenic bacteria on synthesis of the proinflammatory cytokines, interleukin-1beta(IL-1beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and the anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) in human whole blood. LPS from A. actinomycetemcomitans in concentrations > or =1 ng/ml induced a significant production of all these proinflammatory cytokines, whereas LPS from Escherichia coli (E. coli), strain 026:B6 had to be added in concentrations > or =1 microg/ml to obtain a similar effect. Similarly, LPS from A. actinomycetemcomitans > or =0.1 ng/ml resulted in production of IL-1ra, while LPS from E. coli 026:B6 had to be added at > or =10 ng/ml to obtain similar effects. It has been suggested that the ratio between production of proinflammatory and anti-inflammatory cytokines may influence the outcome of periodontal diseases. Other in vitro and in vivo studies have, however, indicated that very large excesses (100-1000 times) of IL-1ra compared to IL-1beta are required to shift the IL-1ra:IL-1beta ratio in favor of an inhibition of IL-1 bioactivity. In our ex vivo system, we found that stimulation with extremely low doses of A. actinomycetemcomitans LPS (0.1-1 ng/ml) resulted in IL-1ra production solely, without concomitant production of IL-1beta, the excess of IL-1ra over IL-1beta peaking at 1 ng/ml, which accordingly should suggest that LPS from A. actinomycetemcomitans primarily has proinflammatory effects.
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Affiliation(s)
- I J Schytte Blix
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Norway.
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41
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Sugai M, Kawamoto T, Pérès SY, Ueno Y, Komatsuzawa H, Fujiwara T, Kurihara H, Suginaka H, Oswald E. The cell cycle-specific growth-inhibitory factor produced by Actinobacillus actinomycetemcomitans is a cytolethal distending toxin. Infect Immun 1998; 66:5008-19. [PMID: 9746611 PMCID: PMC108622 DOI: 10.1128/iai.66.10.5008-5019.1998] [Citation(s) in RCA: 177] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Actinobacillus actinomycetemcomitans has been shown to produce a soluble cytotoxic factor(s) distinct from leukotoxin. We have identified in A. actinomycetemcomitans Y4 a cluster of genes encoding a cytolethal distending toxin (CDT). This new member of the CDT family is similar to the CDT produced by Haemophilus ducreyi. The CDT from A. actinomycetemcomitans was produced in Escherichia coli and was able to induce cell distension, growth arrest in G2/M phase, nucleus swelling, and chromatin fragmentation in HeLa cells. The three proteins, CDTA, -B and -C, encoded by the cdt locus were all required for toxin activity. Antiserum raised against recombinant CDTC completely inhibited the cytotoxic activity of culture supernatant and cell homogenate fractions of A. actinomycetemcomitans Y4. These results strongly suggest that the CDT is responsible for the cytotoxic activity present in the culture supernatant and cell homogenate fractions of A. actinomycetemcomitans Y4. This CDT is a new putative virulence factor of A. actinomycetemcomitans and may play a role in the pathogenesis of periodontal diseases.
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Affiliation(s)
- M Sugai
- Department of Microbiology, Hiroshima University School of Dentistry, Hiroshima 734-8553, Japan. /
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42
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Gu K, Bainbridge B, Darveau RP, Page RC. Antigenic components of Actinobacillus actinomycetemcomitans lipopolysaccharide recognized by sera from patients with localized juvenile periodontitis. ORAL MICROBIOLOGY AND IMMUNOLOGY 1998; 13:150-7. [PMID: 10093529 DOI: 10.1111/j.1399-302x.1998.tb00726.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The dominant antigen of Actinobacillus actinomycetemcomitans recognized by high-titer sera from patients with localized juvenile periodontitis is the serotype antigen located in the O-side chains of lipopolysaccharide. Whether such sera contain antibodies reactive with other epitopes in lipopolysaccharide, as is the case for patients with rapidly progressive periodontitis, remains unknown. We prepared and characterized by gas liquid chromatography lipopolysaccharide, lipid A, core carbohydrate with no or few O-side chains (core) and high-molecular-mass carbohydrate-rich in O-side chains (oligosaccharide) from A. actinomyce-temcomitans ATCC 43718 (serotype b, Y4). Using enzyme-linked immunosorbent assay (ELISA), sera from 36 patients with localized juvenile periodontitis were surveyed using whole-cell sonicate as plate antigen. The seven highest titer sera were selected for further study. Specific IgG antibody binding was observed to intact lipopolysaccharide and to all the lipopolysaccharide fractions. The mean titers were highest for intact lipopolysaccharide (138.8 ELISA units), and lipid A (122 ELISA units), followed by the core fraction (81 ELISA units) and the oligosaccharide fraction (69.5 ELISA units). ELISA inhibition revealed that the core fraction at a concentration of 10 micrograms/test well inhibited antibody binding to A. actinomycetemcomitans lipopolysaccharide by a mean value of 56.7%. To further characterize antibody binding to the core fraction, ELISA inhibition was performed using as inhibitor the core carbohydrate fraction of the Re mutant of Salmonella minnesota, which is known to contain only alpha-keto-3-deoxyoctonate residues and phosphate. This fraction at 10 micrograms/test well inhibited binding of antibodies from 6 of 7 test sera with a mean value of 49.2%. Thus, sera from patients with localized juvenile periodontitis contain antibodies that bind to the O-side chains of lipopolysaccharide, as has been previously reported, but they also contain antibodies that bind to lipid A and to lipopolysaccharide core polysaccharide epitopes, specifically to alpha-keto-3-deoxyoctonate moieties. The humoral immune response to A. actinomycetemcomitans in patients with localized juvenile periodontitis is more complex than previously reported and is very similar to that of patients with rapidly progressive periodontitis.
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Affiliation(s)
- K Gu
- Department of Periodontics, University of Washington, Seattle 98195, USA
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Meyer DH, Mintz KP, Fives-Taylor PM. Models of invasion of enteric and periodontal pathogens into epithelial cells: a comparative analysis. CRITICAL REVIEWS IN ORAL BIOLOGY AND MEDICINE : AN OFFICIAL PUBLICATION OF THE AMERICAN ASSOCIATION OF ORAL BIOLOGISTS 1997; 8:389-409. [PMID: 9391752 DOI: 10.1177/10454411970080040301] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Bacterial invasion of epithelial cells is associated with the initiation of infection by many bacteria. To carry out this action, bacteria have developed remarkable processes and mechanisms that co-opt host cell function and stimulate their own uptake and adaptation to the environment of the host cell. Two general types of invasion processes have been observed. In one type, the pathogens (e.g., Salmonella and Yersinia spp.) remain in the vacuole in which they are internalized and replicate within the vacuole. In the other type, the organism (e.g., Actinobacillus actinomycetemcomitans, Shigella flexneri, and Listeria monocytogenes) is able to escape from the vacuole, replicate in the host cell cytoplasm, and spread to adjacent host cells. The much-studied enteropathogenic bacteria usurp primarily host cell microfilaments for entry. Those organisms which can escape from the vacuole do so by means of hemolytic factors and C type phospholipases. The cell-to-cell spread of these organisms is mediated by microfilaments. The investigation of invasion by periodontopathogens is in its infancy in comparison with that of the enteric pathogens. However, studies to date on two invasive periodontopathogens. A actinomycetemcomitans and Porphyromonas (Bacteroides) gingivalis, reveal that these bacteria have developed invasion strategies and mechanisms similar to those of the enteropathogens. Entry of A. actinomycetemcomitans is mediated by microfilaments, whereas entry of P. gingivalis is mediated by both microfilaments and microtubules. A. actinomycetemcomitans, like Shigella and Listeria, can escape from the vacuole and spread to adjacent cells. However, the spread of A. actinomycetemcomitans is linked to host cell microtubules, not microfilaments. The paradigms presented establish that bacteria which cause chronic infections, such as periodontitis, and bacteria which cause acute diseases, such as dysentery, have developed similar invasion strategies.
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Affiliation(s)
- D H Meyer
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington 05405, USA
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44
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Ou JG, Bainbridge B, Gu K, Sims TJ, Whitney CW, Darveau RP, Chen HA, Houston LS, Page RC. Recognition of antigenic epitopes in lipopolysaccharide and protein from Actinobacillus actinomycetemcomitans by serum antibodies in untreated rapidly progressive periodontitis patients. ORAL MICROBIOLOGY AND IMMUNOLOGY 1997; 12:11-9. [PMID: 9151639 DOI: 10.1111/j.1399-302x.1997.tb00361.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Actinobacillus actinomycetemcomitans has been associated with early-onset periodontitis, including the localized juvenile and rapidly progressive forms. The immunodominant antigens of A. actinomycetemcomitans recognized by rapidly progressive periodontitis patients remain unidentified. Sera from 22 patients with rapidly progressive periodontitis and 20 periodontally normal subjects were tested by enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G antibodies to whole-cell sonicate, protein, purified lipopolysaccharide and lipopolysaccharide fractions of A. actinomycetemcomitans. The median titers of rapidly progressive periodontitis patients and control subjects to whole-cell sonicate were 25.0 and 14.5 ELISA units, respectively (not significantly different). Binding of antibody from patient sera occurred to both the lipopolysaccharide and the protein fractions, with greater binding to lipopolysaccharide than to protein. We show for the first time that patient sera contain antibodies that bind specifically to antigenic epitopes in lipid A and in the core carbohydrate of lipopolysaccharide that were previously considered to be inaccessible and unavailable, as well as to epitopes in the O side chains. Sera manifesting antibody titers 2-fold or greater than the median titer for control sera were judged to be seropositive. More patients were seropositive for lipid A than for any of the other antigen preparations studied, and the median titer for patient sera to lipid A but to none of the other purified lipopolysaccharide fractions was significantly elevated relative to control values. Of 22 patients, 10 were seropositive to whole-cell sonicate, 7 to protein, 8 to lipopolysaccharide, 7 to the high-molecular-weight lipopolysaccharide-polysaccharide fraction rich in O side chains, and 16 to lipid A. The core carbohydrate did not adhere to the test plate surface, and this precluded ELISA measurements. However, when the core carbohydrate was used in the ELISA inhibition assay, it reduced antibody binding to lipopolysaccharide-coated plates by up to 45%, thereby demonstrating antibody binding to core carbohydrate. The core carbohydrate fraction from the Re mutant of Salmonella minnesota known to contain no O-side chains also inhibited binding of specific antibody to plates coated with A actinomycetemcomitans lipopolysaccharide. Overall, there was extreme variation in responses among patients to the various antigen preparations, with no single pattern dominating. Lipopolysaccharide and its components appear to be the immunodominant epitopes, since most rapidly progressive periodontitis patients are seropositive for lipopolysaccharide and/or its components and they have titers relative to those for proteins.
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Affiliation(s)
- J G Ou
- Department of Periodontics, School of Dentistry, University of Washington, Seattle, USA
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Valcarcel J, Allardet-Servent A, Bourg G, O'Callaghan D, Michailesco P, Ramuz M. Investigation of the Actinobacillus actinomycetemcomitans genome by pulsed field gel electrophoresis. ORAL MICROBIOLOGY AND IMMUNOLOGY 1997; 12:33-9. [PMID: 9151642 DOI: 10.1111/j.1399-302x.1997.tb00364.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Pulsed field gel electrophoresis was used to investigate nineteen strains of Actinobacillus actinomycetemcomitans. The genome was found to contain a single chromosome whose size we estimate to be 2300 kb from the sum of restriction fragments generated with rare cutting endonucleases. We detected the presence of large plasmids with sizes ranging from 35 to 300 kb. In some strains, extrachromosomal elements constitute over 20% of the total genome. Comparison of the profiles of ApaI digests of the 19 strains showed a high degree of polymorphism with 13 different profiles, providing a new tool for epidemiological studies.
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Affiliation(s)
- J Valcarcel
- Institut National de la Santé et de la Recherche Médicale, Unité 431, Faculté de Médecine, Nimes, France
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46
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Abstract
Twenty out of 33 Actinobacillus actinomycetemcomitans strains formed hemolytic colonies on horse blood agar plates under anaerobic conditions. The hemolytic activity found in A. actinomycetemcomitans strain 137HE was examined. This activity was detected in the late exponential to early stationary phases of growth. Human erythrocytes were the most susceptible, followed by rabbit, sheep, horse and swine red blood cells. The majority of activity was detected in the cell-associated vesicle fraction. Zwitterionic detergent 3-[(3-cholamidopropyl)-dimethyl-ammonio]-1-propanesulfonate (CHAPS) extract from whole cells was semipurified by ammonium sulfate precipitation, preparative isoelectric focusing (IEF) and gel-filtration chromatography to yield a major band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) with a molecular mass of 12 kDa. Heating at 80 C for 30 min and treatment with proteinase K or trypsin resulted in complete disappearance of the hemolytic activity. Sulphydryl reagents enhanced activity and small amounts of cholesterol inhibited it. In summary, we demonstrated the presence of hemolysin in A. actinomycetemcomitans, and examined and characterized it.
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Affiliation(s)
- R Kimizuka
- Department of Microbiology, Tokyo Dental College, Chiba, Japan
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Kato T, Kimizuka R, Okuda K. Isolation and characterization of hemolytic genes from Actinobacillus actinomycetemcomitans. FEMS Microbiol Lett 1996; 143:217-21. [PMID: 8837475 DOI: 10.1111/j.1574-6968.1996.tb08483.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Periodontopathic Actinobacillus actinomyceremcomitans produces hemolysin and other leukotoxins. In the present study, two distinct clones which lysed horse erythrocytes were isolated by screening genomic DNA libraries of A. actinomycetemcomitans ATCC 43718 on blood agar plates. DNA hybridization analysis indicates that there were two distinct hemolytic genes present. Sonicated extracts from both Escherichia coli clones possessed hemolytic activities on horse, sheep and human erythrocytes, but not those of rabbit. Rabbit antiserum to A. actinomycetemcomitans ATCC 43718 whole cells inhibited the hemolytic activities of these clones.
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Affiliation(s)
- T Kato
- Department of Microbiology, Tokyo Dental College, Chiba, Japan
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McArthur WP, Stroup S, McClellan S, Leung KP. Differentiation of the serotype b and species-specific antigens of Actinobacillus actinobacillus actinomycetemcomitans recognized by monoclonal antibodies. ORAL MICROBIOLOGY AND IMMUNOLOGY 1996; 11:209-19. [PMID: 9002872 DOI: 10.1111/j.1399-302x.1996.tb00172.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The serotype b antigens have been reported to be associated with lipopolysaccharide. Using murine monoclonal antibodies specific for either a serotype b antigen or the Actinobacillus actinomycetemcomitans species, the relationship of the two epitopes to lipopolysaccharide was determined. Both the species-specific and serotype b-specific monoclonal antibodies bound to whole cells, vesicles and conventionally isolated lipopolysaccharide and polysaccharide material derived from A. actinomycetemcomitans culture supernatants. Serotype b-specific monoclonal antibodies bound to the polysaccharide of acid-hydrolyzed lipopolysaccharide. Species-specific monoclonal antibodies bound to both the polysaccharide and the lipid A fraction of lipopolysaccharide after acid hydrolysis. Polymyxin b partially inhibited the binding of the species-specific monoclonal antibodies to lipopolysaccharide and had no effect on the binding of the serotype b-specific monoclonal antibodies to lipopolysaccharide. Lipopolysaccharide from whole bacteria and polysaccharide material isolated from culture supernatants were separated by gel filtration chromatography in deoxycholate into fractions that contained serotype b antigen, both serotype b and species-specific antigens, or species-specific antigen. SDS-polyacrylamide gel electrophoresis and Western blotting analysis of the fractions revealed that the serotype b antigen was on a high-molecular-weight polysaccharide material. The species-specific antigen was on a ladder of lower-molecular-weight polysaccharides identical to the blot pattern of lipopolysaccharide molecules separated by polyacrylamide gel electrophoresis and stained with silver stain. Chemical analysis of the polysaccharide containing serotype b antigen revealed 85% ribose, 11% glucose, and no lipid. Chemical content of the species-specific antigenic material revealed a composition typical of lipopolysaccharide. Immunoelectron microscopy using the species- or serotype b-specific monoclonal antibodies confirmed the biochemical and immunological characterization of the two antigens, showing that the species-specific epitopes were on the surface of the A. actinomycetemcomitans cell membrane and the serotype b-specific epitopes on the amorphous material extending from the cell surface. The data indicated that the serotype b antigen, detected by the antibody, was separable from lipopolysaccharide and was an A. actinomycetemcomitans capsular material. The species-specific antigen, being more conserved than the serotype antigen, was on all the lipopolysaccharide molecular species.
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Affiliation(s)
- W P McArthur
- Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, USA
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Chen PB, Davern LB, Katz J, Eldridge JH, Michalek SM. Host responses induced by co-infection with Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in a murine model. ORAL MICROBIOLOGY AND IMMUNOLOGY 1996; 11:274-81. [PMID: 9002881 DOI: 10.1111/j.1399-302x.1996.tb00181.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In this study, evidence is presented that mixed infection with the periodontal pathogens Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans results in a synergistic effect in their pathogenicity and in their ability to induce humoral and cellular host responses. BALB/c mice were injected subcutaneously on the back with P. gingivalis ATCC 53977, A. actinomycetemocomitans 75 or a mixture of both bacteria. Samples of blood and fluid from abscesses formed at the site of injection (first degree) or distant from the injection site were collected for microbiologic analysis. Serum and spleens were obtained for evaluation of humoral and cellular responses to P. gingivalis and A actinomycetemocomitans. Mice injected with A. actinomycetemcomitans had first-degree lesions only, whereas mice injected with P. gingivalis and A. actinomycetemcomitans had lesions at first- and second-degree sites from which both bacterial species were isolated. A serum anti-P. gingivalis response was induced in P. gingivalis-injected mice, which was higher in mice injected with P. gingivalis and A. actinomycetemcomitans. This pattern was not seen in the anti-A, actinomycetemcomitans response. Lymphoproliferative responses to phytohemagglutinin, Escherichia coli lipopolysaccharide and P. gingivalis of spleen cells from infected mice were decreased, especially following co-infection. Furthermore, co-infection of mice resulted in the greatest decrease in the number of CD5+, especially CD4+ lymphocytes.
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Affiliation(s)
- P B Chen
- Department of Oral Biology, School of Dental Medicine, State University of New York at Buffalo, USA
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Perry MB, MacLean LL, Gmür R, Wilson ME. Characterization of the O-polysaccharide structure of lipopolysaccharide from Actinobacillus actinomycetemcomitans serotype b. Infect Immun 1996; 64:1215-9. [PMID: 8606081 PMCID: PMC173906 DOI: 10.1128/iai.64.4.1215-1219.1996] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We previously reported that the serotype b antigen of Actinobacillus actinomycetemcomitans is a constituent of the polysaccharide region of lipopolysaccharide (LPS) and contains significant amount of the neutral sugars rhamnose and fucose (M. Wilson and R. Schifferle, Infect. Immun. 59:1544-1551, 1991). In the present study, we determined the structure of the O antigen of A. actinomycetemcomitans Y4 (serotype b) LPS. Aqueous phase LPS was obtained from a phenol-water extract of A. actinomycetemcomitans Y4. This material was found to react with rabbit polyclonal antiserum to serotype b but not with antisera specific for other A. actinomycetemcomitans serotypes. Analyses revealed that the O polysaccharide of Y4 LPS consists of a polymer of trisaccharide repeating units composed of D-Fuc, AL-Rha, and D-GalNAc residues. An identical structure was obtained for the O polysaccharide of LPS from A. actinomycetemcomitans JP2, another serotype b strain. These results indicate that the serotype b antigen of A. actinomycetemcomitans is defined by a trisaccharide repeating unit present in the O polysaccharide of LPS.
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Affiliation(s)
- M B Perry
- Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada
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