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Razooqi Z, Tjellström I, Höglund Åberg C, Kwamin F, Claesson R, Haubek D, Johansson A, Oscarsson J. Association of Filifactor alocis and its RTX toxin gene ftxA with periodontal attachment loss, and in synergy with Aggregatibacter actinomycetemcomitans. Front Cell Infect Microbiol 2024; 14:1376358. [PMID: 38596650 PMCID: PMC11002136 DOI: 10.3389/fcimb.2024.1376358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 03/18/2024] [Indexed: 04/11/2024] Open
Abstract
The Gram-positive bacterium, Filifactor alocis is an oral pathogen, and approximately 50% of known strains encode a recently identified repeat-in-toxin (RTX) protein, FtxA. By assessing a longitudinal Ghanaian study population of adolescents (10-19 years of age; mean age 13.2 years), we recently discovered a possible correlation between deep periodontal pockets measured at the two-year follow-up, presence of the ftxA gene, and a high quantity of F. alocis. To further understand the contribution of F. alocis and FtxA in periodontal disease, we used qPCR in the present study to assess the carriage loads of F. alocis and the prevalence of its ftxA gene in subgingival plaque specimens, sampled at baseline from the Ghanaian cohort (n=500). Comparing these results with the recorded clinical attachment loss (CAL) longitudinal progression data from the two-year follow up, we concluded that carriers of ftxA-positive F. alocis typically exhibited higher loads of the bacterium. Moreover, high carriage loads of F. alocis and concomitant presence of the ftxA gene were two factors that were both associated with an enhanced prevalence of CAL progression. Interestingly, CAL progression appeared to be further promoted upon the simultaneous presence of F. alocis and the non-JP2 genotype of Aggregatibacter actinomycetemcomitans. Taken together, our present findings are consistent with the notion that F. alocis and its ftxA gene promotes CAL during periodontal disease.
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Affiliation(s)
| | | | | | - Francis Kwamin
- Dental School University of Ghana, Korle-Bu, Accra, Ghana
| | - Rolf Claesson
- Department of Odontology, Umeå University, Umeå, Sweden
| | - Dorte Haubek
- Jammerbugt Municipal Dental Service, Brovst, Denmark
| | | | - Jan Oscarsson
- Department of Odontology, Umeå University, Umeå, Sweden
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Mishra A, Dou Y, Wang C, Fletcher HM. Filifactor alocis enhances survival of Porphyromonas gingivalis W83 in response to H 2 O 2 -induced stress. Mol Oral Microbiol 2024; 39:12-26. [PMID: 38041478 PMCID: PMC10842171 DOI: 10.1111/omi.12445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/16/2023] [Accepted: 11/17/2023] [Indexed: 12/03/2023]
Abstract
A dysbiotic microbial community whose members have specific/synergistic functions that are modulated by environmental conditions, can disturb homeostasis in the subgingival space leading to destructive inflammation, plays a role in the progression of periodontitis. Filifactor alocis, a gram-positive, anaerobic bacterium, is a newly recognized microbe that shows a strong correlation with periodontal disease. Our previous observations suggested F. alocis to be more resistant to oxidative stress compared to Porphyromonas gingivalis. The objective of this study is to further determine if F. alocis, because of its increased resistance to oxidative stress, can affect the survival of other 'established' periodontal pathogens under environmental stress conditions typical of the periodontal pocket. Here, we have shown that via their interaction, F. alocis protects P. gingivalis W83 under H2 O2 -induced oxidative stress conditions. Transcriptional profiling of the interaction of F. alocis and P. gingivalis in the presence of H2 O2 -induced stress revealed the modulation of several genes, including those with ABC transporter and other cellular functions. The ABC transporter operon (PG0682-PG0685) of P. gingivalis was not significant to its enhanced survival when cocultured with F. alocis under H2 O2 -induced oxidative stress. In F. alocis, one of the most highly up-regulated operons (FA0894-FA0897) is predicted to encode a putative manganese ABC transporter, which in other bacteria can play an essential role in oxidative stress protection. Collectively, the results may indicate that F. alocis could likely stabilize the microbial community in the inflammatory microenvironment of the periodontal pocket by reducing the oxidative environment. This strategy could be vital to the survival of other pathogens, such as P. gingivalis, and its ability to adapt and persist in the periodontal pocket.
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Affiliation(s)
- Arunima Mishra
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Yuetan Dou
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Charles Wang
- Department of Basic Sciences, School of Medicine, Center for Genomics, Loma Linda University, Loma Linda, California, USA
| | - Hansel M Fletcher
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
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Kim SH, Kang IC. Induction of TNF-α by Filifactor alocis in THP-1 macrophagic cells. Arch Oral Biol 2023; 155:105806. [PMID: 37729700 DOI: 10.1016/j.archoralbio.2023.105806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/08/2023] [Accepted: 09/14/2023] [Indexed: 09/22/2023]
Abstract
OBJECTIVES Filifactor alocis is an emerging periodontal pathogen, and macrophage-produced tumor necrosis factor-α (TNF-α) plays important roles in periodontal pathogenesis. In this study, we investigated F. alocis-stimulated TNF-α production in THP-1 macrophagic cells. DESIGN Phorbol 12-myristate 13-acetate-differentiated THP-1 macrophagic cells were challenged with F. alocis ATCC 35896 for various durations. TNF-α mRNA expression and protein secretion were determined using RT-PCR and ELISA, respectively. Activation of protein kinases and transcription factor proteins was evaluated by Western blot analysis. RESULTS Live F. alocis stimulated THP-1 cells to produce TNF-α in a dose-dependent manner. However, glutaraldehyde-killed or heat-killed F. alocis showed no effectiveness for TNF-α induction. In contrast, both live and killed Porphyromonas gingivalis robustly increased TNF-α expression. Furthermore, F. alocis was unable to stimulate TNF-α expression in Toll-like receptor 2 (TLR2) knockout THP-1 cells. F. alocis activated all three mitogen-activated protein kinases: extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal kinase (JNK). Pharmacological inhibition of ERK and JNK, but not p38, significantly reduced F. alocis-induced TNF-α production. Finally, increased levels of phospho-c-Jun were detected in F. alocis-stimulated THP-1 cells. CONCLUSIONS These results suggest that F. alocis induces TNF-α production in THP-1 macrophagic cells primarily by activating the TLR2, JNK, and c-Jun pathways.
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Affiliation(s)
- So-Hee Kim
- Department of Oral Microbiology, School of Dentistry, Chonnam National University, Gwangju, the Republic of Korea
| | - In-Chol Kang
- Department of Oral Microbiology, School of Dentistry, Chonnam National University, Gwangju, the Republic of Korea.
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Romero-Martínez R, Maher A, Àlvarez G, Figueiredo R, León R, Arredondo A. Whole Genome Sequencing and Phenotypic Analysis of Antibiotic Resistance in Filifactor alocis Isolates. Antibiotics (Basel) 2023; 12:1059. [PMID: 37370380 DOI: 10.3390/antibiotics12061059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
There is scarce knowledge regarding the antimicrobial resistance profile of F. alocis. Therefore, the objective of this research was to assess antimicrobial resistance in recently obtained F. alocis clinical isolates and to identify the presence of antimicrobial resistance genes. Isolates were obtained from patients with periodontal or peri-implant diseases and confirmed by sequencing their 16S rRNA gene. Confirmed isolates had their genome sequenced by whole genome sequencing and their phenotypical resistance to nine antibiotics (amoxicillin clavulanate, amoxicillin, azithromycin, clindamycin, ciprofloxacin, doxycycline, minocycline, metronidazole, and tetracycline) tested by E-test strips. Antimicrobial resistance genes were detected in six of the eight isolates analyzed, of which five carried tet(32) and one erm(B). Overall, susceptibility to the nine antibiotics tested was high except for azithromycin in the isolate that carried erm(B). Moreover, susceptibility to tetracycline, doxycycline, and minocycline was lower in those isolates that carried tet(32). The genetic surroundings of the detected genes suggested their inclusion in mobile genetic elements that might be transferrable to other bacteria. These findings suggest that, despite showing high susceptibility to several antibiotics, F. alocis might obtain new antimicrobial resistance traits due to its acceptance of mobile genetic elements with antibiotic resistance genes in their genome.
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Affiliation(s)
| | - Anushiravan Maher
- Oral Surgery and Implantology, Faculty of Medicine and Health Sciences, University of Barcelona, 08036 Barcelona, Spain
| | - Gerard Àlvarez
- Department of Microbiology, DENTAID Research Center, 08290 Barcelona, Spain
| | - Rui Figueiredo
- Oral Surgery and Implantology, Faculty of Medicine and Health Sciences, University of Barcelona, 08036 Barcelona, Spain
| | - Rubén León
- Department of Microbiology, DENTAID Research Center, 08290 Barcelona, Spain
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Ji S, Kook JK, Park SN, Lim YK, Choi GH, Jung JS. Characteristics of the Salivary Microbiota in Periodontal Diseases and Potential Roles of Individual Bacterial Species To Predict the Severity of Periodontal Disease. Microbiol Spectr 2023; 11:e0432722. [PMID: 37191548 PMCID: PMC10269672 DOI: 10.1128/spectrum.04327-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 04/27/2023] [Indexed: 05/17/2023] Open
Abstract
The purposes of this study were to examine the compositional changes in the salivary microbiota according to the severity of periodontal disease and to verify whether the distribution of specific bacterial species in saliva can distinguish the severity of disease. Saliva samples were collected from 8 periodontally healthy controls, 16 patients with gingivitis, 19 patients with moderate periodontitis, and 29 patients with severe periodontitis. The V3 and V4 regions of the 16S rRNA gene in the samples were sequenced, and the levels of 9 bacterial species showing significant differences among the groups by sequencing analysis were identified using quantitative real-time PCR (qPCR). The predictive performance of each bacterial species in distinguishing the severity of disease was evaluated using a receiver operating characteristic curve. Twenty-nine species, including Porphyromonas gingivalis, increased as the severity of disease increased, whereas 6 species, including Rothia denticola, decreased. The relative abundances of P. gingivalis, Tannerella forsythia, Filifactor alocis, and Prevotella intermedia determined by qPCR were significantly different among the groups. The three bacterial species P. gingivalis, T. forsythia, and F. alocis were positively correlated with the sum of the full-mouth probing depth and were moderately accurate at distinguishing the severity of periodontal disease. In conclusion, the salivary microbiota showed gradual compositional changes according to the severity of periodontitis, and the levels of P. gingivalis, T. forsythia, and F. alocis in mouth rinse saliva had the ability to distinguish the severity of periodontal disease. IMPORTANCE Periodontal disease is one of the most widespread medical conditions and the leading cause of tooth loss, imposing high economic costs and an increasing burden worldwide as life expectancy increases. Changes in the subgingival bacterial community during the progression of periodontal disease can affect the entire oral ecosystem, and bacteria in saliva can reflect the degree of bacterial imbalance in the oral cavity. This study explored whether the specific bacterial species in saliva can distinguish the severity of periodontal disease by analyzing the salivary microbiota and suggested P. gingivalis, T. forsythia, and F. alocis as biomarkers for distinguishing the severity of periodontal disease in saliva.
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Affiliation(s)
- Suk Ji
- Department of Periodontology, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Republic of Korea
| | - Joong-Ki Kook
- Korean Collection for Oral Microbiology, Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju, Republic of Korea
| | - Soon-Nang Park
- Korean Collection for Oral Microbiology, Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju, Republic of Korea
| | - Yun Kyong Lim
- Korean Collection for Oral Microbiology, Department of Oral Biochemistry, School of Dentistry, Chosun University, Gwangju, Republic of Korea
| | - Geum Hee Choi
- Department of Periodontology, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Republic of Korea
| | - Jae-Suk Jung
- Department of Periodontology, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Republic of Korea
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Mangar M, Mishra A, Yang Z, Deivanayagam C, Fletcher HM. Characterization of FA1654: A putative DPS protein in Filifactor alocis. Mol Oral Microbiol 2023; 38:23-33. [PMID: 36412172 PMCID: PMC9905271 DOI: 10.1111/omi.12398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/13/2022] [Accepted: 10/26/2022] [Indexed: 11/24/2022]
Abstract
The survival/adaptation of Filifactor alocis, a fastidious Gram-positive asaccharolytic anaerobe, to the inflammatory environment of the periodontal pocket requires an ability to overcome oxidative stress. Moreover, its pathogenic characteristics are highlighted by its capacity to survive in the oxidative-stress microenvironment of the periodontal pocket and a likely ability to modulate the microbial community dynamics. There is still a significant gap in our understanding of its mechanism of oxidative stress resistance and its impact on the virulence and pathogenicity of the microbial biofilm. Coinfection of epithelial cells with F. alocis and Porphyromonas gingivalis resulted in the upregulation of several genes, including HMPREF0389_01654 (FA1654). Bioinformatics analysis indicates that FA1654 has a "di-iron binding domain" and could function as a DNA starvation and stationary phase protection (DPS) protein. We have further characterized the FA1654 protein to determine its role in oxidative stress resistance in F. alocis. In the presence of hydrogen peroxide-induced oxidative stress, there was an ∼1.3 fold upregulation of the FA1654 gene in F. alocis. Incubation of the purified FA1654 protein with DNA in the presence of hydrogen peroxide and iron resulted in the protection of the DNA from Fenton-mediated degradation. Circular dichroism and differential scanning fluorimetry studies have documented the intrinsic ability of rFA1654 protein to bind iron; however, the rFA1654 protein is missing the intrinsic ability to reduce hydrogen peroxide. Collectively, the data may suggest that FA1654 in F. alocis is involved in oxidative stress resistance via an ability to protect against Fenton-mediated oxidative stress-induced damage.
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Affiliation(s)
- Malissa Mangar
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Arunima Mishra
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Zhengrong Yang
- Department of Biochemistry and Molecular Genetics, University of Alabama, Birmingham, AL USA
| | - Champion Deivanayagam
- Department of Biochemistry and Molecular Genetics, University of Alabama, Birmingham, AL USA
| | - Hansel M. Fletcher
- Division of Microbiology & Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA,Corresponding author: Phone: (909) 558-8497, FAX: (909) 558-4035,
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Iskander MMZ, Lamont GJ, Tan J, Pisano M, Uriarte SM, Scott DA. Tobacco smoke exacerbates Filifactor alocis pathogenicity. J Clin Periodontol 2023; 50:121-130. [PMID: 36122937 PMCID: PMC9976951 DOI: 10.1111/jcpe.13729] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 08/11/2022] [Accepted: 09/14/2022] [Indexed: 11/30/2022]
Abstract
AIM Filifactor alocis has recently emerged as a periodontal pathobiont that appears to thrive in the oral cavity of smokers. We hypothesized that identification of smoke-responsive F. alocis genes would provide insight into adaptive strategies and that cigarette smoke would enhance F. alocis pathogenesis in vivo. MATERIALS AND METHODS F. alocis was grown in vitro and cigarette smoke extract-responsive genes determined by RNAseq. Mice were exposed, or not, to mainstream 1R6F research cigarette smoke and infected with F. alocis, or not, in an acute ligature model of periodontitis. Key clinical, infectious, and immune data were collected. RESULTS In culture, F. alocis growth was unaffected by smoke conditioning and only a small number of genes were specifically regulated by smoke exposure. Reduced murine mass, differences in F. alocis-cognizant antibody production, and altered immune profiles as well as altered alveolar bone loss were all attributable to smoke exposure and/or F. alocis infection in vivo. CONCLUSIONS F. alocis is well-adapted to tobacco-rich conditions and its pathogenesis is enhanced by tobacco smoke exposure. A smoke-exposed ligature model of periodontitis shows promise as a tool with which to further unravel mechanisms underlying tobacco-enhanced, bacteria-induced disease.
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Affiliation(s)
- Mina M Z Iskander
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Gwyneth J Lamont
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Jinlian Tan
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Michele Pisano
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - Silvia M Uriarte
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
| | - David A Scott
- Department of Oral Immunology and Infectious Diseases, University of Louisville School of Dentistry, Louisville, Kentucky, USA
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Pandian DS, Victor DJ, Cholan P, Prakash PSG, Subramanian S, Shankar SP. Comparative analysis of the red-complex organisms and recently identified periodontal pathogens in the subgingival plaque of diabetic and nondiabetic patients with severe chronic periodontitis. J Indian Soc Periodontol 2023; 27:51-56. [PMID: 36873973 PMCID: PMC9979820 DOI: 10.4103/jisp.jisp_136_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/01/2021] [Accepted: 01/09/2022] [Indexed: 03/07/2023] Open
Abstract
Aim This analytical case-control study sought to evaluate the presence of the recently established putative periodontal pathogen organisms, Filifactor alocis and Fretibacterium fastidiosum, against the levels of the already established red-complex pathogens, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola, in chronic periodontitis sites of patients with and without diabetes mellitus. Materials and Methods Fifty-six subgingival plaque samples were obtained from the deepest sites of subjects diagnosed with severe chronic periodontitis with and without diabetes mellitus. These patients were categorized into two groups of 28 each. Clinical parameters were recorded and microbial analysis was done with quantitative polymerase chain reaction, and the bacterial counts of F. alocis and F. fastidiosum were determined and then compared with that of the red-complex organisms. Results The bacterial counts were found to be higher in the diabetic group than that in the nondiabetic group, which was statistically significant for T. forsythia (P < 0.037) and T. denticola (P < 0.003). The study found very less number of F. alocis, which was slightly higher in the diabetic group. When correlating the bacterial levels within the nondiabetic groups, the red complex species had a strong positive correlation both individually with F. alocis (P < 0.0001) and F. fastidiosum (P < 0.001) and also when the newer species was clubbed together as a cohort (P < 0.0001). Whereas, in the diabetic group, although there was a positive correlation, there was no statistical significance. Conclusion The results of this study highlighted the presence of a definite difference in the subgingival microbiota of both the patient groups evaluated. They also indicate that of the newly identified microorganisms, both the cohorts had higher levels of F. fastidiosum, suggesting a pathobiont-like role of this bacteria among both these periodontitis groups. F. alocis was comparatively lesser in number among the cohorts evaluated, and the cause for this decreased level of F. alocis needs to be further evaluated. The results of the present study depict a higher bacterial load in the diabetic group when compared to the nondiabetic group. Further, the study demonstrates a strong correlation between the red-complex species and the newer organisms in the nondiabetic group.
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Affiliation(s)
- Divya Shree Pandian
- Department of Periodontics, Karpaga Vinayaga Institute of Dental Sciences, Kanchipuram, Tamil Nadu, India
| | - Dhayanad John Victor
- Department of Periodontics, SRM Dental College and Hospital, Chennai, Tamil Nadu, India
| | - Priyanka Cholan
- Department of Periodontics, SRM Dental College and Hospital, Chennai, Tamil Nadu, India
| | - PSG Prakash
- Department of Periodontics, SRM Dental College and Hospital, Chennai, Tamil Nadu, India
| | - Sangeetha Subramanian
- Department of Periodontics, SRM Dental College and Hospital, Chennai, Tamil Nadu, India
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Razooqi Z, Höglund Åberg C, Kwamin F, Claesson R, Haubek D, Oscarsson J, Johansson A. Aggregatibacter actinomycetemcomitans and Filifactor alocis as Associated with Periodontal Attachment Loss in a Cohort of Ghanaian Adolescents. Microorganisms 2022; 10:microorganisms10122511. [PMID: 36557764 PMCID: PMC9781193 DOI: 10.3390/microorganisms10122511] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022] Open
Abstract
The aims of the present study were to document the presence of Aggregatibacter actinomyctemcomitans and the emerging oral pathogen Filifactor alocis, as well as to identify genotypes of these bacterial species with enhanced virulence. In addition, these data were analyzed in relation to periodontal pocket depth (PPD) and the progression of PPD from the sampled periodontal sites during a two-year period. Subgingival plaque samples were collected from 172 periodontal pockets of 68 Ghanaian adolescents. PPD at sampling varied from 3-14 mm and the progression from baseline, i.e., two years earlier up to 8 mm. The levels of A. actinomycetemcomitans and F. alocis were determined with quantitative PCR. The highly leukotoxic JP2-genotype of A. actinomycetemcomitans and the ftxA a gene of F. alocis, encoding a putative Repeats-in-Toxin (RTX) protein, were detected with conventional PCR. The prevalence of A. actinomycetemcomitans was 57%, and 14% of the samples contained the JP2 genotype. F. alocis was detected in 92% of the samples and the ftxA gene in 52%. The levels of these bacterial species were significantly associated with enhanced PPD and progression, with a more pronounced impact in sites positive for the JP2 genotype or the ftxA gene. Taken together, the results indicate that the presence of both A. actinomycetemcomitans and F. alocis with their RTX proteins are linked to increased PPD and progression of disease.
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Affiliation(s)
- Zeinab Razooqi
- Department of Odontology, Umeå University, 901 87 Umeå, Sweden
| | | | - Francis Kwamin
- Dental School University of Ghana, Korle-Bu, Accra KB 460, Ghana
| | - Rolf Claesson
- Department of Odontology, Umeå University, 901 87 Umeå, Sweden
| | - Dorte Haubek
- Jammerbugt Municipal Dental Service, Skolevej 1, DK-9460 Brovst, Denmark
| | - Jan Oscarsson
- Department of Odontology, Umeå University, 901 87 Umeå, Sweden
| | - Anders Johansson
- Department of Odontology, Umeå University, 901 87 Umeå, Sweden
- Correspondence: ; Tel.: +46-90-8856291
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Ozuna H, Snider I, Belibasakis GN, Oscarsson J, Johansson A, Uriarte SM. Aggregatibacter actinomycetemcomitans and Filifactor alocis: Two exotoxin-producing oral pathogens. Front Oral Health 2022; 3:981343. [PMID: 36046121 PMCID: PMC9420871 DOI: 10.3389/froh.2022.981343] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 07/27/2022] [Indexed: 12/22/2022] Open
Abstract
Periodontitis is a dysbiotic disease caused by the interplay between the microbial ecosystem present in the disease with the dysregulated host immune response. The disease-associated microbial community is formed by the presence of established oral pathogens like Aggregatibacter actinomycetemcomitans as well as by newly dominant species like Filifactor alocis. These two oral pathogens prevail and grow within the periodontal pocket which highlights their ability to evade the host immune response. This review focuses on the virulence factors and potential pathogenicity of both oral pathogens in periodontitis, accentuating the recent description of F. alocis virulence factors, including the presence of an exotoxin, and comparing them with the defined factors associated with A. actinomycetemcomitans. In the disease setting, possible synergistic and/or mutualistic interactions among both oral pathogens might contribute to disease progression.
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Affiliation(s)
- Hazel Ozuna
- Department of Microbiology and Immunology, School of Medicine, University of Louisville, Louisville, KY, United States
| | - Ian Snider
- Department of Biology, School of Arts and Sciences, University of Louisville, Louisville, KY, United States
| | | | - Jan Oscarsson
- Department of Odontology, Umeå University, Umeå, Sweden
| | | | - Silvia M. Uriarte
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, United States,*Correspondence: Silvia M. Uriarte
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Miralda I, Vashishta A, Rogers MN, Lamont RJ, Uriarte SM. The emerging oral pathogen, Filifactor alocis, extends the functional lifespan of human neutrophil. Mol Microbiol 2022; 117:1340-1351. [PMID: 35437843 PMCID: PMC9233153 DOI: 10.1111/mmi.14911] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 03/17/2022] [Accepted: 04/10/2022] [Indexed: 12/01/2022]
Abstract
Periodontitis is a chronic inflammatory infectious disease that affects the integrity of tooth‐supporting tissues and has adverse systemic consequences. Advances in sequencing technologies have uncovered organisms that are exclusively found in high numbers in periodontal lesions, such as the gram‐positive anaerobic rod, Filifactor alocis. F. alocis can manipulate neutrophil effector functions, which allows the organism to survive within these granulocytes. Several neutrophil functions have been tested in the context of F. alocis challenge, but the effect of the organism on neutrophil apoptosis is still unknown. RNA sequencing of human neutrophils challenged with F. alocis showed that apoptosis pathways were differentially regulated. Compared to media‐cultured controls, F. alocis‐challenged neutrophils maintain their nuclear morphology, do not stain for Annexin V or 7‐AAD, and have decreased DNA fragmentation. Inhibition of apoptosis by F. alocis involved reduced caspase‐3, −8, and − 9 activation and upregulation of important anti‐apoptotic proteins. Prolonged lifespan was dependent on contact through TLR2/6, and F. alocis‐challenged neutrophils retained their functional capacity to induce inflammation for longer timepoints. This is the first in‐depth characterization of neutrophil apoptotic programs in response to an oral pathogen and provides key information on how bacteria manipulate immune cell mechanisms to maintain a dysregulated inflammatory response.
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Affiliation(s)
- Irina Miralda
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA.,Present address: Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, WA, USA
| | - Aruna Vashishta
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
| | - Max N Rogers
- School of Medicine, University of Louisville, Louisville, KY, USA
| | - Richard J Lamont
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
| | - Silvia M Uriarte
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
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Aja E, Mishra A, Dou Y, Fletcher HM. Role of the Filifactor alocis Hypothetical Protein FA519 in Oxidative Stress Resistance. Microbiol Spectr 2021; 9:e0121221. [PMID: 34756068 PMCID: PMC8579941 DOI: 10.1128/spectrum.01212-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/14/2021] [Indexed: 11/30/2022] Open
Abstract
In the periodontal pocket, there is a direct correlation between environmental conditions, the dynamic oral microbial flora, and disease. The relative abundance of several newly recognized microbial species in the oral microenvironment has raised questions on their impact on disease development. One such organism, Filifactor alocis, is significant to the pathogenic biofilm structure. Moreover, its pathogenic characteristics are highlighted by its ability to survive in the oxidative-stress microenvironment of the periodontal pocket and alter the microbial community dynamics. There is a gap in our understanding of its mechanism(s) of oxidative stress resistance and impact on pathogenicity. Several proteins, including HMPRFF0389-00519 (FA519), were observed in high abundance in F. alocis during coinfection of epithelial cells with Porphyromonas gingivalis W83. Bioinformatics analysis shows that FA519 contains a "Cys-X-X-Cys zinc ribbon domain" which could be involved in DNA binding and oxidative stress resistance. We have characterized FA519 to elucidate its roles in the oxidative stress resistance and virulence of F. alocis. Compared to the wild-type strain, the F. alocis isogenic gene deletion mutant, FLL1013 (ΔFA519::ermF), showed significantly reduced sensitivity to hydrogen peroxide and nitric oxide-induced stress. The ability to form biofilm and adhere to and invade gingival epithelial cells was also reduced in the isogenic mutant. The recombinant FA519 protein was shown to protect DNA from Fenton-mediated damage with an intrinsic ability to reduce hydrogen peroxide and disulfide bonds. Collectively, these results suggest that FA519 is involved in oxidative stress resistance and can modulate important virulence attributes in F. alocis. IMPORTANCE Filifactor alocis is an emerging member of the periodontal community and is now proposed to be a diagnostic indicator of periodontal disease. However, due to the lack of genetic tools available to study this organism, not much is known about its virulence attributes. The mechanism(s) of oxidative stress resistance in F. alocis is unknown. Therefore, identifying the adaptive mechanisms utilized by F. alocis to survive in the oxidative stress environment of the periodontal pocket would lead to understanding its virulence regulation, which could help develop novel therapeutic treatments to combat the effects of periodontal disease. This study is focused on the characterization of FA519, a hypothetical protein in F. alocis, as a multifunctional protein that plays an important role in the reactive oxygen species-detoxification pathway. Collectively, our results suggest that FA519 is involved in oxidative stress resistance and can modulate important virulence attributes in F. alocis.
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Affiliation(s)
- Ezinne Aja
- Division of Microbiology and Molecular Genetics, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Arunima Mishra
- Division of Microbiology and Molecular Genetics, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Yuetan Dou
- Division of Microbiology and Molecular Genetics, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Hansel M. Fletcher
- Division of Microbiology and Molecular Genetics, Department of Basic Sciences, School of Medicine, Loma Linda University, Loma Linda, California, USA
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13
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Neelakandan A, Potluri R, Yadalam PK, Chakraborty P, Saravanan AV, Arunraj R. The Varied Proportion of Filifactor alocis in Periodontal Health and Disease in the South Indian Subpopulation. Contemp Clin Dent 2021; 12:433-438. [PMID: 35068845 PMCID: PMC8740782 DOI: 10.4103/ccd.ccd_803_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 09/29/2020] [Accepted: 10/31/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND AND AIM The periodontal microbiome being complex, this study was aimed to detect and quantify the prevalence of Filifactor alocis in various stages of periodontitis and to evaluate its prospect as a diagnostic marker for periodontal disease. SETTINGS AND DESIGN Sixty subjects were selected (20 healthy controls, 20 with chronic periodontitis, and 20 with aggressive periodontitis) for the study. MATERIALS AND METHODS Clinical parameters probing depth and the level of clinical attachment was recorded, subgingival plaque samples were collected. The F. alocis 16srDNA was cloned, sequenced, and used as the standard for real-time quantification of bacterial load using SYBR green chemistry. STATISTICAL ANALYSIS Clinical, microbiological, and quantitative polymerase chain reaction (PCR) data were analyzed using ANOVA and Pearson's coefficient correlation. RESULTS (a) Real-time PCR analysis showed the highest average F. alocis count in chronic periodontitis subjects (32,409.85), which was followed by count in healthy controls (3046.15) and the least count in aggressive periodontitis subjects (939.84). The bacterial count was statistically significant at P = 0.005. (b) An intra-group comparison reveals that there was a statistically significant increase in the bacterial count with age and mean probing pocket depth at P = 0.0005. CONCLUSION F. alocis population in aggressive periodontitis was lower compared to chronic periodontitis and healthy controls. The F. alocis population surge in healthy controls may be due to geographical variations and the ethnicity of the subjects. A higher population of F. alocis in chronic periodontitis proves its high pathogenic potential to invade the host tissues to aid in further periodontal destruction.
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Affiliation(s)
- Anila Neelakandan
- Department of Periodontology and Implantology, SRM Dental College, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Ravishankar Potluri
- Department of Periodontology and Implantology, SRM Dental College, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Pradeep Kumar Yadalam
- Department of Periodontology and Implantology, SRM Dental College, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Priyankar Chakraborty
- Department of Periodontology and Implantology, SRM Dental College, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - A. V. Saravanan
- Department of Periodontology and Implantology, SRM Dental College, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
| | - Rex Arunraj
- Department of Genetic Engineering, College of Engineering and Technology, SRM Institute of Science and Technology, Chennai, Tamil Nadu, India
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14
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Lamoureux C, Hascoet E, Tandé D, Le Bars H, Hannigsberg J, Héry-Arnaud G, Beauruelle C. Filifactor alocis bacteremia associated with facial cellulitis. Infect Dis Now 2021; 52:119-120. [PMID: 34464756 DOI: 10.1016/j.idnow.2021.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 08/24/2021] [Indexed: 10/20/2022]
Affiliation(s)
- C Lamoureux
- Département de bactériologie-virologie, hygiène hospitalière et parasitologie-mycologie, CHRU de Brest, 29238 Brest, France; Inserm, EFS, UMR 1078, GGB, Université de Brest, 29200 Brest, France.
| | - E Hascoet
- Département d'odontologie, CHRU de Brest, 29200 Brest, France
| | - D Tandé
- Département de bactériologie-virologie, hygiène hospitalière et parasitologie-mycologie, CHRU de Brest, 29238 Brest, France
| | - H Le Bars
- Département de bactériologie-virologie, hygiène hospitalière et parasitologie-mycologie, CHRU de Brest, 29238 Brest, France
| | - J Hannigsberg
- Service de gynécologie-obstétrique, CHRU de Brest, 29200 Brest, France
| | - G Héry-Arnaud
- Département de bactériologie-virologie, hygiène hospitalière et parasitologie-mycologie, CHRU de Brest, 29238 Brest, France; Inserm, EFS, UMR 1078, GGB, Université de Brest, 29200 Brest, France
| | - C Beauruelle
- Département de bactériologie-virologie, hygiène hospitalière et parasitologie-mycologie, CHRU de Brest, 29238 Brest, France; Inserm, EFS, UMR 1078, GGB, Université de Brest, 29200 Brest, France
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15
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Nogueira AVB, Nokhbehsaim M, Damanaki A, Eick S, Kirschneck C, Schröder A, Jantsch J, Deschner J. Filifactor alocis and Tumor Necrosis Factor-Alpha Stimulate Synthesis of Visfatin by Human Macrophages. Int J Mol Sci 2021; 22:1235. [PMID: 33513808 DOI: 10.3390/ijms22031235] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/18/2021] [Accepted: 01/24/2021] [Indexed: 12/18/2022] Open
Abstract
There is little known about the effect of the periodontopathogen Filifactor alocis on macrophages as key cells of the innate immune defense in the periodontium. Therefore, the aim of the present study was to investigate the effect of F. alocis and additionally of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNFα) on visfatin and other pro-inflammatory and proteolytic molecules associated with periodontitis in human macrophages. The presence of macrophage markers CD14, CD86, CD68, and CD163 was examined in gingival biopsies from healthy individuals and periodontitis patients. Human macrophages were incubated with F. alocis and TNFα for up to 2 d. The effects of both stimulants on macrophages were determined by real-time PCR, ELISA, immunocytochemistry, and immunofluorescence. F. alocis was able to significantly stimulate the synthesis of visfatin by human macrophages using TLR2 and MAPK pathways. In addition to visfatin, F. alocis was also able to increase the synthesis of cyclooxygenase 2, TNFα, and matrix metalloproteinase 1. Like F. alocis, TNFα was also able to stimulate the production of these proinflammatory and proteolytic molecules. Our results highlight the pathogenetic role of F. alocis in periodontal diseases and also underline the involvement of visfatin in the aetiopathogenesis of periodontitis.
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16
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Miralda I, Uriarte SM. Periodontal Pathogens' strategies disarm neutrophils to promote dysregulated inflammation. Mol Oral Microbiol 2020; 36:103-120. [PMID: 33128827 PMCID: PMC8048607 DOI: 10.1111/omi.12321] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/16/2020] [Accepted: 10/28/2020] [Indexed: 12/26/2022]
Abstract
Periodontitis is an irreversible, chronic inflammatory disease where inflammophilic pathogenic microbial communities accumulate in the gingival crevice. Neutrophils are a major component of the innate host response against bacterial challenge, and under homeostatic conditions, their microbicidal functions typically protect the host against periodontitis. However, a number of periodontal pathogens developed survival strategies to evade neutrophil microbicidal functions while promoting inflammation, which provides a source of nutrients for bacterial growth. Research on periodontal pathogens has largely focused on a few established species: Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, and Porphyromonas gingivalis. However, advances in culture-independent techniques have facilitated the identification of new bacterial species in periodontal lesions, such as the two Gram-positive anaerobes, Filifactor alocis and Peptoanaerobacter stomatis, whose characterization of pathogenic potential has not been fully described. Additionally, there is not a full understanding of the pathogenic mechanisms used against neutrophils by organisms that are abundant in periodontal lesions. This presents a substantial barrier to the development of new approaches to prevent or ameliorate the disease. In this review, we first summarize the neutrophil functions affected by the established periodontal pathogens listed above, denoting unknown areas that still merit a closer look. Then, we review the literature on neutrophil functions and the emerging periodontal pathogens, F. alocis and P. stomatis, comparing the effects of the emerging microbes to that of established pathogens, and speculate on the contribution of these putative pathogens to the progression of periodontal disease.
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Affiliation(s)
- Irina Miralda
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
| | - Silvia M Uriarte
- Department of Oral Immunology and Infectious Diseases, School of Dentistry, University of Louisville, Louisville, KY, USA
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17
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Zou RJ, Wu YF, Shen DN. [Network analysis and characteristics of keystone taxa in periodontitis]. Zhonghua Kou Qiang Yi Xue Za Zhi 2020; 55:1005-10. [PMID: 33280370 DOI: 10.3760/cma.j.cn112144-20200116-00018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Subgingival microorganisms can orchestrate the microbial community under the influence of environmental factors, thus causing the initiation and progression of periodontitis. Keystone taxa play an important role in the dynamic changes of microbial community. The co-occurrence network analysis may pave the way for screening periodontitis associated candidate keystone taxa in the periodontal microflora. These microorganisms, e.g. Porphyromonas gingivalis, might function via myriad of intermediary taxa or as the chokepoint community-remodeling drivers in response of environmental factors. Herein, we review and discuss the construction of microbial co-occurrence network, the way of screening and identifying keystone taxa using network analysis as well as the characteristic of candidate keystone taxa related to periodontitis for the purpose that keystone taxa and the role they played in dynamic succession of microflora could be well investigated.
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18
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Oscarsson J, Claesson R, Bao K, Brundin M, Belibasakis GN. Phylogenetic Analysis of Filifactor alocis Strains Isolated from Several Oral Infections Identified a Novel RTX Toxin, FtxA. Toxins (Basel) 2020; 12:toxins12110687. [PMID: 33143036 PMCID: PMC7692872 DOI: 10.3390/toxins12110687] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/20/2020] [Accepted: 10/28/2020] [Indexed: 12/16/2022] Open
Abstract
Filifactor alocis is a Gram-positive asaccharolytic, obligate anaerobic rod of the phylum Firmicutes, and is considered an emerging pathogen in various oral infections, including periodontitis. We here aimed to perform phylogenetic analysis of a genome-sequenced F. alocis type strain (ATCC 35896; CCUG 47790), as well as nine clinical oral strains that we have independently isolated and sequenced, for identification and deeper characterization of novel genomic elements of virulence in this species. We identified that 60% of the strains carried a gene encoding a hitherto unrecognized member of the large repeats-in-toxins (RTX) family, which we have designated as FtxA. The clinical infection origin of the ftxA-positive isolates largely varied. However, according to MLST, a clear monophylogeny was reveled for all ftxA-positive strains, along with a high co-occurrence of lactate dehydrogenase (ldh)-positivity. Cloning and expression of ftxA in E. coli, and purification of soluble FtxA yielded a protein of the predicted molecular size of approximately 250 kDa. Additional functional and proteomics analyses using both the recombinant protein and the ftxA-positive, and -negative isolates may reveal a possible role and mechanism(s) of FtxA in the virulence properties of F.alocis, and whether the gene might be a candidate diagnostic marker for more virulent strains.
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Affiliation(s)
- Jan Oscarsson
- Division of Oral Microbiology, Department of Odontology, Umeå University, 90187 Umeå, Sweden;
- Correspondence:
| | - Rolf Claesson
- Division of Oral Microbiology, Department of Odontology, Umeå University, 90187 Umeå, Sweden;
| | - Kai Bao
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, 14104 Huddinge, Sweden; (K.B.); (G.N.B.)
| | - Malin Brundin
- Division of Endodontics, Department of Odontology, Umeå University, 90187 Umeå, Sweden;
| | - Georgios N. Belibasakis
- Division of Oral Diseases, Department of Dental Medicine, Karolinska Institutet, 14104 Huddinge, Sweden; (K.B.); (G.N.B.)
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19
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Song MK, Kim HY, Choi BK, Kim HH. Filifactor alocis-derived extracellular vesicles inhibit osteogenesis through TLR2 signaling. Mol Oral Microbiol 2020; 35:202-210. [PMID: 33044804 DOI: 10.1111/omi.12307] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/10/2020] [Accepted: 07/16/2020] [Indexed: 12/18/2022]
Abstract
Filifactor alocis, an asaccharolytic anaerobic Gram-positive rod (AAGPR), is an emerging marker of periodontitis. Severe periodontitis causes destruction of the alveolar bone that supports teeth and can even lead to tooth loss. Based on our previous report that F. alocis-derived extracellular vesicles (FA EVs) contain various effector molecules and have immunostimulatory activity, we investigated the effect of FA EVs on osteogenesis using mouse bone-derived mesenchymal stromal cells (BMSCs). FA EVs dramatically inhibited bone mineralization similar to whole bacteria and reduced the expression levels of osteogenic marker genes. The osteogenic differentiation of TLR2-deficient BMSCs was not inhibited by FA EVs, suggesting that their inhibitory effect on osteogenesis is dependent on TLR2 signaling. FA EVs effectively activated TLR2 downstream signaling of the MAPK and NF-κB pathways. In addition, FA EVs regulated RANKL and OPG gene expression, increasing the RANKL/OPG ratio in BMSCs in a TLR2-dependent manner. Our study suggests that F. alocis-derived EVs interfere with bone metabolism via TLR2 activation, providing insight into the pathogenesis of bone loss associated with periodontitis.
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Affiliation(s)
- Min-Kyoung Song
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
| | - Hyun Young Kim
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Korea
| | - Bong-Kyu Choi
- Department of Oral Microbiology and Immunology, School of Dentistry, Seoul National University, Seoul, Korea
| | - Hong-Hee Kim
- Department of Cell and Developmental Biology, BK21 Program and Dental Research Institute, Seoul National University, Seoul, Korea
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20
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Balmasova IP, Tsarev VN, Arutyunov SD, Babayev EA. [ Filifactor alocis and its role in the etiology of chronic periodontitis]. Stomatologiia (Mosk) 2020; 99:78-82. [PMID: 32608955 DOI: 10.17116/stomat20209903178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The review is devoted to the analysis of modern ideas about the role of bacteria Filifactor alocis in the etiology of chronic periodontitis. The study of these bacteria, discovered in 1985, is complicated by the difficulty of their detection with cultural methods. According to modern researches, the bacteria F.alocis with good reason can be included in the red complex of periodontal pathogens as the most important pathogens of chronic periodontitis. F.alocis is a synergist of such a key pathogen Porphyromonas gingivalis, as well as a frequent satellite of Fusobacterium nucleatum and, somewhat less frequently, Aggregatibacter actinomycetemcomitans. F.alocis is practically not found in healthy people (except for smokers), with a high frequency accompanies the aggressive course of periodontal disease, and also recorded in endodontitis. Due to the ability to participate in the metabolism of arginine, expressed protease activity, a wide range of virulence factors, F.alocis not only colonizes the periodontal tissues, but also significantly affects the formation of the community of periodontal microorganisms (including viruses), contributing to their invasion of epithelial tissues. F. alocis has a number of unique properties, including resistance to oxidative stress conditions in the home defeat, induction of apoptosis of epithelial cells, extracellular matrix degradation of periodontal tissues, activation of proinflammatory cytokines formulation in sites of its presence, suppression of protective reactions of neutrophilic granulocytes, inhibition of the process of complement activation.
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Affiliation(s)
- I P Balmasova
- Moscow State Medical and Dental University named after A.I. Evdokimov, Moscow, Russia
| | - V N Tsarev
- Moscow State Medical and Dental University named after A.I. Evdokimov, Moscow, Russia
| | - S D Arutyunov
- Moscow State Medical and Dental University named after A.I. Evdokimov, Moscow, Russia
| | - E A Babayev
- Moscow State Medical and Dental University named after A.I. Evdokimov, Moscow, Russia
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21
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Lee JS, Spooner R, Chowdhury N, Pandey V, Wellslager B, Atanasova KR, Evans Z, Yilmaz Ö. In Situ Intraepithelial Localizations of Opportunistic Pathogens, Porphyromonas gingivalis and Filifactor alocis, in Human Gingiva. Curr Res Microb Sci 2020; 1:7-17. [PMID: 34308393 PMCID: PMC8294339 DOI: 10.1016/j.crmicr.2020.05.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The gingival epithelium serves as a growth reservoir for opportunistic bacteria. Intraepithelial P. gingivalis and F. alocis colonies are detected together in dysbiotic mucosa. Increased metabolically active dual species can lead to higher microvasculature. Invasion of intraepithelial microvessels leads to systemic pathogen dissemination.
Porphyromonas gingivalis and Filifactor alocis are fastidious oral pathogens and etiological agents associated with chronic periodontitis. Although previous studies showed increased levels of the two obligate anaerobic species in periodontitis patients, methodologies for this knowledge were primarily limited to sampling subgingival plaque, saliva, or gingival crevicular fluid. To evaluate the extent to which P. gingivalis and F. alocis may invade the periodontal tissues, an in situ cross-sectional study was comparatively conducted on the gingival biopsy specimens of patients diagnosed with periodontal health or chronic periodontitis. Immunostained tissue sections for each organism were imaged by Super-Resolution Confocal Scanning Microscopy to determine the relative presence and localization of target bacterial species. Fluorescence-in-situ-hybridization (FISH) coupled with species specific 16S rRNA method was utilized to confirm whether detected bacteria were live within the tissue. In periodontitis, P. gingivalis and F. alocis revealed similarly concentrated localization near the basement membrane or external basal lamina of the gingival epithelium. The presence of both bacteria was significantly increased in periodontitis vs. healthy tissue. However, P. gingivalis was still detected to an extent in health tissue, while only minimal levels of F. alocis were spotted in health. Additionally, the micrographic analyses displayed heightened formation of epithelial microvasculature containing significantly co-localized and metabolically active dual species within periodontitis tissue. Thus, this study demonstrates, for the first-time, spatial arrangements of P. gingivalis and F. alocis in both single and co-localized forms within the complex fabric of human gingiva during health and disease. It also exhibits critical visualizations of co-invaded microvascularized epithelial layer of the tissue by metabolically active P. gingivalis and F. alocis from patients with severe periodontitis. These findings collectively uncover novel visual evidence of a potential starting point for systemic spread of opportunistic bacteria during their chronic colonization in gingival epithelium.
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Affiliation(s)
- Jaden S Lee
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
| | - Ralee Spooner
- Department of Stomatology, Division of Periodontics, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA.,Lieutenant, Dental Corps, United States Navy, Marine Corps Air Ground Combat Center, Twentynine Palms, California, 92278, USA
| | - Nityananda Chowdhury
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
| | - Vivek Pandey
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
| | - Bridgette Wellslager
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
| | - Kalina R Atanasova
- Department of Periodontology, University of Florida, Gainesville, Florida, 32611, USA
| | - Zachary Evans
- Department of Stomatology, Division of Periodontics, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
| | - Özlem Yilmaz
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, South Carolina, 29425, USA.,Department of Microbiology & Immunology, Medical University of South Carolina, Charleston, South Carolina, 29425, USA
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Hishiya N, Uno K, Amano M, Asada K, Masui K, Ishida Y, Suzuki Y, Hirai N, Nakano A, Nakano R, Kasahara K, Yano H, Mikasa K. Filifactor alocis brain abscess identified by 16S ribosomal RNA gene sequencing: A case report. J Infect Chemother 2019; 26:305-307. [PMID: 31711830 DOI: 10.1016/j.jiac.2019.09.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/16/2019] [Accepted: 09/24/2019] [Indexed: 10/25/2022]
Abstract
We report a clinical case of Filifactor alocis brain abscess in an 85-year-old man who had decayed teeth 1 week prior. In this case, the abscess was surgically drained after empirical antibiotics had been initiated. Although the causative organism could not be identified by culture, F. alocis was detected via 16S ribosomal RNA (16S rRNA) gene sequencing of the pus isolated from the abscess. The patient recovered without serious sequelae after surgical drainage and prolonged antibiotic treatment, including metronidazole, ceftriaxone and meropenem for 8 weeks. The findings in this case emphasize that 16S rRNA gene sequencing allows bacterial diagnosis of brain abscess when phenotypic identification fails, such as in cases where patients are undergoing antimicrobial treatment at the time of sampling or where patients are infected with fastidious organisms.
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Affiliation(s)
- Naokuni Hishiya
- Department of Infectious Diseases, Minami Nara General Medical Center, Nara, Japan.
| | - Kenji Uno
- Department of Infectious Diseases, Minami Nara General Medical Center, Nara, Japan
| | - Masayuki Amano
- Department of General Medicine, Minami Nara General Medical Center, Nara, Japan
| | - Kiyokazu Asada
- Department of Neurosurgery, Minami Nara General Medical Center, Nara, Japan
| | - Katsuya Masui
- Department of Neurosurgery, Minami Nara General Medical Center, Nara, Japan
| | - Yasuhito Ishida
- Department of Neurosurgery, Minami Nara General Medical Center, Nara, Japan
| | - Yuki Suzuki
- Department of Microbiology and Infectious Diseases, Nara Medical University, Nara, Japan
| | - Nobuyasu Hirai
- Center for Infectious Diseases, Nara Medical University, Nara, Japan
| | - Akiyo Nakano
- Department of Microbiology and Infectious Diseases, Nara Medical University, Nara, Japan
| | - Ryuichi Nakano
- Department of Microbiology and Infectious Diseases, Nara Medical University, Nara, Japan
| | - Kei Kasahara
- Center for Infectious Diseases, Nara Medical University, Nara, Japan
| | - Hisakazu Yano
- Department of Microbiology and Infectious Diseases, Nara Medical University, Nara, Japan
| | - Keiichi Mikasa
- Center for Infectious Diseases, Nara Medical University, Nara, Japan
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Nokhbehsaim M, Nogueira AVB, Damanaki A, Dalagiorgou G, Eick S, Adamopoulos C, Piperi C, Basdra EK, Papavassiliou AG, Deschner J. Regulation of matrix metalloproteinase-1 by Filifactor alocis in human gingival and monocytic cells. Clin Oral Investig 2019; 24:1987-1995. [PMID: 31444694 DOI: 10.1007/s00784-019-03062-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/14/2019] [Indexed: 02/02/2023]
Abstract
OBJECTIVES Periodontitis is a highly prevalent chronic inflammatory disease caused by periodontopathogens, such as Filifactor alocis. This study sought to examine the matrix metalloproteinase (MMP)-1 synthesis by monocytic and fibroblastic cells in response to F. alocis and to unravel the underlying cellular mechanisms. MATERIAL AND METHODS Gingival biopsies from periodontally healthy and periodontitis individuals were analyzed for the presence of F. alocis and MMP-1 by RT-PCR. Human gingival fibroblastic (HGF-1) and monocytic (THP-1) cells were stimulated with F. alocis in the presence and absence of a blocking toll-like receptor (TLR)2 antibody or specific inhibitors against MAPKs. MMP-1 expression and protein levels were studied by RT-PCR and ELISA, respectively. RESULTS F. alocis was highly prevalent in biopsies from periodontitis patients but barely present in the healthy gingiva. Significantly higher MMP-1 expression levels were found in the inflamed gingiva as compared with healthy biopsies. F. alocis caused a significant and dose-dependent MMP-1 upregulation in both cells. The stimulatory effect of F. alocis on MMP-1 was TLR2- and MAPK-dependent and more pronounced on THP-1 cells as compared with HGF-1 cells. CONCLUSIONS Our results demonstrate that F. alocis and MMP-1 are more prevalent at periodontitis sites. Additionally, our study provides original evidence that F. alocis can stimulate MMP-1 production by fibroblastic and monocytic cells, suggesting that F. alocis may contribute to periodontal breakdown through MMP-1. CLINICAL RELEVANCE F. alocis and MMP-1 are linked to each other and key players in periodontitis, which may have significant implications for future diagnostic and treatment strategies.
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Affiliation(s)
- Marjan Nokhbehsaim
- Section of Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, 53111, Germany
| | - Andressa V B Nogueira
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Augustusplatz 2, 55131, Mainz, Germany.
| | - Anna Damanaki
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Augustusplatz 2, 55131, Mainz, Germany
| | - Georgia Dalagiorgou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 157 72, Athens, Greece
| | - Sigrun Eick
- Department of Periodontology, Laboratory of Oral Microbiology, University of Bern, Bern, 3010, Switzerland
| | - Christos Adamopoulos
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 157 72, Athens, Greece
| | - Christina Piperi
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 157 72, Athens, Greece
| | - Efthimia K Basdra
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 157 72, Athens, Greece
| | - Athanasios G Papavassiliou
- Department of Biological Chemistry, Medical School, National and Kapodistrian University of Athens, 157 72, Athens, Greece
| | - James Deschner
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Augustusplatz 2, 55131, Mainz, Germany
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24
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Zeller I, Malovichko MV, Hurst HE, Renaud DE, Scott DA. Cigarette smoke reduces short chain fatty acid production by a Porphyromonas gingivalis clinical isolate. J Periodontal Res 2019; 54:566-571. [PMID: 30982987 PMCID: PMC6776670 DOI: 10.1111/jre.12660] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 02/13/2019] [Accepted: 03/18/2019] [Indexed: 01/13/2023]
Abstract
Objectives We hypothesized that short chain fatty acid (SCFA) production by oral pathogens is suppressed by exposure to cigarette smoke extract (CSE). Background Tobacco smoking is a major risk factor for plaque‐induced periodontal diseases. Despite increased disease susceptibility, overt oral inflammation is suppressed in smokers, presenting a diagnostic conundrum. Bacterial‐derived SCFAs can penetrate into oral tissues where they influence multiple components of immune and healing responses. Indeed, the SCFA burden has been correlated with the inflammatory condition of the gingiva. However, the influence of cigarette consumption on SCFA production is unknown. Methods GC/MS was employed to monitor the production of several SCFAs (propionic acid, isobutyric acid, butyric acid, and isovaleric acid) by representative anaerobic oral pathogens (Filifactor alocis 35896, Fusobacterium nucleatum 25586, Porphyromonas gingivalis 33277) that were exposed, or not, to a physiologically relevant dose of CSE (2000 ng/ml nicotine equivalents) generated from 3R4F reference cigarettes. Results The growth of all three bacterial species was unaffected by CSE. The capacity to produce SCFAs by these bacteria was highly varied. F alocis produced the highest concentration of a specific SCFA (butyrate); P gingivalis provided the most robust overall SCFA signal, while F alocis and F nucleatum did not release detectable levels of isobutyrate or isovalerate. As P gingivalis 33277 was the broadest SCFA producer, three low‐passage clinical isolates (10208C, 5607, and 10512) were also examined. Compared to unconditioned microbes, reduced SCFA release was apparent in CSE‐exposed low‐passage clinical isolates of P gingivalis which reached significance for one of the three isolates (propionic, isobutyric, butyric, and isovaleric acids, all P < 0.05). Conclusions There is high disparity in the SCFA profiles of variant chronic periodontitis‐associated bacteria, while CSE exposure reduces SCFA production by a specific clinical strain of P gingivalis. If the latter phenomenon occurs in vivo, a reduced SCFA burden may help explain the reduced vascular response to dental plaque in tobacco smokers.
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Affiliation(s)
- Iris Zeller
- Departments of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, Kentucky
| | - Marina V Malovichko
- University of Louisville Superfund Research Center and Envirome Institute, University of Louisville, Louisville, Kentucky.,American Heart Association Tobacco Regulatory Science and Addiction Center, University of Louisville, Louisville, Kentucky
| | - Harrell E Hurst
- Pharmacology and Toxicology, University of Louisville, Louisville, Kentucky
| | - Diane E Renaud
- Departments of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, Kentucky
| | - David A Scott
- Departments of Oral Immunology and Infectious Diseases, University of Louisville, Louisville, Kentucky
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25
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Armstrong CL, Klaes CK, Vashishta A, Lamont RJ, Uriarte SM. Filifactor alocis manipulates human neutrophils affecting their ability to release neutrophil extracellular traps induced by PMA. Innate Immun 2018; 24:210-220. [PMID: 29649915 PMCID: PMC6410572 DOI: 10.1177/1753425918767507] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Neutrophils operate at the site of injury or inflammation in the periodontal
pocket to ensure periodontal health and clearance of bacterial pathogens.
Filifactor alocis is recently identified as a potential
periodontal pathogen, and in this study, we assessed the formation of neutrophil
extracellular traps (NETs), in response to the presence of the
organism. NET formation by human neutrophils was not
induced when challenged with F. alocis, independent of
opsonization, viability, time, or bacterial dose. F. alocis
also failed to induce NETs from TNF-α-primed neutrophils and did not induce the
release of extracellular neutrophil elastase. However, significant NET induction
was observed when neutrophils were challenged with Streptococcus
gordonii or Peptoanaerobacter stomatis, In
addition, co-infection studies revealed that the presence of F.
alocis with S. gordonii or P.
stomatis does not enhance or reduce NETs. Additionally, F.
alocis failed to impact pre-formed NETs induced by either
S. gordonii or P. stomatis. Pretreatment
with F. alocis prior to stimulation with phorbol 12-myristate
13-acetate (PMA), S. gordonii, or P. stomatis
revealed that the bacterium is capable of reducing only PMA but not S.
gordonii or P. stomatis NET formation. These
results indicate that F. alocis manipulates neutrophils,
inhibiting the triggering of NET induction.
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Affiliation(s)
| | | | | | - Richard J Lamont
- 3 Department of Oral Immunology and Infectious Diseases, University of Louisville, USA
| | - Silvia M Uriarte
- 1 Department of Microbiology and Immunology, University of Louisville, USA.,2 Department of Medicine, University of Louisville, USA.,3 Department of Oral Immunology and Infectious Diseases, University of Louisville, USA
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26
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Aruni AW, Mishra A, Dou Y, Chioma O, Hamilton BN, Fletcher HM. Filifactor alocis--a new emerging periodontal pathogen. Microbes Infect 2015; 17:517-30. [PMID: 25841800 DOI: 10.1016/j.micinf.2015.03.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/16/2015] [Accepted: 03/23/2015] [Indexed: 02/06/2023]
Abstract
Filifactor alocis, a previously unrecognized Gram-positive anaerobic rod, is now considered a new emerging pathogen that may play a significant role in periodontal disease. F. alocis' unique characteristics and variations at the molecular level that may be responsible for the functional changes required to mediate the pathogenic process are discussed.
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Affiliation(s)
- A Wilson Aruni
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA
| | - Arunima Mishra
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA
| | - Yuetan Dou
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA
| | - Ozioma Chioma
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA
| | - Brittany N Hamilton
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA
| | - Hansel M Fletcher
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, CA 92354, USA; Institute of Oral Biology, Kyung Hee University, Seoul, Republic of Korea.
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Abstract
BACKGROUND While the oral cavity harbors more than 680 bacterial species, the interaction and association of selected bacterial species play a role in periodontal diseases. Bacterial species including Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia, a consortium previously designated as the "red complex" is now being expanded to include other new emerging pathogens that are significantly associated with periodontal disease. HIGHLIGHT In addition to novel mechanisms for oxidative resistance of individual species, community dynamics may lead to an overall strategy for survival in the inflammatory environment of the periodontal pocket. Complex systems controlled by response regulators protect against oxidative and nitrosative stress. CONCLUSION The combination of these multifaceted strategies would provide a comprehensive defense and support system against the repetitive host immune response to promote microbial persistence and disease.
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Affiliation(s)
- Leroy G Henry
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
| | - Marie-Claire Boutrin
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
| | - Wilson Aruni
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
| | - Antonette Robles
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
| | - Alexia Ximinies
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
| | - Hansel M Fletcher
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California 92350
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