No abstract available.
Fusobacterium nucleatum* ; Fusobacterium* ; Immunization* ; Porphyromonas gingivalis* ; Porphyromonas*

No abstract available.
Biofilms* ; Fusobacterium nucleatum* ; Fusobacterium* ; Porphyromonas gingivalis* ; Porphyromonas*

Adhesins, Bacterial ; Biomedical Research ; Fusobacterium nucleatum

The purpose of this study was to isolate and characterize the Fusobacterium nucleatum (F. nucleatum) from subgingival plaque in Korean periodontitis patients. The subgingival plaque samples of periodontitis patient were collected with sterilized paper point. The paper point was put into reduced transfer medium and then immediately transferred to laboratory. The subgingival samples were diluted by 10,000 folds and plated on F. nucleatum-selective media agar plate. The plates were incubated at 37degrees C in an anaerobic chamber for 3 days. The violet-colored colonies were selected and subjected to further verification whether those are F. nucleatum or not. For further confirmation, 16S rRNA genes (rDNA) were cloned from each of bacterial clones and determined sequence of 16S rDNA. In this study, we found 17 distinct clinical isolates of F. nucleatum from subgingival plaque. The clinical isolates will be a useful in various studies in periodontology.
Agar ; Clone Cells ; DNA, Ribosomal ; Fusobacterium nucleatum* ; Fusobacterium* ; Genes, rRNA ; Humans ; Periodontitis

Lemierre’s syndrome (LS) is a rare life-threatening infective condition typically starting with an oropharyngeal infection causing thrombophlebitis and metastatic abscesses. The most common aetiology of LS is Fusobacterium necrophorum; however, it can also occur after infection with other organisms. LS mainly affects young healthy adults. The initial infection site can be in the head and neck or in the abdomen. The morbidity rate of this disease is high despite aggressive treatments. In this article, we report a 63-year-old male patient with uncontrolled diabetes mellitus, presenting with Klebsiella pneumoniae infection-induced necrotizing fasciitis on the right side of the neck, leading to LS.
Fasciitis, Necrotizing ; Lemierre Syndrome ; Fusobacterium necrophorum ; Klebsiella pneumoniae

Multiple periodontal pathogens sequentially colonize the subgingival niche during the conversion from gingivitis to destructive periodontal disease. An animal model of sequential immunization with key periodontal pathogens has been developed to determine whether T and B lymppocyte effector functions are skewed and fail to protect the host from pathogenic challenge. The present study was performed to evaluate immunomodulatory effect of exposure to Fusobacterium nucleatum(F. nucleatum) prior to Porphyromonas gingivalis(P.gingivalis). Group 1(control) mice were immunized with phosphate-buffered saline, Group 2 were immunized with F. nucleatum prior to P. gingivalis, while Group 3 were immunized P. gingivalis alone. All the T cell clones derived from Group 2 demonstrated type 2 helper T cell clone(Th2 subsets), while those from Group 3 mice demonstrated Th1 subsets. Exposure of mice to F. nucleatum prior to P. gingivalis interfered with opsonophagocytosis function of sera against P. gingivalis. In adoptive T cell transfer experiments, in vivo protective capacity type 2 helper T cell clones(Th2) from Group 2 was significantly lower than type 1 helper T cell clones(Th1) from Group 3 against the lethal dose infection of P. gingivalis. Western blot analysis indicated the different pattern of recognition of P. gingivalis fimbrial proteins between sera from Group 2 and Group 3. In conclusion, these study suggest that colonization of the subgingival niche by F. nucleatum prior to the periodontal pathogen, P. gingivalis, modulates the host immune responses to P. gingivalis at humoral, cellular and molecular levels.
Animals ; Blotting, Western ; Clone Cells ; Colon ; Fusobacterium nucleatum* ; Fusobacterium* ; Gingivitis ; Immunization ; Mice* ; Models, Animal ; Periodontal Diseases ; Porphyromonas gingivalis* ; Porphyromonas*

PURPOSE: The goal of this study was to develop and validate a standardized in vitro pathogenic biofilm attached onto saliva-coated surfaces. METHODS: Fusobacterium nucleatum (F. nucleatum) and Porphyromonas gingivalis (P. gingivalis) strains were grown under anaerobic conditions as single species and in dual-species cultures. Initially, the bacterial biomass was evaluated at 24 and 48 hours to determine the optimal timing for the adhesion phase onto saliva-coated polystyrene surfaces. Thereafter, biofilm development was assessed over time by crystal violet staining and scanning electron microscopy. RESULTS: The data showed no significant difference in the overall biomass after 48 hours for P. gingivalis in single- and dual-species conditions. After adhesion, P. gingivalis in single- and dual-species biofilms accumulated a substantially higher biomass after 7 days of incubation than after 3 days, but no significant difference was found between 5 and 7 days. Although the biomass of the F. nucleatum biofilm was higher at 3 days, no difference was found at 3, 5, or 7 days of incubation. CONCLUSIONS: Polystyrene substrates from well plates work as a standard surface and provide reproducible results for in vitro biofilm models. Our biofilm model could serve as a reference point for studies investigating biofilms on different surfaces.
Bacterial Adhesion ; Biofilms ; Biomass ; Fusobacterium nucleatum ; Fusobacterium ; Gentian Violet ; In Vitro Techniques ; Microscopy, Electron, Scanning ; Polystyrenes ; Porphyromonas gingivalis ; Porphyromonas

Fusobacterium nucleatum (F. nucleatum) is an early pathogenic colonizer in periodontitis, but the host response to infection with this pathogen remains unclear. In this study, we built an F. nucleatum infectious model with human periodontal ligament stem cells (PDLSCs) and showed that F. nucleatum could inhibit proliferation, and facilitate apoptosis, ferroptosis, and inflammatory cytokine production in a dose-dependent manner. The F. nucleatum adhesin FadA acted as a proinflammatory virulence factor and increased the expression of interleukin(IL)-1β, IL-6 and IL-8. Further study showed that FadA could bind with PEBP1 to activate the Raf1-MAPK and IKK-NF-κB signaling pathways. Time-course RNA-sequencing analyses showed the cascade of gene activation process in PDLSCs with increasing durations of F. nucleatum infection. NFκB1 and NFκB2 upregulated after 3 h of F. nucleatum-infection, and the inflammatory-related genes in the NF-κB signaling pathway were serially elevated with time. Using computational drug repositioning analysis, we predicted and validated that two potential drugs (piperlongumine and fisetin) could attenuate the negative effects of F. nucleatum-infection. Collectively, this study unveils the potential pathogenic mechanisms of F. nucleatum and the host inflammatory response at the early stage of F. nucleatum infection.
Humans ; Fusobacterium nucleatum/metabolism* ; NF-kappa B/metabolism* ; Periodontal Ligament/metabolism* ; Signal Transduction ; Fusobacterium Infections/pathology* ; Stem Cells/metabolism*

Selecting an appropriate antigen with optimal immunogenicity and physicochemical properties is a pivotal factor to develop a protein based subunit vaccine. Despite rapid progress in modern molecular cloning and recombinant protein technology, there remains a huge challenge for purifying and using protein antigens rich in hydrophobic domains, such as membrane associated proteins. To overcome current limitations using hydrophobic proteins as vaccine antigens, we adopted in silico analyses which included bioinformatic prediction and sequence-based protein 3D structure modeling, to develop a novel periodontitis subunit vaccine against the outer membrane protein FomA of Fusobacterium nucleatum. To generate an optimal antigen candidate, we predicted hydrophilicity and B cell epitope parameter by querying to web-based databases, and designed a truncated FomA (tFomA) candidate with better solubility and preserved B cell epitopes. The truncated recombinant protein was engineered to expose epitopes on the surface through simulating amino acid sequence-based 3D folding in aqueous environment. The recombinant tFomA was further expressed and purified, and its immunological properties were evaluated. In the mice intranasal vaccination study, tFomA significantly induced antigen-specific IgG and sIgA responses in both systemic and oral-mucosal compartments, respectively. Our results testify that intelligent in silico designing of antigens provide amenable vaccine epitopes from hard-to-manufacture hydrophobic domain rich microbial antigens.
Animals ; Cloning, Molecular ; Computational Biology ; Computer Simulation* ; Epitopes ; Epitopes, B-Lymphocyte ; Fusobacterium nucleatum* ; Fusobacterium* ; Hydrophobic and Hydrophilic Interactions ; Immunoglobulin A, Secretory ; Immunoglobulin G ; Membrane Proteins ; Mice ; Periodontitis ; Solubility ; Vaccination

Lemierre syndrome is caused by an infection in the oropharyngeal region with subsequent thrombophlebitis in the internal jugular vein. The thrombus from the thrombophlebitis can invade other vital organs, such as liver, lungs, or joints, resulting in secondary infection, which further exacerbates the fatal prognosis of this syndrome. Lemierre syndrome, also called postanginal sepsis or necrobacillosis, was first reported by Dr. Lemierre in 1936. In his report, Lemierre mentioned that out of 20 patients who suffered from this syndrome, only two survived. He also stated that all of the 20 patients complained of infections in the palatine tonsils and developed sepsis and thrombophlebitis in the internal jugular vein. Once called a "forgotten disease," this syndrome showed a very high mortality rate until usage of antibiotics became prevalent. In this case report, the authors present a 71-year-old female patient who suffered from Lemierre syndrome with thrombosis extended to the right sigmoid sinus.
Anti-Bacterial Agents ; Coinfection ; Colon, Sigmoid ; Female ; Fusobacterium Infections ; Fusobacterium necrophorum ; Humans ; Joints ; Jugular Veins ; Lemierre Syndrome ; Liver ; Lung ; Palatine Tonsil ; Prognosis ; Sepsis ; Thrombophlebitis ; Thrombosis