lipoteichoic-acid and Gingivitis

In previous works we have shown that a low-molecular-mass (LMM) fraction from mushroom (Lentinus edodes) homogenate interferes with binding of Streptococcus mutans to hydroxyapatite and Prevotella intermedia to gingival cells. Additionally, inhibition of biofilm formation of both odonto- and periodonto-pathogenic bacteria and detachment from preformed biofilms have been described for this compound. Further purification of mushroom extract has been recently achieved and a sub-fraction (i.e. # 5) has been identified as containing the majority of the mentioned biological activities. The aim of this study was to characterise the bacterial receptors for the purified mushroom sub-fraction #5 in order to better elucidate the mode of action of this compound when interfering with bacterial adhesion to host surfaces or with bacteria-bacteria interactions in the biofilm state.. Candidate bacterial molecules to act as target of this compound were bacterial surface molecules involved in cell adhesion and biofilm formation, and, thus, we have considered cell wall associated proteins (CWPs), teichoic acid (TA) and lipoteichoic acid (LTA) of S. mutans, and outer membrane proteins (OMPs) and lipopolysaccharide (LPS) of P. intermedia.. Fifteen S. mutans CWPs and TA were capable of binding sub-fraction #5, while LTA did not. As far as P. intermedia is concerned, we show that five OMPs interact with sub-fraction # 5. Capacity of binding to P. intermedia LPS was also studied but in this case negative results were obtained.. Binding sub-fraction # 5 to surface molecules of S. mutans or P. intermedia may result in inactivation of their physiological functions. As a whole, these results indicate, at molecular level, the bacterial surface alterations affecting adhesion and biofim formation. For these antimicrobial properties, the compound may find use in daily oral hygiene.

Topics: Agaricales; Anti-Bacterial Agents; Bacteria; Bacterial Adhesion; Bacterial Proteins; Biofilms; Biological Products; Dental Caries; Gingivitis; Lipopolysaccharides; Membrane Proteins; Prevotella; Shiitake Mushrooms; Streptococcus mutans; Teichoic Acids

IgG antibody levels to lipoteichoic acid (LTA), prepared from Streptococcus mutans cells, were determined by enzyme-linked immunosorbent assay in serum samples from 149 subjects. An extract from Bacteroides gingivalis and lipopolysaccharide from Escherichia coli 055:B5 served as control antigens. The reference group comprised 28 systemically and periodontally healthy adults. The main test groups were: 52 persons with gingivitis only, and 69 patients with periodontitis. Within those groups, 37 patients had insulin-dependent diabetes mellitus, another 20 patients were prospective or renal transplant recipients. The periodontitis patient group showed significantly (p less than 0.05) higher mean antibody value and higher frequency of extreme antibody responses to both LTA and B. gingivalis than the gingivitis group. LPS did not discriminate between the groups. Multiple regression analysis with gingivitis scores as the dependent variable selected plaque scores, anti-LTA antibody values and general health status as significant (p less than 0.05) regressors. The variance in radiographical alveolar bone loss was significantly (p less than 0.05) explained by age and by antibody values to B. gingivalis and to LTA. The patients with extreme immunological responsiveness to LTA or to B. gingivalis had about twice as much alveolar bone loss as those with normal serological reactivity. The results support the contention that LTA modulates the progression of periodontitis in humans.

Topics: Adolescent; Adult; Antigen-Antibody Reactions; Bone Resorption; Diabetes Mellitus, Type 1; Enzyme-Linked Immunosorbent Assay; Gingivitis; Humans; Immunoglobulin G; Immunosuppression Therapy; Kidney Failure, Chronic; Lipopolysaccharides; Middle Aged; Periodontitis; Teichoic Acids

Topics: Adolescent; Adult; Antibodies, Bacterial; Antigen-Antibody Reactions; Child; Child, Preschool; Dental Plaque; Enzyme-Linked Immunosorbent Assay; Gingivitis; Humans; Immunoglobulin G; Lipopolysaccharides; Middle Aged; Phosphatidic Acids; Staphylococcus aureus; Streptococcus mutans; Teichoic Acids

We investigated the bacteriolytic activity of gingival crevicular fluid (CF) on 14C-labeled Streptococcus faecalis, Streptococcus mutans, Staphylococcus aureus, and on whole dental plaque. CF was collected from 100 healthy donors pooled and centrifuged at 200 g. CF supernate and a frozen and thawed extract of the pellet were interacted with the different bacterial strains, while Streptococcus faecalis and Staphylococcus aureus released 60% and 75% of the radioactive label, only 38% of it was solubilized from Streptococcus mutans, following their incubation with the CF supernate. The findings agreed with results obtained by interacting bacteria with a frozen and thawed lysate of human peripheral blood leukocytes. On the other hand, extracts from frozen and thawed CF pellet were inactive. Further, lipoteichoic acid and lipopolysaccharide were released by CF from Gram-positive and Gram-negative bacteria, respectively. The role of bacteriolytic factors, present in CF, as a result of the interaction between microorganisms and leukocytes at inflammatory sites is discussed.

Topics: Actinomyces; Bacteriolysis; Enterococcus faecalis; Gingival Crevicular Fluid; Gingivitis; Immune Sera; Lipopolysaccharides; Lysosomes; Phosphatidic Acids; Staphylococcus aureus; Streptococcus mutans; Teichoic Acids