RESUMEN
BACKGROUND AND OBJECTIVE: The potential of probiotics on the prevention and control of periodontitis and other chronic inflammatory conditions has been suggested. Lactobacillus and Bifidobacterium species influence P. gingivalis interaction with gingival epithelial cells (GECs) but may not act in a unique way. In order to select the most appropriate probiotic against P. gingivalis, we aimed to evaluate the effect of several strains on Porphyromonas gingivalis biofilm formation and transcription virulence-associated factors (PgVAFs). METHODS: Cell-free pH neutralized supernatants (CFS) and living Lactobacillus spp. and Bifidobacterium spp. were tested against P. gingivalis ATCC 33277 and W83, in mono- and multi-species (with Streptococcus oralis and S. gordonii) biofilms. Relative transcription of P. gingivalis genes (fimA, mfa1, kgp, rgp, ftsH and luxS) was determined in biofilms and under GECs co-infection. RESULTS: Probiotics CFS reduced P. gingivalis ATCC 33277 levels in mono-species biofilms and living probiotics reduced P. gingivalis abundance in multi-species biofilms. L. acidophilus LA5 down-regulated transcription of most PgVAFs in biofilms and GECs. CONCLUSIONS: Probiotics affect P. gingivalis biofilm formation by down-regulating overall PgVAFs with the most pronounced effect observed for L. acidophilus LA5.
RESUMEN
Porphyromonas gingivalis is a keystone pathogen in periodontitis. Analysis of the immunogenicity of its virulence factors may provide insight into the host response to this infection. The Kgp12 (IEDB Epitope ID 763561), an epitope of Lys-gingipain (Kgp) virulence factor from P. gingivalis ATCC 33277, elicits an immunoglobulin G (IgG) immunoreactivity with low cross-reactivity and, therefore, more specificity. The aim of the present study was to determine in silico the localization of Kgp12 within the protein and to evaluate the IgG host response to this novel Kgp peptide through its capacity to differentiate individuals with different periodontal status. Sera of 71 volunteers were tested by indirect ELISA to detect the IgG immunoreactivity specific to Kgp12, as well as to the protein HmuY and to the sonicated total extract of P. gingivalis ATCC33277, both used as gold standard. The participants had no systemic disease and were classified according to periodontal clinical parameters to comparison, firstly, into periodontitis (P) and without periodontitis (WP) groups and, secondly, into periodontitis (P), gingivitis (G) and clinically health (CH) ones. All the antigens tested, Kgp12 (p = 0.02), HmuY (p = 0.00) and P. gingivalis extract (p = 0.03), could differentiate P from WP groups considering IgG serum levels. P group also had higher IgG levels specific to Kgp12 (p = 0.03), HmuY (p < 0.01) and P. gingivalis extract (p = 0.01) when compared to G group. We conclude that the Kgp12 synthetic peptide was useful to detect the IgG-mediated host response signaling that it is a promising epitope to analyze the immunogenicity of P. gingivalis.
Asunto(s)
Infecciones por Bacteroidaceae/metabolismo , Infecciones por Bacteroidaceae/microbiología , Cisteína-Endopeptidasas Gingipaínas/metabolismo , Inmunoglobulina G/inmunología , Fragmentos de Péptidos/metabolismo , Periodontitis/etiología , Porphyromonas gingivalis/enzimología , Infecciones por Bacteroidaceae/inmunología , Bases de Datos de Proteínas , Susceptibilidad a Enfermedades , Epítopos/inmunología , Femenino , Cisteína-Endopeptidasas Gingipaínas/química , Cisteína-Endopeptidasas Gingipaínas/inmunología , Humanos , Inmunoglobulina G/sangre , Masculino , Modelos Moleculares , Fragmentos de Péptidos/química , Fragmentos de Péptidos/inmunología , Porphyromonas gingivalis/inmunología , Transporte de Proteínas , Relación Estructura-ActividadRESUMEN
Porphyromonas gingivalis (Pg) is one of the main pathogens in chronic periodontitis (CP). Studies on the immunogenicity of its virulence factors may contribute to understanding the host response to infection. The present study aimed to use in silico analysis as a tool to identify epitopes from Lys-gingipain (Kgp) and neuraminidase virulence factors of the Pg ATCC 33277 strain. Protein sequences were obtained from the NCBI Protein Database and they were scanned for amino acid patterns indicative of MHC II binding using the MHC-II Binding Predictions tool from the Immune Epitope Database (IEDB). Peptides from different regions of the proteins were chemically synthesized and tested by the indirect ELISA method to verify IgG immunoreactivity in serum of subjects with CP and without periodontitis (WP). T cell epitope prediction resulted in 16 peptide sequences from Kgp and 18 peptide sequences from neuraminidase. All tested Kgp peptides exhibited IgG immunoreactivity whereas tested neuraminidase peptides presented low IgG immunoreactivity. Thus, the IgG reactivity to Kgp protein could be reaffirmed and the low IgG reactivity to Pg neuraminidase could be suggested. The novel peptide epitopes from Pg were useful to evaluate its immunoreactivity based on the IgG-mediated host response. In silico analysis was useful for preselecting epitopes for immune response studies in CP.
RESUMEN
Objetivo: Testar a hipótese de que drogas anti-hipertensivas inibidoras da enzima conversora da angiotensina (iECA) causam aumento de prevalência e gravidade da periodontite crônica. Metodologia: Sessenta e cinco pacientes hipertensos (trinta no grupo teste e trinta e cinco no controle) que fazem uso regular de anti-hipertensivos participaram desse estudo. Dados clínicos periodontais, incluindo nível clínico de inserção (NCI), profundidade de bolsa à sondagem (PBS) e índices de sangramento à sondagem (ISS), de placa visível (IPV), de cálculo (IC) e de sangramento marginal (ISM), obtidos de 6 sítios/dente, foram submetidos a testes estatísticos paramétricos e não-paramétricos, incluindo o Modelamento Linear Generalizado com Equações de Estimação Generalizada (GLM/GEE). Resultados: Ambos os grupos apresentaram médias de idade e de tempo de terapia anti-hipertensiva semelhantes, porém diferiram na renda média e no IPV. Os pacientes que fazem uso dos iECA tiveram condições periodontais piores e chances até 4 vezes maiores de apresentar PBS e NCI ≥ 5mm. Além disso, observou-se que a prevalência de periodontite crônica neste grupo foi o dobro da apresentada pelo grupo controle (63,4 % vs. 31,5 %, P < 0,001). Conclusão: Pacientes sob terapia anti-hipertensiva com iECA apresentam prevalência e gravidade aumentadas de periodontite crônica. (AU)
Aim: The objective of this study was to test the hypothesis that angiotensin-convertingenzyme inhibitor (ACEi) drugs lead to higher prevalence and severity of chronic periodontitis. Methodology: Sixty-five individuals with high blood pressure who make regular use of antihypertensive drugs (thirty patients who used ACEi and thirty-five controls using a different antihypertensive treatment), were selected to participate. Periodontal clinical data, including clinical attachment loss (CAL), probing pocket depth (PPD), and the presence of bleeding on probing (BOP), visible plaque (VP), calculus (CI) and marginal gingival bleeding (MGB) obtained from 6 sites per tooth, were submitted to parametric or non-parametric statistical tests, including the General Linear Model with Generalized Estimated Equations (GLM/GEE) to compare the odds ratio between groups for presenting PPD and CAL ≥ 5 mm. Results: Both groups showed similar mean age and mean length of anti-hypertensive therapy, although mean income and VP differed between groups. Patients under ACEi therapy showed worsened periodontal conditions as well as an odds ratio around four for presenting PPD and CAL ≥ 5mm. Furthermore, chronic periodontitis was two times more prevalent in patients taking ACEi drugs compared to controls (63.4 % vs. 31.5 %, P < 0,001). Conclusion: Patients under antihypertensive therapy with ACEi drugs show increased prevalence and severity of chronic periodontitis. (AU)