Identification of oral bacteria associated with crevicular epithelial cells from chronic periodontitis lesions

Abstract

Bacterial invasion of host epithelial cells plays an important role in the pathogenesis of periodontal diseases; however, the interactions between subgingival species and the gingival crevice cells are not fully understood. This study determined the prevalence of a group of oral bacterial species on or in epithelial cells derived from periodontal pockets and the gingival crevice of subjects with periodontitis. Samples of epithelial cells were obtained from 120 sites with periodontal pockets ¢4 mm and 92 periodontally healthy sites from 49 patients (mean age 46?3±1?4 years; 43 % males) with chronic periodontitis. Bacteria in or on epithelial cells were separated from unattached bacteria by Percoll density-gradient centrifugation. The presence and levels of 33 oral species were determined in epithelial cell samples by whole genomic DNA probes and the checkerboard method. The most frequently detected species were Porphyromonas gingivalis (42 %), Treponema denticola (38 %), Prevotella intermedia (37 %), Streptococcus intermedius (36 %), Campylobacter rectus (35 %), Streptococcus sanguinis (35 %) and Streptococcus oralis (34 %). Species of Actinomyces were found in low prevalence and levels. The data indicated that there were more micro-organisms on or in epithelial cells obtained from periodontal pockets than from healthy sulci; however, no significant differences regarding the percentage and level of any specific species were found between these sites. Veillonella parvula, S. oralis, Streptococcus gordonii and Streptococcus mitis tended to be more prevalent in sites without disease. These findings demonstrated that a wide range of oral species may be detected on or in crevicular epithelial cells from sites with periodontitis and from periodontally healthy sulci.

Cultivation of a human-associated TM7 phylotype reveals a reduced genome and epibiotic parasitic lifestyle

“…S1). Similarly, strains of A. odontolyticus related to XH001 have been associated with pathogenesis (26). The TM7x/XH001 coculture obtained in this study allowed researchers to examine the virulence potential of TM7x for the first time to our knowledge.…”

“…Bacterial endosymbionts that have lost genes for biosynthesis of amino acids have documented domain-level LGT to the host genome to provide these missing amino acids. N. equitans is an obligate epibiotic parasite that cannot import substrates from the environment, and therefore must stay attached to its host archaeon Ignicoccus to survive (26). Presumably, N. equitans acquires pathways from its host that are not encoded in its tiny genome, which include biosynthesis of amino acids, nucleotides, or cofactors (25).…”

Variabilidad de la síntesis de citoquinas por células dendríticas humanas estimuladas con los distintos serotipos de Aggregatibacter actinomycetecomitans

“…En efecto, en el biofilm subgingival es posible encontrar diferentes concentraciones de bacterias periodonto-patógenas que dependen, por ejemplo, de las condiciones del micro-ambiente local (2) . Además, la concentración y composición del biofilm subgingival no sólo varía entre un individuo sano y un paciente con periodontitis, sino que también entre sitios sanos y lesiones periodontales en el mismo individuo (51) , pudiendo relacionarse directamente con la presencia de un serotipo o bacteria en particular. Así, las variaciones en la frecuencia de detección de A. actinomycetemcomitans entre las distintas formas de periodontitis, la detección en sujetos sanos y la persistencia en el ambiente subgingival de sujetos sanos posterior al tratamiento periodontal podrían deberse a una distribución distinta de sus serotipos dependiente del estado clínico periodontal del sujeto (52) y esta variable distribución estaría asociada a la potencial distinta virulencia y patogenicidad entre estos serotipos bacterianos.…”

Identification and Characterization of an Invasion Antigen B Gene from the Oral Pathogen Campylobacter rectus

“…Campylobacter rectus is a poorly described Gram-negative, oral bacterium that has been implicated as a cause of periodontitis [3][4][5]. Recent studies indicate that women with periodontitis are seven times more likely to experience preterm labor than their healthy counterparts [6,7].…”