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PubMed1998

Measurement of Actinomyces pyogenes specific antibodies in bovine blood samples by an enzyme-linked immunosorbent assay.

In the present investigation Actinomyces pyogenes specific antigens caused an antibody response in the host. This could be determined by two enzyme-linked immunosorbent assays (ELISA) using cell extracts and a haemolysin preparation as antigens. An increased antibody titre was detectable in the sera of cows vaccinated with culture supernatants of A. pyogenes and Peptococcus indolicus, in the sera of cows infected with live cells of A. pyogenes and P. indolicus, in the sera of cows suffering from 'summer mastitis', and in part of the sera of nonvaccinated, apparently healthy cows. However, the titre of the cows that were vaccinated with culture supernatants decreased 8-9 months after inoculation. Because of the wide variation in antibody titre the determination of A. pyogenes specific antibodies seems to be only of limited use for the control of this infection.

Actinomyces↗
PubMed1989

The IUCD-associated incidence of Actinomyces israelii in the female genital tract.

Cervical swabs and in many cases also intrauterine contraceptive devices were examined from 973 women for the presence of Actinomyces israelii. It was detected in 11.6% of these women, the majority of whom were asymptomatic. The detection, however, of A. israelii in the female genital tract was associated with an almost 4-fold increase in the incidence of pelvic inflammatory disease (PID), indicating that colonization may progress to an infection in a small number of women. The incidence of A. israelii in the female genital tract of IUCD wearers was more than doubled when the IUCD was worn for longer than 4 years. The type of IUCD worn did not appear to be an important risk factor. Immunofluorescent staining of cervical smears identified 64% of cases. Specific culturing for A. israelii or cytological screening of Papanicolaou smears in addition were required to increase the isolation rate to nearly 90%.

Actinomyces↗
PubMed2001

The role of fructans on dental biofilm formation by Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus.

Dental plaque biofilm plays a pivotal role in the progression of dental diseases. Polysaccharides are of great importance in the ecology of the dental biofilm. We studied the effect of fructans, glucans and a mixture of both fructans and glucans, synthesized in situ by immobilized fructosyltransferase or glucosyltransferase, on the adhesion of Streptococcus sobrinus, Streptococcus mutans, Streptococcus gordonii and Actinomyces viscosus to hydroxyapatite beads coated with human saliva (sHA). The adhesion of A. viscosus to sHA was found to be fructan-dependent. Adhesion of both S. sobrinus and S. mutans was found to be mediated mainly by glucans, while the adhesion of S. gordonii was found to be both glucan- and fructan-dependent. Treatment with fructanase prior to A. viscosus adhesion resulted in a significant reduction in adhesion to sHA, while adhesion of S. sobrinus, S. mutans and S. gordonii was slightly influenced by fructanase treatment. Treatment with fructanase after adhesion of S. gordonii to sHA resulted in a significant reduction in their adhesion to sHA. Our results show that fructans may play a role in the adhesion and colonization of several cariogenic bacteria to sHA, thus contributing to the formation of dental plaque biofilm.

Actinomyces viscosus↗
PubMed1992

Acid production by Actinomyces viscosus of root surface caries and non-caries origin during glycogen synthesis and degradation at different pH levels.

Actinomyces viscosus strains, freshly isolated from root surface caries lesions and intact root surfaces, were studied for their glycogen synthetic and degradative activities at pH 4.5, 5.0, and 7.0 in a pH-stat. At all three pH levels, root caries origin of A. viscosus synthesized up to three times as much glycogen compared to non-root caries origin. Since root caries origin of A. viscosus strains initially synthesized large amounts of glycogen, a longer period of time was required to deplete this polymer, resulting in an extended period of acid production, even at pH 4.5 and pH 5.0. This study suggests that the ability of A. viscosus of root caries origin to synthesize large quantities of glycogen and subsequently degrade this stored polymer slowly with acid production, at acidic pH levels, may play an important role in the root caries process.

Acids↗
PubMed1987

Proportions of Streptococcus mutans, lactobacilli and Actinomyces spp in root surface plaque.

The incidence of Streptococcus mutans, lactobacilli and Actinomyces was examined in root surface dental plaque from 24 subjects with root surface caries and in 24 subjects with exposed root surfaces as a consequence of periodontitis but without root surface caries. Plaque was collected from the most posterior teeth in each quadrant: in the caries group from carious lesions and in the periodontitis group from buccal root surfaces. There were significantly higher proportions of S. mutans and lactobacilli in dental plaque samples taken from subjects suffering from root surface caries than in samples from subjects without root surface caries. The level of the group A. viscosus/naeslundii in the periodontitis group was higher than that found in the root surface caries group, but the difference was not statistically significant.

Actinomyces↗
PubMed1989

Analysis of the serum antibody responses to type 1 and type 2 fimbriae in mice immunized with Actinomyces viscosus T14V.

The antibody responses of inbred mice immunized with Actinomyces viscosus T14V cells were analyzed using enzyme-linked immunoabsorbent assays (ELISAs) for measuring serum antibodies reactive with A. viscosus T14V cells and type 1 and type 2 fimbriae. In A/J mice immunized intraperitoneally on days 0 and 14, the serum antibody responses approached peak levels during d 19-35, and a dose of 10(8) cells/injection elicited optimal responses. Analysis of the responses of three genetically diverse strains of inbred mice indicated striking variations in the amounts of anti-type 1 (6.5-fold) and anti-type 2 (14.3-fold) antibodies elicited. The observed variations in the magnitude of the anti-fimbrial antibody responses are theoretically of sufficient magnitude to account for significant differences between mouse strains in their ability to inhibit adherence of A. viscosus T14V to saliva-coated hydroxyapatite and other bacteria. These studies provide a model with which the effects of variations in anti-fimbrial antibody responses on bacterial adherence may be analyzed.

Actinomyces↗
PubMed1991

Isolation and characterization of a 180-kiloDalton salivary glycoprotein which mediates the attachment of Actinomyces naeslundii to human buccal epithelial cells.

The adherence of Actinomyces naeslundii to human buccal mucosa is mediated by specific interactions between the bacterial cell surface fimbriae and complementary beta-linked galactoside receptors on the epithelial cell surface. The buccal mucosa and the bacteria that colonize its surface are constantly bathed in saliva. Several salivary components are thought to play an important role in modulating adhesive interactions between oral bacteria and the buccal epithelium. We have observed that pretreatment of isolated buccal epithelial cells (BEC) with human parotid saliva increased the attachment of three different strains of A. naeslundii. By employing affinity chromatography, ion-exchange and high-pressure liquid chromatographic techniques we have isolated a 180 kDa A. naeslundii-binding salivary glycoprotein (An-SPG). This salivary glycoprotein was capable of mediating separate but specific binding interactions with A. naeslundii and BEC. Pretreatment of BEC with increasing amounts of An-SGP resulted in a corresponding increase in the attachment of A. naeslundii. The adherence of A. naeslundii to An-SGP-coated BEC is sensitive to the same inhibitors previously shown to block adherence of A. naeslundii to uncoated BEC, namely lactose- and galactosyl-binding lectins. When a solubilized extract of freshly isolated and washed BEC was reacted on a Western blot with antibodies to An-SGP, a prominent 180 kDa immunoreactive band was detected. Furthermore, the immunoreactive component was demonstrated on the BEC surface when assayed by immunofluorescence using An-SGP-specific antibodies, suggesting that An-SGP or a protein structurally and immunologically identical to the isolated glycoprotein is present on BEC.

Actinomyces↗
PubMed1997

An immunohistochemical study on the localization of Porphyromonas gingivalis, Campylobacter rectus and Actinomyces viscosus in human periodontal pockets.

The localization and distribution of Porphyromonas gingivalis, Campylobacter rectus and Actinomyces viscosus were studied in human periodontal pockets. After obtaining voluntary consent from 9 patients, 12 teeth and their surrounding periodontal tissue with advanced adult periodontitis were extracted carefully so as not to change the structure of the periodontal pockets. The specimens were processed into serial sections. One of the sections was stained with Brown & Brenn-modified Gram stain to observe the distribution of bacteria. The others were stained immunohistochemically by the Labelled Streptavidin Biotin method (LSAB method) using specific rabbit antibodies against selected bacteria. Some bacteria could be found within epithelial cells. P. gingivalis was found in 9/12 of the samples examined. Small aggregates of P. gingivalis were scattered in all parts of the periodontal pockets, and some of these aggregates could be seen in close contact with the epithelium. Conversely, C. rectus was observed in 5/12 of the samples examined and was predominantly located in the middle and deep pocket zones. C. rectus tended to form large clumps in both the tooth-attached and epithelium-associated plaque area. A. viscosus was observed in 7/12 of the samples examined and was localized predominantly in the tooth-attached plaque area, especially in the shallow and middle pocket zones. Although unexpected spills of unattached plaque from periodontal pockets was possible, immunohistochemical staining with species-specific antibodies was extremely sensitive and revealed the localization and the distribution of periodontal disease-associated bacteria in human periodontal pockets.

Actinomyces viscosus↗
PubMed1998

Preparation and characterization of an Actinomyces naeslundii aggregation factor that mediates coaggregation with Porphyromonas gingivalis.

Intergeneric coaggregation is responsible for the complexity of the microbiota in human dental plaque and is believed to be important in the initial bacterial colonization of the human oral cavity. Actinomyces naeslundii, an early colonizer of the tooth surface, may enhance subsequent colonization by Porphyromonas gingivalis which is associated with adult periodontitis. The purpose of this study was to isolate and characterize the A. naeslundii aggregation factor (AnAF) that mediates coaggregation with P. gingivalis. AnAF was isolated from A. naeslundii sonic extract (SE) by gel filtration on a Sephacryl S-400HR, by hydrophobic interaction chromatography on a HiTrap Octyl Sepharose 4FF, and by ion exchange chromatography on a HiTrap Q. The specific activity increased 12-fold with a yield of 2.5%. SDS-PAGE analysis of AnAF revealed a protein band of high molecular weight in excess of 200 kDa. Carbohydrate was detected as the only material coinciding with the protein band, indicating that the AnAF was a glycoprotein. Immunoblotting analysis indicated that AnAF directly bound to P. gingivalis cells. AnAF was sensitive to sodium metaperiodate treatment but not to heat or protease treatments. These results suggest that the AnAF carbohydrate component mediated coaggregation with P. gingivalis cells. AnAF also inhibited coaggregation with other periodontal disease-associated bacteria such as Prevotella intermedia, Fusobacterium nucleatum, Capnocytophaga ochracea, but not streptococci.

Actinomyces↗
PubMed1998

Experimental actinomycosis in mice induced by alginate gel particles containing Actinomyces israelii.

The present study aimed to make an animal model for investigating chronic infection. Bacterial cells of Actinomyces israelii (ATCC 10048) were packed in alginate gel particles and injected intra-peritoneally into BALB/c mice. Actinomycotic lesions were induced efficiently in 9 mice out of 12 after 3 or 9 weeks. Actinomycotic lesions were not produced by injecting a bacterial suspension of A. israelii except in one animal. Neither did injection of gel particles without bacteria induce lesions. Bacteria survived in the lesions for at least 9 weeks after the injection, and serum IgG levels against the bacteria were significantly elevated in the animals, indicating that the bacteria were protected from immunological elimination and activated humoral immunity in the animals. Histopathological observation of the lesion by staining revealed that the bacteria in the lesions were acid-fast and seemed to become resistant to phagocytosis. The bacterial masses were surrounded by inflammatory cells, including polymorphonuclear leukocytes and macrophages, and were separated from the host cells by a fringe-like structure similar to the capsular structure of natural sulfur granules. The present study indicated that the use of an alginate gel was effective in inducing actinomycotic lesions in mice.

Actinomyces↗
PubMed2006

The induction of oral tolerance to Actinomyces viscosus in mice.

OBJECTIVES: To determine whether oral tolerance with the oral bacterium Actinomyces viscosus was inducible in mice. MATERIALS AND METHODS: Mice were intragastrically (i.g.) and then intraperitoneally (i.p.) immunized with heat-killed A. viscosus. A control group of mice received only saline. A delayed type hypersensitivity (DTH) response and the levels of isotype specific antibodies were assessed. Spleen cells from mice that were i.g. immunized with A. viscosus were transferred to A. viscosus-primed mice in vivo and in vitro. Furthermore, mice were i.g. immunized with saline or A. viscosus and then challenged i.p. with saline, A. viscosus, or Porphyromonas gingivalis. RESULTS: Intragastric immunization with A. viscosus suppressed both DTH and serum specific antibodies to A. viscosus. DTH suppression lasted until week 4, while serum immunoglobulin (Ig)A and both IgG and IgM specific antibody levels remained suppressed up to week 8 and 12 respectively. IgG specific antibody suppression was transferable. The DTH response and serum antibodies specific to A. viscosus were suppressed in mice after i.g. challenged with A. viscosus but not P. gingivalis. CONCLUSION: Mucosal presentation of A. viscosus in mice led to the suppression of immune response to this bacterium in an antigen-specific fashion. Tolerance of DTH response was short lived, while suppression of antigen-specific IgG antibodies in mucosally tolerized mice was long-lasting.

Actinomyces viscosus↗
PubMed1977

Bacteriocin from Actinomyces odontolyticus with temperature-dependent killing properties.

A strain of Actinomyces odontolyticus, originally isolated from human dental plaque, produced a non-dialyzable, trypsin-sensitive substance that was bactericidal for certain strains of bifidobacteria at 42 degrees C but not at 37 degrees C. Detectable quantities of the bacteriocin were not produced in liquid media. Experimentally useful yields were obtained by extraction from pour plate cultures of producer cells. At 42 degrees C, exponential killing did not occur until indicator cells had doubled at least once. At 37 degrees C, the bacteriocin effected a transient bacteriostasis. Partially purified concentrates were obtained by diethylaminoethyl-cellulose chromatography, and such material was not inactivated by ribonuclease, deoxyribonuclease, or lipase. Pronase, trypsin, and exposure to 100 degrees C for 20 min completely abolished activity. Inhibitory activity was considerably reduced by exposure to a pH of either 3 or 11. Treatment of producer cells with curing agents did not induce a high frequency of non-bacteriocinogenic cells. The odontolyticin was adsorbed by susceptible, as well as resistant, bacteria.

Actinomyces↗
PubMed1984

Growth of oral Streptococcus species and Actinomyces viscosus in human saliva.

Microorganisms in dental plaque live in constant association with saliva. The role of saliva in the adherence of bacteria to the teeth and the antibacterial properties of saliva have been well investigated; less interest has been shown in the possible role of saliva as a substrate for oral microorganisms. In this study it was shown that saliva can serve as a growth medium for oral Streptococcus spp. and Actinomyces viscosus. The cell production of these organisms on saliva was carbohydrate limited. The doubling times for growth on glucose-supplemented saliva (4 to 5 mmol/liter) ranged from 1.6 to 4.0 h. The availability of carbohydrate sources for the oral microflora is discussed in relation to microbial growth in the oral cavity.

Actinomyces↗
PubMed1987

Membrane ATPases and acid tolerance of Actinomyces viscosus and Lactobacillus casei.

Lactobacillus casei ATCC 4646 and Actinomyces viscosus OMZ105E were found to differ markedly in acid tolerance. For example, pH profiles for glycolysis of intact cells in dense suspensions indicated that glycolysis by L. casei had an optimal pH of about 6.0 and that glucose degradation was reduced by 50% at a pH of 4.2. Comparable values for A. viscosus cells were at pHs of about 7.0 and 5.6. The difference in acid tolerance appeared to depend mainly on membrane physiology, and the addition of 40 microM gramicidin to cell suspensions increased the sensitivity of the glycolytic system by as much as 1.5 pH units for L. casei and up to 0.5 pH unit for A. viscosus. L. casei cells were inherently somewhat more resistant to severe acid damage than were A. viscosus cells, in that Mg release from L. casei cells in medium with a pH of 3.0 occurred only after a lag of some 4 h, compared with rapid release from A. viscosus cells. However, the major differences pertinent to the physiology of the organisms appeared to be related to proton-translocating ATPases. Isolated membranes of L. casei had about 3.29 U of ATPase per mg of protein, compared with only about 0.06 U per mg of protein for those of A. viscosus. Moreover, the ATPase of L. casei had a pH optimum for hydrolytic activity of about 5, compared with an optimal pH of about 7 for that of A. viscosus.(ABSTRACT TRUNCATED AT 250 WORDS)

Actinomyces↗
PubMed2003

Effect of the environment on genotypic diversity of Actinomyces naeslundii and Streptococcus oralis in the oral biofilm.

The genotypic diversity of Actinomyces naeslundii genospecies 2 (424 isolates) and Streptococcus oralis (446 isolates) strains isolated from two sound approximal sites in all subjects who were either caries active (seven subjects) or caries free (seven subjects) was investigated by using the repetitive extragenic palindromic PCR. The plaque from the caries-active subjects harbored significantly greater proportions of mutans streptococci and lactobacilli and a smaller proportion of A. naeslundii organisms than the plaque sampled from the caries-free subjects. These data confirmed that the sites of the two groups of subjects were subjected to different environmental stresses, probably determined by the prevailing or fluctuating acidic pH values. We tested the hypothesis that the microfloras of the sites subjected to greater stresses (the plaque samples from the caries-active subjects) would exhibit reduced genotypic diversity since the sites would be less favorable. We found that the diversity of A. naeslundii strains did not change (chi2 = 0.68; P = 0.41) although the proportional representation of A. naeslundii was significantly reduced (P < 0.05). Conversely, the diversity of the S. oralis strains increased (chi2 = 11.71; P = 0.0006) and the proportional representation of S. oralis did not change. We propose that under these environmental conditions the diversity and number of niches within the oral biofilm that could be exploited by S. oralis increased, resulting in the increased genotypic diversity of this species. Apparently, A. naeslundii was not able to exploit the new niches since the prevailing conditions within the niches may have been deleterious and not supportive of its proliferation. These results suggest that environmental stress may modify a biofilm such that the diversity of the niches is increased and that these niches may be successfully exploited by some, but not necessarily all, members of the microbial community.

Actinomyces↗
PubMed1969

Identification of human strains of Actinomyces viscosus.

Catalase-positive actinomycetes which closely resemble the "hamster organism" described by Howell have been isolated from dental calculus and other human sources. These cultures could not be distinguished from the hamster strains on the basis of morphology, oxygen requirements, biochemical reactions, or cell wall composition. These human isolates have been classified with the hamster strains as Actinomyces viscosus. The strains from hamster and human sources fell into two serotypes. Serotype 1 contains the hamster strains plus one strain of unknown origin, whereas serotype 2 contains all of the human strains.

Actinomyces↗
PubMed1969

Actinomyces naeslundii as an agent of human actinomycosis.

The repeated isolation of Actinomyces naeslundii from clinical materials associated with disease led to a comparison of isolates from the normal mouth with isolates from pathological clinical materials not from the mouth area. No important differences were observed between the isolates from these two sources. A human case of empyema of the gall bladder, apparently due to A. naeslundii, is described.

Actinomyces↗