| 1. |
- Collins, A R, et al.
(författare)
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Cystatin D, a natural salivary cysteine protease inhibitor, inhibits coronavirus replication at its physiologic concentration
- 1998
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Ingår i: Oral Microbiology and Immunology. - : Wiley. - 0902-0055 .- 1399-302X. ; 13:1, s. 59-61
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Tidskriftsartikel (refereegranskat)abstract
- This study was conducted to examine the effect of cystatin D, a newly discovered salivary cysteine protease inhibitor, on human coronavirus replication. When MRC-5, human diploid lung cells, were incubated with dilutions of recombinant human cystatin D from 0.65-10 microM for 1 h prior to, during and after infection with coronavirus OC43 and 229e strains, a decrease in virus yield was observed resulting in an IC50 of 0.8 microM for both virus strains. This dose is within the normal concentration range of cystatin D, 0.12-1.9 microM found in saliva. When a single dose, 2.5 microM, was applied, cystatin inhibition of release of virus progeny was not overcome until three days post infection whereas inhibition by leupeptin, a serine and cysteine protease inhibitor, was completely abrogated by two days. When cellular toxicity was measured by 3H-thymidine uptake, cystatin D did not markedly affect cell proliferation below a 10 microM dose. The results demonstrate that cystatin D is a potent inhibitor of coronavirus replication.
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| 2. |
- Wallengren, Marie Louise, et al.
(författare)
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Low salivary IgA activity to cell-surface antigens of mutans streptococci related to HLA-DRB1*04
- 2005
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Ingår i: Oral Microbiology and Immunology. - : Blackwell Munksgaard. - 0902-0055 .- 1399-302X. ; 20:2, s. 73-81
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Tidskriftsartikel (refereegranskat)abstract
- Background/aims: Mutans streptococci are found in almost all individuals, though there are large differences in colonization levels between individuals. These differences are not readily explained, though several factors are believed to influence the colonization. One factor is the immune response to mutans streptococci, mainly provided by salivary immunoglobulin A (IgA). In a previous study, differences in salivary IgA reactions to oral streptococci were observed between human leukocyte antigen (HLA)-DR4-positive and DR4-negative individuals. A lower salivary IgA activity to Streptococcus mutans in particular was most pronounced for two DR4 subgroups, DRB1*0401 and *0404. The main purpose of this study was to further investigate, in a larger study group, the salivary IgA activity to antigens of three oral streptococci in relation to different HLA-DRB1*04 alleles. Methods: Stimulated saliva was collected from 58 HLA-DRB1*04-positive individuals. Whole cell antigen extracts from S. mutans, Streptococcus sobrinus and Streptococcus parasanguis and the streptococcal antigen (SA) I/II were separated in SDS-PAGE, transblotted and detected with diluted saliva (Western blot), and analyzed in a computer program. All distinct immunoblot bands over 100 kDa were recorded and compared in relation to DRB1*04. Results: The immunoblots revealed lower salivary IgA reactions to S. mutans, S. sobrinus and SA I/II, but not to S. parasanguis, for the DRB1*0401- and *0404-positive individuals compared to other DRB1*04 types. For the *0401 subgroup there was a significant association with a lower IgA response to S. mutans. Conclusion: The results confirm earlier observations and may also support previous demonstrated association between colonization by mutans streptococci and the serologically defined HLA-DR4.
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| 3. |
- Fujise, O, et al.
(författare)
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Clonal distribution of natural competence in Actinobacillus actinomycetemcomitans.
- 2004
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Ingår i: Oral Microbiology and Immunology. - : Wiley. - 0902-0055 .- 1399-302X. ; 19:5, s. 340-342
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Tidskriftsartikel (refereegranskat)abstract
- The competence for natural transformation was investigated in 67 Actinobacillus actinomycetemcomitans strains. The transformation assays were performed with both cloned DNA fragments and chromosomal markers of A. actinomycetemcomitans. Competence was found in 12 of 18 serotype a strains, 0 of 21 serotype b strains, 0 of 14 serotype c strains, 3 of 6 serotype d strains, 3 of 4 serotype e strains, 0 of 3 serotype f strains, and 0 of 1 nonserotypeable strain. The transformation frequencies varied from 5 x 10(-3) to 4 x 10(-6) (median 1.5 x 10(-4)). The distribution pattern of natural competence is concordant with the major clonal lineages of A. actinomycetemcomitans. Serotype a strains are predominantly competent for transformation, while serotypes b and c strains are apparently non-competent.
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| 4. |
- Hedberg, Maria, et al.
(författare)
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Sugar fermentation in probiotic bacteria : an in vitro study
- 2008
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Ingår i: Oral Microbiology and Immunology. - 0902-0055 .- 1399-302X. ; 23:6, s. 482-485
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Food supplemented with probiotic bacteria is a rapidly growing sector of the market. The aim of the present study was to evaluate and compare the acid production of selected probiotic strains available in commercial products.METHODS: Six Lactobacillus strains (Lactobacillus plantarum 299v and 931; Lactobacillus rhamnosus GG and LB21; Lactobacillus paracasei subsp. paracasei F19, and Lactobacillus reuteri PTA 5289) were cultivated at 37 degrees C in an anaerobic atmosphere on Man, Rogosa, Shape (MRS) agar for 48 h or MRS broth for 16 h. After centrifugation, the cells were washed and resuspended in sterile phosphate-buffered saline and immediately subjected to a fermentation assay with 12 different carbohydrates (nine sugars and three sugar alcohols) in microtiter plates with a pH indicator. The plates were examined for color changes after 24, 48, and 72 h of incubation under aerobic and anaerobic conditions. Three scores were used: negative (pH > 6.8); weak (pH 5.2-6.8), and positive (pH < 5.2). The strains were characterized with the API 50 CH system to confirm their identity.RESULTS: L. plantarum fermented all the sugars except for melibiose, raffinose, and xylitol. Both L. rhamnosus strains were generally less active although L. rhamnosus GG was slightly more active than strain LB21 in the 5% CO(2) setting. The latter strain exhibited negative reactions for sucrose, maltose, arabinose, and sorbitol under anaerobic conditions. The assays with L. paracasei and L. reuteri had negative or weak reactions for all tested sugars under both aerobic and anaerobic conditions.CONCLUSION: The metabolic capacity to form acid from dietary sugars differed significantly between the various probiotic strains.
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| 5. |
- Katsoulis, J, et al.
(författare)
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Impact of sample storage on detection of periodontal bacteria.
- 2005
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Ingår i: Oral Microbiology and Immunology. - 0902-0055 .- 1399-302X. ; 20:2, s. 128-130
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND/AIMS: Information on the impact of sample storage prior to analysis by DNA methods is limited. The aim of this study was to investigate the effect of subgingival sample storage on bacterial detection and enumeration.MATERIAL AND METHODS: Subgingival plaque samples were studied by a) checkerboard DNA-DNA hybridization by immediate processing, b) storage at + 4 degrees C for 6 weeks, c) storage at - 20 degrees C for 6 months or d) storage at - 20 degrees C for 12 months.RESULTS: No differences in total DNA were found between protocol 1 and 2, or between protocol 3 and 4. Protocol 1 yielded 2.4 times more total bacterial DNA than did protocol 3 (P < 0.001). Actinobacillus actinomycetemcomitans and Campylobacter gracilis were detected in 21.1% of the immediately processed samples but only in 6.6% of the samples after 12 months of storage. Similar changes were noticed for Treponema denticola, which was detected in 22.3% and 9.2%, respectively. Streptococci spp., Fusobacterium nucleatum and Tannerella forsythia did not seem to be affected by storage. In contrast, the level of Campylobacter rectus detection frequency changed from 2.6% if processed immediately to 15.8% if samples were stored for 12 months.CONCLUSIONS: In longitudinal clinical studies including microbiological samples and processed with DNA-DNA hybridization methods, samples should be stored for the same period of time before processing to avoid loss of microbiological information.
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| 6. |
- Lundin Wallengren, Marie Louise, et al.
(författare)
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Salivary IgA reactions to cell-surface antigens of oral streptococci.
- 2004
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Ingår i: Oral Microbiology and Immunology. - : Blackwell Munksgaard. - 0902-0055 .- 1399-302X. ; 19:3, s. 188-195
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: In the immunoblot technique, using whole bacteria cell extracts as antigens, both intra- and extracellular antigens are de-tected, which gives a large number of immunoglobulin A (IgA) reac-tions (immunoblot bands) when incubated with saliva. It is important to distinguish which immunoblot bands represent bacterial cell-surface antigens, since these antigens could be involved in adhesion mecha-nisms and be available for blocking in vivo. METHODS: Bacterial ex-tracts of Streptococcus mutans, Streptococcus sobrinus, Streptococcus parasanguis and the streptococcal antigen I/II were separated using SDS-PAGE. The antigens were detected with saliva in Western blot. Untreated saliva and saliva in which cell-surface reactive IgA had been absorbed with whole bacteria cells were analyzed. RESULTS: Ap-proximately half the number of the bands were absent for saliva ab-sorbed with homologous cells, compared to untreated saliva. The ab-sorption pattern was almost identical for S. mutans and S. sobrinus but not for S. parasanguis. Salivary IgA reactive against streptococcal antigen I/II was absorbed by S. mutans cells, to a lesser extent by S. sobrinus cells, and not at all by S. parasanguis cells. CONCLUSION: It is likely that the bands that were absent after absorption represented cell-surface antigens. For S. mutans and S. sobrinus, these bands were probably the streptococcal antigen I/II. Copyright Blackwell Munks-gaard, 2004.
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| 7. |
- Page, R C, et al.
(författare)
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Immunization of Macaca fascicularis against experimental periodontitis using a vaccine containing cysteine proteases purified from Porphyromonas gingivalis.
- 2007
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Ingår i: Oral Microbiology and Immunology. - 0902-0055 .- 1399-302X. ; 22:3, s. 162-8
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Periodontitis is a common infectious disease to which Porphyromonas gingivalis has been closely linked, in which the attachment tissues of the teeth and their alveolar bone housing are destroyed. We conducted a study to determine if immunization using a purified antigen could alter the onset and progression of the disease.METHODS: Using the ligature-induced model of periodontitis in Macaca fascicularis, we immunized five animals with cysteine protease purified from P. gingivalis and used an additional five animals as controls. Alveolar bone loss was measured by digital subtraction radiography.RESULTS: Immunization induced high titers of specific immunoglobuin G serum antibodies that were opsonic. Total bacterial load, levels of P. gingivalis in subgingival plaque and levels of prostaglandin E(2) in gingival crevicular fluid were significantly reduced. Onset and progression of alveolar bone loss was inhibited by approximately 50%. No manifestations of toxicity were observed.CONCLUSIONS: Immunization using a purified protein antigen from P. gingivalis inhibits alveolar bone destruction in a ligature-induced periodontitis model in M. fascicularis.
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| 8. |
- Wallengren, Marie Louise, et al.
(författare)
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HLA-DR4 and salivary immunoglobulin A reactions to oral streptococci
- 2001
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Ingår i: Oral Microbiology and Immunology. - : Wiley. - 0902-0055 .- 1399-302X. ; 16:1, s. 45-53
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to describe and compare salivary immunoglobulin A (IgA) antibody reactions to extracts of strains of three oral streptococci in human leukocyte antigen (HLA)-DR4-positive and -DR4-negative subjects. Whole paraffin-stimulated saliva samples were collected from 27 apparently healthy subjects. Previous HLA typing showed that 20 subjects were DR4 positive and 7 were DR4 negative. HLA-DRB1*04 subtyping was performed among the DR4-positive subjects. Whole-cell antigen extracts from Streptococcus mutans (KPSK 2), Streptococcus sobrinus (OMZ 65) and Streptococcus parasanguis (Nt 62) were separated in SDS-PAGE. The antigens were immunoblotted with diluted saliva (Western blot), scanned and analyzed in a computer system. All immunoblot bands were recorded in DR4-positive and DR4-negative saliva pools, and bands with an optical density >or=0.1 were selected for analysis in individual salivas. The DR4-negative subjects in general had more immunoblot bands and more distinct bands than did the DR4-positive subjects. A higher concentration of total IgA in saliva was correlated with more bands, especially to antigens separated from S. mutans. When the number of bands was calculated per IgA unit, significant differences were observed between DR4-positive and DR4-negative salivas. This was particularly seen for S. mutans and S. parasanguis. As the number of bands was analyzed in relation to DR4 subgroups, DRB1*04, there was a lower salivary IgA activity to S. mutans in the DRB1*0401 and *0404. The variable level of correlation previously demonstrated for S. mutans colonisation and serologically defined DR4 positive subjects might be explained by the heterogeneity in this group, and the relation should be sought on a subgroup level.
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| 9. |
- Wallengren, Marie Louise, et al.
(författare)
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Human leukocyte antigens in relation to colonization by mutans streptococci in the oral cavity
- 1991
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Ingår i: Oral Microbiology and Immunology. - : Wiley. - 0902-0055 .- 1399-302X. ; 6:5, s. 292-4
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Tidskriftsartikel (refereegranskat)abstract
- Mutans streptococci are well established as caries-inducing microorganisms in man. Most humans carry the bacteria, but in highly different numbers. This cannot be explained by environmental factors only. The aim of this study was to investigate a possible association between levels of colonization by mutans streptococci and the presence of certain B and DR human leukocyte antigens (HLA). Altogether, 170 subjects who had their HLA antigens determined (76 renal transplant patients and 94 healthy blood donors) were selected for the investigation. Paraffin-stimulated saliva samples were taken using the wooden spatula method with subsequent cultivation of mutans streptococci on mitis salivarius bacitracin agar plates. An association between the absence of HLA-DR 4 antigens and low, or undetectable, levels of mutans streptococci was found. This was statistically significant for the immunosuppressed renal transplant subjects. The same trend was observed among the healthy blood donors.
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| 10. |
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