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PubMed1983

Antibodies of patients with Lyme disease to components of the Ixodes dammini spirochete.

Lyme disease is an inflammatory disorder of skin, joints, nervous system, and heart. The disease is associated with a preceding tick bite and is ameliorated by penicillin treatment. A spirochete (IDS) isolated from Ixodes dammini ticks has been implicated as the etiologic agent of Lyme disease. We examined the antibody responses of Lyme disease patients to IDS lysate components in order to further understand the pathogenesis of this disease. The components were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose, reacted with patients' sera, and the bound IgG was detected with 125I-labeled protein A (western blot). We found that (a) Lyme disease patients had antibodies to IDS components (b) most patients studied had antibodies to two components with apparent subunit molecular weights of 41,000 and 60,000, and (c) the patients' antibody responses during illness and remission were specific, for the most part, for the IDS. In contrast to the findings with Lyme disease sera, sera from controls showed little reactivity with IDS components in either the western blots or a derivative solid-phase radioimmunoassay.

Animals↗
PubMed2004

OspC facilitates Borrelia burgdorferi invasion of Ixodes scapularis salivary glands.

Outer surface protein C (OspC) is a differentially expressed major surface lipoprotein of Borrelia burgdorferi. ospC is swiftly upregulated when spirochetes leave the Ixodes scapularis tick gut, migrate to the salivary gland, and exit the arthropod vector. Here we show that OspC strongly binds to the tick salivary gland, suggesting a role for OspC in spirochete adherence to this tissue. In vivo studies using a murine model of Lyme borreliosis showed that while OspC F(ab)(2) fragments did not influence either the viability of spirochetes or ospC gene expression, they did interfere with B. burgdorferi invasion of tick salivary glands. We then generated ospC knockout spirochetes in an infectious clone of B. burgdorferi and examined them within the vector. OspC-deficient or wild-type spirochetes persisted equally within the gut of unfed ticks and multiplied during the tick engorgement; however, unlike wild-type B. burgdorferi, the mutants were unable to invade salivary glands. Salivary gland colonization of OspC-deficient spirochetes was completely restored when this mutant was complemented in trans with a plasmid harboring the wild-type ospC gene. These studies conclusively demonstrate the importance of OspC in the invasion of tick salivary glands by B. burgdorferi, a critical step in the transmission of spirochetes from the arthropod vector to the mammalian host.

Actins↗
PubMed1998

A new animal model for studying Lyme disease spirochetes in a mammalian host-adapted state.

There is now substantial evidence that Borrelia burgdorferi, the Lyme disease spirochete, undergoes major alterations in antigenic composition as it cycles between its arthropod and mammalian hosts. In this report, we cultivated B. burgdorferi 297 within dialysis membrane chambers implanted into the peritoneal cavities of rats to induce antigenic changes similar to those which occur during mammalian infection. Chamber-grown spirochetes, which remained fully virulent, did not express either outer surface protein A or Lp6.6, lipoproteins known to be downregulated after mammalian infection. However, they did, express p21, a well characterized outer surface protein E homologue, which is selectively expressed during infection. SDS-PAGE, two-dimensional gel electrophoresis, and immunoblot analysis revealed that chamber-grown borreliae also expressed uncharacterized proteins not expressed by in vitro-cultivated spirochetes; reactivity with sera from mice chronically infected with B. burgdorferi 297 confirmed that many of these novel proteins are selectively expressed during experimental murine infection. Finally, we used differential display RT-PCR to identify transcripts of other differentially expressed B. burgdorferi genes. One gene (2.9-7lpB) identified with this technique belongs to a family of genes located on homologous 32- and 18-kb circular plasmids. The lipoprotein encoded by 2.9-7lpB was shown to be selectively expressed by chamber-grown spirochetes and by spirochetes during experimental infection. Cultivation of B. burgdorferi in rat peritoneal implants represents a novel system for studying Lyme disease spirochetes in a mammalian host-adapted state.

Animals↗
PubMed1984

Effect of splint placement on black-pigmented Bacteroides and spirochetes in the dental plaque of beagle dogs.

The gingival microbiota in beagle dogs was investigated during a period of 42 days after the placement of continuous wire and arch bar splints. The splints were found to induce an increase in helicoidal-shaped micro-organisms and black-pigmented Bacteroides. Two different asaccharolytic Bacteroides types were isolated and tentatively identified as B. gingivalis and B. asaccharolyticus. In addition, B. intermedius-like organisms were isolated. The last two species were observed only after splint placement. The local accumulation of helicoidal-shaped micro-organisms in the epithelial tissue rather than in the micro-ulcerations was regarded as an indication of an active role for these spirochetes in the disease process. The observed shift toward tissue-invading and potentially pathogenic micro-organisms after splinting stresses the need for antimicrobial measures during splint placement in order to minimize periodontal destruction.

Animals↗
PubMed1987

Bacteriology of human gingivitis.

The subgingival bacterial floras of naturally occurring gingivitis in adults and children were characterized and compared with the floras of other periodontal conditions previously studied. The composition of the gingivitis floras was found to be distinct from that of floras associated with health or with moderate, severe, or juvenile periodontitis. There were no major differences between the floras of naturally-occurring gingivitis and the floras of the human experimental gingivitis model. Data indicated that the flora of healthy sites within a mouth is influenced by the number of inflamed sites, which argues against independence of sites bacteriologically. Proportions of ten bacterial species increased in both gingivitis and periodontitis, as compared with health, in both adults and children. These species were found in both affected and unaffected sites of people with gingivitis. The numbers of five other cultivable species and the "large treponeme", which was not cultivated, increased in gingivitis and periodontitis of adults only. Significant differences in non-spirochetal floras between children and adults were not found, although they were in the experimental gingivitis model studied previously. Cultivable spirochetes did differ between children and adults. Children had fewer samples positive for spirochetes, and children's positive samples contained greater proportions of T. socranskii subsp. paredis. Some species that predominate in periodontitis, but which are absent from healthy gingivae, were found as a small percentage of the flora in gingivitis. This suggests that increased serum and blood in the gingival crevice encourage species that relate to periodontitis.

Adult↗
PubMed1987

Early microbial colonization of permucosal implants in edentulous patients.

In edentulous patients, the microbial colonization of permucosal implants of sintered hydroxyapatite was studied. Samples were taken from mucosa and dentures before insertion of implants and from supra- and subgingival sites two to 10 weeks after insertion. In total, five patients and 10 implants with clinically healthy peri-implant tissues were studied. The samples were investigated by dark-field microscopy and anaerobic culture. The supragingival plaque of the implants was dominated by Gram-positive cocci and rods, the subgingival plaque by Haemophilus spp. and Veillonella parvula. A group of bacteria was found specifically related to the implants: Actinomyces odontolyticus, Peptostreptococcus micros, Haemophilus actinomycetemcomitans, Eikenella corrodens, Capnocytophaga sputigena, and Leptotrichia buccalis. Black-pigmented Bacteroides was not found in any of the examined samples. Spirochetes were observed in denture plaque samples and in supragingival plaque of the implants. It is concluded that bacteria known as potential periodontal pathogens colonize the permucosal implants in the first weeks after insertion. The presence of these species seems to be dependent on the ecological factors provided by the artificial gingival crevice of the permucosal implants in the edentulous mouth.

Actinomyces↗
PubMed1987

Characteristics of trypsin-like activity in subgingival plaque samples.

Previous studies have demonstrated that the hydrolysis of the trypsin substrate N-benzoyl-DL-arginine-2-naphthylamide (BANA), by subgingival plaque obtained from a single site, correlates best with the numbers and proportions of spirochetes in plaque samples and may serve as an indicator of clinical disease. In this investigation, we determined whether the association between BANA hydrolysis and spirochetes could be obtained in pooled subgingival plaque samples. Concomitantly, the characteristics of this reaction in terms of substrate type and concentration, microbial numbers needed to give a positive reaction as assessed by microscopic counts, rapidity of hydrolysis, and the effect of pH and various additives on the plaque BANA hydrolytic activity have been studied in pooled plaque samples from patients who were periodontally healthy or diseased. In addition, it was determined whether BANA hydrolytic activity found in subgingival plaque reflected contributions from saliva and supragingival plaque. Results indicated that the assay can best be performed with 0.67 mmol/L BANA at pH 7.0. EDTA and CaCl2 gave a slight inhibition and DTT a slight enhancement of the BANA reaction by the pooled plaque suspensions. The majority of the reactions (85%) developed their full color after overnight incubation. BANA hydrolysis was not found in saliva and occurred with much greater frequency in subgingival plaque as opposed to supragingival plaque. Analysis of the data indicated that BANA hydrolysis by pooled subgingival plaque samples is a suitable test for the detection of spirochetes when two or three spirochetes per high microscopic field are present in the sample.

Analysis of Variance↗
PubMed1988

Correlation of the hydrolysis of benzoyl-arginine naphthylamide (BANA) by plaque with clinical parameters and subgingival levels of spirochetes in periodontal patients.

Recent studies have shown that the extent of hydrolysis by plaque of the trypsin substrate, N-benzoyl-DL-arginine-2-naphthylamide (BANA), correlates with the numbers and proportions of spirochetes in subgingival plaque samples, and appears to be an indicator of clinical disease. In this study, BANA hydrolysis by subgingival plaque was evaluated in a blind manner for its ability to reflect both clinical parameters and subgingival levels of bacteria and spirochetes. Subgingival plaque samples were collected from periodontally healthy and diseased sites in 23 untreated periodontal patients and in 13 treated and maintained periodontal patients. In untreated patients, BANA hydrolysis was statistically associated with the total number of spirochetes and bacteria in the plaque sample, but in the treated patients BANA hydrolysis was statistically associated only with the spirochetes. Most BANA-positive reactions in both patient groups were from the sites which were clinically diseased and high in spirochetes. The majority of the negative reactions for BANA hydrolysis in both patient groups was among the sites which were periodontally healthy and low in spirochetes. Specificity and sensitivity of the test were above 80% for disease status in untreated patients. The predictive value of a positive and negative test was above 83%. Slightly lower sensitivity, specificity, and predictive values were found in the treated group. The BANA reaction appears to be an accurate and simple indicator of both clinical disease status and plaque levels of spirochetes in individual tooth sites in untreated and treated periodontal patients.

Arginine↗
PubMed1992

The influence of denture-wearing and age on the oral microflora.

The effects of denture-wearing and age on the prevalence of selected bacteria of dental significance and on the carriage of opportunistic pathogens in molar plaque and whole saliva were determined in 120 healthy subjects, 41 of whom wore partial dentures. The subjects were divided into four age groups: 20-39 years (group A), 40-59 years (group B), 60-79 years (group C), and greater than or equal to 80 years (group D). The proportions, mean log10 viable counts, and isolation frequency of yeasts and lactobacilli in saliva and plaque were consistently higher in partial-denture wearers. The proportions of staphylococci and mutans streptococci were also raised in denture wearers, but these differences did not reach statistical significance. When the data were analyzed for age effects, both yeasts and lactobacilli were found to be increased in saliva with age, but statistically significant differences were generally found only between denture wearers in group D and subjects in the control group A. The isolation frequency of yeasts from plaque was also significantly higher in denture wearers of the oldest age group (D) compared with those in group A. A. viscosus predominated over A. naeslundii in the older age groups, regardless of the presence of dentures. Enterobacteria were isolated occasionally but only from the saliva of denture wearers in group D. Spirochetes and black-pigmented anaerobes were generally found in lower numbers in denture wearers. Collectively, the data show that components of the oral microflora in adults can be independently influenced by both age and the wearing of partial dentures.

Actinomyces↗
PubMed1995

Full- vs. partial-mouth disinfection in the treatment of periodontal infections: short-term clinical and microbiological observations.

In a standard periodontal treatment strategy with consecutive root planings (per quadrant at a one- to two-week interval), re-infection of a disinfected area might occur before completion of the treatment. This study examines, both clinically and microbiologically, whether a full-mouth disinfection within 24 hours significantly improves the outcome of periodontal treatment. Ten patients with advanced chronic periodontitis were randomly allocated to a test and a control group. The patients from the control group received scalings and root planings as well as oral hygiene instructions per quadrant at two-week intervals. Full-mouth disinfection in the test group was sought by the removal of all plaque and calculus (in two visits within 24 hours). In addition, at each of these visits, the tongue was brushed with a 1% chlorhexidine gel for one min and the mouth rinsed with a 0.2% chlorhexidine solution for two min. Furthermore, subgingival chlorhexidine (1%) irrigation was performed in all pockets. The recolonization of the pockets was retarded by oral hygiene and 0.2% chlorhexidine rinses during two weeks. The clinical parameters were recorded, and plaque samples were taken from the right upper quadrant at baseline and after one and two months. The test group patients showed a significantly higher reduction in probing depth for deep pockets at both follow-up visits (p < 0.05). At the one-month visit, differential phase-contrast microscopy revealed significantly lower proportions of spirochetes and motile rods in the test group (p = 0.01). Culturing showed that the test group harbored significantly fewer pathogenic organisms at one month (p = 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1975

The etiology of swine dysentery. III. The role of selected gram-negative obligate anaerobes.

A disease resembling swinee dysentery occurred in gnotobiotic piglets previously colonized with Escherichia coli and given a mixture of five enteric anaerobes and spirochete B-78, orally. No disease occurred in germ-free piglets exposed to four Gram-negative obligate anaerobes or to the spirochete; however, if the four respective anaerobes were introduced into gnotobiotic pigs previously colonized with the spirochete, or when the spirochete was introduced into gnotobiotic pigs colonized with the anaerobes, a disease occurred that simulated swin dysentery. Swine dysentery is probably caused by the specific interaction of one or more enteric Gram-negative obligate anaerobes and a spirochete.

Animals↗
PubMed1995

Susceptibility of porcine ileal enterocytes to the cytotoxin of Serpulina hyodysenteriae and the resolution of the epithelial lesions: an electron microscopic study.

The cytotoxin from Serpulina hyodysenteriae was injected into ileal loops of eight germ-free pigs, and the effects on the villi were observed after 1, 3, and 18 hours of exposure. The mature vacuolated villus enterocytes of the proximal part of the absorptive villi were most susceptible to the lethal effects of the cytotoxin and were extensively exfoliated. The enterocytes at the base of the villi, the goblet cells, and the follicle-associated epithelium of the dome villi, particularly the M cells, were less affected. As the enterocytes were shed, the villi progressively shortened and the basement membrane became extensively folded. The absorptive villi were markedly stunted at 3 hours, and flattened globlet cells predominated at the site of restitution of the lesion. The myofibroblasts were also damaged, apparently subsequent to the exfoliation of the enterocytes. There was no further damage at 18 hours. The absorptive villi were stunted and were devoid of the large interstitial spaces of the normal lamina propria; the enterocytes were generally columnar, and at the apex of each villus there was an accumulation of goblet cells. There was a preponderance of M cells at the apices of the dome villi. Restitution of the lesions was not as rapid as observed in in vitro systems. The changes observed indicated that as the proximal enterocytes of the absorptive villi were shed, the loss of hydrostatic forces in the lamina propria allowed the myofibroblasts to collapse the villi by progressively retracting the basement membrane. This reduced the surface area to be covered during restitution. Resolution of the lesions was still incomplete after 18 hours.

Animals↗
PubMed1996

Light microscopic and ultrastructural changes in the ceca of chicks inoculated with human and canine Serpulina pilosicoli.

Light microscopic and ultrastructural changes were observed in chicks challenged with North American Serpulina pilosicoli, a weakly beta-hemolytic intestinal spirochete (WBHIS) associated with human and canine intestinal spirochetosis. Chicks in control groups received trypticase soy broth or canine Serpulina innocens. The birds were necropsied at weekly intervals, and the ceca were processed for bacteriologic and pathologic examinations. No WBHIS were isolated from the ceca of chicks in the control groups, but WBHIS with genotypes similar to the parent isolates were isolated from the ceca of chicks inoculated with human and canine S. pilosicoli. Gross examination revealed no significant changes in the ceca of chicks at any time post-inoculation. Light microscopic examination revealed no spirochetal attachment in the ceca of chicks in control groups. In contrast, focal to diffuse thickening of the brush border of the surface epithelium along with dilation of the crypt lumina and mild focal lamina propria heterophil infiltration were present in the ceca of chicks inoculated with human and canine S. pilosicoli. Scanning electron microscopic examination revealed focal to confluent spirochetal attachment mainly in the furrow region at the periphery of the crypt units. Transmission electron microscopic examination revealed spirochetes attached to the brush border of the cecal epithelium, causing effacement of the microvilli and disruption of the terminal web microfilaments. The cecal epithelium of chicks inoculated with the canine S. pilosicoli also had caplike elevations of the apical membrane at the point of attachment of the spirochetes together with large numbers of vesicles in the cytoplasm immediately beneath the terminal web and evidence of spirochetal invasion beyond the mucosal barrier. The changes observed suggested that the mechanism of attachment of human and canine S. pilosicoli to the cecal epithelium of chicks was analogous to but different from that described previously for other attaching and effacing gastroenteric bacterical pathogens of human beings and animals.

Animals↗