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PubMed1995

Serpulina hyodysenteriae challenge of fattening pigs vaccinated with anadjuvanted bivalent bacterin against swine dysentery.

An experimental fattening period was performed with 36 pigs in order to evaluate the safety and efficacy of a bivalent adjuvanted Serpulina hyodysenteriae bacterin. The pigs originated from three different farms and were split into six groups. Eighteen pigs were vaccinated twice, two weeks apart and the rest served as controls. One unvaccinated pig in each group was inoculated intragastrically with 4 x 10(8) active S. hyodysenteriae spirochaetes, B 78 strain. Weight evolution, clinical symptoms, shedding of S. hyodysenteriae and serum antibody titres were monitored for 12 weeks in all pigs. The severity of clinical symptoms and shedding of spirochaetes in faeces were significantly reduced in vaccinated pigs as compared to controls. Statistically significant differences in weight gain between vaccinates and controls were detected coinciding with the maximum shedding of S. hyodysenteriae in faeces. All vaccinated pigs seroconverted, as measured by indirect ELISA, and had a good anamnestic response after the second vaccine dose. The bacterin proved to be useful for both the reduction of clinical symptoms and the number of infected animals in a fattening unit. Adverse post-vaccinal reactions were not observed in any pig.

Animals↗
PubMed1994

Effect of gingival fluid collection on subgingival plaque sampling.

The purpose of this study was to determine whether gingival crevicular fluid (GCF) sampling by paper strip removes sufficient bacteria to affect subsequent subgingival plaque sampling using a curette. In 25 subjects, one healthy, gingivitis and periodontitis site was sampled for GCF using a strip followed by subgingival plaque sampling with a curette. Bacterial assays indicated that GCF strips removed significant numbers of bacteria when placed intracrevicularly for 5 s. A greater proportion of total bacteria was removed with strip sampling at healthy rather than gingivitis or periodontitis sites. Qualitative assessment of presence or absence of spirochaetes and dark-pigmented species indicated potential for significant interference of curette sampling by the strip at gingivitis and healthy sites. We concluded that paper strip GCF sampling may significantly affect curette sampling at the same sites. The magnitude of this impact depended on the clinical classification of specific sites and the assay performed.

Bacteria↗
PubMed1975

Possible formation and development of spirochaete attachment sites found on the surface of symbiotic polymastigote flagellates of the termite Reticulitermes flavipes.

We propose that spirochaete attachment sites arise from peripheral protrusions which appear on the surface of polymastigote flagellates. These protrusions develop into bracket-shaped structures which then form the mature attachment site. Next the site becomes detached from the surface of the cell; this latter process may be facilitated by the fusion of vesicles located in the region immediately beneath the spirochaete attachment site. This theory could explain the variability in the number and distribution of attachment sites on the surface of the flagellates.

Animals↗
PubMed1980

The symbiotic microbial community of the Sonoran Desert termite: Pterotermes occidentis.

Pterotermes occidentis is a large, obscure, very primitive dry wood termite limited to the Sonoran desert of North America. Its development, caste system and behavior are discussed in relation to aspects of its ecology. What appear to be single wood-digesting individual termites are in fact insect hosts which harbor extensive microbial communities estimated to contain more than 40 interacting species. All healthy, wood-eating Pterotermes contain these densely populated communities of highly motile symbionts suggesting that species diversity is necessary for termite survival. A morphological catalogue of the major hindgut microbes is presented here. From 10(7) to 10(11) bacteria and from 10(3) to 10(6) protists/ml of hindgut fluid are found in an average nymph or larva. The species of four wood-ingesting mastigotes (genera Trichonympha, Metadevescovina, Tricercomitus and Microrhopalodina) and nearly 30 morphologically distinct types of bacteria are described. The description of this morphological diversity observed with light, scanning and transmission electron microscopy is a prerequisite to functional analyses of the symbioses. Since Pterotermes is easily maintained in the laboratory and is so large it is hoped that it will provide a useful model for symbiosis research.

Animals↗
PubMed1988

Multiple sclerosis is a chronic central nervous system infection by a spirochetal agent.

Multiple Sclerosis (MS) is a chronic central nervous system (CNS) infection similar to Lyme Disease or Neurosyphilis in its latency period, pathogenesis, symptoms, histopathology and chronic CNS involvement. It does not have as yet a fully identified spirochetal etiological agent. Much research and clinical support for this hypothesis was published before 1954 and is based on silver staining of neural lesions, animal isolation of the etiologic agent and the characteristic symptoms and pathogenesis of the disease. If this hypothesis is correct, the disease should be treatable with antibacterial agents that penetrate the CNS (such as high dose antibiotics), diagnosible by specific immunological tests, and preventable by early treatment or by the use of vaccines in high risk populations.

Animals↗
PubMed1992

Characterization of Serpulina (Treponema) hyodysenteriae and related intestinal spirochetes by ribosomal RNA gene restriction patterns.

Serpulina (Treponema) hyodysenteriae strain A-1 partially purified rRNA, labelled with photobiotin, was used as a non-radioactive probe to identify the rRNA gene restriction patterns of S. hyodysenteriae strains and other spirochetes. Sau3A restriction enzyme digests resulted in similar rRNA gene restriction patterns in S. hyodysenteriae strains from five different countries. Some S. hyodysenteriae strains could be differentiated by variations in their rRNA gene restriction patterns after cleavage of DNA by restriction enzymes SspI or BglII. S. innocens and Treponema succinifaciens, non-pathogenic pig intestinal spirochetes, had rRNA gene restriction patterns that differed markedly from the S. hyodysenteriae patterns, and from each other.

Animals↗
PubMed1988

Etiological agents of bovine mastitis.

A total of 137 microbial species, subspecies and serovars have been isolated from the bovine mammary gland. Nucleic acid hybridization studies have restructured the classification of many mastitis pathogens. Availability of defined species descriptions has permitted greater insight into the distribution and pathogenicity of many previously unrecognized microorganisms associated with bovine mastitis. Precise epidemiological studies are needed to better delineate the role of some microorganisms in bovine mastitis and to aid development of improved control methods.

Animals↗
PubMed1993

Comparison of Serpulina hyodysenteriae B78, the type strain of the species, with other S. hyodysenteriae strains using enteropathogenicity studies and restriction fragment length polymorphism analysis.

The enteropathogenicity of Serpulina hyodysenteriae B78, the type strain of the species, was compared with S. hyodysenteriae B204, a known pathogenic strain, in 7 week-old pigs. Clinical signs of swine dysentery were observed in 11/18 pigs (61.1%) inoculated with S. hyodysenteriae strain B204. However, in pigs inoculated with S. hyodysenteriae B78, only 1/21 (4.8%) of the pigs became infected. The 21 pigs inoculated with strain B78 included four pigs which received 5-fold higher numbers of S. hyodysenteriae B78 cells than were normally used in test inoculations. None of the four pigs became infected. Restriction fragment length polymorphism (RFLP) analysis, using a randomly cloned piece of S. hyodysenteriae B204 genomic DNA as the probe (pSRM5), was found to be useful in distinguishing S. hyodysenteriae strains. RFLP analysis confirmed that the one S. hyodysenteriae B78-inoculated pig that exhibited clinical signs of swine dysentery was infected with S. hyodysenteriae B78, and not by contamination with S. hyodysenteriae B204. These results indicate that S. hyodysenteriae B78 is only weakly pathogenic and should not be used in experimental infections of swine or in studies of virulence determinants where use of a pathogenic strain of S. hyodysenteriae would be crucial.

Animals↗
PubMed1993

Comparison of outer-membrane fractions of Serpulina (Treponema) hyodysenteriae.

Sarkosyl-insoluble fractions (outer-membrane proteins) and endoflagella (EF) fractions of Serpulina hyodysenteriae serotypes 1-7 were examined for protein differences using SDS-PAGE. Both the outer-membrane proteins (OMP) and endoflagella were also examined for antigenicity using porcine sera from acutely infected and convalescent swine. Seven major staining proteins were resolved in outer-membrane enriched fractions ranging in molecular weight between 42 and 32 kDa. A comparison of purified EF to OMP from serotype 1 and 2 isolates of Serpulina hyodysenteriae demonstrated that six of the seven OMP were actually EF. Sera from swine with acute swine dysentery identified only a portion of the proteins from both preparations. In contrast, immune sera from convalescent swine identified all the proteins in the OMP and EF preparations as well as an additional 16 kDa carbohydrate antigen.

Animals↗
PubMed1993

Cross-reactivity between B. burgdorferi and other spirochetes affects specificity of serotests for detection of antibodies to the Lyme disease agent in dogs.

Western immunoblots, the kinetics-based enzyme-linked immunosorbent assay (KELA), and the microagglutination test were used to evaluate cross-reactivity among antibodies to serovars of Leptospira interrogans (leptospiral serovars), and B. burgdorferi from naturally infected dogs, and to Serpulina (Treponema) hyodysenteriae from vaccinated rabbits. Whole-cell lysates from Borrelia spp., leptospiral serovars, and Serpulina spp. were used for SDS-PAGE, western blots, and KELA. Crossreactivity occurred between the antibodies to B. burgdorferi and leptospiral serovars when tested on the heterologous antigens. Antibodies to leptospiral serovars tended to cross-react more strongly with antigens of B. burgdorferi spp. than did antibodies to B. burgdorferi when tested against antigens of leptospiral serovars. The antibodies against B. burgdorferi showed a lesser degree of cross-reactivity to the antigens of S. hyodysenteriae and S. innocens than they did to leptospiral serovars. We conclude that cross-reactivity occurs between B. burgdorferi and leptospiral serovars. Validation and interpretation of ELISA tests for detection of antibody activity to whole cell lysates of the Lyme agent must take this cross-reactivity into consideration. Conversely, dogs infected with the Lyme agent do not show significant cross-reactivity in the microagglutination test for antibody to the leptospiral serovars.

Agglutination Tests↗
PubMed1993

Identification and partial characterization of a group of weakly beta-hemolytic intestinal spirochetes of swine distinct from Serpulina innocens isolate B256.

Comparative analyses of a group of 16 weakly beta-hemolytic spirochetes isolated from feces and mucosal scrapings of intestines of swine in the midwestern United States, and eastern Canada revealed the existence of a phenotypically and genotypically related group of 7 isolates. Although isolates in this group differed from all known reference isolates of intestinal spirochetes of swine, partial similarity was detected with S. joneseae isolate 16, a newly identified weakly beta-hemolytic intestinal spirochete of human beings. In addition to producing weak beta-hemolysis on blood agar plates, S. innocens isolates B256 and 4/71, S. joneseae isolate 16, and the 16 field isolates lacked the characteristic ring phenomenon described for Serpulina hyodysenteriae, an enteropathogenic spirochete of swine. All but one of the field isolates of weakly beta-hemolytic intestinal spirochetes gave negative results for indole production. The same isolates yielded variable results for alpha-galactosidase production. By transmission electron microscopic examination of negatively-stained cross-sections of spirochetes, the isolates segregated into groups containing either 4 to 7 or 9 to 16 profiles of axial filaments per cell cross-section. Analyses of genomic DNA of selected isolates using whole-genome cross-hybridization revealed a single genetic type consisting of 7 field isolates of weakly beta-hemolytic intestinal spirochetes. The 7 field isolates were distinct from the reference isolates S. innocens isolates B256 and 4/71, S. hyodysenteriae isolates B78 and B204, and Treponema succinifaciens isolate 6091 based on the number of axial filaments per cell cross-section and lack of cross-hybridization signal. S. joneseae isolate 16, had the same number of axial filaments per cell cross-section and produced a weak hybridization signal with a representative isolate of the 7 weakly beta-hemolytic field isolates from swine. This report suggests the existence of a widely distributed group of closely related weakly beta-hemolytic intestinal spirochetes of swine with genotypic characteristics distinct from S. innocens isolate B256.

Animals↗
PubMed1995

Expression of the SmpA outer membrane lipoprotein of Serpulina hyodysenteriae strain P18A in vivo.

An ELISA has been developed using a monoclonal antibody (F325 AC4) to the SmpA surface lipoprotein of Serpulina hyodysenteriae strain P18A when grown in vitro. The lower level of detection of the ELISA was approximately 5 x 10(6) spirochaetes/ml when spirochaetes were either resuspended in phosphate buffered saline or in pig faeces. When pigs were challenged with S. hyodysenteriae strain P18A the lipoprotein was detected in the faeces of pigs by ELISA when the numbers of spirochaetes excreted was greater than 10(6) per g of faeces. After onset of clinical signs in the pig, expression of SmpA was not detected by ELISA or by Western blotting using either monoclonal antibody F325 AC4 or polyclonal antiserum B50 against the SmpA antigen. However, when the in vivo grown spirochaetes were subsequently cultured in vitro expression of SmpA was detected by Western blotting. In the mouse model of swine dysentery S. hyodysenteriae spirochaetes obtained from mice with gross lesions also did not express SmpA. It was concluded that the apparent lack of expression may have been the result of environmental regulation of gene expression or antigenic variation and was not due to denaturation of the antigen in vivo.

Animals↗
PubMed1994

Effect of divalent cations on hemolysin synthesis by Serpulina (Treponema) hyodysenteriae: inhibition induced by zinc and copper.

Serpulina hyodysenteriae produces an oxygen-stable heat-labile hemolysin that may be an important virulence factor in the pathogenesis of swine dysentery. We examined the effect of Ca2+, Co2+, Cu2+, Fe2+, Mg2+, Mn2+, Ni2+, and Zn2+ on the hemolytic activity of cell-free supernatant (CFS) from S. hyodysenteriae, isolate B204. Cells harvested from late logarithmic phase cultures were incubated in phosphate-buffered saline containing glucose and RNA-core (PBS-GR) with or without cations and the hemolytic activity of CFS obtained after successive 30 min incubation and washing cycles was determined. The addition of either ZnSO4 or CuSO4 to the PBS-GR caused complete inhibition of hemolytic activity after 3 cycles; other cations gave results similar to control extracts. Reduction in the concentration of Zn2+ in CFS by 60 to 80% after each incubation cycle and binding of Zn2+ by EDTA indicated that Zn2+ was associated with the cell fraction, and inhibition of hemolysin activity was specifically mediated by Zn2+. When the spirochetes were washed after incubation in the presence of ZnSO4 for 2 cycles and incubated in fresh PBS-GR without Zn2+, inhibition of hemolysin activity remained unchanged, indicating that the inhibitory effect of ZnSO4 was due to a direct action of ZnSO4 on the spirochetes. Since neither the viability of the spirochetes nor the activity of pre-formed hemolysin were affected by the presence of ZnSO4, the inhibitory effect of Zn2+ cations was attributed to reduced biosynthesis by viable S. hyodysenteriae cells rather than interference of Zn2+ cations with lysis of erythrocytes by the hemolysin. Transmission electron microscopic examination of spirochetes after incubation in PBS-GR containing ZnSO4 revealed clumping of ribosomes and clearing of cell cytoplasm.

Animals↗
PubMed1995

Swine dysentery: more unknown than known.

Swine dysentery (SD) is an economically important disease. It is caused by the spirochete Serpulina hyodysenteriae. In order to minimize the economic damage of SD, several methods to control this disease are recommended. Whereas hygienic measures and use of antimicrobials are actually practised for prevention, detection and exclusion of carriers of S. hyodysenteriae and vaccination against the disease still needs further attention. The last two methods require reliable and sensitive diagnostic tests and understanding of the pathogenesis of and immune development against SD. At present the detection of all individual carriers of S. hyodysenteriae is not yet assured, since the tests for screening individual animals are not satisfactorily evaluated as far as sensitivity and/or specificity are concerned. Studies on the pathogenesis of SD have been performed to develop a vaccine. Besides hemolysin/cytotoxin production, no other virulence factors have been identified with certainty for S. hyodysenteriae. Recently however, further indications for a role of motility in the pathogenesis of SD have been obtained. In this manuscript we summarize the most relevant recent findings.

Animals↗
PubMed1996

Identification and characterization of genus-specific epitopes of Serpulina species using monoclonal antibodies.

Four murine monoclonal antibodies (mAbs) designated as C9E8, A10, G12, and G8 which recognized both Serpulina hyodysenteriae and S. innocens were produced and characterized. The mAbs reacted with whole cell antigens in ELISA, indirect immunofluorescence and immunoblot assays. The mAbs did not show any cross reactivity in rapid dot ELISA or immunoblot assay with Leptospira icterohemorrhagiae, Campylobacter jejuni and Escherichia coli. Treatment of whole cell suspension with proteinase K and sodium periodate indicated that the reacting epitopes of the mAbs were protein in nature. The genus-specific antigens were identified as heat-stable proteins with molecular weight in the range of 26 to 45 kDa. Immunofluorescence and immunogold labelling studies showed that the antibody-binding epitopes were exposed on the outer-surface of the spirochaetal cell wall. The mAbs inhibited growth of reference strains of both S. hyodysenteriae and S. innocens in vitro but failed to cause agglutination. The detection of spirochaetal forms directly in fecal smears or paraffin-embeded tissue sections from experimentally infected pigs indicated that such mAbs were potentially useful for the diagnosis of swine spirochaetosis. This is the first report of mAbs identifying and characterizing common antigens of porcine Serpulina.

Animals↗
PubMed1996

Motility and chemotaxis in Serpulina hyodysenteriae.

Chemotactic- or motility-regulated mucus association appears to be the predominant mechanism of mucosal association by the causative agent of swine dysentery, Serpulina hyodysenteriae. In the present study, a modification of the Adler capillary assay was used to evaluate the chemotactic responses of S. hyodysenteriae to a variety of potential stimuli. First, however, it became necessary to study factors that influenced motility of the spirochete in vitro, since standard cultivation methods produced motility inferior to that observed for in vivo grown cells. A number of factors were found to influence S. hyodysenteriae motility, but of these growth medium and growth phase appeared to be the most important. The type and even batch of culture medium also were found to have a significant influence on S. hyodysenteriae motility. Optimal motility and chemotaxis for S. hyodysenteriae was observed when the cells were harvested in mid- to late-log phase, and in vivo-like motility could be induced by suspending the cells in physiologic saline. S. hyodysenteriae was strongly attracted to hog gastric mucin, certain concentrations of blood, L-fucose, L-serine and other compounds. Selected sugars and other amino acids did not serve as chemoattractants for S. hyodysenteriae. The chemotactic response of S. hyodysenteriae toward L-fucose and L-serine, constituents of mucin, may be important factors in the affinity of the spirochete for the mucus in the intestinal tract of swine.

Amino Acids↗
PubMed2005

D-ribose utilisation differentiates porcine Brachyspira pilosicoli from other porcine Brachyspira species.

D-ribose utilisation was studied in 60 Brachyspira pilosicoli strains and 35 strains of other Brachyspira species, the majority of which were of porcine origin. Utilisation of D-ribose was demonstrated indirectly by measuring the reduction in pH of densely inoculated tryptone-peptone broth supplemented with 7% foetal calf serum and 1% D-ribose. Among B. pilosicoli strains, the mean reduction in pH units was 1.72 (range 0.95-2.28) in broth with D-ribose and 0.27 (range 0.10-0.40) in sugar-free control broth. For Brachyspira strains other than B. pilosicoli, the corresponding reductions in pH units were 0.37 (range 0.12-0.49) and 0.37 (range 0.15-0.58). In conclusion, porcine B. pilosicoli can be differentiated from other porcine Brachyspira species by a test for D-ribose utilisation.

Animals↗
PubMed2004

Outer membrane proteins of pathogenic spirochetes.

Pathogenic spirochetes are the causative agents of several important diseases including syphilis, Lyme disease, leptospirosis, swine dysentery, periodontal disease and some forms of relapsing fever. Spirochetal bacteria possess two membranes and the proteins present in the outer membrane are at the site of interaction with host tissue and the immune system. This review describes the current knowledge in the field of spirochetal outer membrane protein (OMP) biology. What is known concerning biogenesis and structure of OMPs, with particular regard to the atypical signal peptide cleavage sites observed amongst the spirochetes, is discussed. We examine the functions that have been determined for several spirochetal OMPs including those that have been demonstrated to function as adhesins, porins or to have roles in complement resistance. A detailed description of the role of spirochetal OMPs in immunity, including those that stimulate protective immunity or that are involved in antigenic variation, is given. A final section is included which covers experimental considerations in spirochetal outer membrane biology. This section covers contentious issues concerning cellular localization of putative OMPs, including determination of surface exposure. A more detailed knowledge of spirochetal OMP biology will hopefully lead to the design of new vaccines and a better understanding of spirochetal pathogenesis.

Amino Acid Sequence↗