antigenic properties of borrelia burgdorferi isolated from ixodes ovatus and ixodes persulcatus in hokkaido, japan.spirochete strains hp3 and ho14, isolated from ixodes persulcatus and i. ovatus in hokkaido in 1989, were the first isolates of borrelia burgdorferi, the etiological agent of lyme disease, to be recognized in japan. antigenic properties of the japanese strains were compared with those of the strains isolated in the united states (b31 and 297) and europe (irs, p/gau, p/bi, 2/b45, and 3/b56) by western blotting (immunoblotting), by using monoclonal antibodies (mabs) against strains b31 and p/bi. t ...19911761676
immunological properties of borrelia burgdorferi isolated from the ixodes ovatus in shizuoka, japan.three strains of spirochetes (ika1 to 3) were isolated from the midgut of ixodes ovatus collected in the ikawa region of the northern part of shizuoka, japan. these isolates had eight flagella, and their size and other morphological features were similar to borrelia burgdorferi. they showed similar motility and reacted with monoclonal antibody (mab) h9724 against borrelial flagella and with mab h5332 against the outer surface protein a. these strains showed similar sds-page profiles to that of b ...19911779892
antibodies to borrelia burgdorferi in dogs in hokkaido.during 1985 to 1990, serum samples were obtained from 229 healthy dogs. the dogs lived in hokkaido, known to be infested with ticks. an enzyme-linked immunosorbent assay (elisa) was used to detect igg and igm antibodies against borrelia burgdorferi ho14 and hp3, which were isolated from ixodes ovatus and i. persulcatus in the area. igg antibody to b. burgdorferi ho14 was detected in 8.8% (1985), 16.4% (1987) and 18.5% (1990). igm antibody to the bacteria was detected in 1.8% (1987) and 2.5% (199 ...19902098630
characterization of borrelia species isolated from ixodid ticks, ixodes ovatus.thirty-two borrelia isolates were obtained from the adult stage of ixodid ticks, ixodes ovatus, collected in various localities in japan. borrelial isolates were cultivated and analyzed by polyacrylamide gel electrophoresis, with monoclonal antibodies, by pulsed field gel electrophoresis, and by genomic southern hybridization. all borrelial isolates showed similar protein profiles and monoclonal antibody reactivities, while plasmid profiles were rather diverse. genomic hybridization using rrna g ...19937903788
species-specific plasmid sequences for pcr identification of the three species of borrelia burgdorferi sensu lato involved in lyme disease.species-specific sequences were shown to be carried by plasmids of the three main species of borrelia burgdorferi sensu lato involved in lyme disease. libraries of the 16-, 33-, and 25-kb plasmids of b. burgdorferi sensu stricto, borrelia garinii, and borrelia afzelii, respectively, were then built and used to isolate species-specific sequences. after sequencing of the cloned inserts, three sets of primers were designed. they were shown to determine species-specific pcr amplification products. t ...19989431963
analysis of the organization of multicopy linear- and circular-plasmid-carried open reading frames in borrelia burgdorferi sensu lato isolates.plasmid cp8.3 of borrelia afzelii ip21 carries several open reading frames (orfs) and a 184-bp inverted repeat (ir) element. it has been speculated that this plasmid may encode factors involved in virulence or infectivity. in this report, we have characterized the distribution, molecular variability, and organization of orfs 1, 2, and 4 and the ir elements among isolates of the borrelia burgdorferi sensu lato complex. orfs 1 and 2 are contained within a segment of cp8.3 that is bordered by the i ...19989488408
lyme disease in taiwan: first human patient with characteristic erythema chronicum migrans skin lesion.we report herein the first laboratory-diagnosed case of lyme disease in a human in taiwan. a 45-year-old taiwanese man living in taipei, in northern taiwan, had an expanding skin lesion (measuring 23 by 15 cm) on his abdomen for 2 to 3 weeks and recurrent attacks of pain and swelling of the knee joint. serologic tests indicated a significantly elevated titer of antibody to borrelia burgdorferi. after appropriate antibiotic treatment for 3 weeks, the skin lesion was cured and the joint swelling w ...19989508317
genetic divergence and evolutionary instability in ospe-related members of the upstream homology box gene family in borrelia burgdorferi sensu lato complex isolates.a series of related genes that are flanked at their 5' ends by a conserved upstream sequence element called the upstream homology box (uhb) have been identified in borrelia burgdorferi. these genes have been referred to as the uhb or erp gene family. we previously demonstrated that among a limited number of b. burgdorferi isolates, the uhb gene family is variable in composition and organization. prior to this report the uhb gene family in other species of the b. burgdorferi sensu lato complex ha ...19989746562
phenotypic and genetic characterization of a novel borrelia burgdorferi sensu lato isolate from a patient with lyme borreliosis.borrelia burgdorferi sensu lato a14s was cultured from a skin biopsy specimen of a patient with erythema migrans in the netherlands. this isolate had a unique dna fingerprint pattern compared to 135 other b. burgdorferi sensu lato isolates. in this study, the isolate a14s was further characterized by protein analysis with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) and reactivity with various monoclonal antibodies. in addition, the 16s rrna, ospa, and ospc genes, as well ...199910449497
molecular typing of borrelia burgdorferi sensu lato: taxonomic, epidemiological, and clinical implications.borrelia burgdorferi sensu lato, the spirochete that causes human lyme borreliosis (lb), is a genetically and phenotypically divergent species. in the past several years, various molecular approaches have been developed and used to determine the phenotypic and genetic heterogeneity within the lb-related spirochetes and their potential association with distinct clinical syndromes. these methods include serotyping, multilocus enzyme electrophoresis, dna-dna reassociation analysis, rrna gene restri ...199910515907
lyme disease borrelia species in northeastern china resemble those isolated from far eastern russia and japan.fifty-nine borrelia burgdorferi sensu lato culture isolates collected from northeastern china were characterized by 5s-23s rrna intergenic spacer restriction fragment length polymorphism (rflp) analysis and reactivity with monoclonal antibodies (mabs). among 59 culture isolates, 30 (50.8%) were borrelia garinii and 17 (28.8%) were borrelia afzelii, 2 were mixtures composed of b. garinii with rflp pattern b and b. garinii with pattern c, and 9 were mixtures composed of b. garinii and b. afzelii. ...19989647853
prevalence of lyme disease borrelia spp. in ticks from migratory birds on the japanese mainland.borrelia sp. prevalence in ticks on migratory birds was surveyed in central japan. in autumn, a total of 1,733 birds representing 40 species were examined for ticks. a total of 361 ticks were obtained from 173 birds of 15 species, and these ticks were immature haemaphysalis flava (94.4%), haemaphysalis longicornis, ixodes columnae, ixodes persulcatus, ixodes turdus, and an unidentified ixodes species. of these, 27 juveniles of h. flava on turdus pallidus, turdus cardis, or emberiza spodocephala, ...200010698761
identification of novel insertion elements, restriction fragment length polymorphism patterns, and discontinuous 23s rrna in lyme disease spirochetes: phylogenetic analyses of rrna genes and their intergenic spacers in borrelia japonica sp. nov. and genomic group 21038 (borrelia andersonii sp. nov.) isolates.borrelia spp. associated with lyme disease possess an rrna gene organization consisting of a single 16s rrna gene followed by a spacer of several kilobases and a tandem repeat of a 23s (rrl)-5s (rrf) rrna gene cluster. the restriction fragment length polymorphism (rflp) patterns for these genes have been widely used to classify lyme disease spirochete isolates. we analyzed the rrna gene organization and sequences for two ixodes ovatus isolates from japan (ika2 and ho14) and two group 21038 isola ...19957494041
tick bite: two cases studied by scanning electron microscopy.the attachment of ticks to human skin has been studied by scanning electron microscopy. intact specimens of ixodes ovatus and ixodes persulcatus were examined, and we also studied the skin of two patients who had been bitten by these two species. in the first case, the remains of the tick were visible and a homogeneous cement-like substance was observed on the dorsal hypostome and in the dermis, suggesting that the tick attaches itself to the host skin by a secretion. in the second case, the api ...19846696839
characterization of borrelia burgdorferi isolated from ixodes persulcatus and ixodes ovatus ticks in japan.the lyme disease spirochete borrelia burgdorferi was detected in the adult stage of the ixodid ticks ixodes persulcatus and i. ovatus collected in various localities in japan. the total prevalence values were 16.6% of 777 i. persulcatus and 23.6% of 687 i. ovatus. sixty-two (63.9%) of 97 isolates from i. persulcatus contained the 30-34-kd heterogeneous outer surface protein a (ospa) that reacted with monoclonal antibody h5332. in contrast, all 128 isolates from i. ovatus were homogeneous with re ...19921279996
detection of ehrlichia platys dna in brown dog ticks (rhipicephalus sanguineus) in okinawa island, japan.thirty-two rhipicephalus sanguineus females collected from eight free-roaming dogs in okinawa island, japan, were examined for ehrlichial dna by 16s rrna-based pcr and subsequent sequencing. partial sequences of ehrlichia platys 16s rrna (678 to 679 bp) were detected in three ticks (9.4%) from two dogs. this is the first report of detection of e. platys in japan, and also the first report of detection in ticks.200011060094
genetic diversity of borrelia burgdorferi in lyme disease patients as determined by culture versus direct pcr with clinical specimens.two hundred seventeen isolates of borrelia burgdorferi originally cultured from skin biopsy samples or blood of early lyme disease patients were genetically characterized by pcr-restriction fragment length polymorphism (rflp) typing of the 16s-23s ribosomal dna intergenic spacer. three major rflp types were observed. of the cultured isolates, 63 of 217 (29.0%) were type 1, 85 of 217 (39.2%) were type 2, and 58 of 217 (26.7%) were type 3; mixtures of two rflp types were obtained in 6.0% (13 of 21 ...19999986813
genetic heterogeneity of borrelia burgdorferi sensu lato in ixodes ricinus ticks collected in belgium.borrelia burgdorferi sensu lato (s.l.), the etiological agent of lyme disease, is transmitted by the bite of ixodes ricinus. four hundred eighty-nine ticks, collected in four locations of a region of southern belgium where lyme disease is endemic, were examined for the presence of the spirochete. in a pcr test with primers that recognize a chromosomal gene of all strains, 23% of the ticks were found to be infected. the species b. burgdorferi s.l. comprises at least three pathogenic genomospecies ...19989774592
genospecies identification and characterization of lyme disease spirochetes of genospecies borrelia burgdorferi sensu lato isolated from rodents in taiwan.lyme disease spirochetes of the genospecies borrelia burgdorferi sensu lato were identified and characterized for the first time in taiwan. seven isolates, designated twkm1 to twkm7, were purified from the ear tissues of three species of rodents captured from seven localities of taiwan. the immunological characteristics of these taiwan isolates were compared with those of other genospecies of lyme disease spirochetes by analyzing the protein profiles and reactivities with b. burgdorferi-specific ...19989774551
cloning and molecular characterization of a multicopy, linear plasmid-carried, repeat motif-containing gene from borrelia turicatae, a causative agent of relapsing fever.borrelia turicatae is one of several spirochete species that can cause relapsing fever. here, we describe the identification and characterization of a gene from b. turicatae and other relapsing-fever spirochetes that exhibits homology with the rep+ and orf-e gene families of the lyme disease spirochetes. this gene, which we have designated repa, encodes a putative protein of 30.2 kda with an isoelectric point of 4.69. the central region of repa harbors a series of amino acid repeat motifs which ...19989733706
molecular and evolutionary characterization of the cp32/18 family of supercoiled plasmids in borrelia burgdorferi this study, we characterized seven members of the cp32/18 family of supercoiled plasmids in borrelia burgdorferi 297. complete sequence analysis of a 21-kb plasmid (cp18-2) confirmed that the strain 297 plasmids are similar in overall content and organization to their b31 counterparts. of the 31 open reading frames (orfs) in cp18-2, only three showed sequence relatedness to proteins with known functions, and only one, a para/sopa ortholog, was related to nonborrelial polypeptides. besides the ...200010678977
isolation of tick-borne encephalitis virus from ixodes ovatus (acari: ixodidae) in japan.a case of tick-borne encephalitis (tbe) was found in a farming area located in the southern part of hokkaido, japan, in 1993. tbe viruses were isolated from sentinel dogs in the area where the human case occurred in 1995. ticks were collected in the area by 2 collection methods in 1995 and virus isolation was conducted on ticks in 1995 and 1996. ixodes ovatus neumann was found to be the predominant tick species in the area. in 1996, 2 virus strains were isolated from 600 i. ovatus ticks (300 fem ...19989615539
detection of ehrlichial infection by pcr in dogs from yamaguchi and okinawa prefectures, japan.species-specific nested polymerase chain reaction (pcr) was used to detect the presence of possible canine ehrlichial agents (ehrlichia canis, e. chaffeensis, e. ewingii, e. equi and e. platys) and monocytic ehrlichial agents found in japan (e. muris and a recently discovered ehrlichia species detected from ixodes ovatus) in blood samples from dogs in yamaguchi and okinawa prefecture, japan. partial sequence of e. platys was detected from 1 of 67 dogs (1.5%) tested from yamaguchi prefecture and ...200111503912
infectivity and early antibody response to borrelia burgdorferi sensu lato isolated in japan in outbred mice.borrelia burgdorferi sensu lato isolated from ixodes ovatus (b. japonica), i. persulcatus and patients with erythema migrans (em) in japan were determined on infectivity and arthritis induction-activity in outbred mice. infectivity of b. japonica was weak and did not induce the development of footpad swelling by subcutaneous (s.c.) inoculation into the footpad. challenged strain, no129-m of b. japonica, to ddy mice were reinoculated to the mice at various cell numbers (1 x 10-1 x 10(6) cells/mou ...19947799835
citrate synthase gene sequence: a new tool for phylogenetic analysis and identification of ehrlichia.the sequence of the citrate synthase gene (glta) of 13 ehrlichial species (ehrlichia chaffeensis, ehrlichia canis, ehrlichia muris, an ehrlichia species recently detected from ixodes ovatus, cowdria ruminantium, ehrlichia phagocytophila, ehrlichia equi, the human granulocytic ehrlichiosis [hge] agent, anaplasma marginale, anaplasma centrale, ehrlichia sennetsu, ehrlichia risticii, and neorickettsia helminthoeca) have been determined by degenerate pcr and the genome walker method. the ehrlichial ...200111526124
molecular typing of borrelia burgdorferi sensu lato by randomly amplified polymorphic dna fingerprinting study whether pathogenic clusters of borrelia burgdorferi sensu lato strains occur, we typed 136 isolates, cultured from specimens from patients (n = 49) with various clinical entities and from ticks (n = 83) or dogs (n = 4) from different geographic regions, by randomly amplified polymorphic dna (rapd) fingerprinting with four arbitrary primers. the rapd patterns were reproducible up to the 95% similarity level as shown in duplicate experiments. in these experiments the purified dnas prepare ...19989508310
organization of ribosomal rna genes in borrelia burgdorferi sensu lato isolated from ixodes ovatus in japan.borrelia burgdorferi sensu lato was obtained from adult ixodid ticks, ixodes ovatus, collected in nagano, japan, and was named nt112. the genomic dna was digested with enzymes, electrophoresed, blotted and hybridized with rrna gene probes obtained from b. burgdorferi sensu stricto b31. the results showed that the borrelial chromosome contains a single rrs (16s rrna gene) sequence and two copies of rrl/rrf (23s/5s rrna genes) sequences. the rrl/rrf genes were tandemly repeated at intervals of 3.2 ...19937507551
location and ultrastructure of borrelia japonica in naturally infected ixodes ovatus and small mammals.the internal organs of ixodes ovatus and the ears of wild rodents (apodemus speciosus, eothenomys smithii) and an insectivore (crocidura dsinezumi) were cultured to isolate borreliae; positive samples were examined for the distribution and dissemination of spirochetes in the host tissues using electron microscopy. seven isolates were derived from the unfed ticks and the three species of mammals. these isolates were identified as borrelia japonica judging from the outer surface protein profile us ...19979087963
molecular survey of ehrlichia infection in ticks from animals in yamaguchi prefecture, japan.a total of 82 ticks collected from wild animals and dogs in yamaguchi prefecture, japan were examined for ehrlichia infection by using polymerase chain reaction (pcr) primers that amplify dna of most members of the genus ehrlichia. a dna sample from an ixodes ovatus nymph from a bear in yamaguchi prefecture, japan, was positive in the screening pcr. subsequent pcr using two sets of primers yielded a 1431 bp segment of the 16s rrna gene and the sequence was very similar to those of e. chaffeensis ...200111511421
seasonal correlation of sporadic schizophrenia to ixodes ticks and lyme borreliosis.background: being born in winter and spring is considered one of the most robust epidemiological risk factors for schizophrenia. the aetiology and exact timing of this birth excess, however, has remained elusive so far. since during phylogeny, borrelia dna has led to multiple germ-line mutations within the cb1 candidate gene for schizophrenia, a meta analysis has been performed of all papers on schizophrenic birth excesses with no less than 3000 cases each. all published numerical data were then ...200212453316
ehrlichia chaffeensis: a prototypical emerging pathogen.ehrlichia chaffeensis is an obligately intracellular, tick-transmitted bacterium that is maintained in nature in a cycle involving at least one and perhaps several vertebrate reservoir hosts. the moderate to severe disease caused by e. chaffeensis in humans, first identified in 1986 and reported for more than 1,000 patients through 2000, represents a prototypical "emerging infection." knowledge of the biology and natural history of e. chaffeensis, and of the epidemiology, clinical features, and ...200312525424
a new genomic species in borrelia burgdorferi sensu lato isolated from japanese ticks.five borrelia strains (ika2, ho14, cow611c, 0612 and f63b) isolated from ixodes ovatus ticks in japan were analysed by dna-dna hybridization experiments, ribotyping, pulsed-field gel electrophoresis and protein electrophoresis. dna relatedness set these strains in a new genomic species within the borrelia burgdorferi complex; this species appears to be restricted to japan and could be non-pathogenic for humans. the ribotype and pulsotype of strain ika2 were atypical of the new genomic species.19938190992
glycerol-3-phosphate acquisition in spirochetes: distribution and biological activity of glycerophosphodiester phosphodiesterase (glpq) among borrelia species.relapsing-fever spirochetes achieve high cell densities (>10(8)/ml) in their host's blood, while lyme disease spirochetes do not (<10(5)/ml). this striking contrast in pathogenicity of these two groups of bacteria suggests a fundamental difference in their ability to either exploit or survive in blood. borrelia hermsii, a tick-borne relapsing-fever spirochete, contains orthologs to glpq and glpt, genes that encode glycerophosphodiester phosphodiesterase (glpq) and glycerol-3-phosphate transporte ...200312562805
prevalence of lyme borrelia in ticks, especially ixodes persulcatus (acari: ixodidae), in central and western japan.prevalence of lyme borrelia in unfed ticks was surveyed in central and western japan during spring from 1991 to 1993. the tick fauna was diverse; ticks obtained consisted of four genera and more than 12 identified species, and both southern and northern species coexist with altitudinal separation. midguts of ticks were cultured in bsk medium for spirochetal isolation. borrelia-positive rates for adults of both a common species, ixodes ovatus neumann, and a northern species, ixodes persulcatus sc ...19948057323
ospa heterogeneity of borrelia valaisiana confirmed by phenotypic and genotypic analyses.although european borrelia burgdorferi sensu lato isolates have been divided into five genospecies, specific tools for the serotype characterization of only three genospecies are available. monoclonals antibodies (mabs) h3ts, d6 and i17.3 identify b. burgdorferi sensu stricto (ss.), b. garinii and b. afzelii respectively, but no mabs are available to identify b. valaisiana. in the same way, specific primers exist to amplify the ospa gene of b. burgdorferi ss., b. garinii and b. afzelii. the aim ...200312823864
susceptibility of ixodes persulcatus and i. ovatus (acari: ixodidae) to lyme disease spirochetes isolated from humans in japan.susceptibility of ixodes persulcatus schulze and ixodes ovatus neumann to lyme disease spirochetes isolated from humans was studied under laboratory conditions. six isolates (jem3, jem4, jem5, jem6, jem7, and jem8) from patients in japan were used for the study. mongolian jirds were inoculated intraperitoneally with each of the isolates. larval ticks of either i. persulcatus or i. ovatus were allowed to feed on the jirds and reared for development into nymphs. in all human isolates examined, the ...19948057322
new ehrlichia species closely related to ehrlichia chaffeensis isolated from ixodes ovatus ticks in ehrlichia strains (six hf strains and one anan strain) that were obtained from laboratory mice by intraperitoneally inoculating homogenates of adult ixodes ovatus collected in japan were characterized. 16s rrna sequences of all six hf strains were identical, and the sequences were 99.7, 98.2, and 97.7% identical to those of anan strain, ehrlichia chaffeensis (human monocytic ehrlichiosis agent), and e. muris, respectively. partial groel amino acid sequencing also revealed that the six hf s ...200010747103
differentiation of borrelia burgdorferi sensu lato on the basis of rna polymerase gene (rpob) sequences.we determined the nucleotide sequences (329 bp) of the rpob dnas from 22 reference strains of borrelia. no insertions or deletions were observed. deduced amino acid sequences of amplified rpob dna comprised 109 amino acid residues (n(450) to m(558) [escherichia coli numbering]). all amino acid sequences were identical with the exception of those of borrelia lusitaniae potib2 (t(461)-->a) and b. bissettii dn127 (i(498)-->v). each species of b. burgdorferi sensu lato was differentiated as a distin ...200010878043
characterization of monoclonal antibodies for identification of borrelia japonica, isolates from ixodes ovatus.monoclonal antibodies for identification of borrelia japonica isolated from tick, ixodes ovatus and long-tailed shrew, sorex unguiculatus in japan and borrelia related to lyme disease (borrelia burgdorferi sensu lato) were prepared and characterized. all isolates belonging to b. japonica and isolates from i. dentatus and cottontail rabbit in north america reacted with mab o1441b against flagellin which was prepared from immunized mice with strain ho14, type strain of b. japonica, but isolates fr ...19947935066
detection of antibodies against borrelia burgdorferi in patients with uveitis.we determined the antibody response against borrelia burgdorferi strains isolated from japanese ixodes ovatus and ixodes persulcatus ticks by enzyme-linked immunosorbent assay and indirect immunofluorescence assay of serum specimens from 127 patients with uveitis. we examined samples of serum from japanese patients with unclassified uveitis, iridocyclitis caused by herpes zoster virus, behçet's disease, vogt-koyanagi-harada syndrome, sarcoidosis, or other conditions (sympathetic ophthalmia, posn ...19911882917
evaluation of groel gene analysis for identification of borrelia burgdorferi sensu lato.the nucleotide sequences of the groel genes, the flagellin genes, and the 16s rrna genes from 22 reference strains of borrelia were compared. groel sequence analysis is useful not only in interspecies differentiation but also in intraspecies differentiation of borrelia afzelii and borrelia garinii isolates.200415004091
detection of ehrlichial dna in haemaphysalis ticks recovered from dogs in japan that is closely related to a novel ehrlichia sp. found in cattle ticks from tibet, thailand, and africa.tick dna samples from dogs in japan were examined for ehrlichia infection by 16s rrna gene-based pcr and sequencing. three positive samples were detected from haemaphysalis ticks, and higher levels of similarity (98.46 to 99.06%) were found to recently detected ehrlichia spp. from cattle ticks in tibet, thailand, and africa.200415004117
prevalence of lyme borreliosis spirochetes in ixodid ticks of japan, with special reference to a new potential vector, ixodes ovatus (acari: ixodidae).to determine the vectors of lyme borreliosis in japan, the ixodid ticks taken in hokkaido, fukushima, nagano, ehime, and kochi prefectures were examined individually for spirochetal infections by culturing their midgut tissues in bsk medium. the cultivable spirochetes identified as borrelia burgdorferi were detected in ixodes persulcatus schulze adults (15.5% of 634), nymph (6.7% of 15) and ixodes ovatus neumann adult (9.6% of 188) from hokkaido, i. ovatus adults (25.5% of 47) from fukushima, an ...19921495032
genetic analysis of borrelia garinii ospa serotype 4 strains associated with neuroborreliosis: evidence for extensive genetic homogeneity.infection with borrelia garinii outer surface protein (osp) a serotype 4 strains has been correlated with the development of neuroborreliosis in lyme borreliosis patients in europe. ospa serotype 4 isolates have been recovered primarily from human cerebrospinal fluid, suggesting a tropism for this environment. previous studies with monoclonal antibodies directed against ospa and ospc demonstrated that ospa serotype 4 strains are antigenically closely related. in view of the pronounced antigenic ...199910565915
prevalence of antibodies to borrelia spirochetes among wild small rodents in central and western japan.field rodents serve as a reservoir for lyme disease spirochetes. to evaluate the antibody responses of rodents against different borrelia species in relation to fauna of vector ticks feeding on them, we examined 272 sera of wild rodents, apodemus speciosus, a. argenteus, and eothenomys smithii, obtained in 27 locations in central and western japan from 1981 to 1994. as to prevalences by rodent species using immunoperoxidase test, a. speciosus, a. argenteus and e. smithii showed 29.4%, 11.6% and ...19958551974
transfusion-acquired, autochthonous human babesiosis in japan: isolation of babesia microti-like parasites with hu-rbc-scid mice.we have isolated piroplasms from a patient who developed the first case of human babesiosis in japan by using nod/shi-scid mice whose circulating erythrocytes (rbcs) had been replaced with human rbcs (hu-rbc-scid mice). following inoculation of the patient's blood specimen into hu-rbc-scid mice, parasites proliferated within the human rbcs in the mice, resulting in a high level of parasitemia. parasite dna was prepared from blood samples of the patient and the mice, and the nuclear small-subunit ...200011101588
molecular and pathogenic characterization of borrelia burgdorferi sensu lato isolates from spain.fifteen borrelia burgdorferi sensu lato isolates from questing ticks and skin biopsy specimens from erythema migrans patients in three different areas of spain were characterized. four different genospecies were found (nine borrelia garinii, including the two human isolates, three b. burgdorferi sensu stricto, two b. valaisiana, and one b. lusitaniae), showing a diverse spectrum of b. burgdorferi sensu lato species. b. garinii isolates were highly variable in terms of pulsed-field gel electropho ...200011060064
genomic analysis of borrelia japonica sp. nov. isolated from ixodes ovatus in japan.genetic characteristics of 12 borrelia isolates from the tick, ixodes ovatus, i. persulcatus, and the rodent, apodemus speciosus ainu, in japan were compared to members of the three genospecies of borrelia burgdorferi sensu lato; b. burgdorferi sensu stricto, b. garinii and group vs461. the methods used in this study were the quantitative microplate dna hybridization assay and restriction fragment length polymorphism (rflp) analyses of the flagellin structural genes and the 16s rrna genes. the s ...19937905183
lone star tick-infecting borreliae are most closely related to the agent of bovine borreliosis.although borrelia theileri, the agent of bovine borreliosis, was described at the turn of the century (in 1903), its relationship with borreliae causing lyme disease or relapsing fever remains undescribed. we tested the previously published hypothesis that spirochetes infecting lone star ticks (amblyomma americanum) may comprise b. theileri by analyzing the 16s ribosomal dnas (rdnas) and flagellin genes of these spirochetes. b. theileri, the amblyomma agent, and b. miyamotoi formed a natural gro ...200111158095
transmission of borrelia garinii ospa serotype 4 to balb/c mice by ixodes ricinus ticks collected in the europe, borrelia garinii ospa serotype 4 has been isolated from the cerebrospinal fluid of patients but, up to now, has never been identified among culture isolates from ixodes ricinus ticks. this information raises the question of whether ospa serotype 4 is transmitted by i. ricinus in nature. in the present study, i. ricinus nymphs collected in an area of endemicity in southern germany were allowed to feed on mice. cultivation of ear biopsy specimens showed that six of seven b. garinii-infe ...200111230451
analysis of the 16s rrna gene sequence of anaplasma centrale and its phylogenetic relatedness to other ehrlichiae.the nucleotide sequence of the anaplasma centrale 16s rrna gene was determined and compared with the sequences of ehrlichial bacteria. the sequence of a. centrale was closely related to anaplasma marginale by both level-of-similarity (98.08% identical) and distance analysis. a species-specific pcr was developed based upon the alignment data. the pcr can detect a. centrale dna extracted from 10 infected bovine red blood cells in a reaction mixture. a. centrale dna was amplified in the reaction, b ...200111238202
isolation and characterization of borrelia burgdorferi sensu lato strains in an area of italy where lyme borreliosis is endemic.between 1993 and 1998, we isolated borrelia burgdorferi sensu lato from 55 of the 119 patients with clinically diagnosed lyme borreliosis who were admitted to "san martino" hospital in belluno, veneto, an adriatic region in northeastern italy where lyme borreliosis is endemic. upon hospitalization, all patients presented erythema migrans. isolates were typed using ribosomal dna pcr-restriction fragment length polymorphism (rflp) analysis of the rrfa-rrlb intergenic spacer. of the 41 isolates typ ...200111376066
[present status of lyme borreliosis and characterization of lyme disease borrelia isolated in japan].lyme disease is a multisystemic disorder caused by infection with borrelia burgdorferi sensu lato which is carried by ticks of the ixodes ricinus complex. the agent was discovered in 1982 in north america and the disease is recognized as an emerging infectious diseases in north america and europe. japanese borrelia isolates were characterized by genetic and immunologic analysis. isolates from ixodes ovatus were found to be unique by dna/dna hybridization analysis, restriction fragment length pol ...19979248350
molecular identification and analysis of borrelia burgdorferi sensu lato in lizards in the southeastern united states.lyme borreliosis (lb) group spirochetes, collectively known as borrelia burgdorferi sensu lato, are distributed worldwide. wild rodents are acknowledged as the most important reservoir hosts. ixodes scapularis is the primary vector of b. burgdorferi sensu lato in the eastern united states, and in the southeastern united states, the larvae and nymphs mostly parasitize certain species of lizards. the primary aim of the present study was to determine whether wild lizards in the southeastern united ...200515870353
tick-borne rickettsioses around the world: emerging diseases challenging old concepts.during most of the 20th century, the epidemiology of tick-borne rickettsioses could be summarized as the occurrence of a single pathogenic rickettsia on each continent. an element of this paradigm suggested that the many other characterized and noncharacterized rickettsiae isolated from ticks were not pathogenic to humans. in this context, it was considered that relatively few tick-borne rickettsiae caused human disease. this concept was modified extensively from 1984 through 2005 by the identif ...200516223955
genetic identification of rickettsiae isolated from ticks in japan.following the description in japan of japanese spotted fever, caused by rickettsia japonica, a search for the vector of this disease led to the isolation of several rickettsiae from various tick species. sixty-three rickettsial isolates were obtained from six different tick species, and six type strains were described by pcr and monoclonal antibody testing. we identified these six strains by amplification and sequencing of the genes encoding 16s rrna and citrate synthase. we confirmed that the i ...200212037083
analysis of the bmp gene family in borrelia burgdorferi sensu lato.bmpa, bmpb, bmpc, and bmpd are homologous borrelia burgdorferi lipoproteins of unknown functions, encoded by the bmp genes of paralogous chromosomal gene family 36. at least some of the bmp proteins are immunogens in infected vertebrate hosts. the genetic organization of the bmp region has been characterized for a variety of b. burgdorferi sensu lato strains by southern hybridization, pcr amplification, and dna sequencing. all four bmp genes were present in the same relative order in all b. burg ...200010715014
simultaneous detection of anaplasma marginale and a new ehrlichia species closely related to ehrlichia chaffeensis by sequence analyses of 16s ribosomal dna in boophilus microplus ticks from identify ehrlichial agents in boophilus microplus ticks, dna samples of b. microplus collected from the tibet autonomous region and sichuan province of china were screened by a nested pcr. sixteen of 43 (37%) dna samples of b. microplus from tibet were positive in nested pcr analysis. all 27 samples from sichuan were negative. the screen identified two ehrlichial agents based on different 16s rrna genes that were found after amplifying and sequencing the 5'-end fragments of the 16s rrna genes ...200212202567
ultrastructure of a japanese rickettsial strain genetically identified as rickettsia helvetica which was originally found in europe.a rickettsial strain io-1 has been isolated from a tick, ixodes ovatus, in japan and genetically identified as rickettsia helvetica, a member of the spotted fever group rickettsiae. ultrastructural observations were made on the microorganism. the ultrastructure of r. helvetica io-1 appeared to be generally the same as that previously shown for other rickettsiae of the spotted fever and typhus groups. the rickettsiae were primarily found free in the cytoplasm of l929 cultured cells. occasionally, ...200415272199
lyme disease borrelia spp. in ticks and rodents from northwestern may 1999, field surveys of lyme disease spirochetes were conducted around the tianshan mountains in xinjiang uygur autonomous region in northwestern people's republic of china. ixodes persulcatus ticks were obtained in a tianchi lake valley with primary forest, while the tick fauna was poor in the semidesert or at higher altitudes in this region. species identities were confirmed by molecular analysis in which an internal transcribed spacer sequence was used. of 55 adult ticks, 22 (40%) were ...200111679340
[spotted fever group rickettsiosis and vectors in kanagawa prefecture].primer pairs for pcr were designed from the gene encoding the 17,000-molecular-weight genus-common antigen of rickettsia japonica, rickettsia rickettsii, rickettsia conorii, rickettsia typhi and rickettsia prowazekii. primers r1, r2 were designed for amplifying the genomic dna from spotted fever group (sfg) rickettsiae and epidemic typhus rickettsiae. primers rj5, rj10 were designed for amplifying the genomic dna from only r. japonica. using the primers r1, r2, about a 540-bp fragment was observ ...19968741704
ehrlichiae and ehrlichial diseases in china.the various ticks collected from different areas of china were examined for the existence of ehrlichial agents by polymerase chain reaction (pcr) with genus- or species-specific primers designed on the basis of ehrlichial 16s rrna genes and sequence analyses. in southern china, e. chaffeensis was detected in amblyomma testudinarium ticks from infested cattle, haemaphysalis yeni ticks from hare, and ixodes ovatus ticks from muntiacus reevesi. e. canis was identified in rhipicephalus sanguineus ti ...200312860598
ixodid tick species recovered from domestic dogs in japan.the species of ixodid ticks (acari: ixodidae) recovered from domestic dogs in japan between september to november 2000 and april to june 2001 were identified. a total of 4122 ticks, including 1624 larvae, 1200 nymphs, 1016 females and 282 males were removed from 1221 dogs during these periods. haemaphysalis longicornis (neumann) was the most frequently found (40.3% of dogs), followed by h. flava (neumann) (16.1% of dogs), rhipicephalus sanguineus (latreille) (4.8% of dogs) and ixodes ovatus (neu ...200312680923
confirmation of tick bite by detection of antibody to ixodes calreticulin salivary protein.ticks introduce a variety of pharmacologically active molecules into their host during attachment and feeding in order to obtain a blood meal. people who are repeatedly exposed to ticks may develop an immune response to tick salivary proteins. despite this response, people usually are unaware of having been bitten, especially if they are not repeatedly exposed to ticks. in order to develop a laboratory marker of tick exposure that would be useful in understanding the epidemiology of tick-borne i ...200616928887
detection of antibodies to anaplasma phagocytophilum and ehrlichia chaffeensis antigens in sera of korean patients by western immunoblotting and indirect immunofluorescence assays.two hundred seventy one serum samples from south korean patients were tested to detect antibodies against anaplasma phagocytophilum (the human granulocytic ehrlichiosis agent) and ehrlichia chaffeensis (the human monocytic ehrlichiosis agent) by indirect fluorescent-antibody assay (ifa) and the western blot assay. these sera were collected from patients with symptoms of high fever. the rate of seropositivity for orientia tsutsugamushi was 50.9% by ifa at the public health & environmental researc ...200314607867
phylogenetic analysis of spotted fever group rickettsiae based on glta, 17-kda, and rompa genes amplified by nested pcr from ticks in order to understand the natural situation of rickettsiae in the ticks in japan, the rickettsial genes, glta gene, rompa gene, and 17-kda gene, were amplified from the ticks by nested pcr. the prevalences of rickettsial glta genes among haemaphysalis formosensis, h. longicornis, h. megaspinosa, ixodes ovatus, h. flava, h. kitaokai, and i. persulcatus were 62, 57, 24, 24, 19, 13, and 10%, respectively; 26% (186/722) being the average. the glta genes amplified from the ticks were classified into ...200314638993
culture and phenotypic characterization of a wolbachia pipientis isolate.the recent isolation of wolbachia pipientis in the continuous cell line aa23, established from eggs of a strain of the asian tiger mosquito aedes albopictus, allowed us to perform extensive characterization of the isolate. bacterial growth could be obtained in c6/36, another a. albopictus cell line, at 28 degrees c and in a human embryonic lung fibroblast monolayer at 28 and 37 degrees c, confirming that its host cell range is broader than was initially thought. the bacteria were best visualized ...200314662922
seroepidemiological study of canine ehrlichial infections in yamaguchi prefecture and surrounding areas of japan.randomly selected serum samples from 150 dogs from yamaguchi and neighbouring prefectures were subjected to the indirect immunofluorescent assay to detect antibodies against ehrlichia canis, ehrlichia chaffeensis, ehrlichia muris and ehrlichia from ixodes ovatus. a total of 30 out of the 150 serum samples reacted with at least one of the antigens at a titer of 1:20 or more. considerable cross-reactivity was seen and most samples reacted with at least two different antigens. fifteen (10.0%) dogs ...200415350665
mechanisms of immunity to ehrlichia muris: a model of monocytotropic ehrlichiosis.ehrlichia species can cause life-threatening infections or chronic persistent infections. mechanisms of protective immunity were examined in an ehrlichia muris mouse model of monocytotropic ehrlichiosis. c57bl/6 mice possessed strong genetic resistance to e. muris of an undetermined mechanism. cd8 t lymphocytes were particularly important, as revealed by 81% fatalities for e. muris-infected, major histocompatibility complex class i gene knockout mice compared with no deaths for wild-type c3h mic ...200414742542
survey of rodents and ticks in human babesiosis emergence area in japan: first detection of babesia microti-like parasites in ixodes ovatus.babesia microti-like parasites were detected for the first time in ixodes ovatus in hyogo prefecture, japan, where two reported types of b. microti-like parasites were recognized in many rodents. of 80 adult i. ovatus ticks collected, 5 possessed the reported type and 1 possessed a new type of b. microti-like parasite.200415131209
first serologic evidence of human spotted fever group rickettsiosis in investigate the prevalence of spotted fever group rickettsioses in korea, a serosurvey of japanese spotted fever rickettsiosis in patients with acute febrile illness was conducted with an indirect immunofluorescence assay. overall, 19.88% of the patients were found to have polyvalent antibody against rickettsia japonica. this study is the first documentation of spotted fever group rickettsiosis in korea.200415131221
high-resolution genetic fingerprinting of european strains of anaplasma phagocytophilum by use of multilocus variable-number tandem-repeat analysis.anaplasma phagocytophilum is a widely distributed tick-borne pathogen of humans, livestock, and companion animals. we used in silico methods to identify 10 variable-number tandem-repeat (vntr) loci within the genome sequence of the a. phagocytophilum hz strain and used these data to develop a multilocus vntr-based typing scheme for the species. having confirmed the stability of four of the loci in replicates of the a. phagocytophilum strain that had been subjected to different numbers of passage ...200717442796
analysis of the genetic polymorphism of borrelia burgdorferi sensu lato by multilocus enzyme recent years, borrelia burgdorferi sensu lato has been subdivided into three species, borrelia burgdorferi sensu stricto, borrelia garinii, and borrelia afzelii, and a new species restricted to japan, borrelia japonica, has been isolated from ixodes ovatus. in addition, members of several new genomic groups have been found in america and in europe, suggesting that there are additional genospecies. in order to study the diversity of b. burgdorferi sensu lato, we analyzed 54 isolates, cultured ...19968573491
production of ifn-gamma by cd4 t cells is essential for resolving ehrlichia address the role of cellular immunity during ehrlichia infection, we have used a newly described model of monocytic ehrlichiosis that results from infection of mice by an ehrlichia that was isolated from an ixodes ovatus tick (ixodes ovatus ehrlichia, ioe). immunocompetent c57bl/6 and balb/c mice exhibited a dose-dependent susceptibility to ioe infection. mice infected with a high dose inoculum ( approximately 1000 organisms) exhibited pronounced thrombocytopenia, lymphopenia, anemia, and mor ...200415153508
borrelia sinica sp. nov., a lyme disease-related borrelia species isolated in china.a survey was performed for lyme disease borrelia in the southern part of china, in zhejiang, sichuan and anhui provinces, along the yangtze river valley, in may of 1997 and 1998. twenty isolates from ixodes granulatus, ixodes ovatus, apodemus agrarius and niviventer confucianus were obtained. these isolates were characterized by rflp of the 5s-23s rdna intergenic spacer, sequence analysis of the intergenic spacer, 16s rdna and flagellin gene, dna-dna hybridization analysis, sds-page and western ...200111594614
ultrastructure and phylogenetic analysis of 'candidatus neoehrlichia mikurensis' in the family anaplasmataceae, isolated from wild rats and found in ixodes ovatus ticks.a novel bacterium that infects laboratory rats was isolated from wild rattus norvegicus rats in japan. transmission electron microscopy of the spleen tissue revealed small cocci surrounded by an inner membrane and a thin, rippled outer membrane in a membrane-bound inclusion within the cytoplasm of endothelial cells. phylogenetic analysis of the 16s rrna gene sequence of the bacterium found in r. norvegicus rats and ixodes ovatus ticks in japan revealed that the organism represents a novel clade ...200415388752
[random amplified polymorphic dna analysis of the genomes among 7 species of ticks].to study genomic polymorphic dna and genetic distance of 7 species of ticks.200415587156
a case of tick-bite from ixodes ovatus neumann--a report from west japan.a 70-year-old male forestation worker had a tick-bite on the lower abdominal skin. the bite was treated by surgical excision of the tick together with the surrounding skin. the tick was identified as ixodes ovatus neumann through investigation of its morphological characteristics. this patient is the fourth case of a tick-bite from ixodes ovatus neumann in western japan.19892656810
experimental inoculation of beagle dogs with ehrlichia species detected from ixodes ovatus.three beagle dogs were inoculated with mice spleen/liver homogenate infected with ehrlichia species detected from ixodes ovatus (eio) and one dog was used as a control. all three infected dogs did not show clinical signs of disease except for mild pyrexia throughout the 41-day study period. splenomegaly was observed from day 7 post-inoculation (p.i.) in two of the dogs. hematological and biochemical abnormalities included mild thrombocytopenia, hypoproteinaemia, hypoalbuminaemia and increased c- ...200616309840
epidemiological survey of babesia species in japan performed with specimens from ticks collected from dogs and detection of new babesia dna closely related to babesia odocoilei and babesia divergens dna.detection and analysis of babesia species from ticks recovered from dogs in japan were attempted by pcr and nucleotide sequence analysis based on the 18s rrna gene, respectively. a total of 1136 ticks were examined for babesia dna by 18s rrna-based pcr and nucleotide sequencing. partial sequences of babesia canis vogeli dna were detected from six ticks in aomori, nara, hiroshima, oita, and okinawa prefectures; and babesia gibsoni asia-1 dna was also detected in four ticks in osaka, hiroshima, mi ...200312904344
histologic, serologic, and molecular analysis of persistent ehrlichiosis in a murine model.human monocytotropic ehrlichiosis caused by ehrlichia chaffeensis was reported in 1987. an animal model to study acute fatal ehrlichiosis in mice that has been developed closely resembles the fatal form of human monocytotropic ehrlichiosis. however, animal models for persistent infection in the genus ehrlichia in immunocompetent mice have not been characterized. we report the histopathological progression of ehrlichia muris infection in immunocompetent mice (akr and c57bl/6 strains) correlated w ...200415331423
survey of ixodid tick species on domestic cats in japan.various species of ixodid ticks, attached to domestic cats in japan, were identified in spring (april to june) and autumn (september to november). in the spring, a total of 282 ticks, including 61 larvae, 70 nymphs, 127 females and 24 males were collected from 126 cats. of these, 264 were identified up to the species level. in the spring, haemaphysalis longicornis was the most frequently (39.7%, 50/126) found tick species on feline hosts, followed by ixodes ovatus (35.0%, 44/126), ixodes nippone ...200312531297
essential role for humoral immunity during ehrlichia infection in immunocompetent mice.although cellular immunity is essential for host defense during intracellular bacterial infections, humoral immunity can also play a significant role in host defense during infection by some intracellular bacteria, including the ehrlichiae. antibodies can protect susceptible scid mice from fatal ehrlichia chaffeensis infection, an observation that has been hypothesized to involve the opsonization of bacteria released from host cells. to determine whether humoral immunity plays an essential role ...200516299294
tick infestation of sika deer (cervus nippon) in the western part of yamaguchi prefecture, japan.ticks were collected from 94 sika deer (cervus nippon) hunted in the western part of yamaguchi prefecture, japan from august to november 1999, and march to july 2000. haemaphysalis longicornis and h. yeni were the dominant species from april to august, while h. flava and h. megaspinosa were dominant in october, november and march. this is the first report of h. yeni in the mainland of japan. small numbers of h. kitaokai, amblyomma testudinarium and ixodes ovatus were also recorded.200212185317
overproduction of tnf-alpha by cd8+ type 1 cells and down-regulation of ifn-gamma production by cd4+ th1 cells contribute to toxic shock-like syndrome in an animal model of fatal monocytotropic ehrlichiosis.human monocytotropic ehrlichiosis (hme) is an emerging, life-threatening, infectious disease caused by ehrlichia chaffeensis, an obligate intracellular bacterium that lacks cell wall lps. we have previously developed an animal model of severe hme using a strain of ehrlichia isolated from ixodes ovatus ticks (ioe). to understand the basis of susceptibility to severe monocytotropic ehrlichiosis, we compared low and high doses of the highly virulent ioe strain and the less virulent ehrlichia muris ...200414734762
characterization of ehrlichia species from ixodes ovatus ticks at the foot of mt. fuji, japan.a total of 390 adult ticks (288 ixodes ovatus and 102 i. persulcatus ) collected at the foot of mt. fuji and two near cities in shizuoka prefecture, japan, were examined for ehrlichia infection by isolation with laboratory mice from whole tick tissues. ehrlichial dnas were detected from the spleens of mice inoculated with tissues from i. ovatus, but not i. persulcatus. the prevalence of ehrlichiae in the ticks was estimated to be ca. 3%. the 16s rdna analysis revealed that the sequences of 8 ehr ...200415502406
five cases of tick bite.reported here are five cases of tick bite: in a 2-year-old boy, a 3-year-old girl, a 72-year-old woman, a 29-year-old woman, and a 51-year-old man. four cases are thought to have occurred in a mountain area while one occurred in a city garden. none were accompanied with severe systemic symptoms or deuteropathies. the parasites were identified as the adult female tick ixodes ovatus neumann (3 cases) and ixodes nipponensis kitaoka et saito (2 cases), which are commonly distributed in japan.197615633965
detection of dna of 'candidatus mycoplasma haemominutum' and spiroplasma sp. in unfed ticks collected from vegetation in japan.dna fragments of 'candidatus mycoplasma haemominutum', a feline heamobartonella pathogen, were detected from unfed ixodes ovatus collected from vegetation in hokkaido, fukushima and yamaguchi prefectures, and unfed haemaphysalis flava in yamaguchi prefecture. this finding suggests that ixodid tick is a possible vector of 'c. mycoplasma haemominutum'. spiroplasma dna was also detected from unfed i. ovatus in hokkaido, fukushima and yamaguchi prefectures. the analysis of nucleotides sequence sugge ...200516397391
fatal recall responses mediated by cd8 t cells during intracellular bacterial challenge infection.the roles(s) of cd8 t cells during infections by intracellular bacteria that reside in host cell endocytic compartments are not well understood. our previous studies in a mouse model of human monocytotropic ehrlichiosis indicated that cd8 t cells are not essential for immunity. however, we have observed an unexpected role for these cells during challenge infection. although immunocompetent mice cleared a primary low-dose (nonfatal) ixodes ovatus ehrlichia infection, a secondary low-dose challeng ...200616982903
parasite species associated with wild plateau pika (ochotona curzoniae) in southeastern qinghai province, china.a survey was conducted to determine the prevalence and seasonal abundance of egg, larval, and adult stages of helminths; oocyts of protozoans; and ectoparasites of plateau pikas (ochotona curzoniae) in seven areas of southeastern qinghai province, china, during august 2006 and may 2007. fecal samples collected from 430 plateau pikas were examined by the modified mcmaster technique, which revealed that 83% of the samples contained eggs from two or more helminth species. mean fecal egg counts were ...200919395738
relative importance of t-cell subsets in monocytotropic ehrlichiosis: a novel effector mechanism involved in ehrlichia-induced immunopathology in murine ehrlichiosis.infection with gram-negative monocytotropic ehrlichia strains results in a fatal toxic shock-like syndrome characterized by a decreased number of ehrlichia-specific cd4(+) th1 cells, the expansion of tumor necrosis factor alpha (tnf-alpha)-producing cd8(+) t cells, and the systemic overproduction of interleukin-10 (il-10) and tnf-alpha. here, we investigated the role of cd4(+) and cd8(+) t cells in immunity to ehrlichia and the pathogenesis of fatal ehrlichiosis caused by infection with low- and ...200717562770
susceptibility and resistance to monocytic ehrlichiosis in the address the role of cellular immunity during ehrlichia infection, we have utilized a model of monocytic ehrlichiosis that results from infection of mice by ixodes ovatus ehrlichia (ioe). although ehrlichiosis in humans is largely a disease of immunocompromised individuals, the use of the ioe model has allowed us to identify factors required for host defense in normal mice. using a low-dose infection c57bl/6 mouse model, we have demonstrated that host defense requires immune mechanisms involvi ...200516481547
an intradermal environment promotes a protective type-1 response against lethal systemic monocytotropic ehrlichial infection.immune responses against monocytotropic ehrlichiosis during infection with a strain of ehrlichia from ixodes ovatus (ioe) were evaluated using a model that closely reproduces the pathology and immunity associated with tick-transmitted human monocytotropic ehrlichiosis. c57bl/6 mice were inoculated intradermally or intraperitoneally with high-dose highly virulent ioe or intraperitoneally with mildly virulent ehrlichia muris. intradermal (i.d.) infection with ioe established mild, self-limited dis ...200616861674
tick-borne rickettsial pathogens in ticks and small mammals in order to investigate the prevalence of tick-borne infectious agents among ticks, ticks comprising five species from two genera (hemaphysalis spp. and ixodes spp.) were screened using molecular techniques. ticks (3,135) were collected from small wild-caught mammals or by dragging/flagging in the republic of korea (rok) and were pooled into a total of 1,638 samples (1 to 27 ticks per pool). from the 1,638 tick samples, species-specific fragments of anaplasma phagocytophilum (1 sample), anaplasm ...200616957192
rickettsia asiatica sp. nov., isolated in japan.the characterization of a novel rickettsia species, first isolated from ixodes ovatus ticks in japan in 1993, is described for which the name rickettsia asiatica sp. nov. is proposed. using multilocus sequence comparison, five rickettsial isolates from i. ovatus collected at various locations in japan were found to be identical but belonged to a novel species. serotyping also demonstrated this rickettsia to be distinct from previously described rickettsia species. the type strain of rickettsia a ...200617012563
animal model of fatal human monocytotropic ehrlichiosis.human monocytotropic ehrlichiosis caused by ehrlichia chaffeensis is a life-threatening, tick-borne, emerging infectious disease for which no satisfactory animal model has been developed. strain hf565, an ehrlichial organism closely related to e. chaffeensis isolated from ixodes ovatus ticks in japan, causes fatal infection of mice. c57bl/6 mice became ill on day 7 after inoculation and died on day 9. the liver revealed confluent necrosis, ballooning cell injury, apoptosis, poorly formed granulo ...200111159213
virulence potential of ehrlichia chaffeensis strains of distinct genome sequences.human monocytic ehrlichiosis, one of the most frequent life-threatening tick-borne zoonoses, is caused by ehrlichia chaffeensis that lacks endotoxin and peptidoglycan. while sequence polymorphisms in several genes in e. chaffeensis strains have been reported, global genomic divergence and biological differences among strains are unknown. the objectives of the present study were to compare the genome sequences of strains of e. chaffeensis and to examine the virulence potentials of the strains wit ...200717438035
host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, ehrlichia canis.the ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. historically, advances in tick-borne dise ...200818963493
human ehrlichiosis and anaplasmosis.human ehrlichiosis and anaplasmosis are acute febrile tick-borne diseases caused by various members of the genera ehrlichia and anaplasma (anaplasmataceae). human monocytotropic ehrlichiosis has become one of the most prevalent life-threatening tick-borne disease in the united states. ehrlichiosis and anaplasmosis are becoming more frequently diagnosed as the cause of human infections, as animal reservoirs and tick vectors have increased in number and humans have inhabited areas where reservoir ...201020513551
cd4 t-cell epitopes associated with protective immunity induced following vaccination of mice with an ehrlichial variable outer membrane protein.the ehrlichiae express variable outer membrane proteins (omps) that play important roles in both pathogenesis and host defense. previous studies revealed that omps are immunodominant b-cell antigens and that passive transfer of anti-omp antibodies can protect scid mice from fatal ehrlichial infection. in this study, we used a model of fatal monocytotropic ehrlichiosis caused by ehrlichia bacteria from ixodes ovatus (ioe) to determine whether omp immunization could generate protective immunity in ...200717698576
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