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assessment of decorin-binding protein a to the infectivity of borrelia burgdorferi in the murine models of needle and tick infection.decorin-binding proteins (dbps) a and b of borrelia burgdorferi, the agent of lyme disease, are surface-exposed lipoproteins that presumably bind to the extracellular matrix proteoglycan, decorin. b. burgdorferi infects various tissues including the bladder, heart, joints, skin and the central nervous system, and the ability of b. burgdorferi to bind decorin has been hypothesized to be important for this disseminatory pathogenic strategy.200818507835
gene silencing in phlebotomine sand flies: xanthine dehydrogenase knock down by dsrna microinjections.lutzomyia longipalpis are vectors of medically important visceral leishmaniasis in south america. blood-fed adult females digest large amounts of protein, and xanthine dehydrogenase is thought to be a key enzyme involved in protein catabolism through the production of urate. large amounts of heme are also released during digestion with potentially damaging consequences, as heme can generate oxygen radicals that damage lipids, proteins and nucleic acids. however, urate is an antioxidant that may ...200818510977
pattern of proinflammatory cytokine induction in raw264.7 mouse macrophages is identical for virulent and attenuated borrelia burgdorferi.lyme disease pathogenesis results from a complex interaction between borrelia burgdorferi and the host immune system. the intensity and nature of the inflammatory response of host immune cells to b. burgdorferi may be a determining factor in disease progression. gene array analysis was used to examine the expression of genes encoding cytokines, chemokines, and related factors in the joint tissue of infected c3h/hej mice and in a murine macrophage-like cell line in response to a disseminating or ...200818523297
intracellular infection of tick cell lines by the entomopathogenic fungus metarhizium anisopliae.several fungal pathogens are able to enter and persist within eukaryotic cells as part of their infectious life cycle. metarhizium anisopliae is a saprophytic entomopathogenic fungus virulent towards numerous tick species, including those within the genera ixodes and amblyomma. infection of the target organism by this fungus proceeds via several steps, including adhesion and penetration of the host cuticle, proliferation within tissues and the haemolymph, and eventual eruption through the host c ...200818524924
estimating populations of adult ixodes scapularis in mississippi using a sequential bayesian algorithm.a sequential bayesian algorithm and accompanying computer program were developed and validated to estimate population numbers of adult blacklegged tick, ixodes scapularis say, using mark-release-recapture methodology in field plots in central mississippi. in fieldwork, data taken in february 2005 in a 1-ha plot yielded an estimate of 317 adult i. scapularis per ha data from another field plot in 2006, 3 km away, yielded an estimate of 280 adult i. scapularis per ha the number of ticks collected ...200818533452
borrelia burgdorferi sensu stricto is clonal in patients with early lyme borreliosis.lyme borreliosis, the most commonly reported vector-borne disease in north america, is caused by the spirochete borrelia burgdorferi. given the extensive genetic polymorphism of b. burgdorferi, elucidation of the population genetic structure of the bacterium in clinical samples may be relevant for understanding disease pathogenesis and may have applicability for the development of diagnostic tests and vaccine preparations. in this investigation, the genetic polymorphism of the 16s-23s rrna (rrs- ...200818539816
essential role of the response regulator rrp2 in the infectious cycle of borrelia burgdorferi.alteration of surface lipoprotein profiles is a key strategy that the lyme disease pathogen, borrelia burgdorferi, has evolved to be maintained within its enzootic cycle between arthropods and mammals. accumulated evidence indicates that the central regulatory pathway controlling differential gene expression by b. burgdorferi is the rpon-rpos pathway (the sigma(54)-sigma(s) sigma factor cascade). it was previously shown that activation of the rpon-rpos pathway is controlled by rrp2, a two-compon ...200818573895
novel peptide marker corresponding to salivary protein gsg6 potentially identifies exposure to anopheles bites.in order to improve malaria control, and under the aegis of who recommendations, many efforts are being devoted to developing new tools for identifying geographic areas with high risk of parasite transmission. evaluation of the human antibody response to arthropod salivary proteins could be an epidemiological indicator of exposure to vector bites, and therefore to risk of pathogen transmission. in the case of malaria, which is transmitted only by anopheline mosquitoes, maximal specificity could ...200818575604
comparison of the spirochete borrelia burgdorferi s. l. isolated from the tick ixodes scapularis in southeastern and northeastern united states.thirty-five strains of the lyme disease spirochete borrelia burgdorferi sensu lato (b. burgdorferi s. l.) were isolated from the blacklegged tick vector ixodes scapularis in south carolina, georgia, florida, and rhode island. they were characterized by pcr-restriction fragment length polymorphism (rflp) analysis of rrf (5s)-rrl (23s) intergenic spacer amplicons. pcr-rflp analysis indicated that the strains represented at least 3 genospecies (including a possible novel genospecies) and 4 differen ...200818576863
expressed sequence tags from peromyscus testis and placenta tissue: analysis, annotation, and utility for mapping.mice of the genus peromyscus are found in nearly every habitat from alaska to central america and from the atlantic to the pacific. they provide an evolutionary outgroup to the mus/rattus lineage and serve as an intermediary between that lineage and humans. although peromyscus has been studied extensively under both field and laboratory conditions, research has been limited by the lack of molecular resources. genes associated with reproduction typically evolve rapidly and thus are excellent sour ...200818577228
transmission of bartonella henselae by ixodes ricinus.bartonella spp. are facultative intracellular bacteria associated with several emerging diseases in humans and animals. b. henselae causes cat-scratch disease and is increasingly associated with several other syndromes, particularly ocular infections and endocarditis. cats are the main reservoir for b. henselae and the bacteria are transmitted to cats by cat fleas. however, new potential vectors are suspected of transmitting b. henselae, in particular, ixodes ricinus, the most abundant ixodid ti ...200818598628
wide distribution of a high-virulence borrelia burgdorferi clone in europe and north america.the a and b clones of borrelia burgdorferi sensu stricto, distinguished by outer surface protein c (ospc) gene sequences, are commonly associated with disseminated lyme disease. to resolve phylogenetic relationships among isolates, we sequenced 68 isolates from europe and north america at 1 chromosomal locus (16s-23s ribosomal rna spacer) and 3 plasmid loci (ospc,dbpa, and bbd14). the ospc-a clone appeared to be highly prevalent on both continents, and isolates of this clone were uniform in dna ...200818598631
growth of tick-borne encephalitis virus (european subtype) in cell lines from vector and non-vector ticks.we undertook a comparative study of the susceptibility of different tick cell lines to infection with the european subtype of tick-borne encephalitis virus (tbev), prototype strain neudoerfl. the growth of tbev was investigated in lines derived from vector ixodes ricinus l. ticks (ire/ctvm18, 19, and 20), as well as non-vector ticks, namely ixodes scapularis say (ide2), boophilus microplus canestrini (bme/ctvm2), hyalomma anatolicum anatolicum koch (hae/ctvm9), rhipicephalus appendiculatus neuma ...200818602711
a survey for infection with dirofilaria immitis, ehrlichia canis, borrelia burgdorferi, and babesia canis in feral and client-owned dogs in the turks and caicos islands, british west indies.the frequency of infection with dirofilaria immitis and babesia canis and seropositivity to ehrlichia canis and borrelia burgdorferi in feral and client-owned dogs was determined. feral dogs were 14.8 and 11.2 times more likely to be seropositive to d. immitis and e. canis, respectively, than were client-owned dogs. none of the dogs tested positive for b. burgdorferi or b. canis.200818624070
transcriptome analysis of loxosceles laeta (araneae, sicariidae) spider venomous gland using expressed sequence tags.the bite of spiders belonging to the genus loxosceles can induce a variety of clinical symptoms, including dermonecrosis, thrombosis, vascular leakage, haemolysis, and persistent inflammation. in order to examine the transcripts expressed in venom gland of loxosceles laeta spider and to unveil the potential of its products on cellular structure and functional aspects, we generated 3,008 expressed sequence tags (ests) from a cdna library.200818547439
prevention of lyme disease and other tick-borne infections.prevention is the best method for avoiding potentially serious complications of lyme and other tick-borne diseases. in this article, we discuss preventative measures that can be used by individuals or communities. among the topics discussed are personal protective measures, tick reduction, reservoir reduction, and vaccination. additionally, new preventative measures that are in development-including new lyme disease vaccines, antitick vaccines, and reservoir-targeted vaccination-are discussed.200818755380
salivating for knowledge: potential pharmacological agents in tick saliva. 200818271624
competitive exclusion between piroplasmosis and anaplasmosis agents within cattle. 200818225951
role of migratory birds in introduction and range expansion of ixodes scapularis ticks and of borrelia burgdorferi and anaplasma phagocytophilum in canada.during the spring in 2005 and 2006, 39,095 northward-migrating land birds were captured at 12 bird observatories in eastern canada to investigate the role of migratory birds in northward range expansion of lyme borreliosis, human granulocytic anaplasmosis, and their tick vector, ixodes scapularis. the prevalence of birds carrying i. scapularis ticks (mostly nymphs) was 0.35% (95% confidence interval [ci] = 0.30 to 0.42), but a nested study by experienced observers suggested a more realistic infe ...200818245258
clustering of genetically defined allele classes in the caenorhabditis elegans daf-2 insulin/igf-1 receptor.the daf-2 insulin/igf-1 receptor regulates development, metabolism, and aging in the nematode caenorhabditis elegans. however, complex differences among daf-2 alleles complicate analysis of this gene. we have employed epistasis analysis, transcript profile analysis, mutant sequence analysis, and homology modeling of mutant receptors to understand this complexity. we define an allelic series of nonconditional daf-2 mutants, including nonsense and deletion alleles, and a putative null allele, m65. ...200818245374
lyme borreliosis spirochete erp proteins, their known host ligands, and potential roles in mammalian infection.lyme borreliae naturally maintain numerous distinct dna elements of the cp32 family, each of which carries a mono- or bicistronic erp locus. the encoded erp proteins are surface-exposed outer membrane lipoproteins that are produced at high levels during mammalian infection but largely repressed during colonization of vector ticks. recent studies have revealed that some erp proteins can serve as bacterial adhesins, binding host proteins such as the complement regulator factor h and the extracellu ...200818248770
evolution of insect proteomes: insights into synapse organization and synaptic vesicle life cycle.the molecular components in synapses that are essential to the life cycle of synaptic vesicles are well characterized. nonetheless, many aspects of synaptic processes, in particular how they relate to complex behaviour, remain elusive. the genomes of flies, mosquitoes, the honeybee and the beetle are now fully sequenced and span an evolutionary breadth of about 350 million years; this provides a unique opportunity to conduct a comparative genomics study of the synapse.200818257909
blood coagulation, inflammation, and malaria.malaria remains a highly prevalent disease in more than 90 countries and accounts for at least 1 million deaths every year. plasmodium falciparum infection is often associated with a procoagulant tonus characterized by thrombocytopenia and activation of the coagulation cascade and fibrinolytic system; however, bleeding and hemorrhage are uncommon events, suggesting that a compensated state of blood coagulation activation occurs in malaria. this article (i) reviews the literature related to blood ...200818260002
rapid identification of known and new rna viruses from animal tissues.viral surveillance programs or diagnostic labs occasionally obtain infectious samples that fail to be typed by available cell culture, serological, or nucleic acid tests. five such samples, originating from insect pools, skunk brain, human feces and sewer effluent, collected between 1955 and 1980, resulted in pathology when inoculated into suckling mice. in this study, sequence-independent amplification of partially purified viral nucleic acids and small scale shotgun sequencing was used on mous ...200818818738
relative importance of ixodes ricinus and ixodes trianguliceps as vectors for anaplasma phagocytophilum and babesia microti in field vole (microtus agrestis) populations.the importance of ixodes ricinus in the transmission of tick-borne pathogens is well recognized in the united kingdom and across europe. however, the role of coexisting ixodes species, such as the widely distributed species ixodes trianguliceps, as alternative vectors for these pathogens has received little attention. this study aimed to assess the relative importance of i. ricinus and i. trianguliceps in the transmission of anaplasma phagocytophilum and babesia microti among united kingdom fiel ...200818820068
identification of genetic determinants of a tick-borne flavivirus associated with host-specific adaptation and pathogenicity.tick-borne flaviviruses are maintained in nature in an enzootic cycle involving a tick vector and a vertebrate host. thus, the virus replicates in two disparate hosts, each providing selective pressures that can influence virus replication and pathogenicity. to identify viral determinants associated with replication in the individual hosts, plaque purified langat virus (tp21pp) was adapted to growth in mouse or tick cell lines to generate two virus variants, mnbp20 and isep20, respectively. viru ...200818823640
ability of 4-poster passive topical treatment devices for deer to sustain low population levels of ixodes scapularis (acari: ixodidae) after integrated tick management in a residential landscape.in a recent study, the combined use of 4-posters and maxforce tms bait boxes along with a barrier application of deltamethrin resulted in accelerated control of ixodes scapularis say by sequentially attacking each postembryonic life stage. we report the results of a follow-up study to test the ability of 4-posters used alone to sustain the high levels of control achieved through the integrated tick management (itm) approach after withdrawal of the bait boxes. in the first year after withdrawal, ...200818826033
surveillance for lyme disease--united states, 1992-2006.lyme disease is a multisystem disease that occurs in north america, europe, and asia. in the united states, the etiologic agent is borrelia burgdorferi sensu stricto, a spirochete transmitted to humans by infected ixodes scapularis and i. pacificus ticks. the majority of patients with lyme disease develop a characteristic rash, erythema migrans (em), accompanied by symptoms of fever, malaise, fatigue, headache, myalgia, or arthralgia. other manifestations of infection can include arthritis, card ...200818830214
interaction of the lyme disease spirochete borrelia burgdorferi with brain parenchyma elicits inflammatory mediators from glial cells as well as glial and neuronal apoptosis.lyme neuroborreliosis, caused by the spirochete borrelia burgdorferi, often manifests by causing neurocognitive deficits. as a possible mechanism for lyme neuroborreliosis, we hypothesized that b. burgdorferi induces the production of inflammatory mediators in the central nervous system with concomitant neuronal and/or glial apoptosis. to test our hypothesis, we constructed an ex vivo model that consisted of freshly collected slices from brain cortex of a rhesus macaque and allowed live b. burgd ...200818832582
cutting edge: immunity against a "silent" salivary antigen of the lyme vector ixodes scapularis impairs its ability to feed.ixodes scapularis ticks transmit the lyme disease agent in the united states. although strong antitick immunity mediates tick rejection by certain vertebrates, only a few ags have been molecularly characterized. we show that guinea pig vaccination against a secreted tick salivary immunomodulator, sialostatin l2, can lead to decreased feeding ability of i. scapularis nymphs. increased rejection rate, prolonged feeding time, and apparent signs of inflammation were observed for nymphs attached to v ...200818832673
identifying the reservoir hosts of the lyme disease spirochete borrelia burgdorferi in california: the role of the western gray squirrel (sciurus griseus).we investigated the role of the western gray squirrel (sciurus griseus) as a reservoir host of the lyme disease spirochete borrelia burgdorferi. a survey of 222 western gray squirrels in california showed an overall prevalence of b. burgdorferi infection of 30%, although at a county level, prevalence of infection ranged from 0% to 50% by polymerase chain reaction. laboratory trials with wild-caught western gray squirrels indicated that squirrels were competent reservoir hosts of the lyme disease ...200818840740
the pathogenesis of lyme neuroborreliosis: from infection to inflammation.this review describes the current knowledge of the pathogenesis of acute lyme neuroborreliosis (lnb), from invasion to inflammation of the central nervous system. borrelia burgdorferi (b.b.) enters the host through a tick bite on the skin and may disseminate from there to secondary organs, including the central nervous system. to achieve this, b.b. first has to evade the hostile immune system. in a second step, the borrelia have to reach the central nervous system and cross the blood-brain barri ...200818097481
borrelia burgdorferi complement regulator-acquiring surface protein 2 (cspz) as a serological marker of human lyme disease.serological diagnosis of lyme disease may be complicated by antigenic differences between infecting organisms and those used as test references. accordingly, it would be helpful to include antigens whose sequences are well conserved by a broad range of lyme disease spirochetes. in the present study, line blot analyses were performed using recombinant complement regulator-acquiring surface protein 2 (bbcrasp-2) from borrelia burgdorferi sensu stricto strain b31 and serum samples from human lyme d ...200818160620
the ixodes scapularis salivary protein, salp15, prevents the association of hiv-1 gp120 and cd4.ixodes scapularis salivary protein, salp15, inhibits cd4(+) t cell activation by binding to the most-extracellular domains of the cd4 molecule, potentially overlapping with the gp120-binding region. we now show that salp15 inhibits the interaction of gp120 and cd4. furthermore, salp15 prevents syncytia formation between hl2/3 (a stable hela cell line expressing the envelope protein) and cd4-expressing cells. salp15 prevented gp120-cd4 interaction at least partially through its direct interaction ...200818162176
borrelia burgdorferi complement regulator-acquiring surface proteins (bbcrasps): expression patterns during the mammal-tick infection cycle.host complement is widely distributed throughout mammalian body fluids and can be activated immediately as part of the first line of defense against invading pathogens. the agent of lyme disease, borrelia burgdorferi sensu lato (s.l.), is naturally resistant to that innate immune defense system of its hosts. one resistance mechanism appears to involve binding fluid-phase regulators of complement to distinct borrelial outer surface molecules known as crasps (complement regulator acquiring surface ...200818165150
borrelia burgdorferi basic membrane proteins a and b participate in the genesis of lyme arthritis.lyme arthritis results from colonization of joints by borrelia burgdorferi and the ensuing host response. using gene array-based differential analysis of b. burgdorferi gene expression and quantitative reverse trancription-polymerase chain reaction, we identified two paralogous spirochete genes, bmpa and bmpb, that are preferentially up-regulated in mouse joints compared with other organs. transfer of affinity-purified antibodies against either bmpa or bmpb into b. burgdorferi-infected mice sele ...200818166585
variability and action mechanism of a family of anticomplement proteins in ixodes ricinus.ticks are blood feeding arachnids that characteristically take a long blood meal. they must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. this is achieved by expressing batteries of salivary proteins coded by multigene families.200818167559
the midgut transcriptome of lutzomyia longipalpis: comparative analysis of cdna libraries from sugar-fed, blood-fed, post-digested and leishmania infantum chagasi-infected sand flies.in the life cycle of leishmania within the alimentary canal of sand flies the parasites have to survive the hostile environment of blood meal digestion, escape the blood bolus and attach to the midgut epithelium before differentiating into the infective metacyclic stages. the molecular interactions between the leishmania parasites and the gut of the sand fly are poorly understood. in the present work we sequenced five cdna libraries constructed from midgut tissue from the sand fly lutzomyia long ...200818194529
complement evasion by human pathogens.the human immune system has developed an elaborate network of cascades for dealing with microbial intruders. owing to its ability to rapidly recognize and eliminate microorganisms, the complement system is an essential and efficient component of this machinery. however, many pathogenic organisms have found ways to escape the attack of complement through a range of different mechanisms. recent discoveries in this field have provided important insights into these processes on a molecular level. th ...200818197169
effect of electronic laboratory reporting on the burden of lyme disease surveillance--new jersey, 2001-2006.lyme disease (ld) is a vector-borne illness caused by the spirochete borrelia burgdorferi and transmitted in the united states by blacklegged ticks (ixodes spp.). ld is most commonly found in the northeastern, mid-atlantic, and north-central regions of the united states. in 2005, new jersey reported 38.6 ld cases per 100,000 population, the third-highest incidence in the united states after delaware and connecticut. since 1980, new jersey has mandated that health-care providers and clinical labo ...200818199968
plasmids of the prm/prf family occur in diverse rickettsia species.the recent discoveries of the prf and prm plasmids of rickettsia felis and r. monacensis have contravened the long-held dogma that plasmids are not present in the bacterial genus rickettsia (rickettsiales; rickettsiaceae). we report the existence of plasmids in r. helvetica, r. peacockii, r. amblyommii, and r. massiliae isolates from ixodid ticks and in an r. hoogstraalii isolate from an argasid tick. r. peacockii and four isolates of r. amblyommii from widely separated geographic locations cont ...200818065613
an insight into the sialome of the soft tick, ornithodorus parkeri.while hard ticks (ixodidae) take several days to feed on their hosts, soft ticks (argasidae) feed faster, usually taking less than 1h per meal. saliva assists in the feeding process by providing a cocktail of anti-hemostatic, anti-inflammatory and immunomodullatory compounds. saliva of hard ticks has been shown to contain several families of genes each having multiple members, while those of soft ticks are relatively unexplored. analysis of the salivary transcriptome of the soft tick ornithodoru ...200818070662
characterization of anti-hemostatic factors in the argasid, argas monolakensis: implications for the evolution of blood-feeding in the soft tick family.to date, the only anti-hemostatic factors characterized for softs ticks are for ornithodoros moubata and ornithodoros savignyi, ticks that feeds mainly on mammals. this includes thrombin (ornithodorin and savignin), fxa (tap and fxai) and platelet aggregation (disagegin and savignygrin) inhibitors that belong to the bpti-kunitz protein family. this raises the question on how well anti-hemostatic factors will be conserved in other soft tick genera that feeds on other vertebrates such as birds. we ...200818070663
comparative sialomics between hard and soft ticks: implications for the evolution of blood-feeding behavior.ticks evolved various mechanisms to modulate their host's hemostatic and immune defenses. differences in the anti-hemostatic repertoires suggest that hard and soft ticks evolved anti-hemostatic mechanisms independently, but raise questions on the conservation of salivary gland proteins in the ancestral tick lineage. to address this issue, the sialome (salivary gland secretory proteome) from the soft tick, argas monolakensis, was determined by proteomic analysis and cdna library construction of s ...200818070664
conspicuous impacts of inconspicuous hosts on the lyme disease epidemic.emerging zoonotic pathogens are a constant threat to human health throughout the world. control strategies to protect public health regularly fail, due in part to the tendency to focus on a single host species assumed to be the primary reservoir for a pathogen. here, we present evidence that a diverse set of species can play an important role in determining disease risk to humans using lyme disease as a model. host-targeted public health strategies to control the lyme disease epidemic in north a ...200818029304
ixolaris binding to factor x reveals a precursor state of factor xa heparin-binding exosite.ixolaris is a two-kunitz tick salivary gland tissue factor pathway inhibitor (tfpi). in contrast to human tfpi, ixolaris specifically binds to factor xa (fxa) heparin-binding exosite (hbe). in addition, ixolaris interacts with zymogen fx. in the present work we characterized the interaction of ixolaris with human fx quantitatively, and identified a precursor state of the heparin-binding exosite (proexosite, hbpe) as the ixolaris-binding site on the zymogen. gel-filtration chromatography demonstr ...200818042685
conformational rearrangement within the soluble domains of the cd4 receptor is ligand-specific.ligand binding induces shape changes within the four modular ectodomains (d1-d4) of the cd4 receptor, an important receptor in immune signaling. small angle x-ray scattering (saxs) on both a two-domain and a four-domain construct of the soluble cd4 (scd4) is consistent with known crystal structures demonstrating a bilobal and a semi-extended tetralobal z conformation in solution, respectively. detection of conformational changes within scd4 as a result of ligand binding was followed by saxs on s ...200818045872
bartonella sp. bacteremia in patients with neurological and neurocognitive dysfunction.we detected infection with a bartonella species (b. henselae or b. vinsonii subsp. berkhoffii) in blood samples from six immunocompetent patients who presented with a chronic neurological or neurocognitive syndrome including seizures, ataxia, memory loss, and/or tremors. each of these patients had substantial animal contact or recent arthropod exposure as a potential risk factor for bartonella infection. additional studies should be performed to clarify the potential role of bartonella spp. as a ...200818632903
oral immunization with recombinant lactobacillus plantarum induces a protective immune response in mice with lyme disease.mucosal immunization is advantageous over other routes of antigen delivery because it can induce both mucosal and systemic immune responses. our goal was to develop a mucosal delivery vehicle based on bacteria generally regarded as safe, such as lactobacillus spp. in this study, we used the lyme disease mouse model as a proof of concept. we demonstrate that an oral vaccine based on live recombinant lactobacillus plantarum protects mice from tick-transmitted borrelia burgdorferi infection. our me ...200818632920
projected effects of climate change on tick phenology and fitness of pathogens transmitted by the north american tick ixodes scapularis.ixodes scapularis is the principal tick vector of the lyme borreliosis agent borrelia burgdorferi and other tick-borne zoonoses in northeastern north america. the degree of seasonal synchrony of nymphal and larval ticks may be important in influencing the basic reproductive number of the pathogens transmitted by i. scapularis. because the seasonal phenology of tick vectors is partly controlled by ambient temperature, climate and climate change could shape the population biology of tick-borne pat ...200818634803
relapsing fever spirochetes retain infectivity after prolonged in vitro cultivation.borrelia hermsii and borrelia burgdorferi, two closely related spirochetes, are the etiological agents of tick-borne relapsing fever and lyme disease, respectively. previous studies have shown the loss of infectivity of b. burgdorferi is associated with in vitro cultivation. this diminished infectivity of b. burgdorferi has occurred as early as three in vitro passages, and the loss of plasmids have been observed with these less virulent to noninfective cultures. the effects of long-term in vitro ...200818637723
north american encephalitic arboviruses.arboviruses continue to be a major cause of encephalitis in north america, and west nile virus neuroinvasive disease is now the dominant cause of encephalitis. transmission to humans of north american arboviruses occurs by infected mosquitoes or ticks. most infections are asymptomatic or produce a flulike illness. rapid serum or cerebrospinal fluid igm antibody capture elisa assays are available to diagnosis the acute infection for all north american arboviruses. unfortunately, no antiviral drug ...200818657724
differential expression of a putative card-like transcriptional regulator, ltpa, in borrelia burgdorferi.the availability of microbial genome information has provided a fruitful opportunity for studying regulatory networks in a variety of pathogenic bacteria. in an initial effort to elucidate regulatory networks potentially involved in differential gene expression by the lyme disease pathogen borrelia burgdorferi, we have been investigating the functions and regulation of putative transcriptional regulatory factors predicted to be encoded within the b. burgdorferi genome. herein we report the regul ...200818663002
whole genome transcription profiling of anaplasma phagocytophilum in human and tick host cells by tiling array analysis.anaplasma phagocytophilum (ap) is an obligate intracellular bacterium and the agent of human granulocytic anaplasmosis, an emerging tick-borne disease. ap alternately infects ticks and mammals and a variety of cell types within each. understanding the biology behind such versatile cellular parasitism may be derived through the use of tiling microarrays to establish high resolution, genome-wide transcription profiles of the organism as it infects cell lines representative of its life cycle (tick; ...200818671858
evidence of the role of tick subolesin in gene expression.subolesin is an evolutionary conserved protein that was discovered recently in ixodes scapularis as a tick protective antigen and has a role in tick blood digestion, reproduction and development. in other organisms, subolesin orthologs may be involved in the control of developmental processes. because of the profound effect of subolesin knockdown in ticks and other organisms, we hypothesized that subolesin plays a role in gene expression, and therefore affects multiple cellular processes. the ob ...200818673577
a novel clade of cysteinyl leukotriene scavengers in soft ticks.inflammation is an important vertebrate defense mechanism against ecto-parasites for which ticks have evolved numerous mechanisms of modulation. am-33 and tsgp4, related lipocalins from the soft ticks argas monolakensis and ornithodoros savignyi bind cysteinyl leukotrienes with high affinity as measured by isothermal titration calorimetry. this was confirmed in a smooth muscle bioassay that measured contraction of guinea pig ileum induced by leukotriene c4 where both proteins inhibited contracti ...200818675910
identification of residual blood proteins in ticks by mass spectrometry proteomics.mass spectrometry-based proteomics of individual ticks demonstrated persistence of mammalian host blood components, including alpha- and beta-globin chains, histones, and mitochondrial enzymes, in ixodes scapularis and amblyomma americanum ticks for months after molting. residual host proteins may identify sources of infection for ticks.200818680654
function, mechanism and evolution of the moubatin-clade of soft tick lipocalins.the "moubatin-clade" of soft tick lipocalins, although monophyletic, shows clear signs of paralogy as indicated by the various functions associated with this protein family. this includes anti-platelet (moubatin), anti-complement (omci) and toxic (tsgp2) activities in the vertebrate host. in order to understand the evolution of function and how it relates to the various paralogs in this clade, we characterized a number of different proteins in regard to undefined function and mechanism. by utili ...200818694828
rapid introduction of lyme disease spirochete, borrelia burgdorferi sensu stricto, in ixodes scapularis (acari: ixodidae) established at turkey point provincial park, ontario, canada.borrelia burgdorferi sensu stricto (s.s.) was isolated from questing adult ixodes scapularis say ticks collected from turkey point provincial park (tppp), ontario, canada during 2005-2006. dna from ten (67%) of 15 pools of ticks was confirmed positive for b. burgdorferi s.s. using polymerase chain reaction (pcr) by targeting the rrf (5s)-rrl (23s) intergenic spacer region and ospa genes. this significant infection rate indicates an accelerated development of b. burgdorferi s.s. in tppp, because ...200818697308
total, membrane, and immunogenic proteomes of macrophage- and tick cell-derived ehrlichia chaffeensis evaluated by liquid chromatography-tandem mass spectrometry and maldi-tof methods.ehrlichia chaffeensis, a tick-transmitted rickettsial, is the causative agent of human monocytic ehrlichiosis. to examine protein expression patterns, we analyzed total, membrane, and immunogenic proteomes of e. chaffeensis originating from macrophage and tick cell cultures. total proteins resolved by one-dimensional gel electrophoresis and subjected to liquid chromatography-electrospray ionization ion trap mass spectrometry allowed identification of 134 and 116 proteins from macrophage- and tic ...200818710870
borrelia burgdorferi complement regulator-acquiring surface protein 2 does not contribute to complement resistance or host infectivity.borrelia burgdorferi, the pathogen of lyme disease, cycles in nature through ixodes ticks and mammalian hosts. at least five complement regulator-acquiring surface proteins (bbcrasps) are produced by b. burgdorferi, which are thought to assist spirochetes in host immune evasion. recent studies established that bbcrasp-2 is preferentially expressed in mammals, and elicits robust antibody response in infected hosts, including humans. we show that bbcrasp-2 is ubiquitously expressed in diverse muri ...200818714378
evidence of the importance of host habitat use in predicting the dilution effect of wild boar for deer exposure to anaplasma spp.foci of tick-borne pathogens occur at fine spatial scales, and depend upon a complex arrangement of factors involving climate, host abundance and landscape composition. it has been proposed that the presence of hosts that support tick feeding but not pathogen multiplication may dilute the transmission of the pathogen. however, models need to consider the spatial component to adequately explain how hosts, ticks and pathogens are distributed into the landscape. in this study, a novel, lattice-deri ...200818714379
prolonged efficacy of ir3535 repellents against mosquitoes and blacklegged ticks in north america.here i report the first findings of consistently high, long-duration efficacy of ir3535 (ethyl butyl acetyl aminopropionate) formulations in the united states. i tested novel, controlled-release formulations of ir3535, at 10% in lotion and at 20% in pump spray and aerosol, against mosquitoes in the field and blacklegged ticks in the laboratory. these were also the first studies to be conducted under the authority of the u.s. environmental protection agency's human studies rule of 2006, and the p ...200818714871
transmission dynamics of borrelia burgdorferi s.s. during the key third day of feeding by nymphal ixodes scapularis (acari: ixodidae).nymphal ixodes scapularis say are the principal vectors of lyme disease spirochetes (borrelia burgdorferi sensu stricto) in the eastern united states. physicians frequently face the decision of whether or not to administer prophylactic antibiotics to human tick bite victims in lyme disease endemic regions, based on the overall probability that such bites will result in infection with b. burgdorferi s.s. we evaluated the transmission dynamics of b. burgdorferi s.s. during the key third day of nym ...200818714875
establishment of a large semi-field system for experimental study of african malaria vector ecology and control in tanzania.medical entomologists increasingly recognize that the ability to make inferences between laboratory experiments of vector biology and epidemiological trends observed in the field is hindered by a conceptual and methodological gap occurring between these approaches which prevents hypothesis-driven empirical research from being conducted on relatively large and environmentally realistic scales. the development of semi-field systems (sfs) has been proposed as the best mechanism for bridging this ga ...200818715508
serum antibodies to west nile virus in naturally exposed and vaccinated horses.a polyvalent elisa and plaque reduction neutralization tests (prnts) were used to measure serum antibodies to west nile virus (wnv) in horses naturally exposed to or vaccinated against this flavivirus in connecticut and new york state, usa. relying on a prnt as a 'gold standard', the main objective was to validate a modified elisa containing a recombinant wnv envelope protein antigen. it was also important to assess specificity by testing sera from horses that had other, undiagnosed illnesses. s ...200818719177
transgene expression and silencing in a tick cell line: a model system for functional tick genomics.the genome project of the black legged tick, ixodes scapularis, provides sequence data for testing gene function and regulation in this important pathogen vector. we tested sleeping beauty (sb), a tc1/mariner group transposable element, and cationic lipid-based transfection reagents for delivery and genomic integration of transgenes into i. scapularis cell line ise6. plasmid dna and dsrna were effectively transfected into ise6 cells and they were successfully transformed to express a red fluores ...200818722527
transcriptional up-regulation of disk abalone selenium dependent glutathione peroxidase by h(2)o(2) oxidative stress and vibrio alginolyticus bacterial infection.selenium dependent glutathione peroxidase (se-gpx) belongs to the family of selenoprotein, which acts mainly as an antioxidant in the cellular defence system. we have identified se-gpx full length cdna from disk abalone (haliotis discus discus) designated as abse-gpx. it has a characteristic codon at (223)tga(225) that corresponds to selenocysteine (sec) amino acid as u(75). the full length cdna consists of 675 bp, an open reading frame encoding 225 amino acids. sequence characterization reveale ...200818722791
multiple causes of variable tick burdens on small-mammal hosts.blood meals by blacklegged ticks (ixodes scapularis) on vertebrate hosts serve to transmit the agents of several zoonotic diseases, including lyme disease, human babesiosis, and human granulocytic anaplasmosis, between host and tick. if ticks are aggregated on hosts, a small proportion of hosts may be responsible for most transmission events. therefore, a key element in understanding and controlling the transmission of these pathogens is identifying the group(s) or individuals feeding a dispropo ...200818724736
effect of borrelia burgdorferi genotype on the sensitivity of c6 and 2-tier testing in north american patients with culture-confirmed lyme disease.a potential concern with any serologic test to detect antibodies to borrelia burgdorferi is whether the epitopes incorporated in the test provide sufficient cross-reactivity to detect infection with all of the pathogenic strains of the species. this is a particular concern for the c6 test, which is based on reactivity to a single peptide.200818724824
borrelia burgdorferi lipoprotein bmpa activates pro-inflammatory responses in human synovial cells through a protein moiety.borrelia burgdorferi invasion of mammalian joints results in genesis of lyme arthritis. other than spirochete lipids, existence of protein antigens, which are abundant in joints and participate in b. burgdorferi-induced host inflammatory response, is unknown. here, we report that major products of the b. burgdorferi basic membrane protein (bmp) a/b operon that are induced in murine and human joints, possess inflammatory properties. compared to the wild type b. burgdorferi, an isogenic bmpa/b mut ...200818725314
an insight into the salivary transcriptome and proteome of the soft tick and vector of epizootic bovine abortion, ornithodoros coriaceus.the salivary glands of blood-sucking arthropods contain a redundant 'magic potion' that counteracts their vertebrate host's hemostasis, inflammation, and immunity. we here describe the salivary transcriptome and proteomics (sialome) of the soft tick ornithodoros coriaceus. the resulting analysis helps to consolidate the classification of common proteins found in both soft and hard ticks, such as the lipocalins, kunitz, cystatin, basic tail, hebraein, defensin, til domain, metalloprotease, 5'-nuc ...200818725333
preferential protection of borrelia burgdorferi sensu stricto by a salp15 homologue in ixodes ricinus saliva.ixodes ticks are the main vectors for borrelia burgdorferi sensu lato. in the united states, b. burgdorferi is the sole causative agent of lyme borreliosis and is transmitted by ixodes scapularis. in europe, 3 borrelia species-b. burgdorferi, b. garinii, and b. afzelii-are prevalent, which are transmitted by ixodes ricinus. the i. scapularis salivary protein salp15 has been shown to bind to b. burgdorferi outer surface protein (osp) c, protecting the spirochete from antibody-mediated killing.200818752445
tick-borne relapsing fever.each year, many residents of and visitors to endemic regions of the western united states are exposed to the tick vectors of tick-borne relapsing fever (tbrf), ornithodoros hermsi, ornithodoros turicata, or ornithodoros parkeri. this disease is remarkable because the human host is unaware of the tick bite, usually becomes very ill, may experience an exacerbation of symptoms rather than improvement shortly after beginning appropriate treatment, and, despite often high numbers of the etiologic org ...200818755384
human babesiosis.human babesiosis is an emerging intraerythrocytic infection caused by protozoal parasites transmitted by ixodid ticks. babesiosis is endemic in the northeastern and upper midwestern regions of the united states and is found sporadically in other parts of the united states, europe, asia, africa, and south america. babesial infections range from asymptomatic to severe and occasionally are fatal. specific laboratory diagnosis of babesial infection is made by morphologic examination of giemsa-staine ...200818755385
tularemia in a park, philadelphia, pennsylvania. 200818760026
laboratory maintenance of ehrlichia chaffeensis and ehrlichia canis and recovery of organisms for molecular biology and proteomics studies.tick-borne illnesses are emerging as a major concern for human health in recent years. these include the human monocytic ehrlichiosis caused by the amblyomma americanum tick-transmitted bacterium, ehrlichia chaffeensis; human ewingii ehrlichiosis caused by ehrlichia ewingii (also transmitted by a. americanum ticks); and human granulocytic anaplasmosis caused by the ixodes scapularis tick-transmitted pathogen, anaplasma phagocytophilum. likewise, tick-borne rickettsial pathogens are also a major ...200818770537
functional characterization and novel rickettsiostatic effects of a kunitz-type serine protease inhibitor from the tick dermacentor variabilis.here we report the novel bacteriostatic function of a five-domain kunitz-type serine protease inhibitor (kpi) from the tick dermacentor variabilis. as ticks feed, they release anticoagulants, anti-inflammatory and immunosuppressive molecules that mediate the formation of the feeding lesion on the mammalian host. a number of kpis have been isolated and characterized from tick salivary gland extracts. interestingly, we observe little d. variabilis kpi gene expression in the salivary gland and abun ...200818779339
outer surface protein a protects lyme disease spirochetes from acquired host immunity in the tick vector.the lyme disease spirochete borrelia burgdorferi alters the expression of outer surface protein (osp) genes as the bacterium cycles between ticks and mammals. ospa is produced as borreliae enter the tick vector and remains a major surface antigen during midgut colonization. to elucidate the role of ospa in the vector, we created an insertional deletion of ospa in strain b31-a3. the ospa mutant infects mice when it is injected intradermally and is acquired by larval ticks fed on these mice, where ...200818779341
borrelia burgdorferi genotype predicts the capacity for hematogenous dissemination during early lyme disease.lyme disease, the most common tickborne disease in the united states, is caused exclusively by borrelia burgdorferi sensu stricto in north america. the present study evaluated the genotypes of >400 clinical isolates of b. burgdorferi recovered from patients from suburban new york city with early lyme disease associated with erythema migrans; it is the largest number of borrelial strains from north america ever to be investigated.200818781866
spatial dynamics of lyme disease: a review.lyme disease (ld), the most frequently reported vector-borne disease in the united states, requires that humans, infected vector ticks, and infected hosts all occur in close spatial proximity. understanding the spatial dynamics of ld requires an understanding of the spatial determinants of each of these organisms. we review the literature on spatial patterns and environmental correlates of human cases of ld and the vector ticks, ixodes scapularis in the northeastern and midwestern united states ...200818787920
in vitro isolation of ehrlichia ruminantium from ovine blood into ixodes scapularis (ide8) cell cultures.four stocks of ehrlichia ruminantium (welgevonden, ball3, nonile and blaauwkrans), the causative agent of heartwater in domestic ruminants, were isolated into ixodes scapularis (ide8) tick cells using the leukocyte fraction of the blood of infected sheep. organisms of two of the e. ruminantium stocks (welgevonden and blaauwkrans) propagated in ide8 cells were also successfully used to infect bovine endothelial cells. all stocks were successfully propagated in ide8 cells using dulbecco's modified ...200818788205
production of outer surface protein a by borrelia burgdorferi during transmission from infected mammals to feeding ticks is insufficient to trigger ospa seroconversion.the lyme disease spirochete, borrelia burgdorferi, produces two outer surface lipoproteins, ospa and ospb, that are essential for colonization of tick vectors. both proteins are highly expressed during transmission from infected mammals to feeding ticks and during colonization of tick midguts, but are repressed when bacteria are transmitted from ticks to mammals. humans and other infected mammals generally do not produce antibodies against either protein, although some lyme disease patients do s ...200818793197
rhipicephalus appendiculatus: characterization of a testis-associated protein.a novel gene coding for rhipicephalus appendiculatus male-specific protein (ramp) was identified in a cdna library constructed from the testis/vas deferens of r. appendiculatus ticks. this gene encodes a secreted protein exclusively expressed in the testis/vas deferens. the putative ramp amino acid sequence contains a signal peptide and has 29% amino acid identity with male-specific is5 gene of ixodes scapularis. gene expression studies revealed that ramp mrna was up-regulated in male ticks duri ...200818796305
suppression of ixodes scapularis (acari: ixodidae) following annual habitat-targeted acaricide applications against fall populations of adults.spring acaricide applications directed against nymphal ixodes scapularis have been shown to be effective, but are perceived by the public as having significant adverse environmental impacts, particularly against nontarget organisms. targeting the adult stage of i. scapularis in the fall would hypothetically result in indirect control of subsequent subadult stages while avoiding other arthropods that are typically inactive during this period. we demonstrate that single fall applications of deltam ...200819181066
lyme arthritis: current concepts and a change in paradigm. 200818003815
evaluation of the recombinant vlse-based liaison chemiluminescence immunoassay for detection of borrelia burgdorferi and diagnosis of lyme disease.recent efforts to improve the serologic diagnosis of lyme disease have included the use of a synthetic peptide (c6) that reproduces the sequence of invariable region 6 of vlse, the variable surface antigen of borrelia burgdorferi. in the present study, the diagnostic performance of diasorin's recombinant vlse-based chemiluminescence immunoassay in 1,947 human serum samples was evaluated. sensitivity was determined using two serum panels from the cdc. for panel i, we observed sensitivities of 68. ...200818945880
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
abrogation of ospab constitutively activates the rrp2-rpon-rpos pathway (sigman-sigmas cascade) in borrelia burgdorferi.molecular mechanisms underlying the reciprocal regulation of the two major surface lipoproteins and virulence factors of borrelia burgdorferi, ospa and ospc, are not fully understood. herein, we report that inactivation of the ospab operon resulted in overproduction of ospc and many other lipoproteins via the constitutive activation of the rrp2-rpon-rpos pathway. complementing the ospab mutant with a wild-type copy of ospa, but not an ospa variant that lacks the lipoprotein signal sequence, rest ...200819019147
fever of unknown origin (fuo) due to babesiosis in a immunocompetent host.fevers of unknown origin (fuos) are defined as prolonged fevers of 101 degrees f or greater lasting 3 or more weeks that remain undiagnosed after comprehensive inpatient/outpatient laboratory testing. tick-borne infections are uncommon causes of fuos. any infectious disease accompanied by prolonged fevers can present as an fuo if the diagnosis is not suspected or if specific laboratory testing is not done to confirm the diagnosis. babesiosis is transmitted by the ixodes scapularis ticks endemic ...200818992633
exploring the mialome of ticks: an annotated catalogue of midgut transcripts from the hard tick, dermacentor variabilis (acari: ixodidae).ticks are obligate blood feeders. the midgut is the first major region of the body where blood and microbes ingested with the blood meal come in contact with the tick's internal tissues. little is known about protein expression in the digestive tract of ticks. in this study, for analysis of global gene expression during tick attachment and feeding, we generated and sequenced 1,679 random transcripts (ests) from cdna libraries from the midguts of female ticks at varying stages of feeding.200819021911
stable prevalence of powassan virus in ixodes scapularis in a northern wisconsin focus.deer tick virus (dtv), a variant of powassan virus (powv), appears to be maintained in nature in an enzootic cycle between ixodes scapularis ticks and small mammals. although powv infection of human beings is rare, a recent report suggests increasing incidence and the possibility that powv may be an emerging tick-borne zoonosis. therefore, we assessed the long-term stability of the powv transmission cycle in northwestern wisconsin. adult i. scapularis and dermacentor variabilis were collected fr ...200819052313
nkt cells prevent chronic joint inflammation after infection with borrelia burgdorferi.borrelia burgdorferi is the etiologic agent of lyme disease, a multisystem inflammatory disorder that principally targets the skin, joints, heart, and nervous system. the role of t lymphocytes in the development of chronic inflammation resulting from b. burgdorferi infection has been controversial. we previously showed that natural killer t (nkt) cells with an invariant (i) tcr alpha chain (inkt cells) recognize glycolipids from b. burgdorferi, but did not establish an in vivo role for inkt cell ...200819060201
ir-lbp, an ixodes ricinus tick salivary ltb4-binding lipocalin, interferes with host neutrophil function.during their blood meal, ticks secrete a wide variety of proteins that can interfere with their host's defense mechanisms. among these proteins, lipocalins play a major role in the modulation of the inflammatory response.200819096526
ixodes ricinus tick lipocalins: identification, cloning, phylogenetic analysis and biochemical characterization.during their blood meal, ticks secrete a wide variety of proteins that interfere with their host's defense mechanisms. among these proteins, lipocalins play a major role in the modulation of the inflammatory response.200819096708
fine-scale phylogeographic structure of borrelia lusitaniae revealed by multilocus sequence typing.borrelia lusitaniae is an old world species of the lyme borreliosis (lb) group of tick-borne spirochetes and prevails mainly in countries around the mediterranean basin. lizards of the family lacertidae have been identified as reservoir hosts of b. lusitaniae. these reptiles are highly structured geographically, indicating limited migration. in order to examine whether host geographic structure shapes the evolution and epidemiology of b. lusitaniae, we analyzed the phylogeographic population str ...200819104655
differential expression of the tick protective antigen subolesin in anaplasma marginale- and a. phagocytophilum-infected host cells.subolesin was recently shown in vaccine and rna interference (rnai) studies to protect against tick infestations and to affect tick feeding, reproduction, and development as well as infection of host cells by anaplasma marginale and a. phagocytophilum. recent experiments provided evidence that infection of both tick and vertebrate host cells with these two pathogens modified gene expression. we therefore hypothesized that infection of host cells with a. marginale and a. phagocytophilum affects e ...200819120168
defining the role of subolesin in tick cell culture by use of rna interference.development of tick vaccines provides new opportunities for control of tick infestations and tick-borne diseases. recently, the tick-protective protein, subolesin, was identified in a cell line derived from ixodes scapularis by expression library immunization and a mouse model of tick infestations. while subolesin was conserved among ixodid tick species, the biological function of this gene is unknown. subolesin expression in ticks was silenced by rna interference (rnai) to provide information o ...200819120170
acinetobacter baumannii invades epithelial cells and outer membrane protein a mediates interactions with epithelial cells.acinetobacter baumannii is a nosocomial pathogen of increasing importance, but the pathogenic mechanism of this microorganism has not been fully explored. this study investigated the potential of a. baumannii to invade epithelial cells and determined the role of a. baumannii outer membrane protein a (abompa) in interactions with epithelial cells.200819068136
comparative analysis of septic injury-inducible genes in phylogenetically distant model organisms of regeneration and stem cell research, the planarian schmidtea mediterranea and the cnidarian hydra vulgaris.the planarian schmidtea mediterranea and the cnidarian hydra vulgaris have emerged as valuable model organisms in regeneration and stem cell research because of their prominent ability to regenerate a complete organism from any small body fragment. under natural conditions wounding may result from predator attacks. these injuries open their innermost to a wide array of microbes present in the environment. therefore, we established the hypothesis that regeneration processes may be linked to or at ...200818439314
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