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Sample records for leptospire leptospira interrogans

  1. Effects of Static Magnetic Field on Growth of Leptospire, Leptospira interrogans serovar canicola: Immunoreactivity and Cell Division

    CERN Document Server

    Triampo, W; Triampo, D; Wong-Ekkabut, J; Tang, I M; Triampo, Wannapong; Doungchawee, Galayanee; Triampo, Darapond; Wong-Ekkabut, Jirasak

    2004-01-01

    The effects of the exposure of the bacterium, Leptospira interrogans serovar canicola to a constant magnetic field with magnetic flux density from a permanent ferrite magnet = 140 mT were studied. Changes in Leptospira cells after their exposure to the field were determined on the basis of changes in their growth behavior and agglutination immunoreactivity with a homologous antiserum using darkfield microscopy together with visual imaging. The data showed that the exposed Leptospira cells have lower densities and lower agglutination immunoreactivity than the unexposed control group. Interestingly, some of the exposed Leptospira cells showed abnormal morphologies such as large lengths. We discussed some of the possible reasons for these observations.

  2. Expression of leptospiral immunoglobulin-like protein by Leptospira interrogans and evaluation of its diagnostic potential in a kinetic ELISA.

    Science.gov (United States)

    Palaniappan, Raghavan U M; Chang, Yung-Fu; Hassan, Fahad; McDonough, Sean P; Pough, Margaret; Barr, Stephen C; Simpson, Kenneth W; Mohammed, Hussni O; Shin, Sang; McDonough, Patrick; Zuerner, Richard L; Qu, Jiaxin; Roe, Bruce

    2004-10-01

    The search for novel antigens suitable for improved vaccines and diagnostic reagents against leptospirosis led to the identification of LigA and LigB. LigA and LigB expression were not detectable at the translation level but were detectable at the transcription level in leptospires grown in vitro. Lig genes were present in pathogenic serovars of Leptospira, but not in non-pathogenic Leptospira biflexa. The conserved and variable regions of LigA and LigB (Con, VarA and VarB) were cloned, expressed and purified as GST-fusion proteins. Purified recombinant LigA and LigB were evaluated for their diagnostic potential in a kinetic ELISA (KELA) using sera from vaccinated and microscopic agglutination test (MAT)-positive dogs. Sera from vaccinated dogs showed reactivity to whole-cell antigens of leptospires but did not show reactivity in the KELA assay with recombinant antigens, suggesting a lack of antibodies to Lig proteins in the vaccinated animals. The diagnostic potential of recombinant Lig antigens in the KELA assay was evaluated by using 67 serum samples with MAT > or =1600, which showed reactivity of 76, 41 and 35% to rConA, rVarA and rVarB, respectively. These findings suggest that recombinant antigen to the conserved region of LigA and LigB can differentiate between vaccinated and naturally infected animals.

  3. Investigation on the presence of leptospires in ovaries of hamsters experimentally infected whith Leptospiras interrogans serovar pomona

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    Claudio Roberto de Almeida Camargo

    1993-12-01

    Full Text Available After inoculating L. interrogans serovar pomona in 75 primiparous hamsters (Mesocricetus auratus, the invasiveness of leptospires into lhe ovaries and lhe ability in causing ovary morphologic alterations were investigated by means of microscopic examination and bacterial isolation. For this purpose, 75 hamsters were inoculated with 0.5 ml of virulent strain containing 30-40 leptospires by the microscopic field and the other 15 hamsters were held as the uninfected controls. Signs and symptoms (prostration, tachypnea, rufled hair, jaundice, and nasal, bucal and perineal hemorrage were detected in all inoculated animals. The animals were killed in the agonic state of the illness, which were done through 4th and 7th day post inoculation. The ovaries were taken asseptically during the necropsies, thoroughly washed using the sterile phosphate buffered saline, in order to eliminate the possible external contamination. The fresh ovary samples were submitted to the dark field direct microscopic examination. After the formalin fixation, the specimens were stained by means of histopathologic techniques using the Levaditi and Hematoxylin Eosin stains. The ovary smears were also examined by the direct fluorescent antibody technique andlhe bacterial isolation was carried out in the Fletcher’s medium. The dark field direct microscopic examination was found tobe less sensitive in demonstrating the presence of leptospiresin the ovaries. In those specimens stained by the Lcvadititechnique, leptospires were visualized in different ovaryinternal structures, involving the interspace, pellucid zone andin the inner ovules. Through the histopathologic examination,typical morphologic alterations resembling acute infiamatoryprocess were found in 57% of ovaries examined.

  4. Leptospira interrogans serotype hardjo in dairy cows

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    Vidić Branka M.

    2003-01-01

    Full Text Available Data on L. hardjo infection of dairy cows in the world pint out its important role in the occurrence of health and economic problem. L. interrogans serotype hardjo has been described as the cause of miscarriages, stillbirts, or the birhs of poorly vital calves, agalactia, mastitis, and low fertility in cows. Two L. hardjo genotypes have been identified in cows, namely, hardjopraitno and hardjobovis. Serological investigations have established a drastic increase in this leptospiral infection in cows. L. hardjo has become adapted to cattle as the primary host, so that an infection is maintained in herds and becomes deeply rooted because of the permanent presence of the source of infection. It was believed that sheep were accidental hosts, but the latest research suggest that they are yet another, transitory, host for maintining this leptospira serotype. L. hardjo is also important from the aspect of human health, especially of persons who are professionally exposed to this infection. L. hardjo infection is detected using serological tests and by proving the presence of leptospira. The medicine of choice in the therapy of leptospiral infections is streptomycin (DSM. Therapy using oxytetracyclines for clinical mastitis was also proven effective. Treatment is most successful in the early stage of the disease. A single dose of streptomycin administered in infected herds reduces the duration period of leptospira excretion through urine, thus preventing the spread of infection thorugh contaminated urine. The basic components of the plan to contain leptospira are the following: serological investigations, sanitary-higiene measures, the elimination of animals which excrete leptospira through urine, therapy, vaccination, quarantine.

  5. Genome features of Leptospira interrogans serovar Copenhageni

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    A.L.T.O. Nascimento

    2004-04-01

    Full Text Available We report novel features of the genome sequence of Leptospira interrogans serovar Copenhageni, a highly invasive spirochete. Leptospira species colonize a significant proportion of rodent populations worldwide and produce life-threatening infections in mammals. Genomic sequence analysis reveals the presence of a competent transport system with 13 families of genes encoding for major transporters including a three-member component efflux system compatible with the long-term survival of this organism. The leptospiral genome contains a broad array of genes encoding regulatory system, signal transduction and methyl-accepting chemotaxis proteins, reflecting the organism's ability to respond to diverse environmental stimuli. The identification of a complete set of genes encoding the enzymes for the cobalamin biosynthetic pathway and the novel coding genes related to lipopolysaccharide biosynthesis should bring new light to the study of Leptospira physiology. Genes related to toxins, lipoproteins and several surface-exposed proteins may facilitate a better understanding of the Leptospira pathogenesis and may serve as potential candidates for vaccine.

  6. Detection of leptospires in clinically healthy piglets born from sows experimentally infected with Leptospira interrogans serovar Canicola Detecção de leptospiras em leitões clinicamente saudáveis nascidos de matrizes infectadas experimentalmente com Leptospira interrogans sorovar Canicola

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    Francisco Rafael M. Soto

    2006-12-01

    Full Text Available Leptospirosis is an important zoonosis that causes reproductive disorders in swine. The isolation of leptospires from aborted fetuses, stillbirths and weak piglets was obtained in several occasions, however, the bacteria was never isolated from apparently healthy piglets born from apparently healthy infected dams. Six sows of the Landrace breed with a known date of service and pregnancy confirmed by ultrasonography were infected intravenously with 5ml of Leptospira interrogans serovar Canicola inoculum between 76 and 90 days of gestation, and one week after farrowing, at least one piglet per sow was euthanized and samples of liver, kidneys, lungs, heart, spleen and gastric content were taken and examined by PCR. Reproductive disorders or any clinical sign of infection were not observed in the inoculated sows. The piglets born from these animals presented no clinical signs or macroscopic lesions that could be attributed to leptospirosis. All inoculated sows presented anti-leptospires antibodies by microscopic serum-agglutination test (MAT in the postinoculation serum samples and leptospires were not found in the urine as well as were not detected by PCR applied in this material, however, PCR accomplished in kidneys and liver from a euthanized sow presented positive results. Of the total of 12 euthanized piglets, 10 (83.3% presented positive results by PCR in at least one of the kidney, liver, heart, spleen, lung and gastric content samples. The present study reports the vertical transmission of the infection and the detection of leptospires in clinically healthy piglets born from experimentally infected sows, which is important of the epidemiological point of view as the maintenance of clinically healthy infected animals may allow the persistence of the bacteria in the herd, exposing other animals to the risk of infection.A Leptospirose é uma importante zoonose que causa transtornos reprodutivos em suínos. O isolamento de leptospiras de fetos

  7. Pathogenomic inference of virulence-associated genes in Leptospira interrogans.

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    Jason S Lehmann

    Full Text Available Leptospirosis is a globally important, neglected zoonotic infection caused by spirochetes of the genus Leptospira. Since genetic transformation remains technically limited for pathogenic Leptospira, a systems biology pathogenomic approach was used to infer leptospiral virulence genes by whole genome comparison of culture-attenuated Leptospira interrogans serovar Lai with its virulent, isogenic parent. Among the 11 pathogen-specific protein-coding genes in which non-synonymous mutations were found, a putative soluble adenylate cyclase with host cell cAMP-elevating activity, and two members of a previously unstudied ∼15 member paralogous gene family of unknown function were identified. This gene family was also uniquely found in the alpha-proteobacteria Bartonella bacilliformis and Bartonella australis that are geographically restricted to the Andes and Australia, respectively. How the pathogenic Leptospira and these two Bartonella species came to share this expanded gene family remains an evolutionary mystery. In vivo expression analyses demonstrated up-regulation of 10/11 Leptospira genes identified in the attenuation screen, and profound in vivo, tissue-specific up-regulation by members of the paralogous gene family, suggesting a direct role in virulence and host-pathogen interactions. The pathogenomic experimental design here is generalizable as a functional systems biology approach to studying bacterial pathogenesis and virulence and should encourage similar experimental studies of other pathogens.

  8. Generation of mammalian host-adapted Leptospira interrogans by cultivation in peritoneal dialysis membrane chamber implantation in rats

    Science.gov (United States)

    Leptospira interrogans can infect a myriad of mammalian hosts, including humans (Bharti, Nally et al. 2003, Ko, Goarant et al. 2009). Following acquisition by a suitable host, leptospires disseminate via the bloodstream to multiple tissues, including the kidneys, where they adhere to and colonize th...

  9. Whole Genome Analysis of Leptospira licerasiae Provides Insight into Leptospiral Evolution and Pathogenicity

    Science.gov (United States)

    Selengut, Jeremy D.; Harkins, Derek M.; Patra, Kailash P.; Moreno, Angelo; Lehmann, Jason S.; Purushe, Janaki; Sanka, Ravi; Torres, Michael; Webster, Nicholas J.; Vinetz, Joseph M.; Matthias, Michael A.

    2012-01-01

    The whole genome analysis of two strains of the first intermediately pathogenic leptospiral species to be sequenced (Leptospira licerasiae strains VAR010 and MMD0835) provides insight into their pathogenic potential and deepens our understanding of leptospiral evolution. Comparative analysis of eight leptospiral genomes shows the existence of a core leptospiral genome comprising 1547 genes and 452 conserved genes restricted to infectious species (including L. licerasiae) that are likely to be pathogenicity-related. Comparisons of the functional content of the genomes suggests that L. licerasiae retains several proteins related to nitrogen, amino acid and carbohydrate metabolism which might help to explain why these Leptospira grow well in artificial media compared with pathogenic species. L. licerasiae strains VAR010T and MMD0835 possess two prophage elements. While one element is circular and shares homology with LE1 of L. biflexa, the second is cryptic and homologous to a previously identified but unnamed region in L. interrogans serovars Copenhageni and Lai. We also report a unique O-antigen locus in L. licerasiae comprised of a 6-gene cluster that is unexpectedly short compared with L. interrogans in which analogous regions may include >90 such genes. Sequence homology searches suggest that these genes were acquired by lateral gene transfer (LGT). Furthermore, seven putative genomic islands ranging in size from 5 to 36 kb are present also suggestive of antecedent LGT. How Leptospira become naturally competent remains to be determined, but considering the phylogenetic origins of the genes comprising the O-antigen cluster and other putative laterally transferred genes, L. licerasiae must be able to exchange genetic material with non-invasive environmental bacteria. The data presented here demonstrate that L. licerasiae is genetically more closely related to pathogenic than to saprophytic Leptospira and provide insight into the genomic bases for its infectiousness

  10. A LigA three-domain region protects hamsters from lethal infection by Leptospira interrogans.

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    Mariana L Coutinho

    2011-12-01

    Full Text Available The leptospiral LigA protein consists of 13 bacterial immunoglobulin-like (Big domains and is the only purified recombinant subunit vaccine that has been demonstrated to protect against lethal challenge by a clinical isolate of Leptospira interrogans in the hamster model of leptospirosis. We determined the minimum number and location of LigA domains required for immunoprotection. Immunization with domains 11 and 12 was found to be required but insufficient for protection. Inclusion of a third domain, either 10 or 13, was required for 100% survival after intraperitoneal challenge with Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130. As in previous studies, survivors had renal colonization; here, we quantitated the leptospiral burden by qPCR to be 1.2×10(3 to 8×10(5 copies of leptospiral DNA per microgram of kidney DNA. Although renal histopathology in survivors revealed tubulointerstitial changes indicating an inflammatory response to the infection, blood chemistry analysis indicated that renal function was normal. These studies define the Big domains of LigA that account for its vaccine efficacy and highlight the need for additional strategies to achieve sterilizing immunity to protect the mammalian host from leptospiral infection and its consequences.

  11. Characterization of acetyl-CoA and propionyl-CoA carboxylases encoded by Leptospira interrogans serovar Lai: an initial biochemical study for leptospiral gluconeogenesis via anaplerotic CO2 assimilation

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    Nanqiu Peng; Yi Zhong; Qing Zhang; Mingyue Zheng; Wei Zhao; Hualiang Jiang; Chen Yang; Xiaokui Guo; Guoping Zhao

    2012-01-01

    Leptospira interrogans is the causative agent of leptospirosis.The in vitro growth of L.interrogans requires CO2 and a partial 3-hydroxypropionate pathway involving two acyl-CoA carboxylases was suggested by genomic analysis to assimilate CO2.Either set of the candidate genes heterologously co-expressed in Escherichia coli was able to demonstrate both acetyl-CoA carboxylase (ACC)and propionyl-CoA carboxylase (PCC) activities.The trisubunit holoenzyme (LA_2736-LA_2735 and LA_3803),although failed to be purified,was designated ACC based on its substrate preference toward acetyl-CoA.The partially purified bi-subunit holoenzyme (LA_2432-LA_2433) has a considerably higher activity against propionyi-CoA as the substrate than that of acetyl-CoA,and thus,designated PCC.Native polyacrylamide gel electrophoresis indicated that this PCC has a molecular mass of around 669 kDa,suggesting an α4β4 quaternary structure and both structural homology modeling and site-directed mutagenesis analysis of its carboxyltransferase subunit (LA_2433) indicated that the A431 residue located at the bottom of the putative substrate binding pocket may play an important role in substrate specificity determination.Both transcriptomic and proteomic data indicated that enzymes involved in the suggested partial 3-hydroxypropionate pathway were expressed in vivo in addition to ACC/PCC and the homologous genes in genomes of other Leptospira species were re-annotated accordingly.However,as the in vitro detected specific activity of ACC in the crude cell extract was too low to account for the growth of the bacterium in Ellinghausen-McCulloughJohnson-Harris minimal medium,further systematic analysis is required to unveil the mechanism of gluconeogenesis via anaplerotic CO2 assimilation in Leptospira species.

  12. Multilocus Sequence Analysis for Typing Leptospira interrogans and Leptospira kirschneri▿ †

    OpenAIRE

    2009-01-01

    Fifty-three strains belonging to the pathogenic species Leptospira interrogans and Leptospira kirschneri were analyzed by multilocus sequence analysis. The species formed two distinct branches. In the L. interrogans branch, the phylogenetic tree clustered the strains into three subgroups. Genogroups and serogroups were superimposed but not strictly.

  13. Heterogenic colonization patterns by Leptospira interrogans in Rattus norvegicus from urban slums

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    Santos, Ana Amélia Nunes; Figueira, Cláudio Pereira; dos Reis, Mitermayer Galvão; Costa, Federico; Ristow, Paula

    2015-01-01

    Abstract We evaluated the renal colonization by Leptospira interrogans in Rattus norvegicus (rats), as it is the major natural reservoir of urban leptospirosis. We caught 72 R. norvegicus, out of which 32 were found to be positive for L. interrogans by immunofluorescence assay. From these rats, we selected 17 and divided them into six groups based on the mass-age/sex. We performed the immunohistochemistry test against L. interrogans in the kidney sections of the rats and systematically counted the colonized tubules (CTs) in 20 fields. The proportion of positive fields varied from 5% to 95%. The number of CTs in 20 fields varied from 0.5 to 85.5. These differences were not related to age or sex of the animals. The characterization of leptospiral colonization patterns in the natural reservoirs is important to better understand the host-pathogen interactions in leptospirosis. PMID:26691476

  14. NEW WILDLIFE HOSTS OF Leptospira interrogans IN CAMPECHE, MEXICO

    OpenAIRE

    ESPINOSA-MARTÍNEZ,Deborah V.; SÁNCHEZ-MONTES,Daniel Sokani; León-Paniagua,Livia; Ríos-Muñoz, César A.; BERZUNZA-CRUZ,Miriam; BECKER,Ingeborg

    2015-01-01

    Leptospira interrogans has been identified to cause leptospirosis, a widespread zoonotic disease that has been identified in domestic and wild animals. This work analyzed kidneys from two species of wild rodents from the state of Campeche, Mexico. Analyses were made by PCR using specific primers for detection of Leptospira interrogans DNA. The rodent species that tested positive were Heteromys gaumeri and Ototylomys phyllotis, both of which are new hosts for the bacteria in Southeastern Mexic...

  15. Adhesins of Leptospira interrogans Mediate the Interaction to Fibrinogen and Inhibit Fibrin Clot Formation In Vitro

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    Oliveira, Rosane; Domingos, Renan F.; Siqueira, Gabriela H.; Fernandes, Luis G.; Souza, Natalie M.; Vieira, Monica L.; de Morais, Zenaide M.; Vasconcellos, Silvio A.; Nascimento, Ana L. T. O.

    2013-01-01

    We report in this work that Leptospira strains, virulent L. interrogans serovar Copenhageni, attenuated L. interrogans serovar Copenhageni and saprophytic L. biflexa serovar Patoc are capable of binding fibrinogen (Fg). The interaction of leptospires with Fg inhibits thrombin- induced fibrin clot formation that may affect the haemostatic equilibrium. Additionally, we show that plasminogen (PLG)/plasmin (PLA) generation on the surface of Leptospira causes degradation of human Fg. The data suggest that PLA-coated leptospires were capable to employ their proteolytic activity to decrease one substrate of the coagulation cascade. We also present six leptospiral adhesins and PLG- interacting proteins, rLIC12238, Lsa33, Lsa30, OmpL1, rLIC11360 and rLIC11975, as novel Fg-binding proteins. The recombinant proteins interact with Fg in a dose-dependent and saturable fashion when increasing protein concentration was set to react to a fix human Fg concentration. The calculated dissociation equilibrium constants (KD) of these reactions ranged from 733.3±276.8 to 128±89.9 nM for rLIC12238 and Lsa33, respectively. The interaction of recombinant proteins with human Fg resulted in inhibition of fibrin clot by thrombin-catalyzed reaction, suggesting that these versatile proteins could mediate Fg interaction in Leptospira. Our data reveal for the first time the inhibition of fibrin clot by Leptospira spp. and presents adhesins that could mediate these interactions. Decreasing fibrin clot would cause an imbalance of the coagulation cascade that may facilitate bleeding and help bacteria dissemination PMID:24009788

  16. Determination of the genus-specific antigens in outer membrane proteins from the strains of Leptospira interrogans and Leptospira biflexa with different virulence

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    罗依惠; 严杰; 毛亚飞; 李淑萍

    2004-01-01

    Objective:To determine the existence of genus-specific antigens in outer membrane proteins (OMPs) of leptospira with different virulence. Methods: Microscope agglutination test (MAT) was applied to detect the agglutination between commercial rabbit antiserum against leptospiral genus-specific TR/Patoc I antigen and 17 strains of Leptospira interrongans belonging to 15 serogroups and 2 strains of Leptospira biflexa belonging to 2 serogroups.The outer envelopes (OEs) of L.interrogans serogroup Icterohaemorrhagiae serovar lai strain lai (56601) with strong virulence and serogroup Pomona serovar pomona strain Luo (56608) with low virulence,and L.biflexa serogroup Semaranga serovar patoc strain Patoc I without virulence were prepared by using the method reported in Auran et al.(1972).OMPs in the OEs were obtained by treatment with sodium deoxycholate. SDS-PAGE and western blot were used for analyzing the features of the OMPs on electrophoretic pattern and the immunoreactivity to the antiserum against TR/Patoc I antigen, respectively. Results:All the tested strains belonging to different leptospiral serogroups agglutinated to the antiserum against leptospiral genus-specific TR/Patoc I antigen with agglutination titers ranging from 1:256-1:512. A similar SDS-PAGE pattern of the OMPs from the three strains of leptospira with different virulence was shown and the molecular weight of a major protein fragment in the OMPs was found to be approximately 60 KDa.A positive protein fragment with approximately 32 KDa confirmed by Western blot,was able to react with the antiserum against leptospiral genus-specific TR/Patoc I antigen, and was found in each the OMPs of the three stains of leptospira.Conclusion: There are genus-specific antigens on the surface of L.interrogans and L.biflexa. The OMP with molecular weight of 32 KDa may be one of the genus-specific protein antigens of leptospira.

  17. Determination of the genus-specific antigens in outer membrane proteins from the strains of Leptospira interrogans and Leptospira biflexa with different virulence

    Institute of Scientific and Technical Information of China (English)

    罗依惠; 严杰; 毛亚飞; 李淑萍

    2004-01-01

    Objective: To determine the existence of genus-specific antigens in outer membrane proteins (OMPs) of leptospira with different virulence. Methods: Microscope agglutination test (MAT) was applied to detect the agglutination between commercial rabbit antiserum against leptospiral genus-specific TR/Patoc I antigen and 17 strains of Leptospira interrongans belonging to 15 serogroups and 2 strains of Leptospira biflexa belonging to 2 serogroups. The outer envelopes (OEs) of L.interrogans serogroup Icterohaemorrhagiae serovar lai strain lai (56601) with strong virulence and serogroup Pomona serovar pomona strain Luo (56608) with low virulence, and L.biflexa serogroup Semaranga serovar patoc strain Patoc I without virulence were prepared by using the method reported in Auran et al.(1972). OMPs in the OEs were obtained by treatment with sodium deoxycholate. SDS-PAGE and western blot were used for analyzing the features of the OMPs on electrophoretic pattern and the immunoreactivity to the antiserum against TR/Patoc I antigen, respectively. Results: All the tested strains belonging to different leptospiral serogroups agglutinated to the antiserum against leptospiral genus-specific TR/Patoc I antigen with agglutination titers ranging from 1:256-1:512. A similar SDS-PAGE pattern of the OMPs from the three strains of leptospira with different virulence was shown and the molecular weight of a major protein fragment in the OMPs was found to be approximately 60 KDa. A positive protein fragment with approximately 32 KDa confirmed by Western blot, was able to react with the antiserum against leptospiral genus-specific TR/Patoc I antigen, and was found in each the OMPs of the three stains of leptospira. Conclusion: There are genus-specific antigens on the surface of L.interrogans and L.biflexa. The OMP with molecular weight of 32 KDa may be one of the genus-specific protein antigens of leptospira.

  18. Isolation of Leptospira interrogans Hardjoprajitno from vaginal fluid of a clinically healthy ewe suggests potential for venereal transmission.

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    Director, A; Penna, B; Hamond, C; Loureiro, A P; Martins, G; Medeiros, M A; Lilenbaum, W

    2014-09-01

    A total of 15 adult ewes from one flock known to be seroreactive for leptospirosis was studied. Urine and vaginal fluid were collected from each animal to test for the presence of leptospires using bacterial culture and conventional PCR methods. One pure culture of Leptospira sp. was obtained from the vaginal fluid sample of a non-pregnant ewe. The isolate was characterized by DNA sequencing of the rrs and secY genes, variable-number of tandem-repeats (VNTR) analysis and serogrouping, and the isolate was typed as Leptospira interrogans serogroup Sejroe serovar Hardjo type Hardjoprajitno. This report indicates the presence of viable Leptospira in the vaginal fluid of a ewe, suggesting the potential for venereal transmission of leptospires in sheep.

  19. Adipose tissue is the first colonization site of Leptospira interrogans in subcutaneously infected hamsters

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    Ozuru, Ryo; Saito, Mitsumasa; Kanemaru, Takaaki; Miyahara, Satoshi; Villanueva, Sharon Y. A. M.; Murray, Gerald L.; Adler, Ben; Fujii, Jun; Yoshida, Shin-ichi

    2017-01-01

    Leptospirosis is one of the most widespread zoonoses in the world, and its most severe form in humans, “Weil’s disease,” may lead to jaundice, hemorrhage, renal failure, pulmonary hemorrhage syndrome, and sometimes,fatal multiple organ failure. Although the mechanisms underlying jaundice in leptospirosis have been gradually unraveled, the pathophysiology and distribution of leptospires during the early stage of infection are not well understood. Therefore, we investigated the hamster leptospirosis model, which is the accepted animal model of human Weil’s disease, by using an in vivo imaging system to observe the whole bodies of animals infected with Leptospira interrogans and to identify the colonization and growth sites of the leptospires during the early phase of infection. Hamsters, infected subcutaneously with 104 bioluminescent leptospires, were analyzed by in vivo imaging, organ culture, and microscopy. The results showed that the luminescence from the leptospires spread through each hamster’s body sequentially. The luminescence was first detected at the injection site only, and finally spread to the central abdomen, in the liver area. Additionally, the luminescence observed in the adipose tissue was the earliest detectable compared with the other organs, indicating that the leptospires colonized the adipose tissue at the early stage of leptospirosis. Adipose tissue cultures of the leptospires became positive earlier than the blood cultures. Microscopic analysis revealed that the leptospires colonized the inner walls of the blood vessels in the adipose tissue. In conclusion, this is the first study to report that adipose tissue is an important colonization site for leptospires, as demonstrated by microscopy and culture analyses of adipose tissue in the hamster model of Weil’s disease. PMID:28245231

  20. Live imaging of bioluminescent leptospira interrogans in mice reveals renal colonization as a stealth escape from the blood defenses and antibiotics.

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    Gwenn Ratet

    2014-12-01

    Full Text Available Leptospira (L. interrogans are bacteria responsible for a worldwide reemerging zoonosis. Some animals asymptomatically carry L. interrogans in their kidneys and excrete bacteria in their urine, which contaminates the environment. Humans are infected through skin contact with leptospires and develop mild to severe leptospirosis. Previous attempts to construct fluorescent or bioluminescent leptospires, which would permit in vivo visualization and investigation of host defense mechanisms during infection, have been unsuccessful. Using a firefly luciferase cassette and random transposition tools, we constructed bioluminescent chromosomal transformants in saprophytic and pathogenic leptospires. The kinetics of leptospiral dissemination in mice, after intraperitoneal inoculation with a pathogenic transformant, was tracked by bioluminescence using live imaging. For infective doses of 106 to 107 bacteria, we observed dissemination and exponential growth of leptospires in the blood, followed by apparent clearance of bacteria. However, with 2×108 bacteria, the septicemia led to the death of mice within 3 days post-infection. In surviving mice, one week after infection, pathogenic leptospires reemerged only in the kidneys, where they multiplied and reached a steady state, leading to a sustained chronic renal infection. These experiments reveal that a fraction of the leptospiral population escapes the potent blood defense, and colonizes a defined number of niches in the kidneys, proportional to the infective dose. Antibiotic treatments failed to eradicate leptospires that colonized the kidneys, although they were effective against L. interrogans if administered before or early after infection. To conclude, mice infected with bioluminescent L. interrogans proved to be a novel model to study both acute and chronic leptospirosis, and revealed that, in the kidneys, leptospires are protected from antibiotics. These bioluminescent leptospires represent a

  1. Leptospira interrogans stably infects zebrafish embryos, altering phagocyte behavior and homing to specific tissues.

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    J Muse Davis

    Full Text Available Leptospirosis is an extremely widespread zoonotic infection with outcomes ranging from subclinical infection to fatal Weil's syndrome. Despite the global impact of the disease, key aspects of its pathogenesis remain unclear. To examine in detail the earliest steps in the host response to leptospires, we used fluorescently labelled Leptospira interrogans serovar Copenhageni to infect 30 hour post fertilization zebrafish embryos by either the caudal vein or hindbrain ventricle. These embryos have functional innate immunity but have not yet developed an adaptive immune system. Furthermore, they are optically transparent, allowing direct visualization of host-pathogen interactions from the moment of infection. We observed rapid uptake of leptospires by phagocytes, followed by persistent, intracellular infection over the first 48 hours. Phagocytosis of leptospires occasionally resulted in formation of large cellular vesicles consistent with apoptotic bodies. By 24 hours, clusters of infected phagocytes were accumulating lateral to the dorsal artery, presumably in early hematopoietic tissue. Our observations suggest that phagocytosis may be a key defense mechanism in the early stages of leptospirosis, and that phagocytic cells play roles in immunopathogenesis and likely in the dissemination of leptospires to specific target tissues.

  2. Post-translational modification of LipL32 during Leptospira interrogans infection.

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    Timothy D Witchell

    2014-10-01

    Full Text Available BACKGROUND: Leptospirosis, a re-emerging disease of global importance caused by pathogenic Leptospira spp., is considered the world's most widespread zoonotic disease. Rats serve as asymptomatic carriers of pathogenic Leptospira and are critical for disease spread. In such reservoir hosts, leptospires colonize the kidney, are shed in the urine, persist in fresh water and gain access to a new mammalian host through breaches in the skin. METHODOLOGY/PRINCIPAL FINDINGS: Previous studies have provided evidence for post-translational modification (PTM of leptospiral proteins. In the current study, we used proteomic analyses to determine the presence of PTMs on the highly abundant leptospiral protein, LipL32, from rat urine-isolated L. interrogans serovar Copenhageni compared to in vitro-grown organisms. We observed either acetylation or tri-methylation of lysine residues within multiple LipL32 peptides, including peptides corresponding to regions of LipL32 previously identified as epitopes. Intriguingly, the PTMs were unique to the LipL32 peptides originating from in vivo relative to in vitro grown leptospires. The identity of each modified lysine residue was confirmed by fragmentation pattern analysis of the peptide mass spectra. A synthetic peptide containing an identified tri-methylated lysine, which corresponds to a previously identified LipL32 epitope, demonstrated significantly reduced immunoreactivity with serum collected from leptospirosis patients compared to the peptide version lacking the tri-methylation. Further, a subset of the identified PTMs are in close proximity to the established calcium-binding and putative collagen-binding sites that have been identified within LipL32. CONCLUSIONS/SIGNIFICANCE: The exclusive detection of PTMs on lysine residues within LipL32 from in vivo-isolated L. interrogans implies that infection-generated modification of leptospiral proteins may have a biologically relevant function during the course of

  3. Genetic diversity among major endemic strains of Leptospira interrogans in China

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    Zhang Zhi-Ming

    2007-07-01

    Full Text Available Abstract Background Leptospirosis is a world-widely distributed zoonosis. Humans become infected via exposure to pathogenic Leptospira spp. from contaminated water or soil. The availability of genomic sequences of Leptospira interrogans serovar Lai and serovar Copenhageni opened up opportunities to identify genetic diversity among different pathogenic strains of L. interrogans representing various kinds of serotypes (serogroups and serovars. Results Comparative genomic hybridization (CGH analysis was used to compare the gene content of L. interrogans serovar Lai strain Lai with that of other 10 L. interrogans strains prevailed in China and one identified from Brazil using a microarray spotted with 3,528 protein coding sequences (CDSs of strain Lai. The cutoff ratio of sample/reference (S/R hybridization for detecting the absence of genes from one tested strain was set by comparing the ratio of S/R hybridization and the in silico sequence similarities of strain Lai and serovar Copenhageni strain Fiocruz L1-130. Among the 11 strains tested, 275 CDSs were found absent from at least one strain. The common backbone of the L. interrogans genome was estimated to contain about 2,917 CDSs. The genes encoding fundamental cellular functions such as translation, energy production and conversion were conserved. While strain-specific genes include those that encode proteins related to either cell surface structures or carbohydrate transport and metabolism. We also found two genomic islands (GIs in strain Lai containing genes divergently absent in other strains. Because genes encoding proteins with potential pathogenic functions are located within GIs, these elements might contribute to the variations in disease manifestation. Differences in genes involved in O-antigen biosynthesis were also identified for strains belonging to different serogroups, which offers an opportunity for future development of genomic typing tools for serological classification

  4. Generation of Mammalian Host-adapted Leptospira interrogans by Cultivation in Peritoneal Dialysis Membrane Chamber Implantation in Rats.

    Science.gov (United States)

    Grassmann, André Alex; McBride, Alan John Alexander; Nally, Jarlath E; Caimano, Melissa J

    2015-07-20

    Leptospira interrogans can infect a myriad of mammalian hosts, including humans (Bharti et al., 2003; Ko et al., 2009). Following acquisition by a suitable host, leptospires disseminate via the bloodstream to multiple tissues, including the kidneys, where they adhere to and colonize the proximal convoluted renal tubules (Athanazio et al., 2008). Infected hosts shed large number of spirochetes in their urine and the leptospires can survive in different environmental conditions before transmission to another host. Differential gene expression by Leptospira spp. permits adaption to these new conditions. Here we describe a protocol for the cultivation of Leptospira interrogans within Dialysis Membrane Chambers (DMCs) implanted into the peritoneal cavities of Sprague-Dawley rats (Caimano et al., 2014). This technique was originally developed to study mammalian adaption by the Lyme disease spirochete, Borrelia burgdorferi (Akins et al., 1998; Caimano, 2005). The small pore size (8,000 MWCO) of the dialysis membrane tubing used for this procedure permits access to host nutrients but excludes host antibodies and immune effector cells. Given the physiological and environmental similarities between DMCs and the proximal convoluted renal tubule, we reasoned that the DMC model would be suitable for studying in vivo gene expression by L. interrogans. In a 20 to 30 min procedure, DMCs containing virulent leptospires are surgically-implanted into the rat peritoneal cavity. Nine to 11 days post-implantation, DMCs are explanted and organisms recovered. Typically, a single DMC yields ~10(9) mammalian host-adapted leptospires (Caimano et al., 2014). In addition to providing a facile system for studying the transcriptional and physiologic changes pathogenic L. interrogans undergo within the mammal, the DMC model also provides a rationale basis for selecting new targets for mutagenesis and the identification of novel virulence determinants. Caution: Leptospira interrogans is a BSL-2

  5. Identificación de antígenos inmunorreactivos de Leptospira interrogans Identification of immunoreactive antigens of Leptospira interrogans

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    A. Carrizo

    2009-09-01

    Full Text Available Se estudió un lote de 28 sueros de llama (Lama gama de la provincia de Jujuy, Argentina, a fin de identificar antígenos inmunorreactivos contra Leptospira interrogans. Se utilizaron distintas preparaciones antigénicas de la bacteria para estudiar la inmunorreactividad mediante microaglutinación (MAT, ELISA y Western inmunoblot. Un pool de sueros bovinos positivos a la MAT fue empleado como control. Todos los sueros de llama fueron negativos mediante MAT e igual resultado se observó mediante ELISA. Dos de los 28 sueros de llama y el pool de sueros bovinos positivos, al ser evaluados por Western inmunoblot, arrojaron resultados positivos y permitieron identificar proteínas inmunorreactivas. Por MALDI-TOF se logró establecer que la proteína asociada a los dos sueros de llama inmunorreactivos era una flagelina periplásmica de Leptospira interrogans serovar Lai STR, mientras que la asociada al pool de sueros bovinos positivos a Leptospira sp. se trataba de una lipoproteína de la membrana externa de Leptospira interrogans serovar Ballum, LipL21. Estas proteínas podrían ser utilizadas en el diseño de un nuevo ELISA aplicado al diagnóstico temprano de leptospirosis, ya sea en distintos tipos de ganado como así también en reservorios silvestres.A batch of 28 llama (Lama gama sera from Jujuy province in Argentina was studied in order to identify immune reactive antigens to Leptospira interrogans. Different antigenic preparations from the bacterium were used to study the immune reactivity by the microagglutinattion (MAT, ELISA and Western immunoblot tests. A control pool of positive bovine sera was used. All the llama sera were negative to MAT as well as to ELISA. Two of the llama sera and the positive bovine sera pool rendered positive results when evaluated by Western immunoblot, allowing the identification of immune reactive proteins. These proteins were identified by MALDI-TOF. A periplasmic flagellin of Leptospira interrogans serovar

  6. New wildlife hosts of Leptospira interrogans in Campeche, Mexico.

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    Espinosa-Martínez, Deborah V; Sánchez-Montes, Daniel Sokani; León-Paniagua, Livia; Ríos-Muñoz, César A; Berzunza-Cruz, Miriam; Becker, Ingeborg

    2015-01-01

    Leptospira interrogans has been identified to cause leptospirosis, a widespread zoonotic disease that has been identified in domestic and wild animals. This work analyzed kidneys from two species of wild rodents from the state of Campeche, Mexico. Analyses were made by PCR using specific primers for detection of Leptospira interrogans DNA. The rodent species that tested positive were Heteromys gaumeri and Ototylomys phyllotis, both of which are new hosts for the bacteria in Southeastern Mexico. These records provide new insights into the disease's transmission that should be studied carefully in order to identify other potential host species, including humans, which are at risk of becoming infected if they are in contact with infected wildlife.

  7. NEW WILDLIFE HOSTS OF Leptospira interrogans IN CAMPECHE, MEXICO

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    Deborah V. ESPINOSA-MARTÍNEZ

    2015-04-01

    Full Text Available Leptospira interrogans has been identified to cause leptospirosis, a widespread zoonotic disease that has been identified in domestic and wild animals. This work analyzed kidneys from two species of wild rodents from the state of Campeche, Mexico. Analyses were made by PCR using specific primers for detection of Leptospira interrogans DNA. The rodent species that tested positive were Heteromys gaumeri and Ototylomys phyllotis, both of which are new hosts for the bacteria in Southeastern Mexico. These records provide new insights into the disease’s transmission that should be studied carefully in order to identify other potential host species, including humans, which are at risk of becoming infected if they are in contact with infected wildlife.

  8. Leptospira interrogans endostatin-like outer membrane proteins bind host fibronectin, laminin and regulators of complement.

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    Brian Stevenson

    Full Text Available The pathogenic spirochete Leptospira interrogans disseminates throughout its hosts via the bloodstream, then invades and colonizes a variety of host tissues. Infectious leptospires are resistant to killing by their hosts' alternative pathway of complement-mediated killing, and interact with various host extracellular matrix (ECM components. The LenA outer surface protein (formerly called LfhA and Lsa24 was previously shown to bind the host ECM component laminin and the complement regulators factor H and factor H-related protein-1. We now demonstrate that infectious L. interrogans contain five additional paralogs of lenA, which we designated lenB, lenC, lenD, lenE and lenF. All six genes encode domains predicted to bear structural and functional similarities with mammalian endostatins. Sequence analyses of genes from seven infectious L. interrogans serovars indicated development of sequence diversity through recombination and intragenic duplication. LenB was found to bind human factor H, and all of the newly-described Len proteins bound laminin. In addition, LenB, LenC, LenD, LenE and LenF all exhibited affinities for fibronectin, a distinct host extracellular matrix protein. These characteristics suggest that Len proteins together facilitate invasion and colonization of host tissues, and protect against host immune responses during mammalian infection.

  9. Caracterization of the SOS response in Leptospira interrogans sorovar Copenhageni

    OpenAIRE

    Luciane Schons da Fonseca

    2015-01-01

    Leptospira is a basal genus in an ancient group of bacteria, the spirochetes. The pathogenic species are responsible for leptospirosis, a disease with worldwide distribution and of public health importance in developed tropical countries. L. interrogans serovar Copenhageni is the agent for the majority of human leptospirosis in Brazil. In this work, we used a great variety of experimental approaches to characterize the SOS system in this serovar, to identify its impact in general DNA damage r...

  10. Production and characterization of monoclonal antibodies to the edta extract of Leptospira interrogans, serovar icterohaemorrhagiae

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    Lilian Terezinha de Queiroz Leite

    1996-10-01

    Full Text Available Monoclonal antibodies (MABs ivere produced against an etbylenediaminetetraacetate (EDTA extract of Leptospira interrogans serovar icterohaemorrhagiae being characterized by gel precipitation as IgM and IgG (IgGl and IgG2b. The EDTA extract was detected as several bands by silver staining in SDS-PAGE. In the Western blot the bands around 20 KDa reacted with a monoclonal antibody, 47B4D6, and was oxidized by periodate and was not digested by pronase, suggesting that the determinant is of carbohydrate nature, lmmunocytochemistry, using colloidal gold labeling, showed that an EDTA extract determinant recognized by monoclonal antibody 47B4D6, is localized under the outer envelope of serovar icterohaemorrhagiae. Hoe AIAB raised against the EDTA extract was not able to protect hamsters from lethal challenge with virulent homologous leptospires.

  11. Features of Two New Proteins with OmpA-Like Domains Identified in the Genome Sequences of Leptospira interrogans

    Science.gov (United States)

    Teixeira, Aline F.; de Morais, Zenaide M.; Kirchgatter, Karin; Romero, Eliete C.; Vasconcellos, Silvio A.; Nascimento, Ana Lucia T. O.

    2015-01-01

    Leptospirosis is an acute febrile disease caused by pathogenic spirochetes of the genus Leptospira. It is considered an important re-emerging infectious disease that affects humans worldwide. The knowledge about the mechanisms by which pathogenic leptospires invade and colonize the host remains limited since very few virulence factors contributing to the pathogenesis of the disease have been identified. Here, we report the identification and characterization of two new leptospiral proteins with OmpA-like domains. The recombinant proteins, which exhibit extracellular matrix-binding properties, are called Lsa46 - LIC13479 and Lsa77 - LIC10050 (Leptospiral surface adhesins of 46 and 77 kDa, respectively). Attachment of Lsa46 and Lsa77 to laminin was specific, dose dependent and saturable, with KD values of 24.3 ± 17.0 and 53.0 ± 17.5 nM, respectively. Lsa46 and Lsa77 also bind plasma fibronectin, and both adhesins are plasminogen (PLG)-interacting proteins, capable of generating plasmin (PLA) and as such, increase the proteolytic ability of leptospires. The proteins corresponding to Lsa46 and Lsa77 are present in virulent L. interrogans L1-130 and in saprophyte L. biflexa Patoc 1 strains, as detected by immunofluorescence. The adhesins are recognized by human leptospirosis serum samples at the onset and convalescent phases of the disease, suggesting that they are expressed during infection. Taken together, our data could offer valuable information to the understanding of leptospiral pathogenesis. PMID:25849456

  12. Features of two new proteins with OmpA-like domains identified in the genome sequences of Leptospira interrogans.

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    Aline F Teixeira

    Full Text Available Leptospirosis is an acute febrile disease caused by pathogenic spirochetes of the genus Leptospira. It is considered an important re-emerging infectious disease that affects humans worldwide. The knowledge about the mechanisms by which pathogenic leptospires invade and colonize the host remains limited since very few virulence factors contributing to the pathogenesis of the disease have been identified. Here, we report the identification and characterization of two new leptospiral proteins with OmpA-like domains. The recombinant proteins, which exhibit extracellular matrix-binding properties, are called Lsa46 - LIC13479 and Lsa77 - LIC10050 (Leptospiral surface adhesins of 46 and 77 kDa, respectively. Attachment of Lsa46 and Lsa77 to laminin was specific, dose dependent and saturable, with KD values of 24.3 ± 17.0 and 53.0 ± 17.5 nM, respectively. Lsa46 and Lsa77 also bind plasma fibronectin, and both adhesins are plasminogen (PLG-interacting proteins, capable of generating plasmin (PLA and as such, increase the proteolytic ability of leptospires. The proteins corresponding to Lsa46 and Lsa77 are present in virulent L. interrogans L1-130 and in saprophyte L. biflexa Patoc 1 strains, as detected by immunofluorescence. The adhesins are recognized by human leptospirosis serum samples at the onset and convalescent phases of the disease, suggesting that they are expressed during infection. Taken together, our data could offer valuable information to the understanding of leptospiral pathogenesis.

  13. Genome-Wide Transcriptional Start Site Mapping and sRNA Identification in the Pathogen Leptospira interrogans

    Science.gov (United States)

    Zhukova, Anna; Fernandes, Luis Guilherme; Hugon, Perrine; Pappas, Christopher J.; Sismeiro, Odile; Coppée, Jean-Yves; Becavin, Christophe; Malabat, Christophe; Eshghi, Azad; Zhang, Jun-Jie; Yang, Frank X.; Picardeau, Mathieu

    2017-01-01

    Leptospira are emerging zoonotic pathogens transmitted from animals to humans typically through contaminated environmental sources of water and soil. Regulatory pathways of pathogenic Leptospira spp. underlying the adaptive response to different hosts and environmental conditions remains elusive. In this study, we provide the first global Transcriptional Start Site (TSS) map of a Leptospira species. RNA was obtained from the pathogen Leptospira interrogans grown at 30°C (optimal in vitro temperature) and 37°C (host temperature) and selectively enriched for 5′ ends of native transcripts. A total of 2865 and 2866 primary TSS (pTSS) were predicted in the genome of L. interrogans at 30 and 37°C, respectively. The majority of the pTSSs were located between 0 and 10 nucleotides from the translational start site, suggesting that leaderless transcripts are a common feature of the leptospiral translational landscape. Comparative differential RNA-sequencing (dRNA-seq) analysis revealed conservation of most pTSS at 30 and 37°C. Promoter prediction algorithms allow the identification of the binding sites of the alternative sigma factor sigma 54. However, other motifs were not identified indicating that Leptospira consensus promoter sequences are inherently different from the Escherichia coli model. RNA sequencing also identified 277 and 226 putative small regulatory RNAs (sRNAs) at 30 and 37°C, respectively, including eight validated sRNAs by Northern blots. These results provide the first global view of TSS and the repertoire of sRNAs in L. interrogans. These data will establish a foundation for future experimental work on gene regulation under various environmental conditions including those in the host. PMID:28154810

  14. Sheep as maintenance host for Leptospira interrogans serovar hardjo subtype hardjobovis.

    Science.gov (United States)

    Gerritsen, M J; Koopmans, M J; Peterse, D; Olyhoek, T

    1994-09-01

    Transmission of Leptospira interrogans serovar hardjo subtype hardjobovis from naturally infected sheep to uninfected sheep and calves was studied. A microscopic agglutination test and ELISA were used to determine specific antibody responses in serum. Polymerase chain reaction was used to detect bacterial shedding in urine. Six sheep were derived from a dairy farm where cows were infected with L hardjobovis. Three of these sheep were seropositive for L hardjobovis, and 1 also shed leptospires in the urine. The other 2 sheep shed leptospires in the urine 7 days after the first observation date. The 6 sheep were placed on an isolated pasture together with a second group of 6 noninfected sheep. During the observation period of 140 days, 1 sheep of the second group became infected with L hardjobovis. On 5 consecutive days, a urine mixture from the 4 infected sheep was sprayed on the heads of 4 noninfected calves. Within 56 days, all calves that had been sprayed with urine shed L hardjobovis in the urine and became seropositive for L hardjobovis.

  15. A comprehensive approach to identification of surface-exposed, outer membrane-spanning proteins of Leptospira interrogans.

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    Marija Pinne

    Full Text Available Leptospirosis is a zoonosis with worldwide distribution caused by pathogenic spirochetes belonging to the genus Leptospira. The leptospiral life cycle involves transmission via fresh water and colonization of the renal tubules of their reservoir hosts or infection of accidental hosts, including humans. Bacterial outer membrane proteins (OMPs, particularly those with surface-exposed regions, play crucial roles in virulence mechanisms of pathogens and the adaptation to various environmental conditions, including those of the mammalian host. Little is known about the surface-exposed OMPs in Leptospira, particularly those with outer membrane-spanning domains. Herein, we describe a comprehensive strategy for identification and characterization of leptospiral transmembrane OMPs. The genomic sequence of L. interrogans serovar Copenhageni strain Fiocruz L1-130 allowed us to employ the beta-barrel prediction programs, PRED-TMBB and TMBETA-NET, to identify potential transmembrane OMPs. Several complementary methods were used to characterize four novel OMPs, designated OmpL36, OmpL37, OmpL47 and OmpL54. In addition to surface immunofluorescence and surface biotinylation, we describe surface proteolysis of intact leptospires as an improved method for determining the surface exposure of leptospiral proteins. Membrane integration was confirmed using techniques for removal of peripheral membrane proteins. We also demonstrate deficiencies in the Triton X-114 fractionation method for assessing the outer membrane localization of transmembrane OMPs. Our results establish a broadly applicable strategy for the elucidation of novel surface-exposed outer membrane-spanning proteins of Leptospira, an essential step in the discovery of potential virulence factors, diagnostic antigens and vaccine candidates.

  16. The multifunctional LigB adhesin binds homeostatic proteins with potential roles in cutaneous infection by pathogenic Leptospira interrogans.

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    Henry A Choy

    Full Text Available Leptospirosis is a potentially fatal zoonotic disease in humans and animals caused by pathogenic spirochetes, such as Leptospira interrogans. The mode of transmission is commonly limited to the exposure of mucous membrane or damaged skin to water contaminated by leptospires shed in the urine of carriers, such as rats. Infection occurs during seasonal flooding of impoverished tropical urban habitats with large rat populations, but also during recreational activity in open water, suggesting it is very efficient. LigA and LigB are surface localized proteins in pathogenic Leptospira strains with properties that could facilitate the infection of damaged skin. Their expression is rapidly induced by the increase in osmolarity encountered by leptospires upon transition from water to host. In addition, the immunoglobulin-like repeats of the Lig proteins bind proteins that mediate attachment to host tissue, such as fibronectin, fibrinogen, collagens, laminin, and elastin, some of which are important in cutaneous wound healing and repair. Hemostasis is critical in a fresh injury, where fibrinogen from damaged vasculature mediates coagulation. We show that fibrinogen binding by recombinant LigB inhibits fibrin formation, which could aid leptospiral entry into the circulation, dissemination, and further infection by impairing healing. LigB also binds fibroblast fibronectin and type III collagen, two proteins prevalent in wound repair, thus potentially enhancing leptospiral adhesion to skin openings. LigA or LigB expression by transformation of a nonpathogenic saprophyte, L. biflexa, enhances bacterial adhesion to fibrinogen. Our results suggest that by binding homeostatic proteins found in cutaneous wounds, LigB could facilitate leptospirosis transmission. Both fibronectin and fibrinogen binding have been mapped to an overlapping domain in LigB comprising repeats 9-11, with repeat 11 possibly enhancing binding by a conformational effect. Leptospirosis

  17. Production and characterization of monoclonal antibodies to the edta extract of Leptospira interrogans, serovar icterohaemorrhagiae

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    Lilian Terezinha de Queiroz Leite

    1996-10-01

    Full Text Available Monoclonal antibodies (MABs ivere produced against an etbylenediaminetetraacetate (EDTA extract of Leptospira interrogans serovar icterohaemorrhagiae being characterized by gel precipitation as IgM and IgG (IgGl and IgG2b. The EDTA extract was detected as several bands by silver staining in SDS-PAGE. In the Western blot the bands around 20 KDa reacted with a monoclonal antibody, 47B4D6, and was oxidized by periodate and was not digested by pronase, suggesting that the determinant is of carbohydrate nature, lmmunocytochemistry, using colloidal gold labeling, showed that an EDTA extract determinant recognized by monoclonal antibody 47B4D6, is localized under the outer envelope of serovar icterohaemorrhagiae. Hoe AIAB raised against the EDTA extract was not able to protect hamsters from lethal challenge with virulent homologous leptospires.Anticorpos monoclonais (AcM foram produzidos contra o extrato EDTA obtido de Leptospira interrogans, sorovar icterohaemorrhagiae. Pelo teste de precipitação foram caracterizados como IgM e IgG (IgGl e IgG2. A eletroforese em gel de poliacrilamida do extrato EDTA revelou diversas bandas quando corada pela prata. No "Western blot", as bandas em torno de 20 kDa reagiram com o AcM 47B4D6, foram oxidadas pelo periodato e não digeridas pela pronase, sugerindo que o determinante é de natureza carboidrato. O determinante reconhecido pelo AcM 47B4D6 estã localizado sob o envelope externo como revelado pela imunocitoquímica usando marcação com ouro coloidal. O AcM contra extrato EDTA do sorovar icterohaemorrahagiae não protegeu hamsters quando inoculados com lepstopira homóloga virulenta.

  18. Identification and partial characterization of a novel hemolysin from Leptospira interrogans serovar lai.

    Science.gov (United States)

    Lee, S H; Kim, K A; Park, Y G; Seong, I W; Kim, M J; Lee, Y J

    2000-08-22

    It has been suggested that leptospiral hemolysins are important in the virulence and pathogenesis of leptospirosis. We have isolated an Escherichia coli clone carrying the 7.8kb DNA insert from a genomic library of Leptospira interrogans serovar lai by plaque hybridization using a sequence derived from the sphingomyelinase C gene (sphA) of L. borgpetersenii. The clone showed a clear beta-hemolytic zone on sheep blood agar and high hemolytic activities on both human and sheep erythrocytes in liquid assays. The clone carried at least two genes responsible for the hemolytic activities, encoded by two open reading frames of 1662 and 816 nucleotides, which are named sphH and hap-1 (hemolysis associated protein-1), respectively. The SphH showed 75% homology to the SphA at the amino acid level, and the Hap-1 showed no significant homology in major databases. Interestingly, however, E. coli cells harboring sphH did not show sphingomyelinase or phospholipase activities. Moreover, SphH-mediated hemolysis was osmotically protected by polyethylene glycol 5000, suggesting that the hemolysis is likely to be caused by pore formation on the membrane. The SphH was successfully expressed in E. coli as a histidine (His)-SphH fusion protein. Both sphH and hap-1 were highly conserved among the Leptospira species, except for the absence of sphH in non-pathogenic L. biflexa serovar patoc. We concluded that the SphH is a novel hemolysin of a pathogenic Leptospira species, which may be a putative pore-forming protein.

  19. A model system for studying the transcriptomic and physiological changes associated with mammalian host-adaptation by Leptospira interrogans serovar Copenhageni.

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    Melissa J Caimano

    2014-03-01

    Full Text Available Leptospirosis, an emerging zoonotic disease with worldwide distribution, is caused by spirochetes belonging to the genus Leptospira. More than 500,000 cases of severe leptospirosis are reported annually, with >10% of these being fatal. Leptospires can survive for weeks in suitably moist conditions before encountering a new host. Reservoir hosts, typically rodents, exhibit little to no signs of disease but shed large numbers of organisms in their urine. Transmission occurs when mucosal surfaces or abraded skin come into contact with infected urine or urine-contaminated water or soil. In humans, leptospires can cause a variety of clinical manifestations, ranging from asymptomatic or mild fever to severe icteric (Weil's disease and pulmonary haemorrhage. Currently, little is known about how Leptospira persist within a reservoir host. Prior in vitro studies have suggested that leptospires alter their transcriptomic and proteomic profiles in response to environmental signals encountered during mammalian infection. However, no study has examined gene expression by leptospires within a mammalian host-adapted state. To obtain a more faithful representation of how leptospires respond to host-derived signals, we used RNA-Seq to compare the transcriptome of L. interrogans cultivated within dialysis membrane chambers (DMCs implanted into the peritoneal cavities of rats with that of organisms grown in vitro. In addition to determining the relative expression levels of "core" housekeeping genes under both growth conditions, we identified 166 genes that are differentially-expressed by L. interrogans in vivo. Our analyses highlight physiological aspects of host adaptation by leptospires relating to heme uptake and utilization. We also identified 11 novel non-coding transcripts that are candidate small regulatory RNAs. The DMC model provides a facile system for studying the transcriptional and antigenic changes associated with mammalian host

  20. Characterization of Three Novel Adhesins of Leptospira interrogans

    Science.gov (United States)

    Siqueira, Gabriela H.; Atzingen, Marina V.; Alves, Ivy J.; de Morais, Zenaide M.; Vasconcellos, Silvio A.; Nascimento, Ana L. T. O.

    2013-01-01

    We report cloning, expression, purification, and characterization of three predicted leptospiral membrane proteins (LIC11360, LIC11009, and LIC11975). In silico analysis and proteinase K accessibility data suggest that these proteins might be surface exposed. We show that proteins encoded by LIC11360, LIC11009 and LIC11975 genes interact with laminin in a dose-dependent and saturable manner. The proteins are referred to as leptospiral surface adhesions 23, 26, and 36 (Lsa23, Lsa26, and Lsa36), respectively. These proteins also bind plasminogen and generate active plasmin. Attachment of Lsa23 and Lsa36 to fibronectin occurs through the involvement of the 30-kDa and 70-kDa heparin-binding domains of the ligand. Dose-dependent, specific-binding of Lsa23 to the complement regulator C4BP and to a lesser extent, to factor H, suggests that this protein may interfere with the complement cascade pathways. Leptospira spp. may use these interactions as possible mechanisms during the establishment of infection. PMID:23958908

  1. Kinetics of Leptospira interrogans infection in hamsters after intradermal and subcutaneous challenge.

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    Mariana L Coutinho

    2014-11-01

    Full Text Available Leptospirosis is a zoonosis caused by highly motile, helically shaped bacteria that penetrate the skin and mucous membranes through lesions or abrasions, and rapidly disseminate throughout the body. Although the intraperitoneal route of infection is widely used to experimentally inoculate hamsters, this challenge route does not represent a natural route of infection.Here we describe the kinetics of disease and infection in hamster model of leptospirosis after subcutaneous and intradermal inoculation of Leptospira interrogans serovar Copenhageni, strain Fiocruz L1-130. Histopathologic changes in and around the kidney, including glomerular and tubular damage and interstitial inflammatory changes, began on day 5, and preceded deterioration in renal function as measured by serum creatinine. Weight loss, hemoconcentration, increased absolute neutrophil counts (ANC in the blood and hepatic dysfunction were first noted on day 6. Vascular endothelial growth factor, a serum marker of sepsis severity, became elevated during the later stages of infection. The burden of infection, as measured by quantitative PCR, was highest in the kidney and peaked on day 5 after intradermal challenge and on day 6 after subcutaneous challenge. Compared to subcutaneous challenge, intradermal challenge resulted in a lower burden of infection in both the kidney and liver on day 6, lower ANC and less weight loss on day 7.The intradermal and subcutaneous challenge routes result in significant differences in the kinetics of dissemination and disease after challenge with L. interrogans serovar Copenhageni strain Fiocruz L1-130 at an experimental dose of 2×106 leptospires. These results provide new information regarding infection kinetics in the hamster model of leptospirosis.

  2. Role of 72 kDa protein of Leptospira interrogans as a diagnostic marker in acute leptospirosis

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    M Riazi

    2014-01-01

    Full Text Available Background & objectives: Leptospirosis is a widespread zoonotic disease and a public health problem, particularly in tropical and subtropical countries. Varied clinical manifestations of the disease frequently lead to misdiagnosis resulting in life-threatening multi-organ complications. Therefore, early laboratory investigation using an appropriate diagnostic approach is crucial. In the present study, a potential protein marker was identified and evaluated for its usefulness in the serodiagnosis of acute leptospirosis. Methods: Leptospira interrogans serovar Icterohaemorrhagiae (L44, which represents a commonly prevalent serovar in Malaysia, was cultivated for preparation of sequential protein extract (SEQ. SDS-PAGE and immunoblotting were performed with a serum panel comprising confirmed cases of leptospirosis and controls (n=42 each. Identification and characterization of the highest scoring protein from the antigenic band was performed. Subsequently based on the nucleotide coding sequence of the protein, the corresponding recombinant protein was custom-produced. It was then evaluated for sensitivity and specificity by testing against 20 serum samples from leptospirosis patients and 32 from controls. Results: Among the antigenic components, a 72kDa protein band demonstrated significant sensitivity (83.3% and specificity (95.2% for the detection of specific anti-leptospiral IgM antibodies. The protein was identified by mass-spectrometry analysis as heat shock protein DnaK of L. interrogans. Recombinant form of the protein (r72SEQ showed 85 per cent sensitivity and 81 per cent specificity for the detection of specific anti-leptospiral IgM antibodies. Interpretation & conclusions: The findings of our study indicate that a protein (72kDa of L. interrogans has the potential utility of being used for the diagnosis of acute leptospirosis. Further studies need to be done to confirm these findings.

  3. Crystallization and preliminary X-ray diffraction studies of ferredoxin reductase from Leptospira interrogans

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Alessandro S.; Ferrarezi, Thiago [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970 (Brazil); Catalano-Dupuy, Daniela L.; Ceccarelli, Eduardo A. [Facultad de Ciencias Bioquímicas y Farmacéuticas, Molecular Biology Division, Instituto de Biología Molecular y Celular de Rosario (IBR), CONICET, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario (Argentina); Polikarpov, Igor, E-mail: ipolikarpov@if.sc.usp.br [Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador Saocarlense 400, São Carlos, SP, 13560-970 (Brazil)

    2006-07-01

    Crystals adequate for X-ray diffraction analysis have been prepared from L. interrogans ferredoxin-NADP{sup +} reductase. Ferredoxin-NADP{sup +} reductase (FNR) is an FAD-containing enzyme that catalyzes electron transfer between NADP(H) and ferredoxin. Here, results are reported of the recombinant expression, purification and crystallization of FNR from Leptospira interrogans, a parasitic bacterium of animals and humans. The L. interrogans FNR crystals belong to a primitive monoclinic space group and diffract to 2.4 Å resolution at a synchrotron source.

  4. A dominant clone of Leptospira interrogans associated with an outbreak of human leptospirosis in Thailand.

    Science.gov (United States)

    Thaipadungpanit, Janjira; Wuthiekanun, Vanaporn; Chierakul, Wirongrong; Smythe, Lee D; Petkanchanapong, Wimol; Limpaiboon, Roongrueng; Apiwatanaporn, Apichat; Slack, Andrew T; Suputtamongkol, Yupin; White, Nicholas J; Feil, Edward J; Day, Nicholas P J; Peacock, Sharon J

    2007-10-31

    A sustained outbreak of leptospirosis occurred in northeast Thailand between 1999 and 2003, the basis for which was unknown. A prospective study was conducted between 2000 and 2005 to identify patients with leptospirosis presenting to Udon Thani Hospital in northeast Thailand, and to isolate the causative organisms from blood. A multilocus sequence typing scheme was developed to genotype these pathogenic Leptospira. Additional typing was performed for Leptospira isolated from human cases in other Thai provinces over the same period, and from rodents captured in the northeast during 2004. Sequence types (STs) were compared with those of Leptospira drawn from a reference collection. Twelve STs were identified among 101 isolates from patients in Udon Thani. One of these (ST34) accounted for 77 (76%) of isolates. ST34 was Leptospira interrogans, serovar Autumnalis. 86% of human Leptospira isolates from Udon Thani corresponded to ST34 in 2000/2001, but this figure fell to 56% by 2005 as the outbreak waned (p = 0.01). ST34 represented 17/24 (71%) of human isolates from other Thai provinces, and 7/8 (88%) rodent isolates. By contrast, 59 STs were found among 76 reference strains, indicating a much more diverse population genetic structure; ST34 was not identified in this collection. Development of an MLST scheme for Leptospira interrogans revealed that a single ecologically successful pathogenic clone of L. interrogans predominated in the rodent population, and was associated with a sustained outbreak of human leptospirosis in Thailand.

  5. A dominant clone of Leptospira interrogans associated with an outbreak of human leptospirosis in Thailand.

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    Janjira Thaipadungpanit

    2007-10-01

    Full Text Available A sustained outbreak of leptospirosis occurred in northeast Thailand between 1999 and 2003, the basis for which was unknown.A prospective study was conducted between 2000 and 2005 to identify patients with leptospirosis presenting to Udon Thani Hospital in northeast Thailand, and to isolate the causative organisms from blood. A multilocus sequence typing scheme was developed to genotype these pathogenic Leptospira. Additional typing was performed for Leptospira isolated from human cases in other Thai provinces over the same period, and from rodents captured in the northeast during 2004. Sequence types (STs were compared with those of Leptospira drawn from a reference collection. Twelve STs were identified among 101 isolates from patients in Udon Thani. One of these (ST34 accounted for 77 (76% of isolates. ST34 was Leptospira interrogans, serovar Autumnalis. 86% of human Leptospira isolates from Udon Thani corresponded to ST34 in 2000/2001, but this figure fell to 56% by 2005 as the outbreak waned (p = 0.01. ST34 represented 17/24 (71% of human isolates from other Thai provinces, and 7/8 (88% rodent isolates. By contrast, 59 STs were found among 76 reference strains, indicating a much more diverse population genetic structure; ST34 was not identified in this collection.Development of an MLST scheme for Leptospira interrogans revealed that a single ecologically successful pathogenic clone of L. interrogans predominated in the rodent population, and was associated with a sustained outbreak of human leptospirosis in Thailand.

  6. Leptospira interrogans at the human-wildlife interface in northern Botswana: a newly identified public health threat.

    Science.gov (United States)

    Jobbins, S E; Sanderson, C E; Alexander, K A

    2014-03-01

    Leptospirosis is the most widespread zoonosis in the world. In northern Botswana, humans live in close proximity to a diversity of wildlife and peridomestic rodents and may be exposed to a variety of zoonotic pathogens. Little is known regarding the occurrence and epidemiology of L. interrogans in Africa despite the recognized global importance of this zoonotic disease and the threat it poses to public health. In Botswana, banded mongooses (Mungos mungo) live in close proximity to humans across protected and unprotected landscapes and may be a useful sentinel species for assessing the occurrence of zoonotic organisms, such as L. interrogans. We utilized PCR to screen banded mongoose kidneys for leptospiral DNA and identified 41.5% prevalence of renal carriage of L. interrogans (exact binomial 95% CI 27.7-56.7%, n = 41). Renal carriage was also detected in one Selous' mongoose (Paracynictis selousi). This is the first published confirmation of carriage of L. interrogans in either species. This is also the first report of L. interrogans occurrence in northern Botswana and the only report of this organism in a wildlife host in the country. Pathogenic Leptospira are usually transmitted indirectly to humans through soil or water contaminated with infected urine. Other avenues, such as direct contact between humans and wildlife, as well as consumption of mongooses and other wildlife as bushmeat, may pose additional exposure risk and must be considered in public health management of this newly identified zoonotic disease threat. There is a critical need to characterize host species involvement and pathogen transmission dynamics, including human-wildlife interactions that may increase human exposure potential and infection risk. We recommend that public health strategy be modified to include sensitization of medical practitioners to the presence of L. interrogans in the region, the potential for human infection, and implementation of clinical screening. This study

  7. Production of reactive oxygen species and expression of inducible nitric oxide synthase in rat isolated Kupffer cells stimulated by Leptospira interrogans and Borrelia burgdorferi

    Institute of Scientific and Technical Information of China (English)

    Antonella Marangoni; Silvia Accardo; Rita Aldini; Massimo Guardigli; Francesca Cavrini; Vittorio Sambri; Marco Montagnani; Aldo Roda; Roberto Cevenini

    2006-01-01

    AIM: To evaluate the production of reactive oxygen species (ROS) and the expression of indudble nitric oxide synthase (iNOS) in rat isolated Kupffer cells (KCs) stimulated by Leptospira interrogans and Borrelia burgdorferi.METHODS: Rat Kupffer cells were separated by perfusion of the liver with 0.05% collagenase, and purified by Percoll gradients. Purified Kupffer cells were tested in vitro with alive L.interogans and B. burgdorferi preparations. The production of ROS was determined by chemiluminescence, whereas iNOS protein expression was evaluated by Western blot assay using anti-iNOS antibodies.RESULTS: B. burgdorferi and to a less extent L. interrogans induced ROS production with a peak 35 min after infection. The chemiluminescence signal progressively diminished and was undetectable by 180 min of incubation. Leptospirae and borreliae induced an increased iNOS expression in Kupffer cells that peaked at 6 hours and was still evident 22 h after infection.CONCLUSION: Both genera of spirochetes induced ROS and iNOS production in rat Kupffer cells. Since the cause of liver damage both in leptospiral as well as in borrelial infections are still unknown, we suggest that leptospira and borrelia damage of the liver can be initially mediated by oxygen radicals, and is then maintained at least in part by nitric oxide.

  8. Transcriptional response of Leptospira interrogans to iron limitation and characterization of a PerR homolog

    Science.gov (United States)

    Leptospira interrogans is the causative agent of leptospirosis, a zoonosis of global significance. Iron is essential for growth of most bacterial species. Since availability of iron is low in the host, pathogens have evolved complex iron acquisition mechanisms to survive and establish infection. In ...

  9. Leptospira interrogans serovar hardjo in the kidneys and genital tracts of naturally infected sheep.

    Science.gov (United States)

    Cerri, D; Nuvoloni, R; Ebani, V; Pedrini, A; Mani, P; Andreani, E; Farina, R

    1996-04-01

    A bacteriological study was carried out to identify possible renal and/or genital carriers of Leptospira interrogans serovar hardjo. L. hardjo was found at slaughter in the kidneys of three seropositive ewes, but not in uterus or salpinges of these animals.

  10. Prediction and systematic study of protein-protein interaction networks of Leptospira interrogans

    Institute of Scientific and Technical Information of China (English)

    SUN Jingchun; XU Jinlin; CAO Jianping; LIU Qi; GUO Xiaokui; SHI Tieliu; LI Yixue

    2006-01-01

    Leptospira interrogans serovar Lai is a pathogenic bacterium that causes a spirochetal zoonosis in humans and some animals. With its complete genome sequence available, it is possible to analyze protein-protein interactions from a whole- genome standpoint. Here we combine four recently developed computational approaches (gene fusion method, gene neighbor method, phylogenetic profiles method, and operon method) to predict protein-pro- tein interaction networks of Leptospira interrogans strain Lai. Through comprehensive analysis on in- teractions among proteins of motility and chemotaxis system, signal transduction, lipopolysaccaride bio- synthesis and a series of proteins related to adhesion and invasion, we provided information for further studying on its pathogenic mechanism. In addition, we also assigned 203 previously uncharacterized proteins with possible functions based on the known functions of its interacting partners. This work is helpful for further investigating L. interrogans strain Lai.

  11. Isolation and characterization of Leptospira interrogans from pigs slaughtered in São Paulo State, Brazil Isolamento e caracterização de Leptospira interrogans de suínos abatidos no Estado de São Paulo, Brasil

    Directory of Open Access Journals (Sweden)

    Fabiana Miraglia

    2008-09-01

    Full Text Available With the aim of isolating Leptospira spp., blood serum, kidney, liver and genital tract of 137 female swine (40 sows and 97 gilts and also urine samples from 22 sows were collected in a slaughterhouse in the State of São Paulo, from April 2003 to August 2004. Four isolates were obtained from animals that presented microagglutination test (MAT titers > 100 for the serovar Pomona and one was obtained from an animal negative by MAT in which Leptospira was isolated from the liver and reproductive tract. The presence of leptospiral DNA was investigated by PCR, and positive results were found in kidneys of 11 females, liver of two, genital tract of two and urine of one of them. Nephrosis, interstitial multifocal nephritis, moderate to severe changing, hyalines cylinders and hemorrhagic focuses, hepatic and uterine horns congestion were histological lesions observed in higher frequency in animals positive for leptospira. The silver impregnation (Warthin Starry confirmed the presence of spirochetes in renal tubules of four females with positive leptospira cultures from kidneys. The serogroup of the five isolates was identified as Pomona by cross agglutination with reference polyclonal antibodies. Molecular characterization of the isolates was carried out by variable-number tandem-repeats analysis. All the isolates revealed a pattern distinct from the L. interrogans Pomona type strain, but identical to a previously identified pattern from strains isolated in Argentina belonging to serovar Pomona.Amostras de soro sanguíneo, rim, fígado e trato genital de 137 fêmeas suínas (40 matrizes e 97 marrãs e de urina de 22 matrizes foram colhidas em abatedouro no Estado de São Paulo, no período de abril de 2003 a agosto de 2004 tendo como objetivo o isolamento de Leptospira spp. Quatro estirpes foram isoladas de animais que apresentaram títulos, no teste de soroaglutinação microscópica (SAM > 100, para o sorovar Pomona e de um animal, não reagente na

  12. Data on Leptospira interrogans sv Pomona infection in Meat Workers in New Zealand.

    Science.gov (United States)

    Pittavino, M; Dreyfus, A; Heuer, C; Benschop, J; Wilson, P; Collins-Emerson, J; Torgerson, P R; Furrer, R

    2017-08-01

    The data presented in this article are related to the research article entitled "Comparison between Generalized Linear Modelling and Additive Bayesian Network; Identification of Factors associated with the Incidence of Antibodies against Leptospira interrogans sv Pomona in Meat Workers in New Zealand" (Pittavino et al., 2017) [5]. A prospective cohort study was conducted in four sheep slaughtering abattoirs in New Zealand (NZ) (Dreyfus et al., 2015) [1]. Sera were collected twice a year from 384 meat workers and tested by Microscopic Agglutination for Leptospira interrogans sv Pomona (Pomona) infection, one of the most common Leptospira serovars in humans in NZ. This article provides an extended analysis of the data, illustrating the different steps of a multivariable (i.e. generalized linear model) and especially a multivariate tool based on additive Bayesian networks (ABN) modelling.

  13. Evaluation of Pathogenic Serovars of Leptospira Interrogans in Dairy Cattle Herds of Shahrekord by PCR

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    HR Shahbazkia

    2011-12-01

    Full Text Available Background and objectives: Leptospirosis is an important zoonotic disease caused by Leptospira interrogans. Leptospirosis leads to economical losses in dairy farm industry. The objective of this study was to evaluate the pathogenic serovars of Leptospira interrogans in dairy cattle herds of Shahrekord by PCR.Materials and Methods: Two hundred samples (100 urine and 100 blood were collected from 100 cows randomly and delivered to the laboratory. Samples were stored at -20 °C. DNA was extracted and purified from the plasma and urine samples and concentrated on diatoms in the presence of guanidine thiocyanate (GuSCN. PCR products were detected and identified as Leptospira by ilumination of the expected size of DNA bands after staining of the agarose gel with ethidium bromide gels. PCR products were purified and sequenced.Results: The results showed that 28% of urine samples and 23% of plasma samples were contaminated. The major serotypes were Icterohaemorrhagiae (50% and Pomona (37.5%. The urine samples of 17 cows were positive for Leptospira without positive plasma samples. This indicated that these cows are reservoirs in dairy herds of Shahrekord and dangerous for human health. The plasma samples of twelve cows were positive for Leptospira without positive urine samples.Conclusions: Leptospira serotypes can be maintained in relatively dry regions and must be considered when dealing with leptospirosis in dairy farms of Shahrekord and human health.

  14. Data on Leptospira interrogans sv Pomona infection in Meat Workers in New Zealand

    Directory of Open Access Journals (Sweden)

    M. Pittavino

    2017-08-01

    A prospective cohort study was conducted in four sheep slaughtering abattoirs in New Zealand (NZ (Dreyfus et al., 2015 [1]. Sera were collected twice a year from 384 meat workers and tested by Microscopic Agglutination for Leptospira interrogans sv Pomona (Pomona infection, one of the most common Leptospira serovars in humans in NZ. This article provides an extended analysis of the data, illustrating the different steps of a multivariable (i.e. generalized linear model and especially a multivariate tool based on additive Bayesian networks (ABN modelling.

  15. Fine Mapping of the Interaction between C4b-Binding Protein and Outer Membrane Proteins LigA and LigB of Pathogenic Leptospira interrogans.

    Science.gov (United States)

    Breda, Leandro C D; Hsieh, Ching-Lin; Castiblanco Valencia, Mónica M; da Silva, Ludmila B; Barbosa, Angela S; Blom, Anna M; Chang, Yung-Fu; Yung-Fu, Chang; Isaac, Lourdes

    2015-01-01

    The complement system consists of more than 40 proteins that participate in the inflammatory response and in pathogen killing. Complement inhibitors are necessary to avoid the excessive consumption and activation of this system on host cells. Leptospirosis is a worldwide zoonosis caused by spirochetes from the genus Leptospira. Pathogenic leptospires are able to escape from complement activation by binding to host complement inhibitors Factor H [FH] and C4b-binding protein (C4BP) while non-pathogenic leptospires are rapidly killed in the presence of fresh serum. In this study, we demonstrate that complement control protein domains (CCP) 7 and 8 of C4BP α-chain interact with the outer membrane proteins LcpA, LigA and LigB from the pathogenic leptospire L. interrogans. The interaction between C4BP and LcpA, LigA and LigB is sensitive to ionic strength and inhibited by heparin. We fine mapped the LigA and LigB domains involved in its binding to C4BP and heparin and found that both interactions are mediated through the bacterial immunoglobulin-like (Big) domains 7 and 8 (LigA7-8 and LigB7-8) of both LigA and LigB and also through LigB9-10. Therefore, C4BP and heparin may share the same binding sites on Lig proteins.

  16. Identification of seroreactive proteins of Leptospira interrogans serovar copenhageni using a high-density protein microarray approach.

    Science.gov (United States)

    Lessa-Aquino, Carolina; Borges Rodrigues, Camila; Pablo, Jozelyn; Sasaki, Rie; Jasinskas, Algis; Liang, Li; Wunder, Elsio A; Ribeiro, Guilherme S; Vigil, Adam; Galler, Ricardo; Molina, Douglas; Liang, Xiaowu; Reis, Mitermayer G; Ko, Albert I; Medeiros, Marco Alberto; Felgner, Philip L

    2013-01-01

    Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Leptospira interrogans proteome and investigated the IgG response from 274 individuals, including 80 acute-phase, 80 convalescent-phase patients and 114 healthy control subjects from regions with endemic, high endemic, and no endemic transmission of leptospirosis. A nitrocellulose line blot assay was performed to validate the accuracy of the protein microarray results. We found 16 antigens that can discriminate between acute cases and healthy individuals from a region with high endemic transmission of leptospirosis, and 18 antigens that distinguish convalescent cases. Some of the antigens identified in this study, such as LipL32, the non-identical domains of the Lig proteins, GroEL, and Loa22 are already known to be recognized by sera from human patients, thus serving as proof-of-concept for the serodiagnostic antigen discovery approach. Several novel antigens were identified, including the hypothetical protein LIC10215 which showed good sensitivity and specificity rates for both acute- and convalescent-phase patients. Our study is the first large-scale evaluation of immunodominant antigens associated with naturally acquired leptospiral infection, and novel as well as known serodiagnostic leptospiral antigens that are recognized by antibodies in the sera of leptospirosis cases were identified. The novel antigens identified here may have potential use in both the development of new tests and the improvement of currently available assays for diagnosing this neglected tropical disease. Further

  17. Identification of seroreactive proteins of Leptospira interrogans serovar copenhageni using a high-density protein microarray approach.

    Directory of Open Access Journals (Sweden)

    Carolina Lessa-Aquino

    Full Text Available Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease.In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Leptospira interrogans proteome and investigated the IgG response from 274 individuals, including 80 acute-phase, 80 convalescent-phase patients and 114 healthy control subjects from regions with endemic, high endemic, and no endemic transmission of leptospirosis. A nitrocellulose line blot assay was performed to validate the accuracy of the protein microarray results.We found 16 antigens that can discriminate between acute cases and healthy individuals from a region with high endemic transmission of leptospirosis, and 18 antigens that distinguish convalescent cases. Some of the antigens identified in this study, such as LipL32, the non-identical domains of the Lig proteins, GroEL, and Loa22 are already known to be recognized by sera from human patients, thus serving as proof-of-concept for the serodiagnostic antigen discovery approach. Several novel antigens were identified, including the hypothetical protein LIC10215 which showed good sensitivity and specificity rates for both acute- and convalescent-phase patients.Our study is the first large-scale evaluation of immunodominant antigens associated with naturally acquired leptospiral infection, and novel as well as known serodiagnostic leptospiral antigens that are recognized by antibodies in the sera of leptospirosis cases were identified. The novel antigens identified here may have potential use in both the development of new tests and the improvement of currently available assays for diagnosing this neglected tropical disease

  18. Leptospira interrogans induces uterine inflammatory responses and abnormal expression of extracellular matrix proteins in dogs.

    Science.gov (United States)

    Wang, Wei; Gao, Xuejiao; Guo, Mengyao; Zhang, Wenlong; Song, Xiaojing; Wang, Tiancheng; Zhang, Zecai; Jiang, Haichao; Cao, Yongguo; Zhang, Naisheng

    2014-10-01

    Leptospira interrogans (L. interrogans), a worldwide zoonosis, infect humans and animals. In dogs, four syndromes caused by leptospirosis have been identified: icteric, hemorrhagic, uremic (Stuttgart disease) and reproductive (abortion and premature or weak pups), and also it caused inflammation. Extracellular matrix (ECM) is a complex mixture of matrix molecules that is crucial to the reproduction. Both inflammatory response and ECM are closed relative to reproductive. The aim of this study was to clarify how L. interrogans affected the uterus of dogs, by focusing on the inflammatory responses, and ECM expression in dogs uterine tissue infected by L. interrogans. In the present study, 27 dogs were divided into 3 groups, intrauterine infusion with L. interrogans, to make uterine infection, sterile EMJH, and normal saline as a control, respectively. The uteruses were removed by surgical operation in 10, 20, and 30 days, respectively. The methods of histopathological analysis, ELISA, Western blot and qPCR were used. The results showed that L. interrogans induced significantly inflammatory responses, which were characterized by inflammatory cellular infiltration and high expression levels of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in uterine tissue of these dogs. Furthermore, L. interrogans strongly down-regulated the expression of ECM (collagens (CL) IV, fibronectins (FN) and laminins (LN)) in mRNA and protein levels. These data indicated that strongly inflammatory responses, and abnormal regulation of ECM might contribute to the proliferation of dogs infected by L. interrogans.

  19. Preliminary identification of secreted proteins by Leptospira interrogans serovar Kennewicki strain Pomona Fromm

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    Ricardi, L.M.P.; Portaro, F.C.; Abreu, P.A.E.; Barbosa, A.S. [Instituto Butantan, Sao Paulo, SP (Brazil); Morais, Z.M.; Vasconcellos, S.A. [Universidade de Sao Paulo (USP), SP (Brazil)

    2012-07-01

    Full text: This project aimed to identify secreted proteins by pathogenic Leptospira interrogans serovar Kennewicki strain Pomona Fromm (LPF) by proteomic analyses. The strain LPF, whose virulence was maintained by passages in hamsters, were cultured in EMJH medium. The supernatants were centrifuged, dialyzed and subjected to lyophilization. Protein samples were resolved first by IEF at pH 3 to 10, immobilized pH gradient 13-cm strips. Strips were then processed for the second-dimension separation on SDS-polyacrylamide gels. Proteins from gel spots were subjected to reduction, cysteine-alkylation, and in-gel tryptic digestion, and analyzed by LC/MS/MS spectrometry. Liquid chromatography-based separation followed by automated tandem mass spectrometry was also used to identify secreted proteins. In silico analyses were performed using the PSORTbV.3.0 program and SignalP server. One major obstacle to secretome studies is the difficulty to obtain extracts of secreted proteins without citoplasmatic contamination. In addition, the extraction of low concentration proteins from large volumes of culture media, which are rich in salts, BSA and other compounds, frequently interfere with most proteomics techniques. For these reasons, several experimental approaches were used to optimize the protocol applied. In spite of this fact, our analysis resulted in the identification of 200 proteins with high confidence. Only 5 of 63 secreted proteins predicted by in silico analysis were found. Other classes identified included proteins that possess signal peptide but whose cellular localization prediction is unknown or may have multiple localization sites, and proteins that lack signal peptide and are thus thought to be secreted via non conventional mechanisms or resulting from cytoplasmic contamination by cell lysis. Many of these are hypothetical proteins with no putative conserved domains detected. To our knowledge, this is the first study to identify secreted proteins by

  20. Whole Genome Sequencing Allows Better Understanding of the Evolutionary History of Leptospira interrogans Serovar Hardjo

    Science.gov (United States)

    Llanes, Alejandro; Restrepo, Carlos Mario; Rajeev, Sreekumari

    2016-01-01

    The genome of a laboratory-adapted strain of Leptospira interrogans serovar Hardjo was sequenced and analyzed. Comparison of the sequenced genome with that recently published for a field isolate of the same serovar revealed relatively high sequence conservation at the nucleotide level, despite the different biological background of both samples. Conversely, comparison of both serovar Hardjo genomes with those of L. borgpetersenii serovar Hardjo showed extensive differences between the corresponding chromosomes, except for the region occupied by their rfb loci. Additionally, comparison of the serovar Hardjo genomes with those of different L. interrogans serovars allowed us to detect several genomic features that may confer an adaptive advantage to L. interrogans serovar Hardjo, including a possible integrated plasmid and an additional copy of a cluster encoding a membrane transport system known to be involved in drug resistance. A phylogenomic strategy was used to better understand the evolutionary position of the Hardjo serovar among L. interrogans serovars and other Leptospira species. The proposed phylogeny supports the hypothesis that the presence of similar rfb loci in two different species may be the result of a lateral gene transfer event. PMID:27442015

  1. Medio EMJH modificado para el cultivo de Leptospira interrogans serogrupo Ballum Modified EMJH medium for cultivation of Leptospira interrogans serogroup Ballum

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    A. González

    2006-04-01

    Full Text Available El serogrupo Ballum agrupa cepas de crecimiento fastidioso, con requerimientos nutricionales más exigentes que otras cepas patógenas de Leptospira. Fue evaluada la influencia de 37 compuestos nutricionales sobre el crecimiento de Leptospira interrogans serogrupo Ballum, tomando como base para el estudio al medio sintético EMJH. El crecimiento microbiano fue estimado espectrofotométricamente y por conteo directo en cámara de Petroff-Hausser. La estabilidad de la virulencia fue evaluada en hamsters mediante el cálculo de la dosis letal media. La estabilidad de la antigenicidad fue evaluada mediante Western blotting con antisuero policlonal específico. Bajo condiciones de cultivo controladas se logró triplicar los rendimientos de biomasa comúnmente obtenidos en el medio EMJH sin afectación de la virulencia y antigenicidad tras el incremento de la concentración de Tween 80 y la incorporación de acetato de sodio y extracto de carne. El incremento de la concentración de al menos 6 componentes del EMJH o la incorporación de una variedad de nuevos nutrientes no estimularon apreciablemente los rendimientos de biomasa o la velocidad específica de crecimiento del microorganismo. Los resultados obtenidos permiten disponer de un medio de cultivo enriquecido capaz de sustentar elevados rendimientos de biomasa de este serogrupo exigente de mayor circulación en humanos en Cuba.Strains within the Ballum serogroup of spirochete Leptospira show fastidious growth with more exigent nutritional requirements than those of other Leptospira pathogenic strains. The influence of 37 nutritional compounds on the growth of Leptospira interrogans serogroup Ballum was investigated employing the synthetic EMJH medium as the base for the study. Microbial growth was estimated spectrophotometrically and direct counts were performed with a Petroff-Hausser counting chamber. Virulence stability was evaluated by calculating the mean lethal dose in hamsters

  2. In silico and microarray-based genomic approaches to identifying potential vaccine candidates against Leptospira interrogans

    Directory of Open Access Journals (Sweden)

    Jiang Xu-Cheng

    2006-11-01

    Full Text Available Abstract Background Currently available vaccines against leptospirosis are of low efficacy, have an unacceptable side-effect profile, do not induce long-term protection, and provide no cross-protection against the different serovars of pathogenic leptospira. The current major focus in leptospirosis research is to discover conserved protective antigens that may elicit longer-term protection against a broad range of Leptospira. There is a need to screen vaccine candidate genes in the genome of Leptospira interrogans. Results Bioinformatics, comparative genomic hybridization (CGH analysis and transcriptional analysis were used to identify vaccine candidates in the genome of L. interrogans serovar Lai strain #56601. Of a total of 4727 open reading frames (ORFs, 616 genes were predicted to encode surface-exposed proteins by P-CLASSIFIER combined with signal peptide prediction, α-helix transmembrane topology prediction, integral β-barrel outer membrane protein and lipoprotein prediction, as well as by retaining the genes shared by the two sequenced L. interrogans genomes and by subtracting genes with human homologues. A DNA microarray of L. interrogans strain #56601 was constructed for CGH analysis and transcriptome analysis in vitro. Three hundred and seven differential genes were identified in ten pathogenic serovars by CGH; 1427 genes had high transcriptional levels (Cy3 signal ≥ 342 and Cy5 signal ≥ 363.5, respectively. There were 565 genes in the intersection between the set encoding surface-exposed proteins and the set of 307 differential genes. The number of genes in the intersection between this set of 565 and the set of 1427 highly transcriptionally active genes was 226. These 226 genes were thus identified as putative vaccine candidates. The proteins encoded by these genes are not only potentially surface-exposed in the bacterium, but also conserved in two sequenced L. interrogans. Moreover, these genes are conserved among ten epidemic

  3. In vitro identification of novel plasminogen-binding receptors of the pathogen Leptospira interrogans.

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    Monica L Vieira

    Full Text Available BACKGROUND: Leptospirosis is a multisystem disease caused by pathogenic strains of the genus Leptospira. We have reported that Leptospira are able to bind plasminogen (PLG, to generate active plasmin in the presence of activator, and to degrade purified extracellular matrix fibronectin. METHODOLOGY/PRINCIPAL FINDINGS: We have now cloned, expressed and purified 14 leptospiral recombinant proteins. The proteins were confirmed to be surface exposed by immunofluorescence microscopy and were evaluated for their ability to bind plasminogen (PLG. We identified eight as PLG-binding proteins, including the major outer membrane protein LipL32, the previously published rLIC12730, rLIC10494, Lp29, Lp49, LipL40 and MPL36, and one novel leptospiral protein, rLIC12238. Bound PLG could be converted to plasmin by the addition of urokinase-type PLG activator (uPA, showing specific proteolytic activity, as assessed by its reaction with the chromogenic plasmin substrate, D-Val-Leu-Lys 4-nitroanilide dihydrochloride. The addition of the lysine analog 6-aminocaproic acid (ACA inhibited the protein-PLG interaction, thus strongly suggesting the involvement of lysine residues in plasminogen binding. The binding of leptospiral surface proteins to PLG was specific, dose-dependent and saturable. PLG and collagen type IV competed with LipL32 protein for the same binding site, whereas separate binding sites were observed for plasma fibronectin. CONCLUSIONS/SIGNIFICANCE: PLG-binding/activation through the proteins/receptors on the surface of Leptospira could help the bacteria to specifically overcome tissue barriers, facilitating its spread throughout the host.

  4. Leptospira interrogans serovar Copenhageni Harbors Two lexA Genes Involved in SOS Response

    Science.gov (United States)

    Fonseca, Luciane S.; da Silva, Josefa B.; Milanez, Juliana S.; Monteiro-Vitorello, Claudia B.; Momo, Leonardo; de Morais, Zenaide M.; Vasconcellos, Silvio A.; Marques, Marilis V.; Ho, Paulo L.; da Costa, Renata M. A.

    2013-01-01

    Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2) one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN 5CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN 10TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence. PMID:24098496

  5. Leptospira interrogans serovar copenhageni harbors two lexA genes involved in SOS response.

    Science.gov (United States)

    Fonseca, Luciane S; da Silva, Josefa B; Milanez, Juliana S; Monteiro-Vitorello, Claudia B; Momo, Leonardo; de Morais, Zenaide M; Vasconcellos, Silvio A; Marques, Marilis V; Ho, Paulo L; da Costa, Renata M A

    2013-01-01

    Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2) one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN 5CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN10TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence.

  6. Leptospira interrogans serovar copenhageni harbors two lexA genes involved in SOS response.

    Directory of Open Access Journals (Sweden)

    Luciane S Fonseca

    Full Text Available Bacteria activate a regulatory network in response to the challenges imposed by DNA damage to genetic material, known as the SOS response. This system is regulated by the RecA recombinase and by the transcriptional repressor lexA. Leptospira interrogans is a pathogen capable of surviving in the environment for weeks, being exposed to a great variety of stress agents and yet retaining its ability to infect the host. This study aims to investigate the behavior of L. interrogans serovar Copenhageni after the stress induced by DNA damage. We show that L. interrogans serovar Copenhageni genome contains two genes encoding putative LexA proteins (lexA1 and lexA2 one of them being potentially acquired by lateral gene transfer. Both genes are induced after DNA damage, but the steady state levels of both LexA proteins drop, probably due to auto-proteolytic activity triggered in this condition. In addition, seven other genes were up-regulated following UV-C irradiation, recA, recN, dinP, and four genes encoding hypothetical proteins. This set of genes is potentially regulated by LexA1, as it showed binding to their promoter regions. All these regions contain degenerated sequences in relation to the previously described SOS box, TTTGN 5CAAA. On the other hand, LexA2 was able to bind to the palindrome TTGTAN10TACAA, found in its own promoter region, but not in the others. Therefore, the L. interrogans serovar Copenhageni SOS regulon may be even more complex, as a result of LexA1 and LexA2 binding to divergent motifs. New possibilities for DNA damage response in Leptospira are expected, with potential influence in other biological responses such as virulence.

  7. Development of the leptospirosis by experimental infection in hamsters (Mesocricetus auratus with Leptospira interrogans serovar Canicola, strain LO4, by intact and scratched skin exposures

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    Carolina de Sousa Américo Batista

    2010-10-01

    Full Text Available The establishment and evolution of leptospirosis in hamster (Mesocricetus auratus by experimental infection with Leptospira interrogans serovar Canicola, LO4 strain, by intact and scratched skin exposures, having as control the intraperitoneal route, were evaluated. Hundred-twenty female hamsters distributed in two groups according to inoculation route (intact and scratched skin were used. Infectious inoculum was constituted by a pure culture of L. interrogans serovar Canicola (strain LO4, isolated from liver from a slaughtered swine in Londrina, Paraná state and typified by agglutinins adsortion technique with monoclonal antibody kit at the Royal Tropical Institute, Amsterdam, the Netherlands. The animals were observed twice a day during 21 days. Animals that died were necropsied and kidneys, liver, genital tract (uterus and ovaries and brain were aseptically collected. On the 21st post-inoculation day, surviving animals were euthanized. In these animals, serum samples were also collected by cardiac puncture to antileptospires agglutinins research using microscopic agglutination test (MAT. Fresh direct microscopy and microbiological culture were used for the detection of leptospires. Scratched skin route induced larger lethality when compared to intact skin route, with establishment and evolution of leptospirosis. On the other hand, intact skin route induced renal and/or genital carrier state more frequently. LO4 strain presented low immunogenic power, characterized by soroconversion at the MAT in only one inoculated animal.

  8. Identification of Leptospira interrogans phospholipase C as a novel virulence factor responsible for intracellular free calcium ion elevation during macrophage death.

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    Jing-Fang Zhao

    Full Text Available BACKGROUND: Leptospira-induced macrophage death has been confirmed to play a crucial role in pathogenesis of leptospirosis, a worldwide zoonotic infectious disease. Intracellular free Ca(2+ concentration ([Ca(2+]i elevation induced by infection can cause cell death, but [Ca(2+]i changes and high [Ca(2+]i-induced death of macrophages due to infection of Leptospira have not been previously reported. METHODOLOGY/PRINCIPAL FINDINGS: We first used a Ca(2+-specific fluorescence probe to confirm that the infection of L. interrogans strain Lai triggered a significant increase of [Ca(2+]i in mouse J774A.1 or human THP-1 macrophages. Laser confocal microscopic examination showed that the [Ca(2+]i elevation was caused by both extracellular Ca(2+ influx through the purinergic receptor, P2X7, and Ca(2+ release from the endoplasmic reticulum, as seen by suppression of [Ca(2+]i elevation when receptor-gated calcium channels were blocked or P2X7 was depleted. The LB361 gene product of the spirochete exhibited phosphatidylinositol phospholipase C (L-PI-PLC activity to hydrolyze phosphatidylinositol-4,5-bisphosphate (PIP2 into inositol-1,4,5-trisphosphate (IP3, which in turn induces intracellular Ca(2+ release from endoplasmic reticulum, with the Km of 199 µM and Kcat of 8.566E-5 S(-1. Secretion of L-PI-PLC from the spirochete into supernatants of leptospire-macrophage co-cultures and cytosol of infected macrophages was also observed by Western Blot assay. Lower [Ca(2+]i elevation was induced by infection with a LB361-deficient leptospiral mutant, whereas transfection of the LB361 gene caused a mild increase in [Ca(2+]i. Moreover, PI-PLCs (PI-PLC-β3 and PI-PLC-γ1 of the two macrophages were activated by phosphorylation during infection. Flow cytometric detection demonstrated that high [Ca(2+]i increases induced apoptosis and necrosis of macrophages, while mild [Ca(2+]i elevation only caused apoptosis. CONCLUSIONS/SIGNIFICANCE: This study demonstrated that L

  9. A highly stable plastidic-type ferredoxin-NADP(H reductase in the pathogenic bacterium Leptospira interrogans.

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    Daniela L Catalano-Dupuy

    Full Text Available Leptospira interrogans is a bacterium that is capable of infecting animals and humans, and its infection causes leptospirosis with a range of symptoms from flu-like to severe illness and death. Despite being a bacteria, Leptospira interrogans contains a plastidic class ferredoxin-NADP(H reductase (FNR with high catalytic efficiency, at difference from the bacterial class FNRs. These flavoenzymes catalyze the electron transfer between NADP(H and ferredoxins or flavodoxins. The inclusion of a plastidic FNR in Leptospira metabolism and in its parasitic life cycle is not currently understood. Bioinformatic analyses of the available genomic and proteins sequences showed that the presence of this enzyme in nonphotosynthetic bacteria is restricted to the Leptospira genus and that a [4Fe-4S] ferredoxin (LB107 encoded by the Leptospira genome may be the natural substrate of the enzyme. Leptospira FNR (LepFNR displayed high diaphorase activity using artificial acceptors and functioned as a ferric reductase. LepFNR displayed cytochrome c reductase activity with the Leptospira LB107 ferredoxin with an optimum at pH 6.5. Structural stability analysis demonstrates that LepFNR is one of the most stable FNRs analyzed to date. The persistence of a native folded LepFNR structure was detected in up to 6 M urea, a condition in which the enzyme retains 38% activity. In silico analysis indicates that the high LepFNR stability might be due to robust interactions between the FAD and the NADP(+ domains of the protein. The limited bacterial distribution of plastidic class FNRs and the biochemical and structural properties of LepFNR emphasize the uniqueness of this enzyme in the Leptospira metabolism. Our studies show that in L. interrogans a plastidic-type FNR exchanges electrons with a bacterial-type ferredoxin, process which has not been previously observed in nature.

  10. A highly stable plastidic-type ferredoxin-NADP(H) reductase in the pathogenic bacterium Leptospira interrogans.

    Science.gov (United States)

    Catalano-Dupuy, Daniela L; Musumeci, Matías A; López-Rivero, Arleth; Ceccarelli, Eduardo A

    2011-01-01

    Leptospira interrogans is a bacterium that is capable of infecting animals and humans, and its infection causes leptospirosis with a range of symptoms from flu-like to severe illness and death. Despite being a bacteria, Leptospira interrogans contains a plastidic class ferredoxin-NADP(H) reductase (FNR) with high catalytic efficiency, at difference from the bacterial class FNRs. These flavoenzymes catalyze the electron transfer between NADP(H) and ferredoxins or flavodoxins. The inclusion of a plastidic FNR in Leptospira metabolism and in its parasitic life cycle is not currently understood. Bioinformatic analyses of the available genomic and proteins sequences showed that the presence of this enzyme in nonphotosynthetic bacteria is restricted to the Leptospira genus and that a [4Fe-4S] ferredoxin (LB107) encoded by the Leptospira genome may be the natural substrate of the enzyme. Leptospira FNR (LepFNR) displayed high diaphorase activity using artificial acceptors and functioned as a ferric reductase. LepFNR displayed cytochrome c reductase activity with the Leptospira LB107 ferredoxin with an optimum at pH 6.5. Structural stability analysis demonstrates that LepFNR is one of the most stable FNRs analyzed to date. The persistence of a native folded LepFNR structure was detected in up to 6 M urea, a condition in which the enzyme retains 38% activity. In silico analysis indicates that the high LepFNR stability might be due to robust interactions between the FAD and the NADP(+) domains of the protein. The limited bacterial distribution of plastidic class FNRs and the biochemical and structural properties of LepFNR emphasize the uniqueness of this enzyme in the Leptospira metabolism. Our studies show that in L. interrogans a plastidic-type FNR exchanges electrons with a bacterial-type ferredoxin, process which has not been previously observed in nature.

  11. Global transcriptomic response of Leptospira interrogans serovar Copenhageni upon exposure to serum

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    Lo Miranda

    2010-01-01

    Full Text Available Abstract Background Leptospirosis is a zoonosis of worldwide distribution caused by infection with pathogenic serovars of Leptospira spp. The most common species, L. interrogans, can survive in the environment for lengthy periods of time in between infection of mammalian hosts. Transmission of pathogenic Leptospira to humans mostly occurs through abraded skin or mucosal surfaces after direct or indirect contact with infected animals or contaminated soil or water. The spirochete then spreads hematogenously, resulting in multi-organ failure and death in severe cases. Previous DNA microarray studies have identified differentially expressed genes required for adaptation to temperature and osmolarity conditions inside the host compared to those of the environment. Results In order to identify genes involved in survival in the early spirochetemic phase of infection, we performed a transcriptional analysis of L. interrogans serovar Copenhageni upon exposure to serum in comparison with EMJH medium. One hundred and sixty-eight genes were found to be differentially expressed, of which 55 were up-regulated and 113 were down-regulated. Genes of known or predicted function accounted for 54.5 and 45.1% of up- and down-regulated genes, respectively. Most of the differentially expressed genes were predicted to be involved in transcriptional regulation, translational process, two-component signal transduction systems, cell or membrane biogenesis, and metabolic pathways. Conclusions Our study showed global transcriptional changes of pathogenic Leptospira upon exposure to serum, representing a specific host environmental cue present in the bloodstream. The presence of serum led to a distinct pattern of gene expression in comparison to those of previous single-stimulus microarray studies on the effect of temperature and osmolarity upshift. The results provide insights into the pathogenesis of leptospirosis during the early bacteremic phase of infection.

  12. Ecology of Leptospira interrogans in Norway rats (Rattus norvegicus in an inner-city neighborhood of Vancouver, Canada.

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    Chelsea G Himsworth

    Full Text Available BACKGROUND: Leptospira interrogans is a bacterial zoonosis with a worldwide distribution for which rats (Rattus spp. are the primary reservoir in urban settings. In order to assess, monitor, and mitigate the risk to humans, it is important to understand the ecology of this pathogen in rats. The objective of this study was to characterize the ecology of L. interrogans in Norway rats (Rattus norvegicus in an impoverished inner-city neighborhood of Vancouver, Canada. METHODOLOGY/PRINCIPAL FINDINGS: Trapping was performed in 43 city blocks, and one location within the adjacent port, over a 12 month period. Kidney samples were tested for the presence of L. interrogans using PCR and sequencing. A multivariable model was built to predict L. interrogans infection status in individual rats using season and morphometric data (e.g., weight, sex, maturity, condition, etc. as independent variables. Spatial analysis was undertaken to identify clusters of high and low L. interrogans prevalence. The prevalence of L. interrogans varied remarkably among blocks (0-66.7%, and spatial clusters of both high and low L. interrogans prevalence were identified. In the final cluster-controlled model, characteristics associated with L. interrogans-infection in rats included weight (OR = 1.14, 95% CI = 1.07-1.20, increased internal fat (OR = 2.12, 95% CI = 1.06-4.25, and number of bite wounds (OR = 1.20, 95% CI = 0.96-1.49. CONCLUSIONS/SIGNIFICANCE: Because L. interrogans prevalence varied with weight, body fat, and bite wounds, this study suggests that social structure and interactions among rats may influence transmission. The prevalence and distribution of L. interrogans in rats was also highly variable even over a short geographic distance. These factors should be considered in future risk management efforts.

  13. LipL32 Is a Subsurface Lipoprotein of Leptospira interrogans: presentation of new data and reevaluation of previous studies.

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    Marija Pinne

    Full Text Available The agents of leptospirosis, a zoonosis with worldwide distribution, are pathogenic spirochetes belonging to the genus Leptospira. The leptospiral life cycle involves transmission via fresh water and colonization of the renal tubules of their reservoir hosts. Infection of accidental hosts, including humans, may result in life-threatening sequelae. Bacterial outer membrane proteins (OMPs, particularly those with surface-exposed regions, play crucial roles in pathogen virulence mechanisms and adaptation to environmental conditions, including those found in the mammalian host. Therefore, elucidation and characterization of the surface-exposed OMPs of Leptospira spp. is of great interest in the leptospirosis field. A thorough, multi-pronged approach for assessing surface exposure of leptospiral OMPs is essential. Herein, we present evidence for a sub-surface location for most or all of the major leptospiral lipoprotein, LipL32, based on surface immunofluorescence utilizing three different types of antibodies and four different permeabilization methods, as well as surface proteolysis of intact and lysed leptospires. We reevaluate prior evidence presented in support of LipL32 surface-exposure and present a novel perspective on a protein whose location has been misleading researchers, due in large part to its extraordinary abundance in leptospiral cells.

  14. Leptospira Interrogans induces fibrosis in the mouse kidney through Inos-dependent, TLR- and NLR-independent signaling pathways.

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    Martine Fanton d'Andon

    Full Text Available BACKGROUND: Leptospira (L. interrogans are bacteria responsible for a worldwide reemerging zoonosis. Rodents carry L. interrogans asymptomatically in their kidneys and excrete bacteria in the urine, contaminating the environment. Humans get infected through skin contact and develop a mild or severe leptospirosis that may lead to renal failure and fibrosis. L. interrogans provoke an interstitial nephritis, but the induction of fibrosis caused by L. interrogans has not been studied in murine models. Innate immune receptors from the TLR and NLR families have recently been shown to play a role in the development and progression of tissue fibrosis in the lung, liver and kidneys under different pathophysiological situations. We recently showed that TLR2, TLR4, and NLRP3 receptors were crucial in the defense against leptospirosis. Moreover, infection of a human cell line with L. interrogans was shown to induce TLR2-dependent production of fibronectin, a component of the extracellular matrix. Therefore, we thought to assess the presence of renal fibrosis in L. interrogans infected mice and to analyze the contribution of some innate immune pathways in this process. METHODOLOGY/PRINCIPAL FINDINGS: Here, we characterized by immunohistochemical studies and quantitative real-time PCR, a model of Leptospira-infected C57BL/6J mice, with chronic carriage of L. interrogans inducing mild renal fibrosis. Using various strains of transgenic mice, we determined that the renal infiltrates of T cells and, unexpectedly, TLR and NLR receptors, are not required to generate Leptospira-induced renal fibrosis. We also show that the iNOS enzyme, known to play a role in Leptospira-induced interstitial nephritis, also plays a role in the induction of renal fibrosis. CONCLUSION/SIGNIFICANCE: To our knowledge, this work provides the first experimental murine model of sustained renal fibrosis induced by a chronic bacterial infection that may be peculiar, since it does not rely on

  15. Prokaryotic expression of Leptospira interrogans FliH/Ⅰ/Y/N genes and determination of the protein locations in leptospiral envelope%问号钩端螺旋体鞭毛蛋白相关蛋白FliH/Ⅰ/Y/N基因原核表达和膜定位

    Institute of Scientific and Technical Information of China (English)

    徐韩飞; 阮萍; 廖苏梅; 杨平; 毛亚飞; 李立伟; 严杰

    2008-01-01

    目的 克隆问号钩端螺旋体(简称钩体)鞭毛相关蛋白编码jliH、fliⅠfliH、和fliN并构建其原核表达系统,制备表达产物抗血清并了解其蛋白的定位.方法 以苯酚-氯仿法提取的问号钩体黄疸出血群赖型赖株基凶组DNA为模板,用PCR扩增全长fliH,fliⅠ,firY和flfliN基因片段,T-A克隆后测序,继而构建上述目的 基因克隆的原核表达系统.采用SDS-PAGE和BioRad凝胶图像分析系统检查重组蛋白rFliH、rFliI、rFliY和rHiN的表达情况,Ni-NTA亲和层析法提纯目的 表达产物.皮下免疫家兔获得4种目的 重组蛋白抗血清,用ELISA和Western blot分别检测抗血清效价并了解抗血清与相应抗原结合的能力.采用免疫电镜技术对FliH、FliⅠ、FliY和FliN进行定位.结果 PCR扩增获得大小分别为924、1365、1065和318 bp的全长fliH,fliⅠ,fliY和fliN基因片段,与报道的序列比较.其核苷酸和氨基酸序列相似性均为100%.所构建的原核表达系统均能有效地表达目的 重组蛋白,其产量均约为20%.rFliH、rFliⅠ、rFliY和rHiN蛋白免疫家兔后能产生抗体,其兔抗血清ELISA效价达到1:100 000以上,并分别识别钩体相应重组蛋白和膜蛋白提取物而出现明显的Westem杂交条带.FiH、FliⅠ、FliY和FliN蛋白分布于问号钩体内膜、外膜或内外膜之间.结论 本研究成功地构建了能高效表达问号钩体鞭毛相关蛋白FliH、FliⅠ、FIiY和HiN的原核表达系统,并获得了能有效识别上述蛋白抗原的高效价抗血清.鞭毛相关蛋白HiH、Flil、FliY和FIiN是问号钩体内膜或外膜蛋白成分.%Objective To clone fliH, fliⅠ, fliY and fliN genes that encoding flagellum-associated proteins of L. interrogans for construction of their prokaryotic expression systems, and to determine the loca- tions of Flirt, FliⅠ, FIiY and FIiN. Methods The fliH, fliⅠ, fliY andfliN genes were amplified by PCR and sequenced after T-A cloning. Prokaryotie

  16. Leptospira interrogans serovar hardjo vaccination of pregnant beef cows and subsequent growth rate of progeny.

    Science.gov (United States)

    Holroyd, R G

    1980-10-01

    Five experiments with Leptospira interrogans serovar hardjo vaccine were carried out over a 6-year period in pregnant Brahman-cross and Sahiwal-cross cows in the dry tropics on northern Queensland. The numbers ranged from 127 breeders aged 2 to 5 years in 1972 to 344 breeders aged 2 to 9 years in 1977. Half of the cows were vaccinated twice in mid-pregnancy except for 1977, when they were vaccinated once. In 1975-1977 inclusive, half of the heifers were given an additional dose of vaccine at commencement of mating. Vaccination caused a significant (P less than 0.01) reduction of prenatal loss but not of perinatal or postnatal losses. Growth rates of calves from vaccinated and unvaccinated dams were similar.

  17. Experimental infection of calves and sheep with Leptospira interrogans serovar balcanica.

    Science.gov (United States)

    Durfee, P T; Presidente, P J

    1979-10-01

    Two of four calves inoculated with Leptospira interrogans serovar balcanica developed low microscopic agglutinating (MA) titres to serovar hardjo. A third calf had an MA titre of 1:1024 by day 19 post-inoculation (PI). Transient leptospiruria was recorded in one calf on days 12 and 13 PI. An in-contact calf did not seroconvert. None of the calves had fever or other clinical signs of disease. Four ewes inoculated with balcanica developed MA titres to hardjo by day 13 PI, and a transient leptospiruria between days 14 and 25 PI. None of the ewes showed any evidence of clinical disease and three of them delivered healthy lambs 22 to 64 days PI. One ewe had mild lesions of focal interstitial nephritis.

  18. Expression and Comparative Analysis of Genes Encoding Outer Membrane Proteins LipL21, LipL32 and OmpL1 in Epidemic Leptospires

    Institute of Scientific and Technical Information of China (English)

    Xiang-Yan ZHANG; Xiao-Kui GUO; Yang YU; Ping HE; Yi-Xuan ZHANG; Bao-Yu HU; Yang YANG; Yi-Xin NIE; Xiu-Gao JIANG; Guo-Ping ZHAO

    2005-01-01

    Leptospiral outer membrane proteins (OMPs) are highly conserved in different species, and play an essential role in the development of new immunoprotection and serodiagnosis strategies. The genes encoding LipL21, LipL32 and OmpL1 were cloned from the complete genome sequence of Leptospira interrogans serovar lai strain Lai and expressed in vitro. Sequence comparison analysis revealed that the three genes were highly conserved among distinct epidemic leptospires, including three major epidemic species Leptospira interrogans, Leptospira borgpetersenii and Leptospira weilii, in China. Immunoblot analysis was further performed to scrutinize 15 epidemic Leptospira reference strains using the antisera of the recombinant OMPs. Both immunoblot assay and reverse transcription-polymerase chain reaction demonstrated that these three OMPs were conservatively expressed in pathogenic L. interrogans strains and other pathogenic leptospires.Additionally, the use of these recombinant OMPs as antigens in enzyme-linked immunosorbent assay (ELISA)for serodiagnosis of leptospirosis was evaluated. The recombinant LipL32 and OmpL1 proteins showed a high degree of ELISA reactivity with sera from patients infected with L. interrogans strain Lai and other pathogenic leptospires. These results may contribute to the identification of candidates for broad-range vaccines and immunodiagnostic antigens in further research.

  19. Characterization of a bifunctional enzyme with (p)ppGpp-hydrolase/synthase activity in Leptospira interrogans.

    Science.gov (United States)

    He, Ping; Deng, Cong; Liu, Boyu; Zeng, LingBing; Zhao, Wei; Zhang, Yan; Jiang, XuCheng; Guo, XiaoKui; Qin, JinHong

    2013-11-01

    Alarmone Guanosine 5'-diphosphate (or 5'-triphosphate) 3'-diphosphate [(p)ppGpp] is the key component that globally regulates stringent control in bacteria. There are two homologous enzymes, RelA and SpoT in Escherichia coli, which are responsible for fluctuations in (p)ppGpp concentration inside the cell, whereas there exists only a single RelA/SpoT enzyme in Gram-positive bacteria. We have identified a bifunctional enzyme with (p)ppGpp-hydrolase/synthase activity in Leptospira interrogans. We show that the relLin gene (LA_3085) encodes a protein that fully complements the relA/spoT double mutants in E. coli. The protein functions as a (p)ppGpp degradase as well as a (p)ppGpp synthase when the cells encounter amino acid stress and deprivation of carbon sources. N-terminus HD and RSD domains of relLin (relLinN ) were observed to restore growth of double mutants of E. coli. Finally, We demonstrate that purified RelLin and RelLinN show high (p)ppGpp synthesis activity in vitro. Taken together, our results suggest that L. interrogans contain a single Rel-like bifunctional protein, RelLin , which plays an important role in maintaining the basal level of (p)ppGpp in the cell potentially contributing to the regulation of bacterial stress response.

  20. Whole-Genome Sequence of Leptospira interrogans Serovar Hardjo Subtype Hardjoprajitno Strain Norma, Isolated from Cattle in a Leptospirosis Outbreak in Brazil.

    Science.gov (United States)

    Cosate, M R V; Soares, S C; Mendes, T A; Raittz, R T; Moreira, E C; Leite, R; Fernandes, G R; Haddad, J P A; Ortega, J Miguel

    2015-11-05

    Leptospirosis is caused by pathogenic bacteria of the genus Leptospira spp. This neglected re-emergent disease has global distribution and relevance in veterinary production. Here, we report the whole-genome sequence and annotation of Leptospira interrogans serovar Hardjo subtype Hardjoprajitno strain Norma, isolated from cattle in a livestock leptospirosis outbreak in Brazil.

  1. First isolation of leptospires from dairy goats in Brazil Primeiro isolamento de leptospiras em caprinos no Brasil

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    Walter Lilenbaum

    2007-09-01

    Full Text Available Leptospires have never been recovered from goats in Brazil. Serum samples were obtained from 248 goats from Rio de Janeiro and from the seroreactive animals, urine samples were collected and processed for Leptospira isolation. A total of 52 positive reactions were observed, corresponding to 20.9% of the samples. The most prevalent reactions were to serovars Hardjo (36.5%, Shermani (30.8%, Icterohaemorrhagiae (9.6%, Grippotyphosa (9.6%, Autumnalis (5.8%, Castellonis (3.8% and Bratislava (3.8%. Two strains of Leptospira sp. were isolated, both in the same region, but from different flocks. Presumptive identification based on serologic methods suggests those strains to be from Grippotyphosa serogroup.Leptospiras nunca foram isolados de caprinos no Brasil. Amostras de soros foram obtidas de 248 caprinos no Rio de Janeiro, e, dos animais sororeativos, amostras de urina foram coletadas e processadas para isolamento de leptospiras. Um total de 52 (20,9% reações positivas foi observado. Os serovares mais prevalentes foram Hardjo (36,5%, Shermani (30,8%, Icterohaemorrhagiae (9,6%, Grippotyphosa (9,6%, Autumnalis (5,8%, Castellonis (3,8% e Bratislava (3,8%. Duas estirpes de Leptospira sp. foram isoladas, ambas na mesma região, mas de diferentes rebanhos. A identificação sorológica presuntiva sugere trataram-se de amostras do sorogrupo Grippotyphosa.

  2. Dual nuclease activity of a Cas2 protein in CRISPR-Cas subtype I-B of Leptospira interrogans.

    Science.gov (United States)

    Dixit, Bhuvan; Ghosh, Karukriti Kaushik; Fernandes, Gary; Kumar, Pankaj; Gogoi, Prerana; Kumar, Manish

    2016-04-01

    Leptospira interrogans serovar Copenhageni strain Fiocruz L1-130 carries a set of cas genes associated with CRISPR-Cas subtype I-B. Herein, we report for the first time active transcription of a set of cas genes (cas1 to cas8) of L. interrogans where cas4, cas1, cas2 and cas6, cas3, cas8, cas7, cas5 are clustered together in two independent operons. As an initial step toward comprehensive understanding of CRISPR-Cas system in spirochete, the biochemical study of one of the core Leptospira Cas2 proteins (Lep_Cas2) showed nuclease activity on both DNA and RNA in a nonspecific manner. Additionally, unlike other known Cas2 proteins, Lep_Cas2 showed metal-independent RNase activity and preferential activity on RNA over DNA. These results provide insight for understanding Cas2 diversity existing in the prokaryotic adaptive immune system.

  3. Three case studies involving Leptospira interrogans serovar pomona infection in mixed farming units.

    Science.gov (United States)

    Gummow, B; Myburgh, J G; Thompson, P N; van der Lugt, J J; Spencer, B T

    1999-03-01

    Three case studies involving Leptospira interrogans serovar pomona outbreaks within mixed farming systems in South Africa are described. On 2 farms, pigs constituted the main enterprise with cattle and sheep of secondary importance. On each of these 2 farms, abortion due to L. pomona in sows was confirmed by culture, and antibody titres to pomona were detected in cattle, sheep, horses and dogs. On the 3rd farm, a piggery was of secondary importance to cattle farming. Abortion and death in cows occurred on this farm and serology showed titres to various serovars, including pomona. L. pomona was also isolated from bovine urine, an aborted bovine foetus and kidneys from slaughtered pigs. This particular case study was regarded as clinically atypical in that adult Jersey cattle died of acute leptospirosis in a semiarid region of South Africa. In all 3 case studies, the poor management of pig effluent and of the drinking water and its sources played a pivotal role in the transmission of the disease. Inadequate vaccination of animals against Leptospira and poor record-keeping within the secondary farming enterprises were also contributing factors to the spread of leptospirosis.

  4. Three case studies involving Leptospira interrogans serovar pomona infection in mixed farming units : case report

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    B. Gummow

    1999-07-01

    Full Text Available Three case studies involving Leptospira interrogans serovar pomona outbreaks within mixed farming systems in South Africa are described. On 2 farms, pigs constituted the main enterprise with cattle and sheep of secondary importance. On each of these 2 farms, abortion due to L. pomona in sows was confirmed by culture, and antibody titres to pomona were detected in cattle, sheep, horses and dogs. On the 3rd farm, a piggery was ofsecondary importance to cattle farming. Abortion and death in cows occurred on this farmand serology showed titres to various serovars, including pomona. L. pomona was also isolated from bovine urine, an aborted bovine foetus and kidneys from slaughtered pigs. This particular case study was regarded as clinically atypical in that adult Jersey cattle died of acute leptospirosis in a semiarid region of South Africa. In all 3 case studies, the poor management of pig effluent and of the drinking water and its sources played a pivotal role in the transmission of the disease. Inadequate vaccination of animals against Leptospira and poor record-keeping within the secondary farming enterprises were also contributing factors to the spread of leptospirosis.

  5. Proteína LIC10494 de Leptospira interrogans serovar Copenhageni: modelo estructural y regiones funcionales asociadas

    OpenAIRE

    Orlando Emilio Acevedo; George Emílio Barreto; Janneth González-Santos

    2012-01-01

    Protein LIC10494 of Leptospira interrogans serovar Copenhageni: structural model and associated functional regions. Objective.Predict by computational means the 3D structure of the antigenic protein LIC10494 and report associated important functional regionsfor its pathogenicity and immunogenicity. Materials and methods. We performed a computational analysis of the primary structure ofLIC10494 using the servers BLAST, PROTPARAM, PROTSCALE, DAS, SOSUI, TOPPRED, TMAP, TMpred, SPLIT4, PHDHTM,TMH...

  6. Identification and classification of all potential hemolysin encoding genes and their products from Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai

    Institute of Scientific and Technical Information of China (English)

    Yi-xuan ZHANG; Yan GENG; Bo BI; Jian-yong HE; Chun-fu WU; Xiao-kui GUO; Guo-ping ZHAO

    2005-01-01

    Aim: To identify and classify all potential hemolysin candidates of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai. Methods: All of thepotential hemolysin encoding genes were characterized in silico. These genes were cloned and expressed in Escherichia coli. The hemolytic activities of the expressed proteins were assayed observing the hemolysis on sheep blood agar plates. Sphingomyelinase activities of the hemolysin candidates were measured by thin-layer chromatography (TLC) and HPLC for sphingomyelin-hydrolysis. Expression and secretion of the hemolysins in L interrogans were studied by reverse transcription polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assays. Results and Conclusion: The hemolytic activities of hemolysin candidates (LA0327, LA0378, LA1027, LA1029, LA1650, LA3050,LA3937, LA4004) from L interrogans strain Lai were confirmed. They were further divided into two groups, sphingomyelinase hemolysins and non-sphingomyelinase hemolysins, based on their ability to hydrolyze sphingomyelin. Most of these hemolysins were actually expressed in living L interrogans and some of them were secreted into the environment. This study establishes an essential and complete basis for further studying the contribution of hemolysins to the pathogenesis of L interrogans.

  7. Seroprevalence and risk factors associated with within-flock transmission of Leptospira interrogans in transhumant farming systems in Mexico.

    Science.gov (United States)

    Arteaga-Troncoso, G; Jiménez-Estrada, J M; Montes De Oca-Jimenez, R; López-Hurtado, M; Luna-Alvarez, M; Hernandez-Andrade, L; Moreno-Alfaro, A; Galan-Herrera, J F; Guerra-Infante, F M

    2015-10-01

    A number of recent reports emphasize the risk of zoonotic diseases and the high degree of prevalence of asymptomatic animals infected with Leptospira interrogans. This report sought to assess the prevalence of antibodies to certain serovars of L. interrogans, and to describe the association between seropositivity and risk factors associated with within-flock transmission in a mountainous region of Mexico. Overall seroprevalence to L. interrogans was 54·5% (95% confidence interval 48·3-60·7); the most frequent serovar was Icterohaemorrhagiae. The accumulation of placentas and fetuses at a site close to lambing paddocks can play a significant role as a risk factor for within-flock transmission of L. interrogans in transhumant farming systems in the municipality of Xalatlaco. The high prevalence of L. interrogans antibodies supports the hypothesis that natural foci of this zoonosis are present in sheep flocks in this area. These findings emphasize the need for planning and implementation of control programmes for ovine leptospirosis in Mexico and elsewhere.

  8. Detection of leptospires from infected urine and tissue samples in vitro by modified Fontana silver stain Detecção de leptospiras na urina e nos tecidos infectados in vitro por impregnação com prata Fontana modificada

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    Islay Rodríguez

    2013-02-01

    Full Text Available INTRODUCTION: The microbiological diagnosis of leptospirosis comprises bacteriological and serological methods. The former ones allow the direct detection of leptospires and are considered presumptive with the exception of culture. Therefore, they constitute invaluable tools for rapid diagnosis, mainly in samples from deceased subjects. OBJECTIVE: To evaluate a modified Fontana silver staining method in experimentally infected samples. MATERIAL AND METHODS: Human and animal (hamster urine samples were experimentally infected with different strains of Leptospira interrogans sensu lato. Liquid culture medium, leptospira cultures, experimentally infected and non-infected human urine samples, clarified and non-clarified imprints, and clarified and non-clarified suspension smears from tissues of experimentally infected and non-infected hamsters were applied for the ass essment of silver staining. The analytical sensitivity of the assay was compared with dark field microscopy and culture. Other bacterial and fungi species were also used. RESULTS: The modified Fontana silver staining allowed the accurate observation of the well-defined leptospire helical structure. On leptospire cultures from infected human samples, we could observe until (1-10 × 10³ leptospires/ml, higher sensitivity in comparison with direct dark field microscopy and lower in comparison with culture. The best results in tissues were obtained on clarified imprints and non-clarified suspension smears. Morphological and stainable structures compatible with leptospires were not observed in the samples without them. CONCLUSION: This procedure allowed differentiating the characteristic morphology of leptospires. As its application suggests, it consists of a simple and easily conducted procedure with stable reagents.INTRODUÇÃO: O diagnóstico microbiológico da leptospirose inclui métodos bacteriológicos e sorológicos; os primeiros permitem a detecção direta de leptospiras e,

  9. Prevalence of antibodies against Borrelia burgdorferi, Anaplasma phagocytophilum, and Leptospira interrogans serovars in Bernese Mountain Dogs.

    Science.gov (United States)

    Preyß-Jägeler, C; Müller, E; Straubinger, R K; Hartmann, K

    2016-01-01

    Bernese Mountain Dogs (BMD) have a higher prevalence of Borrelia burgdorferi sensu lato (Bbsl) antibodies than other breeds, but it is not known whether this is the case for other pathogens. Therefore, the aim of the study was to determine the frequency and level of specific antibodies against members of the Bbsl group, Anaplasma phagocytophilum (Ap), and Leptospira (L.) interrogans serovars in BMD and compare the results with those found in dogs of other breeds. A total of 171 healthy BMD and 57 healthy control dogs of other breeds were included in the study. Controls were large dogs (> 30 kg) with long, dark hair coats. A two-tiered testing method consisting of computerized kinetic enzyme-linked immunosorbent assay (KELA) and Western blotting was used for detection of antibodies against Bbsl, an immunofluorescence assay (IFA) was used for detection of antibodies against Ap, and microscopic agglutination test (MAT) for antibodies to 18 different serovars of L. interrogans. The prevalence of anti-Bbsl antibodies was significantly higher in BMD (43.3%) than in controls (17.5%) (p < 0.001). Antibodies to Bbsl attributable to vaccination were excluded from the calculation of prevalence. Antibodies to Ap were found in 50.3% of BMD, whereas only 24.6% of the controls dogs were tested positive for Ap (p < 0.001). Antibody titers of the 18 different serovars of L. interrogans antibodies did not differ significantly between BMD and control dogs except for L. copenhageni antibody titers which were higher in BMD. Significantly higher antibody titers to L. canicola (p = 0.003), L. copenhageni (p = 0.005), L. grippothyphosa (p = 0.029) and L. vanderhoedoni (p = 0.035) were seen in BMD compared to control dogs. BMD had a higher prevalence of anti-Bbsl, anti-L. copenhageni and anti-Ap antibodies than control dogs. Significantly higher antibody titers against L. canicola (p = 0.003), L. copenhageni (p = 0.005), L. grippothyphosa (p = 0.029) and L

  10. First Isolates of Leptospira spp., from Rodents Captured in Angola

    Science.gov (United States)

    Fortes-Gabriel, Elsa; Carreira, Teresa; Vieira, Maria Luísa

    2016-01-01

    Rodents play an important role in the transmission of pathogenic Leptospira spp. However, in Angola, neither the natural reservoirs of these spirochetes nor leptospirosis diagnosis has been considered. Regarding this gap, we captured rodents in Luanda and Huambo provinces to identify circulating Leptospira spp. Rodent kidney tissue was cultured and DNA amplified and sequenced. Culture isolates were evaluated for pathogenic status and typing with rabbit antisera; polymerase chain reaction (PCR) and sequencing were also performed. A total of 37 rodents were captured: Rattus rattus (15, 40.5%), Rattus norvegicus (9, 24.3%), and Mus musculus (13, 35.2%). Leptospiral DNA was amplified in eight (21.6%) kidney samples. From the cultures, we obtained four (10.8%) Leptospira isolates belonging to the Icterohaemorrhagiae and Ballum serogroups of Leptospira interrogans and Leptospira borgpetersenii genospecies, respectively. This study provides information about circulating leptospires spread by rats and mice in Angola. PMID:26928840

  11. Protection of Guinea Pigs against Leptospira interrogans Serovar Lai by LipL21 DNA Vaccine

    Institute of Scientific and Technical Information of China (English)

    Hanjiang He; Wenyu Wang; Zhongdao Wu; Zhiyue Lv; Jun Li; Lizhi Tan

    2008-01-01

    In this study,the full lipL21 gene fragment encoding outer membrane protein LipL21 was cloned from L. Interrogans serovar Lai and inserted into eukaryotic expression vector pcDNA3.1(+).The guinea pigs were immunized with pcDNA3.1(+)-lipL21,pcDNA3.1(+) or PBS.Six weeks after the second immunization,the splenocytes were isolated to detect their proliferative ability by lymphocyte transformation experiments.In addition,microscopic agglutination test was used for quantitative detection of specific antibodies.The rest guinea pigs were challenged intraperitoneally with L.interogans sorevar Lai.Then,protective effect was evaluated on the basis of survival and histopathological lesions in the kidneys,lungs,and liver.The lipL21 gene Was successfully expressed in COS-7 cells through recombinant pcDNA3.1(+)-lipL21.The titer of specific antibodies substantially increased,and the stimulation index of splenocytes increased significantly.Hence,the pcDNA3.1(+)-lipL21 could protect the immunized guinea pigs from homotypic Leptospira infection.Furthermore,no obvious pathologic changes were observed in the pcDNA3.1(+)-lipL21 immunized guinea pigs.The results showed that the protective effect with pathogenic strains of Leptospira was shared by LipL21 mediated through a plasmid vector. Consequently,these results indicated that the lipL21 DNA vaccine Was a promising candidate for the prevention of leptospirosis.

  12. Management practices as risk factors for the presence of bulk milk antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in Irish dairy herds.

    Science.gov (United States)

    O' Doherty, E; Berry, D P; O' Grady, L; Sayers, R

    2014-06-01

    A survey of management practices in 309 Irish dairy herds was used to identify risk factors for the presence of antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in extensively managed unvaccinated dairy herds. A previous study documented a herd-level seroprevalence in bulk milk of 49%, 19% and 86% for Salmonella, Neospora caninum and leptospira interrogans serovar hardjo, respectively in the unvaccinated proportion of these 309 herds in 2009. Association analyses in the present study were carried out using multiple logistic regression models. Herds where cattle were purchased or introduced had a greater likelihood of being positive to leptospira interrogans serovar hardjo (PNeospora caninum (PNeospora caninum possibly due to limited access of dogs to infected materials including afterbirths. The information from this study will assist in the design of suitable control programmes for the diseases under investigation in pasture-based livestock systems.

  13. Leptospira interrogans serovar canicola: a causal agent of sow abortions in Arequipa, Peru.

    Science.gov (United States)

    Paz-Soldán, S V; Dianderas, M T; Windsor, R S

    1991-11-01

    An outbreak of abortions, stillbirths, mummified piglets and neonatal deaths in a pig herd in Arequipa, Peru is described. A total of 31 of 240 sows aborted between May and September 1988. When sera were examined 12 of 14 had very high titres of antibody to canicola PC125 and canicola Hond Utrecht, but there were also high titres of antibody to other leptospiral serovars. A detailed investigation was made and serovar canicola PC125 was isolated from the urine of four sows which had aborted and the kidney of one slaughter pig. Antibodies to various serovars of Leptospira were demonstrated in 11 of 17 sows which had aborted, two of six sows which had normal litters, nine of 18 boars, four of 39 slaughter pigs and four of 14 workers on the farm. The outbreak was brought under control by treatment and vaccination coupled with a thorough cleaning of the farm and control of the wild animal population. It is suggested that the infection was brought onto the farm by wild animals and that the disease is more common in Arequipa than was previously supposed.

  14. Characterization of a novel toxin-antitoxin module, VapBC, encoded by Leptospira interrogans chromosome

    Institute of Scientific and Technical Information of China (English)

    Yi Xuan ZHANG; Xiao Kui GUO; Chuan WU; Bo BI; Shuang Xi REN; Chun Fu WU; Guo Ping ZHAO

    2004-01-01

    Comparative genomic analysis of the coding sequences (CDSs) of Leptospira interrogans revealed a pair of closely linked genes homologous to the vapBC loci of many other bacteria with respect to both deduced amino acid sequences and operon organizations. Expression of single vapC gene in Escherichia coli resulted in inhibition of bacterial growth,whereas co-expression of vapBC restored the growth effectively. This phenotype is typical for three other characterized toxin-antitoxin systems of bacteria, i.e., mazEF[1], relBE[2] and chpIK[3]. The VapC proteins of bacteria and a thermophilic archeae, Solfolobus tokodaii, form a structurally distinguished group of toxin different from the other known toxins of bacteria. Phylogenetic analysis of both toxins and antitoxins of all categories indicated that although toxins were evolved from divergent sources and may or may not follow their speciation paths (as indicated by their 16s RNA sequences), co-evolution with their antitoxins was obvious.

  15. Crystal structures of Leptospira interrogans FAD-containing ferredoxin-NADP+ reductase and its complex with NADP+.

    Science.gov (United States)

    Nascimento, Alessandro S; Catalano-Dupuy, Daniela L; Bernardes, Amanda; Neto, Mario de Oliveira; Santos, Maria Auxiliadora M; Ceccarelli, Eduardo A; Polikarpov, Igor

    2007-10-24

    Ferredoxin-NADP(H) reductases (FNRs) are flavoenzymes that catalyze the electron transfer between NADP(H) and the proteins ferredoxin or flavodoxin. A number of structural features distinguish plant and bacterial FNRs, one of which is the mode of the cofactor FAD binding. Leptospira interrogans is a spirochaete parasitic bacterium capable of infecting humans and mammals in general. Leptospira interrogans FNR (LepFNR) displays low sequence identity with plant (34% with Zea mays) and bacterial (31% with Escherichia coli) FNRs. However, LepFNR contains all consensus sequences that define the plastidic class FNRs. The crystal structures of the FAD-containing LepFNR and the complex of the enzyme with NADP+, were solved and compared to known FNRs. The comparison reveals significant structural similarities of the enzyme with the plastidic type FNRs and differences with the bacterial enzymes. Our small angle X-ray scattering experiments show that LepFNR is a monomeric enzyme. Moreover, our biochemical data demonstrate that the LepFNR has an enzymatic activity similar to those reported for the plastidic enzymes and that is significantly different from bacterial flavoenzymes, which display lower turnover rates. LepFNR is the first plastidic type FNR found in bacteria and, despite of its low sequence similarity with plastidic FNRs still displays high catalytic turnover rates. The typical structural and biochemical characteristics of plant FNRs unveiled for LepFNR support a notion of a putative lateral gene transfer which presumably offers Leptospira interrogans evolutionary advantages. The wealth of structural information about LepFNR provides a molecular basis for advanced drugs developments against leptospirosis.

  16. Crystal structures of Leptospira interrogans FAD-containing ferredoxin-NADP+ reductase and its complex with NADP+

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    Ceccarelli Eduardo A

    2007-10-01

    Full Text Available Abstract Background Ferredoxin-NADP(H reductases (FNRs are flavoenzymes that catalyze the electron transfer between NADP(H and the proteins ferredoxin or flavodoxin. A number of structural features distinguish plant and bacterial FNRs, one of which is the mode of the cofactor FAD binding. Leptospira interrogans is a spirochaete parasitic bacterium capable of infecting humans and mammals in general. Leptospira interrogans FNR (LepFNR displays low sequence identity with plant (34% with Zea mays and bacterial (31% with Escherichia coli FNRs. However, LepFNR contains all consensus sequences that define the plastidic class FNRs. Results The crystal structures of the FAD-containing LepFNR and the complex of the enzyme with NADP+, were solved and compared to known FNRs. The comparison reveals significant structural similarities of the enzyme with the plastidic type FNRs and differences with the bacterial enzymes. Our small angle X-ray scattering experiments show that LepFNR is a monomeric enzyme. Moreover, our biochemical data demonstrate that the LepFNR has an enzymatic activity similar to those reported for the plastidic enzymes and that is significantly different from bacterial flavoenzymes, which display lower turnover rates. Conclusion LepFNR is the first plastidic type FNR found in bacteria and, despite of its low sequence similarity with plastidic FNRs still displays high catalytic turnover rates. The typical structural and biochemical characteristics of plant FNRs unveiled for LepFNR support a notion of a putative lateral gene transfer which presumably offers Leptospira interrogans evolutionary advantages. The wealth of structural information about LepFNR provides a molecular basis for advanced drugs developments against leptospirosis.

  17. Protección inducida por nanococleatos derivados de proteoliposomas de Leptospira interrogans serovar Canicola

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    Beatriz Tamargo

    2012-04-01

    Full Text Available Desde los años 20 del pasado siglo, hasta el presente, en el mundo se han desarrollado y empleado vacunas de células enteras contra la leptospirosis que confieren una corta inmunidad; la mayoría no adyuvadas y dirigidas, fundamentalmente, contra los diferentes serogrupos de la especie Leptospira interrogans, contenidos en las preparaciones. Numerosos han sido los intentos realizados para lograr una formulación vacunal más pura, efectiva, de amplio espectro y duración de la protección que las bacterinas de células enteras inactivadas. Sin embargo, hasta el momento no se ha registrado ninguna vacuna con tales características. En el presente trabajo se obtuvieron antígenos de membrana externa a partir de una cepa cubana autóctona (Cepa 87, L. interrogans serovar Canicola, mediante una modificación de la tecnología para la producción de vesículas de membrana, patentada por investigadores del Instituto Finlay. Estos antígenos con estructura nanoproteoliposómica fueron formulados/adyuvados mediante diferentes estrategias, logrando cinco preparaciones con estructura coclear, que constituyen nanopartículas de aproximadamente 100 a 150 nm de largo y entre 15 a 30 nm de diámetro. Los inmunógenos se inocularon en el biomodelo Mesocrisetus aureatus, con dos dosis e intervalo de seis semanas. El reto fue realizado con 100.000 DL 50 . Los resultados demuestran que las nuevas formulaciones vacunales confieren protección frente al reto homólogo y fueron capaces de eliminar el estado de portador, lo que unido a la robustez del método de preparación, el mayor nivel de pureza, en comparación con las bacterinas, y la no necesidad del hidróxido de aluminio, las convierten en una alternativa de interés para continuar su desarrollo.

  18. Detection of leptospiral antibodies by microscopic agglutination test in north-east of Iran

    Institute of Scientific and Technical Information of China (English)

    Ehsanollah Sakhaee; Gholam Reza Abdollah pour

    2011-01-01

    Objective: To detect leptospiral antibodies by microscopic agglutination test (MAT) in north-east of Iran. Methods: This study was conducted to evaluate prevalence of human leptospiral infections by MAT, using six current reference strains of Leptospira interrogans in north-east of Iran. A total of 285 serum samples were collected from three north-east provinces of Iran, from December, 2009 to June, 2010. Results: Antibodies were detected at least against one serovar of Leptospira interrogans in 45 sera (15.79 %) among 285 samples at a dilution 1:100 or greater. Positive titers against more than one serovar were detected in 24 sera of the positive samples. Therefore, there were 75 positive reactions against different serovar of Leptospira interrogans. Positive titers were recorded against serovar icterohaemorrhagiae (31 samples), hardjo (26 samples), grippotyphosa (7 samples), pomona (5 samples), canicola (4 samples) and ballum (2 sample).Conclusions:In present study the most prevalent (Leptospira icterohaemorrhagiae) and the least prevalent (Leptospira ballum) serovar are different from previous studies. Maybe, species and prevalence of serovars change during the time in one area and between regions.

  19. [Demonstration of intraocular leptospira in 4 horses suffering from equine recurrent uveitis (ERU)].

    Science.gov (United States)

    Brem, S; Gerhards, H; Wollanke, B; Meyer, P; Kopp, H

    1998-01-01

    Vitreous samples from 43 horses which underwent vitrectomy because of equine recurrent uveitis (ERU) were cultured for leptospires. Out of 4 vitreous samples (4/43 = 9%), leptospires could be isolated. In 3 cases, serovar grippotyphosa, and in one case, a serovar out of the serogroup Australis were identified. So for the first time, in several horses with ERU in vivo cultures of vitreous material were positive for leptospires. A strong evidence of association between leptospiral infection and uveitis is discussed for many years. In this investigation the leptospiral etiology is confirmed. Vitreous material from 42 and serum samples from 40 horses were tested for specific antibodies to leptospira by microagglutination test (MAT). In 34 vitreous samples (34/42 = 81%), leptospiral antibody titers of 1:50 or higher were detected. In 33 horses (33/40 = 83%) leptospiral antibody titers of 1:50 or higher could also be detected in the serum. Altogether, leptospiral antibodies were detected by the MAT in the serum and in the vitreous material of 39 of 43 horses (= 91%) subjected to vitrectomy. These results indicate, that ERU is probably often a sequel to systemic Leptospira interrogans infection. The presence of intact leptospires and specific antibodies in eyes affected with ERU indicates a local antibody production to leptospira organisms and/or their antigens.

  20. Draft genome of the Leptospira interrogans strains, Acegua, RCA, Prea, and Capivara, obtained from wildlife maintenance hosts and infected domestic animals

    Science.gov (United States)

    Kremer, Frederico S; Eslabão, Marcus R; Jorge, Sérgio; Oliveira, Natasha R; Labonde, Julia; Santos, Monize NP; Monte, Leonardo G; Grassmann, André A; Cunha, Carlos EP; Forster, Karine M; Moreno, Luísa Z; Moreno, Andrea M; Campos, Vinicius F; McBride, Alan JA; Pinto, Luciano S; Dellagostin, Odir A

    2016-01-01

    In the present paper, we announce new draft genomes of four Leptospira interrogans strains named Acegua, RCA, Prea, and Capivara. These strains were isolated in the state of Rio Grande do Sul, Brazil, from cattle, dog, Brazilian guinea pig, and capybara, respectively. PMID:27074260

  1. Draft genome of the Leptospira interrogans strains, Acegua, RCA, Prea, and Capivara, obtained from wildlife maintenance hosts and infected domestic animals

    Directory of Open Access Journals (Sweden)

    Frederico S Kremer

    2016-04-01

    Full Text Available In the present paper, we announce new draft genomes of four Leptospira interrogans strains named Acegua, RCA, Prea, and Capivara. These strains were isolated in the state of Rio Grande do Sul, Brazil, from cattle, dog, Brazilian guinea pig, and capybara, respectively.

  2. Draft genome of the Leptospira interrogans strains, Acegua, RCA, Prea, and Capivara, obtained from wildlife maintenance hosts and infected domestic animals

    OpenAIRE

    Kremer,Frederico S; Eslabão,Marcus R; Sérgio Jorge; Oliveira, Natasha R; Julia Labonde; Monize NP Santos; Monte, Leonardo G.; André A Grassmann; Carlos EP Cunha; Karine M. Forster; Moreno, Luísa Z; Moreno,Andrea M.; Campos, Vinicius F; Alan JA McBride; Pinto, Luciano S.

    2016-01-01

    In the present paper, we announce new draft genomes of four Leptospira interrogans strains named Acegua, RCA, Prea, and Capivara. These strains were isolated in the state of Rio Grande do Sul, Brazil, from cattle, dog, Brazilian guinea pig, and capybara, respectively.

  3. Direct Detection and Differentiation of Pathogenic Leptospira Species Using a Multi-Gene Targeted Real Time PCR Approach

    OpenAIRE

    Ana Sofia Ferreira; Pedro Costa; Teresa Rocha; Ana Amaro; Maria Luísa Vieira; Ahmed Ahmed; Gertrude Thompson; Hartskeerl, Rudy A.; João Inácio

    2014-01-01

    Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpet...

  4. [Detection of leptospira by culture of vitreous humor and detection of antibodies against leptospira in vitreous humor and serum of 225 horses with equine recurrent uveitis].

    Science.gov (United States)

    Dorrego-Keiter, Elisa; Tóth, József; Dikker, Lieke; Sielhorst, Jutta; Schusser, Gerald Fritz

    2016-01-01

    In the ongoing discussion regarding the aetiopathogenesis of equine recurrent uveitis (ERU) it was the aim of the present study to elucidate the relationship of leptospira infection and ERU. In a population of 225 horses leptospira were examined in vitreous humor by culture and leptospira antibody were detected in vitreous humor and serum samples. Preoperative serum samples were collected from 221/225 ERU patients of different age, gender and breed. Undiluted vitreous humor was aseptically taken from 198/225 patients that underwent pars plana vitrectomy at the beginning of surgery and from 27/225 patients' eyeball after enucleation: Serum and vitreous humor were tested for specific leptospiral antibodies by microscopic agglutination test (MAT). Furthermore, vitreous humor was examined by culture. 20 patients which were euthanized due to a live-threatening disease other than ERU served as a control group. A total of 127/221 (57.5%) horses had serum antibodies (≥ 1:100). Most frequently antibodies against L. interrogans serovar Grippotyphosa were detected (79/127), followed by L. interrogans serovar lcterohaemorrhagiae (34/127) and L. interrogans serovar Bratislava (29/127). Only 79/225 horses (35.1%) had leptospiral antibodies in vitreous humor, in which L. interrogans serovar Grippotyphosa (67/79) was identified most frequently followed by L. interrogans serovar Pomona (18/79) and L. interrogans serovar lcterohaemorrhagiae (8/79) which was identified as single or multiple reaction. Isolation of leptospira from vitreous humor was positive in 34/212 horses (16%). 10/20 control horses had a positive antibody titer against leptospira in serum and 2/20 horses in vitreous humor, whereas there was no leptospira detected in culture. The result of 84% negative cultures from vitreous humor of 212 ERU patients is decisive for the diagnosis and therapy of ERU.

  5. Cytotoxic activities of Leptospira interrogans hemolysin SphH as a pore-forming protein on mammalian cells.

    Science.gov (United States)

    Lee, Seoung Hoon; Kim, Sangduk; Park, Seung Chul; Kim, Min Ja

    2002-01-01

    Leptospirosis is a spirochetal zoonosis that causes an acute febrile systemic illness in humans. Leptospira sp. hemolysins have been shown to be virulence factors for the pathogenesis of leptospirosis. Previously, we cloned a hemolysin SphH of Leptospira interrogans serovar lai, a homologue of L. borgpetersenii sphingomyelinase (SphA), from a genomic library (S. H. Lee, K. A. Kim, Y. K. Kim, I. W. Seong, M. J. Kim, and Y. J. Lee, Gene 254:19-28, 2000). Escherichia coli lysate harboring the sphH showed high hemolytic activities on sheep erythrocytes. However, it neither showed sphingomyelinase nor phospholipase activities, in contrast to SphA which was known to have sphingomyelinase activity. Interestingly, the SphH-mediated hemolysis on erythrocytes was osmotically protected by PEG 5000, suggesting that the SphH might have caused pore formation on the erythrocyte membrane. In the present study, we have prepared the Leptospira hemolysin SphH and investigated its hemolytic and cytotoxic activities on mammalian cells. SphH was shown to be a pore-forming protein on several mammalian cells: When treated with the SphH, the sheep erythrocyte membranes formed pores, which were morphologically confirmed by transmission electron microscopy. Furthermore, the SphH-mediated cytotoxicities on mammalian cells were demonstrated by the release of LDH and by inverted microscopic examinations. Finally, the immune serum against the full-length hemolysin could effectively neutralize the SphH-mediated hemolytic and cytotoxic activities. In conclusion, these results suggest that the virulence of Leptospira SphH was due to the pore formation on mammalian cell membranes.

  6. Leptospira interrogans in the genital tract of sheep. Research on ewes and rams experimentally infected with serovar hardjo (hardjobovis).

    Science.gov (United States)

    Farina, R; Cerri, D; Renzoni, G; Andreani, E; Mani, P; Ebani, V; Pedrini, A; Nuvoloni, R

    1996-07-01

    To verify if Leptospira hardjo can colonize the male and female genital organs of sheep, 9 animals (6 non pregnant ewes and 3 mature rams) were infected with a strain of L. hardjobovis recently recovered from the kidneys of a seropositive ewe. Postinfection controls (bacteriologic, serologic, immunohistochemistry and electron microscopy) failed to disclose the presence of leptospires in the uterus and oviducts, testicles, epididymis, prostate and bulbourethral glands of animals used for the experiment and slaughtered from 37 to 242 postinfection days. All animals showed a renal localization of L. hardjobovis lasting for the entire period of the study (over 8 months). These results emphasize the important role of sheep as maintenance hosts of the serovar.

  7. Seasonal prevalence of antibodies to Leptospira interrogans in Antillean manatees from a landlocked lake in Tabasco, Mexico.

    Science.gov (United States)

    Aragón-Martínez, Arianna; Olivera-Gómez, León D; Jiménez-Domínguez, Darwin

    2014-07-01

    Factors that alter the dynamics of ecologic systems can influence transmission of infectious diseases and may lead to decreases in natural populations. Leptospirosis is a cosmopolitan disease of zoonotic importance that affects most mammals. At the southern Gulf of Mexico, Antillean manatees (Trichechus manatus manatus) inhabit highly variable environments, with extended floods during the rainy season and drought conditions during the dry season that affect food availability and the thermal environment for manatees. We tested for changes in prevalence and titers of antibodies to 12 serovars of Leptospira interrogans in manatees between dry and rainy seasons. We determined titers for L. interrogans through microscopic agglutination tests (MAT) from 10 manatees, six during the dry season (DS), and six during the rainy season (RS) in Laguna de las Ilusiones, a landlocked lake hosting a population of about 20 manatees. All individuals were antibody positive (titers ≥ 100) to at least one serovar. The serovars bataviae, bratislava, canicola, and icterohaemorrhagiae had overall prevalences ≥ 50%; bataviae, bratislava, and canicola had prevalences ≥ 50% during both seasons. Serovars icterohaemorrhagiae and pyrogenes had prevalences ≥ 50% during DS and pomona, tarassovi, wolfii, and autumnalis during RS. Significant differences in prevalence between seasons were found for pomona, tarassovi, and autumnalis. Titers of tarassovi, wolfii, autumnalis, and bataviae were significantly higher during RS. There was a high prevalence of L. interrogans during the RS independent of high availability of plant foods, coinciding with the epizootiology of the bacteria that are endemic to tropical regions. Another factor possibly influencing prevalence is high anthropogenic pressure at the lake, causing an increase in potential sources of infection. Because of possible cross-reaction in MAT, further research is needed on the molecular discrimination of serovars in animals in the

  8. Signaling via ITGB1/FAK and microfilament rearrangement mediates the internalization of Leptospira interrogans in mouse J774A.1 macrophages

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    Zhao Xin

    2015-01-01

    Full Text Available Leptospirosis caused by pathogenic Leptospira species is a worldwide zoonotic 2 infectious disease, but the mechanisms of leptospiral internalization remain poorly understood. Here, we report that mouse J774A.1 macrophages expressed integrin-subfamily proteins (ITGB1, ITGB2 and ITGB3. Antibody blockage and siRNA-based knockdown of ITGB1 decreased the internalization of leptospires into mouse J774A.1 macrophage cells. The internalization required focal adhesion kinase (FAK activation in J774A.1 cells rather than phosphoinositide-3-kinase (PI3K, and microfilament rather than microtubule aggregation during infection. The data indicated that the ITGB1/FAK/microfilament signaling pathway is responsible for leptospiral internalization in mouse macrophages.

  9. Comparative proteogenomic analysis of the Leptospira interrogans virulence-attenuated strain IPAV against the pathogenic strain 56601

    Institute of Scientific and Technical Information of China (English)

    Yi Zhong; Yuan-Yuan Li; Xiu-Gao Jiang; Guo-Ping Zhao; Shengyue Wang; Yixue Li; Rong Zeng; Xuan Li; Xiao-Kui Guo; Xiao Chang; Xing-Jun Cao; Yan Zhang; Huajun Zheng; Yongzhang Zhu; Chengsong Cai; Zelin Cui; Yunyi Zhang

    2011-01-01

    The virulence-attenuated Leptospira interrogans serovar Lai strain IPAV was derived by prolonged laboratory passage from a highly virulent ancestral strain isolated in China. We studied the genetic variations of IPAV that render it avirulent via comparative analysis against the pathogenic L. interrogans serovar Lai strain 56601. The complete genome sequence of the IPAV strain was determined and used to compare with, and then rectify and reannotate the genome sequence of strain 56601. Aside from their highly similar genomic structure and gene order, a total of 33 insertions, 53 deletions and 301 single-nucleotide variations (SNVs) were detected throughout the genome of IPAV directly affecting 101 genes, either in their 5' upstream region or within their coding region. Among them, the majority of the [44]functional genes are involved in signal transduction, stress response, transmembrane transport and nitrogen metabolism. Comparative proteomic analysis based on quantitative liquid chromatography (LC)-MS/MS data revealed that among 1 627 selected pairs of orthologs, 174 genes in the IPAV strain were upregulated, with enrichment mainly in classes of energy production and lipid metabolism. In contrast, 228 genes in strain 56601 were upregulated, with the majority enriched in the categories of protein translation and DNA replication/repair. The combination of genomic and proteomic approaches illustrated that altered expression or mutations in critical genes, such as those encoding a Ser/Thr kinase, carbon-starvation protein CstA, glutamine synthetase, GTP-binding protein BipA, ribonucleotidediphosphate reductase and phosphate transporter, and alterations in the translational profile of lipoproteins or outer membrane proteins are likely to account for the virulence attenuation in strain IPAV.

  10. [Investigation of microbicidal activity of neutrophil defensins against leptospires].

    Science.gov (United States)

    Wu, Q; Xu, L; Wang, X; Li, S; Wang, B

    1992-06-01

    Defensins play an important role in oxygen-independent microbicidal mechanisms of neutrophils. They are effective against many bacteria, fungi and enveloped viruses. However, the effect of defensins upon leptospires has not been studied. In the present report, human defensins (i.e. HNP, a mixture of HNP1, HNP2 and HNP3 were prepared from human polymorphonuclear neutrophils by chromatography on Sephadex G-100 and then on Biogel P-10. Rabbit defensin NP1 was purified from rabbit peritoneal granulocytes by preparative acid urea polyacrylamide gel electrophoresis. By using the most-probable-number procedure, HNP and NP1 were tested in vitro for the killing of leptospira interrogans serogroup icteroheamorrhagiae serovar lai strain 017. NP1 was highly effective. When leptospires of strain 017 were incubated with 1 microgram/ml of NP1 at 30 degrees C for 4 hours, > 99% of these organisms were killed. HNP was less potent than NP1, and at 50 micrograms/ml, it killed > 90% of leptospires. As is also the case for the killing of bacteria, NP1 was active against leptospires in nutrient-free buffer, whereas HNP required the addition of glucose. The data suggest that defensins could play a major role in the killing of leptospires by neutrophils.

  11. Isolation of Salmonella enterica and serologic reactivity to Leptospira interrogans in opossums (Didelphis virginiana from Yucatán, México Aislamiento de Salmonella enterica y reactividad serológica a Leptospira interrogans en tlacuaches (Didelphis virginiana de Yucatán, México

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    Hugo Antonio RUIZ-PIÑA

    2002-07-01

    Full Text Available The presence of Salmonella enterica and serologic evidence of infection by Leptospira interrogans, were detected in the opossum Didelphis virginiana in a semi-urban locality of the Yucatán State, México. Ninety-one opossums were captured during the period April 1996 and May 1998. From a total of 17 feces samples, four Salmonella enterica subsp. enterica serotypes (Sandiego, Newport, Anatum, and Minnesota, and one Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:- were isolated. Some opossums presented mixed infections. From 81 sera samples, four (4.9% were positive to antibodies to Leptospira serovars pomona and wolfii. Both animals infected with Salmonella enterica and those serologically positive to Leptospira interrogans were captured in peridomestic habitat. Opossums infected with Salmonella enterica, were captured in dry season, and those seropositive to Leptospira interrogans during the rainy season. The implications of infection and reactivity of these zoonotic pathogens in D. virginiana in the Yucatan state are briefly discussed.La presencia de Salmonella enterica y evidencia serológica de infección por Leptospira interrogans fueron detectadas en tlacuaches de la especie Didelphis virginiana capturados en una localidad semi-urbana del estado de Yucatán, México. Se capturaron 91 marsupiales durante el período de abril de 1996 a mayo de 1998. De un total de 17 muestras de heces, se aislaron cuatro serotipos de Salmonella enterica subsp. enterica (Sandiego, Newport, Anatum y Minnesota y una Salmonella enterica subsp. arizonae serovar O44:Z4,Z23:-. En algunos tlacuaches se registraron infecciones mixtas. De 81 muestras de suero, cuatro (4,9% presentaron reacciones positivas con los serovares pomona y wolffi, ambos pertenecientes al género Leptospira. Los tlacuaches con serología positiva fueron capturados en el hábitat peridomiciliar. Los animales infectados con Salmonella enterica fueron capturados en los períodos de seca y

  12. Isolation and characterization of partially purified leptospiral antigens Isolamento e caracterização de antígenos parcialmente purificados de Leptospira

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    M.C. Koury

    1991-10-01

    Full Text Available The methanol extract of Leptospira interrogans serovar canicola was purified by precipitation with acetone or acetone and chloroform. The antigenicity of the antigen was not altered by heating or treatment with pepsin and pronase. However the antigenicity was lost when the antigen was treated with periodic acid. Chemical analysis revealed the presence of 40% carbohydrate (22% methylpentose, 28%; hexoses,4% protein, 20% lipid and 2,7% phosphate. The complement fixation test with sera from patients with leptospirosis agreed with the microscopic agglutination reaction.Extrato metílico de Leptospira interrogans sorovar canicola foi purificado por precipitação com acetona ou acetona e clorofórmio. A antigenicidade não foi alterada por aquecimento ou tratamento com pepsina e pronase, entretanto foi perdida quando o antígeno foi tratado com ácido periódico. Análise química revelou a presença de 40% de carboidrato (22% de metilpentose, 28% de hexose, 4% de proteína, 20% de lípide e 2,7% de fosfato. Reação de fixação de complemento realizada com soros de pacientes com leptospirose apresentou concordância com a reação de aglutinação microscópica.

  13. Occurrence of antibodies anti -Toxoplasma gondii, Neospora caninum and Leptospira interrogans in a captive deer herd in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Cristina Kraemer Zimpel

    Full Text Available Abstract A large number of Brazilian zoos keep many endangered species of deer, however, very few disease surveillance studies have been conducted among captive cervids. Blood samples from 32 Brazilian deer (Blastocerus dichotomus, Mazama nana and Mazama americana kept in captivity at Bela Vista Biological Sanctuary (Foz do Iguaçu, Brazil were investigated for 10 ruminant pathogens, with the aims of monitoring deer health status and evaluating any potential zoonotic risk. Deer serum samples were tested for Brucella abortus, Leptospira (23 serovars, Toxoplasma gondii, Neospora caninum, bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, foot-and-mouth disease virus, western equine encephalitis virus, eastern equine encephalitis virus and Venezuelan equine encephalitis virus. Antibodies against T. gondii (15.6%, N. caninum (6.2% and L. interrogans serogroup Serjoe (3.1% were detected. The serological results for all other infectious agents were negative. The deer were considered to be clinically healthy and asymptomatic regarding any disease. Compared with studies on free-ranging deer, the prevalences of the same agents tested among the captive deer kept at the Sanctuary were lower, thus indicating good sanitary conditions and high-quality management practices at the zoo.

  14. Occurrence of antibodies anti -Toxoplasma gondii, Neospora caninum and Leptospira interrogans in a captive deer herd in Southern Brazil.

    Science.gov (United States)

    Zimpel, Cristina Kraemer; Grazziotin, Ana Laura; de Barros Filho, Ivan Roque; Guimaraes, Ana Marcia de Sa; dos Santos, Leonilda Correia; de Moraes, Wanderlei; Cubas, Zalmir Silvino; de Oliveira, Marcos Jose; Pituco, Edviges Maristela; Lara, Maria do Carmo Custódio de Souza Hunold; Villalobos, Eliana Monteforte Cassaro; Silva, Lília Marcia Paulin; Cunha, Elenice Maria Sequetin; Castro, Vanessa; Biondo, Alexander Welker

    2015-01-01

    A large number of Brazilian zoos keep many endangered species of deer, however, very few disease surveillance studies have been conducted among captive cervids. Blood samples from 32 Brazilian deer (Blastocerus dichotomus, Mazama nana and Mazama americana) kept in captivity at Bela Vista Biological Sanctuary (Foz do Iguaçu, Brazil) were investigated for 10 ruminant pathogens, with the aims of monitoring deer health status and evaluating any potential zoonotic risk. Deer serum samples were tested for Brucella abortus, Leptospira (23 serovars), Toxoplasma gondii, Neospora caninum, bovine viral diarrhea virus, infectious bovine rhinotracheitis virus, foot-and-mouth disease virus, western equine encephalitis virus, eastern equine encephalitis virus and Venezuelan equine encephalitis virus. Antibodies against T. gondii (15.6%), N. caninum (6.2%) and L. interrogans serogroup Serjoe (3.1%) were detected. The serological results for all other infectious agents were negative. The deer were considered to be clinically healthy and asymptomatic regarding any disease. Compared with studies on free-ranging deer, the prevalences of the same agents tested among the captive deer kept at the Sanctuary were lower, thus indicating good sanitary conditions and high-quality management practices at the zoo.

  15. Cytotoxic activity and probable apoptotic effect of Sph2, a sphigomyelinase hemolysin from Leptospira interrogans strain Lai.

    Science.gov (United States)

    Zhang, Yi-Xuan; Geng, Yan; Yang, Jun-Wei; Guo, Xiao-Kui; Zhao, Guo-Ping

    2008-02-29

    Our previous work confirmed that Sph2/LA1029 was a sphigomyelinase-like hemolyisn of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai. Characteristics of both hemolytic and cytotoxic activities of Sph2 were reported in this paper. Sph2 was a heat-labile neutral hemolysin and had similar hemolytic behavior as the typical sphingomyelinase C of Staphylococcus aureus upon sheep erythrocytes. The cytotoxic activity of Sph2 was shown in mammalian cells such as BALB/C mouse lymphocytes and macrophages, as well as human L-02 liver cells. Transmission electron microscopic observation showed that the Sph2 treated BALB/C mouse lymphocytes were swollen and ruptured with membrane breakage. They also demonstrated condensed chromatin as a high-density area. Cytoskeleton changes were observed via fluorescence confocal microscope in Sph2 treated BALB/C mouse lymphocytes and macrophages, where both cytokine IL-1beta and IL-6 were induced. In addition, typical apoptotic morphological features were observed in Sph2 treated L-02 cells via transmission electron microscope and the percentage of apoptotic cells did increase after the Sph2 treatment detected by flow cytometry. Therefore, Sph2 was likely an apoptosis-inducing factor of human L-02 liver cells.

  16. A Dominant Clone of Leptospira interrogans Associated with an Outbreak of Human Leptospirosis in Thailand

    OpenAIRE

    Janjira Thaipadungpanit; Vanaporn Wuthiekanun; Wirongrong Chierakul; Smythe, Lee D.; Wimol Petkanchanapong; Roongrueng Limpaiboon; Apichat Apiwatanaporn; Slack, Andrew T; Yupin Suputtamongkol; White, Nicholas J.; Feil, Edward J.; Day, Nicholas P J; Peacock, Sharon J.

    2007-01-01

    BACKGROUND: A sustained outbreak of leptospirosis occurred in northeast Thailand between 1999 and 2003, the basis for which was unknown. METHODS AND FINDINGS: A prospective study was conducted between 2000 and 2005 to identify patients with leptospirosis presenting to Udon Thani Hospital in northeast Thailand, and to isolate the causative organisms from blood. A multilocus sequence typing scheme was developed to genotype these pathogenic Leptospira. Additional typing was performed for Leptosp...

  17. The enzyme-linked immunosorbent assay (ELISA) as a serological test for detecting antibodies against Leptospira interrogans serovar hardjo in sheep.

    Science.gov (United States)

    Adler, B; Faine, S; Gordon, L M

    1981-09-01

    The enzyme-liked immunosorbent assay (ELISA) was compared with the standard microscopic agglutination test (MAT) as a method for detecting antibodies against Leptospira interrogans serovar hardjo in sheep. Peak antibody levels detected by the 2 tests occurred at different times following experimental infection of sheep. In serums from flocks of sheep with naturally acquired infection there was a 95% correlation between MAT and ELISA with respect to the presence or absence of antibody to serovar hardjo, although the levels of correlation of the titres of the 2 tests was low. The 2 tests appeared to measure different antigen-antibody systems. The ELISA would be a useful test for screening large numbers of serums for antibodies to L. interrogans serovar hardjo.

  18. Leptospira Immunoglobulin-Like Protein B Interacts with the 20th Exon of Human Tropoelastin Contributing to Leptospiral Adhesion to Human Lung Cells

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    Ching-Lin Hsieh

    2017-05-01

    Full Text Available Leptospira immunoglobulin-like protein B (LigB, a surface adhesin, is capable of mediating the attachment of pathogenic leptospira to the host through interaction with various components of the extracellular matrix (ECM. Human tropoelastin (HTE, the building block of elastin, confers resilience and elasticity to lung, and other tissues. Previously identified Ig-like domains of LigB, including LigB4 and LigB12, bind to HTE, which is likely to promote Leptospira adhesion to lung tissue. However, the molecular mechanism that mediates the LigB-HTE interaction is unclear. In this study, the LigB-binding site on HTE was further pinpointed to a N-terminal region of the 20th exon of HTE (HTE20N. Alanine mutants of basic and aromatic residues on HTE20N significantly reduced binding to the LigB. Additionally, HTE-binding site was narrowed down to the first β-sheet of LigB12. On this binding surface, residues F1054, D1061, A1065, and D1066 were critical for the association with HTE. Most importantly, the recombinant HTE truncates could diminish the binding of LigB to human lung fibroblasts (WI-38 by 68%, and could block the association of LigA-expressing L. biflexa to lung cells by 61%. These findings should expand our understanding of leptospiral pathogenesis, particularly in pulmonary manifestations of leptospirosis.

  19. Prozone effects in microscopic agglutination tests for leptospirosis in the sera of mice infected with the pathogenic Leptospira interrogans serovar Canicola

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    Fabio Hiroto Shimabukuro

    2013-08-01

    Full Text Available Mice experimentally infected with a pathogenic strain of Leptospira interrogans serovar Canicola produced false negative results (prozone effect in a microscopic agglutination test (MAT. This prozone effect occurred in several serum samples collected at different post-infection times, but it was more prominent in samples collected from seven-42 days post-infection and for 1:50 and 1:100 sample dilutions. This phenomenon was correlated with increased antibody titres in the early post-infection phase. While prozone effects are often observed in serological agglutination assays for the diagnosis of animal brucellosis and human syphilis, they are not widely reported in leptospirosis MATs.

  20. Detection of Leptospira spp. in the semen and urine of bulls serologically reactive to Leptospira interrogans serovar hardjo Detecção de Leptospira spp. em sêmen e urina de touros sorologicamente reagentes a Leptospira interrogans sorovar hardjo

    Directory of Open Access Journals (Sweden)

    Fernanda Senter Magajevski

    2005-03-01

    Full Text Available This study evaluated PCR for the detection of leptospires in semen and urine of ten serologically reactive bulls, comparing these results with those obtained with other diagnosis techniques. Two collections of materials were done in alternate days. Semen and urine samples were separated in aliquots for: direct visualization in dark field microscopy; inoculation in hamsters (for semen only; isolation in culture media; and PCR. No hamster was positive by the microscopic agglutination test (MAT; kidney and liver fragments from the hamsters were used in an isolation attempt in culture media, with one positive isolation from the kidney of a hamster inoculated with semen of one bull, and from liver of hamsters inoculated with semen of three bulls. Isolation in culture was negative for all semen samples, but positive for five urine samples by direct inoculation. In PCR there was no positive result for semen samples, and only one urine sample was positive, which was coincident with one of the positive cultures. It was not possible to visualize leptospires in any of the samples by dark field microscopy.O presente trabalho avaliou a PCR na detecção de leptospiras em sêmen e urina de dez touros sorologicamente reagentes, comparando seus resultados com aqueles obtidos por outras técnicas de diagnóstico. Foram realizadas duas colheitas de materiais em dias alternados. As amostras de sêmen e de urina foram separadas em alíquotas para visualização direta em microscopia de campo escuro, inoculação em hamsters (apenas para o sêmen, isolamento em meio de cultura e PCR. Nenhum hamster apresentou positividade na prova de soroaglutinação microscópica (SAM; fragmentos de rins e fígado desses animais foram utilizados para a tentativa de isolamento em meio de cultura, sendo positivo o cultivo a partir do rim de hamster inoculado com semen de um touro, e do fígado de hamsters inoculados com o semen de três touros. O isolamento em meio de cultura foi

  1. Prevalence of Leptospira interrogans antibodies in free-ranging Tayassu pecari of the Southern Pantanal, Brazil, an ecosystem where wildlife and cattle interact.

    Science.gov (United States)

    de Freitas, Tatiana P Tavares; Keuroghlian, Alexine; Eaton, Donald P; de Freitas, Emanuel Barbosa; Figueiredo, Aline; Nakazato, Luciano; de Oliveira, Jacqueline M; Miranda, Flávia; Paes, Rita Cassia S; Monteiro, Leticia A R Carneiro; Lima, José Vergílio B; da C Neto, Aparecida A; Dutra, Valéria; de Freitas, Julio Cesar

    2010-12-01

    We surveyed a wild population of white-lipped peccaries (Tayassu pecari) in the Brazilian Pantanal for evidence of Leptospira interrogans. Serum samples from 71 free-ranging T. pecari were obtained between 2003 and 2005 in the southern Pantanal of Mato Grosso do Sul state. We used microscopic microagglutination to test for antibodies against 14 L. interrogans serovars (antibody titers ≥ 1:100 were considered seropositive). Seventy percent of captured animals tested positive for leptospirosis antibodies. Antibodies against icterohaemorrhagiae and autumnalis serovars were the most prevalent. We used log-linear analyses to test for associations among seropositivity, age class, and sex of captured animals. Seropositivity was strongly associated with animal age class, but independent of sex. Forty-six percent of animals less than 2 years old, 63% of adults during peak reproductive years, and 100% of the oldest age class were seropositive. A nonparametric multivariate procedure (MRPP) showed that the composition of serovar antibody types changed with age, and ANOVA models demonstrated that antibody titers increased with age, suggesting long-term exposure to a greater number and variety (i.e., serovar types) of L. interrogans infections. This study presents the first quantitative survey of antibodies against L. interrogans serovars in a T. pecari population of the Pantanal. The high prevalence of leptospirosis antibodies in free-ranging white-lipped peccaries and the potential impacts on reproduction and population dynamics emphasize the need for further studies investigating the roles of Pantanal wildlife and livestock in the transmission and maintenance of L. interrogans in the environment.

  2. Leptospira interrogans activation of peripheral blood monocyte glycolipoprotein demonstrated in whole blood by the release of IL-6

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    F. Dorigatti

    2005-06-01

    Full Text Available Glycolipoprotein (GLP from pathogenic serovars of Leptospira has been implicated in the pathogenesis of leptospirosis by its presence in tissues of experimental animals with leptospirosis, the inhibition of the Na,K-ATPase pump activity, and induced production of cytokines. The aims of the present study were to investigate the induction of IL-6 by GLP in peripheral blood mononuclear cells (PBMC and to demonstrate monocyte stimulation at the cellular level in whole blood from healthy volunteers. PBMC were stimulated with increasing concentrations (5 to 2500 ng/ml of GLP extracted from the pathogenic L. interrogans serovar Copenhageni, lipopolysaccharide (positive control or medium (negative control, and supernatants were collected after 6, 20/24, and 48 h, and kept at -80ºC until use. Whole blood was diluted 1:1 in RPMI medium and cultivated for 6 h, with medium, GLP and lipopolysaccharide as described above. Monensin was added after the first hour of culture. Supernatant cytokine levels from PBMC were measured by ELISA and intracellular IL-6 was detected in monocytes in whole blood cultures by flow-cytometry. Monocytes were identified in whole blood on the basis of forward versus side scatter parameters and positive reactions with CD45 and CD14 antibodies. GLP ( > or = 50 ng/ml-induced IL-6 levels in supernatants were detected after 6-h incubation, reaching a peak after 20/24 h. The percentage of monocytes staining for IL-6 increased with increasing GLP concentration. Thus, our findings show a GLP-induced cellular activation by demonstrating the ability of GLP to induce IL-6 and the occurrence of monocyte activation in whole blood at the cellular level.

  3. Proteína LIC10494 de Leptospira interrogans serovar Copenhageni: modelo estructural y regiones funcionales asociadas

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    Orlando Emilio Acevedo

    2012-04-01

    Full Text Available Protein LIC10494 of Leptospira interrogans serovar Copenhageni: structural model and associated functional regions. Objective.Predict by computational means the 3D structure of the antigenic protein LIC10494 and report associated important functional regionsfor its pathogenicity and immunogenicity. Materials and methods. We performed a computational analysis of the primary structure ofLIC10494 using the servers BLAST, PROTPARAM, PROTSCALE, DAS, SOSUI, TOPPRED, TMAP, TMpred, SPLIT4, PHDHTM,TMHMM2, HMMTOP2, GLOBPLOT and PROSITE. The secondary structure was obtained by consensus of the algorithms SOPM,PREDATOR GOR4, DPM and DSC. The approach to the tertiary structure was obtained using the algorithm MUSTER. The energyminimization was done using the AMBER94 force field of the Schrodinger suite of molecular analysis, and the stereochemistry andenergy model validation was performed by the RAMPAGE server. The final model was visualized using PyMol V.0,98. Results. Thisstudy proposes a computational model that describes the 3D structure of the hypothetical lipoprotein LIC10494 and agrees with previousexperimental reports; thus, our study demonstrates the existence of patterns that could play an important role in the pathogenicity andprotection of the bacteria against the host immune system; the presence of a disorganized region between amino acids 80 and 140, andof a transmembrane segment between amino acids 8 and 22. Conclusion. The coincidence between structural and functional segments suggests that our model can be used to predict certain aspects of the biological behaviour of the protein according to the pathogenic andimmunogenic characteristics of the bacteria.

  4. SEROPREVALENCE OF NINE LEPTOSPIRA INTERROGANS SEROVARS IN WILD CARNIVORES, UNGULATES, AND PRIMATES FROM A ZOO POPULATION IN A METROPOLITAN REGION OF CHILE.

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    Moreno-Beas, Eduardo; Abalos, Pedro; Hidalgo-Hermoso, Ezequiel

    2015-12-01

    Serum samples from 130 individuals representing 42 species of carnivores, ungulates, and primates from a population of captive mammals in Metropolitan Region in Chile were tested for antibodies against nine serovars of Leptospira interrogans using the microscopic agglutination test. Ten percent of the animals were seropositive to one or more serovars. Seroprevalence was significantly higher in ungulates (20.4%) compared to carnivores (3.8%) and primates (3.4%). There were no significant differences in seroprevalence among sex and age ranges. The most frequent serovar detected was Autumnalis, present in 53.4% of antibody-positive animals. Most positive animals had titers of ≤1 : 200, except for a maned wolf ( Chrysocyon brachyurus ) with titers of 1 : 400 against serovar Hardjo. To the authors' knowledge, this is the first report of Leptospira exposure detected in native endangered pudu ( Pudu puda ) and the first confirmation of exposure to L. interrogans in captive wild mammals in Chile. Leptospirosis should be considered as a differential diagnosis in future disease presentation for hepatitis or abortions in captive mammals in Chile.

  5. Direct detection and differentiation of pathogenic Leptospira species using a multi-gene targeted real time PCR approach.

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    Ferreira, Ana Sofia; Costa, Pedro; Rocha, Teresa; Amaro, Ana; Vieira, Maria Luísa; Ahmed, Ahmed; Thompson, Gertrude; Hartskeerl, Rudy A; Inácio, João

    2014-01-01

    Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpeteresenii and L. noguchii, which constitute the veterinary most relevant pathogenic species of Leptospira. The method uses sets of species-specific probes, and respective flanking primers, designed from ompL1 and secY gene sequences. To monitor the presence of inhibitors, a duplex amplification assay targeting both the mammal β-actin and the leptospiral lipL32 genes was implemented. The analytical sensitivity of all primer and probe sets was estimated to be leptopirosis.

  6. Functional thioredoxin reductase from pathogenic and free-living Leptospira spp.

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    Sasoni, Natalia; Iglesias, Alberto A; Guerrero, Sergio A; Arias, Diego G

    2016-08-01

    Low molecular mass thiols and antioxidant enzymes have essential functions to detoxify reactive oxygen and nitrogen species maintaining cellular redox balance. The metabolic pathways for redox homeostasis in pathogenic (Leptospira interrogans) and free-living (Leptospira biflexa) leptospires species were not functionally characterized. We performed biochemical studies on recombinantly produced proteins to in depth analyze kinetic and structural properties of thioredoxin reductase (LinTrxR) and thioredoxin (LinTrx) from L. interrogans, and two TrxRs (LbiTrxR1 and LbiTrxR2) from L. biflexa. All the TrxRs were characterized as homodimeric flavoproteins, with LinTrxR and LbiTrxR1 catalyzing the NADPH dependent reduction of LinTrx and DTNB. The thioredoxin system from L. interrogans was able to use glutathione disulfide, lipoamide disulfide, cystine and bis-γ-glutamyl cysteine and homologous peroxiredoxin as substrates. Classic TrxR activity of LinTrxR2 had not been evidenced in vitro, but recombinant Escherichia coli cells overexpressing LbiTrxR2 showed high tolerance to oxidative stress. The enzymatic systems herein characterized could play a key role for the maintenance of redox homeostasis and the function of defense mechanisms against reactive oxidant species in Leptospira spp. Our results contribute to the general knowledge about redox biochemistry in these bacteria, positioning TrxR as a critical molecular target for the development of new anti-leptospiral drugs.

  7. Efficacy of the Rabbit Polyclonal Anti-leptospira Antibody against Homotype or Heterotype Leptospira Infection in Hamster

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    Ding, Zhuang; Wang, Hai; Wu, Dianjun; Xie, Xufeng; Lin, Tao; Fu, Yunhe; Zhang, Naisheng; Cao, Yongguo

    2016-01-01

    Leptospirosis, caused by Leptospira, is one of the most important of neglected emerging zoonotic diseases that has important impacts on public health worldwide. Polyclonal antibody (pcAb) therapy is a potential method to process a series of pathogens for which there are limited determination of treatment, such as leptospirosis. First, we evaluated the efficacy of pcAb, derived from the sera of rabbits inoculated with Leptospira, against homotype (Leptospira interrogans serovar Lai) or heterotype (Leptospira interrogans serovar Autumnalis) Leptospira infection in a lethal hamster model. The pcAb treatment improved survival compared to the controls. The histopathology’s of the infected kidney, liver and lung were also examined by hematoxylin and eosin staining. Using real-time quantitative PCR, we determined that most of the leptospires in the primary organs were almost completely removed by pcAb. In the second experiment, treatments, including antibiotic, pcAb, and combination, were started immediately after occurrence of the first serious sickness mouse in any group. No significant difference in survival rate between pcAb group and antibiotic group was found, but the combination therapy group significantly improved survival rate compared to the others (Phamster, and combination therapy improved survival compared to antibiotic group in the late treatment of homotype leptospirosis. PMID:28027297

  8. Prevalence of antibodies against Leptospira sp. in snakes, lizards and turtles in Slovenia

    Science.gov (United States)

    2013-01-01

    Background Leptospiral infections in poikilothermic (cold blooded) animals have received very little attention and the literature concerning natural infections of these animals is limited. The aim of this study was to determine the prevalence of leptospiral antibodies in reptiles, imported into Slovenia and intended to be pets in close contact with humans. A total of 297 reptiles (22 snakes, 210 lizards and 65 turtles) were tested for specific antibodies against serovars of Leptospira interrogans sensu stricto using the microscopic agglutination test (MAT). Live cultures of different serovars were used as antigens. MAT was performed according to standard procedures and the degree of reaction was interpreted by estimating the percentage of agglutinated leptospires. Samples showing titres of ≥ 50 against one or more serovars were considered as positive. Results Antibodies against seven pathogenic serovars of L. interrogans sensu stricto were detected in 46 of 297 reptiles. Among 22 snakes, specific antibodies against pathogenic serovars of three Leptospira species (L. interrogans, L. kirschneri and L. borgpetersenii) at titre levels from 1:50 to 1:400 were detected in 6 snakes. In 31 of 210 lizards, specific antibodies were found in titres from 1:50 to 1:1000 and, finally, among 65 turtles (terrapins and tortoises), 9 had specific antibodies at titre levels between 1:50 and 1:1600. Animals imported from non-EU countries showed significantly higher prevalence (25.0%; 95 confidence interval: 16.7–33.3%) than animals from EU member states (10.4%; confidence interval: 6.1–14.7%). Conclusions Reptiles may be considered as potential reservoirs of L. interrogans sensu stricto. Origin of the animals is a risk factor for presence of leptospiral antibodies, especially in lizards. Special attention should be focused on animals from non-EU member states. PMID:24020619

  9. Comparison of four antibiotics for inactivating leptospires in bull semen diluted in egg yolk extender and experimentally inoculated with Leptospira santarosai serovar guaricura Comparação de quatro antibióticos para inativar leptospiras em sêmen bovino diluído em gema-citrato e experimentalmente contaminado com Leptospira santarosai sorovar guaricura

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    Fabiana Miraglia

    2003-06-01

    Full Text Available Inactivation of leptospires in pools of semen from three Holstein Friesian bulls, collected in an artificial vagina, was investigated. Spermatic concentration was adjusted in egg yolk citrate extender, submitted to the following treatments: A (control; without antibiotics; B (penicillin, 1,000 UI/mL - streptomycin, 1,000 µg/mL; C (amoxicillin, 1,000 µg/mL; D (ceptiofur sodium, 1,000 µg/mL; E (amoxicillin 1,000 µg/mL - ceptiofur sodium 1,000 µg/mL. Leptospires (2.0 x 10(6 leptospires/mL were added into the diluted semen. Recovery of leptospires was obtained in modified EMJH semi-solid medium with and without antibiotics. The antibiotics in the concentrations used did not affect means of percentage of progressive motility and individual progressive motility of spermatozoids. Penicillin-streptomycin presented the best results in leptospire inactivation (97.1%. Amoxicillin, ceptiofur sodium and their combination at the concentrations studied presented poor results: 59.29%; 32.5% and 60.36% of inactivation, being less effective in leptospire inactivation than penicillin-streptomycin.A inativação de leptospiras em misturas de sêmen, obtidas através de vagina artificial, de três touros holandeses, foi estudada. A concentração espermática foi ajustada em diluidor gema-citrato utilizando os seguintes tratamentos: A (controle; sem antibióticos; B (penicilina, 1000 UI/mL - estreptomicina, 1000 µg/mL; C (amoxicilina, 1000 µg/mL; D (ceftiofur sódico, 1000 µg/mL; E (amoxicilina 1000 µg/mL - ceftiofur sódico 1000 µg/mL. Leptospiras (2,0x10(6 leptospiras/mL foram adicionadas ao sêmen diluído. A recuperação das leptospiras foi obtida em meio EMJH modificado semi-sólido, com e sem antibióticos. As médias da porcentagem de motilidade progressiva e a de motilidade individual progressiva dos espermatozóides não foram afetadas pelos antibióticos nas concentrações usadas. Penicilina-estreptomicina apresentou os melhores resultados na

  10. Detection of Leptospira interrogans DNA and antigen in fixed equine eyes affected with end-stage equine recurrent uveitis.

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    Pearce, Jacqueline W; Galle, Laurence E; Kleiboeker, Steve B; Turk, James R; Schommer, Susan K; Dubielizig, Richard R; Mitchell, William J; Moore, Cecil P; Giuliano, Elizabeth A

    2007-11-01

    Equine recurrent uveitis (ERU) is the most frequent cause of blindness in horses worldwide. Leptospira has been implicated as an etiologic agent in some cases of ERU and has been detected in fresh ocular tissues of affected horses. The objective of this study was to determine the presence of Leptospira antigen and DNA in fixed equine ocular tissues affected with end-stage ERU. Sections of eyes from 30 horses were obtained. Controls included 1) 10 normal equine eyes and 2) 10 equine eyes with a nonrecurrent form of uveitis. The experimental group consisted of 10 eyes diagnosed with ERU based on clinical signs and histologic lesions. Sections were subjected to immunohistochemical staining with an array of rabbit anti-Leptospira polyclonal antibodies. DNA extractions were performed by using a commercial kit designed for fixed tissue. Real-time PCR analysis was completed on extracted DNA. The target sequence for PCR was designed from alignments of available Leptospira 16S rDNA partial sequences obtained from GenBank. Two of 10 test samples were positive for Leptospira antigen by immunohistochemical assay. Zero of 20 controls were positive for Leptospira antigen. All test samples and controls were negative for Leptospira DNA by real-time PCR analysis. Leptospira was detected at a lower frequency than that previously reported for fresh ERU-affected aqueous humor and vitreous samples. Leptospira is not frequently detectable in fixed ocular tissues of horses affected with ERU when using traditional immunohistochemical and real-time PCR techniques.

  11. Seropositivity to Leptospira interrogans serovar Bratislava associated to reproductive problems without significant biochemical or hematological alterations in horses Soropositividade para Leptospira interrogans serovar Bratislava associada a falhas reprodutivas sem alterações hematológicas e bioquímicas significativas em cavalos

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    Melissa Pinna

    2010-10-01

    Full Text Available The objective was to study haematological and biochemical alterations associated to seropositivity to Leptospira interrogans serovar Bratislava infection in horses with reproductive alterations, such as neonatal deaths, embryonic deaths and abortions. A flock of mares with poor reproductive performance was studied. Eighty-two (58.6% were seropositive (titre 200; 72 of those (87.8% for Bratislava. Slight haematological and biochemical alterations were observed, being more frequent (PO objetivo deste trabalho foi estudar alterações hematológicas e bioquímicas associadas à soropositividade para Leptospira interrogans sorovar Bratislava em cavalos com alterações reprodutivas, tais como mortes neonatais, absorção embrionária e abortamentos. Um rebanho de éguas com baixos índices reprodutivos foi estudado. Oitenta e duas (58,6% foram soropositivas (títulos 200, sendo 72 destas (87,8% para Bratislava. Foram observadas poucas alterações hematológicas e bioquímicas, mais frequentes (P<0,05 em éguas soropositivas do que soronegativas. Cavalos soropositivos para Bratislava não tinham alterações graves nos valores hematológicos e bioquímicos. Esses achados reforçam que esse sorovar seja adaptado de cavalos e cause apenas sintomas brandos, associados a falhas reprodutivas.

  12. Effect of exposure to Neospora caninum, Salmonella, and Leptospira interrogans serovar Hardjo on the economic performance of Irish dairy herds.

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    O' Doherty, E; Sayers, R; O' Grady, L; Shalloo, L

    2015-04-01

    The objective of the current study was to quantify the effects of exposure to Salmonella, Neospora caninum, and Leptospira interrogans serovar Hardjo (L. hardjo) on dairy farm profitability and to simulate the effect of vaccination for Salmonella and L. hardjo on dairy farm profitability. The production effects associated with exposure to each of these pathogens in study herds were defined under 3 categories: (1) milk production effects, (2) reproduction effects (including culling), and (3) mortality effects. The production effects associated with exposure to Salmonella, N. caninum, and L. hardjo were incorporated into the Moorepark Dairy Systems Model. In the analysis, herds negative for exposure to Salmonella, N. caninum, and L. hardjo were assumed baseline herds, with all results presented relative to this base. In simulations examining the effect of vaccination for Salmonella and L. hardjo on farm profitability, vaccinated herds (vaccination costs included) were considered as baseline herds and results were presented relative to this base. Total annual profits in unvaccinated herds were reduced by €77.31, €94.71, and €112.11 per cow at milk prices of €0.24, €0.29, and €0.34/L, respectively, as a result of exposure to Salmonella. In the current study, herds positive for exposure to Salmonella recorded a 316-kg reduction in milk yield, whereas no association was detected between exposure to N. caninum or L. hardjo and milk production. Exposure to both N. caninum and L. hardjo was associated with compromised reproductive performance. Herds positive for exposure to N. caninum and Salmonella had greater rates of adult cow mortality and calf mortality, respectively. Vaccination for both Salmonella and L. hardjo was associated with improved performance in study herds. Exposure to N. caninum resulted in a reduction in annual farm profits of €11.55, €12, and €12.44 per cow at each milk price, whereas exposure to L. hardjo resulted in a reduction in

  13. Genotyping of Leptospira directly in urine samples of cattle demonstrates a diversity of species and strains in Brazil.

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    Hamond, C; Pestana, C P; Medeiros, M A; Lilenbaum, W

    2016-01-01

    The aim of this study was to identify Leptospira in urine samples of cattle by direct sequencing of the secY gene. The validity of this approach was assessed using ten Leptospira strains obtained from cattle in Brazil and 77 DNA samples previously extracted from cattle urine, that were positive by PCR for the genus-specific lipL32 gene of Leptospira. Direct sequencing identified 24 (31·1%) interpretable secY sequences and these were identical to those obtained from direct DNA sequencing of the urine samples from which they were recovered. Phylogenetic analyses identified four species: L. interrogans, L. borgpetersenii, L. noguchii, and L. santarosai with the most prevalent genotypes being associated with L. borgpetersenii. While direct sequencing cannot, as yet, replace culturing of leptospires, it is a valid additional tool for epidemiological studies. An unexpected finding from this study was the genetic diversity of Leptospira infecting Brazilian cattle.

  14. Efecto booster de una inmunización activa con Leptospira interrogans serogrupo Ballum en hámsters vacunados con vax-SPIRAL®

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    Andrés González

    2003-06-01

    Full Text Available Se evaluó en hámsters la inmunidad cruzada y capacidad protectora conferidas por la vacuna antileptospirósica trivalente vax-SPIRAL® frente a Leptospira interrogans serogrupo Ballum, así como el efecto de una inmunización activa con preparación vacunal monovalente de Ballum en animales previamente inmunizados con la vacuna trivalente. La respuesta IgG específica a Ballum, Canicola, Icterohaemorrhagiae y Pomona inducida tras cada inmunización se determinó mediante un sistema ELISA cuantitativo de células enteras. La capacidad de protección heteróloga de vax-SPIRAL® se evaluó frente al reto con 100 y 10 000 DL50 de dos cepas clínicas de Ballum altamente virulentas. Tras 14 días de culminado el esquema de inmunización la vacuna trivalente indujo un 100% de seroconversión de IgG específica a Ballum en los animales inmunizados y una total protección cruzada frente a la infección letal y la prevalencia de leptospiras en hígado y riñón. La aplicación de una única dosis de preparación monovalente de Ballum tras 6 semanas de culminado el esquema de inmunización de vax-SPIRAL® reforzó la inmunidad frente a los cuatro serogrupos de Leptospira de mayor circulación en humanos en Cuba.

  15. Leptospira Species in Feral Cats and Black Rats from Western Australia and Christmas Island.

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    Dybing, Narelle A; Jacobson, Caroline; Irwin, Peter; Algar, David; Adams, Peter J

    2017-05-01

    Leptospirosis is a neglected, re-emerging bacterial disease with both zoonotic and conservation implications. Rats and livestock are considered the usual sources of human infection, but all mammalian species are capable of carrying Leptospira spp. and transmitting pathogenic leptospires in their urine, and uncertainty remains about the ecology and transmission dynamics of Leptospira in different regions. In light of a recent case of human leptospirosis on tropical Christmas Island, this study aimed to investigate the role of introduced animals (feral cats and black rats) as carriers of pathogenic Leptospira spp. on Christmas Island and to compare this with two different climatic regions of Western Australia (one island and one mainland). Kidney samples were collected from black rats (n = 68) and feral cats (n = 59) from Christmas Island, as well as feral cats from Dirk Hartog Island (n = 23) and southwest Western Australia (n = 59). Molecular (PCR) screening detected pathogenic leptospires in 42.4% (95% confidence interval 29.6-55.9) of cats and 2.9% (0.4-10.2) of rats from Christmas Island. Sequencing of cat- and rat-positive samples from Christmas Island showed 100% similarity for Leptospira interrogans. Pathogenic leptospires were not detected in cats from Dirk Hartog Island or southwest Western Australia. These findings were consistent with previous reports of higher Leptospira spp. prevalence in tropical regions compared with arid and temperate regions. Despite the abundance of black rats on Christmas Island, feral cats appear to be the more important reservoir species for the persistence of pathogenic L. interrogans on the island. This research highlights the importance of disease surveillance and feral animal management to effectively control potential disease transmission.

  16. Multilocus sequence typing (MLST) of leptospiral strains isolated from two geographic locations of Tamil Nadu, India.

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    Kanagavel, Murugesan; Princy Margreat, Alphonse Asirvatham; Arunkumar, Manivel; Prabhakaran, Shanmugarajan Gnanasekaran; Shanmughapriya, Santhanam; Natarajaseenivasan, Kalimuthusamy

    2016-01-01

    Here the rodent carrier status for the transmission of human leptospirosis in Tiruchirappalli, district, Tamil Nadu, India was assessed. The predominantly circulating leptospiral STs were recognized by multilocus sequence typing (MLST). A total of 113 rodents were trapped from different provinces of the Tiruchirappalli district. The most prevalent rodent was Bandicota bengalensis (37.2%), and of the total, 52.2% (n=59) rodents were found to be positive for leptospiral 16S rRNA. These results were validated with a leptospiral culture positivity of 45.8% (n=27). Three isolates from Chennai (2 rodents and 1 human) and 1 human isolate from Tiruchirappalli were included to understand the spatial variations and to track the source of human leptospirosis. The serogroup, serovar, and species level identification of all 31 isolates identified 28 to be Leptospira borgpetersenii serovar Javanica and three as Leptospira interrogans serovar Autumnalis. MLST analysis defined all isolates to the existing ST profiles (ST145 and ST27) with the exception of 6 L. borgpetersenii (ST DR) isolates that showed variations in the sucA and pfkB loci. The DR ST was locally confined to Chatram province of Tiruchirappalli suggesting an epidemiological link. The predominant STs, ST145 and ST-DR form a group, indicating the presence of original strain that subsequently diverged evolutionarily into two STs. The variations between L. borgpetersenii in sucA and pfkB loci may be an indication that evolutionary changes transpired in Tiruchirappalli.

  17. Analysis of Leptospira interrogans ompA gene and immunological identification of its recombinant expression product%问号钩端螺旋体ompA基因分析及其重组表达产物的免疫学鉴定

    Institute of Scientific and Technical Information of China (English)

    丁威; 董海艳; 薛峰; 严杰; 楼永良

    2009-01-01

    Objective To investigate the distribution of ompA gnne in 15 Chinese reference standard strains belonging to 15 serogroups of Leptospira interrogate, and to express recombinant OmpA ( rOmpA ) and to identify immunogenicity and immunoprotection of rOmpA. Methods Genomic DNAs from different leptospiral strains were extracted by phenol-chloroform method. Entire ompA gene fragments from the strains were amplified by PCR and then sequenced after T-A cloning. A prokaryotic expression system of ompA gene from L. interrogans strain 56601 was constructed, and the expression and yield of rOmpA were determined by SOS-PAGE plus Bio-Rad Agarose Image Analyser. Rabbits were immunized with rOmpA for obtaining antiserum, and immunodiffusion test was used to measure the antiserum's titer. Western blot assay was performed to determine the immunoreaetivity of rOmpA with the antiserum against rOmpA and antiserum against whole cell of L. interrogans strain 56601, while mi-croscopic agglutination test (MAT) was applied to detect the cross agglutination to the 15 L. interrogans strains. A leptospire adhering cell model and a leptospire infecting guinea pigs model were used to determine the adhesion-bloc-king effect of rOmpA antiserum and immunoprotection of rOmpA. Results All the 15 L. interrogans strains, but not L. biflexa strain Patoe Ⅰ , had sequence conserved ompA genes. The yield of rOmpA was approximate 20% of the total bacterial proteins, rOmpA could induce rabbits to produce antibody and immunodiffusion titer of the anti-serum was 1:4. Both antisera against rOmpA and against whole cell of L. interrogans strain 56601 were able to pro-duce positive Western blot signs to rOmpA, and the former offered 1 : 20-1 : 320 MAT titers to the 15 L. interrogans strains. 1: 10-1:160 dilutions of rOmpA antiserum could efficiently block L. interrogans strain 56601 adhering to J774A. 1 cells, and 100 μg and 200 μg rOmpA displayed 50.0% and 75.0% immunoprotective rates in the infee-ted guinea

  18. Detection of virulence factors and molecular typing of pathogenic Leptospira from capybara (Hydrochaeris hydrochaeris).

    Science.gov (United States)

    Jorge, Sérgio; Monte, Leonardo G; Coimbra, Marco Antonio; Albano, Ana Paula; Hartwig, Daiane D; Lucas, Caroline; Seixas, Fabiana K; Dellagostin, Odir A; Hartleben, Cláudia P

    2012-10-01

    Leptospirosis is a globally prevalent zoonosis caused by pathogenic Leptospira spp.; several serologic variants have reservoirs in synanthropic rodents. The capybara is the largest living rodent in the world, and it has a wide geographical distribution in Central and South America. This rodent is a significant source of Leptospira since the agent is shed via urine into the environment and is a potential public health threat. In this study, we isolated and identified by molecular techniques a pathogenic Leptospira from capybara in southern Brazil. The isolated strain was characterized by partial rpoB gene sequencing and variable-number tandem-repeats analysis as L. interrogans, serogroup Icterohaemorrhagiae. In addition, to confirm the expression of virulence factors, the bacterial immunoglobulin-like proteins A and B expression was detected by indirect immunofluorescence using leptospiral specific monoclonal antibodies. This report identifies capybaras as an important source of infection and provides insight into the epidemiology of leptospirosis.

  19. Detección de proteínas de adhesión a fibronectina y colágeno presentes en Leptospira interrogans serovar Canicola

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    Gisele Reyes

    2007-12-01

    Full Text Available Como parte de los estudios encaminados a la obtención de una formulación vacunal por subunidades contra la leptospirosis humana, se describe la purificación y caracterización de las proteínas de unión a fibronectina y a colágeno en Leptospira interrogans. Las proteínas de la membrana externa fueron extraídas mediante la solubilización con Tritón X-114 y se aplicaron en una columna de afinidad de IgG AntiBSA-Sepharose 2B CL, para eliminar la BSA, contaminante principal del medio de cultivo en que crece el microorganismo. La muestra libre de BSA (no fijado se aplicó a una columna de afinidad de fibronectina Sepharose 4B-CNBr, que permitió la separación y detección de una fracción que contenía una proteína de unión a fibronectina presente en la cepa 87 de Leptospira interrogans serovar Canicola, cuyo peso molecular fue estimado en 40 kDa. La proteína aislada demostró ser antigénica y conservada en los serovares Canicola, Copenhageni y Mozdok, en el ensayo de inmunodetección utilizado en este estudio (Dot blot. Para ello se utilizaron sueros específicos obtenidos en ratas infectadas experimentalmente con cada serovar y una mezcla de sueros de humanos convalecientes de leptospirosis. Las proteínas de membrana externa solubilizadas con Tritón X-114, libres de BSA, fueron aplicadas también a una columna de afinidad colágeno-Sepharosa 4B-CNBr, que permitió la purificación de una proteína de unión a colágeno con un peso molecular de aproximadamente 25 kDa, la cual resultó ser antigénica frente a sueros de humanos convalecientes de la enfermedad. Ambas proteínas seleccionadas (40 kD y 25 kD podrían ser evaluadas como posibles inmunógenos en futuros estudios encaminados a la obtención de nuevos antígenos vacunales.

  20. Isolation and characterization of Leptospira spp. from raccoons in Japan.

    Science.gov (United States)

    Koizumi, Nobuo; Uchida, Masaki; Makino, Takashi; Taguri, Toshitsugu; Kuroki, Toshiro; Muto, Maki; Kato, Yukio; Watanabe, Haruo

    2009-04-01

    We investigated whether raccoons (Procyon lotor) carried leptospires in their kidneys in Japan. Leptospira was isolated from 2 of 71 raccoons captured in Kanagawa Prefecture and 1 of 53 raccoons at a zoological park in Nagasaki Prefecture. Anti-Leptospira antibodies were detected in 16 of 124 raccoons (12.9%) in Kanagawa and 33 of 53 raccoons (62.3%) in Nagasaki, respectively. The partial nucleotide sequences of their flaB genes suggested that the isolates belonged to L. interrogans. The serovars of the isolates were identified as Copenhageni/Icterohaemorrhagiae (1 strain in Kanagawa) and Hebdomadis (1 strain both in Kanagawa and Nagasaki) by reactivity with the reference antisera and restriction fragment length polymorphism (RFLP) analysis based on pulsed-field gel electrophoresis and cross-agglutination-absorption test, respectively. RFLP analysis on the serovars Hebdomadis strains revealed genetic diversity among serovar Hebdomadis. Although it is unclear if the raccoons carried leptospires in their kidneys at the time imported, there is no doubt that imported animals are a new reservoir animal of leptospires in Japan.

  1. The development of a real-time PCR to detect pathogenic Leptospira species in kidney tissue.

    Science.gov (United States)

    Fearnley, C; Wakeley, P R; Gallego-Beltran, J; Dalley, C; Williamson, S; Gaudie, C; Woodward, M J

    2008-08-01

    A LightCycler real-time PCR hybridization probe-based assay that detects a conserved region of the16S rRNA gene of pathogenic but not saprophytic Leptospira species was developed for the rapid detection of pathogenic leptospires directly from processed tissue samples. In addition, a differential PCR specific for saprophytic leptospires and a control PCR targeting the porcine beta-actin gene were developed. To assess the suitability of these PCR methods for diagnosis, a trial was performed on kidneys taken from adult pigs with evidence of leptospiral infection, primarily a history of reproductive disease and serological evidence of exposure to pathogenic leptospires (n=180) and aborted pig foetuses (n=24). Leptospire DNA was detected by the 'pathogenic' specific PCR in 25 tissues (14%) and the control beta-actin PCR was positive in all 204 samples confirming DNA was extracted from all samples. No leptospires were isolated from these samples by culture and no positives were detected with the 'saprophytic' PCR. In a subsidiary experiment, the 'pathogenic' PCR was used to analyse kidney samples from rodents (n=7) collected as part of vermin control in a zoo, with show animals with high microagglutination titres to Leptospira species, and five were positive. Fifteen PCR amplicons from 1 mouse, 2 rat and 14 pig kidney samples, were selected at random from positive PCRs (n=30) and sequenced. Sequence data indicated L. interrogans DNA in the pig and rat samples and L. inadai DNA, which is considered of intermediate pathogenicity, in the mouse sample. The only successful culture was from this mouse kidney and the isolate was confirmed to be L. inadai by classical serology. These data suggest this suite of PCRs is suitable for testing for the presence of pathogenic leptospires in pig herds where abortions and infertility occur and potentially in other animals such as rodents.

  2. Serología positiva a Leptospira interrogans, serovar cynopteri en caninos de la Ciudad de Buenos Aires, Argentina Cynopteri as a new serovar of Leptospira interrogansin canines of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    M.S Tealdo

    2007-12-01

    Full Text Available La Leptospirosis es una enfermedad infectocontagiosa, producida por una bacteria del género Leptospira, que ataca indistintamente al hombre y a animales domésticos y silvestres. El agente puede vivir y reproducirse en aguas de ríos, arroyos, lagos, aguas estancadas, etc. Es una patología polimorfa. Los caninos pueden actuar como fuente de infección para el hombre debido al estrecho contacto que se desarrolla entre ambos. Tradicionalmente al género Leptospira se lo considera integrado por dos especies: L. interrogans (formas patógenas y L. biflexa (abarca formas saprófitas. Estas especies a su vez, se dividen en serogrupos y serovares. Entre junio y septiembre de 2003 se recolectaron 110 muestras de suero de caninos que concurrieron al Instituto de Zoonosis Luis Pasteur (IZLP. Los sueros fueron procesados en los laboratorios de Diagnóstico de Leptospirosis del IZLP y del Instituto de Patobiología del INTA, Castelar (Provincia de Buenos Aires, con la técnica de microaglutinación en tubo (Técnica de Martín y Petit. Las muestras se enfrentaron a cepas de 23 serovares, resultando en una seroprevalencia del 33%. Un dato inédito fue el alto índice (59% de seropositividad (en su mayoría reaccionante a títulos 1/100 al serovar cynopteri. De los animales positivos (51% machos y 49% hembras, 30% provenían de barrios de zonas marginales y villas de emergencia y un 70% del resto de la ciudad. Un número de factores pudieron haber cambiado en los últimos años debido a la crisis económica (presencia de cartoneros, el uso de caballos para tracción en el ámbito de la ciudad y la cría clandestina de cerdos. Dado que estos valores muestran un incremento de la seroprevalencia respecto de los valores históricos para la ciudad y la detección del serovar cynopteri en un alto porcentaje de muestras, se recomienda considerar la inclusión de más serovares en los testeos serológicos en caninos.Leptospirosis is an infectious illness caused by

  3. Leptospira-rat-human relationship in Luzon, Philippines.

    Science.gov (United States)

    Villanueva, Sharon Yvette Angelina M; Saito, Mitsumasa; Baterna, Rubelia A; Estrada, Crystal Amiel M; Rivera, Ana Kriselda B; Dato, Micaella C; Zamora, Pia Regina Fatima C; Segawa, Takaya; Cavinta, Lolita L; Fukui, Takashi; Masuzawa, Toshiyuki; Yanagihara, Yasutake; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-11-01

    Leptospirosis is a zoonotic infection that is caused by the pathogenic species of Leptospira. Rats are the most important reservoirs of these organisms. Our study aimed to characterize Leptospira isolates from humans and rats and elucidate the Leptospira-rat-human relationship in Luzon, Philippines. Forty strains were isolated from humans and rats. The isolates were confirmed to be Leptospira and pathogenic through rrl- and flaB-PCR, respectively. Around 73% of the isolates were found to be lethal to hamsters. Serotyping showed that there were mainly three predominant leptospiral serogroups in the study areas namely Pyrogenes, Bataviae, and Grippotyphosa. Gyrase B gene sequence analysis showed that all the isolates belonged to Leptospira interrogans. Most had 100% similarity with serovar Manilae (15/40), serovar Losbanos (8/40), and serogroup Grippotyphosa (8/40). Strains from each group had highly identical pulsed-field gel electrophoresis patterns and were further grouped as A (Pyrogenes, 14), B (Bataviae, 8), and C (Grippotyphosa, 10). Results further revealed that similar serotypes were isolated from both humans and rats in the same areas. It is suggested that these three predominant groups with highly similar intra-group PFGE patterns may have been primarily transmitted by rats and persistently caused leptospirosis in humans particularly in the Luzon islands.

  4. Antibodies to Leptospira interrogans in goats and risk factors of the disease in Santa Catarina (West side), Brazil.

    Science.gov (United States)

    Topazio, Josué; Tonin, Alexandre A; Machado, Gustavo; Noll, Jessica C G; Ribeiro, André; Moura, Anderson B; Carmo, Guilherme M; Grosskopf, Hyolanda M; Martins, Jorge L R; Badke, Manoel R T; Stefani, Lenita M; Lopes, Leandro S; Da Silva, Aleksandro S

    2015-04-01

    Leptospirosis is an infectious disease caused by the bacterium Leptospira spp. In goats, the productive impact of leptospirosis is not well known and totally unknown in Santa Catarina (SC), Brazil. This study aimed to investigate leptospirosis seroprevalence and its risk factors in goats in the west side of SC. A total of 654 blood samples were analyzed using the microscopic agglutination technique and 35.47% (232) of the animals were seropositives. Except for serogroup Autumnalis, positive samples for all other serogroups were found as follows: Sejroe (Hardjo, Wolffi), Grippotyphosa (Grippotyphosa), Canicola (Canicola), Icterohaemorrhagiae (Icterohaemorrhagiae, Copenhageni), Australis (Australis, Bratislava) and Pomona (Pomona). The contact among sheep and goats, and the addition of concentrate as food supplement were found to be risk factors for leptospirosis. Based on these results, we conclude that there is a high occurrence of anti-Leptospira antibodies in goats in the Western part of Santa Catarina State.

  5. Immune response in hamsters immunised with a recombinant fragment of LigA from Leptospira interrogans, associated with carrier molecules

    Science.gov (United States)

    Oliveira, Thaís L; Bacelo, Kátia L; Schuch, Rodrigo A; Seixas, Fabiana K; Collares, Tiago; Rodrigues, Oscar ED; Vargas, Josimar; do Nascimento, Rafaella O; Dellagostin, Odir A; Hartwig, Daiane D

    2016-01-01

    Immunisation with the C-terminal region of leptospiral immunoglobulin-like A protein (LigANI) has shown promising results against leptospirosis. We evaluated the humoral immune response and protection induced by LigANI associated with carboxyl multi-walled carbon nanotubes (COOH-MWCNTs), CpG oligodeoxynucleotides (CpG ODNs), or Alhydrogel. Animals immunised with CpG ODNs were unable to develop a humoral immune response, whereas immunisation with LigANI and COOH-MWCNTs produced a high level of IgG antibodies, similar to that with LigANI and Alhydrogel, but it was not protective. The use of carbon nanotubes as an adjuvant in subunit vaccines against leptospirosis is a novel approach for improving specific IgG production. PMID:27759768

  6. Immune response in hamsters immunised with a recombinant fragment of LigA from Leptospira interrogans, associated with carrier molecules

    Directory of Open Access Journals (Sweden)

    Thaís L Oliveira

    Full Text Available Immunisation with the C-terminal region of leptospiral immunoglobulin-like A protein (LigANI has shown promising results against leptospirosis. We evaluated the humoral immune response and protection induced by LigANI associated with carboxyl multi-walled carbon nanotubes (COOH-MWCNTs, CpG oligodeoxynucleotides (CpG ODNs, or Alhydrogel. Animals immunised with CpG ODNs were unable to develop a humoral immune response, whereas immunisation with LigANI and COOH-MWCNTs produced a high level of IgG antibodies, similar to that with LigANI and Alhydrogel, but it was not protective. The use of carbon nanotubes as an adjuvant in subunit vaccines against leptospirosis is a novel approach for improving specific IgG production.

  7. PROTECTION AGAINST LEPTOSPIROSIS BY IMMUNIZATION WITH PLASMID DNA ENCODING 33 kDa ENDOFLAGELLIN OF L.INTERROGANS SEROVAR LAI

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective. To evaluate how the efficacy of DNA inocutation affects the ability to raise protective immunity against Leptospira.Methods. A pair of oligonucleotide primers were designed to amplify the endoflagellar gene of L. interrogans sensu stricto serovar lai. An approximately 840bp fragment was generated with PCR and inserted into VR1012, a plasmid DNA expression vector, after the fragment and VR1012 were digested respectively with EcoRV and Sal I. A recombinant plasmid designated as VR1012+flaB2 was obtained. The vector, VR1012 consits of a pUC18 backbone with the cytomegalovirus(CMV) IE1 enhancer, promoter, and intron A, transcription regulatory elements and the BGH polyadenylation sequences driving the expressing of leptospiral endoflagellar gene of L. interrogans sensu stricto serovar lai. Plasmid encoding leptospiral endoflagellin gene was injected into quadriceps of NZW rabbits.Results.This resulted in the generation of specific leptospiral antibody with high ELISA titer (1:32768) in the rabbits. Immuno/protection was performed in guinea pigs without adjuvant. The group"VR1012+flaB2" showed higher survival rate(90%,9/10 animals),compared with the group "VR1012 lack flaB2" and the group "normal saline".Conclusion.The technique of DNA vaccine has potential advantages over certain other vaccine preparation technologies. However whether DNA vaccine will be useful for vaccine development remains to be tested.

  8. Direct Detection and Differentiation of Pathogenic Leptospira Species Using a Multi-Gene Targeted Real Time PCR Approach

    Science.gov (United States)

    Ferreira, Ana Sofia; Costa, Pedro; Rocha, Teresa; Amaro, Ana; Vieira, Maria Luísa; Ahmed, Ahmed; Thompson, Gertrude; Hartskeerl, Rudy A.; Inácio, João

    2014-01-01

    Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpeteresenii and L. noguchii, which constitute the veterinary most relevant pathogenic species of Leptospira. The method uses sets of species-specific probes, and respective flanking primers, designed from ompL1 and secY gene sequences. To monitor the presence of inhibitors, a duplex amplification assay targeting both the mammal β-actin and the leptospiral lipL32 genes was implemented. The analytical sensitivity of all primer and probe sets was estimated to be <10 genome equivalents (GE) in the reaction mixture. Application of the amplification reactions on genomic DNA from a variety of pathogenic and non-pathogenic Leptospira strains and other non-related bacteria revealed a 100% analytical specificity. Additionally, pathogenic leptospires were successfully detected in five out of 29 tissue samples from animals (Mus spp., Rattus spp., Dolichotis patagonum and Sus domesticus). Two samples were infected with L. borgpetersenii, two with L. interrogans and one with L. kirschneri. The possibility to detect and identify these pathogenic agents to the species level in domestic and wildlife animals reinforces the diagnostic information and will enhance our understanding of the epidemiology of leptopirosis. PMID:25398140

  9. Direct detection and differentiation of pathogenic Leptospira species using a multi-gene targeted real time PCR approach.

    Directory of Open Access Journals (Sweden)

    Ana Sofia Ferreira

    Full Text Available Leptospirosis is a growing public and veterinary health concern caused by pathogenic species of Leptospira. Rapid and reliable laboratory tests for the direct detection of leptospiral infections in animals are in high demand not only to improve diagnosis but also for understanding the epidemiology of the disease. In this work we describe a novel and simple TaqMan-based multi-gene targeted real-time PCR approach able to detect and differentiate Leptospira interrogans, L. kirschneri, L. borgpeteresenii and L. noguchii, which constitute the veterinary most relevant pathogenic species of Leptospira. The method uses sets of species-specific probes, and respective flanking primers, designed from ompL1 and secY gene sequences. To monitor the presence of inhibitors, a duplex amplification assay targeting both the mammal β-actin and the leptospiral lipL32 genes was implemented. The analytical sensitivity of all primer and probe sets was estimated to be <10 genome equivalents (GE in the reaction mixture. Application of the amplification reactions on genomic DNA from a variety of pathogenic and non-pathogenic Leptospira strains and other non-related bacteria revealed a 100% analytical specificity. Additionally, pathogenic leptospires were successfully detected in five out of 29 tissue samples from animals (Mus spp., Rattus spp., Dolichotis patagonum and Sus domesticus. Two samples were infected with L. borgpetersenii, two with L. interrogans and one with L. kirschneri. The possibility to detect and identify these pathogenic agents to the species level in domestic and wildlife animals reinforces the diagnostic information and will enhance our understanding of the epidemiology of leptopirosis.

  10. MASTITE E SÍNDROME DA QUEDA DO LEITE / INFECÇÃO POR Leptospira interrogans EM OVELHAS DA RAÇA SANTA INÊS NO DISTRITO FEDERAL

    Directory of Open Access Journals (Sweden)

    Adriana Helena Rosa

    2012-06-01

    Full Text Available The aim of the present work was to determine the relationship between clinical mastitis and Leptospira interrogans / Milk Drop Syndrome in Santa Inês ewes. One thousand sheep were examined on 12 farms in the Distrito Federal, Brazil, as to their clinical condition, in order to identify animals with clinical mastitis. The animals were divided into two groups: animals which presented clinical mastitis symptoms (G1 and animals which did not have clinical mastitis symptoms (G2. Blood samples were collected from all ewes of the two groups. The microscopic agglutination test was performed in order to identify the seropositive animals to Leptospira spp. Four (4.08% animals of the first group were seropositives to Leptospira spp., of which three were positives to Hardjoprajitno (Norma and Hardjoprajitno (OMS sorovars and one to both Australis and Autumnalis sorovars. In the second group, two (5.26% animals were seropositives to both Hardjoprajitno (Norma and Hardjoprajitno (OMS sorovars. A relationship between Leptospira spp. infection / milk drop syndrome and the presence of clinical mastitis in ewes (p > 0.05 was not observed.

  11. Identificação da Leptospira interrogans sorovar pomona em camundongos geneticamente selecionados, para a alta e baixa produção de anticorpos, através da técnica de imunoperoxidase em tecido renal e isolamento bacteriano em meio de Fletcher Identification of Leptospira interrogans serovar pomona in mice genetically selected for high and low antibody production, by means of the immunoperoxidase technique in renal tissue and bacterial isolation in Fletcher medium

    Directory of Open Access Journals (Sweden)

    Maria Cristina Santos Haanwinckel

    2007-12-01

    Full Text Available O presente trabalho teve por objetivo identificar a presença da Leptospira interrogans sorovar pomona em camundongos geneticamente selecionados para a alta e baixa resposta a anticorpos. Todos os animais foram submetidos ao isolamento bacteriano, imunohistoquímica (imunoperoxidase em cortes de tecido renal e coloração através da hematoxilina-eosina. A técnica de imunoperoxidase apresentou-se pouco mais sensível em relação ao cultivo, entretanto, ambas foram bons parâmetros de identificação do agente. Presença de lesões renais mais intensas ocorreram em períodos em que houve maior número de bactérias isoladas em meio de cultivo. Camundongos da linhagem HIV-A conseguiram eliminar as leptospiras com maior eficiência e rapidez em relação as linhagem LIV-A, entretanto o estudo demonstrou que ambas linhagens da seleção IV-A foram eficientes em controlar o processo infeccioso.The present work had the objective of identifying the presence of Leptospira interrogans serovar pomona in mice that had been genetically selected for high and low response to antibodies. All the animals were subjected to bacterial isolation, immunohistochemical analysis (immunoperoxidase in renal tissue sections and hematoxylin-eosin staining. The immunoperoxidase technique was little more sensitive than culturing, but both were good parameters for agent identification. More severe renal lesions were present at times when there were greater numbers of bacteria isolated in culture medium. Mice of the lineage HIV-A were able to eliminate the Leptospira more efficiently and faster than the lineage LIV-A could. However, the study demonstrated that both lineages of the IV-A selection were efficient in controlling the infectious process.

  12. Serological prevalence of leptospiral infection in domestic animals in West Malaysia.

    Science.gov (United States)

    Bahaman, A R; Ibrahim, A L; Adam, H

    1987-10-01

    A cross-sectional serological survey of domestic animals in West Malaysia revealed that 25.5% of the animals examined had agglutinating antibodies to one or more antigens belonging to Leptospira interrogans. Significant prevalence of infection was observed in cattle (40.5%), buffaloes (31%) and pigs (16%). The Sejroe serogroup was shown to be the principal one involved in cattle and buffaloes, and to a lesser extent the Tarassovi and Pomona serogroups. Evidence of infection in domestic animals by strains bearing the other seven antigens appeared insignificant and was indicative of sporadic infection. A majority of the large (semi-intensive) cattle and buffalo farms demonstrated a high prevalence of leptospiral infection. In both species of domestic animals mentioned above, the prevalence of infection was significantly higher (P = 0.01) in the semi-intensive farms than in the smallholdings. Amongst cattle, the droughtmasters had the highest prevalence whilst the Kedah-Kelantan (an indigenous breed) had the lowest prevalence of leptospiral infection. In general, the temperate breeds of cattle had a significantly (P = 0.01) higher prevalence of infection than local breeds. Leptospiral infection in goats and sheep was shown to be sporadic, and the Pomona serogroup was the principal leptospiral serogroup involved in these small ruminants. The prevalence of infection in pigs was observed to decline during the study period, and it is suspected that pigs in West Malaysia are the maintenance host for serovar pomona whilst cattle are the maintenance host for serovar hardjo. Overall, it appears that domestic animals in Malaysia will play a bigger role in the epidemiology of leptospiral infection with the advent of sophisticated farming.

  13. Imunodiagnóstico da leptospirose humana através do teste ELISA-IgM, empregando-se diferentes preparações antigênicas a partir de sorotipos prevalentes de Leptospira interrogans Immunodiagnostic of human leptospirosis by ELISA-IgM, employing: different antigenic preparations as from prevalent serovars of Leptospira interrogans

    Directory of Open Access Journals (Sweden)

    Marcos Vinicius da Silva

    1990-08-01

    Full Text Available Realizou-se estudo comparativo de diferentes sorotipos de Leptospira interrogans utilizados na preparação de antígenos empregados no teste ELISA, para a detecção de anticorpos da classe IgM, em amostras de soro na fase precoce e tardia da leptospirose humana. Foram utilizados dez sorotipos, escolhidos entre os que apresentaram maior reatividade na soroaglutinação microscópica (SAM, na cidade de São Paulo. Os cinco sorotipos que apresentaram melhores resultados individualmente no teste ELISA-IgM (canicola, hebdomadis, icterohaemorrhagiae, cynopteri e brasiliensis, foram também estudados em mistura antigênica. Os antígenos não tratados apresentaram maior reatividade do que os antígenos tratados com Triton X - 100 (4% à temperatura de 50ºC, durante 4 horas. O teste ELISA-IgM empregando os sorotipos não tratados, isoladamente, e em mistura antigênica, mostrou-se altamente sensível, podendo ser empregado como teste de triagem para o diagnóstico precoce da leptospirose humana. Outra aplicação do teste é permitir a detecção do início de situações epidêmicas ou de surtos, possibilitando acionar medidas de vigilância epidemiológica.A comparative study among different serovars of Leptospira interrogans was performed in order to prepare antigens to detect IgM antibodies by ELISA in early and late phase of human leptospirosis. Ten serovars were chosen among the most prevalent detected by microscopic seroagglutination (SAM in São Paulo city. Using ELISA-IgM five of them showed better results (canicola, hebdomadis, icterohaemorrhagiae, cynopteri and brasiliensis. These ones were also studied in a pool. The non-treated antigens showed higher reactivity than the Triton X-100 (4%/50ºC/4h. ELISA-IgM using individually or pool of non treated antigens proved to be reliable with high sensitivity and should be used for an earlier diagnosis of leptospirosis, as a trial test. Faster diagnostic elucidation can be useful to detect

  14. Avaliação do potencial imunoprotetor de antígenos recombinantes de Leptospira interrogans

    OpenAIRE

    2009-01-01

    A leptospirose é uma doença causada por espiroquetas do gênero Leptospira. Ela é a zoonose mais difundida no mundo, sendo um problema de saúde pública e veterinária, principalmente em países em desenvolvimento. Na área de veterinária, a leptospirose é preocupante do ponto de vista clínico e econômico, devido ao risco à saúde pública, perdas reprodutivas e óbitos. A vacinação animal é amplamente realizada como medida de prevenção da enfermidade. Entretanto, a proteção conferi...

  15. Genotypic Analysis, Construction of the Expression System and Immunological Identification of the Recombinant Proteins of the LipL32 Gene in the Dominant Serogroups of Leptospira interrogans in China

    Institute of Scientific and Technical Information of China (English)

    范兴丽; 严杰; 毛亚飞; 李立伟; 李淑萍

    2004-01-01

    To investigate the existence of the major outer membrane pmtein (MOMP) gene Lip132 in 15 dominant Chineses trains of 15 semgroups of Leptospira iraerrogans and 2 intemational strains of 2 semgroups of Leptospira biflexa, and to clone and construct the expression system as well as to identify the recombinant pmteins, genomic DNAs from strains of leptospira were prepared by mutine phenol-chloroform method, and the fragments of the LipL32 gene with the whole length from the strains were amplified with high fidelity PCR. The target amplification products were, sequenced after T-A cloning, and the expression system for the genes were thereby constructed, Expression of the recombinant proteins was identified by using SDSPAGE after induction with IPTG at different dosages. Western blot assays with rabbit antiserum against the whole cell of TR/Patoc Ⅰ of Leptospira and immunized serum with rMOMPs were used to determine the immunoreactivity and immunogenicity of the recombinant proteins. Microscopic agglutination test was used to determine the cross- agglutination titres in rabbit sera immunized with rMOMPs, and the cell adherence model of Leptospira was used to examine the blocking effects of rabbit antisera against these rMOMPs. It was found that the LipL32 gene could be found in all the 17 strains of Leptospira mentioned above with two different genotypes, i.e.LipL32/1 and LipL32/2. Amounts of expressions of rMOMP1 and rMOMP2 after IPTG accounted for 40% and 10% of the total bacterial pmteins respectively. Both rMOMP1 and rMOMP2 could combine with the rab-bit antiserum against leptospiral TR/Patoc Ⅰ, and could induce the production of agglutination antibodies to these 17 strains of Leptospira with 1:2 to 1:64 MAT titres. The rabbit anti-rMOMP1 and anti-MOMP2 antibodies at 1:2 to 1 : 16 dilutions could efficiently block adherence of Leptospira. It concludes that all the Leptospira tested in the present study possess LipL32/1 or LipL32/2 genes, and the constructed

  16. The recombinant LIC10508 is a plasma fibronectin, plasminogen, fibrinogen and C4BP-binding protein of Leptospira interrogans.

    Science.gov (United States)

    Siqueira, Gabriela H; Teixeira, Aline F; Fernandes, Luis G; de Souza, Gisele O; Kirchgatter, Karin; Romero, Eliete C; Vasconcellos, Silvio A; Vieira, Monica L; Nascimento, Ana Lucia T O

    2016-03-01

    Leptospirosis is a zoonosis caused by pathogenic Leptospira spp. In this study, we report that the recombinant proteins LIC10507, LIC10508 and LIC10509 are recognized by confirmed leptospirosis serum samples at both phases of the disease. The recombinant rLIC10508 and rLIC10507 are plasminogen (PLG)-binding proteins, capable of generating plasmin in the presence of a PLG activator. The proteins bind to PLG in a dose-dependent and saturable manner, fulfilling host-ligand interaction. Furthermore, rLIC10508 interacts with fibrinogen (Fg), plasma fibronectin and C4b binding protein (C4BP). The binding of rLIC10508 to Fg decreases the fibrin clotting in a thrombin-catalyzed reaction. The incubation with 4 μM of protein promoted 40% inhibition upon clotting formation. C4BP bound to rLIC10508 retained its cofactor activity for factor I promoting the cleavage of C4b protein, which may reduce the membrane attack complex formation. Although these proteins have high amino acid sequence similarity, rLIC10508 is the most talented of the three, a behavior that might be explained by its unique putative 3D structure, whereas structures of rLIC10507 and rLIC10509 are very similar. Plasmin generation (rLIC10507 and rLIC10508), together with decreasing fibrin clot formation (rLIC10508) and impairment of the complement system (rLIC10508) may help the bacteria to overcome host defense, facilitating the infection process.

  17. Infecção experimental em suínos jovens com Leptospira interrogans sorovar wolffi: determinação de parâmetros bioquímicos Experimental infection by Leptospira interrogans serovar wolffi in young pigs: determination of biochemical parameters

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    José Carlos Rende

    2007-04-01

    Full Text Available Um estudo sobre infecção experimental foi realizado em oito suínos, com idade média de 90 dias, machos castrados, da raça Wessex, e distribuídos em dois grupos de quatro suínos cada. Durante 36 dias, foram analisadas as alterações bioquímicas nos soros dos suínos dos dois grupos. O Grupo I foi mantido como testemunho e recebeu 5,0mL de solução fisiológica estéril por via intravenosa (veia cava craniana e, no Grupo II, os suínos foram inoculados pela mesma via com 5,0mL de cultura de Leptospira interrogans sorovar wolffi , amostra L-10 selvagem isolada de tatu (Dasypus novemcinctus, contendo 1,0 x 10(8 leptospiras/mL. A partir do terceiro dia após a inoculação e em intervalos de 72 horas até o décimo oitavo dia, foram feitas coletas de sangue, sem anticoagulante, dos animais inoculados e testemunhas. Os parâmetros bioquímicos analisados foram: bilirrubina total, direta e indireta, ácidos graxos, glicose e proteínas plasmáticas. Foi detectado um aumento da bilirrubina direta no terceiro dia e um aumento no sexto dia da bilirrubina total e indireta após a inoculação. As dosagens de glicose, ácidos graxos e proteínas plasmáticas apresentaram uma diminuição a partir do terceiro dia da inoculação. Com os resultados obtidos, pode-se concluir que o aumento das taxas de bilirrubinas levam a uma definição de um diagnóstico de hemólise aguda, e que a hipoglicemia, a hipolipidemia e a hipoproteinemia podem estar relacionadas com lesões hepáticas e a uma septcemia.Todas as dosagens em todos os animais retornaram aos seus valores normais a partir do décimo quinto dia.Eight, 90 days old pigs, of the Wessex lineage all castrated male were used in experiment, divided into two groups of four animals. Biochemical alterations in the serum of the animals were analyzed in both groups during 36 days. Control (Group I received 5.0mL of a 0.9% sterile sodium chloride solution by intracranial vein injection; Group II animals

  18. Isolation and characterization of new Leptospira genotypes from patients in Mayotte (Indian Ocean.

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    Pascale Bourhy

    Full Text Available BACKGROUND: Leptospirosis has been implicated as a severe and fatal form of disease in Mayotte, a French-administrated territory located in the Comoros archipelago (southwestern Indian Ocean. To date, Leptospira isolates have never been isolated in this endemic region. METHODS AND FINDINGS: Leptospires were isolated from blood samples from 22 patients with febrile illness during a 17-month period after a PCR-based screening test was positive. Strains were typed using hyper-immune antisera raised against the major Leptospira serogroups: 20 of 22 clinical isolates were assigned to serogroup Mini; the other two strains belonged to serogroups Grippotyphosa and Pyrogenes, respectively. These isolates were further characterized using partial sequencing of 16S rRNA and ligB gene, Multi Locus VNTR Analysis (MLVA, and pulsed field gel electrophoresis (PFGE. Of the 22 isolates, 14 were L. borgpetersenii strains, 7 L. kirschneri strains, and 1, belonging to serogoup Pyrogenes, was L. interrogans. Results of the genotyping methods were consistent. MLVA defined five genotypes, whereas PFGE allowed the recognition of additional subgroups within the genotypes. PFGE fingerprint patterns of clinical strains did not match any of the patterns in the reference strains belonging to the same serogroup, suggesting that the strains were novel serovars. CONCLUSIONS: Preliminary PCR screening of blood specimen allowed a high isolation frequency of leptospires among patients with febrile illness. Typing of leptospiral isolates showed that causative agents of leptospirosis in Mayotte have unique molecular features.

  19. The Leptospiral Antigen Lp49 is a Two-Domain Protein with Putative Protein Binding Function

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Giuseppe,P.; Oliveira Neves, F.; Nascimento, A.; Gomes Guimaraes, B.

    2008-01-01

    Pathogenic Leptospira is the etiological agent of leptospirosis, a life-threatening disease that affects populations worldwide. Currently available vaccines have limited effectiveness and therapeutic interventions are complicated by the difficulty in making an early diagnosis of leptospirosis. The genome of Leptospira interrogans was recently sequenced and comparative genomic analysis contributed to the identification of surface antigens, potential candidates for development of new vaccines and serodiagnosis. Lp49 is a membrane-associated protein recognized by antibodies present in sera from early and convalescent phases of leptospirosis patients. Its crystal structure was determined by single-wavelength anomalous diffraction using selenomethionine-labelled crystals and refined at 2.0 Angstroms resolution. Lp49 is composed of two domains and belongs to the all-beta-proteins class. The N-terminal domain folds in an immunoglobulin-like beta-sandwich structure, whereas the C-terminal domain presents a seven-bladed beta-propeller fold. Structural analysis of Lp49 indicates putative protein-protein binding sites, suggesting a role in Leptospira-host interaction. This is the first crystal structure of a leptospiral antigen described to date.

  20. Genomic survey and expression analysis of DNA repair genes in the genus Leptospira.

    Science.gov (United States)

    Martins-Pinheiro, Marinalva; Schons-Fonseca, Luciane; da Silva, Josefa B; Domingos, Renan H; Momo, Leonardo Hiroyuki Santos; Simões, Ana Carolina Quirino; Ho, Paulo Lee; da Costa, Renata M A

    2016-04-01

    Leptospirosis is an emerging zoonosis with important economic and public health consequences and is caused by pathogenic leptospires. The genus Leptospira belongs to the order Spirochaetales and comprises saprophytic (L. biflexa), pathogenic (L. interrogans) and host-dependent (L. borgpetersenii) members. Here, we present an in silico search for DNA repair pathways in Leptospira spp. The relevance of such DNA repair pathways was assessed through the identification of mRNA levels of some genes during infection in animal model and after exposition to spleen cells. The search was performed by comparison of available Leptospira spp. genomes in public databases with known DNA repair-related genes. Leptospires exhibit some distinct and unexpected characteristics, for instance the existence of a redundant mechanism for repairing a chemically diverse spectrum of alkylated nucleobases, a new mutS-like gene and a new shorter version of uvrD. Leptospira spp. shares some characteristics from Gram-positive, as the presence of PcrA, two RecQ paralogs and two SSB proteins; the latter is considered a feature shared by naturally competent bacteria. We did not find a significant reduction in the number of DNA repair-related genes in both pathogenic and host-dependent species. Pathogenic leptospires were enriched for genes dedicated to base excision repair and non-homologous end joining. Their evolutionary history reveals a remarkable importance of lateral gene transfer events for the evolution of the genus. Up-regulation of specific DNA repair genes, including components of SOS regulon, during infection in animal model validates the critical role of DNA repair mechanisms for the complex interplay between host/pathogen.

  1. Influência da via de inoculação sobre o estabelecimento e a evolução da leptospirose em hamsters (Mesocricetus auratus experimentalmente infectados com Leptospira interrogans sorovar pomona

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    Nicodemos Alves de Macedo

    2004-06-01

    Full Text Available Foi investigada a influência da via de inoculação sobre o estabelecimento e a evolução da leptospirose em hamsters (Mesocricetus auratus experimentalmente infectados com Leptospira interrogans sorovar pomona. As vias de inoculação ensaiadas foram: intraperitoneal, subcutânea, oral, conjuntival e escarificação cutânea. O inóculo infeccioso foi constituído por uma cultura em meio de Fletcher, com 20 a 30 leptospiras por campo microscópio no aumento de 200 vezes. Os animais controle foram inoculados apenas com meio de Fletcher. Foram colhidas amostras de soro sanguíneo e fragmentos de rins na fase agônica da doença ou no 21º dia pós-infecção, quando todos os animais foram sacrificados. Para a pesquisa de leptospiras, foi feito o exame direto com microscopia óptica em campo escuro e cultivo em meio de Fletcher, pela técnica das diluições seriadas. A detecção de aglutininas anti-leptospiras foi realizada pela técnica de soroaglutinação microscópica. A instalação e evolução da leptospirose foram afetadas pela via de inoculação. A via oral foi a menos efetiva em estabelecer a infecção. Não foi observada associação estatística entre a freqüência de portadores e a via de inoculação.

  2. SOROPREVALÊNCIA DE ANTICORPOS ANTI-Neospora caninum E ANTI-Leptospira interrogans EM DUAS PROPRIEDADES DE VACAS LEITEIRAS COM RELATOS DE PREJUÍZOS REPRODUTIVOS NOMUNICÍPIO DE GOIANDIRA, GOIÁS

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    Rafael Quirino Moreira

    2010-06-01

    Full Text Available The aim of this study was to determine the seroprevalence ofantibodies anti-Neospora caninum and anti-Leptospira interrogansin dairy cows from Goiandira, Goiás State, Brazil. Serum samplesof 53 dairy cows from two herds were assayed for anti-N. caninumantibodies using an indirect immunofluorescent antibody test (IFATand microscopic-agglutination technique (MAT for L. interrogansagglutinins. Sera reacting at dilutions ≥ 1:50 and ≥ 1:100 wereconsidered positive for N. caninum and L. interrogans antibodiesrespectively. It was found that 35.9% (14 cows of the samplesfrom Farm 1 and 64.3% (9 cows from Farm 2 were positive forN. caninum. For L. interrogans, 87.2% (34 cows from Farm 1 and64.3% (9 cows from Farm 2 were positive. The serovars foundedwere: wolffi (21.74%; hardjo (18.11%; bratislava (14.49%;australis (12.32%; tarassovi (12.32%; icterohaemorrhagiae(7.25%; sentot (5.80%, grippotyphosa (5.07%; patoc (2.17%;cynoptero (0.72%. According to the results, it was possible toconclude that neosporosis and leptospirosis are endemic in dairycows and may also be a significant animal and human healthproblem in Goiandira, GO, Brazil.

  3. Comparative transcriptional and translational analysis of leptospiral outer membrane protein expression in response to temperature.

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    Miranda Lo

    Full Text Available BACKGROUND: Leptospirosis is a global zoonosis affecting millions of people annually. Transcriptional changes in response to temperature were previously investigated using microarrays to identify genes potentially expressed upon host entry. Past studies found that various leptospiral outer membrane proteins are differentially expressed at different temperatures. However, our microarray studies highlighted a divergence between protein abundance and transcript levels for some proteins. Given the abundance of post-transcriptional expression control mechanisms, this finding highlighted the importance of global protein analysis systems. METHODOLOGY/PRINCIPAL FINDINGS: To complement our previous transcription study, we evaluated differences in the proteins of the leptospiral outer membrane fraction in response to temperature upshift. Outer membrane protein-enriched fractions from Leptospira interrogans grown at 30 degrees C or overnight upshift to 37 degrees C were isolated and the relative abundance of each protein was determined by iTRAQ analysis coupled with two-dimensional liquid chromatography and tandem mass spectrometry (2-DLC/MS-MS. We identified 1026 proteins with 99% confidence; 27 and 66 were present at elevated and reduced abundance respectively. Protein abundance changes were compared with transcriptional differences determined from the microarray studies. While there was some correlation between the microarray and iTRAQ data, a subset of genes that showed no differential expression by microarray was found to encode temperature-regulated proteins. This set of genes is of particular interest as it is likely that regulation of their expression occurs post-transcriptionally, providing an opportunity to develop hypotheses about the molecular dynamics of the outer membrane of Leptospira in response to changing environments. CONCLUSIONS/SIGNIFICANCE: This is the first study to compare transcriptional and translational responses to temperature

  4. Evolutionary Implication of Outer Membrane Lipoprotein-Encoding Genes ompL1, lipL32 and lipL41 of Pathogenic Leptospira Species

    Institute of Scientific and Technical Information of China (English)

    K. Vedhagiri; K. Natarajaseenivasan; P. Chellapandi; S.G. Prabhalaran; Joseph Selvin; S. Sharma; P. Vijayachari

    2009-01-01

    Leptospirosis is recognized as the most widespread zoonosis with a global distribu-tion. In this study, the antigenic variation in Leptospira interrogans and Leptospira borgpetersenii isolated from human urine and field rat kidney was preliminarily confirmed by microscopic agglutination test using monoclonal antibodies, and was further subjected to amplification and identification of outer membrane lipopro-teins with structural gene variation. Sequence similarity analysis revealed that these protein sequences, namely OmpL1, LipL32 and LipL41, showed no more ho-mologies to outer membrane lipoproteins of non-pathogenic Leptospira and other closely related Spirochetes, but showed a strong identity within L. interrogans, suggesting intra-specific phylogenetic lineages that might be originated from a common pathogenic leptospiral origin. Moreover, the ompL1 gene showed more antigenic variation than lipL32 and lipL41 due to less conservation in secondary structural evolution within closely related species. Phylogenetically, ompL1 and lipL41 of these strains gave a considerable proximity to L. weilii and L. santaro-sai. The ompL1 gene of L. interrogans clustered distinctly from other pathogenic and non-pathogenic leptospiral species. The diversity of ompL genes has been an-alyzed and it envisaged that sequence-specific variations at antigenic determinant sites would result in slow evolutionary changes along with new serovar origina-tion within closely related species. Thus, a crucial work on effective recombinant vaccine development and engineered antibodies will hopefully meet to solve the therapeutic challenges.

  5. Doxycycline Attenuates Leptospira-Induced IL-1β by Suppressing NLRP3 Inflammasome Priming

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    Wenlong Zhang

    2017-07-01

    Full Text Available Doxycycline (Dox, a semisynthetic antibiotic, has been reported to exert multiple immunomodulatory effects. Treatment with Dox has a satisfactory curative effect against leptospirosis. In addition to its antibacterial action, we supposed that Dox also modulated immune response in controlling leptospira infection. Using J774A.1 mouse macrophages, the effects of Dox on protein and mRNA levels of IL-1β and TNF-α were investigated after infection with live or sonicated Leptospira interrogans serovar Lai strain Lai (56601. Specifically, the level of IL-1β but not TNF-α was sharply decreased when treated with Dox in leptospira-infected macrophages. Western blot analysis showed that Dox suppressed the activation of leptospira-induced MAPK and NF-κB signaling pathways. Using NLRP3-deficient and NLRC4-deficient mice, the data showed that the expression of leptospira-induced IL-1β was mainly dependent on the presence of NLRP3 inflammasome in macrophages. Meanwhile, Dox suppressed leptospira-induced NLRP3 inflammasome priming with the upregulation of the Na/K-ATPase Pump β1 subunit. The inhibition effect of Dox on IL-1β was also conspicuous in cells with lipopolysaccharide and ATP stimulation. These results were confirmed in vivo, as peritoneal fluids of mice and organs of hamsters expressed less IL-1β after treatment of leptospiral infection with Dox. Our results indicated that Dox also modulated immune response to attenuate leptospira-induced IL-1β by suppressing p38, JNK, p65, and NLRP3 inflammasome priming.

  6. Evaluation of loop-mediated isothermal amplification method (LAMP) for pathogenic Leptospira spp. detection with leptospires isolation and real-time PCR.

    Science.gov (United States)

    Suwancharoen, Duangjai; Sittiwicheanwong, Busara; Wiratsudakul, Anuwat

    2016-09-01

    Leptospirosis has been one of the worldwide zoonotic diseases caused by pathogenic Leptospira spp. Many molecular techniques have consecutively been developed to detect such pathogen including loop-mediated isothermal amplification method (LAMP). The objectives of this study were to evaluate the diagnostic accuracy of LAMP assay and real-time PCR using bacterial culture as the gold standard and to assess the agreement among these three tests using Cohen's kappa statistics. In total, 533 urine samples were collected from 266 beef and 267 dairy cattle reared in central region of Thailand. Sensitivity and specificity of LAMP were 96.8% (95% CI 81.5-99.8) and 97.0% (95% CI 94.9-98.2), respectively. The accuracy of LAMP (97.0%) was significantly higher than that of real-time PCR (91.9%) at 95% CI. With Cohen's kappa statistics, culture method and LAMP were substantially agreed with each other (77.4%), whereas real-time PCR only moderately agreed with culture (47.7%) and LAMP (45.3%), respectively. Consequently, LAMP was more effective than real-time PCR in detecting Leptospira spp. in the urine of cattle. Besides, LAMP had less cost and was simpler than real-time PCR. Thus, LAMP was an excellent alternative for routine surveillance of leptospirosis in cattle.

  7. Interaction of bovine peripheral blood polymorphonuclear cells and Leptospira species; innate responses in the natural bovine reservoir host.

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    Jennifer H Wilson-Welder

    2016-07-01

    Full Text Available Cattle are the reservoir hosts of Leptospira borgpetersenii serovar Hardjo, and can also be reservoir hosts of other Leptospira species such as L. kirschneri, and L. interrogans. As a reservoir host, cattle shed Leptospira, infecting other animals, including humans. Previous studies with human and murine neutrophils have shown activation of neutrophil extracellular trap or NET formation, and upregulation of inflammatory mediators by neutrophils in the presence of Leptospira. Humans, companion animals and most widely studied models of Leptospirosis are of acute infection, hallmarked by systemic inflammatory response, neutrophilia and septicemia. In contrast, cattle exhibit chronic infection with few outward clinical signs aside from reproductive failure. Taking into consideration that there is host species variation in innate immunity, especially in pathogen recognition and response, the interaction of bovine peripheral blood polymorphonuclear cells (PMNs and several Leptospira strains was evaluated. Studies including bovine-adapted strains, human pathogen strains, a saprophyte and inactivated organisms. Incubation of PMNs with Leptospira did induce slight activation of neutrophil NETs, greater than unstimulated cells but less than the quantity from E. coli P4 stimulated PMNs. Very low but significant from non-stimulated, levels of reactive oxygen peroxides were produced in the presence of all Leptospira strains and E. coli P4. Similarly, significant levels of reactive nitrogen intermediaries (NO2 was produced from PMNs when incubated with the Leptospira strains and greater quantities in the presence of E. coli P4. PMNs incubated with Leptospira induced RNA transcripts of IL-1β, MIP-1α, and TNF-α, with greater amounts induced by live organisms when compared to heat-inactivated leptospires. Transcript for inflammatory cytokine IL-8 was also induced, at similar levels regardless of Leptospira strain or viability. However, incubation of

  8. InvA protein is a Nudix hydrolase required for infection by pathogenic Leptospira in cell lines and animals.

    Science.gov (United States)

    Luo, Yihui; Liu, Yan; Sun, Dexter; Ojcius, David M; Zhao, Jinfang; Lin, Xuai; Wu, Dong; Zhang, Rongguang; Chen, Ming; Li, Lanjuan; Yan, Jie

    2011-10-21

    Leptospirosis caused by pathogenic species of the genus Leptospira is a re-emerging zoonotic disease, which affects a wide variety of host species and is transmitted by contaminated water. The genomes of several pathogenic Leptospira species contain a gene named invA, which contains a Nudix domain. However, the function of this gene has never been characterized. Here, we demonstrated that the invA gene was highly conserved in protein sequence and present in all tested pathogenic Leptospira species. The recombinant InvA protein of pathogenic L. interrogans strain Lai hydrolyzed several specific dinucleoside oligophosphate substrates, reflecting the enzymatic activity of Nudix in Leptospira species. Pathogenic leptospires did not express this protein in media but temporarily expressed it at early stages (within 60 min) of infection of macrophages and nephric epithelial cells. Comparing with the wild type, the invA-deficient mutant displayed much lower infectivity and a significantly reduced survival rate in macrophages and nephric epithelial cells. Moreover, the invA-deficient leptospires presented an attenuated virulence in hamsters, caused mild histopathological damage, and were transmitted in lower numbers in the urine, compared with the wild-type strain. The invA revertant, made by complementing the invA-deficient mutant with the invA gene, reacquired virulence similar to the wild type in vitro and in vivo. The LD(50) in hamsters was 1000-fold higher for the invA-deficient mutant than for the invA revertant and wild type. These results demonstrate that the InvA protein is a Nudix hydrolase, and the invA gene is essential for virulence in pathogenic Leptospira species.

  9. Prevalence of Leptospira spp. in urban rodents from a groceries trade center of Medellin, Colombia.

    Science.gov (United States)

    Agudelo-Flórez, Piedad; Londoño, Andrés F; Quiroz, Víctor H; Angel, Juan C; Moreno, Natalí; Loaiza, Erica T; Muñoz, Luis F; Rodas, Juan D

    2009-11-01

    Leptospirosis is a widely distributed zoonosis, and rats are its most common source of infection. Our goal was to determine the frequency for Leptospira infection in rodents in a farmers market in the city of Medellin. We performed a descriptive transversal study sampling 254 rodents. Rodents were bled and killed, and kidneys samples were taken. Supernatants of macerated kidneys were cultured on Fletcher medium. Microagglutination tests (MATs) with 11 serovars were also carried out in rat serum, and a polymerase chain reaction (PCR) specific for pathogenic species was used to test each bacterial culture. All animals were identified as Rattus norvegicus; 25% and 20% were positive by MAT and culture, respectively. PCR tests of 12 isolates were positive for pathogenic serovars, and 4 of them were confirmed as L. interrogans by sequencing. These data show the role of this natural carrier and shedder of pathogenic leptospires in the epidemiology of urban leptospirosis in Colombia.

  10. 绵阳市1963~1997年钩端螺旋体病疫情及流行菌株变化分析%THE CHANGE OF LEPTOSPIROSIS AND THO STRAIN OF LEPTOSPIRA INTERROGANS IN MLANYANG IN 1963~1997

    Institute of Scientific and Technical Information of China (English)

    刘汉军; 刘昌弟; 周荣

    2000-01-01

    The article analyzed the change of Leptospirosis and strain of Leptospira interrogans in Mianyang in 1963-1997. The annual average incidencd rate is 4. 73 and the mortality rate is 0. 079 per one hundred thousand persons. In this area,the distribution of Leptospirosis agreed on others internal reports in sex ,age,profession and seasonlity. 5 outbreaks have been taken place in 35 years. Four of which were major Icterohaemorrhagiae serogroup Icterohaemorrhagiae sertoype and one was Hebdomadis Serogroup Hebdomadis Serotype. Leptospira 7 Serogroup and 10serotype have been found in 49 Leptospira interrogans which have been cultivated from blood of patients. It supports that rodent is the principal infections source of Leptospirosis that 174 Leptospira interrogans have been isolated from rodent.%本文报告了四川绵阳市35年钩端螺旋体病(下称钩体)疫情及流行菌株情况,年平均发病率4.73/10万,年平均死亡率0.079/10万,钩体病的性别、年龄、职业及季节分布与国内报道相一致。35年中发生5次局部暴发流行,4次以黄疽出血型为主,一次以七日热型为主。从病人血分离到49株钩体菌,分属七群10个血清型,从动物体内分离到菌株174株,证实啮齿类动物为主要传染源。

  11. Isolation of Leptospira from blood culture bottles.

    Science.gov (United States)

    Girault, Dominique; Soupé-Gilbert, Marie-Estelle; Geroult, Sophie; Colot, Julien; Goarant, Cyrille

    2017-01-31

    With the increasing use of real-time PCR techniques, Leptospira isolation has mostly been abandoned for the diagnosis of human leptospirosis. However, there is a great value of collecting Leptospira isolates to better understand the epidemiology of this complex zoonosis and to provide the researchers with different isolates. In this study, we have successfully isolated different Leptospira strains from BacT/Alert aerobic blood culture bottles and suggest that this privileged biological material offers an opportunity to isolate leptospires.

  12. THE CONSTRUCTION AND EXPRESSION OF RECOMBINANT SHUTTLE PLASMID WITH OMPL1 GENE FROM LEPTOSPIRA INTERROGANS SEROVAR LAI STRAIN 017 IN BACILLE CALMETTE GUERIN

    Institute of Scientific and Technical Information of China (English)

    鲍朗; 邱洪宇; 晏菊芳; 谢勇恩; 陈玮

    2002-01-01

    Objective.To construct recombinant BCG against leptospirosis.Methods.We amplified the entire open reading frame of the OmpL1 gene from the genome of the leptospire serovar Lai strain 017.Two recombinant plasmids pBQ1 and pBQ2 were constructed by oriented ligation based on the E.coli BCG shuttle plasmids pMV261 and pMV361 respectively.The recombinant plasmids were transformed into BCG by electroporation.The rBCGs bearing pBQ1 and pBQ2 were induced by high temperature of 45℃ .Results.The expressed product,a 35kD protein was detected by SDS PAGE.The result indicates that pBQ1 and pBQ2 can express OmpL1 in rBCG.Conclusion.The technical methods in this study may help detect the immunogenicity and immunoprotection of OmpL1 and develop more safe,highly effective rBCG bearing leptospiral antigen with long lasting protection.

  13. Epidemiological patterns of Leptospira spp. among slaughterhouse workers in Zanjan- Iran

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    Nahid Soltani Majd

    2012-10-01

    Full Text Available Objective: To determine epidemiological patterns of Leptospira spp. among slaughterhouse workers in Zanjan- Iran during 201 1. Methods: 98 human blood samples collected from slaughterhouse workers in Zanjan province, in 2011. The serum samples were analyzed with the microagglutination test (MAT in order to detect antibodies against Leptospira interrogans. Results: The results of this study showed that from 98 Samples, 34 Samples (34.7% were positive to different leptospiral sreovars. The lowest dilution that each serum was considered positive was 1:200. The most prevalent Leptospira serovars was Hardjo (47.8%, Grippotyphosa(15.2%, and the lowest belonged to serovar Sejro(4.3%. Conclusions: Leptospirosis is a work-related disease and slaughterhouses ’ workers face a higher risk than other individuals in danger of contracting it which, in turn, leads to transmittance of the infection into the food and protein cycle. Early diagnosis of the disease could prevent its occurrences in these groups of workers.

  14. Glicolipoproteína de Leptospira interrogans sorogrupo icterohaemorrhagiae: distribuição em fígado e rim de cobaias experimentalmente infectadas

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    R.T. Macêdo Santos

    1989-08-01

    Full Text Available Acredita-se que as lesões teciduais na leptospirose possam decorrer da ação direta das leptospiras, de toxinas sintetizadas ou liberadas durante sua lise. O presente estudo visou a extração quimica da glicolipoproteína (GLP da leptospira, a produção de anti-soro anti-GLP e a avaliação de sua distribuição em cortes de fígado e rim de cobaias inoculadas e sacrificadas em estudo seqüencial diário até o 6°dia de infecção, correspondente ao pico da doença. Procurou-se também correlacionar a expressão tecidual da GLP com o grau de lesões locais, em busca de novos subsídios para a compreensão da patogenia da leptospirose. A QLP foi detectada em fígado e rim de 2 dentre 6 cobaias no 5°dia e em todas as 6 no 6° dia de infecção, sob a forma de grânulos no citoplasma de macrófagos, livres no interstício ou acolados à membrana de células endoteliais e parenquimatosas, especialmente nas regiões mais lesadas. A cronologia do aparecimento da GLP e sua distribuição sugerem tratar-se de produto dc lise de leptospiras fagocitadas por macrófagos e que esta substância, conquanto não comprovada como iniciadora das lesões, associa-se a seu agravamento nas etapas mais avançadas da leptospirose.

  15. Resposta humoral, recuperação bacteriana e lesões histológicas em camundongos geneticamente selecionados para bons e maus produtores de anticorpos e Balb/c, frente à infecção por Leptospira interrogans sorovar icterohaemorrhagiae Humoral immune response, bacterial recovery and time lesions in mice geneticaly selected for high and low antibody production and in outbreed Balb/c mice face to Leptospira interrogans sorovar icterohaemorrhagiae

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    Márcia Marinho

    2003-01-01

    Full Text Available O presente trabalho teve por finalidade associar a cinética da resposta humoral à recuperação de leptospiras viáveis e à intensidade das lesões teciduais em camundongos geneticamente selecionados para bons (High e maus (Low produtores de anticorpos (seleção IV-A, além de camundongos outbreed, Balb/c, inoculados com amostra patogênica de Leptospira interrogans sorovar icterohaemorrhagiae. As linhagens High e Low (seleção IV-A apresentam modificações em alguns compartimentos da resposta imune, principalmente em relação à atividade macrofágica, representando fenótipos extremos encontrados em populações naturais heterogêneas. Os camundongos foram sacrificados em oito momentos após a infecção. A análise dos resultados revelou que a partir do 7º dia após a infecção, os camundongos da linhagem High apresentaram elevação nos títulos de anticorpos estatisticamente significantes quando comparados aos camundongos da linhagem Low, mantendo assim o efeito multiespecífico. Os camundongos Balb/c apresentaram resultados intermediários entre as duas linhagens. A produção de anticorpos colaborou como fator limitante à infecção, pois quando obteve-se maior recuperação de leptospiras, na fase inicial da infecção, os títulos de anticorpos encontravam-se em elevação. As lesões observadas nos órgãos de camundongos infectados consistiram basicamente nos mesmos processos inflamatórios e degenerativos, que não se alteraram, variando apenas o grau de comprometimento tecidual, de acordo com a linhagem. A linhagem high apresentou lesões mais extensas que as apresentadas pelas linhagens low e Balb/c, sendo que nesta última as lesões foram moderadas. De forma geral a linhagem High e Balb/c apresentaram um perfil de resposta Th2, com o maior índice de produção de anticorpos e gravidade das lesões, enquanto a linhagem Low apresentou um perfil de resposta Th1.The aim of the present work was to evaluate the association

  16. Complement Evasion by Pathogenic Leptospira.

    Science.gov (United States)

    Fraga, Tatiana Rodrigues; Isaac, Lourdes; Barbosa, Angela Silva

    2016-01-01

    Leptospirosis is a neglected infectious disease caused by spirochetes from the genus Leptospira. Pathogenic microorganisms, notably those which reach the blood circulation such as Leptospira, have evolved multiple strategies to escape the host complement system, which is important for innate and acquired immunity. Leptospira avoid complement-mediated killing through: (i) recruitment of host complement regulators; (ii) acquisition of host proteases that cleave complement proteins on the bacterial surface; and, (iii) secretion of proteases that inactivate complement proteins in the Leptospira surroundings. The recruitment of host soluble complement regulatory proteins includes the acquisition of Factor H (FH) and FH-like-1 (alternative pathway), C4b-binding protein (C4BP) (classical and lectin pathways), and vitronectin (Vn) (terminal pathway). Once bound to the leptospiral surface, FH and C4BP retain cofactor activity of Factor I in the cleavage of C3b and C4b, respectively. Vn acquisition by leptospires may result in terminal pathway inhibition by blocking C9 polymerization. The second evasion mechanism lies in plasminogen (PLG) binding to the leptospiral surface. In the presence of host activators, PLG is converted to enzymatically active plasmin, which is able to degrade C3b, C4b, and C5 at the surface of the pathogen. A third strategy used by leptospires to escape from complement system is the active secretion of proteases. Pathogenic, but not saprophytic leptospires, are able to secrete metalloproteases that cleave C3 (central complement molecule), Factor B (alternative pathway), and C4 and C2 (classical and lectin pathways). The purpose of this review is to fully explore these complement evasion mechanisms, which act together to favor Leptospira survival and multiplication in the host.

  17. Comparison between generalized linear modelling and additive Bayesian network; identification of factors associated with the incidence of antibodies against Leptospira interrogans sv Pomona in meat workers in New Zealand.

    Science.gov (United States)

    Pittavino, M; Dreyfus, A; Heuer, C; Benschop, J; Wilson, P; Collins-Emerson, J; Torgerson, P R; Furrer, R

    2017-09-01

    Additive Bayesian Network (ABN) is a graphical model which extends Generalized Linear Modelling (GLM) to multiple dependent variables. The present study compares results from GLM with those from ABN analysis used to identify factors associated with Leptospira interrogans sv Pomona (Pomona) infection by exploring the advantages and disadvantages of these two methodologies, to corroborate inferences informing health and safety measures at abattoirs in New Zealand (NZ). In a cohort study in four sheep slaughtering abattoirs in NZ, sera were collected twice a year from 384 meat workers and tested by Microscopic Agglutination with a 91% sensitivity and 94% specificity for Pomona. The study primarily addressed the effect of work position, personal protective equipment (PPE) and non-work related exposures such as hunting on a new infection with Pomona. Significantly associated with Pomona were "Work position" and two "Abattoirs" (GLM), and "Work position" (ABN). The odds of Pomona infection (OR, [95% CI]) was highest at stunning and hide removal (ABN 41.0, [6.9-1044.2]; GLM 57.0, [6.9-473.3]), followed by removal of intestines, bladder, and kidneys (ABN 30.7, [4.9-788.4]; GLM 33.8, [4.2-271.1]). Wearing a facemask, glasses or gloves (PPE) did not result as a protective factor in GLM or ABN. The odds of Pomona infection was highest at stunning and hide removal. PPE did not show any indication of being protective in GLM or ABN. In ABN all relationships between variables are modelled; hence it has an advantage over GLM due to its capacity to capture the natural complexity of data more effectively. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Comparison of three diagnostic techniques for the detection of leptospires in the kidneys of wild house mice (Mus musculus Comparação de três métodos de diagnóstico para detecção de leptospiras em rins de camundongos selvagens (Mus musculus

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    Carlos A. Rossetti

    2004-03-01

    Full Text Available Forty-one wild house mice (Mus musculus were trapped in an urban area, near railways, in Santa Fe city, Argentina. Both kidneys from each mouse were removed for bacteriological and histological examination. One kidney was inoculated into Fletcher semi-solid medium and isolates were serologically typed. The other kidney was microscopically examined after hematoxylin-eosin, silver impregnation and immunohistochemical stains. Leptospires, all of them belonging to the Ballum serogroup, were isolated from 16 (39% out of 41 samples. The presence of the agent was recorded in 18 (44% and in 19 (46% out of 41 silver impregnated and immunohistochemically stained samples respectively. Additionally, leptospires were detected in high number on the apical surface of epithelial cells and in the lumen of medullary tubules and they were less frequently seen on the apical surface of epithelial cells or in the lumen of the cortical tubules, which represents an unusual finding in carrier animals. Microscopic lesions consisting of focal mononuclear interstitial nephritis, glomerular shrinkage and desquamation of tubular epithelial cells were observed in 13 of 19 infected and in 10 of 22 non-infected mice; differences in presence of lesions between infected and non-infected animals were not statistically significant (P=0,14. The three techniques, culture, silver impregnation and immunohistochemistry, had a high agreement (k³0.85 and no significant differences between them were detected (P>0.05. In addition, an unusual location of leptospires in kidneys of carrier animals was reported, but a relationship between lesions and presence of leptospires could not be established.Foram capturados 41 camundongos (Mus musculus na região urbana, próximo à ferrovia da cidade de Santa Fé, Argentina. Os rins de cada animal capturado foram removidos para estudos bacteriológicos e histológicos. Um dos rins foi imerso em meio semi-sólido de Fletcher para isolamento de

  19. Primer reporte en Cuba de Leptospira interrogans serovar Tarassovi y caracterización clínica epizootiologica en focos de Leptospirosis porcina

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    Dra. Dania Feraud Tercilla;

    2005-04-01

    Full Text Available La leptospirosis es una enfermedad zoonótica de focalidad natural que teniendo en cuenta el tipo de explotación, manejo, medidas protectivas y vigilancia epidemiológica podemos controlarla. De ahí que el objetivo de nuestro trabajo halla sido el determinar las características clínico-epizootiologicas en focos activos de leptospirosis en cerdos e identificar los serovares presentes a través del aislamiento. Para lograrlo nos propusimos dos experimentos, uno relacionado con la caracterización epizoótica de dos focos de leptospirosis porcina, en los que se presentaron índices de aborto de 5 y 6 % respectivamente. El otro experimento abordó el aislamiento e identificación de cepas de leptospira encontrada en los focos, la caracterización general de las unidades, investigación serológica relacionada con la enfermedad y diagnostico diferencial fueron actividades contempladas en el experimento, así como las descripciones de aislamiento y circulación del serovar Tarassovi por primera vez en Cuba en animales autóctonos, esto ocurrió sin grandes alteraciones de los indicadores productivos y reproductivos.Leptospirosis is a zoonotic disease occurring in natural foci, and could be controlled, taking into consideration: type of exploitation, protective measures and epidemiologic surveillance. The objective of this work is to determine the clinical and epidemiological characteristics of swine leptospirosis in disease active foci, and identify the serological varieties by means of isolation. Two experiments were developed, one related with the epidemiological characterization of swine leptospirosis foci, in which abortion occurred on 5 and 6% respectively; the second experiment was about the isolation and identification of Leptospira strains from the foci, general characterization of the piggeries: serological research related with the disease and its differential diagnosis, were activities within this experiment. Descriptions of isolation

  20. Leptospira Infection Interferes with the Prothrombinase Complex Assembly during Experimental Leptospirosis

    Science.gov (United States)

    Vieira, Monica L.; de Andrade, Sonia A.; Morais, Zenaide M.; Vasconcellos, Silvio A.; Dagli, Maria Lucia Z.; Nascimento, Ana Lucia T. O.

    2017-01-01

    Leptospirosis is a worldwide zoonotic and neglected infectious disease of human and veterinary concern, caused by pathogenic Leptospira species. Although bleeding is a common symptom of severe leptospirosis, the cause of hemorrhage is not completely understood. In severe infections, modulation of hemostasis by pathogens is an important virulence mechanism, and hemostatic impairments such as coagulation/fibrinolysis dysfunction are frequently observed. Here, we analyze the coagulation status of experimentally infected hamsters in an attempt to determine coagulation interferences and the origin of leptospirosis hemorrhagic symptomatology. Hamsters were experimentally infected with L. interrogans. The lungs, kidneys, and livers were collected for culture, histopathology, and coagulation assays. L. interrogans infection disturbs normal coagulation in the organs of animals. Our results suggest the presence of a thrombin-like factor or FX activator, which is able to activate FII in the leptospirosis organ extracts. The activity of those factors is accelerated in the prothrombinase complex. Additionally, we show for the first time that live leptospires act as a surface for the prothrombinase complex assembly. Our results contribute to the understanding of leptospirosis pathophysiological mechanisms and may open new routes for the discovery of novel treatments in the severe manifestations of the disease. PMID:28400758

  1. Detection of reactive canines to Leptospira in Campeche City, Mexico.

    Science.gov (United States)

    Blum Domínguez, Selene Del C; Chi Dzib, María Y; Maldonado Velázquez, María G; Nuñez Oreza, Luis A; Gómez Solano, Mónica I; Caballero Poot, Rebeca I; Tamay Segovia, Paulino

    2013-01-01

    Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. The survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. Nine Leptospira interrogans serovars were tested by the microagglutination test. Reactivity was 21.3 % (69/323), 17.2 % corresponded to household dogs and 26.7 % to stray dogs. Leptospira Canicola (29 %), Leptospira Hardjo (22.58 %), and Leptospira Icterohaemorrhagiae (16.12 %) were the most common serovars reacting against the serum of household animals, while Leptospira Canicola (15.78 %), Leptospira icterohaemorrhagiae (13.15 %), and Leptospira Pomona (7.89 %) were those reacting in stray dogs. Results showed that all dogs have been in contact with different Leptospira serovars and outdoor exposure is the main infection risk factor.

  2. Perfil dos cães sororreagentes para aglutininas anti-Leptospira interrogans em Belo Horizonte, Minas Gerais, 2001/2002 Serological profile of seropositive dogs to anti-Leptospira interrogans agglutinins in Belo Horizonte, Minas Gerais, Brazil, 2001-2002

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    D.F. Magalhães

    2007-10-01

    Full Text Available The serological profile of seropositive dogs according to anti-Leptospira agglutinins was checked in Belo Horizonte including variables such as race, sex, age and whether the dog had an owner or not. The dogs were captured by the Zoonosis Control Center in nine neighborhoods around the city and were separated in two categories - with owners or captured on the streets. The prevalence of anti-Leptospira agglutinins was evaluated in 3,417 blood samples using the microscopic agglutination test (MAT from September 2001 to September 2002. It was found that 13.1% of the dogs had seropositive results with the most reactive serovars being Canicola (7.0%, Ballum (6.1%, Pyrogenes (3.2% and Icterohaemorrhagiae (2.9%. The prevalence of other serovars was less than 1.0%. Greater prevalence was found in male, crossbred dogs, without owners. There were no significant results due to age in 95% (P=0.808 of the cases. According to the results, more research should be done in order to isolate and classify the serovars in positive dogs, especially Ballum and Pyrogenes, which will suggest their inclusion in the commercial vaccines against leptospira used in dogs in this city.

  3. Seroprevalence of bovine leptospiral antibodies by microscopic agglutination test in Southeast of Iran

    Institute of Scientific and Technical Information of China (English)

    Mohammad Khalili; Ehsanollah Sakhaee; Mohammad Reza Aflatoonian; Gholamreza Abdollahpour; Saeed Sattari Tabrizi; Elham Mohammadi Damaneh; Sajad Hossini-nasab

    2014-01-01

    Objective:To evaluate serological findings of bovine leptospirosis which is a zoonotic disease with worldwide distribution caused by Leptospira interrogans. Methods: One hundred and sixty seven sera were collected from 9 commercial dairy herds in jiroft suburbs, from July to October 2011. Microscopic agglutination test (MAT) was used to evaluates serological findings of bovine leptospirosis in Jiroft suburb dairy farms, Kerman province, Iran. Results:Antibodies were found by MAT at least against one serovar of Leptospira interrogans in 29 samples (17.36%) among 167 sera at a dilution 1:100 or higher, and Leptospira pomona was the most prevalent serovar. Positive titers against more than one serovar were detected in 6 sera of the positive samples. Conclusion:This study is the first report of leptospirosis in Southeast Iran and showed that Leptospira pomona was the most and Leptospira icterohaemorrhagiae the least prevalent serovars in Southeast Iran.

  4. Highly Sensitive Loop-Mediated Isothermal Amplification for the Detection of Leptospira

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    Hua-Wei Chen

    2015-01-01

    Full Text Available Leptospirosis is a worldwide zoonosis caused by an infection with the pathogenic species of Leptospira. We have developed a loop-mediated isothermal amplification (LAMP assay to detect the DNA of Leptospira spp. Six sets of primers targeting the gene of the subsurface protein, lipL32, were evaluated for their detection sensitivity. The best primer set detected less than 25 copies of lipL32 per reaction of both plasmid DNA template and purified leptospiral genomic DNA. By combining primers targeting lipL32 with the previously published primer set targeting lipL41, the sensitivity of the assay was improved to 12 copies of L. interrogans. The specificity of the LAMP assay was evaluated by using the genomic DNA from other clinically encountered bacterial species such as different strains of Orientia tsutsugamushi, Rickettsia typhi, Rickettsia conorii, Rickettsia rickettsii, Coxiella burnetii, and Bartonella bacilliformis. These genomic DNA samples were all negative in our LAMP assay. The sensitivity of the LAMP assay was very similar to that of quantitative real time PCR. Several detection methods for the amplified product of LAMP assay were performed to demonstrate the simplicity of the assay. In summary, our results have suggested that this assay is rapid, robust, and easy to perform and has the potential to be used in endemic locations.

  5. Genomics, proteomics, and genetics of leptospira.

    Science.gov (United States)

    Picardeau, Mathieu

    2015-01-01

    Recent advances in molecular genetics, such as the ability to construct defined mutants, have allowed the study of virulence factors and more generally the biology in Leptospira. However, pathogenic leptospires remain much less easily transformable than the saprophyte L. biflexa and further development and improvement of genetic tools are required. Here, we review tools that have been used to genetically manipulate Leptospira. We also describe the major advances achieved in both genomics and postgenomics technologies, including transcriptomics and proteomics.

  6. Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires

    Science.gov (United States)

    Millán, Javier; García, Emilio J; Oleaga, Álvaro; López-Bao, José Vicente; Llaneza, Luis; Palacios, Vicente; Candela, Mónica G; Cevidanes, Aitor; Rodríguez, Alejandro; León-Vizcaíno, Luis

    2014-01-01

    The Iberian wolf (Canis lupus) is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33%) showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques). Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens. PMID:25494467

  7. Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires

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    Javier Millán

    2014-12-01

    Full Text Available The Iberian wolf (Canis lupus is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33% showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques. Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4, Icterohaemorrhagiae (n = 3 and Sejroë, Ballum and Grippotyphosa (n = 1 each, indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens.

  8. Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires.

    Science.gov (United States)

    Millán, Javier; García, Emilio J; Oleaga, Álvaro; López-Bao, José Vicente; Llaneza, Luis; Palacios, Vicente; Candela, Mónica G; Cevidanes, Aitor; Rodríguez, Alejandro; León-Vizcaíno, Luis

    2014-12-01

    The Iberian wolf (Canis lupus) is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33%) showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques). Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens.

  9. A simple technique for long-term preservation of leptospires.

    Science.gov (United States)

    Samir, Ahmed; Wasfy, Momtaz O

    2013-03-01

    The viability of six serovars of Leptospira spp. was studied after long storage at -70°C. The bacteria were either preserved in Ellinghausen-McCullough-Johnson-Harris (EMJH) liquid growth medium or in sheep blood added as a cryoprotectant. The viability of the strains was observed on a monthly basis by dark-ground microscopy over a period of 20 months at -70°C. Addition of sheep blood was not significantly advantageous, since leptospires that were stored in EMJH showed a slight increase in number after recovery. The results suggest a very simple and useful technique for long-term preservation of such Leptospira.

  10. Bioinformatics describes novel Loci for high resolution discrimination of leptospira isolates.

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    Gustavo M Cerqueira

    Full Text Available BACKGROUND: Leptospirosis is one of the most widespread zoonoses in the world and with over 260 pathogenic serovars there is an urgent need for a molecular system of classification. The development of multilocus sequence typing (MLST schemes for Leptospira spp. is addressing this issue. The aim of this study was to identify loci with potential to enhance Leptospira strain discrimination by sequencing-based methods. METHODOLOGY AND PRINCIPAL FINDINGS: We used bioinformatics to evaluate pre-existing loci with the potential to increase the discrimination of outbreak strains. Previously deposited sequence data were evaluated by phylogenetic analyses using either single or concatenated sequences. We identified and evaluated the applicability of the ligB, secY, rpoB and lipL41 loci, individually and in combination, to discriminate between 38 pathogenic Leptospira strains and to cluster them according to the species they belonged to. Pairwise identity among the loci ranged from 82.0-92.0%, while interspecies identity was 97.7-98.5%. Using the ligB-secY-rpoB-lipL41 superlocus it was possible to discriminate 34/38 strains, which belong to six pathogenic Leptospira species. In addition, the sequences were concatenated with the superloci from 16 sequence types from a previous MLST scheme employed to study the association of a leptospiral clone with an outbreak of human leptospirosis in Thailand. Their use enhanced the discriminative power of the existing scheme. The lipL41 and rpoB loci raised the resolution from 81.0-100%, but the enhanced scheme still remains limited to the L. interrogans and L. kirschneri species. CONCLUSIONS: As the first aim of our study, the ligB-secY-rpoB-lipL41 superlocus demonstrated a satisfactory level of discrimination among the strains evaluated. Second, the inclusion of the rpoB and lipL41 loci to a MLST scheme provided high resolution for discrimination of strains within L. interrogans and L. kirschneri and might be useful

  11. Leptospira and Inflammation

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    C. F. Gonçalves-de-Albuquerque

    2012-01-01

    Full Text Available Leptospirosis is an important zoonosis and has a worldwide impact on public health. This paper will discuss both the role of immunogenic and pathogenic molecules during leptospirosis infection and possible new targets for immunotherapy against leptospira components. Leptospira, possess a wide variety of mechanisms that allow them to evade the host immune system and cause infection. Many molecules contribute to the ability of Leptospira to adhere, invade, and colonize. The recent sequencing of the Leptospira genome has increased our knowledge about this pathogen. Although the virulence factors, molecular targets, mechanisms of inflammation, and signaling pathways triggered by leptospiral antigens have been studied, some questions are still unanswered. Toll-like receptors (TLRs are the primary sensors of invading pathogens. TLRs recognize conserved microbial pattern molecules and activate signaling pathways that are pivotal to innate and adaptive immune responses. Recently, a new molecular target has emerged—the Na/K-ATPase—which may contribute to inflammatory and metabolic alteration in this syndrome. Na/K-ATPase is a target for specific fatty acids of host origin and for bacterial components such as the glycolipoprotein fraction (GLP that may lead to inflammasome activation. We propose that in addition to TLRs, Na/K-ATPase may play a role in the innate response to leptospirosis infection.

  12. Detection of reactive canines to Leptospira in Campeche City, Mexico Detección de caninos reaccionantes a Leptospira en la ciudad de Campeche, México

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    Selene del C Blum Domínguez

    2013-03-01

    Full Text Available Leptospira reactivity in stray and household dogs in Campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. The survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. Nine Leptospira interrogans serovars were tested by the microagglutination test. Reactivity was 21.3 % (69/323, 17.2 % corresponded to household dogs and 26.7 % to stray dogs. Leptospira Canicola (29 %, Leptospira Hardjo (22.58 %, and Leptospira Icterohaemorrhagiae (16.12 % were the most common serovars reacting against the serum of household animals, while Leptospira Canicola (15.78 %, Leptospira Icterohaemorrhagiae (13.15 %, and Leptospira Pomona (7.89 % were those reacting in stray dogs. Results showed that all dogs have been in contact with different Leptospira serovars and outdoor exposure is the main infection risk factor.

  13. Leptospires detection in kidney, liver and uterus of cows slaughtered in Paraná State, Brazil Detecção de leptospiras em rim, fígado e útero de fêmeas bovinas abatidas no estado do Paraná, Brasil

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    Francielle Gibson da Silva

    2005-03-01

    Full Text Available The objective of this trial was to detect leptospires in fragments of kidney, liver and uterus of 96 cows with unknown sanitary status, randomly chosen at slaughter in Paraná, Brazil. All 96 urine samples were submitted to direct examination using dark field microscopy. Positive samples in the direct examination and all kidney, liver and uterus fragments were cultured in EMJH modified medium and Tween 80/40/LH. Sections cut of kidney, liver and uterus were stained by Hematoxylin-Eosin (HE and indirect immunoperoxidase with hyperimmune serum against serovar Hardjo (Hardjoprajitno and strain Londrina 14 (LO14, from serovar Canicola, which was isolated in the northern region of Paraná state, Brazil, used as primary antibodies. Direct examination detected leptospires in the urine of four animals. All attempts to isolate leptospires from urine and kidney, liver and uterus fragments were negative after 16 weeks of incubation. In the HE stain, focal infiltrate of mononuclear inflammatory cells was observed in the renal interstitial area of most animals. In the indirect immunoperoxidase assay using hyperimmune serum against LO14 strain, the kidney of only one animal presented positive results. All fragments of kidney, liver and uterus tested with hyperimmune serum against serovar Hardjo were negative.O objetivo deste trabalho foi detectar leptospiras em fragmentos de rim, fígado e útero de 96 fêmeas bovinas com histórico sanitário desconhecido, escolhidas aleatoriamente durante o abate em um frigorífico no Estado do Paraná, Brasil. Todas as 96 amostras de urina foram submetidas ao exame direto em microscópio de campo escuro. As amostras positivas neste exame e todos os fragmentos de rim, fígado e útero foram semeados nos meios de cultura EMJH modificado e Tween 80/40/LH. Os cortes histológicos de rim, fígado e útero foram submetidos à coloração de Hematoxilina-Eosina (HE e a prova de imunoperoxidase indireta com soros hiperimunes

  14. Isolation of Leptospira from a phocid: acute renal failure and mortality from Leptospirosis in rehabilitated northern elephant seals (Mirounga angustirostris), California, USA.

    Science.gov (United States)

    Delaney, Martha A; Colegrove, Kathleen M; Spraker, Terry R; Zuerner, Richard L; Galloway, Renee L; Gulland, Frances M D

    2014-07-01

    During rehabilitation, acute renal failure due to leptospirosis occurred in eight male northern elephant seals (Mirounga angustirostris) that stranded along the central California coast in 2011. Characteristic histologic lesions including renal tubular degeneration, necrosis, and mineralization, and mild lymphoplasmacytic interstitial nephritis were noted in the six animals examined. Immunohistochemistry, bacterial culture, and PCR were positive in 2/3, 2/3, and 3/4 seals, respectively, and 6/8 had high serum antibody titers to Leptospira interrogans serovar pomona. Pulsed-field gel electrophoresis confirmed one isolate as serovar pomona. Variable number tandem repeat (VNTR) analysis showed both elephant seal isolates were identical to each other but distinct from those isolated from California sea lions (Zalophus californianus). The time from stranding to onset of azotemia was 1 to 38 (median=24) days, suggesting some seals were infected at the rehabilitation facility. Based on temporal and spatial incidence of infection, transmission among elephant seals likely occurred during rehabilitation. Molecular (VNTR) analysis of the two isolates indicates there is a unique L. interrogans serovar pomona genotype in elephant seals, and sea lions were not the source of infection prior to or during rehabilitation. This study confirms the susceptibility of northern elephant seals to leptospirosis, indicates intraspecies transmission during rehabilitation, and reports the first isolation and preliminary characterization of leptospires from elephant seals.

  15. Recurrent uveitis in horses: vitreal examinations with ultrastructural detection of leptospires.

    Science.gov (United States)

    Brandes, K; Wollanke, B; Niedermaier, G; Brem, S; Gerhards, H

    2007-06-01

    This study documents the examination of 17 horses (both sexes, 3-18 years old) suffering from spontaneous equine recurrent uveitis (ERU). Vitreal samples obtained by pars plana vitrectomy were examined macroscopically and ultrastructurally, and in most cases also by cultural examination, by microscopic agglutination test (MAT) and by polymerase chain reaction. In 24% (4/17) of the animals, ultrastructural examination by electron microscopy revealed intact leptospiral bacteria in the vitreous. The leptospires were detected freely in the vitreous and also incorporated by a phagocyte. They were surrounded by a rim of proteinaceous material which was reduced around a phagocytosed leptospira. Ninety-four per cent (16/17) of the vitreal samples presented significant antibody levels in the MAT, mostly against leptospiral serovar Grippotyphosa. Seventy-five per cent (9/12) of bacterial culture examinations were positive for leptospira. Polymerase chain reaction was positive in all (16/16) examinations performed. Our findings support previous reports suggesting that leptospires play an important role in the pathogenesis of ERU. Interestingly, this study found leptospires after secondary and later acute episodes. A persistent leptospiral infection is therefore suggested as the cause of ERU.

  16. Potent innate immune response to pathogenic leptospira in human whole blood.

    Directory of Open Access Journals (Sweden)

    Marga G A Goris

    Full Text Available BACKGROUND: Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. The bacteria enter the human body via abraded skin or mucous membranes and may disseminate throughout. In general the clinical picture is mild but some patients develop rapidly progressive, severe disease with a high case fatality rate. Not much is known about the innate immune response to leptospires during haematogenous dissemination. Previous work showed that a human THP-1 cell line recognized heat-killed leptospires and leptospiral LPS through TLR2 instead of TLR4. The LPS of virulent leptospires displayed a lower potency to trigger TNF production by THP-1 cells compared to LPS of non-virulent leptospires. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the host response and killing of virulent and non-virulent Leptospira of different serovars by human THP-1 cells, human PBMC's and human whole blood. Virulence of each leptospiral strain was tested in a well accepted standard guinea pig model. Virulent leptospires displayed complement resistance in human serum and whole blood while in-vitro attenuated non-virulent leptospires were rapidly killed in a complement dependent manner. In vitro stimulation of THP-1 and PBMC's with heat-killed and living leptospires showed differential serovar and cell type dependence of cytokine induction. However, at low, physiological, leptospiral dose, living virulent complement resistant strains were consistently more potent in whole blood stimulations than the corresponding non-virulent complement sensitive strains. At higher dose living virulent and non-virulent leptospires were equipotent in whole blood. Inhibition of different TLRs indicated that both TLR2 and TLR4 as well as TLR5 play a role in the whole blood cytokine response to living leptospires. CONCLUSIONS/SIGNIFICANCE: Thus, in a minimally altered system as human whole blood, highly virulent Leptospira are potent inducers of the cytokine response.

  17. Cross-reactivity of antibodies against leptospiral recurrent uveitis-associated proteins A and B (LruA and LruB with eye proteins.

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    Ashutosh Verma

    2010-08-01

    Full Text Available Infection by Leptospira interrogans has been causally associated with human and equine uveitis. Studies in our laboratories have demonstrated that leptospiral lipoprotein LruA and LruB are expressed in the eyes of uveitic horses, and that antibodies directed against LruA and LruB react with equine lenticular and retinal extracts, respectively. These reactivities were investigated further by performing immunofluorescent assays on lenticular and retinal tissue sections. Incubation of lens tissue sections with LruA-antiserum and retinal sections with LruB-antiserum resulted in positive fluorescence. By employing two-dimensional gel analyses followed by immunoblotting and mass spectrometry, lens proteins cross-reacting with LruA antiserum were identified to be alpha-crystallin B and vimentin. Similarly, mass spectrometric analyses identified beta-crystallin B2 as the retinal protein cross-reacting with LruB-antiserum. Purified recombinant human alpha-crystallin B and vimentin were recognized by LruA-directed antiserum, but not by control pre-immune serum. Recombinant beta-crystallin B2 was likewise recognized by LruB-directed antiserum, but not by pre-immune serum. Moreover, uveitic eye fluids contained significantly higher levels of antiibodies that recognized alpha-crystallin B, beta-crystallin B2 and vimentin than did normal eye fluids. Our results indicate that LruA and LruB share immuno-relevant epitopes with eye proteins, suggesting that cross-reactive antibody interactions with eye antigens may contribute to immunopathogenesis of Leptospira-associated recurrent uveitis.

  18. Seroepidemiological detection of antibodies against Leptospira spp using microscopic agglutination test in Urmia cows and sheep

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    Ramin Ag

    2013-01-01

    Full Text Available The study was designed to determine the level of incidence, titer and various serovars of leptospira in 203 cows and 166 sheep at Urmia abattoir in 2011. Blood samples were collected during the slaughter of animals and sera were separated to evaluate the serological reaction to Leptospira spp by Microscopic Agglutination Test (MAT using live antigens representing Leptospira interrogans serogroups: pomona, grippotyphosa, canicola, hardjo, icterrohaemoragiae, and ballum. Overall, 36% of cows and 19.3% of sheep including 33.8% of bulls, 40.5% of female cows, 18.3% of rams and 25% of ewes had a positive reaction to at least one of the leptospira serovars. The most prevalent serovars in cows were pomona (22.7%, grippotyphosa (13.8%, and hardjo (8.4%, and in sheep were grippotyphosa (66.7%, pomona (26.2% and canicola (7.1%. Other serovars were not detected in cows and sheep. The most prevalent serological titers of 1:100 and 1:200 in cows was 18.2% and 26.6%, and for sheep were 13.5% and 8%, respectively, and of 1:400 in sheep was 2.3%. Cows with a positive reaction to one, two and three serovars were 28.6%, 5.9%, and 1.5% and sheep positive to one and two serovars were 13.3% and 6%, respectively. Age comparison in seropositive cows and sheep showed a significantly increased infection (p<0.05 from young to adult ruminants, while no differences were seen regarding gender. The main mixed serovars were between grippotyphosa/pomona, grippotyphosa/canicola and canicola/pomona. The gender comparison of the serovars' distribution revealed that the pomona and grippotyphosa were predominant among other leptospiral serovars in cows and sheep, respectively. In conclusion, the rate of leptospirosis in Urmia cows was about 2 fold in sheep. The most current serovars in cows and sheep were pomona and grippotyphosa, respectively. The majority of animals was infected with one serovar, but polyserovars, are also possible. The highest titer (1:200 was observed in cows

  19. The prevalence of Leptospira sp in sewer rats (Rattus norvegicus)

    DEFF Research Database (Denmark)

    Krøigaard, Louise; Villumsen, Steen; Markussen, Mette Drude

    , L. santarosai, L. meyeri, L. interrogans, L. weilii and L. borgpetersenii by PCR. PCR was performed on DNA extracted from kidneys with primer G1/G2 which amplifies a leptospira DNA fragment of 285 bp. For determination of leptospira serovar types, PCR was combined with MAT (Microscopic Agglutination...

  20. Use of flow cytometry for rapid and accurate enumeration of live pathogenic Leptospira strains.

    Science.gov (United States)

    Fontana, Célia; Crussard, Steve; Simon-Dufay, Nathalie; Pialot, Daniel; Bomchil, Natalia; Reyes, Jean

    2017-01-01

    Enumeration of Leptospira, the causative agent of leptospirosis, is arduous mainly because of its slow growth rate. Rapid and reliable tools for numbering leptospires are still lacking. The current standard for Leptospira cultures is the count on Petroff-Hausser chamber under dark-field microscopy, but this method remains time-consuming, requires well-trained operators and lacks reproducibility. Here we present the development of a flow-cytometry technique for counting leptospires. We showed that upon addition of fluorescent dyes, necessary to discriminate the bacterial population from debris, several live Leptospira strains could be enumerated at different physiologic states. Flow cytometry titers were highly correlated to counts with Petroff-Hausser chambers (R(2)>0.99). Advantages of flow cytometry lie in its rapidity, its reproducibility significantly higher than Petroff-Hausser method and its wide linearity range, from 10(4) to 10(8)leptospires/ml. Therefore, flow cytometry is a fast, reproducible and sensitive tool representing a promising technology to replace current enumeration techniques of Leptospira in culture. We were also able to enumerate Leptospira in artificially infected urine and blood with a sensitivity limit of 10(5)leptospires/ml and 10(6)leptospires/ml, respectively, demonstrating the feasibility to use flow cytometry as first-line tool for diagnosis or bacterial dissemination studies.

  1. Interactions of virulent and avirulent leptospires with primary cultures of renal epithelial cells

    DEFF Research Database (Denmark)

    Ballard, S A; Williamson, M; Adler, B

    1986-01-01

    A primary culture system for the cells of mouse renal-tubular epithelium was established and used to observe the adhesion of leptospires. Virulent strains of serovars copenhageni and ballum attached themselves to epithelial cells within 3 h of infection whereas an avirulent variant of serovar...... copenhageni did not adhere to epithelial cells at all within the experimental period of 24 h. The saprophytic Leptospira biflexa serovar patoc became attached non-specifically to inert glass surfaces as well as to the cells. The adhesion of leptospires to epithelial cells was not inhibited by homologous...

  2. Molecular Detection of Leptospiral DNA in Environmental Water on St. Kitts

    Directory of Open Access Journals (Sweden)

    Julienne Rawlins

    2014-08-01

    Full Text Available Leptospirosis is an important waterborne zoonotic disease caused by pathogenic Leptospira. The pathogen is maintained in a population due to chronic colonization and shedding from renal tubules of domestic and wild animals. Humans and other animals become infected when they come in contact with urine from infected animals, either directly or through urine-contaminated surface water. In this study, we screened environmental water on the island of St. Kitts by using a TaqMan based real time quantitative polymerase chain reaction (qPCR targeting a pathogen specific leptospiral gene, lipl32. Our results indicate that around one-fifth of tested water sources have detectable leptospiral DNA.

  3. Expression pattern and apoptosis-inducing activity to murine macrophages and hepatocytes of Leptospira interrogans Sph2 hemolysin%钩端螺旋体溶血素Sph2表达模式及诱导巨噬细胞和肝细胞凋亡活性

    Institute of Scientific and Technical Information of China (English)

    丁士标; 林旭瑷; 王欢; 严杰

    2010-01-01

    目的 了解问号钩端螺旋体(简称钩体)感染细胞前后sph2基因表达水平变化,确定鞘磷脂酶类溶血素Sph2及诱导细胞凋亡的活性.方法 采用PCR从黄疸出血群赖型赖株钩体基因组DNA中扩增全长sph2基因片段,T-A克隆后测序.构建sph2基因原核表达系统,采用SDS-PAGE检查重组Sph2(rSph2)的表达情况,Ni-NTA亲和层析法提纯rSph2.采用绵羊血平板溶血试验及血红蛋白分光光度法测定rSph2的溶血活性.采用流式细胞术检测rSph2诱导小鼠单核-巨噬样细胞株J774A.1和肝细胞株IAR20凋亡的活性,实时荧光定量PCR检测赖株钩体感染J774A.1和IAR20细胞前后sph2基因mRNA水平变化.结果 与GenBank中sph2基因比较,所克隆的sph2基因序列相似性为100%.所构建的原核表达系统能高效表达rSph2.rSph2以浓度依赖方式溶解绵羊红细胞.10 μg/ml rSph2可诱导J774A.1和IAR20细胞凋亡,凋亡率峰值分别为23.96%和32.92%.赖株钩体感染J774A.1和IAR20细胞后0.5~2 h内sph2基因mRNA水平显著升高,2 h后mRNA水平迅速下降.结论 钩体sph2基因呈宿主细胞接触式瞬时表达.rSph2有溶解绵羊红细胞及诱导巨噬细胞和肝细胞凋亡的活性,因而Sph2是钩体致病过程中重要的毒力因子.%Objective To determine the change of expression level of Leptospira interrogans sph2 gene, and hemolytic and cell apoptosis-inducing activities of sphingomyelinase hemolysin Sph2. Methods Entire sph2 gene fragment was amplified by PCR from genomic DNA of L. Interrogans serovar serogroup Icterohaemorrhagiae serovar Lai strain Lai, and sequenced after T-A cloning. Subsequently, a prokaryotic expression system of sph2 gene was constructed. The expression of target recombinant Sph2( rSph2 ) was examined by SDS-PAGE and the expressed rSph2 was extracted by Ni-NTA affinity chromatogaphy. The hemolytic activity of rSph2 was measured by hemolytic test in sheep blood agar plate and spectrophotometry-based hemoglobin

  4. Use of saprophytic leptospira strains in the serodiagnosis of experimental leptospirosis in guinea-pigs (Cavia sp

    Directory of Open Access Journals (Sweden)

    Raul J. S. Girio

    1988-04-01

    Full Text Available The efficiency of four Leptospira biflexa strains (Buenos Aires, Patoc 1, Rufino and São Paulo as single antigen in the serodiagnosis in guinea-pigs experimentally infected with seven Leptospira interrogans serovars (canicola, grippotyphosa, hardjo, icterohaemorrhagiae, pomona, tarassovi and wolffi was evaluated by the microscopic agglutination test. The four saprophytic strains were not able to reveal antibody titres in sera of guinea-pigs experimentally infected with Leptospira interrogans. Serological cross-reactions were observed between strains Patoc 1 and São Paulo and between serovars wolffi and hardjo.

  5. Conservation of the S10-spc-alpha Locus within Otherwise Highly Pastic Genomes Provides Phylogenetic Insight into the Genus Leptospira

    Science.gov (United States)

    A comparative analysis of the Leptospira interrogans S10-spc-alpha operon was performed by PCR using primer sets covering the whole operon. Correctly sized fragments were obtained by PCR from all of L. interrogans strains for each primer set indicating that the S10-spc-alpha locus is well conserved ...

  6. Functional analysis of Leptospira interrogans sphingomyelinase hemolysin genes and their transcriptional level alterations in the infected host cells%问号钩端螺旋体鞘磷脂酶类溶血素基因功能分析及其感染细胞后转录水平变化

    Institute of Scientific and Technical Information of China (English)

    赵金方; 林旭嫒; 严杰

    2009-01-01

    Objective To determine the hemolytic activity of products of sphingomyelinase hemolysin encoding genes of Leptospira interrogaas, and the transcriptional level alterations in the infected host cells. Methods By using genomic DNAs of pathogenic L. interrogans serovar serogroup Icterohaemorrhagiae serovar Lai strain Lai and serogroup Pomona serovar Pomona strain Luo, and non-pathogenic L. biflexa serogroup Sama-ranga serovar Patoc strain Patoc Ⅰ as templates, PCRs were performed to amplify entire sph1-sph4 genes. The amplified products were sequenced after T-A cloning. Prokaryotic expression systems of sph1-sph4 genes were re-spectively constructed, and the expressions of target recombinant proteins rSph1-rSph4 were examined by SDS-PAGE. Ni-NTA affinity chromatographic column was used to extract the expressed rSph1-rSph4. Hemolytic ac-tivities of rSph1-rSph4 on sheep blood agar plate were identified. Transcription alterations of sphl-sph4 genes in L. interrogans strain Lai after infected J774A. 1 cells were measured by real-time fluorescence quantitative RT-PCR. Results From genomic DNAs of both L. interrogans strain Lai and Luo, but not from that of L. biflexa strain Patoc Ⅰ , the target fragments of sph1-sph4 genes could be amplified. All the cloned sph1-sph4 genes had 100% nucleotide sequence identities compared to the corresponding reported sequences. The constructed pro-karyotic expression systems were able to efficiently express the target recombinant proteins rSph1-rSph4, respec-tively. All the rSph1-rSph4 had hemolytic activities, and among the four products rSph2 displayed the strongest hemolytic activity. After L. interrogaas strain Lai infecting J774A. 1 cells, the transcriptional levels of sph1-sph4 genes were remarkably up-regulated, especially for mRNA levels of sph2 and sph4 genes. Conclusion sph1- sph4 genes exist only in pathogenic L. interrogans species, and their products have hemolytic activity. The up-regulation of sph1-sph4 gene

  7. An Epidemiological Study of Leptospira-Induced Abortion in Mares in Central Kentucky (1990-2004)

    Science.gov (United States)

    2005-02-02

    effects of temperature, precipitation, and naturally occurring water location on equine leptospiral abortions . It is important, therefore, to look at...precipitation and that the two act in tandem to cause the effect . As mentioned earlier, the most likely cause of death of a leptospire in the natural...EPIDEMIOLOGICAL STUDY OF LEPTOSPIRA-INDUCED ABORTION IN MARES IN CENTRAL KENTUCKY (1990-2004) 6. AUTHOR(S) CAPT HALL DAVID C 7. PERFORMING

  8. Molecular Characterization of Leptospira spp. in Environmental Samples from North-Eastern Malaysia Revealed a Pathogenic Strain, Leptospira alstonii

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    Muhammad Azharuddin Azali

    2016-01-01

    Full Text Available The presence of pathogenic Leptospira spp. in the environment poses threats to human health. The aim of this study was to detect and characterize Leptospira spp. from environmental samples. A total of 144 samples comprised of 72 soil and 72 water samples were collected from markets and recreational areas in a north-eastern state in Malaysia. Samples were cultured on Ellinghausen and McCullough modified by Johnson and Harris media. Leptospires were positive in 22.9% (n=33 of the isolates. Based on partial sequences of 16S rRNA, a pathogenic leptospire, Leptospira alstonii (n=1/33, was identified in 3% of the isolates followed by intermediate leptospire (L. wolffii, n=1/33, and L. licerasiae, n=7/33 and nonpathogenic leptospire, L. meyeri (n=22/33 in 24.2% and 66.7%, respectively. This study demonstrates the presence of a clinically significant pathogenic L. alstonii in the environments which could pose health risks to the occupants and visitors.

  9. Molecular Characterization of Leptospira spp. in Environmental Samples from North-Eastern Malaysia Revealed a Pathogenic Strain, Leptospira alstonii

    Science.gov (United States)

    Azali, Muhammad Azharuddin; Yean Yean, Chan; Aminuddin Baki, Nurul Najian

    2016-01-01

    The presence of pathogenic Leptospira spp. in the environment poses threats to human health. The aim of this study was to detect and characterize Leptospira spp. from environmental samples. A total of 144 samples comprised of 72 soil and 72 water samples were collected from markets and recreational areas in a north-eastern state in Malaysia. Samples were cultured on Ellinghausen and McCullough modified by Johnson and Harris media. Leptospires were positive in 22.9% (n = 33) of the isolates. Based on partial sequences of 16S rRNA, a pathogenic leptospire, Leptospira alstonii (n = 1/33), was identified in 3% of the isolates followed by intermediate leptospire (L. wolffii, n = 1/33, and L. licerasiae, n = 7/33) and nonpathogenic leptospire, L. meyeri (n = 22/33) in 24.2% and 66.7%, respectively. This study demonstrates the presence of a clinically significant pathogenic L. alstonii in the environments which could pose health risks to the occupants and visitors. PMID:27127522

  10. Pathogenic Leptospires Modulate Protein Expression and Post-translational Modifications in Response to Mammalian Host Signals

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    Jarlath E. Nally

    2017-08-01

    Full Text Available Pathogenic species of Leptospira cause leptospirosis, a bacterial zoonotic disease with a global distribution affecting over one million people annually. Reservoir hosts of leptospirosis, including rodents, dogs, and cattle, exhibit little to no signs of disease but shed large numbers of organisms in their urine. Transmission occurs when mucosal surfaces or abraded skin come into contact with infected urine or urine-contaminated water or soil. Whilst little is known about how Leptospira adapt to and persist within a reservoir host, in vitro studies suggest that leptospires alter their transcriptomic and proteomic profiles in response to environmental signals encountered during mammalian infection. We applied the dialysis membrane chamber (DMC peritoneal implant model to compare the whole cell proteome of in vivo derived leptospires with that of leptospires cultivated in vitro at 30°C and 37°C by 2-dimensional difference in-gel electrophoresis (2-D DIGE. Of 1,735 protein spots aligned across 9 2-D DIGE gels, 202 protein spots were differentially expressed (p < 0.05, fold change >1.25 or < −1.25 across all three conditions. Differentially expressed proteins were excised for identification by mass spectrometry. Data are available via ProteomeXchange with identifier PXD006995. The greatest differences were detected when DMC-cultivated leptospires were compared with IV30- or IV37-cultivated leptospires, including the increased expression of multiple isoforms of Loa22, a known virulence factor. Unexpectedly, 20 protein isoforms of LipL32 and 7 isoforms of LipL41 were uniformly identified by DIGE as differentially expressed, suggesting that unique post-translational modifications (PTMs are operative in response to mammalian host conditions. To test this hypothesis, a rat model of persistent renal colonization was used to isolate leptospires directly from the urine of experimentally infected rats. Comparison of urinary derived leptospires to IV30

  11. Leptospira wolffii, a potential new pathogenic Leptospira species detected in human, sheep and dog.

    Science.gov (United States)

    Zakeri, Sedigheh; Khorami, Nargess; Ganji, Zahra F; Sepahian, Neda; Malmasi, Abdol-Ali; Gouya, Mohammad Mehdi; Djadid, Navid D

    2010-03-01

    Leptospirosis is the most common zoonotic disease, which is transmitted to humans through contaminated water or direct exposure to the urine of infected animals. In this study, the presence and prevalence of Leptospira species in the infected samples of human (n=369) and sheep (n=75) sera and also dogs' urine (n=150), collected from four provinces of Iran, were investigated by using nested-PCR/RFLP assay followed by sequencing analysis. Nested-PCR assay detected that 98/369 (26.5%) human, 13/75 (17.33%) of sheep's sera and 33/150 (22%) dogs' urine samples were positive for Leptospira DNA. RFLP assay detected that all positive cases had either pathogenic or intermediate Leptospira species. By sequence analysis, Leptospira interrogans was the most prevalent species among the examined samples of human (53/82, 64.6%) and sheep (11/13, 84.6%). However, in dog samples, Leptospira wolffii (27/29, 93.1%) was detected for the first time and was the dominant species. The presence of L. wolffii with 100% identity in clinical human samples and animals suspected with Leptospira may provide evidence for circulation of L. wolffii and its role in transmission cycle within human and animal hosts. In addition, this species can be potentially pathogenic to human and probably animal hosts. A large epidemiology survey would be needed to define the presence and the prevalence of this species in global endemic regions.

  12. Detection of Leptospiral DNA in the Urine of Donkeys on the Caribbean Island of Saint Kitts

    Directory of Open Access Journals (Sweden)

    Bernard Grevemeyer

    2017-01-01

    Full Text Available Leptospirosis is a global zoonosis caused by pathogenic spirochetes classified within the genus Leptospira. Leptospires live in the proximal renal tubules of reservoir or chronic carrier animals, and are shed in the urine. Naïve animals acquire infection either when they come in direct contact with a reservoir or infected animals or by exposure to environmental surface water or soil that is contaminated with their urine. In this study, urine samples from a herd of donkeys on the Caribbean island of St. Kitts were screened using a TaqMan-based real-time quantitative polymerase chain reaction (qPCR targeting a pathogen-specific leptospiral gene, lipl32. Out of 124 clinically normal donkeys, 22 (18% tested positive for leptospiral DNA in their urine. Water samples from two water troughs used by the donkeys were also tested, but were found to be free from leptospiral contamination. Detection of leptospiral DNA in the urine of clinically healthy donkeys may point to a role that these animals play in the maintenance of the bacteria on St. Kitts.

  13. Leptospira interrogans inducing apoptosis of macrophages through mitochondria-associated signaling pathway%问号钩端螺旋体经线粒体相关信号通路诱导巨噬细胞凋亡的研究

    Institute of Scientific and Technical Information of China (English)

    范兴丽; 董海艳; 严杰

    2009-01-01

    Objective To determine mitochondria-associated signaling pathway on cell apoptosis in Leptospira interrogans infected murine mononuclear-macrophages. Methods A cell apoptotic model of L. interrogan serogroup Icterohaemorrhagiae strain Lai inducing apoptosis of murine mononuclear-macrophage line (J774A. 1) was established. Pathological changes of mitochondria in the infected cells were observed under transmission electron microscope. Mitochondrial potential and reactive oxygen species(ROS) levels in the infected cells were detected using JC-1 staining method and DCFH-DA fluorescent probe, respectively,and caspase-8/-9 activities in the infected cells were measured using commercial kits. and the apoptosis block effects of caspase inhibitors were determined by flow cytometry. Apoptosis in the infected cells and ap-optosis-blocking effect by caspase inhibitors were detected by flow cytometry. Western blot assay was adopted to examine the levels of cytochrome C (CytC) , AIF, EndoG and Smae in the mitochondria and cytoplasm.The transposition of either AIF or EndoG from the cytoplasm into cell nucleus was determined by immunoflu-orescence staining test. Results L. interrogans strain Lai could induce J774A. 1 cell apoptoais. In the in-fected cells, visible mitochondrial injury, declined mitochondrial membrane potential and elevated ROS level were presented. The activity of caspase-8 but not of caspase-9 was significantly increased. The caspase in-hihitors could not completely block the cell apoptosis. Both the AIF and EndoG was released from the mito-chondria and subsequently transferred from the cytoplasm into the nucleus in the infected cells. However,elevation of CytC level and Smac release in cytoplasm of the infected cells could not be found. Conclusion L.interrogans can induce apoptosis in the infected mononuclear-macrophage via AIF and EndoG belonging to caspase-independent pathway.%目的 确定线粒体相关信号转导途径在问号钩端螺旋体(简称钩

  14. Seroprevalence of leptospiral Antibodies in Humans and Domestic Animals in Iran

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    Ehsanollah Sakhaee

    2015-10-01

    Full Text Available Background: Leptospirosis is an important re-emerging zoonotic disease in tropical and subtropical areas and acute febrile infection and a conveyable bacterial disease of animals and humans caused by pathogenic spirochetes of the genus Leptospira.Methods: Five hundred and ninety seven serum samples (159 cattle, 142 sheep, 147 goats and 149 humans were collected from center, southeast and northeast of Iran. MAT was performed mainly as described by Turner with some modification in Leptospira Research Laboratory.Results: Antibodies were detected at least against one serovar of Leptospira interrogans in 97 sera (17.24% among 597 samples at a dilution 1:100 or greater.Conclusion: The most prevalent serovar was icterohaemorrhagiae and the least prevalent was canicula.

  15. Adenosine deaminase activity in serum, erythrocytes and lymphocytes of rats infected with Leptospira icterohaemorrhagiae.

    Science.gov (United States)

    Tonin, Alexandre A; Pimentel, Victor C; da Silva, Aleksandro S; de Azevedo, Maria Isabel; Souza, Viviane C G; Wolkmer, Patrícia; Rezer, João F P; Badke, Manoel R T; Leal, Daniela B R; Schetinger, Maria Rosa C; Monteiro, Silvia G; Lopes, Sonia T A

    2012-04-01

    Leptospirosis is a systemic disease of humans and domestic animals, mainly dogs, cattle and swine. The course of human leptospirosis varies from mild to severe fatal forms and the most severe form of human leptospirosis is principally caused by Leptospira interrogans serovar icterohaemorrhagiae (L. icterohaemorrhagiae). The enzyme adenosine deaminase (ADA) plays an important role in the production and differentiation of blood cells. The aim of this study was to evaluate the activity of ADA in serum, erythrocytes and lymphocytes of rats infected with L. icterohaemorrhagiae, as compared with non-infected rats. Twenty-four adult rats, divided into two uniform groups (A and B) were used for the enzymatic assays. The animals in Group B were inoculated intraperitoneally with 2×10(8) leptospires/rat, and the rodents in Group A (control) were not-inoculated. Blood collection was performed on days 5 and 15 post-infection (PI) and the blood used to assess the ADA activity. The infection by L.icterohaemorrhagiae altered erythrocyte count, hemoglobin concentration and hematocrit, causing a decrease in all these parameters on day 15 PI. Lymphocytes decreased significantly on day 15 PI, and ADA activity in serum was inhibited in infected rats on days 5 and 15 PI and its activity in erythrocytes were increased on day 5 PI. On day 5 PI, we found an increase in ADA activity in erythrocytes of infected rats. No correlation was observed between hematocrit and erythrocyte ADA activity on days 5 and 15 PI. The ADA activity was inhibited in rats infected on day 15 PI. A positive correlation (r(2)=60) was also observed between the number of lymphocytes and ADA activity in lymphocytes on day 15 PI (Perythrocytes in experimental infection by L.icterohaemorrhagiae in rats, concomitantly with hematological parameters.

  16. [Nucleotide sequence analysis of a species specific probe by an inserted fragment from recombinant plasmid pCX7 of L. interrogans sensu stricto serovar lai].

    Science.gov (United States)

    Dai, B; Xiao, J; Yan, Z; Shen, C; Li, S; Fang, Z

    1998-12-01

    The etiological agents of leptospirosis are the pathogenic leptospires (L. interrogans sensu lato) which can be divided into 223 serovars organized into 23 serogroups. The serovar remains the basic taxon, but serotyping may now be accomplished and recognized by acceptable methods. Complementary molecular approaches are being used extensively to assess genetic relatedness amongst leptospires with restriction endonuclese analysis (REA), pulse field gel electrophoresis (PFGE) and DNA-DNA hybridization as well established tools. However, the method is cumbersome and unsuitable for routine application. To develop a sensitive and specific method for identification of pathogenic leptospires, a genomic library of L. interrogans sensu stricto serovar lai was constructed with the plasmid vector pUC9. A recombinant plasmid, designated pCX7 which has homologous fragment of pathogenic leptospires was screened from the bank. pCX7 could recognize pathogenic leptospiral DNA fragment 1.7 kb of strain 017 without cross hybridization to nonpathogenic leptospiral DNA. Inserted fragment of pCX7 DNA sequencing was performed by Dr. Yan Zhengxin (Max-Plank-Institut fur Biology, Tubingen, Germany). Insert fragment was cloned into pBluescript and sequenced by using ABI(Applied Bio. Systems, Model 373A). Nucleotide sequences were analyzed by Dr. Xiao Jianguo (Texas University Medical School and School of Public Health, Center for Infectious Diseases) using a suit of computer program (NIH). One open reading frame of 306 nucleotids were identified. There were identifiable initiation codons, terminators, pribnow box and sextama box within the sequenced regions. These results further confirmed that the little homology between L. interrogans sensu strito and L. borgpeterseni serovar javanica, L. inadai serovar ranarun and serovar manhao (L. genomospecies 2), L. biflexa serovar patoc, L. illini. pCX7 DNA probe could provide a base for identification and classification of leptospires.

  17. Prokaryotic expression of tlyA gene of Leptospira interrogans strain and the significance of the ex-pressed protein in hemolysis and inflammation%问号钩端螺旋体 tlyA 基因原核表达及其表达产物溶血和致炎作用

    Institute of Scientific and Technical Information of China (English)

    王欢; 林旭瑷; 周永列; 邱莲女; 严杰

    2015-01-01

    目的:构建问号钩端螺旋体(简称钩体) tlyA基因原核表达系统,确定目的重组表达产物rTlyA溶解红细胞及诱导人THP-1和小鼠J774A.1巨噬细胞分泌致炎细胞因子的作用。方法采用PCR扩增问号钩体黄疸出血群赖型赖株tlyA基因,T-A克隆后测序。采用原核表达载体pET-42a及表达宿主菌E.coli BL21DE3构建tlyA基因原核表达系统。采用SDS-PAGE检测rTlyA表达情况, Ni-NTA亲和层析法提纯rTlyA。采用平板法和分光光度法测定rTlyA对绵羊红细胞的溶血活性。采用RT-PCR和Western blot分别检测问号钩体赖株感染THP-1和J774A.1细胞后tlyA基因mRNA水平变化及TlyA外分泌情况。采用ELISA检测rTlyA诱导THP-1和J774A.1细胞分泌致炎细胞因子IL-1β、IL-6和TNF-α的作用。结果所克隆的tlyA基因与GenBank中公布的相应基因核苷酸和氨基酸序列相似性分别为99.2%和99.8%。所构建的tlyA基因原核表达系统能有效表达rTlyA。10μg/ml rTlyA能显示较强的溶解绵羊红细胞活性。问号钩体赖株感染THP-1和J774A.1细胞1~8 h后,tlyA-mRNA水平显著升高(P<0.05)且出现TlyA外分泌。0.1、1和10μg/ml rTlyA均能使THP-1和J774A.1细胞分泌致炎细胞因子IL-1β、IL-6和TNF-α的水平显著升高(P<0.05)。结论问号钩体tlyA基因产物TlyA是溶血素并能诱导巨噬细胞分泌IL-1β、IL-6和TNF-α,可在钩体病炎症反应中发挥重要作用。%Objective To construct a prokaryotic expression system for tlyA gene of Leptospira in-terrogans ( L.interrogans) strain and to investigate the effects of the expressed rTlyA protein on the hemolysis of sheep erythrocytes and the secretion of pro-inflammatory cytokines by human THP-1 cells and murine J774A.1 macrophages.Methods The fragment of tlyA gene of L.inetrrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai was amplified by PCR.The PCR product was sequenced after T

  18. Evidence of Rickettsial and Leptospira Infections in Andean Northern Peru

    Science.gov (United States)

    2004-01-01

    about health in six Latin American countries, 1973- 1992. Rev Panam Salud Publica 1: 23–34. 3. Cowan G, 2000. Rickettsial diseases: the typhus group of...Leonardo Mendoza Instituto Nacional de Salud , Capac Yupanqui No. 1400, Jesús Maria, Lima 11, Peru, Telephone: 51-1-471-9920. Allen L. Richards, Viral and...Colli C, 1997. Leptospira interrogans in a canine population of greater Bue- nos Aires: variables associated with seropositivity. Rev Panam Salud

  19. Draft Genome Sequence of the First Pathogenic Leptospira Isolates from Ecuador.

    Science.gov (United States)

    Barragan, Veronica; Sahl, Jason W; Wiggins, Kristin; Chiriboga, Jorge; Salinas, Ana; Cantos, Nancy E; Loor, Mariana N; Intriago, Bertha I; Morales, Melba; Trueba, Gabriel; Pearson, Talima

    2016-05-05

    Pathogenic Leptospira spp. cause leptospirosis upon contact with mucosa through wounds or ingestion, leading to headaches, fever, jaundice, kidney or liver failure, or death in about 1.3 million people each year. Here, we present the draft genomes of one L. santarosai isolate and two L. interrogans isolates from Ecuador.

  20. Draft Genome Sequence of the First Pathogenic Leptospira Isolates from Ecuador

    OpenAIRE

    Barragan, Veronica; Sahl, Jason W.; Wiggins, Kristin; Chiriboga, Jorge; Salinas, Ana; Cantos, Nancy E.; Loor, Mariana N.; Intriago, Bertha I.; Morales, Melba; Trueba, GAbriel; Pearson, Talima

    2016-01-01

    Pathogenic Leptospira spp. cause leptospirosis upon contact with mucosa through wounds or ingestion, leading to headaches, fever, jaundice, kidney or liver failure, or death in about 1.3 million people each year. Here, we present the draft genomes of one L. santarosai isolate and two L. interrogans isolates from Ecuador.

  1. Modulation of Hemostatic and Inflammatory Responses by Leptospira Spp.

    Science.gov (United States)

    Vieira, Mônica L.; Naudin, Clément; Mörgelin, Matthias; Romero, Eliete C.; Nascimento, Ana Lucia T. O.; Herwald, Heiko

    2016-01-01

    Leptospirosis is a worldwide spread zoonotic and neglected infectious disease of human and veterinary concern that is caused by pathogenic Leptospira species. In severe infections, hemostatic impairments such as coagulation/fibrinolysis dysfunction are frequently observed. These complications often occur when the host response is controlled and/or modulated by the bacterial pathogen. In the present investigation, we aimed to analyze the modulation of the hemostatic and inflammatory host responses by the bacterial pathogen Leptospira. The effects of leptospires and their secreted products on stimulation of human intrinsic and extrinsic pathways of coagulation were investigated by means of altered clotting times, assembly and activation of contact system and induction of tissue factor. We show that both extrinsic and intrinsic coagulation cascades are modulated in response to Leptospira or leptospiral secreted proteins. We further find that the pro-inflammatory mediator bradykinin is released following contact activation at the bacterial surface and that pro-coagulant microvesicles are shed from monocytes in response to infection. Also, we show that human leptospirosis patients present higher levels of circulating pro-coagulant microvesicles than healthy individuals. Here we show that both pathways of the coagulation system are modulated by leptospires, possibly leading to altered hemostatic and inflammatory responses during the disease. Our results contribute to the understanding of the leptospirosis pathophysiological mechanisms and may open new routes for the discovery of novel treatments for the severe manifestations of the disease. PMID:27167223

  2. Molecular characterization of Leptospira sp by multilocus variable number tandem repeat analysis (MLVA from clinical samples: a case report

    Directory of Open Access Journals (Sweden)

    Hélène Pailhoriès

    2015-08-01

    Full Text Available Leptospirosis is a zoonotic infection for which diagnosis is difficult. It has appeared as a global emerging infectious disease over recent years. Genotype determination often requires a Leptospira strain obtained by culture, which is a long and fastidious technique. A method based on multilocus variable number tandem repeat analysis (MLVA to determine the genotype of Leptospira interrogans, performed directly on blood or urine samples, is proposed. This method was applied to a fatal case of leptospirosis for which the geographical origin of infection was unknown. This technique will allow a genotype to be obtained for L. interrogans, even when cultures remain negative.

  3. Molecular typing of Leptospira spp. strains isolated from field mice confirms a link to human leptospirosis.

    Science.gov (United States)

    Li, S J; Wang, D M; Zhang, C C; Li, X W; Yang, H M; Tian, K C; Wei, X Y; Liu, Y; Tang, G P; Jiang, X G; Yan, J

    2013-11-01

    In recent years, human leptospirosis has been reported in Jinping and Liping counties, Guizhou province, but the leptospires have never been isolated. To track the source of infection and understand the aetiological characteristics, we performed surveillance for field mice carriage of leptospirosis in 2011. Four strains of leptospire were isolated from Apodemus agrarius. PCR confirmed the four isolates as pathogenic. Multiple-locus variable-number tandem repeat analysis (MLVA) showed that the four strains were closely related to serovar Lai strain 56601 belonging to serogroup Icterohaemorrhagiae, which is consistent with the antibody detection results from local patients. Furthermore, the diversity of leptospiral isolates from different hosts and regions was demonstrated with MLVA. Our results suggest that A. agrarius may be the main carrier of Leptospira in Jinping and Liping counties, and the serogroup Icterohaemorrhagiae serovar may be the epidemic serogroup of Leptospira. This will contribute to the control and prevention of leptospirosis in these localities.

  4. High Prevalence of Intermediate Leptospira spp. DNA in Febrile Humans from Urban and Rural Ecuador.

    Science.gov (United States)

    Chiriboga, Jorge; Barragan, Verónica; Arroyo, Gabriela; Sosa, Andrea; Birdsell, Dawn N; España, Karool; Mora, Ana; Espín, Emilia; Mejía, María Eugenia; Morales, Melba; Pinargote, Carmina; Gonzalez, Manuel; Hartskeerl, Rudy; Keim, Paul; Bretas, Gustavo; Eisenberg, Joseph N S; Trueba, Gabriel

    2015-12-01

    Leptospira spp., which comprise 3 clusters (pathogenic, saprophytic, and intermediate) that vary in pathogenicity, infect >1 million persons worldwide each year. The disease burden of the intermediate leptospires is unclear. To increase knowledge of this cluster, we used new molecular approaches to characterize Leptospira spp. in 464 samples from febrile patients in rural, semiurban, and urban communities in Ecuador; in 20 samples from nonfebrile persons in the rural community; and in 206 samples from animals in the semiurban community. We observed a higher percentage of leptospiral DNA-positive samples from febrile persons in rural (64%) versus urban (21%) and semiurban (25%) communities; no leptospires were detected in nonfebrile persons. The percentage of intermediate cluster strains in humans (96%) was higher than that of pathogenic cluster strains (4%); strains in animal samples belonged to intermediate (49%) and pathogenic (51%) clusters. Intermediate cluster strains may be causing a substantial amount of fever in coastal Ecuador.

  5. Reverse Vaccinology: An Approach for Identifying Leptospiral Vaccine Candidates

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    Odir A. Dellagostin

    2017-01-01

    Full Text Available Leptospirosis is a major public health problem with an incidence of over one million human cases each year. It is a globally distributed, zoonotic disease and is associated with significant economic losses in farm animals. Leptospirosis is caused by pathogenic Leptospira spp. that can infect a wide range of domestic and wild animals. Given the inability to control the cycle of transmission among animals and humans, there is an urgent demand for a new vaccine. Inactivated whole-cell vaccines (bacterins are routinely used in livestock and domestic animals, however, protection is serovar-restricted and short-term only. To overcome these limitations, efforts have focused on the development of recombinant vaccines, with partial success. Reverse vaccinology (RV has been successfully applied to many infectious diseases. A growing number of leptospiral genome sequences are now available in public databases, providing an opportunity to search for prospective vaccine antigens using RV. Several promising leptospiral antigens were identified using this approach, although only a few have been characterized and evaluated in animal models. In this review, we summarize the use of RV for leptospirosis and discuss the need for potential improvements for the successful development of a new vaccine towards reducing the burden of human and animal leptospirosis.

  6. Reverse Vaccinology: An Approach for Identifying Leptospiral Vaccine Candidates

    Science.gov (United States)

    Dellagostin, Odir A.; Grassmann, André A.; Rizzi, Caroline; Schuch, Rodrigo A.; Jorge, Sérgio; Oliveira, Thais L.; McBride, Alan J. A.; Hartwig, Daiane D.

    2017-01-01

    Leptospirosis is a major public health problem with an incidence of over one million human cases each year. It is a globally distributed, zoonotic disease and is associated with significant economic losses in farm animals. Leptospirosis is caused by pathogenic Leptospira spp. that can infect a wide range of domestic and wild animals. Given the inability to control the cycle of transmission among animals and humans, there is an urgent demand for a new vaccine. Inactivated whole-cell vaccines (bacterins) are routinely used in livestock and domestic animals, however, protection is serovar-restricted and short-term only. To overcome these limitations, efforts have focused on the development of recombinant vaccines, with partial success. Reverse vaccinology (RV) has been successfully applied to many infectious diseases. A growing number of leptospiral genome sequences are now available in public databases, providing an opportunity to search for prospective vaccine antigens using RV. Several promising leptospiral antigens were identified using this approach, although only a few have been characterized and evaluated in animal models. In this review, we summarize the use of RV for leptospirosis and discuss the need for potential improvements for the successful development of a new vaccine towards reducing the burden of human and animal leptospirosis. PMID:28098813

  7. Evaluation of the expression and protective potential of Leptospiral sphingomyelinases.

    Science.gov (United States)

    Carvalho, Eneas; Barbosa, Angela S; Gómez, Ricardo M; Oliveira, Maria L S; Romero, Eliete C; Gonçales, Amane P; Morais, Zenaide M; Vasconcellos, Sílvio A; Ho, Paulo L

    2010-02-01

    Leptospirosis is a zoonotic disease of global distribution, which affects both animals and humans. Pathogenic leptospires, the bacteria that cause this disease, require iron for their growth, and these spirochetes probably use their hemolysins, such as the sphingomyelinases, as a way to obtain this important nutrient from host red blood cells during infection. We expressed and purified the leptospiral sphingomyelinases Sph1, Sph2, Sph4, and SphH in a heterologous system. However, the recombinant proteins were not able to lyse sheep erythrocytes, despite having regular secondary structures. Transcripts for all sphingomyelinases tested were detected by RT-PCR analyses, but only Sph2 and SphH native proteins could be detected in Western blot assays using Leptospira whole extracts as well as in renal tubules of infected hamsters. Moreover, antibodies present in the serum of a human patient with laboratory-confirmed leptospirosis recognized Sph2, indicating that this sphingomyelinase is expressed and exposed to the immune system during infection in humans. However, in an animal challenge model, none of the sphingomyelinases tested conferred protection against leptospirosis.

  8. Shedding and seroprevalence of pathogenic Leptospira spp. in sheep and cattle at a New Zealand Abattoir.

    Science.gov (United States)

    Fang, F; Collins-Emerson, J M; Cullum, A; Heuer, C; Wilson, P R; Benschop, J

    2015-06-01

    A cross-sectional study was carried out on sheep and cattle slaughtered at a New Zealand abattoir from September to November 2010 to investigate the supplier-specific shedding rate, renal carriage rate and seroprevalence of leptospires. In the 2008/2009 season, this abattoir experienced three human leptospirosis cases from 20 staff, of which two were hospitalized. Urine, kidney and blood samples were collected from carcasses of 399 sheep (six suppliers, 17 slaughter lines) and 146 cattle (three suppliers, 22 slaughter lines). The urine and kidney samples were tested by quantitative real-time PCR (qPCR), while serum samples (from coagulated blood samples) were tested by microscopic agglutination test (MAT). In total, 27% (73/274; 95% CI: 18-37) of urine samples tested positive by qPCR. Species-specific shedding rates (prevalence of positive urine qPCR) were 31% (95% CI: 17-48) for sheep and 21% (95% CI: 14-30) for cattle. For 545 kidney samples tested, 145 were qPCR positive (27%; 95% CI: 17-39). The average prevalence of kidney qPCR positivity was 29% (95% CI: 17-45) for sheep and 21% (95% CI: 15-28) for cattle. Three hundred and thirty of 542 sampled sheep and cattle had antibodies against Leptospira borgpetersenii serovar Hardjobovis (Hardjobovis) and/or Leptospira interrogans serovar Pomona (Pomona), based on reciprocal MAT titre ≥1 : 48 (overall seroprevalence of 61%; 95% CI: 48-73). Seroprevalence was 57% (95% CI: 40-72) for sheep and 73% (95% CI: 59-83) for cattle. Among the seropositive animals, 41% (70/170; 95% CI: 30-54) were shedding (tested positive by urine qPCR) and 42% (137/330; 95% CI: 30-54) had renal carriage (tested positive by kidney qPCR). Some risk management options for abattoirs or farms to prevent human leptospirosis infections include vaccination of maintenance hosts, the use of personal protective equipment, and the application of urine qPCR to detect shedding status of stock as surveillance and as an alert.

  9. An Emerging Pulmonary Haemorrhagic Syndrome in Dogs: Similar to the Human Leptospiral Pulmonary Haemorrhagic Syndrome?

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    R. Klopfleisch

    2010-01-01

    Full Text Available Severe pulmonary haemorrhage is a rare necropsy finding in dogs but the leptospiral pulmonary haemorrhagic syndrome (LPHS is a well recognized disease in humans. Here we report a pulmonary haemorrhagic syndrome in dogs that closely resembles the human disease. All 15 dogs had massive, pulmonary haemorrhage affecting all lung lobes while haemorrhage in other organs was minimal. Histologically, pulmonary lesions were characterized by acute, alveolar haemorrhage without identifiable vascular lesions. Seven dogs had mild alveolar wall necrosis with hyaline membranes and minimal intraalveolar fibrin. In addition, eight dogs had acute renal tubular necrosis. Six dogs had a clinical diagnosis of leptospirosis based on renal and hepatic failure, positive microscopic agglutination test (MAT and/or positive blood/urine Leptospira-specific PCR. Leptospira could not be cultured post mortem from the lungs or kidneys. However, Leptospira-specific PCR was positive in lung, liver or kidneys of three dogs. In summary, a novel pulmonary haemorrhagic syndrome was identified in dogs but the mechanism of the massive pulmonary erythrocyte extravasation remains elusive. The lack of a consistent post mortem identification of Leptospira spp. in dogs with pulmonary haemorrhage raise questions as to whether additional factors besides Leptospira may cause this as yet unrecognized entity in dogs.

  10. Multiplex PCR-based detection of Leptospira in environmental water samples obtained from a slum settlement

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    Juliana Magalhães Vital-Brazil

    2010-05-01

    Full Text Available The aim of this study was to apply a molecular protocol to detect leptospiral DNA in environmental water samples. The study was carried out in a peri-urban settlement in Petrópolis, state of Rio de Janeiro. A multiplex PCR method employing the primers LipL32 and 16SrRNA was used. Three out of 100 analysed samples were positive in the multiplex PCR, two were considered to have saprophytic leptospires and one had pathogenic leptospires. The results obtained supported the idea that multiplex PCR can be used to detect Leptospira spp in water samples. This method was also able to differentiate between saprophytic and pathogenic leptospires and was able to do so much more easily than conventional methodologies.

  11. Sorovares de leptospiras predominantes em exames sorológicos de bubalinos, ovinos, caprinos, eqüinos, suínos e cães de diversos estados brasileiros Most frequent serovars of leptospires in serological tests of buffaloes, sheeps, goats, horses, swines and dogs from several brazilian states

    Directory of Open Access Journals (Sweden)

    Andrea Cecília Mercaldi Favero

    2002-08-01

    icterohaemorrhagiae em MG, pomona no RS, pomona e icterohaemorrhagiae em PE e RJ, autumnalis no CE e icterohaemorrhagiae em GO, PR, SC e SP.From 1984 to 1997 15.558 sorologic tests to leptospirosis were performed (MAT with 24 leptospires serovars in 284 sheeps, 879 boffaloes, 983 dogs, 1.941 goats, 2.903 horses and 8.568 swines. The distribuition of animals examined by species and state were: sheeps - SP (100%; buffaloes - SP (100%; dogs - SP (80.7%, RS (0.10%, SC (0.10% and PI (19.0%; goats - SP (33.1%, PB (63.7% and CE (3.2%; horses - SP (79.3%, RS (9.98%, SC (0.62%, PR (2.5%, RJ (0.17%, MG (1.96%, MT (3.99%, PB (1.3% and PI (0.03%; swines - SP (61.91%, RS (0.3%, SC (5.95%, PR (3.67%, RJ (0.88%, MG (24.38%, GO (1.12%, SE (0.2%, PE (0.90%, CE (0.34% and MA (0.1%. From the sheeps tested, 54.5% were examined between 1996 and 97. 33.3% between 1989 and 1990 and 12.2% in the other years; buffaloes - 21.7% from 1984 to 95 and 78.83% between 1996 and 97; dogs - 16.91% from 1984 to 92 and 83.09% from 1993 to 97; goats - 6.97% from 1984 to 91 and 93.09% from 1992 to 97, althought 49% were concerning to 1992; horses - 18.1% from 84 to 90 and 81.9% from 1991 to 97; swines - 61.16% concerning 1990, 91, 95 and 96. The proportion of reactors to at least one leptospira serovar presented the following average and most frequent serovars: sheeps - 0.70% and icterohaemorrhagiae like most frequent serovar; buffaloes - 43.7% and serovars hardjo and pomona; dogs - 17.7% and serovar icterohaemorrhagiae in SP and pyrogenes in PI; goats - 4.17% and icterohaemorrhagiae and grippotyphosa in CE, icterohaemorrhagiae in PB and pyrogenes in SP; horses - 29% and serovar icterohaemorrhagiae in PR, SC, SP, RJ e MG, grippotyphosa in MT, pyrogenes in PB and patoc in RS; swines -24.46% and serovar grippotyphosa and icterohaemorrhagiae in MG, pomona in RS, pomona and icterohaemorrhagiae in PE and RJ, autumnalis in CE and icterohaemorrhagiae in GO, PR, SC e SP.

  12. Responses of murine and human macrophages to leptospiral infection: a study using comparative array analysis.

    Directory of Open Access Journals (Sweden)

    Feng Xue

    Full Text Available Leptospirosis is a re-emerging tropical infectious disease caused by pathogenic Leptospira spp. The different host innate immune responses are partially related to the different severities of leptospirosis. In this study, we employed transcriptomics and cytokine arrays to comparatively calculate the responses of murine peritoneal macrophages (MPMs and human peripheral blood monocytes (HBMs to leptospiral infection. We uncovered a series of different expression profiles of these two immune cells. The percentages of regulated genes in several biological processes of MPMs, such as antigen processing and presentation, membrane potential regulation, and the innate immune response, etc., were much greater than those of HBMs (>2-fold. In MPMs and HBMs, the caspase-8 and Fas-associated protein with death domain (FADD-like apoptosis regulator genes were significantly up-regulated, which supported previous results that the caspase-8 and caspase-3 pathways play an important role in macrophage apoptosis during leptospiral infection. In addition, the key component of the complement pathway, C3, was only up-regulated in MPMs. Furthermore, several cytokines, e.g. interleukin 10 (IL-10 and tumor necrosis factor alpha (TNF-alpha, were differentially expressed at both mRNA and protein levels in MPMs and HBMs. Some of the differential expressions were proved to be pathogenic Leptospira-specific regulations at mRNA level or protein level. Though it is still unclear why some animals are resistant and others are susceptible to leptospiral infection, this comparative study based on transcriptomics and cytokine arrays partially uncovered the differences of murine resistance and human susceptibility to leptospirosis. Taken together, these findings will facilitate further molecular studies on the innate immune response to leptospiral infection.

  13. Development of a real-time PCR for the detection of pathogenic Leptospira spp. in California sea lions

    Science.gov (United States)

    Rapid detection of pathogenic Leptospira spp. in marine mammals is challenging: microbiological culture can take 3-6 months and has low sensitivity, immunohistochemical staining of kidney to detect leptospires is invasive and time consuming, and serological methods, such as the microscopic agglutina...

  14. Molecular characterization of the first leptospires isolated from goats in Brazil

    Science.gov (United States)

    Lilenbaum, Walter; Kremer, Frederico; Ristow, Paula; Dellagostin, Odir; Bourhy, Pascale; Hartskeerl, Rudy; Vasconcellos, Silvio

    2014-01-01

    Two Leptospira sp. isolates were obtained by the first time from goats in Brazil and characterized by sequencing rrs, rpoB and secY genes, PFGE and typing with monoclonal antibodies. Both isolates are identical and belong to Leptospira santarosai. Analysis of the rrs and the rpoB genes sequences revealed 100% identity between the goat isolates and the Bananal reference strain. When secY sequences of the two isolates were compared to each other, it was observed that they had identical sequences. However, when compared to that of the Bananal reference strain, there were 15 mismatches along the 549 bp secY sequence. In conclusion, molecular methods are increasingly useful for the characterization of leptospires and allowed to identify those isolates of caprine origin as closely related but not identical to serovar Bananal, and constitute a new type named Carioca. PMID:25763063

  15. Molecular characterization of the first leptospires isolated from goats in Brazil

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    Walter Lilenbaum

    2014-12-01

    Full Text Available Two Leptospira sp. isolates were obtained by the first time from goats in Brazil and characterized by sequencing rrs, rpoB and secY genes, PFGE and typing with monoclonal antibodies. Both isolates are identical and belong to Leptospira santarosai. Analysis of the rrs and the rpoB genes sequences revealed 100% identity between the goat isolates and the Bananal reference strain. When secY sequences of the two isolates were compared to each other, it was observed that they had identical sequences. However, when compared to that of the Bananal reference strain, there were 15 mismatches along the 549 bp secY sequence. In conclusion, molecular methods are increasingly useful for the characterization of leptospires and allowed to identify those isolates of caprine origin as closely related but not identical to serovar Bananal, and constitute a new type named Carioca.

  16. Detection of Leptospira spp. in wildlife reservoir hosts in Ontario through comparison of immunohistochemical and polymerase chain reaction genotyping methods.

    Science.gov (United States)

    Shearer, Karen E; Harte, Michael J; Ojkic, Davor; Delay, Josepha; Campbell, Douglas

    2014-03-01

    A total of 460 kidney samples from wildlife (beavers, coyotes, deer, foxes, opossums, otters, raccoons, skunks) were obtained from road-kill and hunter/trapper donations in Ontario between January 2010 and November 2012. The objectives of the study were to detect Leptospira spp. by immunohistochemistry and polymerase chain reaction (PCR), to map presence of leptospires in wildlife relative to livestock and human populations, and to characterize positive samples by sequencing and comparison to leptospires known to affect domestic animals and humans. The proportion of samples that tested positive ranged from 0% to 42%, with the highest rates in skunks and raccoons. Leptospira spp. were present in kidneys of wildlife across Ontario, particularly in areas of high human density, and areas in which livestock populations are abundant. The PCR was too weak in most samples to permit genotyping and examination of the relationship between the leptospires found in this study and those affecting domestic animals and humans.

  17. Overlooked Risk for Chronic Kidney Disease after Leptospiral Infection: A Population-Based Survey and Epidemiological Cohort Evidence.

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    Huang-Yu Yang

    Full Text Available Leptospirosis is the most widespread zoonosis. Chronic human infection and asymptomatic colonization have been reported. However, renal involvement in those with leptospira chronic exposure remains undetermined.In 2007, a multistage sampling survey for chronic kidney disease (CKD was conducted in a southern county of Taiwan, an area with a high prevalence of dialysis. Additionally, an independent cohort of 88 participants from a leptospira-endemic town was followed for two years after a flooding in 2009. Risks of CKD, stages of CKD, associated risk factors as well as kidney injury markers were compared among adults with anti-leptospira antibody as defined by titers of microscopic agglutination test (MAT. Of 3045 survey participants, the individuals with previous leptospira exposure disclosed a lower level of eGFR (98.3 ± 0.4 vs 100.8 ± 0.6 ml/min per 1.73 m2, P < 0.001 and a higher percentage of CKD, particularly at stage 3a-5 (14.4% vs 8.5%, than those without leptospira exposure. Multivariable linear regression analyses indicated the association of leptospiral infection and lower eGFR (95% CI -4.15 to -1.93, P < 0.001. In a leptospiral endemic town, subjects with a MAT titer ≥ 400 showed a decreased eGFR and higher urinary kidney injury molecule-1 creatinine ratio (KIM1/Cr level as compared with those having lower titers of MAT (P < 0.05. Furthermore, two participants with persistently high MAT titers had positive urine leptospira DNA and deteriorating renal function.Our data are the first to show that chronic human exposure of leptospirosis is associated significantly with prevalence and severity of CKD and may lead to deterioration of renal function. This study also shed light on the search of underlying factors in areas experiencing CKD of unknown aetiology (CKDu such as Mesoamerican Nephropathy.

  18. Decay-accelerating factor 1 deficiency exacerbates leptospiral-induced murine chronic nephritis and renal fibrosis.

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    María F Ferrer

    Full Text Available Leptospirosis is a global zoonosis caused by pathogenic Leptospira, which can colonize the proximal renal tubules and persist for long periods in the kidneys of infected hosts. Here, we characterized the infection of C57BL/6J wild-type and Daf1-/- mice, which have an enhanced host response, with a virulent Leptospira interrogans strain at 14 days post-infection, its persistence in the kidney, and its link to kidney fibrosis at 90 days post-infection. We found that Leptospira interrogans can induce acute moderate nephritis in wild-type mice and is able to persist in some animals, inducing fibrosis in the absence of mortality. In contrast, Daf1-/- mice showed acute mortality, with a higher bacterial burden. At the chronic stage, Daf1-/- mice showed greater inflammation and fibrosis than at 14 days post-infection and higher levels at all times than the wild-type counterpart. Compared with uninfected mice, infected wild-type mice showed higher levels of IL-4, IL-10 and IL-13, with similar levels of α-smooth muscle actin, galectin-3, TGF-β1, IL-17, IFN-γ, and lower IL-12 levels at 90 days post-infection. In contrast, fibrosis in Daf1-/- mice was accompanied by high expression of α-smooth muscle actin, galectin-3, IL-10, IL-13, and IFN-γ, similar levels of TGF-β1, IL-12, and IL-17 and lower IL-4 levels. This study demonstrates the link between Leptospira-induced murine chronic nephritis with renal fibrosis and shows a protective role of Daf1.

  19. Decay-accelerating factor 1 deficiency exacerbates leptospiral-induced murine chronic nephritis and renal fibrosis.

    Science.gov (United States)

    Ferrer, María F; Scharrig, Emilia; Alberdi, Lucrecia; Cedola, Maia; Pretre, Gabriela; Drut, Ricardo; Song, Wen-Chao; Gomez, Ricardo M

    2014-01-01

    Leptospirosis is a global zoonosis caused by pathogenic Leptospira, which can colonize the proximal renal tubules and persist for long periods in the kidneys of infected hosts. Here, we characterized the infection of C57BL/6J wild-type and Daf1-/- mice, which have an enhanced host response, with a virulent Leptospira interrogans strain at 14 days post-infection, its persistence in the kidney, and its link to kidney fibrosis at 90 days post-infection. We found that Leptospira interrogans can induce acute moderate nephritis in wild-type mice and is able to persist in some animals, inducing fibrosis in the absence of mortality. In contrast, Daf1-/- mice showed acute mortality, with a higher bacterial burden. At the chronic stage, Daf1-/- mice showed greater inflammation and fibrosis than at 14 days post-infection and higher levels at all times than the wild-type counterpart. Compared with uninfected mice, infected wild-type mice showed higher levels of IL-4, IL-10 and IL-13, with similar levels of α-smooth muscle actin, galectin-3, TGF-β1, IL-17, IFN-γ, and lower IL-12 levels at 90 days post-infection. In contrast, fibrosis in Daf1-/- mice was accompanied by high expression of α-smooth muscle actin, galectin-3, IL-10, IL-13, and IFN-γ, similar levels of TGF-β1, IL-12, and IL-17 and lower IL-4 levels. This study demonstrates the link between Leptospira-induced murine chronic nephritis with renal fibrosis and shows a protective role of Daf1.

  20. Hedgehogs and Mustelid Species: Major Carriers of Pathogenic Leptospira, a Survey in 28 Animal Species in France (20122015)

    Science.gov (United States)

    Raton, Vincent; Zilber, Anne-Laure; Gasqui, Patrick; Faure, Eva; Baurier, Florence; Vourc’h, Gwenaël; Kodjo, Angeli; Combes, Benoît

    2016-01-01

    Human leptospirosis is a zoonotic and potentially fatal disease that has increasingly been reported in both developing and developed countries, including France. However, our understanding of the basic aspects of the epidemiology of this disease, including the source of Leptospira serogroup Australis infections in humans and domestic animals, remains incomplete. We investigated the genetic diversity of Leptospira in 28 species of wildlife other than rats using variable number tandem repeat (VNTR) and multispacer sequence typing (MST). The DNA of pathogenic Leptospira was detected in the kidney tissues of 201 individuals out of 3,738 tested individuals. A wide diversity, including 50 VNTR profiles and 8 MST profiles, was observed. Hedgehogs and mustelid species had the highest risk of being infected (logistic regression, OR = 66.8, CI95% = 30.9–144 and OR = 16.7, CI95% = 8.7–31.8, respectively). Almost all genetic profiles obtained from the hedgehogs were related to Leptospira interrogans Australis, suggesting the latter as a host-adapted bacterium, whereas mustelid species were infected by various genotypes, suggesting their interaction with Leptospira was different. By providing an inventory of the circulating strains of Leptospira and by pointing to hedgehogs as a potential reservoir of L. interrogans Australis, our study advances current knowledge on Leptospira animal carriers, and this information could serve to enhance epidemiological investigations in the future. PMID:27680672

  1. 问号钩端螺旋体毒力相关蛋白InvA转录和表达特征的研究%Transcription and expression characteristics of Leptospira virulence-associated protein InvA

    Institute of Scientific and Technical Information of China (English)

    罗依惠; 陈铭; 李立伟; 钱景; 严杰

    2009-01-01

    objective To determine the existence of virulence-associated invA gene in different genospeeies of Leptospira interrogans reference strains in China.and to understand the alterations of invA gene transcription and expression of L.interrogans strain Lai before or after infecting cells.Methods PCR was applied to detect the invA gene of four L.interrogans strains belonging to four different genospecies and L.biflexa strain Patoc Ⅰ.The entire invA genes from the L.interrogans strains were cloned and then sequenced.The prokaryotic expression system of invA gene of L.interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai was constructed.Using Ni-NTA affinity chromatography,the target recombinant protein rInvA was extracted and purified.Rabbits were immunized with rInvA to obtain antiserum and the titer of antiserum was determined by immunodiffusion test.A model of L interrogans strain Lai infecting human embryo kidney cell line HEK293 was established to detect the alterations of invA gene transcription and expression of the leptospiral strain before or after infecting the host cells by real-time fluorescent quantitative RTPCR and western blot assay.Results All the four tested L.interrogans strains had invA gene whereas L.biflexa strain Patoc Ⅰ not.The similarity of nucleotide and putative amino acid sequences of invA genes from the four L.interrogans strains belonging four different genospecies were 99.33%-100%and 98.66%-100%,respectively.The constructed prokaryotic expression system could efficiently express rInvA and the immunodiffusion titer of rabbit anti-rInvA serum was 1:16.After L.interrogans strain Lai infecting HEK293 cells for 30 min or above,the microbe could adhere the surface of the cells.On the 30 min after the infection,the mRNA level of invA gene of L.interrogans strain Lai was remarkably upregulated,and on the 45 min after infection the mRNA level presented a peak value and then graduated decreased.On the 45 min or 60 min after L.interrogans

  2. Conservation of the S10-spc-alpha locus within otherwise highly plastic genomes provides phylogenetic insight into the genus Leptospira.

    Science.gov (United States)

    Victoria, Berta; Ahmed, Ahmed; Zuerner, Richard L; Ahmed, Niyaz; Bulach, Dieter M; Quinteiro, Javier; Hartskeerl, Rudy A

    2008-07-16

    S10-spc-alpha is a 17.5 kb cluster of 32 genes encoding ribosomal proteins. This locus has an unusual composition and organization in Leptospira interrogans. We demonstrate the highly conserved nature of this region among diverse Leptospira and show its utility as a phylogenetically informative region. Comparative analyses were performed by PCR using primer sets covering the whole locus. Correctly sized fragments were obtained by PCR from all L. interrogans strains tested for each primer set indicating that this locus is well conserved in this species. Few differences were detected in amplification profiles between different pathogenic species, indicating that the S10-spc-alpha locus is conserved among pathogenic Leptospira. In contrast, PCR analysis of this locus using DNA from saprophytic Leptospira species and species with an intermediate pathogenic capacity generated varied results. Sequence alignment of the S10-spc-alpha locus from two pathogenic species, L. interrogans and L. borgpetersenii, with the corresponding locus from the saprophyte L. biflexa serovar Patoc showed that genetic organization of this locus is well conserved within Leptospira. Multilocus sequence typing (MLST) of four conserved regions resulted in the construction of well-defined phylogenetic trees that help resolve questions about the interrelationships of pathogenic Leptospira. Based on the results of secY sequence analysis, we found that reliable species identification of pathogenic Leptospira is possible by comparative analysis of a 245 bp region commonly used as a target for diagnostic PCR for leptospirosis. Comparative analysis of Leptospira strains revealed that strain H6 previously classified as L. inadai actually belongs to the pathogenic species L. interrogans and that L. meyeri strain ICF phylogenetically co-localized with the pathogenic clusters. These findings demonstrate that the S10-spc-alpha locus is highly conserved throughout the genus and may be more useful in comparing

  3. Household transmission of leptospira infection in urban slum communities.

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    Elves A P Maciel

    Full Text Available BACKGROUND: Leptospirosis, a spirochaetal zoonotic disease, is the cause of epidemics associated with high mortality in urban slum communities. Infection with pathogenic Leptospira occurs during environmental exposures and is traditionally associated with occupational risk activities. However, slum inhabitants reside in close proximity to environmental sources of contamination, suggesting that transmission during urban epidemics occurs in the household environment. METHODS AND FINDINGS: A survey was performed to determine whether Leptospira infection clustered within households located in slum communities in the city of Salvador, Brazil. Hospital-based surveillance identified 89 confirmed cases of leptospirosis during an outbreak. Serum samples were obtained from members of 22 households with index cases of leptospirosis and 52 control households located in the same slum communities. The presence of anti-Leptospira agglutinating antibodies was used as a marker for previous infection. In households with index cases, 22 (30% of 74 members had anti-Leptospira antibodies, whereas 16 (8% of 195 members from control households had anti-Leptospira antibodies. Highest titres were directed against L. interrogans serovars of the Icterohaemorrhagiae serogroup in 95% and 100% of the subjects with agglutinating antibodies from case and control households, respectively. Residence in a household with an index case of leptospirosis was associated with increased risk (OR 5.29, 95% CI 2.13-13.12 of having had a Leptospira infection. Increased infection risk was found for all age groups who resided in a household with an index case, including children <15 years of age (P = 0.008. CONCLUSIONS: This study identified significant household clustering of Leptospira infection in slum communities where recurrent epidemics of leptospirosis occur. The findings support the hypothesis that the household environment is an important transmission determinant in the urban slum

  4. Single dosage of doxycycline for prophylaxis against leptospiral infection and leptospirosis during urban flooding in southern Thailand: a non-randomized controlled trial.

    Science.gov (United States)

    Chusri, Sarunyou; McNeil, Edward B; Hortiwakul, Thanaporn; Charernmak, Boonsri; Sritrairatchai, Somporn; Santimaleeworagun, Wichai; Pattharachayakul, Sutthiporn; Suksanan, Paritasana; Thaisomboonsuk, Butsaya; Jarman, Richard G

    2014-11-01

    This study was conducted to investigate the protective efficacy of a single dosage of 200 mg doxycycline against leptospiral infection and leptospirosis and associated risk factors among residents exposed to flooding in southern Thailand. Of 641 participants, 600 received doxycycline while 41 did not. Twenty two participants were infected with Leptospira and six developed leptospirosis. Having a laceration wound was significantly associated with leptospiral infection (odds ratio [OR] = 37.20; P doxycycline and five who did not, were infected with Leptospira, resulting a protective efficacy of 76.8% (95% confidence interval [CI] = 34.3%-92.0%). Four who received doxycycline and two who did not, developed leptospirosis, resulting a protective efficacy of 86.3% (CI = -9.8%-98.2%). Among the participants with laceration wound, the protective efficacy for leptospiral infection was 92.0% (CI = 81.2%-96.6%) and for leptospirosis was 95.6% (CI = 78.2%-99.3%). Among the participants exposed to flood water less than or equal to 3 h per day, the protective efficacy for leptospiral infection was 89.2% (95% CI 63.6%-96.67%). A single dosage of 200 mg doxycycline for prophylaxis might be effective for preventing leptospirosis among flood victims with laceration wound after recent flood exposure.

  5. Multilocus sequence typing (MLST): markers for the traceability of pathogenic Leptospira strains.

    Science.gov (United States)

    Ahmed, Ahmed; Ferreira, Ana S; Hartskeerl, Rudy A

    2015-01-01

    Leptospirosis is a major zoonosis with worldwide distribution. Conventional serological typing is arduous and time consuming. Genotyping is increasingly applied for the typing and identification of leptospires and contributes to genetic and virulence divergence and molecular epidemiological characteristics such as host versus leptospires population interactions and dynamics. Presently, multilocus sequence typing (MLST) is the most robust approach. In this chapter, we describe the practical steps of two major multilocus sequence typing methods for leptospires. The first method (denoted as the 6 L scheme) is based on genotyping by phylogeny using concatenated sequences derived from six loci, including genes that encode outer membrane proteins and rrs and can be used for typing pathogenic species and strains of intermediate species. The second method (referred to as the 7 L scheme) uses seven loci on housekeeping genes and allows the analysis of seven major Leptospira pathogenic species. The 7 L scheme is web based and includes the option to analyze sequence types (STs).

  6. High prevalence of pathogenicLeptospira in wild and domesticated animals in an endemic area of China

    Institute of Scientific and Technical Information of China (English)

    Wang Yalin; Zeng Lingbing; Yang Hongliang; Xu Jianmin; Zhang Xiangyan; Guo Xiaokui; Pal Utpal; Qin Jinhong

    2011-01-01

    Objective:To assess the prevalence ofLeptospira detected in wildlife and domesticated animals in Jiangxi Province, China, in2009.Methods:Urine samples from 28 buffaloes and kidney samples from50 pigs,50 dogs and38 rats were collected from Fuliang and Shangrao County, Jiangxi Province, China, in October2009. Polymerase chain reaction(PCR) and culture analyses were used to detectLeptospira. The cultured isolates were typed using the microscopic agglutination test (MAT).Results:The results showed that rats potentially serve as the main reservoir of leptospiral infection, followed by dogs. Although16% of rats (6/38) were positive using culture analysis, PCR analysis using the diagnostic primersG1/G2 and B64I/B64II or lipL32 showed identification as50% and24%, respectively, of the rat samples as positive for the presence of leptospiralDNA.Conclusions:PCR-based detection of leptospiralDNA in infected kidney tissues of reservoirs is more efficient when usingG1/G2 primers thanlipL32 primers. However, the latter primers have a potential application for detection in urine samples. The alarmingly high prevalence of leptospiralDNAin the wild rat population near human habitation underscores the utility of routineLeptospira surveillance, preferably usingPCR methods, which are more sensitive than traditional culture-based methods.

  7. The Characteristics of Ubiquitous and Unique Leptospira Strains from the Collection of Russian Centre for Leptospirosis

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    Olga L. Voronina

    2014-01-01

    Full Text Available Background and Aim. Leptospira, the causal agent of leptospirosis, has been isolated from the environment, patients, and wide spectrum of animals in Russia. However, the genetic diversity of Leptospira in natural and anthropurgic foci was not clearly defined. Methods. The recent MLST scheme was used for the analysis of seven pathogenic species. 454 pyrosequencing technology was the base of the whole genome sequencing (WGS. Results. The most wide spread and prevalent Leptospira species in Russia were L. interrogans, L. kirschneri, and L. borgpetersenii. Five STs, common for Russian strains: 37, 17, 199, 110, and 146, were identified as having a longtime and ubiquitous distribution in various geographic areas. Unexpected properties were revealed for the environmental Leptospira strain Bairam-Ali. WGS of this strain genome suggested that it combined the features of the pathogenic and nonpathogenic strains and may be a reservoir of the natural resistance genes. Results of the comparative analysis of rrs and rpoB genes and MLST loci for different Leptospira species strains and phenotypic and serological properties of the strain Bairam-Ali suggested that it represented separate Leptospira species. Conclusions. Thus, the natural and anthropurgic foci supported ubiquitous Leptospira species and the pool of genes important for bacterial adaptivity to various conditions.

  8. The Characteristics of Ubiquitous and Unique Leptospira Strains from the Collection of Russian Centre for Leptospirosis

    Science.gov (United States)

    Voronina, Olga L.; Kunda, Marina S.; Aksenova, Ekaterina I.; Ryzhova, Natalia N.; Semenov, Andrey N.; Petrov, Evgeny M.; Didenko, Lubov V.; Lunin, Vladimir G.; Ananyina, Yuliya V.; Gintsburg, Alexandr L.

    2014-01-01

    Background and Aim. Leptospira, the causal agent of leptospirosis, has been isolated from the environment, patients, and wide spectrum of animals in Russia. However, the genetic diversity of Leptospira in natural and anthropurgic foci was not clearly defined. Methods. The recent MLST scheme was used for the analysis of seven pathogenic species. 454 pyrosequencing technology was the base of the whole genome sequencing (WGS). Results. The most wide spread and prevalent Leptospira species in Russia were L. interrogans, L. kirschneri, and L. borgpetersenii. Five STs, common for Russian strains: 37, 17, 199, 110, and 146, were identified as having a longtime and ubiquitous distribution in various geographic areas. Unexpected properties were revealed for the environmental Leptospira strain Bairam-Ali. WGS of this strain genome suggested that it combined the features of the pathogenic and nonpathogenic strains and may be a reservoir of the natural resistance genes. Results of the comparative analysis of rrs and rpoB genes and MLST loci for different Leptospira species strains and phenotypic and serological properties of the strain Bairam-Ali suggested that it represented separate Leptospira species. Conclusions. Thus, the natural and anthropurgic foci supported ubiquitous Leptospira species and the pool of genes important for bacterial adaptivity to various conditions. PMID:25276806

  9. Detection of pathogenic Leptospira spp. By polymerase chain reaction reaction (PCR targeting ligB gene

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    Fariba Fotohi

    2014-10-01

    Full Text Available Background: Leptospirosis is an emerging infectious disease and is considered to be the most widespread zoonotic disease in the world. LigB is an immunogenic outer membrane protein. The leptospiral ligB gene expressed only in pathogenic Leptospira spp. The aim of this study was molecular diagnosis of pathogen Leptospires by PCR based on ligB gene. Materials and Methods: Five pathogenic Leptospires: L. canicola, L. grippotyphosa, L. pomona, L. icterohaemorrhagiae, L. serjoe hardjo and saprophytic L. biflexa were used in this study. The bacteria were inoculated into the selective culture medium and extraction of the genomic DNA was performed by standard Phenol-Chlorophorm method. The specific primers for proliferation of ligB gene were designed. The specificity and sensitivity of PCR method was evaluated. Results: PCR product was 1041bp which indicated proliferation of ligB gene which was supported using electrophoresis. The PCR based on ligB gene detected all pathogenic reference serovars of Leptospira spp. tested. No PCR products were amplified from the non-pathogenic L. biflexa. Conclusion: Considering the spread of Leptosperosis in moderate and hot areas which have high rate of fall, a proper molecular diagnostic test with high specificity and sensitivity such as PCR is essential. PCR assay with high specificity and sensitivity may prove to be a rapid method for diagnosing acute leptospirosis. The results suggested that the PCR based on ligB gene can be used for detection of pathogenic leptospires.

  10. Soroprevalência da infecção leptospiral em capivaras (Hydrochoerus hydrochaeris abatidas em um frigorífico do Rio Grande do Sul Seroprevalence of leptospiral infection in capybaras (Hydrochoerus hydrochaeris in a slaughterhouse of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Éverton F. Silva

    2009-02-01

    Full Text Available Capivaras (Hydrochoerus hydrochaeris são roedores selvagens do continente americano com crescente importância comercial como fonte alternativa de carne para o consumo humano. Nessa espécie, os estudos sobre a soroprevalência da infecção leptospiral são escassos e restritos aos espécimes de vida livre. Relatamos aqui reações positivas para anticorpos aglutinantes anti-leptospiras em 27,3% (6/22 das capivaras abatidas em um frigorífico do Rio Grande do Sul. Os níveis mais altos de anticorpos sugerem infecção pelo sorogrupo Australis devido à reação para uma cepa de referência do sorovar Bratislava e para um isolado canino local do sorovar Australis, caracterizado como Leptospira noguchii. Esses resultados ressaltam que considerável parcela de capivaras criadas em cativeiro podem funcionar como reservatório de leptospiras patogênicas e chamam atenção para o risco ocupacional dos trabalhos que envolvem a criação e o abate dessa espécie animal.Capybaras (Hydrochoerus hydrochaeris are wild rodents from the American Continent with increasing importance as a commercial alternative source of meat for human consumption. Studies on seroprevalence for leptospiral infection are scarce and restricted to free living capybaras. We report detection of agglutinating antibodies against leptospires in 27% (6/22 of all animals in a slaughterhouse from Rio Grande do Sul. The highest antibody titers predicted Australis as the infecting serogroup due to reactions against a reference strain of serovar Bratislava and a canine local isolate of serovar Australis, characterized as Leptospira noguchii. The data presented in this report highlight that a considerable fraction of capybaras in captivity may behave as reservoir for pathogenic leptospires emphasizing the occupational risk of those who deal with animal farming and slaughter.

  11. Phylogenetic and genetic diversity analysis in Leptospira species based on the sequence homology pattern of 16S rRNA gene

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    Pasupuleti Sreenivasa Rao

    2013-08-01

    Full Text Available Leptospirosis is a bacterial zoonosis, caused by pathogenic spirochete which belongs to the genus Leptospira. It exists in diverse ecological habitats and affects almost all the mammals including humans. Several online databases like NCBI etc will provide the complete genomic sequence data of various Leptospira species. However, the Phylogenetic and genetic diversity Analysis in Leptospira species based on 16S rRNA gene has not studied in detail. Therefore the present study was conducted. Sequences of various species related to genus Leptospira obtained from the NCBI database etc and aligned (CLUSTAL_X. Two Phylogenetic trees were constructed (MEGA-5 in which the first one is related to various serovars of L. interrogans and the other is related to various species of Leptospira. The Phylogenetic trees revealed the relationship and genetic diversity of various serovars of L. interrogans and the other Leptospira species, with their nearest phylogenetic relatives. In the first tree, two major clades were observed which were named as A and B, whereas in the second tree, three major clades were observed and named as A, B and C respectively. Aquifex pyrophilus strain has been used for out grouping in both the trees. The genetic distance between the species in the phylogenetic tree is presented by a bar which represents 0.5 nucleotide substitutions per alignment position in the 16S rRNA gene sequence among the various serovars of L. interrogans while 0.05 nucleotide substitutions in case of various species related to the genus Leptospira. Thus, the findings from the above study confirm that the genus Leptospira exhibits genetic diversity in the 16S rRNA gene. [Int J Res Med Sci 2013; 1(4.000: 369-377

  12. Serological prevalence of leptospiral infection in wild rats at the National Service Training Centres in Kelantan and Terengganu.

    Science.gov (United States)

    Mohamed-Hassan, S N; Bahaman, A R; Mutalib, A R; Khairani-Bejo, S

    2010-04-01

    One hundred and sixty eight rats were trapped from the National Service Training Centres (NSTC) in Kelantan and Terengganu from October 2008 to May 2009. Microscopic agglutination test (MAT) was performed to detect the presence of agglutinating antibodies to Leptospira among the rats caught. All the MAT positive rats were identified as Rattus tiomanicus. In Kelantan, 17.3 % (14/81) of the rats had leptospiral antibodies to serovars Icterohaemorrhagiae (12.3%), Canicola (2.5%), Ballum (1.2%), and Pyrogenes (1.2%). In Terengganu, 18.4% (16/87) of the rats had antibodies to serovars Icterohaemorrhagiae (15%), Canicola (1.1%), Pyrogenes (1.1%) and Hebdomadis (1.1%). This study indicated that Leptospira serovars were prevalent in the rat population in the study areas and could be a source of infection to humans. Therefore, control of the rat population in all NSTC is critical to prevent outbreaks of leptospirosis amongst the NSTC trainees.

  13. A field-study on Leptospira seroprevalence in dairy cows in four geographical areas in Sweden

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    Artursson Karin

    2011-10-01

    Full Text Available Abstract Background Dairy cattle were used as sentinels for the presence of Leptospira infection in Swedish livestock in four regions contrasting in precipitation and temperature during the summer time. The aim of the study was to estimate the prevalence of five serovars of Leptospira of low pathogenicity in dairy cattle in these four regions. Findings Around 150 blood samples were collected from five dairy farms from each region, making 610 samples in total, during December 2009. The samples were screened for L. kirschneri sv Grippotyphosa, L. interrogans sv Icterohaemorrhagiae, L. interrogans sv Canicola, L. borgpetersenii sv Sejroe and one domestic strain similar to sv Sejroe, called strain Mouse 2A using the Microscopic Agglutination Test. Six animals (1% were seropositive for the strain Mouse 2A. Four of the positive samples were from the south-west region which also was the region with highest precipitation. There were no positive samples to any of the other serovars studied. Conclusions The present data indicate that there is a low seroprevalence of Leptospira in Swedish dairy cows. These findings can be used as baseline data to investigate the effects of, for instance, climatic change or alterations in wildlife reservoir populations on the seroprevalence of Leptospira in the future.

  14. Leptospira spp. and Toxoplasma gondii antibodies in vampire bats (Desmodus rotundus in Botucatu region, SP, Brazil

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    CB Zetun

    2009-01-01

    Full Text Available The destruction of natural ecosystems has caused several problems to humans and other animals; herein we investigate the close relationship among vampire bats, humans and domestic animals. Toxoplasma gondii and Leptospira spp. infections are two worldwide zoonoses that provoke serious damage to animals. To determine the prevalence of bats seropositive for toxoplasmosis and leptospirosis in the Botucatu region, 204 serum samples of vampire bats (Desmodus rotundus were tested for T. gondii antibodies by modified agglutination test (MAT-t and for Leptospira spp. by microscopic agglutination test (MAT-l. No animal was tested positive for T. gondii while leptospiral positivity was 7.8% for Pyrogenes, Shermani and Javanica serovars, with titers varying from 100 to 1,600. Thus, it was verified that D. rotundus does not play a relevant role in toxoplasmosis epidemiology. However, these bats can be important in the maintenance of Leptospira spp. in the environment.

  15. Efecto de la vacunación anti-leptospira en bovinos lecheros sobre la producción de anticuerpos anti-leptospira en trabajadores de lecherías de cuatro zonas de Costa Rica

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    Rafael González

    2007-07-01

    Full Text Available Objetivo: Este estudio experimental midió el efecto indirecto de la vacuna anti-Leptospira Leptoferm-5® (Pfizer® en la producción de anticuerpos anti-Leptospira en trabajadores de lecherías de cuatro zonas lecheras de Costa Rica. Materiales y Métodos: Tomaron parte en el estudio 171 vaqueros, 94 en el grupo tratamiento y 77 en el grupo control. A cada vaquero se le tomó una muestra sanguínea en tres diferentes momentos durante un año: la primera, antes de aplicar la vacuna en los animales, la segunda a los 6 meses y la tercera un año después de la primera vacunación. Se utilizó la técnica de micro aglutinación para la detección de anticuerpos anti-Leptospira interrogans serovares pomona, hardjo, canícola y grippotyphosa en el laboratorio del INCIENSA. Se utilizó la razón de prevalencias y el riesgo relativo para determinar si existió asociación entre la vacunación anti-Leptospira a las vacas y la seropositividad en los vaqueros. Resultados: En los tres muestreos se obtuvo un 10.27% (50/487 de muestras positivas a cualquiera de los serovares de Leptospira interrogans a los que fueron analizados. Tanto en el grupo tratamiento como en el control se observaron cambios en la seropositividad entre los distintos muestreos, con un aumento entre el primer y segundo muestreo (p Objective: This experimental study assessed the indirect effect of the anti-Leptospira vaccine Leptoferm-5® (Pfizer® regarding the production of anti-Leptospira antibodies in dairymen from four dairy areas in Costa Rica. Materials and Methods: 171 dairymen took part in the study; 94 in the treatment group and 77 in the control group. Three blood samples were taken from each worker three times throughout a year period: before the vaccination of the animals, and six and twelve months after the initial vaccination. The microscopic agglutination test (MAT was used to detect anti-Leptospira interrogans antibodies, specifically towards pomona, hardjo, canicola

  16. Preliminary Investigations on the Distribution of Leptospira Serovars in Domestic Animals in North-west Morocco.

    Science.gov (United States)

    Benkirane, A; Noury, S; Hartskeerl, R A; Goris, M G A; Ahmed, A; Nally, J E

    2016-04-01

    Leptospirosis is a neglected zoonosis of global importance with a complex epidemiology that affects humans, domestic and wild mammals. However, due to the diversity of clinical signs and difficulties of establishing a confirmatory laboratory diagnosis, the disease remains poorly investigated, particularly in the developing world. In Morocco, a descriptive study of the seroprevalence of Leptospira infection in animals has never been undertaken. To fill this gap, the current study was conducted on a subset of animals in north-west Morocco as a preliminary step towards understanding the epidemiological patterns of animal leptospirosis in the country. The study was conducted on 289 serum samples collected between January and April 2012 from dogs, cattle, sheep, goats and donkeys in the areas of Rabat-Temara, Sidi Kacem and Oulmes. All serum samples were tested by the MAT with 14 reference strains of the most prevalent pathogenic serovars of Leptospira and two serovars of non-pathogenic Leptospira. The overall seroprevalence of Leptospira in cattle, sheep, goats, dogs and donkeys was 15%, 18%, 20%, 21% and 20%, respectively. The most prevalent serogroups found in each species were Ballum, Sejroe, and Australis in cattle, Ballum, Australis and Sejroe in sheep, Australis and Ballum in goats, Javanica and Australis in donkey and Australis, Ballum and Canicola in dogs. Of all the serogroups tested in this study, Icterohaemorrhagiae, the only serogroup which has been previously reported in humans in Morocco, was rarely reactive. The majority of reactive sera were collected from low land areas. A large number of sera samples classified as seronegative when tested against pathogenic leptospires were positive when tested against non-pathogenic leptospires; this is suggestive of possible novel, as yet unclassified, Leptospira serovars in Morocco. Eleven of thirteen sheep urine samples were positive by real-time PCR confirming their role as Leptospira carriers in Morocco.

  17. Seroprevalence of Leptospira antibodies among populations at risk

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    Abdul-Baki Abdullah Al-Robasi

    2015-03-01

    Full Text Available Objective: This study was performed to assess the Leptospira IgG antibodies seroprevalence among populations at risk in Hodeida Governorate, Yemen. Methods: A total of 200 subjects (136 males and 64 females participated in this study during June and December 2012.They represented 10 sewage workers, 22 butchers, 16 construction workers, 108 agriculture workers, 20 hospital sanitary workers and 24 blood donors. Predesigned questionnaires and consent were taken from each individual. Blood samples were collected from subjects, and the sera were tested by ELISA to detect the presence of leptospira IgG antibodies. The possible related factors for seropositivity were evaluated. Results: Leptospira IgG antibodies were found positive in 42% of the participants. The highest seroprevalence level was detected in sewage workers (80%, followed by hospital sanitary workers (60%, construction workers (37.5% and farmers (37%. The lowest of antibodies was in butchers (36.4%. Seroprevalence among blood donors was 25% which was comparatively less than of the populations at risk. Seropositivity of Leptospira IgG antibodies was found higher among males than females (42.6% vs. 34.4%. The highest Leptospira antibodies seropositivity was among elderly participants (81.8%. The seropositivity of antibodies in population live in rural and urban areas was not significant differences. As for closely contacting with animals, the highest antibodies were discovered in people who had goats (80% and sheep (60.9%. Conclusion: Individuals engaged in risk activities are often exposed to leptospiral infection. Therefore, control and prevention policy toward these people are necessary. J Microbiol Infect Dis 2015;5(1: 1-4

  18. Serological survey of leptospiral infections in sheep, goats and dogs in Cordillera province, Bolivta.

    Science.gov (United States)

    Ciceroni, L; Bartoloni, A; Pinto, A; Guglielmetti, P; Valdez Vasquez, C; Gamboa Barahona, H; Roselli, M; Giannico, F; Paradisi, F

    1997-01-01

    A serological survey for antibodies to Leptospira spp. was conducted on sheep, goat and dog serum samples collected in three localities in Cordillera province in the southern part of the Santa Cruz Department (Bolivia) in 1992. A total of 98 sheep, 218 goats and 43 dogs were tested against 29 leptospiral serovars using the microscopic agglutination test. At the time of blood collection all of the examined animals appeared healthy and presented no clinical sign suggestive of leptospirosis. Antibody prevalences, as determined by positive results at a 1:100 dilution or higher, was 14.3% in sheep, 19.7% in goats, and 14.0% in dogs. Agglutinins against six serovars (poi. shermani, pomona, canicola, javanica, djasiman) were found in positive animals. The highest serological prevalence in sheep and goats was recorded for serovar poi, followed by pomona in sheep and shermani in goats. Titres to shermani were the commonest in dogs. The results of this survey indicate that leptospiral infection is common in south-east Bolivia and that serovars of several serogroups concur in the etiology.

  19. Detection of wild animals as carriers of Leptospira by PCR in the Pantanal biome, Brazil.

    Science.gov (United States)

    Vieira, Anahi S; Narduche, Lorena; Martins, Gabriel; Schabib Péres, Igor A H F; Zimmermann, Namor P; Juliano, Raquel S; Pellegrin, Aiesca O; Lilenbaum, Walter

    2016-11-01

    Leptospiral infection is widespread in wildlife. In this context, wild ecosystems in tropical countries hold a vast biodiversity, including several species that may act as potential reservoirs of leptospires. The Pantanal biome presents highly favorable environmental conditions for the occurrence of leptospirosis, such as high temperatures, constant flooding, and high biodiversity. The purpose of this study was to detect wild animals as carriers of Leptospira sp. using direct methods (PCR and culture) in the Pantanal biome, Brazil. A total of 35 animals were studied, namely Cerdocyon thous, Nasua nasua, Ozotoceros bezoarticus, and Sus scrofa species. Blood for serology (MAT) and urine for bacteriological culturing and PCR was sampled. The most prevalent serogroups were Javanica and Djasiman. Additionally, 40.6% of these animals presented PCR positive reactions. Seroreactivity associated with the high frequency of leptospiral carriers among the different studied species suggests a high level of exposure of the studied animals to pathogenic Leptospira strains. Our results are still limited and the actual role of the studied animals in the epidemiology of leptospirosis in the Pantanal region remains to be elucidated.

  20. Evaluation of cell binding activities of Leptospira ECM adhesins.

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    Gregory T Robbins

    2015-04-01

    Full Text Available Pathogenic spirochetes of the genus Leptospira are the causative agents of leptospirosis, a zoonotic infection that occurs globally. The bacteria colonize the renal proximal tubules of many animals and are shed in the urine. Contact with the urine, or with water contaminated with the urine of infected animals can cause infection of new host animals, including humans. Mechanisms of colonization of the proximal tubule and other tissues are not known, but specific interactions between bacterial adhesins and host substrates are likely to be critical in this process. Several extracellular matrix (ECM adhesins have been previously identified, but more recently, it has been shown that Leptospira bind more efficiently to cells than ECM. In this work, recombinant forms of five putative Leptospira ECM adhesins, namely LipL32, Loa22, OmpL1, p31/LipL45, and LenA were evaluated for binding to cells as well as an expanded variety of ECM components. Reproducible and significant adhesin activity was demonstrated only for OmpL1, which bound to both mammalian cell lines tested and to glycosaminoglycans (GAGs. While determination of biologically significant bacterial adhesion activity will require generation of site-directed mutant strains, our results suggest that OmpL1 is a strong candidate for future evaluation regarding the roles of the adhesin activity of the protein during L. interrogans infection.

  1. Characterization of Leptospira santarosai Serogroup Grippotyphosa Serovar Bananal Isolated from Capybara ( Hydrochaeris hydrochaeris ) in Brazil.

    Science.gov (United States)

    Moreno, Luisa Z; Miraglia, Fabiana; Marvulo, Maria F V; Silva, Jean C R; Paula, Catia D; Costa, Barbara L P; Morais, Zenaide M; Ferreira, Fernando; Neto, José S Ferreira; Dellagostin, Odir A; Hartskeerl, Rudy A; Vasconcellos, Silvio A; Moreno, Andrea M

    2016-07-01

    Leptospirosis is a widespread zoonosis caused by bacteria of the genus Leptospira. Rodents appear to be the most important reservoirs of infection. They contaminate the environment and food and can transmit the pathogen when they are consumed by carnivores. Capybara ( Hydrochaeris hydrochaeris ) are efficient reservoirs of Leptospira, and because they are in close contact with farm animals and are found in semiurban areas, they represent a risk to public health. We isolated five Leptospira strains from capybara kidneys in Sao Paulo State, Brazil, in 2001 and typed them using serologic and molecular techniques. These strains include the Leptospira santarosai serogroup Grippotyphosa serovar Bananal. Pulsed field gel electrophoresis resulted in a unique pattern distinct from the reference strains, and the isolates clustered with greater than 85% similarity. The isolates also presented higher growth rates than other Leptospira serovars, with high minimal inhibitory concentration values for most of the tested antibiotics, with the exception of penicillin and ampicillin. This isolation and characterization of the L. santarosai serogroup Grippotyphosa serovar Bananal from capybara, highlights the importance of wild and sinantropic rodents as carriers of pathogenic leptospires.

  2. Prevalence and Genotype Allocation of Pathogenic Leptospira Species in Small Mammals from Various Habitat Types in Germany.

    Science.gov (United States)

    Obiegala, Anna; Woll, Dietlinde; Karnath, Carolin; Silaghi, Cornelia; Schex, Susanne; Eßbauer, Sandra; Pfeffer, Martin

    2016-03-01

    Small mammals serve as most important reservoirs for Leptospira spp., the causative agents of Leptospirosis, which is one of the most neglected and widespread zoonotic diseases worldwide. The knowledge about Leptospira spp. occurring in small mammals from Germany is scarce. Thus, this study's objectives were to investigate the occurrence of Leptospira spp. and the inherent sequence types in small mammals from three different study sites: a forest in southern Germany (site B1); a National Park in south-eastern Germany (site B2) and a renaturalised area, in eastern Germany (site S) where small mammals were captured. DNA was extracted from kidneys of small mammals and tested for Leptospira spp. by real-time PCR. Positive samples were further analysed by duplex and conventional PCRs. For 14 positive samples, multi locus sequence typing (MLST) was performed. Altogether, 1213 small mammals were captured: 216 at site B1, 456 at site B2 and 541 at site S belonging to following species: Sorex (S.) araneus, S. coronatus, Apodemus (A.) flavicollis, Myodes glareolus, Microtus (Mi.) arvalis, Crocidura russula, Arvicola terrestris, A. agrarius, Mustela nivalis, Talpa europaea, and Mi. agrestis. DNA of Leptospira spp. was detected in 6% of all small mammals. At site B1, 25 small mammals (11.6%), at site B2, 15 small mammals (3.3%) and at site S, 33 small mammals (6.1%) were positive for Leptospira spp. Overall, 54 of the positive samples were further determined as L. kirschneri, nine as L. interrogans and four as L. borgpetersenii while five real-time PCR-positive samples could not be further determined by conventional PCR. MLST results revealed focal occurrence of L. interrogans and L. kirschneri sequence type (ST) 117 while L. kirschneri ST 110 was present in small mammals at all three sites. Further, this study provides evidence for a particular host association of L. borgpetersenii to mice of the genus Apodemus.

  3. Maximizing the chances of detecting pathogenic leptospires in mammals

    DEFF Research Database (Denmark)

    Tulsiani, Suhella; Graham, G C; Dohnt, M F

    2011-01-01

    of these studies have now been carefully analysed in attempts to see which method of detection and type of test sample were best. The effects of pentobarbitone sodium used to euthanize wild mammals before collection of necropsy samples, on the survival and detection of leptospires in vitro, were also explored....... In the earlier field investigation, serum, renal tissue and urine were collected from wild mammals, for the detection of pathogenic leptospires by culture, the microscopic agglutination test (MAT), real-time PCR and silver impregnation of smears. Although 27.6% of the rodents investigated were found leptospire....../ml, did not affect the viability or the detection of leptospires in culture, and is therefore unlikely to reduce the chances of isolating leptospires from an animal that has been euthanized with the compound. It appears that collecting multiple samples from each mammal being checked will improve...

  4. Genetic diversity of Leptospira in northwestern Colombia: first report of Leptospira santarosai as a recognised leptospirosis agent

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    Ronald Guillermo Peláez Sanchez

    Full Text Available The region of Antioquia in northeastern Colombia has the highest number of reported leptospirosis cases in the country. It also shows high seroprevalence indexes in the general population and socio-environmental conditions favourable for the transmission of the disease between humans and animals. In this study, 25 Leptospira isolates from Colombia’s Antioquia department were identified to the species level as L. santarosai (12, L. interrogans (9 and L. meyeri (4 using phylogenetic analysis of the Amidohydrolase gene. Typing at the serovar level was performed using multilocus sequence typing (MLST and monoclonal antibodies. The serovars Canalzonae, Babudieri, Alice, Beye, and Copenhageni have been identified as causing human or animal infections in Antioquia, Colombia. The four environmental isolates were not identified to the serovar level. L. santarosai serovar Canalzonae and Alice were identified as new etiologic agents of human leptospirosis in Antioquia, Colombia. This paper reports species and serovars that were previously unknown in the region.

  5. Genetic diversity of Leptospira in northwestern Colombia: first report of Leptospira santarosai as a recognised leptospirosis agent

    Science.gov (United States)

    Peláez Sanchez, Ronald Guillermo; Lopez, Juan Álvaro; Pereira, Martha María; Arboleda Naranjo, Margarita; Agudelo-Flórez, Piedad

    2016-01-01

    The region of Antioquia in northeastern Colombia has the highest number of reported leptospirosis cases in the country. It also shows high seroprevalence indexes in the general population and socio-environmental conditions favourable for the transmission of the disease between humans and animals. In this study, 25 Leptospira isolates from Colombia’s Antioquia department were identified to the species level as L. santarosai (12), L. interrogans (9) and L. meyeri (4) using phylogenetic analysis of the Amidohydrolase gene. Typing at the serovar level was performed using multilocus sequence typing (MLST) and monoclonal antibodies. The serovars Canalzonae, Babudieri, Alice, Beye, and Copenhageni have been identified as causing human or animal infections in Antioquia, Colombia. The four environmental isolates were not identified to the serovar level. L. santarosai serovar Canalzonae and Alice were identified as new etiologic agents of human leptospirosis in Antioquia, Colombia. This paper reports species and serovars that were previously unknown in the region. PMID:27982303

  6. Serologic and Molecular Studies of Leptospira and Leptospirosis among Rats in the Philippines

    Science.gov (United States)

    Villanueva, Sharon Y. A. M.; Ezoe, Hirokazu; Baterna, Rubelia A.; Yanagihara, Yasutake; Muto, Maki; Koizumi, Nobuo; Fukui, Takashi; Okamoto, Yoshihiro; Masuzawa, Toshiyuki; Cavinta, Lolita L.; Gloriani, Nina G.; Yoshida, Shin-ichi

    2010-01-01

    Rats are known to be the most important reservoirs and transmission sources of leptospirosis. However, the status of leptospirosis in the Philippines regarding reservoirs and transmission remains unknown. A survey was conducted in Metro Manila and Laguna that analyzed samples obtained from 106 rats. Using the microscopic agglutination test, we found that 92% of rat serum samples were positive for anti-Leptospira antibodies; the most common infecting serovars were Manilae, Hebdomadis, and Losbanos. On the basis of pulsed-field gel electrophoresis and gyrase B gene sequence analyses, four groups of rat kidney isolates were found: L. interrogans serovar Manilae, serovar Losbanos, and serogroup Grippotyphosa, and L. borgpetersenii serogroup Javanica. Most isolates were lethal after experimental infection of golden Syrian hamsters. Results showed that these four Leptospira serovars and serogroups are circulating among rats, and that these animals may be one of the possible transmission sources of leptospirosis in the Philippines. PMID:20439972

  7. Genomic Analysis of a New Serovar of Leptospira weilii Serogroup Manhao

    Science.gov (United States)

    Zheng, Huajun; Zhang, Ying; Wang, Yuezhu; Zhang, Jinlong; Li, Zhe; Cui, Shenghui; Xin, Xiaofang; Ye, Qiang; Chang, Yung-Fu; Wang, Junzhi

    2017-01-01

    Leptospirosis, caused by pathogenic Leptospira spp., is recognized as an important emerging zoonotic disease throughout the world. In this study, multiple approaches were used to characterize the recently discovered serovar Heyan strain L231. This strain can infect guinea pigs and belonged to the pathogenic species L. weilii. Genome sequencing analysis revealed the draft genome of 4.2 M bp with a G+C content of 40.67% for strain L231, and a total of 4,794 ORFs were identified. The strain L231 genome was found to have a larger LPS biosynthesis locus than that of strains L. interrogans serovar Lai and L. borgpetersenii serovar Hardjobovis. Phylogenomic reconstructions showed that the evolutionary position of L. weilii serovar Heyan was different from that of other serovars from serogroup Manhao. These findings may lead us to a better understanding of Leptospira pathogenesis and evolution. PMID:28210253

  8. Polymorphism Identification of VNTR30 and VNTR36 Loci in Pathogenic Leptospira Serovares in Iran

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    Sama Reza Soltani

    2014-01-01

    Full Text Available Abstract Background and objective: Leptospirosis, is the zoonotic disease which is characterized as an emerging infectious disease with large documented outbreaks. Epidemiological investigations are needed to distinguish outbreak situations or to trace reservoirs of the organisms. Today MLVA technique is used for segregating and identifying of Leptospira serovares. The method has potential application in furthering the understanding of Leptospiral molecular epidemiology. The propose of this study is rapid identification of pathogenic Leptospira serovares in Iran. Materials and methods: A total 12 pathogenic Leptospiral serovares and 1 saprophytic serovar that maintained from microbial bank of Razi Vaccine and Serum Research Institute, Karaj, Iran. The Genomic DNA of Leptospira was extracted .PCR was performed with primers for loci VNTR30, VNTR36. The amplified fragments were analyzed by gel electrophoresis . The sizes of the amplified products were estimated by comparison with a 100 -bp ladder. Results: All loci successfully amplified in all pathogenic leptospira serovars. The saprophytic serovar showed no amplified fragments. The results show VNTR30 has a wide range of polymorphism between Atumnalis, Hardjo St.Hardjo bovis, Pomona St. UT364, Icterohaemorrhagia St. RGA and VNTR36 shows variation between Canicola St. Hondutrecht IV , Hardjo St.Hardjo bovis, Pomona St. UT364 Conclusion: Most of the VNTR patterns were similar in different serovares while showed significant differences with same serovares of South America and Europe. On the other our serovares resemble Southeast Asia serovares because of the same geographical area. Among serovares Canicola St. Hondutrecht IV and Canicola St. Fiocruz LV133 identified by MLVA, PFGE was unable to differentiate them. In conclusion MLVA technique with wide range of polymorphism is known as good marker for identification serovares.

  9. LipL21 mRNA expression in lungs of hamsters infected with pathogenic Leptospira

    Institute of Scientific and Technical Information of China (English)

    Chintana Chirathaworn; Namo Suksomyos; Somchai Utivamek; Somboon Keelawat; Duangjai Suwancharoen; Duangporn Phulsuksombati; Yong Poovorawan

    2009-01-01

    Objective:Pulmonary haemorrhage is an increasing cause of death in leptospirosis patients.However,molecu-lar mechanism underlying pathologies in this organ is not clearly understood.It has been shown that sodium transport was disturbed following Leptospira infection.LipL21 is the second abundant outer membrane protein found only in pathogenic Leptospira.Its expression in vivo has been shown which suggests that this protein may be involved in survival in hosts or pathogenesis.However,the expression of this protein in host organs and its role in lung pathology has not been demonstrated.In this study we demonstrated the expression of LipL21 in lungs of hamsters infected with pathogenic Leptospira.Methods:Lung tissues were collected from Golden Syri-an hamsters injected with Leptospira interrogans serovar Pyrogenes at days 3,5 and 7 post-infection.Four ham-sters were used for each time point.Lungs from non-infected hamsters were collected as a control group.Li-pL21 mRNA expression in lung tissues was investigated by reverse transcription and nested PCR.Results:Li-pL21 mRNA expression was detected in all lung tissues from hamsters infected with pathogenic Leptospira.No PCR product was detected when tissues from non-infected hamsters were investigated.Conclusion:Our data demonstrated that LipL21 is expressed in lungs of hamsters infected with pathogenic Leptospira.Additional ex-periments such as quantitation and localization of LipL21 expression in lungs will provide further information whether this protein is involved in pathogenesis.

  10. Leptospira spp detection by Polymerase Chain Reaction (PCR in clinical samples of captive black-capped Capuchin monkey (Cebus apella

    Directory of Open Access Journals (Sweden)

    Scarcelli Eliana

    2003-01-01

    Full Text Available Leptospirosis is a widely distributed zoonosis that affects domestic and wild animals, and that has the man as the end point of its epidemiological chain. Leptospirosis diagnosis in primates is more difficult than in other animal species, as clinical signs and lesions are less evident and antibody response is detected only for short periods. The aim of this article was to describe the detection of Leptospira spp using polymerase chain reaction (PCR, in clinical samples from one captive black-capped Capuchin monkey (Cebus apella, which presented characteristics compatible with leptospirosis (jaundice and haemorrhagic kdney in the macroscopic post-mortem examination. A friable kidney fragment and urine sample were cultured and submitted to experimental inoculation in guinea pigs and PCR using genus specific primer pair targeting the 16S rRNA region from Leptospira interrogans serovar canicola. Isolation of the agent was negative both in culture and experimental inoculation. The PCR amplification of the clinical samples showed a 330 pb amplified fragment that corresponds to the Leptospira genus. Based on these results PCR was considered an important tool for leptospira detection in nonhumam primates, more sensitive and specific than other techniques, especially considering that the viability of the pathogen was not possible. These advantages enable the detection of the leptospiras in urine and kidney, even when autolysed, frozen or badly conserved, which prevented the isolation and experimental inoculation from positive results.

  11. Prevalence of Leptospira antibodies in wild boars (Sus scrofa) from Northern Portugal: risk factor analysis.

    Science.gov (United States)

    Vale-Gonçalves, H M; Cabral, J A; Faria, M C; Nunes-Pereira, M; Faria, A S; Veloso, O; Vieira, M L; Paiva-Cardoso, Md N

    2015-07-01

    Leptospirosis is a zoonosis of worldwide distribution, caused by infection with pathogenic spirochaetes of the genus Leptospira. The wild boar (Sus scrofa), an important hunting species in Europe, seems to play a significant role in the epidemiological cycle of leptospirosis. A total of 101 serum samples from wild boar hunted in Northern Portugal were analysed for leptospiral antibodies detection by microscopic agglutination test. Sera were collected during hunting seasons (2011-2013) and tested with 17 different pathogenic serovars of Leptospira. Antibodies against nine serovars were detected in 66 (65·4%) of these sera. Serovars Tarassovi and Altodouro exhibited the highest seroreactivity rates (23·8% and 16·8%, respectively), followed by Autumnalis (7·9%) and Bratislava (6·9%). Age and district of origin were found to be risk factors for the presence of leptospiral antibodies in contrast to gender. From a One Health perspective, this study revealed that wild boar should be considered as a potential source of leptospirosis dissemination for humans and animal species (domestic and wild) in shared environments, particularly in the Trás-os-Montes region.

  12. Diagnóstico molecular de Leptospira spp em matrizes suínas descartadas

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    Sérgio José de Oliveira

    2007-02-01

    Full Text Available O Diagnóstico de leptospirose foi efetuado através de método molecular, histopatológico e sorológico em 30 matrizes suínas, descartadas, no Rio Grande do Sul, Brasil. Os objetivos foram comparar a eficiência dos 3 métodos, verificar a sensibilidade de um método de PCR que utiliza um primer único baseado na seqüência de um elemento repetitivo do genoma de Leptospira interrogans, bem como verificar a possível detecção de leptospiras em vários tecidos, incluindo o trato genital. Os animais foram selecionados com base no teste de aglutinação microscópica para incluir tanto animais negativos como positivos e com baixos e altos títulos sorológicos. As maiores freqüências (90 % dos aniamis positivos e títulos (100 to 800 foram observados para L. interrogans serovar bratislava. Leptospiras foram detectadas por histopatologia em apenas 9 matrizes, todas com altos títulos (pelo menos 100. Um produto de PCR de 438 bp foi observado em todos os animais (fragmentos de 25 rins, 24 úteros e 9 ovidutos. Produtos de PCR similares foram obtidos em DNA de culturas de leptospiras patogênicas, enquanto a não patogênica, L. patoc apresentou um padrão distinto. Nenhum produto de amplificação de DNA de Leptospira spp foi detectado em DNA de culturas de Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella sp, Streptococcus sp and Staphylococcus aureus, ou de sangue de dois leitões. O método molecular foi, assim, específico e o mais eficiente para detectar baixos níveis de patógeno, sendo capaz de diferenciar leptospiras patogênicas e não patogênicas.

  13. Cross-species surveillance of Leptospira in domestic and peri-domestic animals in Mahalla City, Gharbeya Governorate, Egypt.

    Science.gov (United States)

    Felt, Stephen A; Wasfy, Momtaz O; El-Tras, Wael F; Samir, Ahmed; Rahaman, Bassem Abdel; Boshra, Marie; Parker, Tina M; Hatem, Mahmoud Essam; El-Bassiouny, Ahmed Ahmed; Murray, Clinton K; Pimentel, Guillermo

    2011-03-01

    A survey of 179 animals (black rats, dogs, sheep, buffaloes, cattle, donkeys, weasels, and cats) for Leptospira infection was conducted in Mahalla City (Lower Egypt). Blood, urine, and kidney were collected and tested by culture, microscopic agglutination test (MAT), and/or polymerase chain reaction (PCR). Among rats, 26% were positive by PCR, including 7% that were also positive by culture for L. interrogans serovars Grippotyphosa, Pyrogenes, and Icterohaemorrhagiae. L. borpetersenii serovar Polonica was isolated for the first time in Egypt in three rats. MAT titers ≥ 1:800 were observed in 11% of rats and 12% of dogs. L. interrogans serovar Grippotyphosa was detected in one cat. Sheep and donkeys were negative for leptospirosis by all methods. Buffaloes and cattle were seropositive in 20% and 44% of animals, respectively. Data indicate that several pathogenic serovars are circulating in the animals, which may pose exposure risks and account for high rates of acute febrile illness.

  14. Identification of Tenrec ecaudatus, a Wild Mammal Introduced to Mayotte Island, as a Reservoir of the Newly Identified Human Pathogenic Leptospira mayottensis

    Science.gov (United States)

    Lagadec, Erwan; Gomard, Yann; Le Minter, Gildas; Cordonin, Colette; Cardinale, Eric; Ramasindrazana, Beza; Dietrich, Muriel; Goodman, Steven M; Tortosa, Pablo; Dellagi, Koussay

    2016-01-01

    Leptospirosis is a bacterial zoonosis of major concern on tropical islands. Human populations on western Indian Ocean islands are strongly affected by the disease although each archipelago shows contrasting epidemiology. For instance, Mayotte, part of the Comoros Archipelago, differs from the other neighbouring islands by a high diversity of Leptospira species infecting humans that includes Leptospira mayottensis, a species thought to be unique to this island. Using bacterial culture, molecular detection and typing, the present study explored the wild and domestic local mammalian fauna for renal carriage of leptospires and addressed the genetic relationships of the infecting strains with local isolates obtained from acute human cases and with Leptospira strains hosted by mammal species endemic to nearby Madagascar. Tenrec (Tenrec ecaudatus, Family Tenrecidae), a terrestrial mammal introduced from Madagascar, is identified as a reservoir of L. mayottensis. All isolated L. mayottensis sequence types form a monophyletic clade that includes Leptospira strains infecting humans and tenrecs on Mayotte, as well as two other Malagasy endemic tenrecid species of the genus Microgale. The lower diversity of L. mayottensis in tenrecs from Mayotte, compared to that occurring in Madagascar, suggests that L. mayottensis has indeed a Malagasy origin. This study also showed that introduced rats (Rattus rattus) and dogs are probably the main reservoirs of Leptospira borgpetersenii and Leptospira kirschneri, both bacteria being prevalent in local clinical cases. Data emphasize the epidemiological link between the two neighbouring islands and the role of introduced small mammals in shaping the local epidemiology of leptospirosis. PMID:27574792

  15. Identification of Tenrec ecaudatus, a Wild Mammal Introduced to Mayotte Island, as a Reservoir of the Newly Identified Human Pathogenic Leptospira mayottensis.

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    Erwan Lagadec

    2016-08-01

    Full Text Available Leptospirosis is a bacterial zoonosis of major concern on tropical islands. Human populations on western Indian Ocean islands are strongly affected by the disease although each archipelago shows contrasting epidemiology. For instance, Mayotte, part of the Comoros Archipelago, differs from the other neighbouring islands by a high diversity of Leptospira species infecting humans that includes Leptospira mayottensis, a species thought to be unique to this island. Using bacterial culture, molecular detection and typing, the present study explored the wild and domestic local mammalian fauna for renal carriage of leptospires and addressed the genetic relationships of the infecting strains with local isolates obtained from acute human cases and with Leptospira strains hosted by mammal species endemic to nearby Madagascar. Tenrec (Tenrec ecaudatus, Family Tenrecidae, a terrestrial mammal introduced from Madagascar, is identified as a reservoir of L. mayottensis. All isolated L. mayottensis sequence types form a monophyletic clade that includes Leptospira strains infecting humans and tenrecs on Mayotte, as well as two other Malagasy endemic tenrecid species of the genus Microgale. The lower diversity of L. mayottensis in tenrecs from Mayotte, compared to that occurring in Madagascar, suggests that L. mayottensis has indeed a Malagasy origin. This study also showed that introduced rats (Rattus rattus and dogs are probably the main reservoirs of Leptospira borgpetersenii and Leptospira kirschneri, both bacteria being prevalent in local clinical cases. Data emphasize the epidemiological link between the two neighbouring islands and the role of introduced small mammals in shaping the local epidemiology of leptospirosis.

  16. Induction of Boosted Immune Response in Mice by Leptospiral Surface Proteins Expressed in Fusion with DnaK

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    Marina V. Atzingen

    2014-01-01

    Full Text Available Leptospirosis is an important global disease of human and veterinary concern. Caused by pathogenic Leptospira, the illness was recently classified as an emerging infectious disease. Currently available veterinarian vaccines do not induce long-term protection against infection and do not provide cross-protective immunity. Several studies have suggested the use of DnaK as an antigen in vaccine formulation, due to an exceptional degree of immunogenicity. We focused on four surface proteins: rLIC10368 (Lsa21, rLIC10494, rLIC12690 (Lp95, and rLIC12730, previously shown to be involved in host-pathogen interactions. Our goal was to evaluate the immunogenicity of the proteins genetically fused with DnaK in animal model. The chosen genes were amplified by PCR methodology and cloned into pAE, an E. coli vector. The recombinant proteins were expressed alone or in fusion with DnaK at the N-terminus. Our results demonstrate that leptospiral proteins fused with DnaK have elicited an enhanced immune response in mice when compared to the effect promoted by the individual proteins. The boosted immune effect was demonstrated by the production of total IgG, lymphocyte proliferation, and significant amounts of IL-10 in supernatant of splenocyte cell cultures. We believe that this approach could be employed in vaccines to enhance presentation of antigens of Leptospira to professional immune cells.

  17. A single multilocus sequence typing (MLST scheme for seven pathogenic Leptospira species.

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    Siriphan Boonsilp

    Full Text Available The available Leptospira multilocus sequence typing (MLST scheme supported by a MLST website is limited to L. interrogans and L. kirschneri. Our aim was to broaden the utility of this scheme to incorporate a total of seven pathogenic species.We modified the existing scheme by replacing one of the seven MLST loci (fadD was changed to caiB, as the former gene did not appear to be present in some pathogenic species. Comparison of the original and modified schemes using data for L. interrogans and L. kirschneri demonstrated that the discriminatory power of the two schemes was not significantly different. The modified scheme was used to further characterize 325 isolates (L. alexanderi [n = 5], L. borgpetersenii [n = 34], L. interrogans [n = 222], L. kirschneri [n = 29], L. noguchii [n = 9], L. santarosai [n = 10], and L. weilii [n = 16]. Phylogenetic analysis using concatenated sequences of the 7 loci demonstrated that each species corresponded to a discrete clade, and that no strains were misclassified at the species level. Comparison between genotype and serovar was possible for 254 isolates. Of the 31 sequence types (STs represented by at least two isolates, 18 STs included isolates assigned to two or three different serovars. Conversely, 14 serovars were identified that contained between 2 to 10 different STs. New observations were made on the global phylogeography of Leptospira spp., and the utility of MLST in making associations between human disease and specific maintenance hosts was demonstrated.The new MLST scheme, supported by an updated MLST website, allows the characterization and species assignment of isolates of the seven major pathogenic species associated with leptospirosis.

  18. Emerging Infectious Disease Implications of Invasive Mammalian Species: The Greater White-Toothed Shrew (Crocidura russula) Is Associated With a Novel Serovar of Pathogenic Leptospira in Ireland

    Science.gov (United States)

    Nally, Jarlath E.; Arent, Zbigniew; Bayles, Darrell O.; Hornsby, Richard L.; Gilmore, Colm; Regan, Siobhan; McDevitt, Allan D.; Yearsley, Jon; Fanning, Séamus; McMahon, Barry J.

    2016-01-01

    The greater white-toothed shrew (Crocidura russula) is an invasive mammalian species that was first recorded in Ireland in 2007. It currently occupies an area of approximately 7,600 km2 on the island. C. russula is normally distributed in Northern Africa and Western Europe, and was previously absent from the British Isles. Whilst invasive species can have dramatic and rapid impacts on faunal and floral communities, they may also be carriers of pathogens facilitating disease transmission in potentially naive populations. Pathogenic leptospires are endemic in Ireland and a significant cause of human and animal disease. From 18 trapped C. russula, 3 isolates of Leptospira were cultured. However, typing of these isolates by standard serological reference methods was negative, and suggested an, as yet, unidentified serovar. Sequence analysis of 16S ribosomal RNA and secY indicated that these novel isolates belong to Leptospira alstonii, a unique pathogenic species of which only 7 isolates have been described to date. Earlier isolations were limited geographically to China, Japan and Malaysia, and this leptospiral species had not previously been cultured from mammals. Restriction enzyme analysis (REA) further confirms the novelty of these strains since no similar patterns were observed with a reference database of leptospires. As with other pathogenic Leptospira species, these isolates contain lipL32 and do not grow in the presence of 8-azagunaine; however no evidence of disease was apparent after experimental infection of hamsters. These isolates are genetically related to L. alstonii but have a novel REA pattern; they represent a new serovar which we designate as serovar Room22. This study demonstrates that invasive mammalian species act as bridge vectors of novel zoonotic pathogens such as Leptospira. PMID:27935961

  19. Emerging Infectious Disease Implications of Invasive Mammalian Species: The Greater White-Toothed Shrew (Crocidura russula) Is Associated With a Novel Serovar of Pathogenic Leptospira in Ireland.

    Science.gov (United States)

    Nally, Jarlath E; Arent, Zbigniew; Bayles, Darrell O; Hornsby, Richard L; Gilmore, Colm; Regan, Siobhan; McDevitt, Allan D; Yearsley, Jon; Fanning, Séamus; McMahon, Barry J

    2016-12-01

    The greater white-toothed shrew (Crocidura russula) is an invasive mammalian species that was first recorded in Ireland in 2007. It currently occupies an area of approximately 7,600 km2 on the island. C. russula is normally distributed in Northern Africa and Western Europe, and was previously absent from the British Isles. Whilst invasive species can have dramatic and rapid impacts on faunal and floral communities, they may also be carriers of pathogens facilitating disease transmission in potentially naive populations. Pathogenic leptospires are endemic in Ireland and a significant cause of human and animal disease. From 18 trapped C. russula, 3 isolates of Leptospira were cultured. However, typing of these isolates by standard serological reference methods was negative, and suggested an, as yet, unidentified serovar. Sequence analysis of 16S ribosomal RNA and secY indicated that these novel isolates belong to Leptospira alstonii, a unique pathogenic species of which only 7 isolates have been described to date. Earlier isolations were limited geographically to China, Japan and Malaysia, and this leptospiral species had not previously been cultured from mammals. Restriction enzyme analysis (REA) further confirms the novelty of these strains since no similar patterns were observed with a reference database of leptospires. As with other pathogenic Leptospira species, these isolates contain lipL32 and do not grow in the presence of 8-azagunaine; however no evidence of disease was apparent after experimental infection of hamsters. These isolates are genetically related to L. alstonii but have a novel REA pattern; they represent a new serovar which we designate as serovar Room22. This study demonstrates that invasive mammalian species act as bridge vectors of novel zoonotic pathogens such as Leptospira.

  20. The progress in the research of leptospires%钩端螺旋体研究进展

    Institute of Scientific and Technical Information of China (English)

    黄莉莉; 郭晓奎

    2010-01-01

    钩端螺旋体病是一种由致病性钩端螺旋体感染引起的人畜共患病.研究发现,致病性钩端螺旋体具有独特的基因组结构,可分为不同的血清型或基因组种.钩端螺旋体的传播受菌株、宿主免疫力以及环境等多种因素的影响.钩端螺旋体具有强大的侵袭力及多种毒力因子,并可诱导宿主产生免疫病理损伤,从而引起不同的临床表现.由于缺少用于钩端螺旋体操作的基因工具,因而人们对钩端螺旋体的致病机制仍所知甚少.准确的早期诊断方法有利于钩端螺旋体病的治疗,而安全、高效的疫苗则是预防钩端螺旋体病的最好方法.%Leptospirosis is a zoonosis caused by infection with pathogenic Leptospira species. The studies have suggested that pathogenic leptospires possess unique structure of genome and are classified into different serovars or genomospecies. Transmission of leptospirosis is affected by a number of aspects, including strain, host immunity, and environment. Pathogenic leptospires with many virulent factors have strong invasive-ness and can induce immunopathological damages in host, causing a diversity of clinical manifestations. The pathogenesis of leptospires is known very little, due mainly to the absence of genetic tools for the manipulation of leptospires. Earlier and accurate diagnosis can be helpful to treat leptospirosis. The safe and effective vaccine is the best method for prevention of leptospirosis.

  1. Cloning and sequencing of the gene encoding LipL21 in the vaccinal leptospira serovars

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    Rasoul Hoseinpur

    2016-01-01

    Full Text Available Background: Leptospirosis is a zoonotic disease in humans and animals, caused by the bacterium Leptospira interrogans. Gene expressing LipL21 is one of the genes identified in the bacterium, existing only in the pathogenic strains. The aim of this study was to cloning and analyzing the sequence of the gene encoding surface lipoprotein, LipL21, in five vaccinal leptospira serovars in Iran. Material and Methods: Pathogenic Leptospira interrogans serovars were cultured in EMJH medium with 10% rabbit serum. After genomic DNA extraction, PCR with specific primers was employed and the resulting product inserted in a vector then transferred into E. Coli DH5&alpha. The recombinant plasmids were finally sent for sequencing. Results: The analysis of gene lipL21 in domestic vaccinal serovars and comparison of them with other serovars in the GenBank database revealed that three vaccinal serovars serjo hardjo, canicola and pomona had 100% similarity with each other and grippotyphosa serovar had the highest difference with the vaccinal serovars. In general, the results showed that this gene is a highly conserved gene in the domestic vaccinal serovars and serovars in the GenBank database with more than 95.7 percent similarity. Conclusion: These results showed that the gene, lipL21, is highly conserved in the vaccinal serovars (similarities > 96.4 %. Therefore, the gene encoding surface protein LipL21 can serve as a useful serologic test with high specificity and sensitivity for diagnosis of leptospirosis in clinical samples and in future as an effective subunit vaccine candidate to be used.

  2. A small scale survey of Leptospira in mammals from eastern Poland.

    Science.gov (United States)

    Wójcik-Fatla, Angelina; Zając, Violetta; Sroka, Jacek; Piskorski, Michał; Cisak, Ewa; Sawczyn, Anna; Dutkiewicz, Jacek

    2013-01-01

    Samples of 30 dead small mammals each were collected on area 'A' located in eastern Poland and exposed to floods by the Vistula river, and on area 'B', also located in eastern Poland, but not exposed to floods. Kidneys and livers of the mammals were examined by the PCR and nested PCR methods for the presence of Leptospira DNA. From 7 species of small mammals examined, the presence of Leptospira DNA was detected in 2 of them. The prevalence of positive results was greatest in Apodemus agrarius which was the mostly numerous mammal species (14 out of total 39 specimens, 35.9%). The presence of Leptospira DNA was also found in Microtus arvalis (1 out of 1 specimen, 100%), whereas the remaining 5 species (Apodemus flavicollis , Apodemus sylvaticus, Microtus agrestis, Myodes glareolus, Sorex araneus) were negative. No significant difference in the prevalence of positive findings was found between the small mammals from areas 'A' exposed to flooding, compared to those from area 'B' not exposed to flooding (20.0% vs. 30.0%, p=0.3748). The overall positivity of the examined small mammals population from areas 'A' and 'B' was 25.0%. The prevalence of dual positivity (leptospiral DNA found both in kidney and liver) was greater in the mammals from areas exposed to flooding compared to those from areas not exposed to flooding (16.7% vs. 6.7%), but this dependence was also not significant (p=0.2382).

  3. Association between Opisthorchis viverrini and Leptospira spp. infection in endemic Northeast Thailand.

    Science.gov (United States)

    Van, Chinh Dang; Doungchawee, Galayanee; Suttiprapa, Sutas; Arimatsu, Yuji; Kaewkes, Sasithorn; Sripa, Banchob

    2016-10-13

    Opisthorchiasis caused by Opisthorchis viverrini is an important foodborne trematodiasis in Thailand, Laos and Cambodia. Interestingly, the opisthorchiasis endemic region overlaps with an area of leptospirosis emergence. Here we report an association between opisthorchiasis and leptospirosis in Thailand. Of 280 sera collected from villagers living around the Lawa wetland complex in Khon Kaen province, 199 (71%) were seropositive for leptospirosis by immunochromatography. Individuals with O. viverrini infection had a significantly higher rate of leptospirosis than those without (P=0.001). Significant higher leptospirosis prevalence was found in males than females (P=0.002). However, females but not males with O. viverrini infection showed a significantly higher seroprevalence of leptospirosis. Twenty-one of 35 environmental samples from the lake (water, mud and fish skin mucus) were positive for Leptospira spp. DNA sequencing, sequence alignment, and phylogenetic analysis of some positive nested PCR products revealed both pathogenic and intermediate pathogenic strains of Leptospira in the samples. Strikingly, O. viverrini metacercariae from the fish were positive for L. interrogans. These results suggest a close association between opisthorchiasis and leptospirosis. Contact with water, mud or eating raw fish harboring liver fluke metacercariae may be risk factors for Leptospira infection.

  4. High Leptospira Diversity in Animals and Humans Complicates the Search for Common Reservoirs of Human Disease in Rural Ecuador

    Science.gov (United States)

    Chiriboga, Jorge; Miller, Erin; Olivas, Sonora; Birdsell, Dawn; Hepp, Crystal; Hornstra, Heidie; Schupp, James M.; Morales, Melba; Gonzalez, Manuel; Reyes, Soraya; de la Cruz, Carmen; Keim, Paul; Hartskeerl, Rudy; Trueba, Gabriel; Pearson, Talima

    2016-01-01

    Background Leptospirosis is a zoonotic disease responsible for high morbidity around the world, especially in tropical and low income countries. Rats are thought to be the main vector of human leptospirosis in urban settings. However, differences between urban and low-income rural communities provide additional insights into the epidemiology of the disease. Methodology/Principal findings Our study was conducted in two low-income rural communities near the coast of Ecuador. We detected and characterized infectious leptospira DNA in a wide variety of samples using new real time quantitative PCR assays and amplicon sequencing. We detected infectious leptospira in a high percentage of febrile patients (14.7%). In contrast to previous studies on leptospirosis risk factors, higher positivity was not found in rats (3.0%) but rather in cows (35.8%) and pigs (21.1%). Six leptospira species were identified (L. borgpetersenii, L kirschnerii, L santarosai, L. interrogans, L noguchii, and an intermediate species within the L. licerasiae and L. wolffii clade) and no significant differences in the species of leptospira present in each animal species was detected (χ2 = 9.89, adj.p-value = 0.27). Conclusions/Significance A large portion of the world’s human population lives in low-income, rural communities, however, there is limited information about leptospirosis transmission dynamics in these settings. In these areas, exposure to peridomestic livestock is particularly common and high prevalence of infectious leptospira in cows and pigs suggest that they may be the most important reservoir for human transmission. Genotyping clinical samples show that multiple species of leptospira are involved in human disease. As these genotypes were also detected in samples from a variety of animals, genotype data must be used in conjunction with epidemiological data to provide evidence of transmission and the importance of different potential leptospirosis reservoirs. PMID:27622673

  5. Nuclease activity and cytotoxicity to host cells of toxic protein VapC produced by Leptospira species%钩端螺旋体毒性蛋白VapC核酸酶活性及其对宿主细胞毒性作用的研究

    Institute of Scientific and Technical Information of China (English)

    辛晓阳; 林旭瑷; 李立伟; 严杰

    2012-01-01

    Objective To determine the function of toxic protein VapC in toxin/antitoxin system of Leptospira species and the cytotoxicity to host cells of the toxic protein.Methods Using genomic DNA of pathogenic L.interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai as the template,several PCRs were performed to amplify entire vapB,vapC and vapBC genes.Subsequently,the prokaryotic expression systems of vapB,vapC and vapBC genes were constructed.Expression of the target recombinant proteins rVapB and rVapC was detected by SDS-PAGE and the expressed rVapB and rVapC were extracted by NiNTA affinity chromatography.Activity of rVapB and rVapC to lyse the DNAs or RNAs from L.interrogans strain Lai and THP-1 cells were then determined.The changes of transcription and expression of vapB and vapC genes of L.interrogans strain Lai before and after infection of THP-1 cells were detected by real-time fluorescent quantitative RT-PCR and Western blot assay.The eukaryotic expression vectors of the vapB and vapC genes were generated for transfection of host cells and CCK-8 agent was used to detect the effect of leptospiral VapB and VapC proteins on activity of host cells.Results The nucleotide and putative amino acid sequences of the cloned vapB and vapC genes were completely identical with the reported corresponding genes.The constructed prokaryotic expression systems could express rVapB and rVapC,respectively.rVapC displayed RNase avtivity but did not lyse DNA.When L.interrogans strain Lai infected THP-1 cells,the transcription and expression of vapB and vapC genes were upregulated and partial VapC protein was secreted from the leptospiral cells.The mass mortality was observed in HEK293 human renal tubular epithelial ceils containing the vapC gene through transfection.Conclusion VapC protein of L.interrogans strain Lai is a RNase and is secreted during infection of host cells with obvious cytotoxicity.%目的 了解钩端螺旋体毒素-抗毒素系统中毒性蛋白VapC的

  6. Isolation of a Seawater Tolerant Leptospira spp. from a Southern Right Whale (Eubalaena australis.

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    Sylvia Grune Loffler

    Full Text Available Leptospirosis is the most widespread zoonotic disease in the world. It is caused by pathogenic spirochetes of the genus Leptospira spp. and is maintained in nature through chronic renal infection of carrier animals. Rodents and other small mammals are the main reservoirs. Information on leptospirosis in marine mammals is scarce; however, cases of leptospirosis have been documented in pinniped populations from the Pacific coast of North America from southern California to British Columbia. We report the isolation of a Leptospira spp. strain, here named Manara, from a kidney sample obtained from a Southern Right Whale (Eubalaena australis calf, which stranded dead in Playa Manara, Península Valdés, Argentina. This strain showed motility and morphology typical of the genus Leptospira spp. under dark-field microscopy; and grew in Ellinghausen-McCullough-Johnson-Harris (EMJH medium and Fletcher medium after 90 days of incubation at 28°C. Considering the source of this bacterium, we tested its ability to grow in Fletcher medium diluted with seawater at different percentages (1%, 3%, 5%, 7% and 10% v/v. Bacterial growth was detected 48 h after inoculation of Fletcher medium supplemented with 5% sea water, demonstrating the halophilic nature of the strain Manara. Phylogenetic analysis of 16S rRNA gene sequences placed this novel strain within the radiation of the pathogenic species of the genus Leptospira spp., with sequence similarities within the range 97-100%, and closely related to L. interrogans. Two different PCR protocols targeting genus-specific pathogenic genes (G1-G2, B64I-B64II and LigB gave positive results, which indicates that the strain Manara is likely pathogenic. Further studies are needed to confirm this possibility as well as determine its serogroup. These results could modify our understanding of the epidemiology of this zoonosis. Until now, the resistance and ability to grow in seawater for long periods of time had been proven

  7. Cross-Sectional Study of Leptospira Seroprevalence in Humans, Rats, Mice, and Dogs in a Main Tropical Sea-Port City

    Science.gov (United States)

    Romero-Vivas, Claudia M. E.; Cuello-Pérez, Margarett; Agudelo-Flórez, Piedad; Thiry, Dorothy; Levett, Paul N.; Falconar, Andrew K. I.

    2013-01-01

    Samples were collected from 128 symptomatic humans, 83 dogs, 49 mice, and 20 rats (Rattus rattus: 16; Rattus norvegicus: 4) in neighborhoods where human leptospirosis have been reported within the principal sea-port city of Colombia. Seroprevalences were assessed against 19 pathogenic, 1 intermediate pathogenic, and 1 saprophytic Leptospira serogroups. Pathogenic Leptospira were confirmed using conventional Leptospira-specific polymerase chain-reaction and pulsed-field gel electrophoresis analysis was used for serovar identification. Seroprevalences of 20.4%, 12.5%, 25.0%, 22.9%, and 12.4% were obtained against one to seven different serogroups in mice, R. rattus, R. norvegicus, dogs, and humans, respectively. The DNA was confirmed to be from pathogenic Leptospira by detecting the lipL32 gene in 12.5%, 3.7%, and 0.03% of the R. rattus, dog, and human samples, respectively. The first genetically typed Colombian isolate was obtained from a rat and identified as Leptospira interrogans serovar Icterohaemorrhagiae/Copenhageni. PMID:23149584

  8. Identification and Analysis of Genes Present in Leptospira interrogens serovar lai but Absent in L.biflexa serovar monvalerio

    Institute of Scientific and Technical Information of China (English)

    Ping HE; Xiang-Yan ZHANG; Xiao-Kui GUO; Bao-Yu HU; Xiao-Tian HUANG; Yang YANG; Guo-Ping ZHAO

    2004-01-01

    Genes present in virulent bacterial strains but absent in avirulent close relatives can be of great biologic and clinical interest. This project aimed to identify strain specific DNA sequences of Leptospira interrogens serovar lai, which is absent in the saprophytic L. biflexa serovar monvalerio, via suppression subtractive hybridization with the former as the tester while the latter as the driver. The mixture of PCR amplified DNA fragments from two subtractive hybridization experiments were cloned into pMD 18-T vector and the positive clones were identified by dot blotting against the chromosome DNA of the two strains individually. After DNA sequencing and analysis, the distribution of these genomic fragment sequences in a panel of pathogenic and nonpathogenic leptospires was investigated employing dot blot analysis. Among the 188 positive clones randomly chosen, 24 contained the tester strain specific genomic regions, of which, 5were non-coding fragments while the others contained 23 distinct protein coding sequences. Besides 9 genes encoding functional proteins, 12 genes encode unknown proteins and the rest two genes encode proteins with recognizable domain structures, one for a putative leucine-rich repeats (LRR) family protein while the other as an outer-membrane protein. Our experiment results indicated that suppression subtractive hybridization is effective for screening specific DNA sequences between two leptospiral strains, and some of these sequences might be responsible for virulence determination. Further analysis of these DNA sequences will provide important information on the pathogenesis of Leptospira.

  9. Caracterización molecular de serovariedades de Leptospira spp. aisladas de muestras de animales y agua en Colombia

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    Claudia M. Romero-Vivas

    2013-08-01

    Full Text Available Introducción. La leptospirosis es una infección bacteriana transmitida directa o indirectamente de animales a humanos, la cual puede resultar en una enfermedad hemorrágica grave, hepática o renal y pulmonar. Hay 20 especies de Leptospira conocidas y cientos de serovariedades, algunas de las cuales pertenecen a diferentes especies. Es esencial identificar las serovariedades patógenas y sus reservorios potenciales para enfocar estrategias de control. Objetivo. Caracterizar las serovariedades de Leptospira aisladas de muestras de roedores, perros, cerdos y agua en Colombia. Materiales y métodos. Las cepas de leptospiras aisladas fueron identificadas como patógenas usando la reacción en cadena de la polimerasa (PRC. Sus ADN y el ADN de Salmonella Braenderup H9812 (marcador de peso molecular fueron cortados con NotI y corridos en electroforesis de campo pulsado. Los patrones de la ECP se analizaron con base en los criterios de tipificación para cepas bacterianas y el coeficiente de Dice, cuando se compararon con 200 cepas aisladas en otras partes del mundo. Los perfiles de ADN con un coeficiente de Dice entre 73,7 % y 100 % se consideraron pertenecientes a la misma especie. Resultados. Todos los aislamientos fueron cepas patógenas y cinco se caracterizaron genéticamente. El aislamiento P275 (coeficiente de Dice: 84 % y el P282 (coeficiente de Dice: 95 % de cerdos, se relacionaron con Leptospira interrogans de serovariedad Pomona; el aislamiento de rata (I15 fue indistinguible de Leptospira interrogans de serovariedades Icterohaemorrhagiae o Copenhageni (coeficiente de Dice: 100 %, mientras que los aislamientos de perro (C67 y agua (A42 no se relacionaron (coeficiente de Dice <73,7 % con ninguna de las 200 cepas de referencia; las más cercanas fueron Leptospira noguchii de serovariedades Nicaragua (coeficiente de Dice: 63 % y Orleans (coeficiente de Dice: 60 %. Conclusiones. Esta fue la primera caracterización molecular de serotipos de

  10. Reporte de insuficiencia renal producida por Leptospira Interrogans Serovar Pomona en Colombia

    Directory of Open Access Journals (Sweden)

    Fortunato Ospino

    1988-06-01

    Full Text Available Se describe la presentación de un caso de leptospirosis producida por L. pomona en un paciente de 20 años de edad, trabajadora habitual en un molino de arroz y caracterizado por un síndrome de insuficiencia renal y hepática. El cuadro clínico consistió principalmente en malestar general, anorexia, vómito, fiebre, diarrea, ictericia y hemorragias subconjuntivales. Los exámenes de laboratorio mostraron alteraciones, en los niveles de nitrógeno ureico, creatinina, depuración de creatinina, concentración de cloro, fosfatasa alcalina y bilirrubina directa lo cual podría indicar un daño en el funcionamiento hepático y renal. Las alteraciones en la velocidad de sedimentación, hemoglobina, hematocrito y leucocitos (Tabla 1 explican la anemia e infección ocasionada por la L. pomona en la paciente. El diagnóstico de leptospirosis fue confirmado por el aislamiento del microorganismo de la orina a pesar de no haber detectado anticuerpos en el suero de la paciente. Se pone en evidencia la necesidad de realizar siempre el diagnóstico diferencial con leptospirosis en todo síndrome hepatorrenal, especialmente en los casos con antecedentes epidemiológicos o que por la sintomatología clínica se sospeche la infección.

  11. A dominant clone of Leptospira interrogans associated with an outbreak of human leptospirosis in Thailand

    National Research Council Canada - National Science Library

    Thaipadungpanit, Janjira; Wuthiekanun, Vanaporn; Chierakul, Wirongrong; Smythe, Lee D; Petkanchanapong, Wimol; Limpaiboon, Roongrueng; Apiwatanaporn, Apichat; Slack, Andrew T; Suputtamongkol, Yupin; White, Nicholas J; Feil, Edward J; Day, Nicholas P J; Peacock, Sharon J

    2007-01-01

    .... A prospective study was conducted between 2000 and 2005 to identify patients with leptospirosis presenting to Udon Thani Hospital in northeast Thailand, and to isolate the causative organisms from blood...

  12. Inmunogenicidad y capacidad protectora en hamsters de vacunas antileptospirósicas monovalentes de células enteras del serogrupo Ballum Immunogenicity and protective capacity of leptospiral whole-cell monovalent serogroup Ballum vaccines in hamsters

    Directory of Open Access Journals (Sweden)

    A. González

    2005-12-01

    Full Text Available El serogrupo Ballum de Leptospira constituye en la actualidad la primera causa de leptospirosis humana en Cuba. Vacunas de células enteras químicamente inactivadas fueron formuladas a partir de dos cepas clínicas de Leptospira interrogans serogrupo Ballum empleando como adyuvante hidróxido de aluminio. Los niveles de aglutininas inducidos en hamsters por una u otra preparación vacunal fueron estimados mediante aglutinación microscópica y la actividad IgG específica fue cuantificada mediante ELISA. La capacidad de protección homóloga y heteróloga contra la infección letal y subletal se determinó mediante el desafío con 100 y 10 000 DL50 de cinco cepas virulentas pertenecientes a los serogrupos Ballum, Canicola, Icterohaemorrhagiae y Pomona. Las evaluaciones realizadas demostraron que ambas vacunas fueron inmunogénicas e indujeron una completa protección homóloga en el modelo animal empleado. La protección cruzada frente a serogrupos heterólogos solo fue significativa en una de las preparaciones monovalentes frente al desafío con 100 DL50 de Canicola. Como resultado de este estudio se pudo comprobar la alta inmunogenicidad y capacidad protectora en hamsters de vacunas monovalentes de células enteras formuladas a partir de dos cepas candidatas vacunales del serogrupo de Leptospira de mayor circulación en humanos en Cuba no incluido en la vacuna actualmente disponible.Leptospira serogroup Ballum is at present the first cause of human leptospirosis in Cuba. Killed whole-cell vaccines were formulated with two clinical isolates of Leptospira interrogans serogroup Ballum using aluminum hydroxide as adjuvant. Agglutinins levels induced by each vaccine in hamsters were estimated by microscopic agglutination test and specific IgG activities were quantified by a whole cell-based enzyme-linked immunosorbent assay. Homologous and cross protective capacity against lethal and sublethal infection were determined in vaccinated animals by

  13. THE PERSISTENCE OF LEPTOSPIRAL AGGLUTININS TITERS IN HUMAN SERA DIAGNOSED BY THE MICROSCOPIC AGGLUTINATION TEST

    Directory of Open Access Journals (Sweden)

    Eliete C. ROMERO

    1998-05-01

    Full Text Available The persistence of agglutinins detected by MAT has created some problems to the interpretation of the results. The aim of this study was to examine the data of serology from 70 patients with serologically confirmed diagnosis of leptospirosis by during 3-13 months after being affected with leptospires in order to elucidate the interpretation of the persistence of agglutinins detected by MAT. Sixty-one patients sera (87.14% had titers equal or greater than 800. Of these, two individuals maintained titers of 800 thirteen months after the onset. This study showed that only one sample of sera with high titers is not reliable to determine the time at which infection occurred.Persistência de títulos de aglutininas anti-leptospiras em soros humanos diagnosticados pelo teste de aglutinação microscópica A persistência de aglutininas detectadas por MAT tem criado problemas na interpretação dos resultados. O objetivo deste trabalho foi examinar os resultados da sorologia de 70 pacientes com confirmação sorológica de leptospirose durante 3-13 meses após terem sido infectados para se poder elucidar a interpretação da persistência de aglutininas detectadas por MAT. Sessenta e um soros de pacientes (87,14% apresentaram títulos iguais, ou maiores, que 800. Destes, 2 indivíduos mantiveram títulos de 800 treze meses após terem sido infectados. Este estudo mostra que apenas uma amostra de soro, mesmo com alto título de aglutininas, não pode ser considerada para determinar a fase da doença.

  14. [Leptospiral antibodies in a Colombian zoo's neotropical primates and workers].

    Science.gov (United States)

    Romero, Marlyn H; Astudillo, Miryam; Sánchez, Jorge A; González, Lina M; Varela, Néstor

    2011-10-01

    Detecting antibodies against Leptospira spp. in Neotropical primates and workers in a Colombian Zoo and identifying the risk factors associated with the disease. A cross-sectional study was performed regarding 65 Neotropical primates and 20 zookeepers. The samples were processed by microagglutination test (MAT) using a reference strain collection consisting of 21 Leptospira serovars. The people being evaluated were given a structured survey to identify risk factors. There was 25 % (5/20) Leptospira spp. infection seroprevalence in the staff and 23.07 % (15/65) in Neotropical monkeys. The most frequently occurring serovars in workers were bataviae, gryppotyphosa and ranarum; icterohaemorrhagiae, pomona and ranarum were the predominant serovars in non-human primates. The black spider monkey (Ateles fusciceps), white-fronted capuchin (Cebus albifrons) and white-footed tamarin (Saguinus leucopus) showed the highest reactivity. Most of the personnel were using protective clothing. The contact between primates and zookeepers involving different Leptospira sp. serovars was evident. Zoo personnel using protective clothing and their length of experience were considered to be protective factors for the disease. There may be a risk of Leptospira transmission between zoo animals and staff, and it is therefore important to strengthen active surveillance and implement promotion and prevention programs.

  15. Feral Swine Leptospira Seroprevalence Survey in Hawaii, USA, 2007-2009.

    Science.gov (United States)

    Buchholz, A E; Katz, A R; Galloway, R; Stoddard, R A; Goldstein, S M

    2016-12-01

    Leptospirosis is considered the most widespread of zoonotic diseases. It was a notifiable disease in the United States until 1995 and was reinstated to the list of nationally notifiable diseases in 2014. During the time of national surveillance, Hawaii consistently led the nation in reported annual incidence rates. Leptospirosis has remained a reportable disease in Hawaii. Significant changes have been documented since the early 1970s in the predominant serogroup infecting humans in Hawaii: infections due to Icterohaemorrhagiae have declined while infections due to Australis have increased. A recent study from Hawaii demonstrated that Australis was an uncommon infecting serogroup for small mammal hosts. Swine have not been previously studied in Hawaii but are well-recognized maintenance hosts for leptospires belonging to the Australis serogroup. This study was undertaken to assess the prevalence of Leptospira antibody in feral swine in Hawaii. From January 2007 through December 2009, blood samples were collected opportunistically from feral swine. Using the microscopic agglutination test, we found antibody titres ≥1 : 100 to leptospires in 272 (33.8%) of 804 feral swine. The most frequently reacting serovars to the swine sera were Icterohaemorrhagiae (Icterohaemorrhagiae serogroup) (41.5%) and Bratislava (Australis serogroup) (33.8%). The high seroprevalence and presumptively infecting serovars suggest a link between swine and human infection. © 2016 Blackwell Verlag GmbH.

  16. Comparison of two multilocus sequence based genotyping schemes for Leptospira species.

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    Ahmed Ahmed

    2011-11-01

    Full Text Available BACKGROUND: Several sequence based genotyping schemes have been developed for Leptospira spp. The objective of this study was to genotype a collection of clinical and reference isolates using the two most commonly used schemes and compare and contrast the results. METHODS AND FINDINGS: A total of 48 isolates consisting of L. interrogans (n = 40 and L. kirschneri (n = 8 were typed by the 7 locus MLST scheme described by Thaipadungpanit et al., and the 6 locus genotyping scheme described by Ahmed et al., (termed 7L and 6L, respectively. Two L. interrogans isolates were not typed using 6L because of a deletion of three nucleotides in lipL32. The remaining 46 isolates were resolved into 21 sequence types (STs by 7L, and 30 genotypes by 6L. Overall nucleotide diversity (based on concatenated sequence was 3.6% and 2.3% for 7L and 6L, respectively. The D value (discriminatory ability of 7L and 6L were comparable, i.e. 92.0 (95% CI 87.5-96.5 vs. 93.5 (95% CI 88.6-98.4. The dN/dS ratios calculated for each locus indicated that none were under positive selection. Neighbor joining trees were reconstructed based on the concatenated sequences for each scheme. Both trees showed two distinct groups corresponding to L. interrogans and L. kirschneri, and both identified two clones containing 10 and 7 clinical isolates, respectively. There were six instances in which 6L split single STs as defined by 7L into closely related clusters. We noted two discrepancies between the trees in which the genetic relatedness between two pairs of strains were more closely related by 7L than by 6L. CONCLUSIONS: This genetic analysis indicates that the two schemes are comparable. We discuss their practical advantages and disadvantages.

  17. 9 CFR 113.101 - Leptospira Pomona Bacterin.

    Science.gov (United States)

    2010-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.101 Leptospira Pomona Bacterin. Leptospira Pomona Bacterin shall...

  18. 9 CFR 113.105 - Leptospira Hardjo Bacterin.

    Science.gov (United States)

    2010-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.105 Leptospira Hardjo Bacterin. Leptospira Hardjo Bacterin shall...

  19. 9 CFR 113.103 - Leptospira Canicola Bacterin.

    Science.gov (United States)

    2010-01-01

    ... AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.103 Leptospira Canicola Bacterin. Leptospira Canicola Bacterin shall...

  20. 9 CFR 113.104 - Leptospira Grippotyphosa Bacterin.

    Science.gov (United States)

    2010-01-01

    ... OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.104 Leptospira Grippotyphosa Bacterin. Leptospira...

  1. IDENTIFICATION OF PATHOGENIC LEPTOSPIRES BY RECOMBINANT DNA PROBES

    Institute of Scientific and Technical Information of China (English)

    戴保民; 肖建国; 沈成义

    1994-01-01

    Early diagnosis of leptospirosis of pulmonary diffuse bernorrhage type (PDH) is of crucial importance in saving patients. To develop a sensitive and specific method for diagnvsis, a genonlic library of the main pathogen of PDH, L. interogans serovar lai strath 017, was constructed with the plasmid vector pUC9. Recmbinant plasmids which have hornologotLq fragments of pathogenic inptospires were screened from the bank. A recombinant plasmid.designated pCX7, could detect 1. 7 kb fragment of strain 017. 9. 0 kb of strain 601 and 30. 0 kb of strain Hebdo-maclis, respectively, without cross hybridization with nonpathogcnic leptospires such as L. biflexa strain Patoc 1 and Leptonema illini. The recombinant plasmid pCX7 could detect pathogenic leptospires which are the main pathogens endemic to Sichuan Province.

  2. Risk of infection and associated influenza-like disease among abattoir workers due to two Leptospira species.

    Science.gov (United States)

    Dreyfus, A; Heuer, C; Wilson, P; Collins-Emerson, J; Baker, M G; Benschop, J

    2015-07-01

    The aims of this study were to determine the annual incidence of infection with Leptospira interrogans serovar Pomona and/or Leptospira borgpetersenii serovar Hardjo and its association with influenza-like illness (ILI) in meat workers in New Zealand. Sera were collected twice, 50-61 weeks apart, from 592 workers at eight abattoirs slaughtering sheep (n = 4), cattle (n = 2) and deer (n = 2), and tested by the microscopic agglutination test for Hardjo and Pomona. Forty-nine (8·3%) participants either seroconverted or had at least a twofold increased serological titre against either serovar. The worker infection risk was higher in sheep abattoirs (11·9%) than in abattoirs processing deer (0%) or cattle (1·2%) (P Leptospira serovars was 2·7%. This study has demonstrated that meat workers are at substantial risk of infection and clinical disease, suggesting further investigation of infection sources and preventive measures are warranted.

  3. A comparison of three DNA extractive procedures with Leptospira for polymerase chain reaction analysis

    Directory of Open Access Journals (Sweden)

    Veloso IF

    2000-01-01

    Full Text Available Three DNA extraction methods were evaluated in this study: proteinase K followed by phenol-chloroform; a plant proteinase (E6870 followed by phenol-chloroform; and boiling of leptospires in 0.1 mM Tris, pH 7.0 for 10 min at 100°C, with no phenol treatment. Every strain treated with proteinase K or E6870 afforded positive polymerase chain reaction (PCR reaction. On the other hand, from five strains extracted by the boiling method, three did not feature the 849 bp band characteristic in Leptospira. We also evaluated by RAPD-PCR, DNAs from serovars isolated with proteinase K and proteinase 6870 with primers B11/B12. Each of the DNA samples provided PCR profiles in agreement with previous data. Moreover, the results with E6870 showed less background non-specific amplification, suggesting that removal of nucleases was more efficient with E6870. The limit for detection by PCR using Lep13/Lep14 was determined to be 10(2 leptospira, using the silver stain procedure.

  4. A quantitative PCR (TaqMan assay for pathogenic Leptospira spp

    Directory of Open Access Journals (Sweden)

    Symonds Meegan L

    2002-07-01

    Full Text Available Abstract Background Leptospirosis is an emerging infectious disease. The differential diagnosis of leptospirosis is difficult due to the varied and often "flu like" symptoms which may result in a missed or delayed diagnosis. There are over 230 known serovars in the genus Leptospira. Confirmatory serological diagnosis of leptospirosis is usually made using the microscopic agglutination test (MAT which relies on the use of live cultures as the source of antigen, often performed using a panel of antigens representative of local serovars. Other techniques, such as the enzyme linked immunosorbent assay (ELISA and slide agglutination test (SAT, can detect different classes of antibody but may be subject to false positive reactions and require confirmation of these results by the MAT. Methods The polymerase chain reaction (PCR has been used to detect a large number of microorganisms, including those of clinical significance. The sensitivity of PCR often precludes the need for isolation and culture, thus making it ideal for the rapid detection of organisms involved in acute infections. We employed real-time (quantitative PCR using TaqMan chemistry to detect leptospires in clinical and environmental samples. Results and Conclusions The PCR assay can be applied to either blood or urine samples and does not rely on the isolation and culture of the organism. Capability exists for automation and high throughput testing in a clinical laboratory. It is specific for Leptospira and may discriminate pathogenic and non-pathogenic species. The limit of detection is as low as two cells.

  5. Arbitrarily primed PCR- A rapid and simple method for typing of leptospiral serovars

    Directory of Open Access Journals (Sweden)

    Ramadass P

    2002-01-01

    Full Text Available PURPOSE: To investigate the use of arbitrarily primed polymerase chain reaction (AP-PCR for typing of leptospiral serovars. METHODS: AP-PCR was adopted for identification of laboratory strains of leptospires and leptospiral cultures at serovar level. A primer of 12 bp was used for amplifying DNA of 13 laboratory strains of leptospires as well as culture pellets of leptospires. RESULTS: Each serovar produced distinct DNA fingerprint which was characteristic for each serovar. These patterns were used for typing of 81 serum culture samples obtained from human leptospiral cases. Of these samples, 39 could be typed based on AP-PCR fingerprints belonging to serovars autumnalis, pomona, canicola, javanica, icterohaemorrhagiae, patoc and pyrogenes. These results were confirmed by RAPD fingerprinting of the DNA samples of the respective leptospiral serovars after culturing -FNx01them in EMJH media. One of the important findings of this work was that straight culture sample could be used for AP-PCR assay, without purification of DNA. By having more number of AP-PCR reference fingerprints, more serovars could be typed. CONCLUSIONS: AP-PCR technique provides great potential for simple and rapid identification of leptospires at serovar level, which could be useful in molecular epidemiological studies of leptospirosis.

  6. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Directory of Open Access Journals (Sweden)

    Gauthier Dobigny

    Full Text Available Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings.

  7. Urban Market Gardening and Rodent-Borne Pathogenic Leptospira in Arid Zones: A Case Study in Niamey, Niger.

    Science.gov (United States)

    Dobigny, Gauthier; Garba, Madougou; Tatard, Caroline; Loiseau, Anne; Galan, Max; Kadaouré, Ibrahima; Rossi, Jean-Pierre; Picardeau, Mathieu; Bertherat, Eric

    2015-01-01

    Leptospirosis essentially affects human following contact with rodent urine-contaminated water. As such, it was mainly found associated with rice culture, recreational activities and flooding. This is also the reason why it has mainly been investigated in temperate as well as warm and humid regions, while arid zones have been only very occasionally monitored for this disease. In particular, data for West African countries are extremely scarce. Here, we took advantage of an extensive survey of urban rodents in Niamey, Niger, in order to look for rodent-borne pathogenic Leptospira species presence and distribution across the city. To do so, we used high throughput bacterial 16S-based metabarcoding, lipL32 gene-targeting RT-PCR, rrs gene sequencing and VNTR typing as well as GIS-based multivariate spatial analysis. Our results show that leptospires seem absent from the core city where usual Leptospira reservoir rodent species (namely R. rattus and M. natalensis) are yet abundant. On the contrary, L. kirschneri was detected in Arvicanthis niloticus and Cricetomys gambianus, two rodent species that are restricted to irrigated cultures within the city. Moreover, the VNTR profiles showed that rodent-borne leptospires in Niamey belong to previously undescribed serovars. Altogether, our study points towards the importance of market gardening in maintain and circulation of leptospirosis within Sahelian cities. In Africa, irrigated urban agriculture constitutes a pivotal source of food supply, especially in the context of the ongoing extensive urbanization of the continent. With this in mind, we speculate that leptospirosis may represent a zoonotic disease of concern also in arid regions that would deserve to be more rigorously surveyed, especially in urban agricultural settings.

  8. [The isolation and differentiation of leptospires from cattle drinking water].

    Science.gov (United States)

    Luyven, G; Schönberg, A

    1989-08-01

    The cultural isolation and identification of leptospires from three water samples of farm wells were described. All three strains isolated belong to the apathogenic species L. biflexa. The cattle stock of these farms (A, B, C) had reacted serologically to serovars hardjo and grippotyphosa. The strain isolated from farm A is a new serovar called krefeldi and belongs to serogroup Doberdo. The strain isolated from farm B belongs to serovar montefiascone of serogroup Botanica and the strain from farm C to serovar bessemans of serogroup Bessemans. It is remarkable that serovar krefeldi with all the sera of farm A (titre up to 1:40) and only with part of the sera of farm B reacted.

  9. Newly recognized Leptospira species ("Leptospira inadai" serovar lyme) isolated from human skin.

    Science.gov (United States)

    Schmid, G P; Steere, A C; Kornblatt, A N; Kaufmann, A F; Moss, C W; Johnson, R C; Hovind-Hougen, K; Brenner, D J

    1986-01-01

    Leptospira strain 10, which represents a new Leptospira species, was isolated from a skin biopsy of a patient with Lyme disease. Although pathogenic for laboratory animals, the organism was not considered to have a significant role in the patient's illness. PMID:3760144

  10. Leptospires Are Killed In Vitro by Both Oxygen-Dependent and -Independent Reactions

    OpenAIRE

    Murgia, Rossella; Garcia, Rodolfo; Cinco, Marina

    2002-01-01

    This study reports for the first time that leptospires are killed by H2O2 and by low-molecular-weight primary granule components, which are agents normally released by neutrophils upon stimulation. Although both pathogenic and nonpathogenic strains were sensitive to H2O2-mediated killing, nonpathogenic organisms were found to be more susceptible. In addition, the killing of leptospires by H2O2 was found to be independent of the presence of the neutrophil primary granule component myeloperoxid...

  11. Seroprevalence of Leptospiral Antibodies among Healthy Municipal Service Workers in Selangor

    Directory of Open Access Journals (Sweden)

    Suhailah Samsudin

    2015-01-01

    Full Text Available Introduction. Municipal service workers have been found to have an occupational risk of leptospirosis. Study among municipality workers shows high seropositivity of leptospiral antibodies detected among town cleaners and garbage collectors. Objective. Aims of this study were to determine seroprevalence of leptospiral antibodies and distribution of serovars detected in samples among municipal service workers. Methodology. Cross-sectional study involved 89 municipal service workers in Selangor. Blood samples were taken and serological test was done using MAT following standard procedures. Results. Seropositivity of leptospiral antibodies among municipal service workers was 34.8%. Serovars identified were strains of Sarawak, Copenhageni, Hardjobovis, Lai, Bataviae, Patoc, Celledoni, Hardjoprajitno, Tarrasovi, and Pomona. There were 31 workers with positive leptospiral antibodies. All of them were frequently exposed towards leptospirosis. Significant associations have been reported between seropositivity of leptospiral antibodies with job category (P=0.021 and worker’s nationality (P=0.014 among municipal service workers. Conclusion. High seropositivity of leptospiral antibodies detected among municipal service workers which was associated with job category and nationality of workers. The significant findings from this study suggest that health education programs and safe work practice should be considered to prevent leptospirosis among municipal service workers in future.

  12. Characterization of the Bat proteins in the oxidative stress response of Leptospira biflexa

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    Stewart Philip E

    2012-12-01

    Full Text Available Abstract Background Leptospires lack many of the homologs for oxidative defense present in other bacteria, but do encode homologs of the Bacteriodes aerotolerance (Bat proteins, which have been proposed to fulfill this function. Bat homologs have been identified in all families of the phylum Spirochaetes, yet a specific function for these proteins has not been experimentally demonstrated. Results We investigated the contribution of the Bat proteins in the model organism Leptospira biflexa for their potential contributions to growth rate, morphology and protection against oxidative challenges. A genetically engineered mutant strain in which all bat ORFs were deleted did not exhibit altered growth rate or morphology, relative to the wild-type strain. Nor could we demonstrate a protective role for the Bat proteins in coping with various oxidative stresses. Further, pre-exposing L. biflexa to sublethal levels of reactive oxygen species did not appear to induce a general oxidative stress response, in contrast to what has been shown in other bacterial species. Differential proteomic analysis of the wild-type and mutant strains detected changes in the abundance of a single protein only – HtpG, which is encoded by the gene immediately downstream of the bat loci. Conclusion The data presented here do not support a protective role for the Leptospira Bat proteins in directly coping with oxidative stress as previously proposed. L. biflexa is relatively sensitive to reactive oxygen species such as superoxide and H2O2, suggesting that this spirochete lacks a strong, protective defense against oxidative damage despite being a strict aerobe.

  13. Genetic affinities within a large global collection of pathogenic Leptospira: implications for strain identification and molecular epidemiology.

    Directory of Open Access Journals (Sweden)

    Kishore Nalam

    Full Text Available Leptospirosis is an important zoonosis with widespread human health implications. The non-availability of accurate identification methods for the individualization of different Leptospira for outbreak investigations poses bountiful problems in the disease control arena. We harnessed fluorescent amplified fragment length polymorphism analysis (FAFLP for Leptospira and investigated its utility in establishing genetic relationships among 271 isolates in the context of species level assignments of our global collection of isolates and strains obtained from a diverse array of hosts. In addition, this method was compared to an in-house multilocus sequence typing (MLST method based on polymorphisms in three housekeeping genes, the rrs locus and two envelope proteins. Phylogenetic relationships were deduced based on bifurcating Neighbor-joining trees as well as median joining network analyses integrating both the FAFLP data and MLST based haplotypes. The phylogenetic relationships were also reproduced through Bayesian analysis of the multilocus sequence polymorphisms. We found FAFLP to be an important method for outbreak investigation and for clustering of isolates based on their geographical descent rather than by genome species types. The FAFLP method was, however, not able to convey much taxonomical utility sufficient to replace the highly tedious serotyping procedures in vogue. MLST, on the other hand, was found to be highly robust and efficient in identifying ancestral relationships and segregating the outbreak associated strains or otherwise according to their genome species status and, therefore, could unambiguously be applied for investigating phylogenetics of Leptospira in the context of taxonomy as well as gene flow. For instance, MLST was more efficient, as compared to FAFLP method, in clustering strains from the Andaman island of India, with their counterparts from mainland India and Sri Lanka, implying that such strains share genetic

  14. HISTOPATHOLOGY of Rattusattus norvegicus KIDNEY INFECTED by Leptospira = GAMBARAN HISTOPATOLOGI GINJAL Rattus norvegicus INFEKTIF LEPTOSPIRA

    Directory of Open Access Journals (Sweden)

    Arief Mulyono

    2014-10-01

    Full Text Available ENGLISHAbstractA study on the histological structure of Rattus norvegicus kidney infected by Leptospira has been conducted. The purpose of this study was to determine the change of kidney tissue structure of R. norvegicus due to the patogenicity of Leptospira bacteria. The study was done in Miroto, Central Semarang District, Semarang Municipality. Rattus norvegicus was caught with live trap. The blood and kidney specimen were taken from all the caught rat. Then the blood was serologically examined by using Leptotek Dri-Dot, whereas the kidney was histopatologically observed under the microscope by using Hematoxylin-Eosin staining. The data were collected qualitatively and then analyzed descriptively by describing histological kidney appearance of R. norvegicus which were infected by Leptospira. The results of this research showed that 11 individuals of R. norvegicus caught and 8 induvidual infected by Leptospira. The results of R. norvegicus histological kidney examination which were infected by Leptospira show capillaries dilatation and hyalinization in glomerulus.INDONESIANTelah dilakukan penelitian tentang struktur histopalogi organ ginjal tikus got (Rattus norvegicus terinfeksi Leptospira. Tujuan penelitian untuk mengetahui perubahan struktur jaringan ginjal R. norvegicus akibat patogenitas bakteri Leptospira. Penelitian dilakukan di kelurahan Miroto, Kecamatan Semarang Tengah, Kota Semarang. Rattus norvegicus ditangkap dengan perangkap dan tikus tertangkap diambil spesimen darah dan ginjal. Darah diperiksa secara serologis dengan Leptotek Dri-Dot. Sedangkan ginjal diperiksa secara histopatologis dengan pewarnaan Haemotoxylin-Eosin dan diperiksa di bawah mikroskop. Jumlah R. norvegicus yang tertangkap dan diperiksa sebanyak 11 ekor. Pemeriksaan serologi menunjukkan R. norvegicus infektif Leptospira sebanyak 8 ekor. Hasil pemeriksaan histopatologis ginjal R. norvegicus terinfeksi Leptospira, menunjukkan terjadinya perubahan struktur berupa

  15. Para-(benzoyl)-phenylalanine as a potential inhibitor against LpxC of Leptospira spp.: homology modeling, docking, and molecular dynamics study.

    Science.gov (United States)

    Pradhan, Dibyabhaba; Priyadarshini, Vani; Munikumar, Manne; Swargam, Sandeep; Umamaheswari, Amineni; Bitla, Aparna

    2014-01-01

    Leptospira interrogans, a Gram-negative bacterial pathogen is the main cause of human leptospirosis. Lipid A is a highly immunoreactive endotoxic center of lipopolysaccharide (LPS) that anchors LPS into the outer membrane of Leptospira. Discovery of compounds inhibiting lipid-A biosynthetic pathway would be promising for dissolving the structural integrity of membrane leading to cell lysis and death of Leptospira. LpxC, a unique enzyme of lipid-A biosynthetic pathway was identified as common drug target of Leptospira. Herein, homology modeling, docking, and molecular dynamics (MD) simulations were employed to discover potential inhibitors of LpxC. A reliable tertiary structure of LpxC in complex with inhibitor BB-78485 was constructed in Modeller 9v8. A data-set of BB-78485 structural analogs were docked with LpxC in Maestro v9.2 virtual screening workflow, which implements three stage Glide docking protocol. Twelve lead molecules with better XP Gscore compared to BB-78485 were proposed as potential inhibitors of LpxC. Para-(benzoyl)-phenylalanine - that showed lowest XP Gscore (-10.35 kcal/mol) - was predicted to have best binding affinity towards LpxC. MD simulations were performed for LpxC and para-(benzoyl)-phenylalanine docking complex in Desmond v3.0. Trajectory analysis showed the docking complex and inter-molecular interactions was stable throughout the entire production part of MD simulations. The results indicate para-(benzoyl)-phenylalanine as a potent drug molecule against leptospirosis. An animated Interactive 3D Complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:10.

  16. Application and validation of PFGE for serovar identification of Leptospira clinical isolates.

    Directory of Open Access Journals (Sweden)

    Renee L Galloway

    Full Text Available Serovar identification of clinical isolates of Leptospira is generally not performed on a routine basis, yet the identity of an infecting serovar is valuable from both epidemiologic and public health standpoints. Only a small number of reference laboratories worldwide have the capability to perform the cross agglutinin absorption test (CAAT, the reference method for serovar identification. Pulsed-field gel electrophoresis (PFGE is an alternative method to CAAT that facilitates rapid identification of leptospires to the serovar level. We employed PFGE to evaluate 175 isolates obtained from humans and animals submitted to the Centers for Disease Control and Prevention (CDC between 1993 and 2007. PFGE patterns for each isolate were generated using the NotI restriction enzyme and compared to a reference database consisting of more than 200 reference strains. Of the 175 clinical isolates evaluated, 136 (78% were identified to the serovar level by the database, and an additional 27 isolates (15% have been identified as probable new serovars. The remaining isolates yet to be identified are either not represented in the database or require further study to determine whether or not they also represent new serovars. PFGE proved to be a useful tool for serovar identification of clinical isolates of known serovars from different geographic regions and a variety of different hosts and for recognizing potential new serovars.

  17. Seroprevalence of Leptospira spp. in clinically healthy racing horses in Korea.

    Science.gov (United States)

    Jung, Byeong Yeal; Lee, Kyung Woo; Ha, Tae Young

    2010-02-01

    Leptospirosis is a zoonotic disease of global importance, and has a worldwide distribution. The present study aimed to determine leptospiral seroprevalence in clinically healthy racing horses from all three racecourses in Korea. Serum samples from 1,226 racing horses were examined using a microscopic agglutination test to detect the presence of antibodies against 18 Leptospira serovars. Of the tested samples, 307 (25.0%) were found to be positive. The distribution of seroprevalence differed significantly by racecourse (P=0.004); the Jeju course had the highest incidence (31.1%), followed by the Seoul (25.2%) and Busan (19.5%) racecourses. Seasonal variation in seropositivity was also apparent (P=0.000), being lower in spring (13.0%) and winter (12.5%), and higher in summer (36.7%) and autumn (34.7%). No significant age- or gender-related difference in seroprevalence was noted in this study (P>0.05). Seroprevalence was higher (P=0.006) among ponies than among thoroughbreds. Sejroe was the most frequently detected serovar (n=236), followed by Bratislava (n=35), Ballum (n=16), Autumnalis (n=10), and Canicola (n=10). The majority of serum titers were relatively low; most values ranged from 1:100 (n=217) to 1:200 (n=69). These results suggest that the Sejroe serovar may be maintained in the racing horse population in Korea.

  18. Identification of Leptospira spp. carriers among seroreactive goats and sheep by polymerase chain reaction.

    Science.gov (United States)

    Lilenbaum, W; Varges, R; Ristow, P; Cortez, A; Souza, S O; Richtzenhain, L J; Vasconcellos, S A

    2009-08-01

    Few studies were conducted on the diagnosis and control of small ruminants' leptospirosis. Thirteen goat herds and seven sheep flocks located in the state of Rio de Janeiro, Brazil, were screened for leptospirosis. From the three herds and three flocks with greatest seroreactivity by MAT (Microscopic Agglutination Test), 19 and 40 seropositive goats and sheep, respectively, were selected, and urine samples were collected for bacteriology and PCR. For both species of animals, the most prevalent reactions were due to serogroups Sejroe and Shermani. Although leptospires were observed by darkfield microscopy in eight samples, pure isolates were obtained by bacteriological culture from only two samples. However, twelve urine samples (six goats and six sheep) were positive by PCR. Based on these findings, we consider that the combined use of MAT as a screening test followed by urine PCR for the direct detection of Leptospira spp. DNA was adequate for the identification of carrier animals among goats and sheep. These are valuable tools for the control of leptospirosis in small ruminants.

  19. Circulating serovars of Leptospira in cart horses of central and southern Ethiopia and associated risk factors.

    Science.gov (United States)

    Tsegay, K; Potts, A D; Aklilu, N; Lötter, C; Gummow, B

    2016-03-01

    Little work has been done on diseases of horses in Ethiopia or tropical regions of the world. Yet, Ethiopia has the largest horse population in Africa and their horses play a pivotal role in their economy as traction animals. A serological and questionnaire survey was therefore conducted to determine the circulating serovars of Leptospira and their association with potential risk factors in the cart horse population of Central and Southern Ethiopia. A total of 184 out of 418 cart horses from 13 districts had antibody titres of 1:100 or greater to at least one of 16 serovars of Leptospira species in Central and Southern Ethiopian horses. A significantly higher seropositivity (62.1%) was noted in horses from the highland agroecology followed by midland (44.4%) and lowland (39.8%). Serovar Bratislava (34.5%) was the predominant serovar followed by serovars Djasiman (9.8%), Topaz (5.98%) and Pomona (5.3%). Age and location proved to be associated with seropositive horses with older horses being more commonly affected and the districts of Ziway (Batu) (Apparent Prevalence (AP)=65.5%), Shashemene (AP=48.3%) and Sebeta (AP=41.4%) having the highest prevalence. Multivariable logistic regression found risk factors significantly associated with Leptospira seropositive horses were drinking river water (OR=2.8) and horses 7-12 years old (OR=5) and risk factors specifically associated with serovar Bratislava seropositive horses were drinking river water (OR=2.5), horses ≥13 years (OR=3.5) and the presence of dogs in adjacent neighbouring properties (OR=0.3). Dogs had a protective effect against seropositivity to serovars Bratislava and Djasiman, which may be due to their ability to control rodents. The high seroprevalence confirm that leptospirosis is endemic among horses of Central and Southern Ethiopia. The predominance of serovar Bratislava supports the idea that serovar Bratislava may be adapted to and maintained by the horse population of Central and Southern Ethiopia

  20. Isolation of Leptospira noguchii from sheep.

    Science.gov (United States)

    Silva, Everton F; Brod, Claudiomar S; Cerqueira, Gustavo M; Bourscheidt, Débora; Seyffert, Núbia; Queiroz, Adriano; Santos, Cleiton S; Ko, Albert I; Dellagostin, Odir A

    2007-03-31

    The main goal of this study was to obtain new isolates of Leptospira spp. from sheep. A total of 10 kidney samples and 44 blood samples were collected from sheep slaughtered in Pelotas, Southern Brazil. One isolate was obtained which was identified by 16S rRNA gene sequencing and serogrouping to be Leptospira noguchii serogroup Autumnalis. Microscopic agglutination test (MAT) evaluation revealed that 4.5% of the sheep sera reacted against the Autumnalis serogroup. This is the first report of isolation of L. noguchii from sheep. Together these findings indicate that L. noguchii infections may be a potentially important veterinary problem in this domestic animal species.

  1. Fatal Septicemic Melioidosis in a Young Military Person Possibly Co-Infected With Leptospira Interrogans and Orientia Tsutsugamushi

    Directory of Open Access Journals (Sweden)

    Po-Liang Lu

    2005-04-01

    Full Text Available Concurrent melioidosis, leptospirosis, and scrub typhus after rural activities is rarely reported. A 19-year-old previously healthy man had fever onset after 2 weeks of military training. Pneumonia became evident on the fifth day of fever under intravenous penicillin and oral minocycline therapy. Acute respiratory failure developed the next day with shock and acute renal and liver function deterioration, which resulted in death. Blood cultures on the third and fifth days grew Burkholderia pseudomallei. Serology revealed leptospirosis and scrub typhus. The emergence of melioidosis in Taiwan and this death without antibiotic treatment for melioidosis alert us that B. pseudomallei should be included as a possible pathogen of pneumonia and sepsis, especially after rural activities.

  2. Immune response and protective profile elicited by a multi-epitope chimeric protein derived from Leptospira interrogans

    Directory of Open Access Journals (Sweden)

    Luis G.V. Fernandes

    2017-04-01

    Conclusions: Although a complete characterization of the immune response elicited by rChi/adjuvant in hamsters is required, it is believed that the construction of chimeric genes is an important attempt towards the generation of an effective vaccine against leptospirosis.

  3. Cinética da resposta imune humoral de cães jovens imunizados contra Leptospira interrogans

    National Research Council Canada - National Science Library

    Castro, Jacqueline R; Souza, Mariana A; Salaberry, Sandra R.S; Guimarães, Ednaldo C; Lima-Ribeiro, Anna M.C

    2011-01-01

    ... a utilização da prova de soroaglutinação microscópica (SAM) em 26 cães jovens, sendo 17 de raça definida (Grupo A) e nove sem raça (Grupo B), de ambos os sexos, pertencentes a canis e ambientes domiciliares...

  4. Identification of seroreactive proteins of Leptospira interrogans serovar copenhageni using a high-density protein microarray approach

    OpenAIRE

    Lessa-Aquino, Carolina; Rodrigues, Camila Borges; Ribeiro, Guilherme S. et al.

    2013-01-01

    Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. Methodology: In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Le...

  5. Identification of seroreactive proteins of Leptospira interrogans Serovar Copenhageni using a High-Density protein Microarray approach

    OpenAIRE

    Aquino, Carolina Lessa; Rodrigues, Camila Borges; Pablo, Jozelyn; Sasaki, Rie; Jasinskas, Algis; Guilherme S Ribeiro; Vigil, Adam

    2013-01-01

    p. 1-13 Background: Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. Methodology: In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip ...

  6. Identification of seroreactive proteins of Leptospira interrogans Serovar Copenhageni using a high-density protein microarray approach.

    OpenAIRE

    Ribeiro, Guilherme S. et al.

    2015-01-01

    Background: Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease. Methodology: In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein m...

  7. Leptospires in field Rats in and around the laboratory animal facilities of Banglore, India

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    G. Vinodkumar

    Full Text Available The present study was undertaken to determine the prevalence of leptospires in field rats in and around laboratory animal facilities in Bangalore. 34 rats were trapped alive in and around the laboratory animal facilities in Bangalore. Urine and serum samples from theses field rats were collected. Serum samples were tested for anti-leptospiral antibodies by microscopic agglutination test, while urine samples were subjected for dark field microscopy and polymerase chain reaction to detect the presence of leptospiral antigens. Serology revealed the presence of antileptospiral antibodies in 19 (61.29 percent field rats and dark field microscopy revealed the presence of leptospiral antigens in 3 (8.82 percent and 6 (17.65 percent of urine samples of these field rats. Among the serovars, Icterohaemorrhagiae was predominant followed by Autumnalis and Pyrogens. Serology dark field microscopy and polymerase chain reaction reveals that field rats are major natural carriers and shedders of leptospires. [Vet. World 2011; 4(9.000: 410-412

  8. The role of fruit bats in the transmission of pathogenic leptospires in Australia

    DEFF Research Database (Denmark)

    Tulsiani, Suhella; Cobbold, R N; Graham, G C

    2011-01-01

    Although antileptospiral antibodies and leptospiral DNA have been detected in Australian fruit bats, the role of such bats as infectious hosts for the leptospires found in rodents and humans remains unconfirmed. A cohort-design, replicated survey was recently conducted in Far North Queensland......, Australia, to determine if the abundance and leptospiral status of rodents were affected by association with colonies of fruit bats (Pteropus conspicillatus spp.) via rodent contact with potentially infectious fruit-bat urine. In each of four study areas, a 'colony site' that included a fruit-bat colony...... and the land within 1500 m of the colony was compared with a 'control site' that held no fruit-bat colonies and was >2000 m from the nearest edge of the colony site. Rodents were surveyed, for a total of 2400 trap-nights, over six sampling sessions between September 2007 and September 2008. A low abundance...

  9. Leptospires are killed in vitro by both oxygen-dependent and -independent reactions.

    Science.gov (United States)

    Murgia, Rossella; Garcia, Rodolfo; Cinco, Marina

    2002-12-01

    This study reports for the first time that leptospires are killed by H(2)O(2) and by low-molecular-weight primary granule components, which are agents normally released by neutrophils upon stimulation. Although both pathogenic and nonpathogenic strains were sensitive to H(2)O(2)-mediated killing, nonpathogenic organisms were found to be more susceptible. In addition, the killing of leptospires by H(2)O(2) was found to be independent of the presence of the neutrophil primary granule component myeloperoxidase and therefore not a consequence of halogenation reactions. We have also determined that leptospires are significantly sensitive only to primary granule components and, among those, to proteins and/or peptides of less than 30 kDa.

  10. Leptospira Infections in Trappers from Ontario

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    Bryna Warshawsky

    2000-01-01

    Full Text Available BACKGROUND: Four trappers presented to the Middlesex-London Health Unit in November, 1997 with similar clinical presentations. All four complained of fever, chills and headache, and three of the four had severe muscle aches. All gave histories of trapping raccoons before the onset of illness. Three of the four men exhibited diagnostic seroconversions to Leptospira grippotyphosa.

  11. Haemoglobin and red cell counts in leptospirosis patients infected with different serovars

    Directory of Open Access Journals (Sweden)

    Scott Benjamin Craig

    2013-04-01

    Full Text Available Introduction The aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars. Methods The study retrospectively compared the haemoglobin and red cell count results from the first blood samples taken from 207 patients at presentation to a Queensland Health hospital. Results Significant differences were observed in haemoglobin and red cell counts in those infected with Leptospira interrogans serovars Szwajizak and Canicola when compared with most of the other serovars. Conclusions These findings suggest that haemoglobin and red cell counts may be useful in differentiating leptospiral serovars in leptospirosis patients.

  12. Comparison of polymerase chain reaction and Warthin-Starry techniques to detect Leptospira spp. in kidneys of slaughtered cattle

    Directory of Open Access Journals (Sweden)

    Shahrzad Azizi

    2014-02-01

    Full Text Available Leptospirosis is a worldwide zoonotic disease that is caused by Gram-negative spirochaetes, Leptospira species. Affected animals excrete the organism in the urine into the environment and act as a source of infection. Cattle are maintenance hosts for some serovars of leptospirosis and are important in the transmission of the infection to humans. At post mortem examination, affected cattle show white spots in their kidneys but these are not specific for leptospirosis. Sometimes it is necessary that leptospirosis be diagnosed in the carcass. Different direct methods, including polymerase chain reaction (PCR, Warthin-Starry silver stain (WS, immunofluorescence (IF and immunohistochemistry (IHC can be used in order to diagnose leptospirosis in the affected tissues, such as kidney. The main advantage of the WS technique is direct visualisation of the bacteria in the tissue samples. Silver staining is useful for retrospective studies on formalin-fixed and paraffin-embedded samples but little information is available on the sensitivity and specificity of the technique. The present study aimed to find a simple and inexpensive method that can be used in any laboratory and that also, if clinical samples are not available, can detect Leptospira in tissue samples post mortem. This study was performed on 19 paraffin-embedded kidneys of slaughtered cows that grossly had focal to multifocal white spots. Leptospirosis was confirmed in these samples with PCR based on the LipL32 gene. Out of 19 PCR positive kidneys, Leptospira was identified in 13 stained samples by WS. The kidneys revealed different grades of interstitial nephritis. No relationship was found between severity of lesions and presence of leptospires in the kidneys. The PCR results on the urine and blood were consistent with matching WS stained kidneys. Out of 13 kidneys that were positive with silver staining, 7 matching blood and 10 matching urine samples were confirmed positive for leptospirosis

  13. Comparison of polymerase chain reaction and Warthin-Starry techniques to detect Leptospira spp. in kidneys of slaughtered cattle.

    Science.gov (United States)

    Azizi, Shahrzad; Kheirandish, Reza; Rahimi, Elham

    2014-11-12

    Leptospirosis is a worldwide zoonotic disease that is caused by Gram-negative spirochaetes, Leptospira species. Affected animals excrete the organism in the urine into the environment and act as a source of infection. Cattle are maintenance hosts for some serovars of leptospirosis and are important in the transmission of the infection to humans. At post mortem examination, affected cattle show white spots in their kidneys but these are not specific for leptospirosis. Sometimes it is necessary that leptospirosis be diagnosed in the carcass. Different direct methods, including polymerase chain reaction (PCR), Warthin-Starry silver stain (WS), immunofluorescence (IF) and immunohistochemistry (IHC) can be used in order to diagnose leptospirosis in the affected tissues, such as kidney. The main advantage of the WS technique is direct visualisation of the bacteria in the tissue samples. Silver staining is useful for retrospective studies on formalin-fixed and paraffin-embedded samples but little information is available on the sensitivity and specificity of the technique. The present study aimed to find a simple and inexpensive method that can be used in any laboratory and that also, if clinical samples are not available, can detect Leptospira in tissue samples post mortem. This study was performed on 19 paraffin-embedded kidneys of slaughtered cows that grossly had focal to multifocal white spots. Leptospirosis was confirmed in these samples with PCR based on the LipL32 gene. Out of 19 PCR positive kidneys, Leptospira was identified in 13 stained samples by WS. The kidneys revealed different grades of interstitial nephritis. No relationship was found between severity of lesions and presence of leptospires in the kidneys. The PCR results on the urine and blood were consistent with matching WS stained kidneys. Out of 13 kidneys that were positive with silver staining, 7 matching blood and 10 matching urine samples were confirmed positive for leptospirosis with PCR. In

  14. Leptospira Exposure and Gardeners: A Case-Control Seroprevalence Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Guido-Arreola, Carlos Alberto

    2016-01-01

    Background Leptospira can be found in soil. However, it is unclear whether occupational exposure to soil may represent a risk for Leptospira infection in humans. Therefore, we sought to determine the association of Leptospira IgG seroprevalence with the occupation of gardener, and to determine the epidemiological characteristics of gardeners associated with Leptospira exposure. Methods We performed a case-control study in 168 gardeners and 168 age- and gender-matched control subjects without gardening occupation in Durango City, Mexico. The seroprevalence of anti-Leptospira IgG antibodies in cases and controls was determined using an enzyme immunoassay. Bivariate and multivariate analyses were used to assess the association of Leptospira exposure and the characteristics of the gardeners. Results Anti-Leptospira IgG antibodies were found in 10 (6%) of 168 gardeners and in 15 (8.9%) of 168 control subjects (odds ratio (OR): 0.64; 95% confidence interval (CI): 0.28 - 1.48; P = 0.40). Multivariate analysis showed that Leptospira seropositivity was positively associated with female gender (OR: 5.82; 95% CI: 1.11 - 30.46; P = 0.03), and negatively associated with eating while working (OR: 0.21; 95% CI: 0.05 - 0.87; P = 0.03). In addition, multivariate analysis showed that high anti-Leptospira levels were associated with consumption of boar meat (OR: 28.00; 95% CI: 1.20 - 648.80; P = 0.03). Conclusions This is the first case-control study of Leptospira exposure in gardeners. Results do not support an association of Leptospira exposure with the occupation of gardener. However, further studies to confirm the lack of this association are needed. The potential role of consumption of boar meat in Leptospira infection deserves further investigation. PMID:26668679

  15. 9 CFR 113.102 - Leptospira Icterohaemorrhagiae Bacterin.

    Science.gov (United States)

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.102 Leptospira Icterohaemorrhagiae Bacterin....

  16. PREVALÊNCIA DE ANTICORPOS ANTI-Leptospira spp. E ASPECTOS EPIDEMIOLÓGICOS DA INFECÇÃO EM BOVINOS DO ESTADO DE GOIÁS

    Directory of Open Access Journals (Sweden)

    Alberto Elias Marques

    2010-10-01

    Full Text Available This study aimed to determine the prevalence of antibodies against Leptospira spp. and their regional distribution, and evaluate the main risk factors associated to the disease in cattle in the State of Goias, Brazil. The study was carried out using 4571 samples taken from 715 properties of 213 municipalities in the state of Goias. The samples were analysed by the microagglutination test (MAT. 62.2% of the samples were positive for at least one of the 16 serovars tested, with major prevalence of co-agglutination (40.24%, followed by serovars wolffi (14.53%, hardjo (12.70 %, grippotyphosa (10.55% and shermani (6.55%. The prevalence of anti-Leptospira spp. antibodies was associated to the following factors: stratum of production, with a greater prevalence in stractumof beef cattle production; practice of artificial insemination; cattle breed; presence of sheep and goats; presence of capybaras; purchase of reproducers in exhibitions and from other properties; pasture rent at any time of year; presence of maternity paddock, and occurrence of abortions. It was concluded that leptospiral infection is endemic in Goias State.

  17. 77 FR 43827 - International Workshop on Alternative Methods for Leptospira

    Science.gov (United States)

    2012-07-26

    ... Alternatives to Animal Testing (EURL ECVAM), the Japanese Center for the Validation of Alternative Methods, the... HUMAN SERVICES International Workshop on Alternative Methods for Leptospira Vaccine Potency Testing... Workshop on Alternative Methods for Leptospira Vaccine Potency Testing: State of the Science and the Way...

  18. Monitoring Leptospira Strain Collections: The Need for Quality Control

    NARCIS (Netherlands)

    G.M. Cerqueira; A.J.A. McBride; A. Queiroz; L.S. Pinto; E.E. Silva; R.A. Hartskeerl; M.G. Reis; A.I. Ko; O.A. Dellagostin

    2010-01-01

    The purpose of this study was to perform a 16S sequence-based quality control of two Leptospira strain collections. 16S rRNA gene sequencing was used to verify two Leptospira reference collections provided by the World Health Organization and maintained at a reference laboratory for leptospirosis in

  19. Genome Sequence of the Saprophyte Leptospira Biflexa Provides Insights into the Evolution of Leptospira and the Pathogenesis of Leptospirosis

    Science.gov (United States)

    Leptospira biflexa is a free-living spirochete found broadly distributed in aquatic environments, and is the primary model for studying gene function in Leptospira spp. The L. biflexa genome has 3,590 protein-coding genes (excluding transposases) distributed across three circular replicons: two of w...

  20. Leptospiral agglutinins in captive and free ranging non-human primates in Sarawak, Malaysia

    Directory of Open Access Journals (Sweden)

    S. Thayaparan

    2014-06-01

    Full Text Available Aim: The proposed study was carried out to determine the extent of exposure to leptospirosis in non-human primates. Materials and Methods: Trapping of non-human primates was carried out opportunistically around the Bako National Park and the Matang Wildlife Center in the vicinity of human settlements and tourism areas of Sarawak. Blood samples were obtained from the saphenous vein to determine the presence of antibodies by the Microscopic Agglutination Test (MAT to 17 serovars of Leptospira commonly found in Malaysia. Results: This study reports the screening of twelve primates (eight captive and four free ranging for leptospirosis. Eight of the 12 monkeys (66.6%; 95% CI 34.9-90.1 reacted against one or two serovars of Leptospira (Lai and Leptospira Lepto175. The serovar Lai is considered pathogenic for different mammals, including humans. Leptospira Lepto 175 has been identified as an intermediate strain and further studies are being undertaken on this serovar. Conclusion: These results are important as primates may act as reservoirs of Leptospira spp. for humans, which may potentially affect tourism (economic loss, conservation efforts and public health.

  1. Cloning and Expression of Leptospira LipL32 Antigen as a Candidate for Rapid Diagnosis

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    Nooshin Sohrabi

    2013-09-01

    Full Text Available Background and Objective: Leptospirosis as an important emerging infectious zoonotic disease caused by spirochetes of the genus Leptospira. Given the low sensitivity and long duration of its culture, the diagnosis of leptospirosis is mainly based on serological methods. The microscopic agglutination test (MAT is considered as the reference method. Because of the complexity of the MAT, there is an urgent need for the development of new reliable and rapid screening tests for leptospirosis. Major leptospiral outer membrane proteins (OMPs, present only in pathologic strains, could be regarded as a good candidate for diagnostic studies. Here we report the cloning and expression of LipL32, as a prominent immunogenic protein, in a prokaryotic system. Materials and Methods: After the amplification of LipL32 gene, it was cloned into the pQE30 vector. The insertion of LipL32 gene into the vector was screened and confirmed with restriction analysis and sequencing. The recombinant plasmid was transformed into E. coli M15 strain, and the expressed protein was identified by SDS-PAGE and western blotting. This recombinant protein with 6× His-tagged sequence was purified using Ni-NTA affinity column chromatography. Results: The results revealed that the selected gene was successfully cloned in pQE30 vector and recombinant protein (rLipL32 of approximately ~32 kDa was produced, purified and confirmed by western blotting. Conclusion: This recombinant protein could be potentially used for the development of serodiagnosis tests for the diagnosis of leptospirosis in humans and animals.

  2. Detection of Leptospira spp. in semen and vaginal fluids of goats and sheep by polymerase chain reaction.

    Science.gov (United States)

    Lilenbaum, W; Varges, R; Brandão, F Z; Cortez, A; de Souza, S O; Brandão, P E; Richtzenhain, L J; Vasconcellos, S A

    2008-04-15

    Thirteen goat herds and seven sheep flocks in the state of Rio de Janeiro, Brazil were screened for leptospirosis. From the three herds and three flocks with greatest seroreactivity, 19 goats (16 females and three bucks) and 40 sheep (26 ewes and 14 rams) that were seropositive (specific anti-Leptospira titres > or =400, based on a microscopic agglutination test), were selected for more detailed studies. From those animals, samples of vaginal fluids or semen were collected for bacteriological and molecular assays. For both species of animals, the most prevalent reactions were to serovars Hardjo, Shermani, and Grippotyphosa. Although leptospires were detected by darkfield microscopy in three vaginal fluid samples (from two goats and one ewe), pure isolates were not obtained by bacteriological culture of vaginal fluids or semen. However, seven vaginal fluid samples (from four goats and three ewes) and six semen samples (all from rams) were positive on polymerase chain reaction (PCR). Based on these findings, in addition to analogous findings in cattle, we inferred that there is potential for venereal transmission of leptospirosis in small ruminants.

  3. Differentiation of pathogenic and saprophytic leptospira strains.

    Science.gov (United States)

    Bazovská, S; Kmety, E; Rak, J

    1984-09-01

    Comparative studies of 249 pathogenic and 80 saprophytic leptospira strains, including 2 strains of the illini type, using the 8-azaguanine test, growth at 13 degrees C and growth on trypticase soy broth revealed their good differentiating potency if the recommended conditions were carefully observed. The same results were obtained by a simple hemolytic test using sheep and rat blood cells, having the advantage of providing results within 24 h. This test is suggested to replace the 8-azaguanine and the growth test at 13 degrees C. In these investigations, the first European strain of the illini type was recognized.

  4. Leptospira species in floodwater during the 2011 floods in the Bangkok Metropolitan Region, Thailand.

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    Thaipadungpanit, Janjira; Wuthiekanun, Vanaporn; Chantratita, Narisara; Yimsamran, Surapon; Amornchai, Premjit; Boonsilp, Siriphan; Maneeboonyang, Wanchai; Tharnpoophasiam, Prapin; Saiprom, Natnaree; Mahakunkijcharoen, Yuvadee; Day, Nicholas P J; Singhasivanon, Pratap; Peacock, Sharon J; Limmathurotsakul, Direk

    2013-10-01

    Floodwater samples (N = 110) collected during the 2011 Bangkok floods were tested for Leptospira using culture and polymerase chain reaction (PCR); 65 samples were PCR-positive for putatively non-pathogenic Leptospira species, 1 sample contained a putatively pathogenic Leptospira, and 6 samples contained Leptospira clustering phylogenetically with the intermediate group. The low prevalence of pathogenic and intermediate Leptospira in floodwater was consistent with the low number of human leptospirosis cases reported to the Bureau of Epidemiology in Thailand. This study provides baseline information on environmental Leptospira in Bangkok together with a set of laboratory tests that could be readily deployed in the event of future flooding.

  5. Factor analysis of serogroups botanica and aurisina of Leptospira biflexa.

    Science.gov (United States)

    Cinco, M

    1977-11-01

    Factor analysis is performed on serovars of Botanica and Aurisina serogroup of Leptospira biflexa. The results show the arrangement of main factors serovar and serogroup specific, as well as the antigens common with serovars of heterologous serogroups.

  6. Seroprevalence of Brucella abortus and Leptospira hardjo in cattle

    OpenAIRE

    2015-01-01

    Aim: The aim was to assess the seroprevalence of B. abortus and Leptospira hardjo in the cattle population of Bihar, this work was carried out. Materials and Methods: Randomly selected 450 cattle from nine districts of Bihar were serologically screened for antibodies against L. hardjo and B. abortus. DAS-ELISA for leptospira and AB-ELISA for brucella were carried out. Based on the results prevalence in each district and the state are reported herewith. Results and Discussion: In this study, i...

  7. Field rats form a major infection source of leptospirosis in and around Madurai, India.

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    Priya, C G; Hoogendijk, K T; Berg, Mvd; Rathinam, S R; Ahmed, A; Muthukkaruppan, V R; Hartskeerl, R A

    2007-01-01

    To determine the seroprevalence of leptospires and to isolate Leptospira spp. from field rats and bandicoots in and around Madurai. Thirteen rats and five bandicoots were trapped alive from fields in and around Madurai. Blood samples were tested for anti-leptospiral antibodies by microscopic agglutination test while the urine and kidney samples were used for isolation of leptospires. The isolated leptospires were tested for pathogenic status (13 degrees C test and PCR) followed by serological and genetic characterization. Serology revealed the presence of anti-leptospiral antibodies in 58% (7/12) of field rats and leptospires were isolated from two urine and six kidney samples. The bandicoots were negative in both serology and culture. Analysis of the isolates from field rats revealed that all the isolates were pathogenic except for one, which was further confirmed by serological and genetic characterization. Six of the seven pathogenic isolates were identified as L. interrogans serogroup Autumnalis serovar Akiyami A and one as L. borgpetersenii serogroup Javanica serovar Veldrat Batavia 46. Serology and isolation reveals that field rats are major natural carriers and shedders of leptospires in and around Madurai.

  8. Field rats form a major infection source of leptospirosis in and around Madurai, India

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    Priya C

    2007-01-01

    Full Text Available Aims: To determine the seroprevalence of leptospires and to isolate Leptospira spp. from field rats and bandicoots in and around Madurai. Materials and Methods: Thirteen rats and five bandicoots were trapped alive from fields in and around Madurai. Blood samples were tested for anti-leptospiral antibodies by microscopic agglutination test while the urine and kidney samples were used for isolation of leptospires. The isolated leptospires were tested for pathogenic status (13°C test and PCR followed by serological and genetic characterization. Results: Serology revealed the presence of anti-leptospiral antibodies in 58% (7/12 of field rats and leptospires were isolated from two urine and six kidney samples. The bandicoots were negative in both serology and culture. Analysis of the isolates from field rats revealed that all the isolates were pathogenic except for one, which was further confirmed by serological and genetic characterization. Six of the seven pathogenic isolates were identified as L. interrogans serogroup Autumnalis serovar Akiyami A and one as L. borgpetersenii serogroup Javanica serovar Veldrat Batavia 46. Conclusions: Serology and isolation reveals that field rats are major natural carriers and shedders of leptospires in and around Madurai.

  9. Diversity of Leptospira spp. in Rats and Environment from Urban Areas of Sarawak, Malaysia

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    Chai Fung Pui

    2017-01-01

    Full Text Available Various prevalence studies on Leptospira in animals and humans, as well as environmental samples, had been conducted worldwide, including Malaysia. However, limited studies have been documented on the presence of pathogenic, intermediate, and saprophytic Leptospira in selected animals and environments. This study was therefore conducted to detect Leptospira spp. in rats, soil, and water from urban areas of Sarawak using the polymerase chain reaction (PCR method. A total of 107 rats, 292 soil samples, and 324 water samples were collected from April 2014 to February 2015. Pathogenic Leptospira was present in 5.6% (6/107 of rats, 11.6% (34/292 of soil samples, and 1.9% (6/324 of water samples. Intermediate Leptospira was present in 2.7% (8/292 of soil samples and 1.9% (6/324 of water samples. Saprophytic Leptospira was present in 10.3% (11/107 of rats, 1.4% (4/292 of soil samples, and 0.3% (1/324 of water samples. From this study, 76 Leptospira spp. were isolated. Based on DNA sequencing, the dominant Leptospira spp. circulating in urban areas of Sarawak are pathogenic Leptospira noguchii, intermediate Leptospira wolffii serovar Khorat, and saprophytic Leptospira meyeri, respectively. Overall, this study provided important surveillance data on the prevalence of Leptospira spp. from rats and the environment, with dominant local serovars in urban areas of Sarawak.

  10. Diversity of Leptospira spp. in Rats and Environment from Urban Areas of Sarawak, Malaysia.

    Science.gov (United States)

    Pui, Chai Fung; Bilung, Lesley Maurice; Apun, Kasing; Su'ut, Lela

    2017-01-01

    Various prevalence studies on Leptospira in animals and humans, as well as environmental samples, had been conducted worldwide, including Malaysia. However, limited studies have been documented on the presence of pathogenic, intermediate, and saprophytic Leptospira in selected animals and environments. This study was therefore conducted to detect Leptospira spp. in rats, soil, and water from urban areas of Sarawak using the polymerase chain reaction (PCR) method. A total of 107 rats, 292 soil samples, and 324 water samples were collected from April 2014 to February 2015. Pathogenic Leptospira was present in 5.6% (6/107) of rats, 11.6% (34/292) of soil samples, and 1.9% (6/324) of water samples. Intermediate Leptospira was present in 2.7% (8/292) of soil samples and 1.9% (6/324) of water samples. Saprophytic Leptospira was present in 10.3% (11/107) of rats, 1.4% (4/292) of soil samples, and 0.3% (1/324) of water samples. From this study, 76 Leptospira spp. were isolated. Based on DNA sequencing, the dominant Leptospira spp. circulating in urban areas of Sarawak are pathogenic Leptospira noguchii, intermediate Leptospira wolffii serovar Khorat, and saprophytic Leptospira meyeri, respectively. Overall, this study provided important surveillance data on the prevalence of Leptospira spp. from rats and the environment, with dominant local serovars in urban areas of Sarawak.

  11. Evaluation of truncated LipL32 expressed by Escherichia coli and Pichia pastoris for serodiagnosis of Leptospira infection in rodents.

    Science.gov (United States)

    Shiokawa, Kanae; Gamage, Chandika D; Koizumi, Nobuo; Sakoda, Yoshihiro; Shimizu, Kenta; Tsuda, Yoshimi; Yoshimatsu, Kumiko; Arikawa, Jiro

    2016-02-01

    The applicability of the recombinant LipL32 for serodiagnosis of leptospiral infection in field rodents was assessed in this study. An immunodominant region of LipL32 was determined by monoclonal antibodies, and then, truncated LipL32 (tLipL32) was designed to contain the region (87-188th amino acid). The tLipL32 was compared between two recombinant expression hosts Escherichia coli and Pichia pastoris in ELISA. With field rat sera, tLipL32 expressed by P. pastoris (tLipL32p) had high antigenicity without background reactions, while tLipL32 expressed by E. coli (tLipL32e) showed high background reactions, which were reduced by pre-adsorption of sera with E. coli. To evaluate tLipL32-ELISA, field rat sera were tentatively divided into a Leptospira infection positive (12 sera) and a negative group (12 sera) based on the results from flaB gene PCR of kidney samples and WB with whole Leptospira cell. Consequently, the sensitivity of tLipL32p-ELISA for field rat sera was 83% . A similar result was obtained from tLipL32e-ELISA with adsorbed sera, (92%). However, sensitivity of tLipL32e-ELISA using sera without an adsorption treatment was 50%. Regardless of the expression host, tLipL32-ELISA had 100% specificity and sensitivity in experimentally infected laboratory rats. These results suggest that recombinant LipL32 expressed by P. pastoris is more applicable for serodiagnosis in field rats due to a lack of background reaction.

  12. [35 leptospira isolated from the vitreous body of 32 horses with recurrent uveitis (ERU)].

    Science.gov (United States)

    Brem, S; Gerhards, H; Wollanke, B; Meyer, P; Kopp, H

    1999-01-01

    130 vitreous samples, systematically collected in 1998 from 117 horses during vitrectomy, were cultured for the presence of leptospires. All horses suffered from equine recurrent uveitis (ERU), also known as periodic ophthalmia or moon blindness, and were treated surgically to combat painful attacks, and to preserve vision. In 35 out of 130 vitreous samples (35/130 = 26.9%), leptospires could be isolated. These isolates belong to the grippotyphosa serogroup (n = 31) and to the australis serogroup (n = 4). So, for the first time, leptospires were recovered from eyes in vivo in a large number of horses with ERU. Vitreous samples and one serum sample from each horse were also tested for leptospiral antibodies using the microscopic agglutination test (MAT). In 92 vitreous samples (92/130 = 70.7%) and 96 serum samples (96/117 = 82.0%) leptospiral antibodies were detected at a dilution of > 1:100. The presence of intact leptospires and specific antibodies in eyes affected with ERU demonstrates a local antibody production to leptospiral antigen. These results indicate an important etiological role of leptospires in equine recurrent uveitis.

  13. Overlooked Risk for Chronic Kidney Disease after Leptospiral Infection: A Population-Based Survey and Epidemiological Cohort Evidence.

    Science.gov (United States)

    Yang, Huang-Yu; Hung, Cheng-Chieh; Liu, Su-Hsun; Guo, Yi-Gen; Chen, Yung-Chang; Ko, Yi-Ching; Huang, Chiung-Tseng; Chou, Li-Fang; Tian, Ya-Chung; Chang, Ming-Yang; Hsu, Hsiang-Hao; Lin, Ming-Yen; Hwang, Shang-Jyh; Yang, Chih-Wei

    2015-01-01

    Leptospirosis is the most widespread zoonosis. Chronic human infection and asymptomatic colonization have been reported. However, renal involvement in those with leptospira chronic exposure remains undetermined. In 2007, a multistage sampling survey for chronic kidney disease (CKD) was conducted in a southern county of Taiwan, an area with a high prevalence of dialysis. Additionally, an independent cohort of 88 participants from a leptospira-endemic town was followed for two years after a flooding in 2009. Risks of CKD, stages of CKD, associated risk factors as well as kidney injury markers were compared among adults with anti-leptospira antibody as defined by titers of microscopic agglutination test (MAT). Of 3045 survey participants, the individuals with previous leptospira exposure disclosed a lower level of eGFR (98.3 ± 0.4 vs 100.8 ± 0.6 ml/min per 1.73 m2, P CKDu) such as Mesoamerican Nephropathy.

  14. Aborto eqüino por Leptospira sp. Leptospira sp. as a cause of equine abortion

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    Caroline Argenta Pescador

    2004-02-01

    Full Text Available Descreve-se um caso de aborto eqüino por Leptospira sp. em um feto de 6 meses proveniente de um estabelecimento localizado próximo a Porto Alegre/RS. As lesões macroscópicas se caracterizaram por icterícia e hemorragias distribuídas difusamente sobre a pele, mucosa oral, tecido subcutâneo, pulmão, coração e sistema gastrintestinal. O fígado estava aumentado de tamanho, friável e de coloração amarelada. Os rins apresentavam hemorragias petequiais na superfície capsular e na superfície de corte observaram-se palidez da região cortical e medular. Cortes de rim e sistema nervoso central, corados por Warthin-Starry, revelaram a presença de espiroquetas nos túbulos, glomérulos e substância branca do encéfalo. Cultivo aeróbio de amostras de fígado e pulmão não revelaram crescimento bacteriano significativo. O teste de imunofluorescência direta para Leptospira sp. foi positivo e a sorologia fetal resultou numa titulação de 80 para o sorovar copenhageni e 40 para os sorovares icterohaemorragiae e pomona.This report describes an abortion on 6-month-old equine aborted fetus that has been caused by Leptospira sp. Main lesions included jaundice and hemorrhages diffusely scattered throughout the skin, oral mucosa, subcutaneous tissues, lungs, heart and gastrointestinal system. The liver was enlarged, pliable and yellow colored. The cortical and medullar of the kidneys were pale and petechial hemorrhages were present on the capsular surface. Warthin-Starry stained slices of the kidneys and central nervous system revealed the presence of spirochaetes within the tubules, glomeruli and white matter of the encephalo. Aerobic cultivation from samples of the liver and lungs were negative. The direct immunofluorescence test for Leptospira sp. was positive and the fetus’s serological test resulted titers of 80 against sorotype copenhageni and 40 against the sorotypes icterohaemorragiae and pomona.

  15. Contribution of Leptospira, Neospora caninum and bovine viral diarrhea virus to fetal loss of beef cattle in New Zealand.

    Science.gov (United States)

    Sanhueza, J M; Heuer, C; West, D

    2013-10-01

    The profitability of beef breeding farms in New Zealand depends principally on optimal reproductive performance. The aim of this study was to estimate the impact of four major pathogens, bovine viral diarrhea virus (BVDV), Neospora caninum (N. caninum), Leptospira borgpetersenii serovar Hardjo (Hardjo), and Leptospira interrogans serovar Pomona (Pomona), on rates of fetal loss in commercial beef breeding herds. Farms reporting fetal loss were recruited, and a blood sample from aborting cows (cases) was collected. Controls were normally calving cows from the same farm. At least four controls were selected from each farm contributing cases. Samples were tested using ELISA for detection of antibodies against BVDV and N. caninum, and microscopic agglutination test (MAT) for detection of antibody against Hardjo and Pomona. A selection of titer cut-offs was conducted to evaluate the relationship between fetal loss and seropositivity to each pathogen using conditional logistic regression. The cut-off titer with the strongest association with fetal loss was included in the multivariate model. A significant increased risk of fetal loss was found for animals seropositive to N. caninum (odds ratio (OR)=3.36; 95% confidence interval (95% CI)=1.27-8.89), Hardjo (OR=1.84; 95% CI=1.01-3.33), and Pomona in non-vaccinated cows (OR=14.91, 95% CI=1.73-128.84) at the ELISA titer ≥ 30, and MAT titers of ≥ 1:384 and ≥ 1:768 for a positive sample, respectively. A marginally non-significant increased risk of fetal loss was found for animals exposed to BVDV (OR=2.01; 95% CI=0.99-4.11) at the ELISA titer of ≤ 1. Vaccination did not affect ORs for Hardjo or BVDV and no herd vaccinated against N. caninum. Approximately 14.0% of all fetal loss in the beef breeding cattle population in New Zealand may be attributable to BVDV (3.5%), N. caninum (3.0%), Hardjo (4.7%), and Pomona (3.6%). Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Leptospira seroprevalence and associations between seropositivity, clinical disease and host factors in horses

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    Engvall E Olsson

    2009-03-01

    Full Text Available Abstract Background A cross-sectional study was carried out to determine the seroprevalence of different serovars of Leptospira spp. and their association with clinical disease and host factors in Swedish horses. Methods Sera from 2017 horses brought to equine clinics during 1997–98 were investigated. The sera were examined by microscopic agglutination test for the presence of antibodies against the following L. interrogans serovars: Bratislava strain Jez, Icterohaemorrhagiae strain Kantorowicz and Pomona strain Pomona and also L. kirschneri sv Grippotyphosa strain Duyster and L. borgpetersenii sv Sejroe strain M 84. Host factors, disease factors, season, pasture access and outdoor confinement variables were analysed with respect to seropositivity to sv Bratislava and Icterohaemorrhagiae. Multivariable logistic regression was used to model seropositivity to sv Bratislava and Icterohaemorrhagiae (seroprevalence > 8%. Results The seroprevalence, at a cut-off 1:100, were for sv Bratislava (16.6%, Icterohaemorrhagiae (8.3%, Sejroe (1.2%, Pomona (0.5% and Grippotyphosa (0.4%. In the multivariable analysis, it was demonstrated that seroprevalence increased with age for sv Bratislava and Icterohaemorrhagiae. For sv Bratislava the seasons April – June and October – December and for sv Icterohaemorrhagiae October – December had higher seroprevalences than other seasons. Horses not used for racing had higher levels of seropositivity to sv Bratislava. Furthermore, horses with respiratory problems as well as horses with fatigue had higher levels of seropositivity to sv Bratislava. Ponies and coldbloods, and horses with access to pasture, had lower seroprevalence for sv Icterohaemorrhagiae. Healthy horses had lower seroprevalence for sv Icterohaemorrhagiae, than non-healthy horses. Conclusion There was no significant association between clinical signs and disease and positive titres to sv Bratislava (except for the association between respiratory

  17. Seroepidemiology of Leptospira Exposure in General Population in Rural Durango, Mexico

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    Cosme Alvarado-Esquivel

    2015-01-01

    Full Text Available The magnitude of Leptospira exposure in rural Mexico is largely unknown. We sought to determine the seroprevalence of Leptospira IgG antibodies in adults in rural Durango, Mexico, and to determine the sociodemographic, behavioral, and housing characteristics of the subjects associated with Leptospira seropositivity. We performed a cross-sectional study in 282 adults living in rural Durango, Mexico. Sera from participants were analyzed for Leptospira IgG antibodies using a commercially available enzyme immunoassay. Seroprevalence association with the characteristics of the subjects was analyzed by bivariate and multivariate analyses. Of the 282 rural subjects (42.91 ± 17.53 years old studied, 44 (15.6% had anti-Leptospira IgG antibodies. Seropositivity to Leptospira was not associated with gender, educational level, employment, socioeconomic status, contact with animals or soil, or type of floors at home. In contrast, multivariate analysis showed that Leptospira exposure was associated with national trips (OR = 2.09; 95% CI: 1.05–4.16; P=0.03 and poor education of the head of the family (OR = 2.96; 95% CI: 1.51–5.78; P=0.001. We demonstrated serological evidence of Leptospira exposure in adults in rural northern Mexico. The contributing factors associated with Leptospira exposure found in the present study may be useful for optimal planning of preventive measures against Leptospira infection.

  18. Study on cellular location of protein LA_1100 in Leptospira%钩端螺旋体LA_1100蛋白膜定位研究

    Institute of Scientific and Technical Information of China (English)

    赵蔚; 陈春燕; 杨宏亮; 胡宝瑜; 郭晓奎; 秦金红

    2012-01-01

    Objective To investigate the cellular location and conservation of LA_1100 in Leptospira, Methods The characteristics and the three-dimensional structure of the protein were analyzed by several bioinformation softwares. Triton X-114 fractionation and Fluorescence-activated cell sorter were used to verify the location of LA_1100. Western blot and PCR were performed to study the conservation of LA_1100 among 13 Leptospira strains prevalent in China. Results LA_1100 protein had shown a-helices and p-fold with its secondary structure. The built structure of the protein LA_1100 was an assembly of a trimeric single pore channel. By means of Triton X-114 fractionation and Fluorescence-activated cell sorter, it showed that LA _1100 was an outer membrane protein. Among the 13 Leptospira strains prevalent in China, there were 12 with LA_1100 genes or showing positive results by both Western blot and PCR. Conclusion LA_1100 is the surface-exposed pore-forming outer membrane protein of Leptospira and conserved among Leptospira strains prevalent in China. These findings indicate that LA_ 1100 may be associated with adhesion and virulence of L. interrogans.%目的 研究LA_1100蛋白在钩端螺旋体中的膜定位并分析其在中国流行血清群中的保守性.方法 利用生物信息学软件对LA_1100的二级及三级结构进行分析,以Triton X-114抽提分离钩体细胞的各个组分,Westernblot及FACS方法验证LA_1100在钩端螺旋体中的膜定位.Western Blot和PCR在蛋白水平及核酸水平检测了其在13个中国流行血清群代表株中的保守性.结果 LA_1100的二级结构显示具有α-螺旋及β-折叠结构,进一步分析表明,此蛋白具有跨膜区.LA_1100单体结构具有典型的TolC结构域,三级结构模拟显示三聚体可形成孔状结构.膜定位显示,该蛋白定位于外膜.该基因的保守性分析结果表明,在中国13个流行代表株中有12株均检出该基因或该蛋白的特征性条带.结论 LA_1100

  19. What Makes a Bacterial Species Pathogenic?:Comparative Genomic Analysis of the Genus Leptospira.

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    Derrick E Fouts

    2016-02-01

    Full Text Available Leptospirosis, caused by spirochetes of the genus Leptospira, is a globally widespread, neglected and emerging zoonotic disease. While whole genome analysis of individual pathogenic, intermediately pathogenic and saprophytic Leptospira species has been reported, comprehensive cross-species genomic comparison of all known species of infectious and non-infectious Leptospira, with the goal of identifying genes related to pathogenesis and mammalian host adaptation, remains a key gap in the field. Infectious Leptospira, comprised of pathogenic and intermediately pathogenic Leptospira, evolutionarily diverged from non-infectious, saprophytic Leptospira, as demonstrated by the following computational biology analyses: 1 the definitive taxonomy and evolutionary relatedness among all known Leptospira species; 2 genomically-predicted metabolic reconstructions that indicate novel adaptation of infectious Leptospira to mammals, including sialic acid biosynthesis, pathogen-specific porphyrin metabolism and the first-time demonstration of cobalamin (B12 autotrophy as a bacterial virulence factor; 3 CRISPR/Cas systems demonstrated only to be present in pathogenic Leptospira, suggesting a potential mechanism for this clade's refractoriness to gene targeting; 4 finding Leptospira pathogen-specific specialized protein secretion systems; 5 novel virulence-related genes/gene families such as the Virulence Modifying (VM (PF07598 paralogs proteins and pathogen-specific adhesins; 6 discovery of novel, pathogen-specific protein modification and secretion mechanisms including unique lipoprotein signal peptide motifs, Sec-independent twin arginine protein secretion motifs, and the absence of certain canonical signal recognition particle proteins from all Leptospira; and 7 and demonstration of infectious Leptospira-specific signal-responsive gene expression, motility and chemotaxis systems. By identifying large scale changes in infectious (pathogenic and intermediately

  20. DETERMINASI SEROVAR BAKTERI LEPTOSPIRA PADA RESERVOIR DI KABUPATEN BANYUMAS

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    Tri Ramadhani

    2016-05-01

    Full Text Available Leptospirosis is an infectious disease caused by pathogenic Leptospira. Leptospirosis transmitted to human through direct contact with body fluids of infected animals or indirectly through contaminated puddles . The prevalence of leptospirosis in Banyumas tends to increase for 3 years. The purpose of this study was to determine the leptospira serovar in reservoir to prove of a current infection. Surveys was conducted using single live traps for three consecutive days, determination of leptospira serovar was conducted using Microscopic Aglutination Test (MAT. Data analysis was performed by univariate and presented in tables and graphs. The results showed that the trapped animals consisted of Rattus tanezumi (70.6% and Suncus murinus (29.4% with 6.5% succsess trap. Rattus tanezumi were dominantly caught inside the house (51% than outside the house (49%. Female rats were dominantly caught (66.7% than male rats (33.3%. Suncus murinus and Rattus tanezumi shown a titer of 1/100 to be infected with L.icterohaemorrhagiae , L.javanica and L.cynopteri which are pathogenic Leptospira in humans. Efforts are needed to improve community participation in preventing tranmission of leptospirosis by avoiding contact with contaminated water and soil. For people who are risk of exposure to infected animal should wear protective clothes or footwear.

  1. InvA-PCR快速检测鼠肾标本中钩端螺旋体%InvA-PCR for rapid detection of leptospira in rat kidney specimens

    Institute of Scientific and Technical Information of China (English)

    鲍庆汉; 姜理平

    2012-01-01

    Objective:To validate an InvA - PCR method for rapid detection of leptospira in rat kidney specimens. Methods:The InvA - PCR method was used to detect leptospira in 106 rat kidney specimens collected from Chun'an county in2009. At the same time, bacterial culture was applied to the specimens, and microscopic agglutination test (MAT) was employed for serological identification when positive culture was gotten. Results:Out of 106 rat kidney specimens, 9 cases (8. 5% ) were leptospiral invA gene positive by the InvA - PCR, while 3 (2. 8% ) strains of Leptospira were isolated. All of these 3 isolates belonged to the serogroup of icterohaemorrhagiae. The 3 specimens with positive culture were all positive by the InvA - PCR assay. Conclusion: InvA - PCR method has the advantages of convenient operation, short time consumption, strong specificity and high sensitivity. It can be used as a reliable rapid diagnostic method for pathogenic Leptospira in leptospirosis epidemiology investigation and leptospiro-sis quick screening in clinic.%目的:探讨InvA-PCR方法快速检测钩端螺旋体的应用价值.方法:对2009年淳安县106只鼠肾标本直接提取其DNA用invA-PCR法进行检测,同时对106只鼠肾标本进行分离培养和显微镜凝集试验(MAT)血清学鉴定.结果:106只鼠肾标本经InvA-PCR法检测,9份标本钩端螺旋体invA基因呈阳性,阳性率为8.5%.106只鼠肾标本分离培养,分离到3株钩端螺旋体菌株,均为黄疸出血群,阳性率为2.8%.3份培养阳性标本InvA-PCR均阳性.结论:InvA-PCR方法操作方便、耗时短、特异性强、灵敏度高,可作为致病性钩端螺旋体可靠的快速诊断方法,可用于钩体病的流行病学调查和钩体病临床标本快速初筛.

  2. 问号钩体粘附侵袭相关基因特征分析%Characteristic Analysis of Adhesion and Invasion Genes in Leptospira interrogans

    Institute of Scientific and Technical Information of China (English)

    杨宏亮; 李文俊; 姜叙诚; 郭晓奎

    2004-01-01

    使用NCBI,Swissprot/TrEMBL,ProDom,Pfam,Tmpred,SignalP,ClustW等网络资源和软件,根据问号钩体黄疸出血型赖株粘附侵袭相关基因诠释结果,对mce,invA,mviN和atsE四个粘附侵袭相关基因编码蛋白的结构域、跨膜区域和信号肽等进行了详细分析,并使用Bioedit,Mega2软件进行氨基酸多重序列比较并绘制系统发生树.结果显示,mce和mviN为穿膜蛋白,invA和atsE为菌体内蛋白质;许多对哺乳动物和对植物致病的微生物具有mce,invA,mviN和atsE四个粘附侵袭相关基因,其表达的蛋白质在感染宿主过程中起重要作用,钩体的粘附侵袭相关蛋白与它们在一级结构上有较高相似性.据生物信息学结果推测,问号钩体黄疸出血型赖株粘附侵袭相关基因和钩体致病性间有密切关系,其编码蛋白在致病过程中可能起重要作用.

  3. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts.

    Science.gov (United States)

    Mgode, Georgies F; Machang'u, Robert S; Mhamphi, Ginethon G; Katakweba, Abdul; Mulungu, Loth S; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A; Belmain, Steven R

    2015-12-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries.

  4. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts.

    Directory of Open Access Journals (Sweden)

    Georgies F Mgode

    2015-12-01

    Full Text Available The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT, and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents; Kenya (rodents and shrews; Mwogolo (rodents; Lora (rodents; Qunjian (rodent; serogroup Grippotyphosa (cattle; and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries.

  5. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts

    Science.gov (United States)

    Mgode, Georgies F.; Machang’u, Robert S.; Mhamphi, Ginethon G.; Katakweba, Abdul; Mulungu, Loth S.; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A.; Belmain, Steven R.

    2015-01-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries. PMID:26624890

  6. Anti-leptospiral agglutinins in marmosets (Saguinus oedipus and Saguinus leucopus from illegal trade

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    Viviana Gonzalez-Astudillo

    2015-09-01

    Full Text Available Objective. Determine the infection status with pathogenic Leptospira of one Saguinus oedipus and nine Saguinus leucopus at the Cali Zoo that had been confiscated in Colombia from illegal trade. Materials and methods. A full physical examination, blood work, urinalysis were conducted in all individuals during the reception health check-up, in addition to running the microagglutination test with a pool of 19 serovars, with a starting dilution of 1:50. Results. A high positive titer (≥1:3200 to Leptospira alexanderi serovar manhao in an asymptomatic S. oedipus was detected. All S. leucopus tested negative or less than 1:50. Conclusions. Captive locations have been documented to artificially enhance opportunities to come into contact with contaminated bodily fluids from peridomestic rodents. However, infectious diseases acquired during the illegal transport of wildlife to major metropolitan centers are rarely considered a wildlife conservation or public health threat. Infection with zoonotic pathogens should also be considered an additional threat to endangered wild primates involved in illegal trade, which could hamper reintroduction efforts or other population management procedures for primate species with restricted and fragmented distributions.

  7. PREVALENSI TIKUS TERINFEKSI Leptospira interogans DI KOTA SEMARANG, JAWA TENGAH

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    Ristiyanto Ristiyanto

    2015-10-01

    Full Text Available AbstrakLeptospirosis merupakan zoonosis.Penyakit ini sering dijumpai di daerah perkotaan terutama yang sering dilanda banjir.Manusia terinfeksi bakteri Leptospira melalui air atau tanah yang terkontaminasi dengan urin atau cairan tubuh inang reservoir.Tikus adalah inang reservoir leptospirosis.Penelitian ini bertujuan untuk mengetahui populasi tikus yang terinfeksi Leptospira dan interaksi antara pasien suspek leptospira dengan tikus­Kota­Semarang,­Jawa­Tengah.­Selain­itu­dilakukan­pula­identifikasi­serovar­Leptospira­padatikus­diKota Semarang, Jawa Tengah. Jenis penelitian adalah potonglintang (cross sectional.Dilakukan pengamatan di rumah dan lingkungan tempat tinggal 68 kasus leptospirosis. Penangkapan tikus menggunakan perangkap hidup sejumlah 100 buah.Pemasang perangkap di dalam dan di luar rumah selama 3 hari.  Tikus yang tertangkap­diidentifikasi­dan­diambil­serum­darahnya­untuk­mengetahui­serovar­Leptospira­dengan­uji­MAT.Seluruh 68 kasus leptospirosis dari Rumah Sakit di Kota Semarang memiliki riwayat interaksi dengan tikus. Prevalensi tikus terinfeksi bakteri leptospira  untuk tikus got (R. norvegicus 33,43% dan tikus rumah (R. tanezumi­13,69%.­Serovar­Leptospira­yang­diidentifikasi­pada­tikus­got­(R.­norvegicus­adalah­Djasiman(40,55% dari 27 ekor, Icterohaemorhagie (22,22% , Autumnalis (20,35 dan Bataviae (16,68%. Sementara pada­tikus­rumah­(R.­tanezumi­dapat­diidentifikasikan­serovar­Autumnalis­(66,67%­dari­3­ekor­dan­Bataviae(33,33%. Hal ini menunjukkan bahwa tikus merupakan reservoir penting dari leptospirosis. Penelitian ini menunjukkan bahwa tikus got (R. norvegicus dan tikus rumah (R. tanezumi memiliki potensi besar untuk menjadi vektor penularan bakteri Leptospira di Kota Semarang.Kata Kunci : Leptospirosis, Tikus, Faktor Risiko, SemarangAbstractLeptospirosis­is­a­zoonosis.­The­disease­is­often­found­in­urban­areas,­especially­the­frequent­flooding.

  8. Antileptospiral activity of xanthones from Garcinia mangostana and synergy of gamma-mangostin with penicillin G.

    Science.gov (United States)

    Seesom, Weeranuch; Jaratrungtawee, Amornmart; Suksamrarn, Sunit; Mekseepralard, Chantana; Ratananukul, Piniti; Sukhumsirichart, Wasana

    2013-07-19

    Leptospirosis, one of the most widespread zoonotic infectious diseases worldwide, is caused by spirochetes bacteria of the genus Leptospira. The present study examined inhibitory activity of purified xanthones and crude extracts from Garcinia mangostana against both non-pathogenic and pathogenic leptospira. Synergy between γ-mangostin and penicillin G against leptospires was also determined. Minimal inhibitory concentrations (MIC) of crude extracts and purified xanthones from G. mangostana and penicillin G for a non-pathogenic (L. biflexa serovar Patoc) and pathogenic (L. interrogans serovar Bataviae, Autumnalis, Javanica and Saigon) leptospires were determined by using broth microdilution method and alamar blue. The synergy was evaluated by calculating the fractional inhibitory concentration (FIC) index. The results of broth microdilution test demonstrated that the crude extract and purified xanthones from mangosteen possessed antileptospiral activities. The crude extracts were active against all five serovars of test leptospira with MICs ranging from 200 to ≥ 800 μg/ml. Among the crude extracts and purified xanthones, garcinone C was the most active compound against both of pathogenic (MIC =100 μg/ml) and non-pathogenic leptospira (MIC = 200 μg/ml). However, these MIC values were higher than those of traditional antibiotics. Combinations of γ-mangostin with penicillin G generated synergistic effect against L. interrogans serovars Bataviae, Autumnalis and Javanica (FIC = 0.52, 0.50, and 0.04, respectively) and no interaction against L. biflexa serovar Patoc (FIC =0.75). However, antagonistic activity (FIC = 4.03) was observed in L. interrogans serovar Saigon. Crude extracts and purified xanthones from fruit pericarp of G. mangostana with significant antibacterial activity may be used to control leptospirosis. The combination of xanthone with antibiotic enhances the antileptospiral efficacy.

  9. Study on Seroprevalence and Leptospiral Antibody Distribution among High-risk Planters in Malaysia.

    Science.gov (United States)

    Ridzuan, J Mohd; Aziah, B D; Zahiruddin, W M

    2016-06-01

    To determine the leptospirosis seroprevalence and to identify the predominant infecting serovars among oil palm plantation workers. The cross-sectional study involved 350 asymptomatic oil palm plantation workers in Melaka and Johor. A serological test using the microscopic agglutination test was conducted in the Institute of Medical Research with a cut-off titre for seropositivity of ≥1:100. The overall seroprevalence of leptospiral antibodies was 28.6%. The job category with the highest seroprevalence was the fruit collector with 59.2%. The predominant serovar identified was serovar Sarawak (Lepto 175) (62%). A high seroprevalence of leptospiral antibodies was detected among oil palm plantation workers and specifically among fruit collectors. The predominant infecting serovar among the workers was serovar Sarawak (Lepto 175). The findings suggest that more studies are needed to determine the reasons for the high seroprevalence and the transmission and pathogenicity of the local serovar Sarawak (Lepto 175).

  10. Maximizing the chances of detecting pathogenic leptospires in mammals: the evaluation of field samples and a multi-sample-per-mammal, multi-test approach.

    Science.gov (United States)

    Tulsiani, S M; Graham, G C; Dohnt, M F; Burns, M-A; Craig, S B

    2011-03-01

    Identification of wild animals that harbour the causative leptospires, and the identification of the most important of these 'wild reservoirs' (in terms of threat to human health), are key factors in the epidemiology of human leptospirosis. In an epidemiological investigation in the Australian state of Queensland, in 2007-2008, samples were collected from fruit bats (Pteropus conspicillatus) and rodents (to investigate the potential role of fruit bats in the maintenance and transmission of leptospires to ground-dwelling rodents) and checked for pathogenic leptospires. The results of these studies have now been carefully analysed in attempts to see which method of detection and type of test sample were best. The effects of pentobarbitone sodium used to euthanize wild mammals before collection of necropsy samples, on the survival and detection of leptospires in vitro, were also explored. In the earlier field investigation, serum, renal tissue and urine were collected from wild mammals, for the detection of pathogenic leptospires by culture, the microscopic agglutination test (MAT), real-time PCR and silver impregnation of smears. Although 27.6% of the rodents investigated were found leptospire-positive, culture only yielded four isolates, probably because many cultures were contaminated. The main aims of the present study were to quantify the performance of the individual diagnostic tests and examine the reasons behind the high incidence of culture contamination. The results of sensitivity and specificity analyses for the different diagnostic tests indicated that isolation by culture (the definitive diagnostic test for leptospiral shedding) had perfect (100%) sensitivity when compared with the results of the PCR but a low specificity (40%). The MAT performed poorly, with a sensitivity of 50% when compared against the results of culture. The prevalence of leptospiral carriage revealed by the PCR-based investigation of kidney and urine samples (59.2%) was higher than

  11. High Seroprevalence of Leptospira Exposure in Meat Workers in Northern Mexico: A Case-Control Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Hernandez-Tinoco, Jesus; Sanchez-Anguiano, Luis Francisco; Ramos-Nevarez, Agar; Cerrillo-Soto, Sandra Margarita; Saenz-Soto, Leandro; Martinez-Ramirez, Lucio

    2016-01-01

    Background The seroepidemiology of Leptospira infection in workers occupationally exposed to raw meat has been poorly studied. This work aimed to determine the association between Leptospira exposure and the occupation of meat worker, and to determine the seroprevalence association with socio-demographic, work, clinical and behavioral characteristics of the meat workers studied. Methods We performed a case-control study in 124 meat workers and 124 age- and gender-matched control subjects in Durango City, Mexico. Sera of cases and controls were analyzed for anti-Leptospira IgG antibodies using a commercially available enzyme immunoassay. Data of meat workers were obtained with the aid of a questionnaire. The association of Leptospira exposure with the characteristics of meat workers was analyzed by bivariate and multivariate analyses. Results Anti-Leptospira IgG antibodies were found in 22 (17.7%) of 124 meat workers and in eight (6.5%) of 124 controls (OR = 3.12; 95% CI: 1.33 - 7.33; P = 0.006). Seroprevalence of Leptospira infection was similar between male butchers (17.6%) and female butchers (18.2%) (P = 1.00). Multivariate analysis of socio-demographic, work and behavioral variables showed that Leptospira exposure was associated with duration in the activity, rural residence, and consumption of snake meat and unwashed raw fruits. Conclusions This is the first case-control study of the association of Leptospira exposure with the occupation of meat worker. Results indicate that meat workers represent a risk group for Leptospira exposure. Risk factors for Leptospira exposure found in this study may help in the design of optimal preventive measures against Leptospira infection. PMID:26858797

  12. Molecular Diversity of Vaccine Candidates in Leptospira spp.

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    Patricia Hernández-Rodríguez

    2015-09-01

    Full Text Available The aim of this study was to determine the molecular diversity of OmpL1, LipL32, LipL41, LigA and LigB proteins and that of the genes that encode them using bioinformatic analysis in different pathogenic strains of Leptospira spp. based on the information available in databases. The amino acid sequences of OmpL1, LipL32, LipL41, LigA and LigB proteins were used, as well as the genes encoding them in strains of Leptospira spp. reported at The National Center for Biotechnology Information (NCBI. The analysis of proteins and genes were performed using the Protein, Nucleotide and Gene resources from the NCBI. The alignment of the consensus sequences was performed using the PSI-BLAST and BLASTn tools. The coverage percentage of the selected sequences of the ompL1, lipL32, lipL41, ligA and ligB genes in pathogenic strains of Leptospira spp. is 100% for ompL1, lipL32 and lipL41, 75% for ligA and 99% for ligB with identity percentages of 85, 98, 88, 90 and 80% respectively; the coverage percentage of the selected protein sequences is 100, 77, 99, 100 and 100% with identity percentages of 90, 99, 92, 63 and 60% respectively, indicating that genes and proteins, except LigA and LigB proteins, are highly conserved in various pathogenic serovars of Leptospira spp. According to these results, it is recommended that further analysis of these proteins be made in order to determine the feasibility of its use as vaccine candidates.

  13. Optimization of Culture of Leptospira from Humans with Leptospirosis▿

    Science.gov (United States)

    Wuthiekanun, Vanaporn; Chierakul, Wirongrong; Limmathurotsakul, Direk; Smythe, Lee D.; Symonds, Meegan L.; Dohnt, Michael F.; Slack, Andrew T.; Limpaiboon, Roongreung; Suputtamongkol, Yupin; White, Nicholas J.; Day, Nicholas P. J.; Peacock, Sharon J.

    2007-01-01

    A prospective study of 989 patients with acute febrile illness was performed in northeast Thailand to define the yield of Leptospira from four different types of blood sample. Based on a comparison of the yields from whole blood, surface plasma, deposit from spun plasma, and clotted blood samples from 80 patients with culture-proven leptospirosis, we suggest a sampling strategy in which culture is performed using whole blood and deposit from spun plasma. PMID:17301285

  14. Cross neutralizing antibodies in hamsters vaccinated with leptospiral bacterins produced with three serovars of serogroup Sejroe

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    Rosana Tabata

    2002-09-01

    Full Text Available Three leptospiral bacterins, produced with different serovars of Serogroup Sejroe, namely the hardjo (bacterin A, wolffi (bacterin B and guaricura (bacterin C, were evaluated in male hamsters (Mesocricetus auratus by comparing the agglutinating and neutralizing antibodies titers using microscopic agglutination (MAT and in vitro growth inhibition (GIT tests. The immunization schedule was based on two 1.0 mL doses of non-diluted formalininactivated whole culture bacterin given through subcutaneous route with 10-day interval. The challenge was performed ten days after the second vaccine dose, when the animals were inoculated with 0.2 mL of non-inactivated cultures of each serovar through intraperitoneal route. On the 21st post-challenge day (PCD, all animals were bled and their sera were joined in pools (n=8 and tested by MAT and GIT. All vaccinated and control animals presented no clinical signs of leptospirosis after the challenge, but the serovar guaricura was isolated from the kidneys of control animals on the 21st PCD. The MAT results showed cross agglutinins between serovars hardjo and wolffi, and between wolffi and guaricura. The GIT results revealed the presence of cross neutralizing antibodies between serovars wolffi or guaricura against hardjo, wolffi and guaricura. It was found that the tested strain of serovar hardjo did not produce detectable levels of neutralizing antibodies, indicating its poor immunogenicity.

  15. PEMERIKSAAN BAKTERI LEPTOSPIRA PADA SAMPEL DARAH MANUSIA SUSPECT LEPTOSPIROSIS MENGGUNAKAN METODE PCR (POLYMERASE CHAIN REACTION

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    Sefrita Tri Utami

    2014-01-01

    Full Text Available ABSTRACTLeptospirosis is a zoonotic disease, which is caused by leptospira. Leptospirosis cases often show no specificclinical symptoms and is difficult to diagnose without testing samples in the laboratory. Testing using PCR(Polymerase Chain Reaction is considered more accurate than the other methods. Components required in theexamination Leptospira bacteria in human blood samples using PCR method is DNA template, DNA polymeraseenzyme, forward primer (PU1 and SU1 and reverse primer (Lep R1, nuclease free water, Mg 2 +, and dNTPs.Examination of Leptospira bacteria in human blood samples include sampling, DNA isolation, examination byPCR, and electrophoresis running.Key words: leptospirosis, Leptospira, PCR methodsABSTRAKLeptospirosis adalah penyakit zoonosis yang disebabkan oleh bakteri Leptospira. Kasus leptospirosis seringtidak menunjukkan gejala klinis yang spesifik dan sulit didiagnosis tanpa pengujian sampel di laboratorium.Pengujian dengan menggunakan metode PCR (Polymerase Chain Reaction dinilai lebih akurat dibandingkandengan metode yang lain. Komponen-komponen yang dibutuhkan dalam pemeriksaan bakteri Leptospira padasampel darah manusia menggunakan metode PCR adalah DNA template, enzim polymerase, Primer PU 1 danPrimer SU 1, Primer Lep R1, air, Mg2+ , dan dNTP. Pemeriksaan bakteri Leptospira pada sampel darah manusiameliputi pengambilan sampel, isolasi DNA, pemeriksaan dengan metode PCR, dan running elektroforesis.Kata kunci: leptospirosis, Leptospira, metode PCR

  16. Leptospira Exposure and Patients with Liver Diseases: A Case-Control Seroprevalence Study

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Hernández-Tinoco, Jesús; Ramos-Nevárez, Agar; Margarita Cerrillo-Soto, Sandra; Alberto Guido-Arreola, Carlos

    2016-01-01

    The seroepidemiology of Leptospira infection in patients suffering from liver disease has been poorly studied. Information about risk factors associated with infection in liver disease patients may help in the optimal planning of preventive measures. We sought to determine the association of Leptospira IgG seroprevalence and patients with liver diseases, and to determine the characteristics of the patients with Leptospira exposure. We performed a case-control study of 75 patients suffering from liver diseases and 150 age- and gender-matched control subjects. Diagnoses of liver disease included liver cirrhosis, steatosis, chronic hepatitis, acute hepatitis, and amoebic liver abscess. Sera of participants were analyzed for the presence of anti- Leptospira IgG antibodies using a commercially available enzyme immunoassay. Anti-Leptospira IgG antibodies were found in 17 (22.7%) of 75 patients and in 15 (10.0%) of 150 control subjects (OR = 2.32; 95% CI: 1.09-4.94; P=0.03). This is the first age- and gender-matched case control study about Leptospira seroprevalence in patients with liver diseases. Results indicate that Leptospira infection is associated with chronic and acute liver diseases. Results warrants for additional studies on the role of Leptospira exposure in chronic liver disease. PMID:27493589

  17. Imported Leptospira licerasiae Infection in Traveler Returning to Japan from Brazil.

    Science.gov (United States)

    Tsuboi, Motoyuki; Koizumi, Nobuo; Hayakawa, Kayoko; Kanagawa, Shuzo; Ohmagari, Norio; Kato, Yasuyuki

    2017-03-01

    We describe a case of intermediate leptospirosis resulting from Leptospira licerasiae infection in a traveler returning to Japan from Brazil. Intermediate leptospirosis should be included in the differential diagnosis for travelers with fever returning from South America. This case highlights the need for strategies that detect pathogenic and intermediate Leptospira species.

  18. Development of Chronic and Acute Golden Syrian Hamster Infection Models with Leptospira borgpetersenii serovar Hardjo

    Science.gov (United States)

    The golden Syrian hamster (Mesocricetus auratus) is frequently used as a model to study virulence for several species of Leptospira. Onset of an acute, lethal infection following infection with several pathogenic Leptospira species has been widely adopted for vaccine testing. An important exceptio...

  19. Epidemiological study on human and canine leptospirosis in Central and North Kerala

    Directory of Open Access Journals (Sweden)

    Manju Soman

    2014-10-01

    Full Text Available Aim: The aim was to study the epidemiology of human and animal leptospirosis in Central and Northern Kerala, by isolation techniques and serology. Materials and Methods: Kidney tissues from 35 rodents (11 bandicoots and 24 rats, autopsy specimens from two canines, blood from 15 canines and 30 human beings were subjected to isolation trials for Leptospira. Sera from these animals and human beings were screened for leptospiral antibodies by microscopic agglutination test (MAT. Results: Leptospira could be isolated from human blood as well as from rodent kidney tissues. The MAT could detect the presence of leptospiral antibodies in 54.54% of human sera, 36.36% of dog sera and 21.42% of rodent sera. Pomona and Australis were the most predominant serovars detected in man, dog, and rodents. Tentative serotyping of the isolates by MAT revealed its identity as Leptospira interrogans serovar Pomona. Conclusion: Detection of common serovars of Leptospira in man and animals by serology as well as isolation reiterates the major role played by animals in the epidemiology of human leptospirosis.

  20. SEROLOGIC SURVEY AND RESULTS OF URINARY PCR TESTING FOR LEPTOSPIROSIS IN CAPTIVE BLACK-TAILED PRAIRIE DOGS (CYNOMYS LUDOVICIANUS).

    Science.gov (United States)

    Olds, June E; Sun, Yaxuan; Baum, David H; Gauger, Phillip

    2015-12-01

    Leptospirosis is an important zoonotic disease occurring clinically and subclinically in humans and a wide variety of mammal species worldwide. Often, rodents and wild animals are identified as important reservoirs for the disease. Twenty-two captive black-tailed prairie dogs (Cynomys ludovicianus) housed within a zoo were examined as part of a routine census and preventive medicine program. During examinations, blood and urine were collected to screen for exposure to, or infection with, leptospirosis. All animals were apparently healthy at the time of examination. Leptospira microscopic agglutination test identified 12 of 22 (54.5%) prairie dogs with antibody titers ≥1 : 100 against Leptospira interrogans serovar bratislava on initial serologic examination. All prairie dogs within this collection were serologically negative for L. interrogans serovars canicola, hardjo, icterohaemorrhagiae, and pomona and Leptospira kirschneri serovar grippotyphosa. Leptospira polymerase chain reaction (PCR) testing of urine was negative in all animals tested. This report describes evidence that captive prairie dogs may be exposed to leptospirosis, most likely from wild rodent reservoirs; however, serum titers are low, and lack of leptospiral DNA detected by PCR indicates that these captive animals are unlikely to be important reservoirs for the disease.

  1. Long-term preservation of leptospiras by liquid nitrogen Conservación de leptospiras en nitrógeno líquido

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    C. A. Rossetti

    2008-06-01

    Full Text Available Liquid nitrogen freezing is recommended for long-term preservation of Leptospira serovars. However, there is no standard protocol to follow for this methodology. We herein report a simple procedure to preserve well-characterized Leptospira serovars unaltered for long-term storage in liquid nitrogen. Forty-three (43 leptospira strains, cryoprotected with 10% (v/v glycerol were rapidly frozen in a dry-ice methanol bath and immediately submerged in liquid-nitrogen. Viability was retained in 100%, 93% and 83% of the frozen cultures after 6, 18 and 54 months, following freezing and storage in liquid nitrogen, respectively. Motility and agglutinability were not altered. These results demonstrate the usefulness of this protocol for long-term storage of genus Leptospira in liquid nitrogen.Se recomienda la congelación en nitrógeno líquido para el mantenimiento de cepas de leptospiras a largo plazo. Sin embargo, no existe para ello una metodología de trabajo estandarizada. En este trabajo se presenta y evalúa un protocolo simple para conservar inalteradas cepas de leptospiras en nitrógeno líquido durante largo tiempo. Cuarenta y tres (43 cepas de leptospiras crioprotegidas con glicerol al 10% (v/v fueron rápidamente congeladas en un baño de metanol y hielo seco, e inmediatamente sumergidas en nitrógeno líquido. Fue posible recuperar el 100%, 93% y 83% de los cultivos congelados a los 6, 18 y 54 meses poscongelación, respectivamente, sin observarse alteración en la movilidad ni en la aglutinabilidad de las cepas recuperadas. Estos resultados demuestran la utilidad del protocolo presentado para conservar cepas del género Leptospira en nitrógeno líquido durante largos períodos de tiempo.

  2. Comparison of conventional PCR, quantitative PCR, bacteriological culture and the Warthin Starry technique to detect Leptospira spp. in kidney and liver samples from naturally infected sheep from Brazil.

    Science.gov (United States)

    Fornazari, Felipe; da Silva, Rodrigo Costa; Richini-Pereira, Virginia Bodelão; Beserra, Hugo Enrique Orsini; Luvizotto, Maria Cecília Rui; Langoni, Helio

    2012-09-01

    Leptospirosis is an infectious disease of worldwide importance. The development of diagnostic techniques allows sick animals to be identified, reservoirs to be eliminated and the disease prevented and controlled. The present study aimed to compare different techniques for diagnosing leptospirosis in sheep. Samples of kidney, liver and blood were collected from 465 animals that originated from a slaughterhouse. The sera were analyzed by the Microscopic Agglutination Test (MAT), and kidney and liver samples of seropositive animals were analyzed using four techniques: bacteriological culture, the Warthin Starry (WS) technique, conventional PCR (cPCR), and quantitative PCR (qPCR). With the MAT, 21 animals were positive (4.5%) to serovars Hardjo (n=12), Hebdomadis (n=5), Sentot (n=2), Wolfii (n=1) and Shermani (n=1). Titers were 100 (n=10), 200 (n=2), 400 (n=6) and 1600 (n=3). No animal was positive by bacteriological culture; four animals were positive by the WS technique in kidney samples; six animals were positive by cPCR in kidney samples; and 11 animals were positive by qPCR, eight of which in kidney samples and three in liver. The bacterial quantification revealed a median of 4.3 bacteria/μL in liver samples and 36.6 bacteria/μL in kidney samples. qPCR presented the highest sensitivity among the techniques, followed by cPCR, the WS technique and bacteriological culture. These results indicate that sheep can carry leptospires of the Sejroe serogroup, and demonstrate the efficiency of quantitative PCR to detect Leptospira spp. in tissue samples.

  3. Emergence of new leptospiral serovars in American Samoa - ascertainment or ecological change?

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    Lau Colleen L

    2012-01-01

    Full Text Available Abstract Background Leptospirosis has recently been discussed as an emerging infectious disease in many contexts, including changes in environmental drivers of disease transmission and the emergence of serovars. In this paper, we report the epidemiology of leptospiral serovars from our study of human leptospirosis in American Samoa in 2010, present evidence of recent serovar emergence, and discuss the potential epidemiological and ecological implications of our findings. Methods Serovar epidemiology from our leptospirosis seroprevalence study in 2010 was compared to findings from a study in 2004. The variation in geographic distribution of the three most common serovars was explored by mapping sero-positive participants to their place of residence using geographic information systems. The relationship between serovar distribution and ecological zones was examined using geo-referenced data on vegetation type and population distribution. Results Human leptospirosis seroprevalence in American Samoa was 15.5% in 2010, with serological evidence that infection was caused by three predominant serovars (Hebdomadis, LT 751, and LT 1163. These serovars differed from those identified in an earlier study in 2004, and were not previously known to occur in American Samoa. In 2010, serovars also differed in geographic distribution, with variations in seroprevalence between islands and different ecological zones within the main island. Conclusions Our findings might indicate artefactual emergence (where serovars were long established but previously undetected, but we believe the evidence is more in favour of true emergence (a result of ecological change. Possibilities include changes in interactions between humans and the environment; introduction of serovars through transport of animals; evolution in distribution and/or abundance of animal reservoirs; and environmental changes that favour transmission of particular serovars. Future research should explore the

  4. Opportunities and strategies to further reduce animal use for Leptospira vaccine potency testing.

    Science.gov (United States)

    Walker, A; Srinivas, G B

    2013-09-01

    Hamsters are routinely infected with virulent Leptospira for two purposes in the regulation of biologics: the performance of Codified potency tests and maintenance of challenge culture for the Codified potency tests. Options for reducing animal use in these processes were explored in a plenary lecture at the "International Workshop on Alternative Methods for Leptospira Vaccine Potency Testing: State of the Science and the Way Forward" held at the Center for Veterinary Biologics in September 2012. The use of validated in vitro potency assays such as those developed by the U.S. Department of Agriculture for Leptospira (L.) canicola, Leptospira grippotyphosa, Leptospira pomona, and Leptospira icterohaemorrhagiae rather than the Codified hamster vaccination-challenge assay was encouraged. Alternatives such as reduced animal numbers in the hamster vaccination-challenge testing were considered for problematic situations. Specifically, the merits of sharing challenge controls, reducing group sizes, and eliminating animals for concurrent challenge dose titration were assessed. Options for maintaining virulent, stable cultures without serial passage through hamsters or with decreased hamster use were also discussed. The maintenance of virulent Leptospira without the use of live animals is especially difficult since a reliable means to maintain virulence after multiple in vitro passages has not yet been identified. Published by Elsevier Ltd.

  5. Main aspects of Leptospira sp infection in sheep

    OpenAIRE

    Luiza de Souza Seixas Melo; Márcio Botelho de Castro; Rômulo Cerqueira Leite; Élvio Carlos Moreira; Cristiano Barros Melo

    2010-01-01

    Este trabalho tem como objetivo revisar as infecções por Leptospira sp em ovinos. São abordados os aspectos epidemiológicos, incluindo a ocorrência no Brasil e as formas de transmissão, os sinais clínicos e as lesões, o diagnóstico e as medidas de prevenção e controle. _______________________________________________________________________________ ABSTRACT An updated review of Leptopspira sp infection in sheep is presented emphasizing some epidemiological aspects including the occurrence o...

  6. Impact of environment and social gradient on Leptospira infection in urban slums.

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    Renato B Reis

    Full Text Available BACKGROUND: Leptospirosis has become an urban health problem as slum settlements have expanded worldwide. Efforts to identify interventions for urban leptospirosis have been hampered by the lack of population-based information on Leptospira transmission determinants. The aim of the study was to estimate the prevalence of Leptospira infection and identify risk factors for infection in the urban slum setting. METHODS AND FINDINGS: We performed a community-based survey of 3,171 slum residents from Salvador, Brazil. Leptospira agglutinating antibodies were measured as a marker for prior infection. Poisson regression models evaluated the association between the presence of Leptospira antibodies and environmental attributes obtained from Geographical Information System surveys and indicators of socioeconomic status and exposures for individuals. Overall prevalence of Leptospira antibodies was 15.4% (95% confidence interval [CI], 14.0-16.8. Households of subjects with Leptospira antibodies clustered in squatter areas at the bottom of valleys. The risk of acquiring Leptospira antibodies was associated with household environmental factors such as residence in flood-risk regions with open sewers (prevalence ratio [PR] 1.42, 95% CI 1.14-1.75 and proximity to accumulated refuse (1.43, 1.04-1.88, sighting rats (1.32, 1.10-1.58, and the presence of chickens (1.26, 1.05-1.51. Furthermore, low income and black race (1.25, 1.03-1.50 were independent risk factors. An increase of US$1 per day in per capita household income was associated with an 11% (95% CI 5%-18% decrease in infection risk. CONCLUSIONS: Deficiencies in the sanitation infrastructure where slum inhabitants reside were found to be environmental sources of Leptospira transmission. Even after controlling for environmental factors, differences in socioeconomic status contributed to the risk of Leptospira infection, indicating that effective prevention of leptospirosis may need to address the social

  7. Patterns in Leptospira Shedding in Norway Rats (Rattus norvegicus from Brazilian Slum Communities at High Risk of Disease Transmission.

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    Federico Costa

    Full Text Available We address some critical but unknown parameters of individuals and populations of Norway rats (Rattus norvegicus that influence leptospiral infection, maintenance and spirochetal loads shed in urine, which contaminates the environment ultimately leading to human infection.Our study, conducted in Salvador, Brazil, established the average load of leptospires in positive kidneys to be 5.9 x 10(6 per mL (range 3.1-8.2 x10(6 genome equivalents (GEq, similar to the 6.1 x 10(6 per ml (range 2.2-9.4 x10(6 average obtained from paired urines, with a significant positive correlation (R2=0.78 between the two. Based on bivariate and multivariate modeling, we found with both kidney and urine samples that leptospiral loads increased with the age of rats (based on the index of body length to mass, MAT titer and the presence of wounding/scars, and varied with site of capture. Some associations were modified by sex but trends were apparent. Combining with data on the demographic properties and prevalence of leptospiral carriage in rat populations in Salvador, we estimated that daily leptospiral loads shed in the urine of a population of 82 individuals exceeded 9.1 x 10(10 leptospires.These factors directly influence the risk of leptospiral acquisition among humans and provide essential epidemiological information linking properties of rat populations with risk of human infection.

  8. Effectiveness of a commercial leptospiral vaccine on urinary shedding in naturally exposed sheep in New Zealand.

    Science.gov (United States)

    Vallée, Emilie; Ridler, Anne L; Heuer, Cord; Collins-Emerson, Julie M; Benschop, Jackie; Wilson, Peter R

    2017-03-01

    L. borgpetersenii serovar Hardjo and L. interrogans serovar Pomona are endemic in New Zealand sheep. An effective vaccine and vaccination strategy would protect both humans and livestock. Four to 12 lambs were selected from each of eight farms (total=84, vaccinated group), while four to 16 lambs (total=98) served as unvaccinated controls. A commercial Hardjo/Pomona vaccine was given at 1-6 weeks of age, 5-11 weeks later and 33-67 weeks later on seven farms and at 18 weeks of age and 5 weeks later on the eighth farm. Vaccinates and controls were grazed together. Blood was regularly collected from the control group to assess flock exposure. Urine was collected from both groups 26-82 weeks after the second vaccination and tested by quantitative PCR. Seroprevalence in controls at the time of urine sampling ranged from 2.7 to 98.2% for Hardjo and from 0 to 54.1% for Pomona with seroconversion occurring 13 to 67 weeks after the second vaccination in all but one farm where exposure had happened by the time of vaccination. The shedding prevalence adjusted for clustering in farms was 45.1% [95% CI 17.6-72.7] (for an observed number of 50/98) in the control animals and 1.8% [95% CI 0.0-10.1] (for an observed number of 5/84) in the vaccinated animals. The vaccine was 100% effective on five farms where animals were vaccinated before 12 weeks of age and before natural exposure occurred, but the effectiveness was 80% [0-97] on one farm where the lambs were exposed before vaccination and 65% [9-87] to 80% [0-97] on one farm where the animals were fully vaccinated by 24 weeks of age. The overall vaccine effectiveness was 86.3% [63.6-94.8%] despite maternal antibodies in some flocks at first vaccination. Vaccination timing seemed to be crucial in achieving optimum reduction in shedding in urine in vaccinated sheep. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Seroprevalence of Brucella abortus and Leptospira hardjo in cattle

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    S. Jegaveera Pandian

    2015-02-01

    Full Text Available Aim: The aim was to assess the seroprevalence of B. abortus and Leptospira hardjo in the cattle population of Bihar, this work was carried out. Materials and Methods: Randomly selected 450 cattle from nine districts of Bihar were serologically screened for antibodies against L. hardjo and B. abortus. DAS-ELISA for leptospira and AB-ELISA for brucella were carried out. Based on the results prevalence in each district and the state are reported herewith. Results: In this study, it was found that the seroprevalence of L. hardjo was 9.11% and that of B. abortus was 12.2% in Bihar. Indigenous cattle were found to be less susceptible to leptospirosis and brucellosis even though they accounted for 83.11% of the study population. Conclusion: Although there was no acute disease, antibodies detected against L. hardjo and B. abortus in the cattle population indicated the presence of chronic and subclinical infection, which could challenge the fertility of the animals.

  10. High-resolution melt-curve analysis of random amplified polymorphic DNA (RAPD-HRM) for the characterisation of pathogenic leptospires

    DEFF Research Database (Denmark)

    Tulsiani, Suhella; Craig, S B; Graham, G C;

    2010-01-01

    High-resolution melt-curve analysis of random amplified polymorphic DNA (RAPD-HRM) is a novel technology that has emerged as a possible method to characterise leptospires to serovar level. RAPD-HRM has recently been used to measure intra-serovar convergence between strains of the same serovar...

  11. Leptospira sp em ovinos do Rio Grande do Sul soroprevalência e avaliação da imunogenicidade da bacterina leptospira hardjo

    OpenAIRE

    Geder Paulo Herrmann

    2002-01-01

    Foi determinada a soroprevalência de aglunininas anti-leptospira sp, em 1360 amostras de soros de ovinos, das messorregiãoes Sudeste e Sudoeste Rio-Grandense, entre os meses de janeiro a marco de 199. A maior soroprevalência da Leptospira sp, com maior frequencia a sorovariedade hardjo, elaborou-se de uma vacina monovalente L hardjo, como adjuvante oleoso, aplicada em dois grupos de ovinos formado por 15 ovelhas e um terceiro controle formado por 10 animais. O primeiro grupo recebeu duas dose...

  12. Amino acid sequences of proteins from Leptospira serovar pomona

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    Alves Selmo F

    2000-01-01

    Full Text Available This report describes a partial amino acid sequences from three putative outer envelope proteins from Leptospira serovar pomona. In order to obtain internal fragments for protein sequencing, enzymatic and chemical digestion was performed. The enzyme clostripain was used to digest the proteins 32 and 45 kDa. In situ digestion of 40 kDa molecular weight protein was accomplished using cyanogen bromide. The 32 kDa protein generated two fragments, one of 21 kDa and another of 10 kDa that yielded five residues. A fragment of 24 kDa that yielded nineteen residues of amino acids was obtained from 45 kDa protein. A fragment with a molecular weight of 20 kDa, yielding a twenty amino acids sequence from the 40 kDa protein.

  13. Seroprevalence and factors associated with Leptospira infection in an urban district of Cali, Colombia

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    Kevin Escandón-Vargas

    Full Text Available Few studies have addressed Leptospira seroprevalence and risk factors in urban populations in Colombia. This study aimed to determine seroprevalence and factors associated with Leptospira infection in inhabitants of an urban district of Cali, Colombia. We collected sociodemographic and environmental data, as well as blood samples, from 353 subjects selected through a multistage cluster sampling design. We performed microagglutination test for the eight main Leptospira serogroups circulating in the region, considering a cut-off titer of ≥ 1:100. Most participants were female (226, 64.8%, with mean age 41.4 years, and 89 (32.6% lived in low-low socioeconomic stratum (SES-1. Overall seroprevalence was 12.2% (95%CI: 10.3%-14.4%. Factors associated with Leptospira infection were SES 1, older age, single marital status, ethnic groups (Afro-Colombian and white/mestizo, school students, absence of toilet, barefoot walking, travel outside Cali in the previous month, and absence of skin and mucous-membrane lesions in the previous month. Our study suggests domestic and peridomiciliary transmission of Leptospira likely related to activities of daily living and inadequate environmental conditions. SES-1 is a major factor associated with Leptospira infection (adjusted OR = 4.08; 95%CI: 2.54-6.53; p < 0.001, suggesting that social and environmental conditions are key elements for endemicity of Leptospira infection in the study area. Epidemiological surveillance, improvement of environmental and sanitary conditions in various SES-1 areas, and community educational campaigns are recommended.

  14. Leptospira Contamination in Household and Environmental Water in Rural Communities in Southern Chile

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    Claudia Muñoz-Zanzi

    2014-06-01

    Full Text Available Leptospirosis is a zoonosis of global distribution that affects tropical and temperate areas. Under suitable conditions, Leptospira can survive in water and soil and contribute to human and animal infections. The objective of this study was to describe the presence of pathogenic Leptospira in peri-domestic water samples from rural households in southern Chile. Water samples, including puddles, containers, animal troughs, rivers, canals, and drinking water were collected from 236 households and tested for Leptospira using a PCR assay targeting the lipL32 gene. Evidence of Leptospira presence was detected in all sample types; overall, 13.5% (77/570 samples tested positive. A total of 10/22 (45.5% open containers, 12/83 (14.5% animal drinking sources, 9/47 (19.1% human drinking sources, and 36/306 (19.3% puddles tested positive. Lower income (OR = 4.35, p = 0.003, increased temperature (OR = 1.23, p < 0.001, and presence of dogs (OR = 15.9, p = 0.022 were positively associated with positive puddles. Increased number of rodent signs was associated with positive puddles in the household (OR = 3.22; however, only in the lower income households. There was no association between PCR positive rodents and puddles at the household level. Results revealed the ubiquity of Leptospira in the household environment and highlight the need to develop formal approaches for systematic monitoring.

  15. Leptospira and Brucella antibodies in collared anteaters (Tamandua tetradactyla) in Brazilian zoos.

    Science.gov (United States)

    Sales, Indiara dos Santos; Folly, Márcio Manhães; Garcia, Luize Néli Nunes; Ramos, Tatiane Mendes Varela; da Silva, Mariana Cristina; Pereira, Martha Maria

    2012-12-01

    The presence of Leptospira spp. and Brucella spp. antibodies was investigated in serum samples from 28 collared anteaters (Tamandua tetradactyla) kept in seven Brazilian zoos. Sera were tested against 19 Leptospira serovars using microscopic agglutination. Samples reacted to the following serovars: two (7.14%) to Patoc, three (10.71%) to Tarrasovi, three (10.71%) to both Patoc and Tarrasovi, two (7.14%) to Wolffi, and one (3.57%) to Australis. Two (7.14%) samples reacted to the buffered Brucella antigen test, but no confirmatory reaction occurred using the 2-mercaptoethanol slow slide agglutination test. No sample was reactive in the agar gel immunodiffusion test for rugose species of Brucella. The presence of anti-leptospira agglutinins in captive T. tetradactyla serum indicates that this species may be susceptible to infection by these bacteria.

  16. Detection of Leptospira DNA in urine and presence of specific antibodies in outdoor cats in Germany.

    Science.gov (United States)

    Weis, Sonia; Rettinger, Anna; Bergmann, Michele; Llewellyn, Julia R; Pantchev, Nikola; Straubinger, Reinhard K; Hartmann, Katrin

    2017-04-01

    Objectives Clinical manifestation of infection with Leptospira species in cats is rare. Nevertheless, cats can develop specific antibodies against the spirochetes after infection. In Canada, Taiwan and the USA it was recently demonstrated that naturally infected cats can also shed DNA from pathogenic Leptospira species in their urine, but the zoonotic potential of infected cats is still unclear. The objective of this study was to demonstrate if outdoor cats in Germany shed DNA from pathogenic Leptospira species in their urine. As a second aim, antibody prevalence was determined. Methods Two hundred and fifteen outdoor cats were prospectively recruited. Urine samples were tested by real-time PCR targeting the lipL32 gene of pathogenic Leptospira species. Antibody titres against eight serovars (Australis, Autumnalis, Bratislava, Canicola, Copenhageni, Grippotyphosa, Pomona, Saxkoebing) belonging to seven serogroups (Australis, Autumnalis, Canicola, Grippotyphosa, Icterohaemorrhagiae, Pomona, Sejroe) were determined by microscopic agglutination test. Results Urine samples from 7/215 cats (3.3%; 95% confidence interval [CI] 0.9-5.7) were PCR-positive. Specific antibodies were detected in 35/195 cats (17.9%; 95% CI: 12.5-23.3) with titres ranging from 1:100 to 1:6400. Australis, Bratislava and Grippotyphosa were the most common serovars. Conclusions and relevance Outdoor cats in Germany can shed DNA from pathogenic Leptospira species. Therefore, outdoor cats should be considered as a possible source of infection for dogs or humans. Further studies are needed to determine the role of Leptospira species as a cause of disease in cats.

  17. Frequency of Leptospira spp. in sheep from Brazilian slaughterhouses and its association with epidemiological variables

    OpenAIRE

    Rodrigo Costa da Silva; Veruska Maia da Costa; Fabio Hiroto Shimabukuro; Virgínia Bodelão Richini-Pereira; Benedito Donizete Menozzi; Hélio Langoni

    2012-01-01

    A leptospirose é uma antropozoonose mundialmente distribuída que infecta animais de produção, incluindo as ovelhas como carreadores para outros animais e o homem. O presente estudo objetivou determinar a prevalência de Leptospira spp. em ovinos de dois abatedouros do estado de São Paulo e sua associação com algumas variáveis epidemiológicas estudadas. Amostras de soro de 182 ovinos foram pesquisadas para a presença de anticorpos para Leptospira spp. pela soroaglutinação microscópica (SAM). Os...

  18. Anti-Leptospira sp. agglutinins in ewes in the Federal District, Brazil.

    Science.gov (United States)

    Seixas, Luiza de S; de Melo, Cristiano Barros; Leite, Rômulo C; Moreira, Elvio C; McManus, Concepta M; de Castro, Márcio B

    2011-01-01

    To define the prevalence of anti-Leptospira sp. agglutinins in ewes in the Federal District, Brazil, serum samples from 157 ewes were tested for antibodies against serovars of Leptospira sp. by the microscopic agglutination test. Antibodies were detected in three flocks in a prevalence of 3% (95% CI = 0.4%-5.7%). Considering that sheep and cattle were raised together, the lack of sanitary control could represent a risk to cattle production, which is the most important activity in the Centre-West region of Brazil.

  19. [Use of culture media with sheep serum for maintenance and isolation of Leptospira strains].

    Science.gov (United States)

    Nicolescu, M; Moldoveanu, G

    1976-01-01

    A study was carried out on the effects of a culture medium prepared with sheep serum inactivated at 68 degrees C on Leptospira cultures. Good results were obtained showing that the medium with sheep serum can be used for the cultivation of Leptospira in view of the preparation of antigens for microscopic agglutination and complement fixation. In experiments on the isolation of germs from organocultures and haemocultures the proportion of positive results obtained with sheep serum was smaller than with the media containing rabbit serum.

  20. Frequency of Leptospira spp in pigs from commercial farms and backyard breeding slaughtered in two abattoirs of Lima

    OpenAIRE

    Anampa V., Luis; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima. Perú; Rivera G., Hermelinda; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Falcón P., Néstor; Facultad de Veterinaria y Zootecnia, Universidad Peruana Cayetano Heredia, Lima; Arainga R., Mariluz; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Ramírez V., Mercy; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima

    2012-01-01

    The objective of this study was to determine the frequency of antibodies against Leptospira spp in pigs reared in five well-managed farms (n=163) and from 11 backyard breeding (n=133) owners in the Lima valley, Peru. Blood samples (n=296) were collected in two slaughterhouses for antibody detection against eight serovars of Leptospira by microaglutination test. The 85.8 ± 3.9% (254/296) of samples had antibodies against one or more serovars of Leptospira. The 89.6 ± 4.7% (146/163) and 82.1 ± ...

  1. Pesquisa de aglutininas, antígeno de leptospiras e apoptose em rim de suínos naturalmente infectados por Leptospira spp.

    Directory of Open Access Journals (Sweden)

    Larissa M.F. Gonçalves

    2011-07-01

    Full Text Available Soro e rim de 75 suínos mestiços sem raça definida, criados em sistema extensivo e abatidos em Timon (MA e Teresina (Piauí, Brasil, duas cidades separadas pelo Rio Parnaíba e 75 suínos mestiços de um sistema de criação em confinamento, filhos de Landrace, Large White e/ou Duroc foram utilizados neste estudo. Das 150 amostras analisadas pela prova de Soroaglutinação Microscópica (SAM, sete foram reagentes e o sorovar Icterohaemorrhagiae (42,86% foi o mais frequente. Uma comparação entre os dois sistemas para examinar uma predisposição para infecção para Leptospira spp. mostrou que a suscetibilidade foi maior nos animais criados extensivamente do que naqueles criados em confinamento (teste χ2, p<0,05. A presença de infiltrado inflamatório foi significantemente maior nos animais soropositivos comparados aos soronegativos (p<0,05, Teste U de Mann-Whitney. A análise morfométrica mostrou Leptospira spp. e o antígeno de leptospira apenas nos animais soropositivos (p<0,05, teste de U de Mann-Whitney. Apoptose em células epiteliais tubulares foi significantemente mais evidente nos animais infectados comparados aos não infectados (p<0,05, Teste U de Mann-Whitney. Uma eventual associação de antígeno de Leptospira e células epiteliais em apoptose sugere um provável mecanismo de lesão renal na leptospirose suína.

  2. Acute Interstitial Nephritis due to Leptospira grippotyphosa in the Absence of Weil’s Disease

    Directory of Open Access Journals (Sweden)

    Tanja Schmidhauser

    2013-01-01

    Full Text Available Anicteric leptospirosis is a self-limited flu-like disease, whereas the icteric form is a severe illness characterized by multiple organ involvement or even failure. A case involving a patient with rapidly progressing renal insufficiency requiring intermittent renal replacement therapy due to Leptospira grippotyphosa in the absence of a Weil’s disease is reported.

  3. Detection of Brucella sp. and Leptospira sp. in dogs using conventional polymerase chain reaction

    Directory of Open Access Journals (Sweden)

    Khamesipour Faham

    2014-12-01

    Full Text Available The study was conducted to detect Brucella sp. and Leptospira sp. in blood samples of dogs in Isfahan and Shahrekord province in Iran. A total of 94 blood samples were collected from dogs of different breed, age, sex, and dogs’ type (stray or nonstray. The samples were examined using conventional polymerase chain reaction (PCR. Fourteen (14.89% dogs were positive for Brucella sp. and 18 (19.15%. dogs for Leptospira sp. There were no significant differences between the prevalence of the pathogens, provinces, sex, and age groups (P > 0.05. However, there was a statistically significant difference in prevalence of Brucella sp. and Leptospira sp. between stray and non-stray dogs (P < 0.0001; χ2 = 30.3767. The study also demonstrated that PCR was successfully used for the first time in Iran for the detection of Brucella sp. and Leptospira sp. in blood samples of dogs. Therefore, we recommend the PCR as a supplementary method with other commonly recognised methods (e.g. serological methods for the diagnosis of subclinical infections with the microorganisms. Strict measures for the control of stray dogs are also highly recommended.

  4. First report of Leptospira infections in red deer, roe deer, and fallow deer in Poland

    Directory of Open Access Journals (Sweden)

    Żmudzki Jacek

    2016-09-01

    Full Text Available Introduction: Recently in Europe an increase in the population of red deer (Cervus elaphus, roe deer (Capreolus capreolus, and fallow deer (Dama dama has been observed. Research on the prevalence of Leptospira infections in Polish cervids has been performed for the first time.

  5. Colony-level assessment of Brucella and Leptospira in the Guadalupe fur seal, Isla Guadalupe, Mexico.

    Science.gov (United States)

    Ziehl-Quirós, E Carolina; García-Aguilar, María C; Mellink, Eric

    2017-01-24

    The relatively small population size and restricted distribution of the Guadalupe fur seal Arctocephalus townsendi could make it highly vulnerable to infectious diseases. We performed a colony-level assessment in this species of the prevalence and presence of Brucella spp. and Leptospira spp., pathogenic bacteria that have been reported in several pinniped species worldwide. Forty-six serum samples were collected in 2014 from pups at Isla Guadalupe, the only place where the species effectively reproduces. Samples were tested for Brucella using 3 consecutive serological tests, and for Leptospira using the microscopic agglutination test. For each bacterium, a Bayesian approach was used to estimate prevalence to exposure, and an epidemiological model was used to test the null hypothesis that the bacterium was present in the colony. No serum sample tested positive for Brucella, and the statistical analyses concluded that the colony was bacterium-free with a 96.3% confidence level. However, a Brucella surveillance program would be highly recommendable. Twelve samples were positive (titers 1:50) to 1 or more serovars of Leptospira. The prevalence was calculated at 27.1% (95% credible interval: 15.6-40.3%), and the posterior analyses indicated that the colony was not Leptospira-free with a 100% confidence level. Serovars Icterohaemorrhagiae, Canicola, and Bratislava were detected, but only further research can unveil whether they affect the fur seal population.

  6. Development of Hamster Models for Acute and Chronic Infections with Leptospira borgpetersenii serovar Hardjo

    Science.gov (United States)

    The Golden Syrian hamster is frequently used as a small animal model to study acute leptospirosis. However, use of this small animal model to study Leptospira borgpetersenii serovar Hardjo infections has not been well documented. Cattle are the normal maintenance hosts of L. borgpetersenii serovar...

  7. Leptospira Seroprevalence and Risk Factors in Health Centre Patients in Hoima District, Western Uganda.

    Directory of Open Access Journals (Sweden)

    Anou Dreyfus

    2016-08-01

    Full Text Available The burden of human leptospirosis in Uganda is unknown. We estimated the seroprevalence of Leptospira antibodies, probable acute/recent leptospirosis, and risk factors for seropositivity in humans in rural Western Uganda.359 non-pregnant adults visiting the Kikuube and Kigorobya Health Centers were sequentially recruited during March and April 2014. A health history survey and serum were collected from consented participants. Overall, 69% reported having fever in the past year, with 49% reporting malaria, 14% malaria relapse, 6% typhoid fever, 3% brucellosis, and 0% leptospirosis. We tested sera by microscopic agglutination test (MAT against eight Leptospira serovars representing seven serogroups. Leptospira seroprevalence was 35% (126/359; 95%CI 30.2-40.3% defined as MAT titer ≥ 1:100 for any serovar. The highest prevalence was against L. borgpetersenii Nigeria (serogroup Pyrogenes at 19.8% (71/359; 95%CI 15.9-24.4%. The prevalence of probable recent leptospirosis (MAT titer ≥1:800 was 1.9% (95%CI 0.9-4.2% and uniquely related to serovar Nigeria (serogroup Pyrogenes. Probable recent leptospirosis was associated with having self-reported malaria within the past year (p = 0.048. Higher risk activities included skinning cattle (n = 6 with 12.3 higher odds (95%CI 1.4-108.6; p = 0.024 of Leptospira seropositivity compared with those who had not. Participants living in close proximity to monkeys (n = 229 had 1.92 higher odds (95%CI 1.2-3.1; p = 0.009 of seropositivity compared with participants without monkeys nearby.The 35% prevalence of Leptospira antibodies suggests that exposure to leptospirosis is common in rural Uganda, in particular the Nigeria serovar (Pyrogenes serogroup. Leptospirosis should be a diagnostic consideration in febrile illness and "smear-negative malaria" in rural East Africa.

  8. Leptospira Seroprevalence and Risk Factors in Health Centre Patients in Hoima District, Western Uganda

    Science.gov (United States)

    Pearson, Raewynne; Kankya, Clovice; Kajura, Charles; Alinaitwe, Lordrick; Kakooza, Steven; Pelican, Katharine M.; Travis, Dominic A.; Mahero, Michael; Boulware, David R.; Mugisha, Lawrence

    2016-01-01

    Background The burden of human leptospirosis in Uganda is unknown. We estimated the seroprevalence of Leptospira antibodies, probable acute/recent leptospirosis, and risk factors for seropositivity in humans in rural Western Uganda. Methodology and Principal Findings 359 non-pregnant adults visiting the Kikuube and Kigorobya Health Centers were sequentially recruited during March and April 2014. A health history survey and serum were collected from consented participants. Overall, 69% reported having fever in the past year, with 49% reporting malaria, 14% malaria relapse, 6% typhoid fever, 3% brucellosis, and 0% leptospirosis. We tested sera by microscopic agglutination test (MAT) against eight Leptospira serovars representing seven serogroups. Leptospira seroprevalence was 35% (126/359; 95%CI 30.2–40.3%) defined as MAT titer ≥ 1:100 for any serovar. The highest prevalence was against L. borgpetersenii Nigeria (serogroup Pyrogenes) at 19.8% (71/359; 95%CI 15.9–24.4%). The prevalence of probable recent leptospirosis (MAT titer ≥1:800) was 1.9% (95%CI 0.9–4.2%) and uniquely related to serovar Nigeria (serogroup Pyrogenes). Probable recent leptospirosis was associated with having self-reported malaria within the past year (p = 0.048). Higher risk activities included skinning cattle (n = 6) with 12.3 higher odds (95%CI 1.4–108.6; p = 0.024) of Leptospira seropositivity compared with those who had not. Participants living in close proximity to monkeys (n = 229) had 1.92 higher odds (95%CI 1.2–3.1; p = 0.009) of seropositivity compared with participants without monkeys nearby. Conclusions/Significance The 35% prevalence of Leptospira antibodies suggests that exposure to leptospirosis is common in rural Uganda, in particular the Nigeria serovar (Pyrogenes serogroup). Leptospirosis should be a diagnostic consideration in febrile illness and “smear-negative malaria” in rural East Africa. PMID:27487398

  9. Sero-Prevalence and Risk Factors for Leptospirosis in Abattoir Workers in New Zealand

    Directory of Open Access Journals (Sweden)

    Anou Dreyfus

    2014-02-01

    Full Text Available Leptospirosis is an important occupational disease in New Zealand. The objectives of this study were to determine risk factors for sero-prevalence of leptospiral antibodies in abattoir workers. Sera were collected from 567 abattoir workers and tested by microscopic agglutination for Leptospira interrogans sv. Pomona and Leptospira borgpetersenii sv. Hardjobovis. Association between prevalence and risk factors were determined by species specific multivariable analysis. Eleven percent of workers had antibodies against Hardjobovis or/and Pomona. Workers from the four sheep abattoirs had an average sero-prevalence of 10%–31%, from the two deer abattoirs 17%–19% and the two beef abattoirs 5%. The strongest risk factor for sero-positivity in sheep and deer abattoirs was work position. In sheep abattoirs, prevalence was highest at stunning and hide removal, followed by removal of the bladder and kidneys. Wearing personal protective equipment such as gloves and facemasks did not appear to protect against infection. Home slaughtering, farming or hunting were not significantly associated with sero-prevalence. There is substantial risk of exposure to leptospires in sheep and deer abattoirs in New Zealand and a persisting, but lower risk, in beef abattoirs. Interventions, such as animal vaccination, appear necessary to control leptospirosis as an occupational disease in New Zealand.

  10. Sero-prevalence and risk factors for leptospirosis in abattoir workers in New Zealand.

    Science.gov (United States)

    Dreyfus, Anou; Benschop, Jackie; Collins-Emerson, Julie; Wilson, Peter; Baker, Michael G; Heuer, Cord

    2014-02-05

    Leptospirosis is an important occupational disease in New Zealand. The objectives of this study were to determine risk factors for sero-prevalence of leptospiral antibodies in abattoir workers. Sera were collected from 567 abattoir workers and tested by microscopic agglutination for Leptospira interrogans sv. Pomona and Leptospira borgpetersenii sv. Hardjobovis. Association between prevalence and risk factors were determined by species specific multivariable analysis. Eleven percent of workers had antibodies against Hardjobovis or/and Pomona. Workers from the four sheep abattoirs had an average sero-prevalence of 10%-31%, from the two deer abattoirs 17%-19% and the two beef abattoirs 5%. The strongest risk factor for sero-positivity in sheep and deer abattoirs was work position. In sheep abattoirs, prevalence was highest at stunning and hide removal, followed by removal of the bladder and kidneys. Wearing personal protective equipment such as gloves and facemasks did not appear to protect against infection. Home slaughtering, farming or hunting were not significantly associated with sero-prevalence. There is substantial risk of exposure to leptospires in sheep and deer abattoirs in New Zealand and a persisting, but lower risk, in beef abattoirs. Interventions, such as animal vaccination, appear necessary to control leptospirosis as an occupational disease in New Zealand.

  11. Frecuencia de Leptospira spp en porcinos de crianza tecnificada y de traspatio beneficiados en dos mataderos de Lima

    National Research Council Canada - National Science Library

    Anampa V., Luis; Rivera G., Hermelinda; Falcon P., Nestor; Arainga R., Mariluz; Ramirez V., Mercy

    2012-01-01

    El objetivo del estudio fue determinar la frecuencia de anticuerpos contra Leptospira spp en porcinos provenientes de crianza tecnificada (5 granjas, n = 163) y de traspatio (11 criaderos, n = 133) del valle de Lima...

  12. Evidence of leptospirosis in the kidneys and serum of feral swine (Sus scrofa) in the United States.

    Science.gov (United States)

    Pedersen, K; Anderson, T D; Bevins, S N; Pabilonia, K L; Whitley, P N; Virchow, D R; Gidlewski, T

    2017-01-01

    Leptospirosis is the most widespread zoonosis in humans worldwide. In the United States, widespread detection of antibodies to leptospirosis have been identified in feral swine (Sus scrofa) with the highest detection of serovars, Bratislava, Icterohaemorrhagiae, and Pomona. Over the past few years, feral swine populations have expanded their geographical range and distribution in the United States with reports in at least 39 of 50 states. Since feral swine serve as reservoirs for serovars that can infect humans, it is important to understand the risk of transmission. In order to learn more about the probability that feral swine shed infectious leptospires, we collected kidneys and paired serum when possible from 677 feral swine in 124 counties of 29 states. These counties had previously been identified as antibody positive for Leptospira interrogans serovars Bratislava, Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae or Pomona. Although exposure to these same six serovars of leptospirosis continued to be high (53% overall) in the counties we sampled, we detected leptospiral DNA in only 3·4% of feral swine kidneys tested. Based on these results, it appears that although feral swine can serve as a source of infection to humans, especially in those who are more likely to encounter them directly such as wildlife biologists, veterinarians, and hunters, the risk may be relatively low. However, further studies to examine the relationship between leptospiral shedding in the urine and kidneys in addition to culturing the organism are recommended in order to better understand the risk associated with feral swine.

  13. Discovery of 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-ones as a new class of pathogen specific anti-leptospiral agents.

    Science.gov (United States)

    Ilangovan, Andivelu; Sakthivel, Palaniappan; Sivasankari, Karikalacholan; Mercy, Charles Solomon Akino; Natarajaseenivasan, Kalimuthusamy

    2017-01-05

    A simple and efficient method for the synthesis of a series of 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-one derivatives starting from 5-carboalkoxy-2,3-dihydropyranone (5-CDHPs) has been developed. Pyranoisoxazolones 10a-j, dihydronaphthopyran-4-one (DHNPs) class of natural product 12b and 12c and its analogues 12a and 13a-c were preliminarily screened against pathogenic leptospiral serovar Autumnalis strain N2 at various concentrations. Six pyranoisoxazolones, 10b, 10d, 10f, 10g, 10i and 10j which displayed very good anti-leptospiral activity was taken for secondary screening against twelve strains of pathogenic and one non-pathogenic leptospiral serovars. While all the compounds displayed significant anti-leptospiral activity against the pathogenic serovars at MIC of 62.5-500 μg/mL. Compounds 10d, 10g and 10j did not show any significant effect on non-pathogenic serovar. Inhibition of leptospires at a significant level by pyranoisoxazolone 10g was confirmed using RT-qPCR assay. In vivo treatment of BALB/c mice with compound 10g revealed that, it has 95% survivability against the pathogenic strain Canicola and also showed inhibition of renal colonization of leptospires. Compound 10g was found to show cytotoxicity against THP-1 cells only at higher concentration (≥75 μg/mL). Effective binding of compound 10g with leptospiral outer membrane protein LipL32 observed via in silico molecular docking provided a suitable explanation for pathogen specificity of compound 10g. Antibiotics acting against leptospirosis in human are very few. The results obtained from in vitro, in vivo and in silico study reveals that 6,7-dihydro-3H-pyrano[4,3-c]isoxazol-3-ones class of compounds are lead molecules for further development as pathogen specific anti-leptospiral agents. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Role of intraocular Leptospira infections in the pathogenesis of Equine Recurrent Uveitis in the Southern United States

    Science.gov (United States)

    To investigate the role of intraocular leptospiral infections in horses with Equine Recurrent Uveitis (ERU) in the southern United States, blood and ocular fluid samples were collected from horses with a history and ocular findings consistent with ERU. Samples were also obtained from control horses ...

  15. 钩端螺旋体黄疸出血群赖株mviN基因的克隆%Cloning of mviN Gene of Leptospira Interrogans Serogroup Icterohaemorrhagiae Strain Lai

    Institute of Scientific and Technical Information of China (English)

    顾福萍; 蒋培余

    2008-01-01

    采用高保真PCR从我国钩体黄疸出血群赖株基因组中扩增全长mviN基因片段,对钩体黄疸出血群赖株mviN基因进行克隆.结果显示,所克隆的mviN基因的核苷酸和氨基酸序列与已发表的mviN基因序列(Accesion No.in GenBank: NC004343)同源性分别为99.68%和99.42%.因此可以认为,我们成功克隆了mviN基因,并为该基因的后续研究奠定了基础.

  16. Principais aspectos da infecção por Leptospira sp em ovinos Main aspects of Leptospira sp infection in sheep

    Directory of Open Access Journals (Sweden)

    Luiza de Souza Seixas Melo

    2010-05-01

    Full Text Available Este trabalho tem como objetivo revisar as infecções por Leptospira sp em ovinos. São abordados os aspectos epidemiológicos, incluindo a ocorrência no Brasil e as formas de transmissão, os sinais clínicos e as lesões, o diagnóstico e as medidas de prevenção e controle.An updated review of Leptopspira sp infection in sheep is presented emphasizing some epidemiological aspects including the occurrence of the disease in Brazil and mechanisms of transmission, clinical signs and lesions, diagnosis, prevention and control measures.

  17. Comparative genomic analysis of Brazilian Leptospira kirschneri serogroup Pomona serovar Mozdok

    Science.gov (United States)

    Moreno, Luisa Z; Kremer, Frederico S; Miraglia, Fabiana; Loureiro, Ana P; Eslabao, Marcus R; Dellagostin, Odir A; Lilenbaum, Walter; Moreno, Andrea M

    2016-01-01

    Leptospira kirschneri is one of the pathogenic species of the Leptospira genus. Human and animal infection from L. kirschneri gained further attention over the last few decades. Here we present the isolation and characterisation of Brazilian L. kirschneri serogroup Pomona serovar Mozdok strain M36/05 and the comparative genomic analysis with Brazilian human strain 61H. The M36/05 strain caused pulmonary hemorrhagic lesions in the hamster model, showing high virulence. The studied genomes presented high symmetrical identity and the in silico multilocus sequence typing analysis resulted in a new allelic profile (ST101) that so far has only been associated with the Brazilian L. kirschneri serogroup Pomona serovar Mozdok strains. Considering the environmental conditions and high genomic similarity observed between strains, we suggest the existence of a Brazilian L. kirschneri serogroup Pomona serovar Mozdok lineage that could represent a high public health risk; further studies are necessary to confirm the lineage significance and distribution. PMID:27581124

  18. Comparative genomic analysis of Brazilian Leptospira kirschneri serogroup Pomona serovar Mozdok

    Directory of Open Access Journals (Sweden)

    Luisa Z Moreno

    2016-08-01

    Full Text Available Leptospira kirschneri is one of the pathogenic species of the Leptospira genus. Human and animal infection from L. kirschneri gained further attention over the last few decades. Here we present the isolation and characterisation of Brazilian L. kirschneri serogroup Pomona serovar Mozdok strain M36/05 and the comparative genomic analysis with Brazilian human strain 61H. The M36/05 strain caused pulmonary hemorrhagic lesions in the hamster model, showing high virulence. The studied genomes presented high symmetrical identity and the in silico multilocus sequence typing analysis resulted in a new allelic profile (ST101 that so far has only been associated with the Brazilian L. kirschneri serogroup Pomona serovar Mozdok strains. Considering the environmental conditions and high genomic similarity observed between strains, we suggest the existence of a Brazilian L. kirschneri serogroup Pomona serovar Mozdok lineage that could represent a high public health risk; further studies are necessary to confirm the lineage significance and distribution.

  19. Orientia, rickettsia, and leptospira pathogens as causes of CNS infections in Laos

    DEFF Research Database (Denmark)

    Dittrich, Sabine; Rattanavong, Sayaphet; Lee, Sue J;

    2015-01-01

    BACKGROUND: Scrub typhus (caused by Orientia tsutsugamushi), murine typhus (caused by Rickettsia typhi), and leptospirosis are common causes of febrile illness in Asia; meningitis and meningoencephalitis are severe complications. However, scarce data exist for the burden of these pathogens......, Neisseria meningitidis, Haemophilus influenzae, S suis) and O tsutsugamushi, Rickettsia typhi/Rickettsia spp, and Leptospira spp infections in blood or cerebrospinal fluid (CSF). We analysed and compared causes and clinical and CSF characteristics between patient groups. FINDINGS: 1051 (95%) of 1112...... patients who presented had CSF available for analysis, of whom 254 (24%) had a CNS infection attributable to a bacterial or fungal pathogen. 90 (35%) of these 254 infections were caused by O tsutsugamushi, R typhi/Rickettsia spp, or Leptospira spp. These pathogens were significantly more frequent than...

  20. Prevalence of antibodies to Leptospira serovars in sheep and goats in Alto Adige-South Tyrol.

    Science.gov (United States)

    Ciceroni, L; Lombardo, D; Pinto, A; Ciarrocchi, S; Simeoni, J

    2000-04-01

    Serum samples from 313 sheep and 95 goats were collected during November 1993 in 26 localities in Alto Adige-South Tyrol and tested by microscopic agglutination test for antibodies to 28 serovars of the genus Leptospira. At the time of blood collection all the animals appeared healthy with no clinical sign suggestive of leptospirosis. The observed seroprevalence in sheep was 6.1%, whereas the seropositivity rate for goat serum samples was 2.1%. The highest serological prevalence in sheep was recorded for serovar castellonis, followed by poi, sejroe, hardjo subtype hardjobovis, copenhageni, and cynopteri. Titres to poi were the only ones found in goats. These findings, which are proof of Leptospira infection in Alto Adige-South Tyrol, indicate that foci of several serovars exist in this region.

  1. [Construction of genomic library of L. interrogans serovar lai using lambda gt11 as the vector and a study of recombiant plasmid pDL121].

    Science.gov (United States)

    Liu, H; Dai, B; Jing, B; Wu, W; Li, S; Fang, Z; Zhao, H; Ye, D; Yan, R; Liu, J; Song, S; Yang, Y; Zhang, Y; Liu, F; Tu, Y; Yang, H; Huang, Z; Liang, L; Hu, L; Zhao, M

    1997-03-01

    A genomic library of L. interrogans serovar lai strain 017 has been constructed using lambda gt11 as the vector. DNA was partially digested by two blunt-end restriction enzymes, then methylated with EcoR I methylase; after EcoR I linker was added to the DNA, the linker-ended DNA was ligated to the dephosphorylated EcoR I digested lambda gt11 arms. The recombined DNA was packaged in vitro, and used to transduct E. coli Y1090 for amplification. There were 2.1 x 10(6) recombinant bacteriophages as recognized by their ability to form white plaques plated on Lac host in the presence of both IPTG and X-Ga1. A positive clone, designated lambda DL12, was screened with a rabbit anti-serum against L. interrogans serovar lai from the genomic library. The DNA from lambda DL12 was subcloned into plasmid pUC18. A recombinant (designated as pDL121) was obtained. SDS-PAGE analysis indicated that a 23 kd was expressed in E. coli JM 103 harboring pDL121. Western blotting analysis showed that a specific protein band molecular weight of 23 kd could be recognized by the rabbit antiserum against L. interrogans serovar lai strain 017.

  2. Principais aspectos da infecção por Leptospira sp em ovinos

    OpenAIRE

    Melo, Luiza de Souza Seixas; de Castro, Márcio Botelho; Leite,Rômulo Cerqueira; Moreira, Élvio Carlos; Melo, Cristiano Barros de

    2010-01-01

    Este trabalho tem como objetivo revisar as infecções por Leptospira sp em ovinos. São abordados os aspectos epidemiológicos, incluindo a ocorrência no Brasil e as formas de transmissão, os sinais clínicos e as lesões, o diagnóstico e as medidas de prevenção e controle.

  3. Enhancement of Leptospira hardjo agglutination titers in sheep and goat serum by heat inactivation.

    Science.gov (United States)

    Malkin, K

    1984-04-01

    Heat inactivation of sheep serum samples resulted in the detection of an additional 9% reactors to Leptospira hardjo that were negative on the initial test of fresh samples. Treatment with EDTA gave results generally similar to heat inactivation suggesting that complement was responsible for the inhibition of agglutination. Tests on heat inactivated serum from experimentally infected sheep and goats revealed enhanced titers or reactions which were not detected in fresh serum.

  4. [Sensitivity of different morphological variants of Leptospira to the leptospirocidal activity of normal animal sera].

    Science.gov (United States)

    Anan'ina, Iu V; Chernukha, Iu G

    1984-10-01

    The leptospirocidal activity of normal animal sera with respect to 23 Leptospira strains was experimentally studied in vitro. 91.3% of the strains under study proved to be sensitive to the lytic action of cattle serum and 86.9%, to sheep serum. The uncinate variants of the pathogenic strains showed resistance to the action of the above sera, and their nonuncinate analogs were subject to agglutination with subsequent lysis, similarly to saprophytes.

  5. Detecção molecular de ovinos carreadores de Leptospira em ambiente tropical

    Directory of Open Access Journals (Sweden)

    Ariel Director

    2014-12-01

    Full Text Available O objetivo do presente estudo foi analisar a aplicabilidade da PCR na detecção de ovinos carreadores de Leptospira em ambiente tropical. Brevemente, dois rebanhos ovinos, previamente reportados como sororeativo (A e soronegativo (B foram selecionados para este estudo. Da totalidade de animais de cada rebanho, amostras de urina e fluido vaginal (FV/sêmen foram colhidas para cultura bacteriológica e PCR. Além disso, amostras de soro foram colhidas e utilizadas na sorologia (teste da soroaglutinação microscópica. Esta técnica confirmou o estado prévio dos dois rebanhos. Nenhuma amostra pura de leptospiras foi obtida no cultivo. Já na PCR, animais do Rebanho A apresentaram 26,7% (FV, 33,3% (sêmen e 38,9% (urina de amostras positivas. O Rebanho B apresentou 40,0% (FV, 33,3% (sêmen e 5,6% (urina de positividade pela PCR. Em conclusão, a PCR foi uma importante ferramenta na identificação de carreadores de leptospiras, incluindo animais do rebanho soronegativo, o que reforça as vantagens do uso desta técnica para a detecção de ovinos portadores como parte dos programas de controle da leptospirose em ambiente tropical.

  6. Isolation of Leptospira spp from dogs, bovine and swine naturally infected

    Directory of Open Access Journals (Sweden)

    Freitas Julio Cesar de

    2004-01-01

    Full Text Available Leptospira isolation allows definitive diagnosis of the infection. Contamination by microorganisms is one of the inconveniences of the culture. The objective of this study was to describe the isolation of Leptospira from dogs, bovine and swine naturally infected. Urine samples from 14 dogs and three bovines, and kidney, liver, ovary, and uterus body samples from 36 slaughtered sows with unknown health history, were used. The urine and organ samples were cultured in culture medium. Modified Ellinghausen-McCullough-Johnson-Harris medium (EMJH culture medium was used with addition of 5-fluorouracil, chloramphenicol, vancomycin, nalidixic acid and neomycin. Incubation was performed at 28oC for 24 hours, followed by subculture in modified EMJH without antibiotics. The cultures were assessed weekly for up to eight weeks for the dog and swine samples and for up to 16 weeks for the bovine samples. With this methodology, Leptospira spp could be isolated from 11 dogs, two bovines and liver fragments from two sows.

  7. Leptospira spp. infection in wild ruminants: a survey in Central Italian Alps

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    Elena Andreoli

    2014-12-01

    Full Text Available Leptospirosis is an important zoonotic disease diffused worldwide, and wildlife species are commonly considered to be important epidemiological carriers. Four-hundred and forty‑one serological and 198 renal samples from red deer, roe deer and chamois collected in the Province of Sondrio were analysed using the microscopic agglutination test and histopathologic examination. Positive serological findings were found only in 15 red deer and 19 positive serologic reactions were recorded. The most frequent serovars were Bratislava and Grippotyphosa, followed by Pomona, Hardjo and Copenhagheni. Twenty-two per cent of renal samples from seropositive red deer were affected by mild to moderate multifocal chronic lymphoplasmacytic and fibrosing tubulo-interstitial nephritis, mainly involving the cortical parenchyma. In this study, antibodies to Leptospira spp. were infrequent in wild ruminants, and only red deer seemed to be sensitive to the infection. Given the low presence and the fact that there was no record of Leptospira spp. infections in cattle, sheep, goats and also hunters in area during the study period, wild ruminants in Alpine environments cannot be considered as reservoirs or important sources of Leptospira spp. infection for humans or domestic animals.

  8. Frequency of Leptospira spp. in sheep from Brazilian slaughterhouses and its association with epidemiological variables

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    Rodrigo Costa da Silva

    2012-03-01

    Full Text Available Leptospirosis is a worldwide anthropozoonosis that infects livestock, including sheep as the carriers to other animals and humans. The present study aimed to determine the prevalence of Leptospira spp. in sheep from two slaughterhouses in the state of São Paulo, Brazil and its association with epidemiological variables. Serum samples from 182 sheep were evaluated for Leptospira spp. antibodies by microscopic agglutination test (MAT. Results indicated 34/182 (18.68%; CI95% 13.70-24.98% positive serum samples, mainly to the serovar Copenhageni (17/34; 50%; CI95% 33.99-66.01%. Bacterial growth in the Fletcher medium was detected for 13/34 (38.24%; CI95% 23.87-55.08% animals, and confirmed by Polymerase Chain Reaction (PCR and sequencing for only two kidney samples from two animals. Thus, treatment and vaccination of sheep, besides rodent control, can be useful to prevent the infection in the studied region since sheep are important Leptospira spp. carriers, and its transmission to slaughterhouse workers is mainly through the manipulation of visceral tissues.

  9. Leptospira spp. infection in wild ruminants: a survey in Central Italian Alps.

    Science.gov (United States)

    Andreoli, Elena; Radaelli, Enrico; Bertoletti, Irene; Bianchi, Alessandro; Scanziani, Eugenio; Tagliabue, Silvia; Mattiello, Silvana

    2014-12-29

    Leptospirosis is an important zoonotic disease diffused worldwide, and wildlife species are commonly considered to be important epidemiological carriers. Four-hundred and forty-one serological and 198 renal samples from red deer, roe deer and chamois collected in the Province of Sondrio were analysed using the microscopic agglutination test and histopathologic examination. Positive serological findings were found only in 15 red deer and 19 positive serologic reactions were recorded. The most frequent serovars were Bratislava and Grippotyphosa, followed by Pomona, Hardjo and Copenhagheni. Twenty-two per cent of renal samples from seropositive red deer were affected by mild to moderate multifocal chronic lymphoplasmacytic and fibrosing tubulo-interstitial nephritis, mainly involving the cortical parenchyma. In this study, antibodies to Leptospira spp. were infrequent in wild ruminants, and only red deer seemed to be sensitive to the infection. Given the low presence and the fact that there was no record of Leptospira spp. infections in cattle, sheep, goats and also hunters in area during the study period, wild ruminants in Alpine environments cannot be considered as reservoirs or important sources of Leptospira spp. infection for humans or domestic animals.

  10. Detection of pathogenic Leptospira from selected environment in Kelantan and Terengganu, Malaysia.

    Science.gov (United States)

    Ridzlan, F R; Bahaman, A R; Khairani-Bejo, S; Mutalib, A R

    2010-12-01

    Leptospirosis is recognized as one of the important zoonotic diseases in the world including Malaysia. A total of 145 soil and water samples were collected from selected National Service Training Centres (NSTC) in Kelantan and Terengganu. The samples were inoculated into modified semisolid Ellinghausen McCullough Johnson Harris (EMJH) medium, incubated at room temperature for 1 month and examined under the dark-field microscope. Positive growth of the leptospiral isolates were then confirmed with 8-Azaguanine Test, Polymerase Chain Reaction (PCR) assay and Microscopic Agglutination Test (MAT). Fifteen cultures (10.34%) exhibited positive growths which were seen under dark field microscope whilst only 20% (3/15) were confirmed as pathogenic species. based on 8-Azaguanine Test and PCR. Serological identification of the isolates with MAT showed that hebdomadis was the dominant serovar in Terengganu. Pathogenic leptospires can be detected in Malaysian environment and this has the potential to cause an outbreak. Therefore, precautionary steps against leptospirosis should be taken by camp authorities to ensure the safety of trainees.

  11. Dicty_cDB: Contig-U05833-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available AE016823_748( AE016823 |pid:none) Leptospira interrogans serovar C... 34 6.1 FJ196874_2( FJ196874 |pid:none) Gallus gallus microphth...almia-assoc... 34 6.1 AE010300_3398( AE010300 |pid:none) Leptospira interrogans ser

  12. Contrasting patterns in mammal-bacteria coevolution: bartonella and leptospira in bats and rodents.

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    Bonnie R Lei

    2014-03-01

    Full Text Available BACKGROUND: Emerging bacterial zoonoses in bats and rodents remain relatively understudied. We conduct the first comparative host-pathogen coevolutionary analyses of bacterial pathogens in these hosts, using Bartonella spp. and Leptospira spp. as a model. METHODOLOGY/PRINCIPAL FINDINGS: We used published genetic data for 51 Bartonella genotypes from 24 bat species, 129 Bartonella from 38 rodents, and 26 Leptospira from 20 bats. We generated maximum likelihood and Bayesian phylogenies for hosts and bacteria, and tested for coevoutionary congruence using programs ParaFit, PACO, and Jane. Bartonella spp. and their bat hosts had a significant coevolutionary fit (ParaFitGlobal = 1.9703, P≤0.001; m2 global value = 7.3320, P≤0.0001. Bartonella spp. and rodent hosts also indicated strong overall patterns of cospeciation (ParaFitGlobal = 102.4409, P≤0.001; m2 global value = 86.532, P≤0.0001. In contrast, we were unable to reject independence of speciation events in Leptospira and bats (ParaFitGlobal = 0.0042, P = 0.84; m2 global value = 4.6310, P = 0.5629. Separate analyses of New World and Old World data subsets yielded results congruent with analysis from entire datasets. We also conducted event-based cophylogeny analyses to reconstruct likely evolutionary histories for each group of pathogens and hosts. Leptospira and bats had the greatest number of host switches per parasite (0.731, while Bartonella and rodents had the fewest (0.264. CONCLUSIONS/SIGNIFICANCE: In both bat and rodent hosts, Bartonella exhibits significant coevolution with minimal host switching, while Leptospira in bats lacks evolutionary congruence with its host and has high number of host switches. Reasons underlying these variable coevolutionary patterns in host range are likely due to differences in disease-specific transmission and host ecology. Understanding the coevolutionary patterns and frequency of host-switching events between

  13. Frequency and type of renal lesions in dogs naturally infected with leptospira species.

    Science.gov (United States)

    Ortega-Pacheco, A; Colin-Flores, R F; Gutiérrez-Blanco, E; Jiménez-Coello, M

    2008-12-01

    The aim of this study was to determine the frequency and type of renal lesions associated with positive titers against Leptospira sp. in a stray dog population. Three hundred fifty pairs of kidneys and an equal number of serum samples were collected from dogs captured by the dog pound of Merida, Yucatan, Mexico. Euthanasia of dogs was performed following the regulations of the Official Mexican Health Ministry (NOM-033-ZOO-1995). Serum samples were evaluated with the microscopic agglutination test, and tissue samples were processed and fixed in paraffin. After staining with hematoxylin and eosin, the frequency of renal lesions was determined and classified. As an additional evaluation, samples with interstitial nephritis were stained by the Warthin-Starry method in order to observe the presence of spirochete forms that could be morphologically compatible with Leptospira spp. We found that 98% of cases presented at least one type of lesion. The main histological lesions found were mesangial proliferative glomerulonephritis (MPGN) in 63.7% (n= 223), mesangial proliferative glomerulonephritis and interstitial nephritis (MPGN+IN) in 34% (n= 119), nephrosclerosis in 0.57% (n= 2), mesangial glomerulonephritis in 0.28% (n= 1), and interstitial nephritis (IN) in 0.28% (n= 1). Thirty-four percent (n= 122) of the dogs were seropositive to Leptospira sp., mainly against serovar canicola. Among dogs with IN (alone or associated with MPGN) (n= 120), 49.1% were seropositive to Leptospira sp., but only 17% of them showed spirochete forms compatible with the bacteria. A statistical association between seropositive dogs and the presence of MPGN+IN was determined (P < 0.0001; odds ratio 2.7, confidence interval 1.7-4.5). We concluded that the frequency of renal lesions found in this study is high and L. canicola is probably the most common circulating serovar in dogs from this area. Dogs that have been in contact with Leptospira spp. have a higher risk of developing renal lesions of

  14. Serological investigation of Leptospira infection and its circulation in one intensive-type water buffalo farm in the Philippines.

    Science.gov (United States)

    Villanueva, Marvin A; Mingala, Claro N; Gloriani, Nina G; Yanagihara, Yasutake; Isoda, Norikazu; Nakajima, Chie; Suzuki, Yasuhiko; Koizumi, Nobuo

    2016-02-01

    Water buffalo is an indispensable livestock in the Philippines. Leptospirosis is a serious zoonosis that can be fatal to humans and cause reproductive problems in livestock. Leptospirosis has been reported in some countries where water buffaloes are commercially raised, highlighting the Leptospira prevalence in this farming system, but information on leptospirosis in water buffalo farms in the Philippines is limited. In this study, we collected blood samples from rats (n = 21), and water buffaloes (n = 170) from different groups and locations in one intensive-type buffalo farm in the Philippines. Serum was analyzed by microscopic agglutination test (MAT). Anti-Leptospira antibodies reacting with serogroups Canicola, Icterohaemorrhagiae and Pomona were found in sera of 30% tested rats, and 48% of water buffalo sera tested positive for at least one Leptospira strain, in which serogroups Mini, Hebdomadis, Tarassovi and Pyrogenes were predominantly agglutinated. The number of seropositive young water buffaloes (animals were reactive with multiple Leptospira strains with variable MAT titers. In addition, antibodies against serogroups Icterohaemorrhagiae and Pomona were detected in both animals. Finally, Leptospira infection was found associated with age and animal grouping, highlighting the impact of management in the persistence of leptospirosis at intensive-type buffalo farm settings in the Philippines. Further investigation and appropriate control strategies are required to prevent leptospirosis from causing risks to public health and economic losses to the water buffalo farming industry.

  15. [Intraocular and serum antibody titers to Leptospira in 150 horses with equine recurrent uveitis (ERU) subjected to vitrectomy].

    Science.gov (United States)

    Wollanke, B; Gerhards, H; Brem, S; Kopp, H; Meyer, P

    1998-04-01

    Between February 1993 and July 1997, 150 horses suffering from recurrent uveitis were subjected to parsplana vitrectomy. In these horses, antibody titers to Leptospira serovars were determined in serum samples and in samples from diluted vitreous collected during vitrectomy. Although the vitreous samples were diluted with 250 ml of balanced salt solution, in 86 of the 150 vitreous samples (= 57%) the antibody titers were higher than in the serum samples. Additionally, serum samples from 77 horses suffering from ERU, but which were not subjected to vitrectomy, and serum samples from 97 horses with clinically normal eyes were analyzed for antibodies to Leptospira serovars. Among the 227 horses with ERU (150 treated surgically, 77 treated conservatively) 50 horses (50 of 227 = 22%) had serum antibody titers to Leptospira serovars of > or = 1:800. Among the 97 horses with clinically normal eyes, 24 horses (24 of 97 = 25%) had serum antibody titers to Leptospira serovars of > or = 1:800. In undiluted vitreous samples from 20 horses with clinically normal eyes, no antibody titers to Leptospira serovars could be detected. Among the 150 horses with ERU, 90 animals (90 of 150 = 60%) had antibody titers of > or = 1:100 in the diluted vitreous samples, the difference being highly significant (p < 0.001). The findings are discussed in relation to the etiology of recurrent uveitis in horses.

  16. Carrier status of leptospirosis among cattle in Sri Lanka: a zoonotic threat to public health.

    Science.gov (United States)

    Gamage, C D; Koizumi, N; Perera, A K C; Muto, M; Nwafor-Okoli, C; Ranasinghe, S; Kularatne, S A M; Rajapakse, R P V J; Kanda, K; Lee, R B; Obayashi, Y; Ohnishi, M; Tamashiro, H

    2014-02-01

    Leptospirosis is a zoonotic disease of global importance and one of the notifiable diseases in Sri Lanka. Recent studies on human leptospirosis have suggested that the cattle could be one of the important reservoirs for human infection in the country. However, there is a dearth of local information on bovine leptospirosis, including its implications for human transmission. Thus, this study attempted to determine the carrier status of pathogenic Leptospira spp in cattle in Sri Lanka. A total of 164 cattle kidney samples were collected from the meat inspection hall in Colombo city during routine inspection procedures conducted by the municipal veterinary surgeons. The DNA was extracted and subjected to nested PCR for the detection of leptospiral flaB gene. Amplicons were sequenced, and phylogenic distances were calculated. Of 164 samples, 20 (12.2%) were positive for flaB-PCR. Sequenced amplicons revealed that Leptospira species were deduced to L. borgpetersenii (10/20, 50%), L. kirschneri (7/20, 35%) and L. interrogans (3/20, 15%). The results indicate that a high proportion of the sampled cattle harbour a variety of pathogenic Leptospira spp, which can serve as important reservoirs for human disease.

  17. [Detection of leptospira in the vitreous body of horses without ocular diseases and of horses with equine recurrent uveitis (ERU) using transmission-electron microscopy].

    Science.gov (United States)

    Niedermaier, G; Wollanke, B; Hoffmann, R; Brem, S; Gerhards, H

    2006-11-01

    Equine recurrent uveitis (ERU) is caused by persistent intraocular leptospira, which appear to use the vitreous body as a refuge. The detection of leptospira in the vitreous body of horses with spontaneous ERU by histological methods has not yet been described. Thirty eight vitreous body samples from 36 horses with ERU (collected during vitrectomy), and 10 vitreous body samples obtained from 5 horses without ocular disease (control group) were examined by transmission electron microscopy. Prior to sample collection, 2 ml of a leptospira culture suspension were injected into the vitreous body of 2 eyes enucleated from horses of the control group. The detection of leptospira in samples, experimentally inoculated with these bacteria was uncomplicated; in vitreous body samples from horses with spontaneous ERU the detection was successful in only a few cases (3/38). The morphologically varying envelope of leptospira in vitreous body samples of horses which developed ERU spontaneously suggests the existence of a bacterial masquerade in vivo.

  18. A novel pore-forming hemolysin protein in Leptospira species%LA0202为钩端螺旋体中一孔形成溶血素蛋白

    Institute of Scientific and Technical Information of China (English)

    杨杨; 秦金红; 钟怡; 何平; 胡宝瑜; 郭晓奎

    2009-01-01

    目的 研究LA0202为孔形成溶血素.方法 体外克隆表达LA0202蛋白.纯化的LA0202蛋白作用绵羊血细胞观察LA0202的溶血活性并用渗透压保护剂PEG6000添加到作用体系研究渗透压保护剂对LA0202溶血活性的影响.透射电镜及扫描电镜观察LA0202作用于体外培养的肝细胞后对细胞的毒性.结果 渗透压保护剂PEG6000能够抑制LA0202的溶血活性.LA0202作用于肝细胞后引起肝细胞的毒性损伤.结论 LA0202为一孔形成溶血素.%Hemolysins of Leptospira interragans have been shown to be the virulence factor in the pathogenesis of leptospirosis and 10 potential hemolysin genes were charecterized by genomic annotation of L.interrogans serovar.Lai strain 56601. In the present study, the LA0202 gene supposed to encode one of the new potential hemolysin was cloned and the protein encoded was purified. The purified protein was shown to have highly hemolytic activity as demonstrated on the sheep blood agar plate. It was also confirmed that the LA0202 protein-mediated hemolysis on sheep erythrocytes was osmotically protected by PEG6000. Meanwhile, this protein could induce pore formation on sheep erythrocytes and cause damages on the membrane of human L-02 liver cells. In addition, it could induce apoptosis of human L-02 liver cells after treatment of cells with this protein for 24 hours. It is evident that LA0202 protein acting as a pore-formong hemolysin can induce cytotoxic damage on mammalian cells.

  19. Prevalência de anticorpos anti-Neospora caninum, anti toxoplasma gondii e anti-leptospira spp. e resposta vacinal para Leptospira spp. em rebanho ovino no município de Uberlândia, MG

    OpenAIRE

    Moreira, Rafael Quirino

    2009-01-01

    Os objetivos do presente trabalho foram: verificar a soroprevalência de Neospora caninum, Toxoplasma gondii e Leptospira spp; monitorar a prevalência para Leptospira spp. num intervalo de 10 meses; e aferir o perfil de aglutininas induzido pela soroconversão de duas bacterinas polivalentes em rebanho ovino com relatos contra perdas reprodutivas no município de Uberlândia, MG. Foram colhidas amostras de sangue de 98 ovinos. As amostras foram testadas frente ao ELISA para Neospor...

  20. Duration of immunity of a multivalent (DHPPi/L4R) canine vaccine against four Leptospira serovars.

    Science.gov (United States)

    Wilson, Stephen; Stirling, Catrina; Thomas, Anne; King, Vickie; Plevová, Edita; Chromá, Ludmila; Siedek, Elisabeth; Illambas, Joanna; Salt, Jeremy; Sture, Gordon

    2013-06-28

    Despite effective vaccines against common Leptospira serovars, the development of new products with long duration of immunity is still important to protect dogs against leptospirosis. The results from four challenge studies performed one year after vaccination of dogs with a multivalent vaccine containing four Leptospira antigens are reported. Six week old dogs received two vaccinations, three weeks apart, and were challenged 367 days later. Clinical observations were recorded, while blood (culture, biochemistry and haematology), urine (culture) and liver and kidney (culture) samples were collected throughout the study or at necropsy. All control dogs remained seronegative until challenge, when they seroconverted. Antibody titres to Leptospira antigens were seen in vaccinated dogs 21 days after first vaccination and peaked three to six weeks after the second vaccination. Titres decreased in all studies over the following 12 months, until challenge when anamnestic responses were observed. In all studies control dogs demonstrated various abnormal clinical signs, while no vaccinated dogs were affected; differences between groups were only significant following L. bratislava challenge. Analysis of blood cultures showed all control and five of the 24 vaccinated dogs were Leptospira positive after challenge; all studies showed significant differences between treatment groups in mean number of days with positive cultures. Significant differences between vaccinated and control groups in mean number of days with positive urine cultures were also observed, with all non-vaccinated and one vaccinated dog Leptospira positive. The urine culture positive vaccinated dog also gave positive culture from kidney and liver samples. All except one control dog also showed positive Leptospira isolation from kidney or liver, with significant differences between vaccinated and control groups observed. The results demonstrate that administration of a new vaccine to six week old puppies

  1. Seroprevalence and Risk Factors for Leptospira Seropositivity in Beef Cattle, Sheep and Deer Farmers in New Zealand.

    Science.gov (United States)

    Sanhueza, J M; Heuer, C; Wilson, P R; Benschop, J; Collins-Emerson, J M

    2016-12-05

    Leptospirosis is a global zoonosis that in New Zealand affects primarily people occupationally exposed to livestock. The objective of this study was to estimate the seroprevalence of five Leptospira serovars in farmers working on cattle, sheep and deer farms that had the serological status of animals previously assessed and to identify risk factors for farmer seropositivity. A total of 178 farmers from 127 properties participated in the study. Blood samples were tested using the microscopic agglutination test (MAT) for the presence of antibodies to Leptospira. Samples with a MAT titre ≥48 were considered seropositive. Using Bayesian statistical analysis, the median seroprevalence of Leptospira, all serovars combined, was estimated to be 6.6% (95% probability interval (PI) 3.6-10.9%). Risk factors associated with seropositivity were assisting deer or cattle calving, farming deer, having ≥25% of flat terrain and high abundance of wild deer on farm, while high possum abundance on farm was negatively associated with seropositivity. No association was observed between farmer serostatus and previously recorded livestock serology. Leptospira seropositivity was associated with influenza-like illness of farmers (RR = 1.7; 95% PI 1.0-2.5). Assuming a causal relationship, this suggested an annual risk of 1.3% (95% PI 0.0-3.0%) of influenza-like illnesses due to Leptospira infection in the population of farmers. The association between seropositivity and disease can be used to estimate the public health burden of leptospirosis in New Zealand. Identifying and understanding risk factors for Leptospira seropositivity can inform preventive measures, hence contributing to the reduction of leptospirosis incidence in farmers.

  2. Prevalence and risk factors for Leptospira spp. in cattle herds in the south central region of Paraná state

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    Vanessa Y Hashimoto

    2012-02-01

    Full Text Available The aim of this study was to determine the prevalence of anti-Leptospira spp. antibodies and the risk factors for Leptospira spp. infection in breeding cattle herds in the south central region of Paraná state. It was based on the statistic delineation/serological samples and information regarding the selected farms employed in the study of bovine brucellosis for Paraná state in the context of National Program for Control and Eradication of Brucellosis and Tuberculosis. A total of 1.880 females aged >24 months from 274 non vaccinated herds were studied. Serum samples were tested for antibodies against Leptospira spp. using microscopic agglutination test (MAT with 22 Leptospira serovars. The epidemiological questionnaire was applied on all the selected farms and aimed to obtain epidemiological data. Hundred eighty one of 274 herds were positive for Leptospira spp./presenting prevalence of positive herds of 66.06% (IC95%=60.12-71,65%. Presence of >43 cattle (OR=3.120; IC=1.418-6.867/animal purchase (OR=2.010; IC=1.154-3.500/rent of pastures (OR=2.925; IC=1.060-8.068 and presence of maternity paddock (OR=1.981; IC=1,068-3,676 were identified as risk factors for leptospirosis due to any serovar in the multivariate logistic regression. Risk factors for leptospirosis due to serovar Hardjo were presence of >43 cattle (OR=3.622; IC=1.512-8,677/animal purchase (OR=3.143; IC=1.557-6.342/rent of pastures (OR=4.070; IC=1.370-12.087 and presence of horses (OR=2.981; IC=1.321-6.726. These results indicate that Leptospira spp. infection is widespread in the south central region of Paraná state and that factors related to the herd characteristic and management are associated with the infection.

  3. Frequência de anticorpos contra Leptospira spp. e Trypanosoma cruzy em primatas neotropicais mantidos em cativeiro

    OpenAIRE

    2010-01-01

    Faz um levantamento sorológico para anticorpos contra Leptospira spp e Trypanosoma cruzi em primatas neotropicais mantidos em cativeiro. Amostras de 94 primatas neotropicais adultos, machos e fêmeas de diferentes espécies pertencentes ao criatório do Centro Nacional de Primatas (CENP)-Ananindeua-PA, coletadas para a realização da Soroaglutinação Microscópica (SAM), na qual foram utilizadas 84 amostras sorológicas, em que 35 (41,67%) apresentaram anticorpos contra leptospira e 49 (58,...

  4. Emergency caesarean delivery in a patient with cerebral malaria-leptospira co infection: Anaesthetic and critical care considerations

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    Sukhen Samanta

    2014-01-01

    Full Text Available Malaria-leptospira co-infection is rarely detected. Emergency surgery in such patients has not been reported. We describe such a case of a 24-year-old primigravida at term pregnancy posted for emergency caesarean delivery who developed pulmonary haemorrhage, acute respiratory distress syndrome, acute kidney injury, and cerebral oedema. Here, we discuss the perioperative management, pain management (with transverse abdominis plane block, intensive care management (special reference to management of pulmonary haemorrhage with intra pulmonary factor VIIa and the role of plasmapheresis in leptospira related jaundice with renal failure.

  5. New approach for serological testing for leptospirosis by using detection of leptospira agglutination by flow cytometry light scatter analysis.

    Science.gov (United States)

    Yitzhaki, S; Barnea, A; Keysary, A; Zahavy, E

    2004-04-01

    Leptospirosis is considered an important reemerging infectious disease worldwide. The standard and most widespread method for the diagnosis of leptospirosis is the microscopic agglutination test (MAT). This test is laborious and time-consuming, and the interpretation of the results is subjective. In the present work we describe an application of flow cytometry (FCM) as a tool for the serological diagnosis of leptospirosis. The analysis is based on the sensitivity of FCM to the size and shape of the bacteria analyzed by measurement of light scatter parameters: forward scatter (FSC) and side scatter (SSC). The addition of positive serum to an infecting leptospiral serovar results in a shift of the light scatter parameter to a different location with higher FSC and SSC values, indicating the formation of leptospiral aggregates. By using immunofluorescent staining, we have shown that the large particles formed are the agglutinated leptospires. Quantification of the agglutination process has been achieved by calculating an agglutination factor (Af), based on changes in the light scatter parameters measured by FCM. Af enables us to determine the specificity of the serological reaction of the patient serum with each leptospiral serovar. In this work, 27 serum samples from 18 leptospirosis patients were tested by both the MAT and the FCM techniques, in which each serum sample was tested against 13 serovars. Twenty-six human serum samples derived from patients with a variety of other defined illnesses were used as negative controls and enabled us to define the Af threshold value as < 9.3 for negative patients, while any value higher than that would be a positive result for leptospirosis. Compared to MAT, the FCM technique was found to be more specific and sensitive, especially in identifying the serogroup in the acute phase of the disease. The whole process was found to be rapid and took less than 1.5 h. Moreover, FCM analysis is objective and can be automated for the

  6. Establishment of a leptospirosis model in guinea pigs using an epicutaneous inoculations route

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    Zhang Yan

    2012-01-01

    Full Text Available Abstract Background Leptospires are presumed to enter their host via small abrasions or breaches of the skin. The intraperitoneal route, although commonly used in guinea pig and hamster models of leptospirosis, does not reflect conditions encountered during natural infection. The aim of this study is to develop a novel leptospirosis guinea pig model through epicutaneous route and to elucidate the pathogenesis of leptospirosis in experimental guinea pigs by comparing the data from other studies using different infection routes. Methods The guinea pigs were inoculated with 5 × 108 Leptospira interrogans strain Lai onto either shaved-only or abraded skin. The guinea pigs were sacrificed at 2, 8, 24, 48, 72, 96 and 144 h post-infection (p.i. followed by harvest of the lungs, liver, kidneys, spleen, and the skin around the inoculated sites for further examinations. Hematoxylin and eosin (HE staining and electron microscopy were used to detect the pathologic changes. Real time PCR and immunohistochemistry staining were performed to detect dynamic distribution of leptospires in blood and tissues, respectively. Results In the guinea pigs with abraded skin inoculations, leptospires were detected in blood as early as 2 h post infection (p.i. and then disseminated to the liver, lungs and kidneys of almost all animals within 96 h p.i.. Leptospires were also detected engulfed in the swelling vascular endothelial cells and were frequently aggregated around the capillaries in the dermis and subcutaneous tissue under the inoculated site. For the guinea pigs with abraded skin inoculations, hemorrhage at the dermis around the inoculated site was found before the appearance of internal organs hemorrhage, severe lesions such as hemorrhages in the lungs, nephritis, jaundice, haematuria were also observed, and two of seven guinea pigs died at 144 h p.i. while no lesions and leptospires were detected in the shaved-only guinea pigs using the same dose of strain Lai

  7. Preliminary serological study of Leptospira spp. in a sheep flock on the savannah of Bogotá

    Directory of Open Access Journals (Sweden)

    Jessica Alexandra Parra Solano

    2016-06-01

    Full Text Available The research aimed to conduct a serological study on leptospirosis in a sheep flock on the savannah of Bogotá, in order to detect the presence of this agent and to broaden knowledge on its tendency in our field. There were two visits to the farm, one during the dry season ( January and another one in the rainy season (May, to check 250 animals in each season, which were 100 males and 150 females of different races living on the farm. Microscopic agglutination test was used to determine the presence of antibodies to the six serovars that have been identified as the most frequent in Colombia in different domestic species. The results of the study indicated that the most common serovar in sheep was L. interrogans serovar Icterohaemorrhagiae, followed by L. interrogans serovar Bratislava, L. borgpetersenii serovar Hardjo, L. interrogans serovars Canicola, Pomona and Grippotyphosa. The research concluded that, even though there were no clinical cases reported during the study, leptospirosis associated with different serovars in sheep suggests the presence of the agent in the herd; new studies would be necessary to deepen our knowledge on the effect this would have on reproduction.

  8. Aspectos moleculares relevantes de las proteínas de patogenicidad de Leptospira sp.

    OpenAIRE

    2010-01-01

    La leptospirosis es una zoonosis ampliamente difundida, que afecta cerca de 160 especies salvajes y domésticas, las cuales se constituyen en reservorios latentes y son fuente primaria de contaminación para el hombre. Esta zoonosis es causada por la Leptospira sp., bacteria Gram negativa que tiene la capacidad de sobrevivir en la orina. Esto, sumado a la presencia de charcos, lagunas y aguas estancadas que se contaminan fácilmente y se convierten en un foco permanente de transmisión, hace de l...

  9. Prevalence of leptospira species among farmed and domestic animals in Greece.

    Science.gov (United States)

    Burriel, A R; Dalley, C; Woodward, M J

    2003-08-02

    A total of 1527 serum samples from pigs, goats, sheep, cattle and dogs in Greece were examined by the microscopic agglutination test and 11-8 per cent of them had antibodies against one or more Leptospira serovars at titres of 1/100 or more. The predominant serovar affecting farm animal species was Bratislava, and Copenhageni was common among dogs and the second most important serovar when all animals were considered together. Another prevalent serovar was Australis, but antibodies to Pomona were detected only in goats and cattle.

  10. A comparison of two real-time polymerase chain reaction assays using hybridization probes targeting either 16S ribosomal RNA or a subsurface lipoprotein gene for detecting leptospires in canine urine.

    Science.gov (United States)

    Gentilini, Fabio; Zanoni, Renato Giulio; Zambon, Elisa; Turba, Maria Elena

    2015-11-01

    Leptospires are excreted in the urine of infected animals, and the prompt detection of leptospiral DNA using polymerase chain reaction (PCR) is increasingly being used. However, contradictory data has emerged concerning the diagnostic accuracy of the most popular PCR assays that target either the 16S ribosomal RNA (rrs) or the subsurface lipoprotein (LipL32) genes. In order to clarify the effect of the gene target, a novel hydrolysis probe-based, quantitative real-time PCR (qPCR) assay targeting the LipL32 gene was developed, validated, and then compared directly to the previously described rrs hydrolysis probe-based qPCR using a convenience collection of canine urine samples. The novel LipL32 qPCR assay was linear from 5.9 × 10(6) to 59 genome equivalents per reaction. Both the LipL32 and the rrs qPCR assays showed a limit of detection of 10 target copies per reaction indicating an approximately equivalent analytical sensitivity. Both assays amplified all 20 pathogenic leptospiral strains tested but did not amplify a representative collection of bacteria commonly found in voided canine urine. When the field samples were assayed, 1 and 5 out of 184 samples yielded an amplification signal in the LipL32 and rrs assays, respectively. Nevertheless, when the limit of detection was considered as the cutoff for interpreting findings, the 4 discordant cases were judged as negative. In conclusion, our study confirmed that both LipL32 and rrs are suitable targets for qPCR for the detection of leptospiral DNA in canine urine. However, the rrs target requires the mandatory use of a cutoff value in order to correctly interpret spurious amplifications.

  11. Preliminary Characterization of Mus musculus–Derived Pathogenic Strains of Leptospira borgpetersenii Serogroup Ballum in a Hamster Model

    Science.gov (United States)

    da Silva, Éverton F.; Félix, Samuel R.; Cerqueira, Gustavo M.; Fagundes, Michel Q.; Neto, Amilton C. P. S.; Grassmann, André A.; Amaral, Marta G.; Gallina, Tiago; Dellagostin, Odir A.

    2010-01-01

    Human and animal leptospirosis caused by Leptospira spp. belonging to serogroup Ballum has increased worldwide in the past decade. We report the isolation and serologic and molecular characterization of four L. borgpetersenii serogroup Ballum isolates obtained from Mus musculus, and preliminary virulence studies. These isolates are useful for diagnosis of leptospirosis and for epidemiologic studies of its virulence and pathogenic mechanisms. PMID:20682877

  12. Spatial characterization of Leptospira spp. infection in equids from the Brejo Paraibano micro-region in Brazil

    Directory of Open Access Journals (Sweden)

    Ruy Brayner Oliveira Filho

    2014-05-01

    Full Text Available The present study, the first to spatially characterize Leptospira spp. infection among equids in the Brejo Paraibano micro-region of the Paraiba state in the northeast of Brazil, investigated 257 animals in 26 farms properties. Serum samples from 204 horses, 46 mules and seven donkeys were serologically diagnosed using the microscopic agglutination test (MAT. The distribution of Leptospira spp. was studied by employing specific antigens from 24 different Leptospira serovars. All farms were georeferenced and their distribution visualised on a map of the Brejo Paraibano micro-region. In addition, rainfall data were obtained from the same year, in which the sampling was performed. Among the 20 farms found to harbour animals with leptospirosis, 14 (70% exhibited low prevalence, five (25% medium prevalence and one (5%, high prevalence. Certain areas had a higher density of infected farms and required intervention to control the infection. Many serovars were widely distributed, while others were more common in particular areas. There was no significant association between the prevalence of Leptospira spp. infection and rainfall.

  13. Spatial characterization of Leptospira spp. infection in equids from the Brejo Paraibano micro-region in Brazil.

    Science.gov (United States)

    Oliveira Filho, Ruy Brayner; Campos Malta, Karla; Assis Santana, Vania Lucia; Vance Harrop, Mabel Hanna; Tancler Stipp, Danilo; Friguglietti Brandespim, Daniel; Aparecido Mota, Rinaldo; Wilton Pinheiro Júnior, José

    2014-05-01

    The present study, the first to spatially characterize Leptospira spp. infection among equids in the Brejo Paraibano micro-region of the Paraiba state in the northeast of Brazil, investigated 257 animals in 26 farms properties. Serum samples from 204 horses, 46 mules and seven donkeys were serologically diagnosed using the microscopic agglutination test (MAT). The distribution of Leptospira spp. was studied by employing specific antigens from 24 different Leptospira serovars. All farms were georeferenced and their distribution visualised on a map of the Brejo Paraibano micro-region. In addition, rainfall data were obtained from the same year, in which the sampling was performed. Among the 20 farms found to harbour animals with leptospirosis, 14 (70%) exhibited low prevalence, five (25%) medium prevalence and one (5%), high prevalence. Certain areas had a higher density of infected farms and required intervention to control the infection. Many serovars were widely distributed, while others were more common in particular areas. There was no significant association between the prevalence of Leptospira spp. infection and rainfall.

  14. Exposure of free-ranging wild carnivores, horses and domestic dogs to Leptospira spp in the northern Pantanal, Brazil.

    Science.gov (United States)

    Jorge, Rodrigo Silva Pinto; Ferreira, Fernando; Ferreira Neto, José Soares; Vasconcellos, Silvio de Arruda; Lima, Edson de Souza; Morais, Zenaide Maria de; Souza, Gisele Oliveira de

    2011-06-01

    Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres ≥ 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species.

  15. Prevalencia de anticuerpos contra Leptospira en personas asintomáticos y en perros de Chancay, Lima 2001

    Directory of Open Access Journals (Sweden)

    Manuel Céspedes

    2007-10-01

    Full Text Available Objetivos. Determinar la prevalencia de anticuerpos contra Leptospiras en personas asintomáticas dedicadas a la agricultura, pesca y comercio y en perros domésticos de localidades de Chancay (Huaral, Lima. Material y métodos. Estudio transversal analítico, se tomó muestras de suero de 268 pobladores de tres localidades, en quienes se evaluó la presencia de anticuerpos totales contra Leptospiras por el método de ELISA IgG y la prueba de microaglutinación (MAT. Se buscaron los factores asociados con la positividad a Leptospiras calculando el OR con su intervalo de confianza al 95%. De la misma manera, se tomó muestras de suero de 241 perros a los que se realizó la prueba de MAT. Resultados. La prevalencia de anticuerpos contra Leptospira en población asintomática fue de 10,1% (IC95%: 6,3-13,9, la cual estuvo asociada con el abastecimiento de agua para consumo en quebrada o pozo (OR: 3,48, IC95%: 1,39-8,74, con el antecedente de nadar en el río o acequia (OR: 4,75, IC95%: 1,51-14,92 y con tener una edad entre 21-40 años (OR: 2,47, IC95%: 1,10-5,52. Los serovares más frecuentes fueron Icterohaemorrhagiae y Canicola según MAT. En canes, 27,8% (67/241 tuvieron serología positiva a leptospiras. Conclusiones. Existe una mediana prevalencia de serología positiva para Leptospiras en la población general asintomática y condiciones favorables para la presencia de Leptospiras en las localidades estudiadas. En estas zonas se recomienda realizar actividades educativas preventivas frecuentes, tomando en cuenta los resultados de este estudio y el personal de salud debe sospechar de la leptospirosis como una causa de enfermedad febril.

  16. Epidemiological observation on effect of Leptospiral outer membrane vaccine%钩端螺旋体外膜菌苗流行病学效果研究

    Institute of Scientific and Technical Information of China (English)

    程均福; 秦进才; 谢广中; 张锦麟; 张流波; 丁建平; 严有望; 张新炳

    2001-01-01

    Objective To study the safety and effect of Leptospiral outer membrane vaccine. Methods Eighty thousands dosages of Leptospiral outer membrane vaccine were vaccinated in Jingzhou and Shishou city Hubei prevince. Temperaure, side-effects such as Local edema with in 48 hours as well as the incidence of Leptospirsis within a year among those were vaccinated and unvaccinated were observed. Results (1)No any severe side-effect and abnormal reaction, was found, only 2 case suffered from slight fever and local edema which receded in 48 hrs. (2) Effects of Leptospiral outer membrane vaccine were as follows: 2 cases were attacked by lcterohaemorrhagiae in vaccination group and 47 cases in control group, so the protection rate 95.57% and confidence interval (CI) was 85.43%-98.20%. Fifteen hebdomadis cases were found in control group. The protection rate of this vaccine reached 100.00%, CI 77.08%-100.00%. Conclusion Safty and protective effect were well showed when type of bacteria was concordant with that in vaccination district.%目的 证实钩端螺旋体外膜菌苗的安全性和免疫效果。方法 在湖北省荆州市和石首市现场接种钩端螺旋体外膜菌苗80 000人份,观察48 h内体温、局部红肿等副反应和一年内接种钩端螺旋体外膜菌苗者发病情况,同时设对照组。结果 所有钩端螺旋体外膜菌苗接种者未见严重副反应和异常反应,仅2例菌苗接种者有低热和局部红肿,48 h后消失,安全性良好。接种组发生黄疸出血群钩端螺旋体病人2例,对照组发生黄疸出血群钩端螺旋体病人47例,黄疸出血群钩端螺旋体外膜菌苗保护效果95.57%,95%可信限为85.43%~98.20%;对照组发生七日热群钩端螺旋体病人15例,七日热群钩端螺旋体外膜菌苗有效率100.00%,95%可信限下限77.08%。结论 钩端螺旋体外膜菌苗安全性良好,接种与疫区流行菌群一致的钩端螺旋体外膜菌苗,可以取

  17. Evidencia de exposición a Leptospira en perros callejeros de Cali.

    Directory of Open Access Journals (Sweden)

    Ana Lucía Rodríguez

    2004-09-01

    Full Text Available En Cali, y en Colombia en general, se desconoce la epidemiología de la leptospirosis en ambientes urbanos. Además, el papel del perro en el ciclo de transmisión en dichos ambientes no es claro. Para explorar esta situación, realizamos un estudio serológico en Cali a 197 sueros de perros callejeros durante el 2001 y el 2003, utilizando la prueba de microaglutinación (MAT. En la prueba se incluyeron 7 serovares: Icterohaemorrhagiae, Canicola, Gryppotyphosa, Hardjo cepa Hardjobovis, Pomona, Hardjo cepa Hardjoprajitno y Bratislava aportados por el Instituto Colombiano Agropecuario (ICA de Tuluá. La prueba se interpretó como positiva por la presencia de una aglutinación ³50% de las leptospiras, con uno o más serovares, en una dilución del suero ³1:100. Encontramos evidencia de infección en el 41,1% de los perros con, al menos, uno de los serovares. La mayor reactividad fue a Icterohaemorrhagiae con 55,6% del total de los seropositivos. Se presentaron 48,1% de coaglutinaciones. No se registraron reacciones contra los serovares Pomona, Hardjo cepa Hardjoprajitno y Bratislava. Estos hallazgos sugieren que el perro callejero es un posible reservorio de leptospira en Cali y resaltan la necesidad de estudiar la epidemiología de la enfermedad en esta ciudad.

  18. Development of chronic and acute golden Syrian hamster infection models with Leptospira borgpetersenii serovar Hardjo.

    Science.gov (United States)

    Zuerner, R L; Alt, D P; Palmer, M V

    2012-03-01

    The golden Syrian hamster (Mesocricetus auratus) is frequently used as a model to study virulence for several Leptospira species. Onset of an acute lethal infection following inoculation with several pathogenic Leptospira species has been widely adopted for pathogenesis studies. An important exception is the outcome following inoculation of hamsters with live L. borgpetersenii serovar Hardjo, the primary cause of bovine leptospirosis and a cause of human infections. Typically, inoculation of hamsters with L. borgpetersenii serovar Hardjo fails to induce clinical signs of infection. In this study, the authors defined LD(50) and ID(50) for 2 strains of L. borgpetersenii serovar Hardjo: JB197 and 203. Both strains infected hamsters with ID(50) values of approximately 1.5 × 10(2) bacteria yet differed in tissue invasion and interaction with leukocytes, resulting in widely divergent clinical outcomes. Hamsters infected with strain 203 established renal colonization within 4 days postinfection and remained asymptomatic with chronic renal infections similar to cattle infected with serovar Hardjo. In contrast, hamsters infected with strain JB197 developed a rapidly debilitating disease typical of acute leptospirosis common in accidental hosts (eg, humans) with an LD(50) of 3.6 × 10(4) bacteria. Evidence that strain JB197 resides in both extracellular and intracellular environments during hamster infection was obtained. Development of models that result in chronic and acute forms of leptospirosis provides a platform to study L. borgpetersenii pathogenesis and to test vaccines for the prevention of leptospirosis.

  19. Discovery of Novel Leptospirosis Vaccine Candidates Using Reverse and Structural Vaccinology

    Directory of Open Access Journals (Sweden)

    Alan John Alexander McBride

    2017-04-01

    Full Text Available Leptospira spp. are diderm (two membranes bacteria that infect mammals causing leptospirosis, a publi