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1.
Outer sheath antigen from Leptospira interrogans serovar hardjo type hardjoprajitno and acetic acid extracted antigens from serovar hardjo types hardjoprajitno and hardjobovis were evaluated in an immunoassay for ability to detect hyperimmune rabbit serum to serovar hardjo. The degree of cross-reactivity with hyperimmune rabbit sera to L. interrogans serovars pomona, copenhageni, grippotyphosa, canicola and sejroe, and Leptospira biflexa serovar patoc was also measured for each antigen. All of the antigens reacted with the antiserum to L. interrogans serovar hardjo. The outer sheath antigen however, also showed wide cross-reactivity with the antisera to all of the serovars of L. interrogans tested and with the antiserum to L. biflexa serovar patoc. The acetic acid extracted antigen from either type hardjoprajitno, or type hardjobovis, showed a high degree of specificity for serovar hardjo antiserum. The hardjobovis acetic acid extracted antigen was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting, and was incorporated into an indirect ELISA for detection of anti-serovar hardjo antibodies in bovine serum. This ELISA showed a relative specificity of 100% with 156 bovine sera which were negative at a dilution of 1:100 in the microscopic agglutination test (MAT) for L. interrogans serovars hardjo, pomona, sejroe, icterohaemorrhagiae, copenhageni, canicola, and grippotyphosa. The relative sensitivity of this assay with 192 bovine sera which had serovar hardjo MAT titres of > or = 100 was 95.3% (95% confidence limit = 2.99%). The degree of cross-reactivity with 289 bovine sera which had serovar pomona MAT titres of > or = 100 (with no detectable serovar hardjo MAT titres) was approximately 1.0%. This assay was: easily standardized, scored objectively, repeatable, semi-automated and used a non-hazardous antigen that can be routinely prepared in gram amounts.  相似文献   

2.
OBJECTIVE: To evaluate serum titers obtained by use of the microscopic agglutination test (ie, MAT titers) to Leptospira interrogans serovar pomona and autumnalis and Leptospira kirschneri serovar grippotyphosa in dogs given a commercial vaccine against serovars pomona and grippotyphosa. ANIMALS: Forty 12-week-old puppies and 20 mature Beagles. PROCEDURE: Puppies received a commercial vaccine against serovars pomona and grippotyphosa at 12 weeks of age, then received a booster vaccine and 3 weeks later; mature dogs received the vaccine once. Serum MAT titers to serovars pomona, autumnalis, and grippotyphosa were measured before vaccination and at 2, 4, 6, 10, and 16 weeks after the first or only vaccination. RESULTS: Of the 40 puppies vaccinated, 40, 0, and 40 developed MAT titers of > 100 after vaccination to serovars pomona, grippotyphosa, and autumnalis, respectively. Microscopic agglutination test titers to serovar autumnalis were higher than MAT titers to serovars pomona and grippotyphosa and persisted in some dogs for 16 weeks (6 weeks longer than for titers to serovar pomona). Of the 20 mature dogs, 13, 5, and 20 developed MAT titers of > 100 at 2 weeks to serovars pomona, grippotyphosa, and autumnalis, respectively. Titers to serovar pomona were higher and persisted in some dogs beyond 16 weeks after vaccination, compared with titers to serovars pomona and grippotyphosa, which persisted for 10 and 6 weeks, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Subunit vaccines against serovars pomona and grippotyphosa induce MAT titers not only to homologous antigens but also to serovar autumnalis, which could lead to a misdiagnosis of leptospirosis caused by serovar autumnalis.  相似文献   

3.
In 1998, a total of 424 sows had sera collected in the Mekong delta in Vietnam. Of these, 283 sows were from 151 small-scale family farms in 19 villages, and 141 from seven large-scale state farms. The sera were subjected to the microscopic agglutination test (MAT) for antibodies to 13 Leptospira serovars. The overall leptospiral seroprevalence for titres > or =1:100 and > or =1:400, was 73 and 29%, respectively, and was higher (P=0.001) at small- than at large-scale farms. The highest seroprevalence was recorded for Leptospira interrogans serovar (sv) bratislava (52%). At small-scale farms, higher prevalences were found to serovars L. interrogans sv icterohaemorrhagiae (P=0.04) and L. interrogans sv pomona (P=0.02).Epidemiological information (at the individual-animal and herd-levels) was collected with a questionnaire. The data were analysed using logistic multiple regression. At the animal-level, sows seropositive for L. interrogans sv australis and sv autumnalis had less direct contact with sows in neighbouring pens (odds ratio (OR)=0.3 and 0.4, respectively) and sows seronegative for L. interrogans sv bratislava were of lower age (OR=0.1 for seropositivity). Also, sows seropositive for L. interrogans sv icterohaemorrhagiae had higher odds (OR=5.8) if they had not been born on the farm (had been introduced to it as gilts).Herds seropositive for sv javanica showed association with farms not taking measures to control the local rodent population (OR=7.8). Serovar pomona was also linked to the use of artificial insemination (AI), as opposed to natural-breeding services (OR=11.2).These results indicate that housing and management could affect the seroprevalence of Leptospira infection in pigs.  相似文献   

4.
Outer sheath antigen was prepared from Leptospira interrogans serovars pomona, sejroe and hardjo by treating the organisms with 1.0M NaC1 followed by 0.04% sodium dodecyl sulfate (SDS). Sodium dodecyl sulfate was removed from the SDS-protein complexes by the extraction of dodecyl sulfate anions as ion pairs with triethylammonium cations into an organic solvent. The outer sheath antigen was recovered from the organic solvent as a precipitate and used as the source of leptospiral enzyme-linked immunosorbent assay (ELISA) antigen. Utilizing this antigen, ELISA was adapted to detect bovine serum antibody to L. interrogans serovars pomona, sejroe and hardjo. The specificity of this assay in 344 bovine sera, which were negative in the microscopic agglutination test (MAT) for seven serovars, was 99.4%. In sera from 37 and 87 cattle which revealed MAT titers greater than or equal to 1:50 for L. interrogans serovars pomona and sejroe, the relative sensitivity of the test was 100%. The ELISA also showed a considerable degree of low level cross-reactivity with other serovars. Sixty-six (75.9%) out of 87 bovine sera which were MAT-positive (MAT titer of greater than or equal to 1:50) with serovars sejroe and hardjo only were ELISA positive with heterologous pomona antigen; 16 (43.2%) and six 16.2%) out of 37 bovine sera which were MAT positive MAT titer of greater than or equal to 1:50) with serovar pomona only were ELISA positive with heterologous sejroe and hardjo ELISA antigen respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
Serum samples obtained from 1.537 cattle in the 14 local government areas (LGAs) of Plateau State of Nigeria were screened for the presence of leptospiral antibodies using 13 serovars in a modified microscopic agglutination test (MAT). Two hundred and twenty-two (14.4 p.100) of the cattle tested had leptospiral antibody titres of 1:100 or higher to one or more of the test antigens. The prevalence rates of antibodies to individual serovars were: hardjo (35.6 p.100), pomona (11.7 p.100), pyrogenes (11.7 p.100), canicola (9.5 p.100), grippotyphosa (7.7 p.100), bratislava (5.9 p.100), icterohaemorrhagiae (5.9 p.100), ballum (4.5 p.100), autumnalis (3.6 p.100), bataviae (2.3 p.100) and tarassovi (1.8 p.100). The serological prevalence of bovine leptospirosis in the various local government areas of Plateau State of Nigeria differed significantly (P less than 0.05; X2).  相似文献   

6.
Three monoclonal antibodies produced against Leptospira interrogans serovar pomona have been studied for their diagnostic usefulness. All three monoclonals reacted strongly in the enzyme-linked immunosorbent assay and indirect fluorescent antibody test with serovar pomona and did not react with serovars grippotyphosa, canicola, icterohaemorrhagiae and hardjo.  相似文献   

7.
The occurrence of leptospirosis in swine of southeastern Alabama was determined. A total of 627 sera were tested, using the microscopic agglutination method, with live antigens of 12 serovars. Of the sera tested, 121 (19.3%) had a titer of 1:100 or greater to the serovars employed. The percentage distribution of sera with titers of greater than or equal to 1:100 among serovars most commonly reported was as follows: Leptospira interrogans serovars pomona, 3.8%; icterohaemorrhagiae, 3.3%; canicola, 1.6%; hardjo, 0.7%; and grippotyphosa, 0.16%. Of the less commonly recognized leptospiral serovars, the percentages reacting were as follows: ballum, 4.9%; autumnalis, 3.2%; pyrogenes, 1.1%; and bataviae, 0.4%. None of the sera reacted with antigen of serovars australis, tarassovi, or wolffi.  相似文献   

8.
Leptospirosis in horses in Ontario.   总被引：6，自引：1，他引：5       下载免费PDF全文
Sera from Thoroughbred and Standardbred horses in southwest Ontario were tested for antibody to seven Leptospira interrogans serovars (autumnalis, bratislava, canicola, grippotyphosa, hardjo, icterohaemorrhagiae, pomona), using the microscopic agglutination test. There was significantly higher seroprevalence of bratislava than of other serovars, in which prevalence was low. Seroprevalence of bratislava increased significantly with age; only 5% of two to three year old horses had titers greater than or equal to 1:80 compared to 52% of horses older than seven years. Eight of 16 foals from two farms seroconverted at low titers to bratislava between four and eight months of age. Leptospires were not detected by immunofluorescence and isolation techniques in 50 kidneys collected from horses at slaughter. Fetal tissues from 52 aborted horse fetuses were also examined by these methods and serovar kennewicki was identified by immunofluorescence and by isolation in one fetus. Serovar bratislava appears to be widespread in horses in Ontario but unimportant in abortion. The clinical significance of this infection in horses in Ontario is unclear.  相似文献   

9.
A biotin/avidin double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of antigens of Leptospira interrogans serovars in experimentally inoculated bovine urine samples was evaluated. Immunoglobulin G (IgG) from rabbits immunized with L. interrogans serovar hardjo type hardjobovis sonicated, whole cell, and formalinized-heated antigen preparations were purified by a protein A-superose column coupled to fast protein liquid chromatography, and evaluated for species specificity in the ELISA. The ELISA using each specific IgG detected as few as 10(4) leptospires of the homologous serovar hardjo diluted in phosphate-buffered saline solution with Tween 20 (PBSS-Tween 20). On immunoblot analysis of proteinase-K-digested whole cell leptospiral preparations, each IgG revealed the presence of bands specific to serovar hardjo, suggesting the presence of serovar-specific epitopes on the lipopolysaccharide molecules. The minimum number of cells of heterologous serovars pomona, grippotyphosa, bratislava, icterohaemorrhagiae and copenhageni detected by each ELISA was greater, ranging from 10(6) to 10(7). The common antigenic determinants observed on immunoblot analysis were different for each specific IgG, except for a major cross-reacting, possibly flagellar, protein doublet at approximately 36-36.5 kDa. Leptospires were equally well detected by the ELISA in both bovine urine and PBSS-Tween 20.  相似文献   

10.
A murine monoclonal antibody (designated M553) that binds to an epitope on whole cell antigens prepared from Leptospira borgpetersenii serovar hardjo type hardjobovis and Leptospira interrogans serovar hardjo type hardjoprajitno, was produced and incorporated into a competitive enzyme-linked immunosorbent assay for the detection of bovine antibodies to serovar hardjo. The epitope recognized by M553 was susceptible to periodate oxidation. The M553 antibody was characterized by western blot with hardjobovis whole cell antigen. This antibody does not cross-react with whole cell antigens prepared from 11 other pathogenic Leptospira serovars, or, Leptospira biflexa serovar patoc. The sensitivity estimate of the competitive ELISA was 100% with field sera (n = 165) with serovar hardjo microscopic agglutination test (MAT) titres of > or = 100. The specificity estimate was 100% with sera (n = 128) obtained from a specific pathogen free herd of cattle that were negative in the MAT at a dilution of 1:100 for serovars hardjo, pomona, sejroe, copenhageni, canicola, and grippotyphosa. The specificity estimate with field sera (n = 301) with serovar hardjo MAT titres of < 100, was 98% (95% confidence interval = +/- 1.58%). There was no cross-reactivity with field sera (n = 306) with serovar pomona titres > or = 100 and serovar hardjo titres < 100. The specificity estimate with the combined populations of sera with serovar hardjo MAT titres of < 100 (n = 735) was 99.18% (95% confidence interval = +/- 0.65%). There was a high level of agreement (kappa = 0.977) between the results of the competitive ELISA and those of the MAT.  相似文献   

11.
Monoclonal antibodies (mAb) were produced by fusing Sp2/0-Ag14 myeloma cells with spleen cells from BALB/c and ND4 mice that were immunized with killed Leptospira interrogans serovar pomona whole cells. Thirty hybridomas which produced antibodies (of the IgG1, IgG2a, IgG2b, or IgG3 isotype) that bound to epitopes on the serovar pomona whole cell antigen were identified by an indirect enzyme-linked immunosorbent assay (ELISA). Twenty-eight of these 30 mAbs cross-reacted in the indirect ELISA with at least one whole cell antigen prepared from 12 other pathogenic Leptospira serovars, and/or with whole cell antigen from the non-pathogenic Leptospira biflexa serovar patoc. The two serovar pomona-specific mAbs, which were designated M897 and M898, were obtained from the ND4 mouse and were both of the IgG1 isotype. In competitive ELISAs, M897 and M898 were inhibited from binding to the pomona antigen by bovine sera with anti-serovar pomona microscopic agglutination test (MAT) titres ranging from 100 to 6400. No significant inhibition was observed with pomona MAT-negative sera or with sera from animals experimentally infected with serovars canicola, copenhageni, grippotyphosa, hardjo type hardjobovis or sejroe. The epitopes recognized by M897 and M898 were both highly susceptible to sodium meta-periodate oxidation, indicating a carbohydrate composition. Neither of these mAbs reacted in immunoblots with the separated components of the serovar pomona whole cell antigen.  相似文献   

12.
The clinical features of the disease are presented based on retrospective analysis of the records of eleven dogs diagnosed with leptospirosis using clinical signs and results of the microagglutination test (MAT) between 1991 and 1996. Additionally, Leptospira titres were determined in 30 healthy dogs and 20 hospitalised dogs without clinical or laboratory evidence of leptospirosis. A positive titre for L. grippotyphosa, L. pomona, L. bratislava, L. australis, L. icterohaemorrhagiae and/or L. canicola was found in 16 normal dogs and only one hospitalised patient. Eight of these dogs had titres of > or = 1:800. Only one of them had been vaccinated shortly before sampling. These results suggest that many dogs from the surroundings of Bern, Switzerland have contact with various Leptospira interrogans serovars. In ten healthy dogs, the Leptospira titre was determined before and four weeks after vaccination with leptospiral antigen. Only two of the dogs showed a serologically measurable response to the antigen contained in the vaccine. In dogs MAT titers presumably do not reliably reflect the immune status against leptospiral infections.  相似文献   

13.
In cows inoculated with Leptospira interrogans serovar pomona or hardjo, the 2-mercaptoethanol-sensitive microscopic agglutination test (MAT) antibody to the serovar appeared 3 to 8 days after inoculation and peaked at 10 to 20 days, whereas the 2-mercaptoethanol-resistant MAT antibody was predominant at 35 to 80 days. A persistent antibody response, probably associated with serovar-specific leptospiral antigens, was detected in the cows inoculated with serovar pomona, using a sonicated or an alkaline-extracted antigen derived from serovar pomona in the enzyme-linked immunosorbent assay (ELISA). In contrast, a short-lived antibody response to the same antigens was demonstrated in cows inoculated with serovar hardjo, probably more typical of the response to genus-specific leptospiral antigens. Antigens derived from L biflexa serovar patoc only detected the latter type of antibody response in cows inoculated with serovar pomona or hardjo. Correlative studies revealed that the antigens derived from serovar patoc seem to be genus specific and serologically closely related, but not identical. The antigens derived from serovar pomona were genus specific on the basis of the early antibody response to leptospiral inoculation in the cows, but serovar specific based on the subsequent more persistent response to leptospiral inoculation. These antigens were also serologically closely related, but not identical. Examination of sera from cows that aborted and were MAT-positive for serovar pomona or hardjo revealed a more serovar-specific antibody response, indicating that there may have been a less recent leptospiral antigenic stimulus, thus emphasizing the caution with which results of the ELISA and other serologic assays for the detection of bovine leptospirosis must be interpreted.  相似文献   

14.
A serological survey was conducted among sows in the Mekong delta in southern Vietnam in 1999 to investigate variations in leptospiral Seroprevalence over a one-year period. In this region, leptospirosis is endemic and a high leptospiral Seroprevalence has been shown in the pig population. In this study, the serology of six Leptospira serovars was analysed by the microscopic agglutination test for 429 sows at five large-scale state farms sampled during the dry period, the rainy period and the early dry period. The serovars included were L. interrogans serovar (sv) autumnalis strain Akiyama A, L. interrogans sv bratislava strain Jez, L. interrogans sv icterohaemorrhagiae strain Kantorowicz, L. interrogans sv pomona strain Pomona, L. borgpetersenii sv tarassovi strain Perepelitsin, and L. kirschneri sv grippotyphosa strain Duyster. Variations in Seroprevalence over the year were found for sv bratislava and sv icterohaemorrhagiae: the Seroprevalence was higher during the dry period compared with the rainy period (p = 0.07 and p = 0.005, respectively) and the early dry period (p = 0.00006 and p = 0.0006, respectively). It is concluded that in regions where water is constantly abundant and where animals are exposed to the outdoor environment all year round there are highly significant variations in leptospiral Seroprevalence over the year.  相似文献   

15.
Two dogs with clinical histories suggestive of leptospirosis were examined serologically and culturally for evidence of leptospiral infection. Antibodies to Leptospira interrogans serovar bratislava were detected in serum from one dog, and the organism was isolated from urine of that dog. In a serologic survey of dogs in the state of Illinois, reactor rates to bratislava were higher than those to canicola or icterohaemorrhagiae. In cases of suspect canine leptospirosis, serovars such as bratislava, not contained in canine vaccines, should be considered in a differential diagnosis.  相似文献   

16.
In 1985-1988, 993 serum samples of dogs from Southern Bavaria and 408 samples from Northern Bavaria and from several Lands of the Federal Republic of Germany were tested for antibodies against the serovars canicola, icterohaemorrhagiae, grippotyphosa, bratislava, pomona, saxkoebing, sejroe and hardjo by using the microscopic agglutination test (MAT). 683 seras (48.75%) out of altogether 1401 samples showed a reaction against one up to seven serovars. The mostly low canicola- and icterohaemorrhagiae titers, having been proved in over 30% of the samples, can be put down to the fact, that usually the dogs had been vaccinated. Most frequently titers were found with the serovars grippotyphosa and bratislava--in Southern Bavaria 28.3%, in Northern Bavaria and other Lands of the Federal Republic of Germany 18.6%. The prevalence of titers against serovar saxkoebing, with or without a reaction against other serovars out of homologous and heterologous serogroups, reach up to 3.2% in sendings coming from Southern Bavaria and in other sendings up to 6.1%.  相似文献   

17.
Serology plays an important role in laboratory diagnosis of leptospirosis. Apart from the most often used microscopic agglutination test (MAT), enzyme-linked immunosorbent assay (ELISA) seems to be useful especially in screenings of animal herds. The ELISA used for detection of antibodies against selected Leptospira serogroups in swine serum samples was investigated during the study. An essential element of this test is heat-stable antigenic preparation from cultures of Leptospira interrogans serovars Icterohaemorrhagiae, Pomona and L. borgpetersenii serovar Sejroe. The aim of the present study was to identify and analyze ELISA heat-stable antigen fractions playing a role in the reaction with leptospiral antibodies indicated in swine serum. Reactivity of the three-component antigenic preparation was compared in immunoblotting with reactivity of six heat-stable antigenic preparations made from the following single serovars: L. interrogans serovars Icterohaemorrhagiae, Pomona, Canicola, L. borgpetersenii serovars Sejroe, Tarassovi and L. kirshneri serovar Grippotyphosa. All antigenic preparations were submitted to SDS-PAGE and transferred to a nitrocellulose membrane using a semidry system. After the transfer, the membrane was incubated with diluted swine serum containing antibodies specific for one of the six above mentioned Leptospira serovars. For the three-component antigenic preparation and antigens prepared from single serovars the immunoblot revealed reaction of sera with fractions of the 20-26 kDa region and around the 14.5 kDa region. The investigated heat-stable Leptospira antigenic preparation contains fractions demonstrating serogroup- and species-specificity. Fraction 20-26 kDa showed serogroup-specific activity, whereas the fraction around 14.5 kDa showed species-specific activity.  相似文献   

18.
The prevalence of Leptospira interrogans serovars in dairy cattle was determined by analyzing 464 serum samples from cows on 15 properties in Garanhuns municipal district, Pernambuco State, Brazil. A microscopic seroagglutination test including 12 serovars of Leptospira interrogans as antigens was used. Samples with titres 100 were considered positive. Two hundred and twenty-one (47.63%) of the samples were positive to one or more serovars. The prevalence of the serovars was hardjo (21.98%), bratislava (15.73%), castellonis (11.64%), tarassovi (10.56%), pyrogenes (1.72%), icterohaemorrhagiae (1.08%), pomona (0.86%), wolffi (0.86%), grippotyphosa (0.86%), djasiman (0.43%), canicola (0.21 %), and copenhageni (0.21%).  相似文献   

19.
Sera were collected using a systematic random sampling from 348 cattle herds in Ontario, in proportion to the cattle population in different areas. One cow in five from 296 dairy herds and one in three from 52 beef herds were sampled. The sera were analyzed for prevalence of antibodies to Leptospira interrogans serovar grippotyphosa, hardjo, icterohaemorhagiae and pomona using the microscopic agglutination test. Herd seroprevalence (one or more animals with titer greater than or equal to 80) in beef and dairy herds combined was grippotyphosa 2%, hardjo 13.8%, icterohaemorrhagiae 10.1% and pomona 25.8%; 39% of all herds showed evidence of leptospiral infection with one or more serovars; 44.2% of 52 beef herds had serological evidence of infection with serovar hardjo compared to 8.4% of 296 dairy herds (P less than 0.0001). Seroprevalence of other serovars was not significantly different between beef and dairy herds. The proportion of beef animals seropositive for hardjo and for pomona increased with age, particularly for hardjo; 26.5% of beef animals aged nine years or over were seropositive for hardjo. Dairy animals showed a significant rise of hardjo but not pomona titers with age. The seroprevalence of pomona infection was significantly higher in dairy cattle in eastern Ontario than in other regions. Thirty-four (6.1%) of 553 aborted bovine fetuses had leptospires detected by immunofluorescence techniques. Sixty-five percent of these fetuses were from submissions made between November and January. Leptospires were identified as serovar hardjo by specific immunofluorescence. There appeared, however, to be a paradoxical serological response in that eight aborting cows had antibody titers to pomona rather than hardjo.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
Clinical and serological evidence has indicated that human leptospirosis in Fiji is an important disease, and the prevalence of antibody is exceptionally high. A serological survey of the rural population showed that only 12% of the people studied did not have complement fixing (CF) leptospiral antibody. As the origin of this infection could not be explained by the known distribution of leptospiral infection in domestic and wild animals, a serological survey using the complement fixation test (CFT) was undertaken as the first stage of an epidemiological investigation into human and animal leptospirosis. Sera from domestic and wild animals were tested for CF antibody to 12 leptospiral serovars, namely: pomona, copenhageni, grippotyphosa, hardjo, ballum, tarassovi, canicola, australis, bratislava, autumnalis, pyrogenes and bataviae. Antibody was detected in 27.5% of 480 cattle, 17.1% of 70 sheep, 10.3% of 252 goats, 10.0% of 480 pigs, 57.0% of 100 dogs, 55.8% of 34 rats (Rattus rattus, R. frugivorus, R. exulans and R. norvegicus), 53.1% of 32 mongooses (Herpestes auropunctatus) and 40.0% of 10 mice (species unknown.) Cross-reactivity precluded the identification of infecting serogroups with the exception of pomona in pigs and icterohaemorrhagiae, ballum and australis in dogs. Infection of dogs with a serovar of the australis serogroup may explain the predominance of serological reactions to bratislava in man. The survey revealed a significant level of leptospiral antibody in the animal populations of Fiji and indicated that cattle, dogs, rats, mongooses and mice are probably the most important maintenance hosts. Consequently, further investigation will concentrate on the attempted isolation of leptospires from these species.  相似文献   

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