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PubMed2006

Western immunoblot analysis using a ten leptospira serovars combined antigen for serodiagnosis of leptospirosis.

Leptospirosis is a major zoonotic disease throughout the world. There are unavailable accuracy diagnostic methods for the acute phase of infection. To demonstrate the advantage of Western immunoblot, a mixed leptospira serovars antigen for the serodiagnosis of leptospirosis was employed. SDS-PAGE and Western immunoblot was performed using a 10 mixed leptospira serovars antigen and stained with 16 reference rabbit anti-leptospirosis antibodies. The result showed different immunoreactive band patterns for each reference serum. The bands with molecular weights of 15-20, 23-24, 41 and 45 kDa were commonly found (88% to 100% of the 16 reference sera). Using combined leptospira antigens in a Western immunoblot technique is an alternative and practical strategy for a more sensitive leptospirosis serodiagnosis.

Antibodies, Bacterial↗

PubMed2006

Immunoreactive outer membrane proteins of Leptospira interrogans serovar Canicola strain Hond Utrecht IV.

BACKGROUND & OBJECTIVES: Leptospirosis is a severe and complex zoonotic disease prevalent in many countries including India. Current leptospiral research is focussed on the identification of the outer membrane proteins (OMPs) of the organism that could be used in developing diagnostic assays for leptospirosis. METHODS: The Leptospira interrogans serovar Canicola was grown in EMJH medium and the cells were subjected to sarcosyl detergent treatment. The sarcosyl soluble (SS) and sarcosyl insoluble (SI) fractions were analyzed by SDS-PAGE and immunoblotting to deduce their protein profile and identifying various immunodominant antigens. RESULTS: The protein profile of SS fractions indicated the presence of three major bands of 41, 32 and 25 kDa and minor bands of 85 and 46 kDa. The SI fraction in serovar Canicola revealed the presence of 112, 93, 77, 43, 36, 29 and 22.5 kDa as major bands and minor bands of 102 and 53 kDa. In immunoblotting, the SS proteins of 41, 32 and 25 kDa and SI proteins of 112, 77, 36 and 22.5 kDa were detected to be major immunogenic proteins. INTERPRETATION & CONCLUSION: In our study immunogenic proteins were extracted from SS and SI fractions and OMPs were similar to those reported in other pathogenic Leptospira strains. These OMPs being unique to all the pathogenic leptospires, can be targeted for diagnostic purpose. Further analysis of the cellular location and expression of leptospiral proteins will be useful in the annotation of genomic sequence data and in providing insight into the biology of Leptospira cells.

Animals↗

PubMed1988

Fatty acids as resource of carbon for leptospirae.

The effect of saturated (palmitic, stearic, myristic) and unsaturated (oleic) fatty acids on the proliferation of Leptospirae was studied. Proliferation of the saprophytic strains G-45, K-1028 (serovar not identified) and of the pathogenic strain VGNKI-3 (serovar canicola) of Leptospirae was obtained on a serum-free medium with the addition of saturated fatty acids. The unsaturated oleic acid at relatively high concentrations (0.5 mg/ml) suppresses proliferation of these spirochetes. It has been demonstrated that the variants used in the experiment can be utilized for the study of nutritional requirements of Leptospirae and their metabolism.

Culture Media↗

PubMed1986

Phospholipase activity and virulence of pathogenic leptospirae.

Results of investigation of phospholipase activity and virulence of pathogenic leptospirae on a solid nutrient medium using the method of agar layers with 1% of L-lecithin in the medium of the second layer are presented. It has been demonstrated that only one zone of translucent medium is formed around the colonies of pathological leptospirae, which is obviously due to the release of phospholipase A. The examined virulent strains of pathogenic leptospirae were found to exhibit greater phospholipase activity (width of the translucent zones being 5.0 +/- 0.34 mm) than the avirulent strains (width of the zones being 1.5 +/- 0.11 mm).

Agar↗

PubMed1985

Doxycycline prophylaxis for experimental leptospira infection in non-human primates and hamsters.

Doxycycline was effective as a chemoprophylactic agent for experimental Leptospira infection in non-human primates and hamsters. Monkeys injected intraperitoneally with Leptospira bataviae, and receiving only diluent as treatment developed a leptospiremia during the first week and later leptospires were cultured from the cerebrospinal fluid and urine. Monkeys treated daily with oral doxycycline for 10 days beginning one day before infection had a shortened period of detectable leptospiremia, and organisms were never detected in the cerebrospinal fluid or urine. Even an oral dose of doxycycline 2 hours before infection and on day 7 prevented the later infection of the cerebrospinal fluid and urine. In hamsters, doxycycline treatment prevented deaths from acute Leptospira infection and when hamsters were treated daily for 4 or more days, renal infection was prevented. The results of animal studies, the susceptibility of LC0475 and the five other isolates to doxycycline in vitro, and lack of evidence for antibiotic resistance in culture suggests this antibiotic may be useful as a prophylactic drug for high risk groups and an effective treatment for leptospirosis in Thailand.

Animals↗

PubMed1977

Leptospirae: their place in the systematics.

The morphology and electron-microscopic anatomy of Leptospirae, the lack of the presence of leptospiral phages (and probably of bacteriocins), and the absence of phagocytosis as a defence mechanism in leptospirosis, indicate the non-bacteriologie character of this genus. Leptospirae form an evolutionary intermediate bridge between the worlds of bacteria and protozoa. In "Bergey's Manual" they are assigned to the world of bacteria for practical reasons; but it seems to be reasonable to stress more largely the "bacteriological" and "protozoologic" markers of Leptospirae, in the subsequent 9th edition of this Manual.

Bacteria↗

PubMed1983

[The occurrence of antibodies to various Leptospira serotypes in swine in The Netherlands in the period 1975-1980].

A total number of 18.675 sera of pigs were examined for the presence of antibodies to various serotypes of Leptospira in the Netherlands during the period from 1975 to 1980. The study showed an average of 21 per cent of positive serological findings. The distribution of these findings amongst the various serotypes of Leptospira was as follows: L. bratislava 39%; L tarassovi 22%; L. ballum 15% and L. icterohaemorrhagiae 12%. The combined other serotypes scored approximately 12%. The percentage of serologically positive animals having a history of abortion was approximately 23%. 23% up to 1978. In 1979, it fell to 11%, and it increased again to 32% in 1980. The common serotypes of Leptospira in sows which aborted were L. bratislava, L. tarassovi, L. ballum and L. icterohaemorrhagiae. L. pomona, L. australis, L. canicola and L. hardjo were rare but were identified in a few cases. It is recommended that measures should be adopted to prevent the introduction of these serotypes.

Abortion, Veterinary↗

PubMed1981

Correlation of virulence, susceptibility to leptospiricidal activity test mediated by antiserum plus complement and colonial morphology of five lines of a strain of Leptospira interrogans serovar copenhageni.

Correlation of virulence, susceptibility to leptospiricidal activity test mediated by antiserum plus complement (LAT) and colonial morphology was investigated using five lines of Leptospira interrogans serovar copenhageni Shibaura. Line No. 2, a moderately virulent strain, passaged in guinea pigs for 24 successive times caused occasional death of guinea pigs. Leptospiras recovered from deceased animals were characterized by decreased susceptibility to LAT and predominance of hazy colonies upon culture. Leptospiras recovered from surviving guinea pigs were of increased susceptibility to LAT and grew predominantly in non-hazy colonies. Virulent line No. 1 subjected to passage through liquid medium for 20 successive times resulted in a slight decrease in virulence and slight increase in susceptibility to LAT, but the predominance of hazy colonies upon culture was invariable. The other three lines, Nos. 3, 4 and 5 which have been maintained for more than 10 years by passage through different media respectively, were avirulent, susceptible to LAT and produced only non-hazy colonies.

Animals↗

PubMed1994

[An investigation on the distribution of leptospirae interrogans in water and soil in southwest of Yunnan Province].

The conservation of pathogenic leptospirae in water and soil is one of the important problems of geography-epidemiological survey of leptospirosis. We have conducted this investigation by using of filtration-culture isolation method in five counties in the west and southwest of Yunnan during 1988-1992. The results showed that the isolates from samples of water and soil collected between July and September in Menglian and Huaping county were leptospirae biflexa while in the samples of water and soil collected between November and December in three counties, 8 strains of L. interrogans were isolated from the samples of Gengma and Baoshan county. The total positive rate was 3.31% (8/242). The positive rate of water and soil was 2.14% (3/140) and 4.9% (5/102) respectively. Strains obtained in this investigation belong to six serogroups: Icterohaemorrhagiae and Pyrogenes in 2 respectively. Canicola, Grippotyphosa, Sejroe and Australis in 1 respectively. These serogroups of leptospirae obtained from water and soil were corresponded with the serogroups obtained from the patients and animals with leptospirosis in local area. This survey provided new data for expounding the structure of the focus of leptospirosis.

China↗

PubMed1994

[Occurrence of Leptospira serovars in old foci of leptospirosis].

In two old natural foci of leptospiroses in an Eastern Slovakian area an epidemiological investigation was made to detect persisting carriership in basis reservoirs-small mammals and the contact with leptospirae in population groups with an occupational risk. Using the microagglutination reaction (MAR), the authors examined 1,106 small mammals and detected in 50 cases, i.e. 4.5%, the presence of specific antibodies against leptospirae, most frequently in species Apodemus agrarius and Ap. flavicollis. Only in one instance a positive reaction was found in the main reservoir--Microtus arvalis. As to serovars, Leptospira grippotyphosa and the group L. sejroe dominated. Of 1,740 examined human sera (832 men, 908 women) 56 samples (3.2%) reacted in MAR (4.1% men, 2.4% women). The spectrum of serovars in positive subjects was the same as in the above mentioned reservoirs with a predominance of L. grippotyphosa and group L. sejroe. As compared with previous examinations made 18 years ago in small mammals, a decline of positivity to almost half was recorded (from 7.8% to 4.5%), a reduction of the number of serovars from 7 to 4 was observed, however, the positivity of dominating serovars did not decline. In humans a higher percentage of positivity to specific antibodies was found, as compared with the past, i.e. 3.0% as compared with 2.0%. The authors found differences in the frequency of different serovars. In the past serovar L. bratislava dominated in the above area, followed by L. grippotyphosa. At present the first place was held by L. grippotyphosa and the group of L. sejroe.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Isolation of Leptospira interrogans serovar grippotyphosa from the skin of a dog.

Leptospira interrogans serovar grippotyphosa was isolated from the skin of a 14-year-old male dog with deteriorating health. Necropsy revealed numerous lesions characteristic of aged dogs, but no evidence of acute hepatitis or nephritis, which are common features of pathogenic Leptospira infections. Antibody to Leptospira was not detected in the dog's serum by microagglutination. Leptospires grew slowly in Barbour-Stoenner-Kelly medium, a medium commonly used to isolate Borrelia, but then grew abundantly in Tween 80-bovine albumin leptospire medium. The isolate was pathogenic to a hamster and was identified by microagglutination and restriction endonuclease analysis.

Animals↗

PubMed1978

Inhibition of leptospiral agglutination by the nondialyzable delipidized serovar-specific main antigens of leptospiras.

Microscopic agglutination of leptospiras was inhibited by the homologous nondialyzable delipidized serovar-specific main (NDTM) antigens of leptospiras. The agglutination was not inhibited by the heterologous NDTM antigens. The results may indicate that the substance participating in the microscopic agglutination of leptospiras with antiserum is the NDTM antigens.

Agglutination↗

PubMed1977

Leptospirosis among dairy workers in the valley of Jezreel: first recorded isolation of Leptospira hardjo in Israel.

Five cases of leptospirosis among dairy farmers in the Valley of Jezreel are described. The disease was caused by leptospirae of serotype hardjo and available epidemiological evidence suggested infection due to contact with cows. This is the first time that Leptospira hardjo has been isolated and identified in Israel. Infection with L. hardjo should be regarded as a significant occupational risk and this strain should be included in the group of antigens used for screening sera for leptospira antibodies in Israel.

Animals↗

PubMed1977

Isolation of serotype hardjo and other leptospirae from armadillos in Argentina.

A serologic, bacteriologic, and histopathologic examination for leptospires was carried out on 89 armadillos (Chaetophractus villosus) from Argentina. Forty-seven per cent of the serum samples yielded positive results when tested by microscopic-agglutination. Predominant agglutination reactions were to the Hebdomadis and Bataviae serogroups. A total of 15 Leptospira isolations (from 16.8 per cent of the animals tested) were obtained from kidney tisse. Nine of the isolates were identified as belonging to the Bataviae group serotypes argentiniensis, paidjan, or bataviae; three other isolates proved to be the Canicola group serotype canicola; two others were Leptospira biflexa strains; and the last isolate was found to be serotype hardjo of the Hebdomadis group. The latter finding represents the first isolation of serotype hardjo from this animal species. Histopathologic examination of kidneys from 11 of the animals yielding pathogenic leptospires permitted a diagnosis of interstitial nephritis. This intersitial nephritis, presenting the characteristic picture of lymphoid infiltration, appeared intense in two animals, moderate in five others, and only slight in the remaining four. These histopathologic findings of chronic nephritis, combined with the high positive serologic and cultural isolation rates, suggest that the armadillo is an important natural reservoir-host for pathogenic leptospirae.

Animals↗

PubMed1998

[Analysis of genomic polymorphism in leptospira by polymerase chain reaction with random primers].

A test system for genetic typing of Leptospirae is developed, based on the polymerase chain reaction (PCR) with arbitrary primers. Thirteen strains of 4 Leptospira species were examined: L. interrogans, L. parva, L. illini, and L. inadai. Analysis of polymorphism of amplicon length (PAL) by the PCR with short Sh1 and Sh2 primers revealed genotypical differences at the inter- and intraspecias levels, as well as at the subserovar level. PAL of L. interrogans strains Rga and M-20, serovars icterohaemorrhagiae and copenhageni, were identical both with Sh1 and Sh2 primers. Moreover, PCR with Sh2 primer showed genotypical similarity between strains Moscow V and M. oeconomus, serovar grippotyphosa of the same serogroup. Analysis of PAL by the PCR with long Lgn1 and Lgn2 primers showed similar results. Analysis of the PAL values obtained by the PCR with all primers permitted us to differentiate 9 L. interrogans strains into 8 PAL genotypes and identify a different degree of genotypical relation between strains of different serovars of this species. Complete genotypical relationship between strains L. inadai N 10 and EMJH 86 (serovar lyme) was confirmed by the new test system. Therefore, PCR-based test system with different primers can be used to differentiate between closely related Leptospira strains and to investigate the genotypical relationships between the strains at the intra- and interspecies and inter- and subserovar levels.

DNA Primers↗

PubMedDate not supplied

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

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.

Animals↗

PubMed2026

Genomic and ecological systems-thinking framework for pathogenic Leptospira in Puerto Rico.

INTRODUCTION: Leptospirosis is a complex zoonotic disease requiring high-resolution surveillance. A systems-thinking framework was used to connect genomic and ecological data and map the geographic and host-based structuring of co-circulating pathogenic Leptospira lineages in Puerto Rico. METHODS: Forty-four core genomes of L. interrogans, L. borgpetersenii, and L. kirschneri from human, domestic, and wildlife hosts were analyzed. Spatiotemporal and landscape metadata were integrated using root-to-tip regression, isolation-by-distance profiling and calibrated single-nucleotide polymorphism (SNP) thresholds (≤1, ≤5, and ≤10 SNPs) to define transmission clusters. RESULTS: Leptospira species exhibited distinct ecological pathways partitioned by geography, explaining 56% of genomic variance for L. interrogans and 91% for L. borgpetersenii (PERMANOVA). L. interrogans displayed high landscape connectivity across multiple hosts, forming localized networks (≤1 to ≤10 SNPs) that capture active spillovers (human-to-rat linkages at ≤1 SNP) and resolved into rodent host-specific lineages (R2 = 0.34). Conversely, L. borgpetersenii showed spatial and temporal genomic homogeneity and a lack of host-associated structure within an unpartitioned transmission pool dominated by Mus musculus. As a result, fixed genomic thresholds yielded disparate outcomes: L. interrogans resolved into 4 to 5 discrete, expanding clusters, whereas L. borgpetersenii grouped into a single uniform population at the ≤10-SNP threshold. CONCLUSION: Co-circulating pathogenic leptospires occupy distinct ecological niches shaped by varying host restriction and environmental persistence. Fixed genomic thresholds lack universal applicability; effective genomic epidemiological surveillance must employ species-specific threshold calibration to accurately map transmission pathways.

Puerto Rico↗

PubMed1964

VIRULENCE-LINKED COLONIAL AND MORPHOLOGICAL VARIATION IN LEPTOSPIRA.

Faine, S. (University of Sydney, Sydney, Australia), and J. van der Hoeden. Virulence-linked colonial and morphological variation in Leptospira. J. Bacteriol. 88:1493-1496. 1964.-Large-colony typical hooked Leptospira icterohaemorrhagiae was virulent for hamsters and guinea pigs. On cultivation, it was gradually replaced by a serologically identical small-colony avirulent straight mutant. The hooked virulent form was selected in vivo.

Animals↗