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Malaria and toxoplasmosis are important public health diseases affecting millions of people and animals each year, and there is a continuing need for new and improved treatments for them. Plants have provided many opportunities for new drug leads in pharmacology. We examined 43 crude extracts from Mongolian plants for their activities against the Plasmodium falciparum 3D7 strain and the Toxoplasma gondii RH strain using a SYBR Green-based fluorescence assay and a fluorescence-based assay, respectively. The potential toxicity of these extracts was also assessed on human foreskin fibroblast cells (HFF) using a cell viability assay. From the initial screenings, 11 and 7 crude extracts were effective against T. gondii and P. falciparum, respectively, at 100 µg/ml concentration (≥ 80% inhibition activity). The 50% cytotoxic concentrations of the extracts were estimated on HFF cells, and their 50% inhibitory concentrations (IC50s) were calculated. According to our lead criteria (selective index, SI; value ≥ 10), six plants (Galatella dahurica leaf + flower, Leonurus deminutus leaf + flower, Oxytropis trichophysa aerial part, Schultzia crinita whole plant, Leontopodium campestre root, Spirea salicifolia aerial part) inhibited P. falciparum growth at IC50 values of 5.99–64.15 µg/ml (SI values: 10.11–17.02). Amaranthus retroflexus root was highly active against T. gondii (IC50, 19.89 µg/ml; SI value, 38). This first observation of the anti-Plasmodium and anti-Toxoplasma activities of Mongolian plant extracts shows them to be interesting potential candidates for drug discovery.

Dermacentor nuttalli is the most commonly distributed tick species in Mongolia, and responsible for huge economic losses related to tick-borne diseases in livestock industry. Many rural herders have used plants to control tick which is noted in few documents, mostly transferred orally through generations. The aim of the present study was to determine acaricidal activity of Mongolian plants against D. nuttalli. We checked acaricidal activity of 113 crude extracts of 76 plant species included in 26 families. Among them Amaranthus retroflexus root (40%), Ephedra sinica leaf (40%), Erigeron acer root (40%), Ranunculus japonicus root (42%), and Spiraea salicifolia leaf (43.5%) showed potential activity against D. nuttalli. Acaricidal activity of Mongolian plants were experimented in vitro condition in first time. Furthermore, the study will continue isolation and identification active ingredients of potential candidates. We hope this study will be start line of acaricidal activity research in our country. Монгол орны ургамлын Акарицид (хачиг үхүүлэх) идэвхийн судалгаа Монгол орны бүх бүс нутагт Dermacentor nuttalli зүйл хачиг өргөн тархсан төдийгүй мал аж ахуйд хамгийн их хор хөнөөл учруулдаг. Малчид хачиг, шавжтай тэмцэхэд зарим ургамлыг ханд, цацлага, утлага хэлбэрээр хэрэглэж ирсэн уламжлалтай ч түүний шинжлэх ухааны үндэслэлтэй эсэхийг тогтоох судалгаа төдийлөн хийгдээгүй байна. Бид энэ удаа D. nuttalli хачиг дээр турших цуврал судалгааны ажлыг эхлүүлэх зорилго тавин ажиллав. Нийт 26 овогт хамаарагдах 76 зүйл ургамлын 113 дээж дээр акарицид идэвхийг шалгахад, тэдгээрээс Урвуу гагадайн (Amaranthus retroflexus) үндэс, Нангиад зээргэний (Ephedra sinica) навч, Хахуун цийлэгийн (Erigeron acer) үндэс тус бүр 40%, Япон холтсон цэцгийн (Ranunculus japonicus) үндэс 42%, Бургас навчит тавилганы (Spiraea salicifolia) навч 43.5% буюу бусад ургамлаас илүү идэвх үзүүлж байв. Энэхүү судалгаагаар анх удаа Монгол орны хачиг дээр in vitro орчинд туршин сорих арга зүйг нэвтрүүллээ. Энэ нь цаашид ургамлаас хачгийн эсрэг үйлдэлтэй бодис, нэгдэлийг хайж илрүүлэх, цуврал суурь судалгааны ажлын эхлэл болж өгч байгаагаараа чухал ач холбогдолтой юм. Түлхүүр үг: акарицид (хачиг үхүүлэх) идэвх, хачиг, Dermacentor nuttalli, ургамал

application/pdf, Equine piroplasmosis caused by Theileria equi and Babesia caballi is an economically important disease with a worldwide distribution. The objective of the present study was to investigate the seroepidemiology of T. equi and B. caballi in horses reared in various Mongolian provinces. Serum samples prepared from blood collected from horses in 19 Mongolian provinces were screened for antibodies specific to T. equi and B. caballi using enzyme-linked immunosorbent assays based on recombinant forms of T. equi merozoite antigen-2 and the B. caballi 48-kDa merozoite rhoptry protein, respectively. Of 1,282 horses analyzed, 423 (33%) and 182 (14.2%) were sero-positive for T. equi and B. caballi, respectively. Additionally, 518 (40.4%) were positive for at least 1 parasite species, of which 87 (16.8%) were co-infected with both parasites. Both T. equi and B. caballi were detected in all surveyed provinces, and on a per province basis the positive rates ranged from 19.0 to 74.2% and 4.5 to 39.8%, respectively. Theileria equi- and B. caballi-positive rates were comparable between male horses (31.9 and 14.1%, respectively) and female horses (34.5 and 14.3%, respectively). However, the positive rates were higher in the >3-yr-old age group (37.7 and 15.6%, respectively) compared with the 1-3-yr-old age group (19.4 and 10.0%, respectively). These findings confirmed that T. equi and B. caballi infections are widespread among horses all over Mongolia, and that horse age is a risk factor for infection in this country. Our results will be useful for designing appropriate control measures to minimize T. equi and B. caballi infections among Mongolian horses.

Dourine is an equine protozoan disease caused by Trypanosoma equiperdum. Dourine-afflicted animals die after developing neurological clinical signs, such as unilateral paresis. The disease has been a problem for many years; however, the pathogenesis regarding the neurological clinical signs of dourine has been unclear. In the present study, we conducted a histopathological examination in order to investigate the mechanisms by which dourine-afflicted horses develop the accompanying neurological clinical signs. Four dourine-afflicted horses in Mongolia were evaluated. An apparently healthy horse exhibited multifocal neuritis without axonal or myelin degeneration. The other horses, which had obvious neurological clinical signs, also exhibited multifocal neuritis. In particular, the nerves that innervated areas associated with neurological clinical signs exhibited neuritis with demyelination in the latter horses. Inflamed, non-demyelinating nerves were infiltrated with B lymphocytes and T lymphocytes; while inflamed, demyelinating nerves were infiltrated with mononuclear phagocytes. Our observations revealed lesion progression in the nerves, such that polyradiculoneuropathy could explain the accompanying neurological clinical signs of dourine. To our knowledge, this is the first report to describe a pathogenic mechanism for the development of the neurological clinical signs found in dourine-afflicted horses.

In Mongolia, horses play important roles, not only in livestock production, but also in terms of culture, tradition, and Mongolian beliefs. Although the presence of non-tsetse-transmitted horse trypanosomoses, which are caused by infections with Trypanosoma evansi (surra) and T. equiperdum (dourine), has been reported in the country, whether there is a nationwide epidemic of these infectious diseases is unknown. In the present study, a nationwide surveillance of horse trypanosomoses was performed. The sample sizes for each province, the whole country, and male and female horses were, respectively, 96, 2,400, and 316 and 306. In total, 3,641 samples of horse sera were collected by simple random sampling. The rTeGM6-4r-based ELISA, which was applied for surra against cattle and water buffalo and dourine against horse, revealed that the overall sero-prevalence of the diseases in Mongolia was 4.8%. Among them, high sero-prevalences were observed in the central provinces (5.2–11.0%, p < 0.05) of the country. The sero-prevalence was significantly higher in females than in males (6.0% and 4.0%, p < 0.05, respectively) and in non-castrated males (8.4%, p < 0.01) compared with castrated males (3.0%). These results suggested that currently, horse trypanosomoses are a nationwide endemic problem in Mongolia. Knowledge of the nationwide endemic status of non-tsetse-transmitted horse trypanosomoses in Mongolia will be useful to prevent these diseases.

application/pdf, Mongolia is an agriculturally rich country with large livestock populations that contribute significantly to its national economy. However, the export market for live animals and livestock products is often constrained for various reasons including infectious diseases. Babesia bovis and B. bigemina, which are bovine hemoprotozoan parasites, cause severe forms of clinical babesiosis, in cattle. However, a country-wide survey to determine the exposure rates in various provinces in Mongolia was not conducted to determine the risk for infections with these parasite species. Therefore, we investigated the frequency of antibodies to B. bovis and B. bigemina in cattle reared throughout Mongolia. B. bovis-and B. bigemina-specific enzyme-linked immunosorbent assays (ELISAs) were used to screen the serum samples sourced from 1946 cattle in 19 of 21 provinces and a provincial municipality (Ulaanbaatar) in Mongolia. We found 351 (18.0%) samples positive for B. bovis and 435 (22.4%) samples positive for B. bigemina infections. The B. bovis- and B. bigemina-positive rates ranged from 0.8 to 61.5% and 4.0 to 50.6%, respectively, among the surveyed provinces. The positive rates of B. bovis and B. bigemina infections were relatively higher in the provinces located in northernmost, northern, eastern, southeastern, and southern Mongolia. Additionally, the B. bovis- and B. bigemina-positive rates were not significantly different between females (18.2 and 22.2%, respectively) and males (17.2 and 18.8%, respectively) or between the 1–3-year-old (16.2 and 19.4%, respectively) and >3-year-old (17.1 and 20.9%, respectively) age groups. The differential seropositivity for B. bovis and B. bigemina infections among the provinces may reflect the variations in the risk of cattle being infected with these parasite species. The findings of the present study highlight the need for country-wide control measures, including tick control programs, to minimize the rates of B. bovis and B. bigemina infections in Mongolian cattle. © 2018 Elsevier B.V.

Bovine babesiosis, which is caused by species of genus Babesia, is a leading cause of considerable economic losses to the cattle industry each year. Bovine Babesia species have frequently been detected in non-cattle hosts, such as water buffalo (Bubalus bubalis), from which the parasites can be transmitted by ticks to cattle. Therefore, Babesia infections should be minimized not only in cattle but also in non-cattle carriers. In the present study, we surveyed the Bactrian camels (Camelus bactrianus) in Mongolia for three clinically significant bovine Babesia species, including Babesia bovis, B. bigemina, and Babesia sp. Mymensingh, which had been detected previously in Mongolian cattle. We screened blood DNA samples from 305 Bactrian camels in six Mongolian provinces for these species, using parasite-specific PCR assays. Our findings showed that the Bactrian camels in Mongolia were infected with all three Babesia species surveyed. The overall positive rates of B. bovis, B. bigemina, and Babesia sp. Mymensingh were 32.1%, 21.6%, and 24.3%, respectively, whereas 52.5% of the surveyed animals were infected with at least one parasite species. We also found that the female Bactrian camels and the Mongolian native camel breed had significantly higher Babesia positive rates than the male Bactrian camels and the Hos Zogdort breed. In Mongolia, cattle and Bactrian camels usually share common pasture lands for grazing; furthermore, tick species infesting cattle also infest Bactrian camels. Our findings, together with these observations, suggest that the tick transmission of bovine Babesia species might be possible between cattle and Bactrian camels. Therefore, strategies for the control of bovine babesiosis in Mongolia should include methods to minimize bovine Babesia species infections in Bactrian camels.

application/pdf, 179 compounds in a Mongolian compound library were investigated for their inhibitory effect on the in vitro growth of Plasmodium falciparum and Toxoplasma gondii. Among these compounds, brachangobinan A at a half-maximal inhibition concentration (IC50) of 2.62 μM and a selectivity index (SI) of 27.91; 2-(2′-hydroxy-5′-O-methylphenyl)-5-(2″,5″-dihydroxyphenyl)oxazole (IC50 3.58 μM and SI 24.66); chrysosplenetin (IC50 3.78 μM and SI 15.26); 4,11-di-O-galloylbergenin (IC50 3.87 μM and SI 13.38); and 2-(2′,5′-dihydroxyphenyl)-5-(2″-hydroxyphenyl)oxazole (IC50 6.94 μM and SI 11.48) were identified as potential inhibitors of P. falciparum multiplication. Additionally, tricin (IC50 12.94 μM and SI > 23.40) was identified as a potential inhibitor of T. gondii multiplication. Our findings represent a good starting point for developing novel antimalarial and anti-Toxoplasma therapeutics from Mongolian compounds.

application/pdf, Dourine is caused by Trypanosoma equiperdum via coitus with an infected horse. Although dourine is distributed in Equidae worldwide and is listed as an internationally important animal disease by the World Organization for Animal Health (OIE), no effective treatment strategies have been established. In addition, there are no reports on drug discovery, because no drug screening system exists for this parasite. A new T.?equiperdum strain was recently isolated from the genital organ of a stallion that showed typical symptoms of dourine. In the present study, we adapted T.?equiperdum IVM-t1 from soft agarose media to HMI-9 liquid media to develop a drug screening assay for T.?equiperdum. An intracellular ATP-based luciferase assay using CellTiter-Glo reagent and an intracellular dehydrogenase activity-based colorimetric assay using WTS-8 tetrazolium salt (CCK-8 reagent) were used in order to examine the trypanocidal effects of each compound. In addition, the IC50 values of 4 reference trypanocidal compounds (pentamidine, diminazene, suramin and melarsomine) were evaluated and compared using established assays. The IC50 values of these reference compounds corresponded well to previous studies involving other strains of T. equiperdum. The luciferase assay would be suitable for the mass screening of chemical libraries against T.?equiperdum because it allows for the simple and rapid-evaluation of the trypanocidal activities of test compounds, while a simple, inexpensive colorimetric assay will be applicable in developing countries for the evaluation of the drug sensitivity of epidemic trypanosome strains. c 2017 The Authors

Bovine babesiosis caused by Babesia species is an economically significant disease of cattle. Severe clinical babesiosis in cattle is caused by Babesia bovis, B. bigemina, and the recently discovered Babesia sp. Mymensingh. Mongolia is an agricultural country with a large cattle inventory. Although previous studies have detected active infections of B. bovis and B. bigemina in Mongolian cattle, only a few provinces were surveyed. Additionally, the endemicity of Babesia sp. Mymensingh in Mongolia remains unknown. We screened blood DNA samples from 725 cattle reared in 16 of the 21 Mongolian provinces using B. bovis-, B. bigemina-, and Babesia. sp. Mymensingh-specific PCR assays. The overall positive rates of B. bovis, B. bigemina, and Babesia sp. Mymensingh were 27.9% (n = 202), 23.6% (n = 171), and 5.4% (n = 39), respectively. B. bovis and B. bigemina were detected in cattle in all surveyed provinces; whereas Babesia sp. Mymensingh was detected in 11 of the 16 surveyed provinces. On a per province basis, the B. bovis- B. bigemina-, and Babesia sp. Mymensingh-positive rates were 5.9–52.0%, 9.1–76.3%, and 0–35.7%, respectively. In conclusion, this is the first report of Babesia sp. Mymensingh in Mongolia. In addition, we found that species of Babesia that are capable of causing bovine clinical babesiosis, including B. bovis, B. bigemina, and Babesia sp. Mymensingh, are widespread throughout the country.

Trypanosoma equiperdum primarily parasitizes the genital organs and causes dourine in equidae. We isolated a new T. equiperdum strain, T. equiperdum IVM-t1, from the urogenital tract of a horse definitively diagnosed as having dourine in Mongolia., Trypanosoma equiperdum primarily parasitizes the genital organs and causes dourine in equidae. We isolated a new T. equiperdum strain, T. equiperdum IVM-t1, from the urogenital tract of a horse definitively diagnosed as having dourine in Mongolia. Here, we report the whole-genome sequence, the predicted gene models, and their annotations.

application/pdf, Dourine is a lethal protozoan disease of equids, and it is caused by Trypanosoma equiperdum infection via coitus. To date, treatment strategies against the dourine are not recommended because of the frequent relapses; therefore, the World Organisation for Animal Health recommends the stamping-out policy for the control of dourine. Our previous studies have revealed a number of horses with dourine in Mongolia that is the fifth largest horse-breeding country. It is difficult to apply the stamping-out policy for cases of dourine in Mongolia because of an inadequate livestock guarantee system. Therefore, the development of effective treatment measures is an urgent need. In this study, an 8-year-old stallion was definitely diagnosed with dourine based on clinical signs, molecular analysis, and microscopic examination of trypanosomes. Combination therapy with diminazene aceturate and quinapyramine sulfate was applied. Before the treatment, the characteristic clinical signs of dourine were observed, and trypanosomes were detected in the urogenital tract mucosal swab samples by microscopic examination and polymerase chain reaction (PCR). Moreover, positive serological results were obtained. After the treatment, we observed an improvement in the health of the treated horse and no trypanosome infection in its urogenital tract by microscopic examination and PCR. Moreover, serological tests showed seronegative results. The horse has showed no relapse for at least 2.5 years after the treatment, and its reproductive ability has improved. Our result suggests that trypanosomes did not invade cerebrospinal fluid when we started the therapy. In conclusion, the combination therapy has therapeutic potential against dourine at an early phase.

application/pdf, Anaplasma ovis is a tick-borne obligate intracellular rickettsial bacterium that causes anaplasmosis in domestic and wild small ruminants. Sheep and goats, whose combined population is approximately 48.5-million in Mongolia, play a vital role in the country's economy. In this study, we conducted an epidemiological survey of A. ovis in sheep and goats from 19 of 21 provinces in Mongolia. Additionally, DNA samples extracted from unfed ticks collected in 11 Mongolian provinces were also screened for A. ovis. Of 1179 and 871 blood DNA samples from sheep and goats, 813 (69.0%) and 621 (71.3%), respectively, were positive for A. ovis when screened by a PCR assay based on major surface protein 4 gene (msp4). On a per province basis, A. ovis infection rates ranged from 7.4%–93.3% and 13.3%–100% in sheep and goats, respectively. Subsequently, DNA samples prepared from 721 unfed ticks, including Dermacentor nuttalli (n = 378), Ixodes persulcatus (n = 95), Haemaphysalis pospelovashtromae (n = 120), and Hyalomma asiaticum (n = 128), were screened for A. ovis using the same PCR assay. Although nine D. nuttalli were A. ovis-positive, all other tick DNA samples were negative. In addition to reporting A. ovis in sheep and goats from all over Mongolia, this study identified D. nuttalli as a potential transmission vector of A. ovis in Mongolia. The present data highlight the importance of monitoring Mongolian sheep and goats for possible episodes of clinical anaplasmosis and controlling D. nuttalli throughout the country. © 2018 Elsevier B.V.

Our previous studies report epidemics of non-tsetse-transmitted equine trypanosomosis in Mongolia. However, the current status of non-tsetse-transmitted equine trypanosomosis endemicity remains to be clarified in some parts of Mongolia. We previously reported the potential application of rTeGM6-4r-based diagnostic tools, an rTeGM6-4r-based immunochromatographic test (ICT) and an enzyme-linked immunosorbent assay (ELISA), in the serological surveillance of equine trypanosomosis in Mongolia. In the present study, the utility of the rTeGM6-4r-based ICT was validated. The rTeGM6-4r-based ICT accurately diagnosed positive reference sera that had been prepared from dourine horses in Mongolia, similarly to the rTeGM6-4r-based ELISA. The diagnostic performance of the rTeGM6-4r-based ICT was maintained when the strips were preserved for at least 2 months under dry conditions. The ICT detected 42 positive serum samples from a total of 1701 equine sera that had been collected from all 21 provinces of Mongolia. The κ-value, sensitivity and specificity of rTeGM6-4r-based ICT were 0.58, 50.0% (95% CI, 37.7–62.3%) and 99.3% (95% CI, 98.7–99.6%), respectively, in comparison to the rTeGM6-4r-based ELISA. Our field-friendly rTeGM6-4r-based ICT was found to be useful for the serological diagnosis of non-tsetse-transmitted equine trypanosomosis in rural areas of Mongolia.

application/pdf@@@application/vnd.ms-powerpoint, Babesia microti is a tick-transmitted zoonotic hemoprotozoan parasite. In the present study, we investigated B. microti infection in questing ticks in Mongolia. A total of 219 questing ticks were collected from three different Mongolian provinces (Bayan-Olgii, Khovsgol, and Selenge). Of these, 63 from Selenge were identified as Ixodes persulcatus, while the remaining 156 (from all three provinces) were identified as Dermacentor nuttalli. When the tick DNA samples were screened using a B. microti-specific nested PCR, 19 (30.2%) of the 63 I. persulcatus ticks were found to be B. microti-positive. The parasite was not detected in D. nuttalli. Subsequently, the 18S rRNA, cox1, and tufA sequences of B. microti were amplified, sequenced, and subjected to phylogenetic analyses. Sequencing analyses showed that the Mongolian 18S rRNA, cox1, and tufA sequences were 99.6-100%, 96.7-97.2%, and 94.7-95.3% homologous, respectively, with B. microti R1 strain US-type sequences from humans. In the phylogenetic analyses, the Mongolian cox1 and tufA sequences were found to be separate lineages, which formed sister-clades to the R1 strain sequences, while all of the Mongolian B. microti 18S rRNA sequences were clustered within US-type clade containing several other sequences of human origin. In conclusion, in addition to reporting the presence of B. microti for the first time in questing ticks in Mongolia, the present study found that Mongolian I. persulcatus ticks were infected with US-type B. microti. These findings warrant large-scale studies to detect and characterize B. microti in ticks, small mammals, and humans. Such studies should provide us with a better understanding of zoonotic Babesia epidemiology in Mongolia. c 2015 Elsevier Ireland Ltd.

Tick infestation activity has increased in Mongolia in recent years. Rickettsiosis, ehrlichiosis, Lyme disease and Q fever are all tick borne zoonoses. We aimed to survey dispersal of these zoonotic disease agents in vector tick population by amolecular diagnostic method. In total, 1462 ticks were harbored from various geographical regions of Mongolia. Genomic DNA was extracted from 400 pasture ticks(Dermacentornuttalli, Dermacentordaghestanicus, Hyalommadromedarii, Hyalommaas. asiaticum) and 100 forest ticks (Ixodespersulcatus). PCR was performed to detect zoonotic pathogens and the prevalence of Rickettsia spp., was 12.5 % and 22.9% in pasture and forest tick DNA samples respectively. Ehrlichiaspp., were detected in 28.5 % and 75 % in pasture and forest ticksrespectively. Interestingly, Lyme disease agentBorreliaspp. has not detected in 200 pasture tick DNA samples, but found in one out of 96forest tick DNA samples. Contrary to this, Coxiellaburnetii, the causative agent of Q fever found only in one out of 240 pasture ticksand was not detected in 96 forest tick DNA samples. Results have proven that molecular diagnostic PCR method is the fastest reliable tool to detect zoonotic pathogens in vector ticks.Mongolian Journal of Agricultural Sciences Vol.13(2) 2014:3-7

Anaplasma phagocytophilum is a zoonotic agent of public health importance, infecting both humans and animals. An investigation of the presence of Anaplasma phagocytophilum as well as Anaplasma platys was conducted in a forest area of Selenge province, Mongolia, where ticks are widely distributed and tick-borne diseases are highly endemic. Ticks were collected and tested using polymerase chain reaction based on groEL methodology. Anaplasma phagocytophilum was detected in 14 (6%) of Ixodes persulcatus ticks and four (1%) Dermacentor nuttalli ticks; infection of Anaplasma platys was detected in 1% of Ixodes persulcatus ticks and 10% of Dermacentor nuttalli ticks. The phylogenetic tree showed that the Anaplasma phagocytophilum clustered with the Russian group, most likely due to similar geographical locations. This finding is significant for both veterinary and public health officials given that these agents can cause both animal and human illness.

Anaplasma marginale is an etiologic agent of bovine anaplasmosis. This study aimed to molecularly detect and characterize A. marginale that is prevalent in Mongolian cattle populations. A highly specific and sensitive nested PCR (nPCR) method based on the Msp5 gene was developed to detect A. marginale (Msp5 nPCR). The method detected A. marginale from the positive DNA samples obtained from different countries, while no amplicons were observed from DNA samples of several other bovine blood pathogens tested. The detection limit of Msp5 nPCR was determined to be 2 copies/μl. The method was tested against field blood DNA samples prepared from 300 Mongolian cattle in 2010. Results indicated a prevalence rate of 8.7% (26 of 300). On the other hand, partial DNA fragments of an Anaplasma sp. closely related to A. ovis (with 95.0% identity) were detected using a different nPCR method based on groEL gene. The phylogenetic analyses based on the Msp5, groEL and 16S rRNA genes demonstrated that A. marginale isolates in Mongolia were not divergent from the isolates distributed in other countries. The present study successfully established a new nPCR assay that can detect A. marginale, and reported the first molecular detection and characterization of A. marginale and an Anaplasma sp. closely related to A. ovis in Mongolian cattle populations.

application/pdf, Background: Trypanosoma equiperdum causes dourine via sexual transmission in Equidae. T. equiperdum is classified under the subgenus Trypanozoon along with the T. brucei sspp. and T. evansi; however, the species classification of Trypanozoon remains a controversial topic due to the limited number of T. equiperdum reference strains. In addition, it is possible that some were misclassified T. evansi strains. Thus, there is a strong need for a new T. equiperdum strain directly isolated from the genital mucosa of a horse with a clinically-and parasitologically-confirmed dourine infection. Methods: Trypanosomes isolated from the urethral tract of a stallion with suspected dourine, were directly cultivated using soft agarose media at 37 degrees C in 5 % CO2. For molecular characterization, 18S ribosomal RNA (rRNA) gene, the internal transcribed spacer (ITS) and 8 maxicircle DNA regions were amplified by a PCR and their sequences were determined. To analyze the ratio of the kinetoplastic/akinetoplastic population, the kinetoplasts and the nuclei of trypanosomes were subjected to Hoechst staining and observed by fluorescence microscopy. Results: In addition to the clinical symptoms and the molecular diagnosis, this stallion was definitively diagnosed with dourine by the detection of trypanosomes in the urethral mucosa. These results strongly suggested that the isolated trypanosome was true T. equiperdum. T. equiperdum isolated from the urethral tract was adapted in vitro using soft agarose media. Based on the results of a phylogenetic analysis of 18S rRNA and ITS, this T. equiperdum isolate was classified into the Trypanozoon clade. In a PCR of the maxicircle DNA region, only NADH-dehydrogenase subunits 4 and 5 was amplified. Clear kinetoplasts were observed in most of the T. equiperdum isolates. In contrast, most culture-adapted T. equiperdum were of the akinetoplastic form. Conclusion: We concluded that our isolated trypanosome was the first confirmed case of T. equiperdum in Mongolia and named it "T. equiperdum IVM-t1". T. equiperdum IVM-t1 was well adapted and propagated in soft agarose media, which indicates that this culture method is useful for isolation of T. equiperdum from horses with dourine.

In the present study, we have surveyed the presence of a bovine Theileria protozoan, Theileria orientalis, in Mongolian cattle and engorging tick populations from selected provinces and districts in Mongolia. The percentages of infection in the cattle and ticks ranged from 8.8 to 66.6 and from 3.7 to 73.3, respectively, on a per district basis. The genetic diversity of T. orientalis isolates was also studied, based on the protozoan gene encoding a major piroplasm surface protein (MPSP). At least five genotypes (types 1, 3, 5, 7, and N-3) of T. orientalis were found to be circulating among the Mongolian cattle and tick populations. In particular, types 3 and N-3 were common in most of the districts examined, while a strong geographical relationship among the genotypes was not detected in the present study. This is the first epidemiological report describing the presence of T. orientalis infection in Mongolian cattle.

Human defensins play a fundamental role in the initiation of innate immune responses to some microbial pathogens. In this paper, we show that human alpha-defensin-5 displays a parasiticidal role against Toxoplasma gondii, the causative agent of toxoplasmosis. Exposure of the tachyzoite form of T. gondii to defensin induced aggregation and significantly reduced parasite viability in a concentration-dependent peptide. Pre-incubation of tachyzoites with human alpha-defensin-5 followed by exposure to a mouse embryonal cell line (NIH/3T3) significantly reduced T. gondii infection in these cells. Thus, human alpha-defensin-5 is an innate immune molecule that causes severe toxocity to T. gondii and plays an important role in reducing cellular infection. This is the first report showing that human alpha-defensin-5 causes aggregation, leading to Toxoplasma destruction.

Blood feeding tightly regulates the reproductive cycles of ticks. Vitellogenesis and nutritional signaling are key events in the tick reproductive cycle. Here we report the identification of a GATA factor that is synthesized after a blood meal and acts as a transcriptional activator of vitellogenin (Vg), and the identification of an S6 kinase that is a transcription regulator of the amino acid signaling pathway. Tick GATA mRNA accumulated in the midgut prior to blood feeding. However, translation of GATA was activated by blood feeding because the GATA protein dramatically increased in the fat body of engorged females. RNA interference-mediated knockdown of S6 kinase and GATA factor revealed the involvements of S6 kinase in GATA activation and resulted in a significant inhibition of the major yolk protein vitellogenin in engorged ticks and effectively disrupting egg development after a blood meal. These results indicate that the GATA factor, a specific transcriptional activator of Vg gene, represents an important molecule for the regulation of tick vitellogenesis and reproduction.

We have shown here the identification and characterization of two cyclophilin, cyclophilin A (CyPA) and B (CyPB), from the ixodid tick, Haemaphysalis longicornis . Both CyPA and CyPB contain the conserved peptidyl-prolyl isomerase (PPIase) domain, with CyPA consisting of 188 amino acids and CyPB of 216 amino acids. CyPA and CyPB share 50–67% amino acid sequence identity with the cyclophilins of other organisms, and are found in multiple organs throughout the developmental stages of ixodid ticks. In addition, recombinant CyPA and CyPB exhibited PPIase activity that could be inhibited by the cyclic peptides cyclosporin A (CsA). Silencing of CyPA through RNA interference has led to a significant reduction in the body weight of engorged ticks and their failure to lay eggs, in contrast to CyPB whose silencing did not result in any detectable phenotypic changes. Our results indicate that CyPA represents the major cyclophilin protein in H. longicornis involved in blood ingestion, viability, and oocyte development. This is the first report of cyclophilin proteins from ixodid and argasid ticks.

The purpose of this study was to demonstrate the occurrence of equine piroplasmosis in Mongolia, a country in which the disease occurs epidemically in different climatic conditions. Antibodies to Babesia equi and B. caballi were determined in serum samples of 254 pastured horses in different locations of Mongolia using an enzyme-linked immunosorbent assay with recombinant antigens. One hundred and eighty-five (72.8%) and 102 (40.1%) of all serum samples were positive for B. equi and B. caballi infections, respectively. In addition, 78 (30.7%) samples were positive for both B. equi and B. caballi infections. These results indicate that equine piroplasmosis is widespread in Mongolia. To our knowledge, this is the first report describing an epidemiological study on equine piroplasmosis in different geographic regions in Mongolia.

The cDNA encoding the entire mature hypodermin C (HC) of Hypoderma lineatum was cloned and expressed in Escherichia coli as a glutathione S-transferase fusion protein using pGEX vector. The recombinant HC protein (rHC) was tested by Western blotting to detect antibodies to H. lineatum in cattle. Western blotting with rHC as antigen clearly differentiated between H. lineatum-infested cattle sera and normal cattle sera. Forty-six out of forty-eight serum samples from cattle in Central Mongolia were positive, whereas all 30 serum samples from cows in Hokkaido, Japan, were negative by Western blotting. The result of Western blotting was identical to that of a previously developed enzyme-linked immunosorbent assay. These data demonstrated that Western blotting, with rHC expressed in E. coli, might be a useful method for the diagnosis of cattle hypodermosis.

Vitellogenin (Vg) synthesis, vitellogenesis, is an essential process for the development and reproduction of ticks. Our previous finding led to the hypothesis that target of rapamycin (TOR) pathway is important for vitellogenesis in the hard tick, Haemaphysalis longicornis. The TOR pathway controls cellular activity according to nutrient availability in eukaryotes. TOR, a member of the phosphatidylinositol 3-kinase family, is a central player in this pathway. Here, we present preliminary evidence that H. longicornis TOR (HlTOR) controls vitellogenesis via activation of S6 kinase (S6K) in the fat body. RNA interference (RNAi)-mediated gene silencing of HlTOR was undertaken to elucidate the involvement of HlTOR in the vitellogenesis of the tick. HlTOR-RNAi caused inhibition of S6K phosphorylation in the fat body. HlTOR-RNAi also altered not only the expression levels of GATA mRNA and protein but also the intracellular localisation of GATA in the fat body. The expression levels of Vg mRNA and protein in the fat body of HlTOR-RNAi ticks were significantly lower than those in control ticks. In the pre-ovipositional stage, the ovaries of control ticks had brown oocytes developing, but those of HlTOR-RNAi ticks were white and immature. The haemolymph colour indicated that the amount of Vg was lower in HlTOR-RNAi ticks than in the controls. Furthermore, rapamycin inhibited S6K phosphorylation and reduced the expression levels of Vg mRNA and protein in the fat bodies. Vg proteins were not detected in rapamycin-treated fat bodies in the presence of 20-hydroxyecdysone. These results suggest that HlTOR activity is critical for vitellogenesis stimulated by 20-hydroxyecdysone.

We developed a new nested PCR (nPCR) assay based on the Babesia bigemina apical membrane antigen-1 (AMA-1) gene sequence for parasite-specific detection. The primers were designed to amplify 738-bp and 211-bp fragments of the AMA-1 gene by primary and nested PCRs, respectively. The assay was proven to be specific for the B. bigemina, whereas the previously established SpeI-AvaI nPCR assay amplified not only the target fragment of B. bigemina but also a homologous one from Babesia ovata. The AMA-1 nPCR assay was also evaluated using field DNA samples extracted from 266 bovine blood samples collected from Mongolia in 2010. In a comparative evaluation, 90 (33.8%) and 25 (9.4%) of the blood samples showed positive reactions for B. bigemina by the SpeI-AvaI nPCR and AMA-1 nPCR assays, respectively. The sequencing analysis of the nPCR products confirmed that the AMA-1 nPCR method had specifically detected the target B. bigemina DNA. However, 4 different kinds of sequences were determined among the SpeI-AvaI nPCR amplicons. Two of them were derived from B. bigemina and B. ovata, while the origins of the others were unknown. In the current study, the presence of B. bigemina was clearly demonstrated among Mongolian cattle populations by the current nPCR assay for the first time. Furthermore, our findings also indicate that the AMA-1 nPCR assay may be a useful diagnostic tool for the specific detection of B. bigemina.

We conducted a molecular epidemiological study on Babesia bovis in Mongolia. Three hundred blood samples collected from cattle grazed in seven different districts were initially screened using a previously established diagnostic polymerase chain reaction (PCR) assay for the detection of B. bovis-specific DNA. Positive samples were then used to amplify and sequence the hyper-variable regions of three B. bovis genes encoding the merozoite surface antigen (MSA)-1, MSA-2b, and MSA-2c. The diagnostic PCR assay detected B. bovis among cattle populations of all districts surveyed (4.4–26.0%). Sequences of each of the three genes were highly homologous among the Mongolian isolates, and found in a single phylogenetic cluster. In particular, a separate branch was formed only by the Mongolian isolates in the MSA-2b gene-based phylogenetic tree. Our findings indicate that effective preventative and control strategies are essential to control B. bovis infection in Mongolian cattle populations, and suggest that a careful approach must be adopted when using immunization techniques.

Toxoplasma gondii and Neospora caninum are closely related apicomplexan parasites. The surface antigen 1 of T. gondii (TgSAG1) is a major immunodominant antigen and, therefore, is considered to be a good candidate for the development of an effective recombinant vaccine against toxoplasmosis. In this study, N. caninum stably expressing the TgSAG1 gene (Nc/TgSAG1) was constructed using pyrimethamine-resistant DHFR-TS and GFP genes as double-selection markers. The expression level, molecular weight, and antigenic property of recombinant TgSAG1 expressed by the Nc/TgSAG1 were similar to those of the native TgSAG1. The mice immunized with Nc/TgSAG1 induced TgSAG1-specific Th1-dominant immune responses and protected the mice from a lethal challenge infection with T. gondii. These results indicate that N. caninum may provide a new tool for the production of a live recombinant vector vaccine against toxoplasmosis in animals. To our knowledge, this is the first report to evaluate the usefulness of N. caninum-based live vaccine.

A full-length cDNA-encoding lysozyme was obtained from cDNA libraries of salivary glands of the hard tick Haemaphysalis longicornis and designated as HlLysozyme. The HlLysozyme sequence represents an open reading frame for a putative signal peptide and the mature protein composed of 121 amino acids. The calculated molecular weight of the protein is 13.7 kDa, and the theoretical isoelectric point is 9.85. HlLysozyme shares 41–79% amino acid sequence identity with the lysozymes of other organisms. The activity of recombinant HlLysozyme expressed in Escherichia coli was confirmed by a lytic zone assay using lyophilized Micrococcus lysodeikticus. The HlLysozyme activity decreased at 70 °C and was demonstrated at acidic side and neutral in a pH range. Elevated gene expression of HlLysozyme was observed when female ticks were challenged with bacteria, suggesting possible roles of lysozyme as an innate immunity of ticks against microorganisms.

Ticks are long-lived hematophagous arthropods and have tolerance to starvation. They can survive without food during the host-seeking period for several months to years. To understand how ticks obtain energy over a long period of non-feeding (starvation), we focused on autophagy, a crucial proteolysis system via the lysosomes for various cellular processes that is induced during starvation in eukaryotes. In the present study, EST databases for several organs of the tick Haemaphysalis longicornis led to the identification of HlATG3, HlATG4 and HlATG8, homologues of 3 autophagy-related (ATG) genes, ATG3, ATG4 and ATG8/LC3/GABARAP, respectively, which are essential for the Atg8 conjugation system in model animals. Real-time PCR results revealed that the expression of HlATG3, HlATG4 and HlATG8 in the tick showed higher levels during the non-feeding period than the feeding period, suggesting that the Atg8 conjugation system is at work in unfed ticks. Notably, their expression levels were higher in the midgut, a digestive organ, of unfed than fed adults. Histological analysis demonstrated that lipids and glycogen accumulated within the epithelial cells of the midgut in unfed ticks, implying that the midgut of unfed ticks serves as storage of those components as nutrients during non-feeding. Furthermore, autophagic organelles were found in the midgut undifferentiated cells of unfed ticks. The starved condition appears to be associated with the increased expression of HlATG genes in the midgut of unfed ticks. Tick autophagy might help compensate for the loss of nutrients derived from host blood components during the non-feeding period.

Longicin, a defensin-like peptide, was recently identified in the hard tick Haemaphysalis longicornis. Longicin and one of its synthetic partial analogs (P4) displayed antimicrobial/fungicidal/parasiticidal activity. In the present study, we compared longicin-derived synthetic analogs in order to characterize the antimicrobial motif (P4) by analyzing some structural features using various bioinformatic tools and/or CD spectroscopy. According to the chemicophysical characteristics, P4 is suggested to be a cationic peptide with hydrophobic and amphipathic character. The predicted secondary structure indicated the existence of a beta-sheet, which was also observed in the modeled tertiary structure. CD spectroscopic results also showed the existence of a beta-sheet and transition to a helical conformation in the presence of membrane-mimicking conditions. These structural observations on P4 suggested that the antimicrobial activity could be due to the beta-sheet as well as the alpha-helix. In addition, a sequence homology search showed that molecules identified in other ticks and organisms also have the P4 analogous domain at their C-terminal, which indicates P4 as a conserved domain. The peptide P4 also showed low cytolytic activity. Based on the present result and previously reported studies, the peptide P4 could be suggested as a novel antimicrobial domain indicating future therapeutic agent against bacteria.

Background Lysine-ketoglutarate reductase/saccharopine dehydrogenase (LKR/SDH) is a bifunctional enzyme catalyzing the first two steps of lysine catabolism in plants and mammals. However, to date, the properties of the lysine degradation pathway and biological functions of LKR/SDH have been very little described in arthropods such as ticks. Methodology/Principal Findings We isolated and characterized the gene encoding lysine-ketoglutarate reductase (LKR, EC 1.5.1.8) and saccharopine dehydrogenase (SDH, EC 1.5.1.9) from a tick, Haemaphysalis longicornis, cDNA library that encodes a bifunctional polypeptide bearing domains similar to the plant and mammalian LKR/SDH enzymes. Expression of LKR/SDH was detected in all developmental stages, indicating an important role throughout the tick life cycle, including a long period of starvation after detachment from the host. The LKR/SDH mRNA transcripts were more abundant in unfed and starved ticks than in fed and engorged ticks, suggesting that tick LKR/SDH are important for the starved tick. Gene silencing of LKR/SDH by RNAi indicated that the tick LKR/SDH plays an integral role in the osmotic regulation of water balance and development of eggs in ovary of engorged females. Conclusions/Significance Transcription analysis and gene silencing of LKR/SDH indicated that tick LKR/SDH enzyme plays not only important roles in egg production, reproduction and development of the tick, but also in carbon, nitrogen and water balance, crucial physiological processes for the survival of ticks. This is the first report on the role of LKR/SDH in osmotic regulation in animals including vertebrate and arthropods.

A complementary DNA coding a novel kynurenine aminotransferase (KAT) molecule from Haemaphysalis longicornis tick embryo was cloned and characterized. The transcription of the HlKAT occurs at all stages during tick development as well as in the midgut, salivary glands, ovary, and synganglion of adult ticks, and protein expression levels increased during the blood-feeding course. The HlKAT gene without signal peptide was successfully expressed as a glutathione S-transferase fusion protein in soluble form, which is capable of catalyzing the transamination of kynurenine and 3-hydroxykynurenine to kynurenic acid and xanthurenic acid, respectively. The purified recombinant HlKAT showed dose-dependent inhibition effect on the growth of equine babesial parasite, Babesia caballi, in in vitro culture. All results suggested that a specific HlKAT is present in tick and HlKAT may play an important physiological role in H. longicornis. This is the first report of a member enzyme of tryptophan pathway in Chelicerata.

SUMMARYThe dense granule antigen 4 (GRA4) is known as an immundominant antigen ofToxoplasma gondiiand, therefore, is considered as a vaccine candidate. For further evaluation of its vaccine effect, a recombinant plasmid and vaccinia virus, both expressing GRA4, were constructed, and a heterologous prime-boost vaccination regime was performed in a mouse model. The mice immunized with the heterologous prime-boost vaccination regime showed a high level of specific antibody response against GRA4 and a significantly high level of gamma interferon (IFN-γ) production and survived completely against a subsequent challenge infection with a lethal dose ofT. gondii. In addition, the formation of cysts was inhibited in the mice vaccinated with the heterologous prime-boost vaccination regime. These results demonstrate that the heterologous prime-boost vaccination regime using DNA and a vaccinia virus, both expressing GRA4, could induce both humoral and cellular immune responses and provide effective protection against lethal acute and chronicT. gondiiinfections in mice.

Cats are pivotal in the transmission of Toxoplasma gondii. To develop a sensitive and specific serodiagnostic method for feline toxoplasmosis, surface antigen 2 (SAG2) of T. gondii was expressed in Escherichia coli and its diagnostic potential evaluated in an enzyme-linked immunosorbent assay (ELISA). The ELISA with recombinant SAG2 (rSAG2) was able to differentiate very clearly between sera from cats experimentally infected with T. gondii and sera from normal cats. Serum samples collected from domestic cats in Japan were investigated by the ELISA, and the results were compared with those of a commercially available latex agglutination test (LAT) kit. Of the 192 samples screened, 42 (21.9%) were positive by ELISA. Among the 42 ELISA-positive samples, 39 were positive by LAT. There was a significant correlation between ELISA and LAT titers. All the 150 ELISA-negative samples were negative by LAT. These results indicate that the ELISA with rSAG2 expressed in E. coli should be a useful method for detection of T. gondii infection in cats.