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8 pages,2 figures and 2 tables ; [Background] The cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant B. microplus Bm86 protective antigen has been shown to protect cattle against tick infestations. Recently, the gene coding for B. annulatus Bm86 ortholog, Ba86, was cloned and the recombinant protein was secreted and purified from the yeast Pichia pastoris. ; [Results] Recombinant Ba86 (Israel strain) was used to immunize cattle to test its efficacy for the control of B. annulatus (Mercedes, Texas, USA strain) and B. microplus (Susceptible, Mexico strain) infestations. Bm86 (Gavac and Mozambique strain) and adjuvant/saline were used as positive and negative controls, respectively. Vaccination with Ba86 reduced tick infestations (71% and 40%), weight (8% and 15%), oviposition (22% and 5%) and egg fertility (25% and 50%) for B. annulatus and B. microplus, respectively. The efficacy of both Ba86 and Bm86 was higher for B. annulatus than for B. microplus. The efficacy of Ba86 was higher for B. annulatus (83.0%) than for B. microplus (71.5%). The efficacy of Bm86 (Gavac; 85.2%) but not Bm86 (Mozambique strain; 70.4%) was higher than that of Ba86 (71.5%) on B. microplus. However, the efficacy of Bm86 (both Gavac and Mozambique strain; 99.6%) was higher than that of Ba86 (83.0%) on B. annulatus. ; [Conclusion] These experiments showed the efficacy of recombinant Ba86 for the control of B. annulatus and B. microplus infestations in cattle and suggested that physiological differences between B. microplus and B. annulatus and those encoded in the sequence of Bm86 orthologs may be responsible for the differences in susceptibility of these tick species to Bm86 vaccines. ; This work was supported by the Wellcome Trust under the Animal Health in the Developing World initiative through project 0757990 entitled "Adapting recombinant anti-tick vaccines to livestock in Africa" and the Consejería de Educación y Ciencia, JCCM, Spain (project PAI06-0046-5285) and was facilitated through the Integrated Consortium on Ticks and Tick-borne Diseases (ICTTD-3), financed by the International Cooperation Program of the European Union, coordination action project No. 510561. ; Peer reviewed

[Background] Bovine anaplasmosis has been reported in several European countries, but the vector competency of tick species for Anaplasma marginale from these localities has not been determined. Because of the wide distributional range of Dermacentor reticulatus within Europe and the major role of Dermacentor spp. as a vector of A. marginale in the United States, we tested the vector competency of D. reticulatus for A. marginale. ; [Results] Male D. reticulatus were allowed to feed for 7 days on a calf persistently infected with a Zaria isolate of A. marginale, after which they were removed and held off-host for 7 days. The ticks were then allowed to feed a second time for 7 days on a susceptible tick-naïve calf. Infection of calf No. 4291 was detected 20 days post exposure (p.i.) and confirmed by msp4 PCR. Thirty percent of the dissected acquisition fed ticks was infected. In addition, A. marginale colonies were detected by light microscopy in the salivary glands of the acquisition fed ticks. Transmission of A. marginale to calf No. 9191 was confirmed by examination of Giemsa-stained blood smears and msp4 PCR. Ticks were dissected after transmission feeding and presence of A. marginale was confirmed in 18.5% of the dissected ticks. ; [Conclusion] This study demonstrates that D. reticulatus males are competent vectors of A. marginale. Further studies are needed to confirm the vector competency of D. reticulatus for other A. marginale strains from geographic areas in Europe. ; This research was supported by grants from the European Community, INCO-DEV program (project No. 003713), entitled 'Epidemiology and new generation vaccines for Ehrlichia and Anaplasma infections of ruminants', the Junta de Comunidades de Castilla-La Mancha, Spain (project 06036-00 ICSJCCM), entitled "Epidemiología de zoonosis transmitidas por garrapatas en Castilla–La Mancha" and was facilitated through the Integrated Consortium on Ticks and Tick-borne Diseases (ICTTD-3), financed by the International Cooperation Program of the European Union, coordination action project No. 510561. ; Peer reviewed

34 pages, 3 figures, 3 tables, 2 additional files.-- et al. ; [Background]: Bovine anaplasmosis, caused by the rickettsial tick-borne pathogen Anaplasma marginale (Rickettsiales: Anaplasmataceae), is vectored by Rhipicephalus (Boophilus) microplus in many tropical and subtropical regions of the world. A. marginale undergoes a complex developmental cycle in ticks which results in infection of salivary glands from where the pathogen is transmitted to cattle. In previous studies, we reported modification of gene expression in Dermacentor variabilis and cultured Ixodes scapularis tick cells in response to infection with A. marginale. In these studies, we extended these findings by use of a functional genomics approach to identify genes differentially expressed in R. microplus male salivary glands in response to A. marginale infection. Additionally, a R. microplus-derived cell line, BME26, was used for the first time to also study tick cell gene expression in response to A. marginale infection. ; [Results]: Suppression subtractive hybridization libraries were constructed from infected and uninfected ticks and used to identify genes differentially expressed in male R. microplus salivary glands infected with A. marginale. A total of 279 ESTs were identified as candidate differentially expressed genes. Of these, five genes encoding for putative histamine-binding protein (22Hbp), von Willebrand factor (94Will), flagelliform silk protein (100Silk), Kunitz-like protease inhibitor precursor (108Kunz) and proline-rich protein BstNI subfamily 3 precursor (7BstNI3) were confirmed by real-time RT-PCR to be down-regulated in tick salivary glands infected with A. marginale. The impact of selected tick genes on A. marginale infections in tick salivary glands and BME26 cells was characterized by RNA interference. Silencing of the gene encoding for putative flagelliform silk protein (100Silk) resulted in reduced A. marginale infection in both tick salivary glands and cultured BME26 cells, while silencing of the gene encoding for subolesin (4D8) significantly reduced infection only in cultured BME26 cells. The knockdown of the gene encoding for putative metallothionein (93Meth), significantly up-regulated in infected cultured BME26 cells, resulted in higher A. marginale infection levels in tick cells. ; [Conclusions]: Characterization of differential gene expression in salivary glands of R. microplus in response to A. marginale infection expands our understanding of the molecular mechanisms at the tick-pathogen interface. Functional studies suggested that differentially expressed genes encoding for subolesin, putative von Willebrand factor and flagelliform silk protein could play a role in A. marginale infection and multiplication in ticks. These tick genes found to be functionally relevant for tick-pathogen interactions will likely be candidates for development of vaccines designed for control of both ticks and tick-borne pathogens. ; This research was supported by grants from the European Community, INCO-DEV program (project no. 003713), entitled 'Epidemiology and new generation vaccines for Ehrlichia and Anaplasma infections of ruminants', the Ministerio de Ciencia e Innovación, Spain (project BFU2008-01244/BMC), the CSIC intramural project 200830I249 to JF, FAPESP (Fundação de Amparo a Pesquisa do Estado de São Paulo, Brazil), and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil) and was facilitated through the Integrated Consortium on Ticks and Tick-borne Diseases (ICTTD-3), financed by the International Cooperation Program of the European Union, coordination action project No. 510561. ; Peer reviewed

Distinct pathogenic and epidemiological features underlie different Theileria parva strains resulting in different clinical manifestations of East Coast Fever and Corridor Disease in susceptible cattle. Unclear delineation of these strains limits the control of these diseases in endemic areas. Hence, an accurate characterization of strains can improve the treatment and prevention approaches as well as investigate their origin. Here, we describe a set of single nucleotide polymorphisms (SNPs) based on 13 near-complete mitogenomes of T. parva strains originating from East and Southern Africa, including the live vaccine stock strains. We identified 11 SNPs that are non-preferentially distributed within the coding and non-coding regions, all of which are synonymous except for two within the cytochrome b gene of buffalo-derived strains. Our analysis ascertains haplotype-specific mutations that segregate the different vaccine and the buffalo-derived strains except T. parva-Muguga and Serengeti-transformed strains suggesting a shared lineage between the latter two vaccine strains. Phylogenetic analyses including the mitogenomes of other Theileria species: T. annulata, T. taurotragi, and T. lestoquardi, with the latter two sequenced in this study for the first time, were congruent with nuclear-encoded genes. Importantly, we describe seven T. parva haplotypes characterized by synonymous SNPs and parsimony-informative characters with the other three transforming species mitogenomes. We anticipate that tracking T. parva mitochondrial haplotypes from this study will provide insight into the parasite's epidemiological dynamics and underpin current control efforts. ; Table S1: Amplification and sequencing primer sequences, Table S2: Summary of NGS reads (SRA accession number: DRA000613) mapped to T. parva Muguga-mitochondrial sequence (AB499089). ; The Deutsche Forschungsgemeinschaft (DFG); the Kenyan government through the National Research Fund (NRF) and the Germany Academic Exchange Service (DAAD); the Federal Ministry of ...

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License. ; The cattle ticks, Rhipicephalus (Boophilus) spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant Rhipicephalus microplus Bm86 antigen has been shown to protect cattle against tick infestations. However, variable efficacy of Bm86-based vaccines against geographic tick strains has encouraged the research for additional tick-protective antigens. Herein, we describe the analysis of R. microplus glutathione-S transferase, ubiquitin (UBQ), selenoprotein W, elongation factor-1 alpha, and subolesin (SUB) complementary DNAs (cDNAs) by RNA interference (RNAi) in R. microplus and Rhipicephalus annulatus. Candidate protective antigens were selected for vaccination experiments based on the effect of gene knockdown on tick mortality, feeding, and fertility. Two cDNA clones encoding for UBQ and SUB were used for cattle vaccination and infestation with R. microplus and R. annulatus. Control groups were immunized with recombinant Bm86 or adjuvant/saline. The highest vaccine efficacy for the control of tick infestations was obtained for Bm86. Although with low immunogenic response, the results with the SUB vaccine encourage further investigations on the use of recombinant subolesin alone or in combination with other antigens for the control of cattle tick infestations. The UBQ peptide showed low immunogenicity, and the results of the vaccination trial were inconclusive to assess the protective efficacy of this antigen. These experiments showed that RNAi could be used for the selection of candidate tick-protective antigens. However, vaccination trials are necessary to evaluate the effect of recombinant antigens in the control of tick infestations, a process that requires efficient recombinant protein production and formulation systems. ; This work was supported by the Wellcome Trust under the Animal Health in the Developing World initiative through project 0757990 entitled "Adapting recombinant anti-tick vaccines to livestock in Africa"; SEP-CONACYT, Mexico (project 25772); FOMIX, Tamaulipas, Mexico (project 73622); INIA, Spain (project FAU2008-00014-00-00); the Consejería de Educación y Ciencia, JCCM, Spain (project PAI06-0046-5285) and was facilitated through the Integrated Consortium on Ticks and Tick-borne Diseases (ICTTD-3), financed by the International Cooperation Program of the European Union, coordination action project no. 510561. M. Villar was funded by the JAE-DOC program (CSIC-FSE), Spain. ; Peer Reviewed

12 pages, 5 figures.-- PMID: 19243585 [PubMed].-- PMCID: PMC2656471.-- Supporting information (Microsatellite genotypes of individual tick crosses, XLS file) available at: http://www.biomedcentral.com/content/supplementary/1471-2148-9-46-s1.xls.-- et al. ; [Background]: The cattle tick, Rhipicephalus (Boophilus) microplus, economically impact cattle industry in tropical and subtropical regions of the world. The morphological and genetic differences among R. microplus strains have been documented in the literature, suggesting that biogeographical and ecological separation may have resulted in boophilid ticks from America/Africa and those from Australia being different species. To test the hypothesis of the presence of different boophilid species, herein we performed a series of experiments to characterize the reproductive performance of crosses between R. microplus from Australia, Africa and America and the genetic diversity of strains from Australia, Asia, Africa and America. ; [Results]: The results showed that the crosses between Australian and Argentinean or Mozambican strains of boophilid ticks are infertile while crosses between Argentinean and Mozambican strains are fertile. These results showed that tick strains from Africa (Mozambique) and America (Argentina) are the same species, while ticks from Australia may actually represent a separate species. The genetic analysis of mitochondrial 12S and 16S rDNA and microsatellite loci were not conclusive when taken separately, but provided evidence that Australian tick strains were genetically different from Asian, African and American strains. ; [Conclusion]: The results reported herein support the hypothesis that at least two different species share the name R. microplus. These species could be redefined as R. microplus (Canestrini, 1887) (for American and African strains) and probably the old R. australis Fuller, 1899 (for Australian strains), which needs to be redescribed. However, experiments with a larger number of tick strains from different geographic locations are needed to corroborate these results. ; This work was supported by ICTTD-3, financed by the International Cooperation Program of the European Union, coordination action project No. 510561, the Consejería de Educación y Ciencia, JCCM, Spain (project PAI06-0046-5285) (to JF), the Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (to MBL), the Consejo Nacional de Investigaciones Cientícas y Técnicas de Argentina (PIP 2058) and INTA Rafaela (TCP 426100) (to AJM, AAG and CT). V. Naranjo was funded by Junta de Comunidades de Castilla–La Mancha (JCCM), Spain. ; Peer reviewed

[Background] Rhipicephalus (Boophilus) spp. ticks economically impact on cattle production in Africa and other tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The R. microplus Bm86 protective antigen has been produced by recombinant DNA technology and shown to protect cattle against tick infestations. ; [Results] In this study, the genes for Bm86 (R. microplus), Ba86 (R. annulatus) and Bd86 (R. decoloratus) were cloned and characterized from African or Asian tick strains and the recombinant proteins were secreted and purified from P. pastoris. The secretion of recombinant Bm86 ortholog proteins in P. pastoris allowed for a simple purification process rendering a final product with high recovery (35–42%) and purity (80–85%) and likely to result in a more reproducible conformation closely resembling the native protein. Rabbit immunization experiments with recombinant proteins showed immune cross-reactivity between Bm86 ortholog proteins. ; [Conclusion] These experiments support the development and testing of vaccines containing recombinant Bm86, Ba86 and Bd86 secreted in P. pastoris for the control of tick infestations in Africa. ; This work was supported by the Wellcome Trust under the Animal Health in the Developing World initiative through project 0757990 entitled "Adapting recombinant anti-tick vaccines to livestock in Africa" and the Consejería de Educación y Ciencia, JCCM, Spain (project PAI06-0046-5285) and was facilitated through the Integrated Consortium on Ticks and Tick-borne Diseases (ICTTD-3), financed by the International Cooperation Program of the European Union, coordination action project No. 510561. V. Naranjo was funded by Junta de Comunidades de Castilla–La Mancha (JCCM), Spain. ; Peer reviewed

In April 2008, whole blood samples were collected from 36 dromedary camels in Sokoto, Northwestern Nigeria. Following PCR and reverse line blotting, twenty-two samples (61%) resulted positive for Ehrlichia/Anaplasma spp. and three (8%) for Theileria/Babesia spp., with three (8%) cases of co-infections being found. Both sequence and BLAST analyses identified Ehrlichia/Anaplasma spp. and Theileria/Babesia spp. positive cases as Anaplasma platys and Theileria ovis, respectively. This is the first report of the detection of A. platys and T. ovis in camels from sub-Saharan Africa. The epidemiological relevance of this finding is enhanced by the close living of these animals with both dogs and small ruminants. The high prevalence detected for A. platys suggests a possible role of camels as carriers of this infection. ; The UK Department for International Development (DFID) under the umbrella of the 'Stamp Out Sleeping Sickness (SOS) Programme', the UK's Biotechnology and Biological Sciences Research Council (BBSRC) under the 'Combating Infectious Diseases in Live-stock for International Development' (CIDLID) scheme, and the European Union's Seventh Framework Program (FP7/2007-2013) under grant agreement no 221948, Integrated Control of Neglected Zoonoses (ICONZ). ; http://www.elsevier.com/locate/vetpar ; hb2017 ; Veterinary Tropical Diseases

12 pages, 5 figures, 3 tables.-- et al. ; [Background]: Ticks (Acari: Ixodidae) are vectors of pathogens worldwide that cause diseases in humans and animals. Ticks and pathogens have co-evolved molecular mechanisms that contribute to their mutual development and survival. Subolesin was discovered as a tick protective antigen and was subsequently shown to be similar in structure and function to akirins, an evolutionarily conserved group of proteins in insects and vertebrates that controls NF-kB-dependent and independent expression of innate immune response genes. The objective of this study was to investigate subolesin expression in several tick species infected with a variety of pathogens and to determine the effect of subolesin gene knockdown on pathogen infection. In the first experiment, subolesin expression was characterized in ticks experimentally infected with the cattle pathogen, Anaplasma marginale. Subolesin expression was then characterized in questing or feeding adult ticks confirmed to be infected with Anaplasma, Ehrlichia, Rickettsia, Babesia or Theileria spp. Finally, the effect of subolesin knockdown by RNA interference (RNAi) on tick infection was analyzed in Dermacentor variabilis males exposed to various pathogens by capillary feeding (CF). ; [Results]: Subolesin expression increased with pathogen infection in the salivary glands but not in the guts of tick vector species infected with A. marginale. When analyzed in whole ticks, subolesin expression varied between tick species and in response to different pathogens. As reported previously, subolesin knockdown in D. variabilis infected with A. marginale and other tick-borne pathogens resulted in lower infection levels, while infection with Francisella tularensis increased in ticks after RNAi. When non-tick-borne pathogens were fed to ticks by CF, subolesin RNAi did not affect or resulted in lower infection levels in ticks. However, subolesin expression was upregulated in D. variabilis exposed to Escherichia coli, suggesting that although this pathogen may induce subolesin expression in ticks, silencing of this molecule reduced bacterial multiplication by a presently unknown mechanism. ; [Conclusions]: Subolesin expression in infected ticks suggested that subolesin may be functionally important for tick innate immunity to pathogens, as has been reported for the akirins. However, subolesin expression and consequently subolesin-mediated innate immunity varied with the pathogen and tick tissue. Subolesin may plays a role in tick innate immunity in the salivary glands by limiting pathogen infection levels, but activates innate immunity only for some pathogen in the guts and other tissues. In addition, these results provided additional support for the role of subolesin in other molecular pathways including those required for tissue development and function and for pathogen infection and multiplication in ticks. Consequently, RNAi experiments demonstrated that subolesin knockdown in ticks may affect pathogen infection directly by reducing tick innate immunity that results in higher infection levels and indirectly by affecting tissue structure and function and the expression of genes that interfere with pathogen infection and multiplication. The impact of the direct or indirect effects of subolesin knockdown on pathogen infection may depend on several factors including specific tick-pathogen molecular interactions, pathogen life cycle in the tick and unknown mechanisms affected by subolesin function in the control of global gene expression in ticks. ; This research was supported by the Ministerio de Ciencia e Innovación, Spain (project BFU2008-01244/BMC), the INIA, Spain (project FAU2008-00014- 00-00), the Ministry of Health, Italy (project IZS SI 10-06), the CSIC intramural projects 200830I249 and PA1002025 to JF, the Oklahoma Agricultural Experiment Station (project 1669), the Walter R. Sitlington Endowed Chair for Food Animal Research (K. M. Kocan, Oklahoma State University) and facilitated by ICTTD-3, financed by the International Cooperation Program of the European Union, coordination action project No. 510561. M. Villar was funded by the JAE-DOC program (CSIC-FSE), Spain. ; Peer reviewed

Dogs are the main reservoir of Leishmania infantum and in some countries have been regularly culled as part of government policy to control visceral leishmaniasis. At the 13th Symposium of the Companion Vector-Borne Diseases World Forum in Windsor, UK, March 19-22, 2018, we consolidated a consensus statement regarding the usefulness of dog culling as a means of controlling visceral leishmaniasis. The statement highlighted the futility of culling infected dogs, whether healthy or sick, as a measure to control the domestic reservoir of L. infantum and reduce the risk for visceral leishmaniasis. ; publishersversion ; published