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Ruiz H, de Arcaute MR, Benito AÁ, Villanueva-Saz S, Jiménez JC, Lacasta D. Long-lasting infection with Anaplasma ovis in sheep. Vet Res Commun 2024; 48:521-525. [PMID: 37528260 PMCID: PMC10810980 DOI: 10.1007/s11259-023-10186-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Accepted: 07/22/2023] [Indexed: 08/03/2023]
Abstract
Ovine anaplasmosis is an emerging vector-borne disease in Europe caused by Anaplasma ovis. The infection has spread quickly in recent years, causing moderate to severe outbreaks in sheep flocks, leading to relevant economic losses in sheep farming. This wider spread has been associated with global warming and climate change, favouring the maintenance and life cycle of their main vector, the ticks. However, another epidemiological aspect could favour this quick spread. Long persistence infection of Anaplasma ovis has been proposed as a hypothesis in several articles but never scientifically proven. The results of the present study demonstrate that eight adult sheep, both naturally or experimentally infected, maintain Anaplasma ovis load in blood during their whole productive life (4 to 6 years), being permanently infected. In addition, the results suggest that A. ovis bacterial load can be constant or suffer fluctuations, as has been demonstrated in other Anaplasma species. Both aspects can be determinants in the epidemiology and the transmission of the infection.
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Affiliation(s)
- Héctor Ruiz
- Animal Pathology Department, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, C. Miguel Servet 177, Zaragoza, 50013, Spain.
- Veterinary Faculty, University of Zaragoza, Zaragoza, 50013, Spain.
| | - Marta Ruiz de Arcaute
- Animal Pathology Department, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, C. Miguel Servet 177, Zaragoza, 50013, Spain
- Veterinary Faculty, University of Zaragoza, Zaragoza, 50013, Spain
| | | | - Sergio Villanueva-Saz
- Animal Pathology Department, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, C. Miguel Servet 177, Zaragoza, 50013, Spain
- Veterinary Faculty, University of Zaragoza, Zaragoza, 50013, Spain
| | - José Calasanz Jiménez
- Veterinarios Asesores en Clínica y Sanidad Animal S.L, C. Ramón y Cajal 14, Zaragoza, 50003, Spain
| | - Delia Lacasta
- Animal Pathology Department, Instituto Agroalimentario de Aragón-IA2, Universidad de Zaragoza-CITA, C. Miguel Servet 177, Zaragoza, 50013, Spain
- Veterinary Faculty, University of Zaragoza, Zaragoza, 50013, Spain
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2
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Ulucesme MC, Ozubek S, Aktas M. Molecular Prevalence and Genetic Diversity Based on Msp1a Gene of Anaplasma ovis in Goats from Türkiye. Life (Basel) 2023; 13:life13051101. [PMID: 37240746 DOI: 10.3390/life13051101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 03/30/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Anaplasma ovis is a tick-borne obligated intraerythrocytic bacterium that infects domestic sheep, goats, and wild ruminants. Recently, several studies have been carried out using 16S rRNA and msp4 genes to identify the genetic diversity of A. ovis. Instead of these genes, which are known to be highly stable among heterologous strains, Msp1a, which is accepted as a stable molecular marker to classify A. marginale strains, was used in A. ovis genetic diversity studies. The genetic diversity of A. ovis strains according to the Msp1a gene has not been extensively reported. Therefore, the purpose of this study was to examine the genetic diversity of A. ovis in goats specifically using analysis of the Msp1a gene. Blood samples were taken from the vena jugularis to the EDTA tubes from 293 randomly selected goats (apparently healthy) in the Antalya and Mersin provinces of Mediterranean region of Türkiye. The Msp1a gene of A. ovis was amplified in all DNA samples through the use of PCR, using a specific set of primers named AoMsp1aF and AoMsp1aR. Among the amplified products, well-defined bands with different band sizes were subjected to sequence analysis. The obtained sequence data were converted into amino acid sequences using an online bioinformatics program and the tandem regions were examined. The Msp1a gene of A. ovis was amplified in 46.1% (135 out of 293) of the goats. Through tandem analysis, five distinct tandems (Ao8, Ao18, Tr15-16-17) were identified, and it was found that three of these tandems (Tr15-16-17) were previously unknown and were therefore defined as new tandems. The study also involved examination of ticks from goats. It was observed that the goats in the area were infested with several tick species, including Rhipicephalus bursa (888/1091, 81.4%), R. turanicus (96/1091, 8.8%), Dermacentor raskemensis (92/1091, 8.4%), Hyalomma marginatum (9/1091, 0.8%), and R. sanguineus s.l. (6/1091, 0.5%). This study provides important data for understanding the genetic diversity and evolution of A. ovis based on tandem repeats in the Msp1a protein.
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Affiliation(s)
- Mehmet Can Ulucesme
- Department of Parasitology, Faculty of Veterinary Medicine, University of Firat, Elazig 23119, Türkiye
| | - Sezayi Ozubek
- Department of Parasitology, Faculty of Veterinary Medicine, University of Firat, Elazig 23119, Türkiye
| | - Munir Aktas
- Department of Parasitology, Faculty of Veterinary Medicine, University of Firat, Elazig 23119, Türkiye
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Saratsis A, Ligda P, Aal F, Jelicic M, Polgar J, de Vries M, Mastranestasis I, Musella V, Rinaldi L, Jongejan F, Sotiraki S. The Scenario of Ticks and Tick-Borne Pathogens of Sheep on a Mediterranean Island. Microorganisms 2022; 10:microorganisms10081551. [PMID: 36013969 PMCID: PMC9412349 DOI: 10.3390/microorganisms10081551] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 07/20/2022] [Accepted: 07/28/2022] [Indexed: 01/25/2023] Open
Abstract
Ticks and transmitted pathogens constitute a major concern for livestock health/welfare and productivity for the Mediterranean region, often posing an important zoonotic threat. The aim of this study was to investigate the presence, infection intensity, and seasonality of ticks and tick-borne pathogens on the island of Lesvos in Greece, which was selected as a potential hotspot for their circulation. To this end, 101 sheep farms were visited over a tick activity season, and ticks, blood samples, and questionnaire data were collected. Ticks were identified by species, and DNA from both ticks and blood samples was further investigated using the polymerase chain reaction–reverse line blot (PCR–RLB) technique. In 72.3% of the farms, sheep were found to be infected by 9 ixodid species, with Rhipicephalus turanicus being the most common during the spring/early summer period. As regards tick-borne pathogens (TBPs), 84.9% of the animals were found to be infected with at least one pathogen, the most common being genera of Anaplasma and Theileria, alone or in co-infections. To further characterize the Anaplasma species found, selected samples were sequenced, revealing isolates of A. ovis, A. capra, A. marginale, and A. phagocytophilum. Of the 169 female R. turanicus ticks analyzed by PCR–RLB, 89.9% were harboring at least one TBP belonging to the genera Anaplasma, Ehrlichia, Babesia, Theileria, or Rickettsia. Overall, the data presented in this study revealed a high burden of ticks and TBPs in sheep, including zoonotic species, stressing the need for applying effective monitoring and control programs using a more holistic One Health approach.
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Affiliation(s)
- Anastasios Saratsis
- Veterinary Research Institute, Hellenic Agricultural Organisation-Demeter, 57001 Thessaloniki, Greece; (P.L.); (I.M.)
- Correspondence: (A.S.); or (S.S.)
| | - Panagiota Ligda
- Veterinary Research Institute, Hellenic Agricultural Organisation-Demeter, 57001 Thessaloniki, Greece; (P.L.); (I.M.)
| | - Fredie Aal
- Utrecht Centre for Tick-Borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-Borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; (F.A.); (M.J.); (J.P.); (M.d.V.); or (F.J.)
| | - Mandy Jelicic
- Utrecht Centre for Tick-Borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-Borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; (F.A.); (M.J.); (J.P.); (M.d.V.); or (F.J.)
| | - Juliette Polgar
- Utrecht Centre for Tick-Borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-Borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; (F.A.); (M.J.); (J.P.); (M.d.V.); or (F.J.)
| | - Myrthe de Vries
- Utrecht Centre for Tick-Borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-Borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; (F.A.); (M.J.); (J.P.); (M.d.V.); or (F.J.)
| | - Ioannis Mastranestasis
- Veterinary Research Institute, Hellenic Agricultural Organisation-Demeter, 57001 Thessaloniki, Greece; (P.L.); (I.M.)
| | - Vincenzo Musella
- Department of Health Science, University “Magna Græcia” of Catanzaro, Viale Europa, 88100 Catanzaro, Italy;
| | - Laura Rinaldi
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, CREMOPAR Campania Region, Via Della Veterinaria 1, 80137 Naples, Italy;
| | - Frans Jongejan
- Utrecht Centre for Tick-Borne Diseases (UCTD), FAO Reference Centre for Ticks and Tick-Borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands; (F.A.); (M.J.); (J.P.); (M.d.V.); or (F.J.)
- TBD International B.V., Ramstraat 39, 3581 HE Utrecht, The Netherlands
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria 0110, South Africa
| | - Smaragda Sotiraki
- Veterinary Research Institute, Hellenic Agricultural Organisation-Demeter, 57001 Thessaloniki, Greece; (P.L.); (I.M.)
- Correspondence: (A.S.); or (S.S.)
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Said MB, Attia KA, Alsubki RA, Mohamed AA, Kimiko I, Selim A. Molecular epidemiological survey, genetic characterization and phylogenetic analysis of Anaplasma ovis infecting sheep in Northern Egypt. Acta Trop 2022; 229:106370. [PMID: 35157843 DOI: 10.1016/j.actatropica.2022.106370] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 02/07/2023]
Abstract
Anaplasma ovis is the most common etiologic agent of ovine anaplasmosis, mainly transmitted by ticks. The present study aimed to determine the molecular prevalence of A. ovis in sheep from Egypt and assessed the associated risk factors. The study was conducted, between January and December 2020, in four governorates situated in Northern Egypt. Blood samples from 355 asymptomatic sheep were collected and examined by the use of PCR specific to A. ovis. Diversity analysis and phylogenetic study based on partial msp4 gene sequence were performed on revealed A. ovis DNA. Overall, the molecular prevalence rate of A. ovis was 15.5% and the highest rate was observed in Kafr ElSheikh governorate (16.8%). Statistical analysis revealed that A. ovis infection was significantly related to sheep gender and to tick infestation. The risk factors that were found to be associated with A. ovis infection in exposed sheep were: female sex (OR=2.6, 95%CI: 1.13-6.12), and infestation with ticks (OR=2.1, 95%CI: 1.11-3.79). The analysis of A. ovis msp4 sequences revealed two different genotypes classified in the Old World sub-cluster with other Egyptian isolates. Investigation on prevalence, risk factors and genetic variability of A. ovis in sheep reported in this study is important for the implementation of control programs. Further studies are needed to determine the vectors and reservoirs of A. ovis in Egyptian small ruminants and to identify the real economic impact of A. ovis infection on the country.
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Affiliation(s)
- Mourad Ben Said
- Higher Institute of Biotechnology, BiotechPôlet, BP-66, 2020, Sidi Thabet, Ariana Tunis, University of Manouba, Tunisia; Laboratory of Microbiology, National School of Veterinary Medicine of Sidi Thabet, Ariana Tunis, University of Manouba, Tunisia.
| | - Kotb A Attia
- Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Roua A Alsubki
- Department of Clinical Laboratory Science, College of Applied Medical Sciences, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Arif A Mohamed
- Department of Biochemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
| | - Itoh Kimiko
- Institute of Science and Technology, Niigata University, Ikarashi-2, Nishi-ku, Niigata 950-2181, Japan
| | - Abdelfattah Selim
- Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Benha University, Toukh 13736, Egypt.
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First Molecular Evidence for the Presence of Anaplasma phagocytophilum in Naturally Infected Small Ruminants in Tunisia, and Confirmation of Anaplasma ovis Endemicity. Pathogens 2022; 11:pathogens11030315. [PMID: 35335639 PMCID: PMC8950766 DOI: 10.3390/pathogens11030315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 01/27/2023] Open
Abstract
Anaplasma species are obligate intracellular rickettsial vector-borne pathogens that impose economic constraints on animal breeders and threaten human health. Anaplasma ovis and Anaplasma phagocytophilum infect sheep and goats worldwide. A duplex PCR targeting the msp2 and msp4 genes of A. phagocytophilum and A. ovis, respectively, was developed to analyze the field blood samples collected from sheep and goats. A total of 263 apparently healthy small ruminants from 16 randomly selected flocks situated in 3 bioclimatic zones in Tunisia were analyzed for Anaplasma infections. Anaplasma spp. was detected in 78.3% (95% confidence interval (CI): 72.8–83.1) of the analyzed animals. The prevalence of A. ovis in sheep (80.4%) and goats (70.3%) was higher than that of A. phagocytophilum (7.0% in sheep and 1.6% in goats). Using an inexpensive, specific, and rapid duplex PCR assay, we provide, to the best of our knowledge, the first molecular evidence for the presence of A. phagocytophilum in small ruminants in Tunisia. A. phagocytophilum generally presented as a co-infection with A. ovis. This study provides important data to understand the epidemiology of anaplasmosis in small ruminants, and highlights the risk of contracting the infection upon tick exposure.
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Atif FA, Mehnaz S, Qamar MF, Roheen T, Sajid MS, Ehtisham-ul-Haque S, Kashif M, Ben Said M. Epidemiology, Diagnosis, and Control of Canine Infectious Cyclic Thrombocytopenia and Granulocytic Anaplasmosis: Emerging Diseases of Veterinary and Public Health Significance. Vet Sci 2021; 8:vetsci8120312. [PMID: 34941839 PMCID: PMC8705095 DOI: 10.3390/vetsci8120312] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/26/2021] [Accepted: 11/30/2021] [Indexed: 12/17/2022] Open
Abstract
This review highlights the diagnostic methods used, the control strategies adopted, and the global epidemiological status of canine cyclic thrombocytopenia and granulocytic anaplasmosis at the animal–human interface. Canine anaplasmosis is an important worldwide disease, mainly caused by Anaplasma platys and A. phagocytophilum with zoonotic implications. A. platys chiefly infects platelets in canids, while A. phagocytophilum is the most common zoonotic pathogen infecting neutrophils of various vertebrate hosts. Diagnosis is based on the identification of clinical signs, the recognition of intracellular inclusions observed by microscopic observation of stained blood smear, and/or methods detecting antibodies or nucleic acids, although DNA sequencing is usually required to confirm the pathogenic strain. Serological cross-reactivity is the main problem in serodiagnosis. Prevalence varies from area to area depending on tick exposure. Tetracyclines are significant drugs for human and animal anaplasmosis. No universal vaccine is yet available that protects against diverse geographic strains. The control of canine anaplasmosis therefore relies on the detection of vectors/reservoirs, control of tick vectors, and prevention of iatrogenic/mechanical transmission. The control strategies for human anaplasmosis include reducing high-risk tick contact activities (such as gardening and hiking), careful blood transfusion, by passing immunosuppression, recognizing, and control of reservoirs/vectors.
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Affiliation(s)
- Farhan Ahmad Atif
- Medicine Section, Department of Clinical Sciences, College of Veterinary and Animal Sciences, Jhang, Sub-Campus University of Veterinary and Animal Sciences, Lahore 54600, Pakistan; (S.M.); (M.K.)
- Correspondence: or (F.A.A.); or (M.B.S.); Tel.: +92-47-7671270 (F.A.A.); +216-58-964147 (M.B.S.)
| | - Saba Mehnaz
- Medicine Section, Department of Clinical Sciences, College of Veterinary and Animal Sciences, Jhang, Sub-Campus University of Veterinary and Animal Sciences, Lahore 54600, Pakistan; (S.M.); (M.K.)
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Pakistan;
| | - Muhammad Fiaz Qamar
- Department of Pathobiology, College of Veterinary and Animal Sciences, Jhang, Sub-Campus University of Veterinary and Animal Sciences, Lahore 54600, Pakistan; (M.F.Q.); (S.E.-u.-H.)
| | - Taleeha Roheen
- Department of Chemistry (Biochemistry), University of Sargodha, Sargodha 40100, Pakistan;
| | - Muhammad Sohail Sajid
- Department of Parasitology, Faculty of Veterinary Science, University of Agriculture, Faisalabad 38000, Pakistan;
| | - Syed Ehtisham-ul-Haque
- Department of Pathobiology, College of Veterinary and Animal Sciences, Jhang, Sub-Campus University of Veterinary and Animal Sciences, Lahore 54600, Pakistan; (M.F.Q.); (S.E.-u.-H.)
| | - Muhammad Kashif
- Medicine Section, Department of Clinical Sciences, College of Veterinary and Animal Sciences, Jhang, Sub-Campus University of Veterinary and Animal Sciences, Lahore 54600, Pakistan; (S.M.); (M.K.)
| | - Mourad Ben Said
- Higher Institute of Biotechnology of Sidi Thabet, University of Manouba, Manouba 2010, Tunisia
- Laboratory of Microbiology at the National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Manouba 2010, Tunisia
- Correspondence: or (F.A.A.); or (M.B.S.); Tel.: +92-47-7671270 (F.A.A.); +216-58-964147 (M.B.S.)
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Iqbal N, Mukhtar MU, Yang J, Niu Q, Li Z, Zhao S, Zhao Y, Guan G, Liu Z, Yin H. Identification and evaluation of midgut protein RL12 of Dermacentor silvarum interacting with Anaplasma ovis VirD4. Ticks Tick Borne Dis 2021; 12:101677. [PMID: 33549977 DOI: 10.1016/j.ttbdis.2021.101677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 01/16/2021] [Accepted: 01/17/2021] [Indexed: 11/15/2022]
Abstract
Anaplasma ovis, a tick-borne intra-erythrocytic Gram-negative bacterium, is a causative agent of ovine anaplasmosis. It is known that Dermacentor ticks act as biological vectors for A. ovis. VirD4 is the machine component of Type IV Secretion System of A. ovis. To better understand the pathogen-vector interaction, VirD4 was used as a bait protein for screening midgut proteins of Dermacentor silvarum via yeast two-hybrid mating assay. As a result, a ribosomal protein RL12 was identified from the midgut cDNA library of D. silvarum. For further validation, using in vitro Glutathione S-transferase (GST) pull-down assay, interaction between the proteins, GST-RL12 and HIS-VirD4, was observed in Western blot analysis. The study is first of its kind reporting a D. silvarum midgut protein interaction with VirD4 from A. ovis. Functional annotations showed some important cellular processes are attributed to the protein, particularly in the stringent response and biogenesis. The results of the study suggest the involvement of the VirD4-RL12 interaction in the regulation of signaling pathways, which is a tool for understanding the pathogen-vector interaction.
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Affiliation(s)
- Naveed Iqbal
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Muhammad Uzair Mukhtar
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Jifei Yang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Qingli Niu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Zhi Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Shuaiyang Zhao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Yaru Zhao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Guiquan Guan
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Zhijie Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China.
| | - Hong Yin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, PR China; Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, PR China.
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Han R, Yang J, Liu Z, Gao S, Niu Q, Hassan MA, Luo J, Yin H. Characterization of Anaplasma ovis strains using the major surface protein 1a repeat sequences. Parasit Vectors 2017; 10:447. [PMID: 28962625 PMCID: PMC5622584 DOI: 10.1186/s13071-017-2363-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 09/05/2017] [Indexed: 12/03/2022] Open
Affiliation(s)
- Rong Han
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China.,Qinghai Provincial Center for Animal Disease Control and Prevention, Xining, 810003, Qinghai, People's Republic of China
| | - Jifei Yang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Zhijie Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Shaodian Gao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Qingli Niu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Muhammad Adeel Hassan
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Jianxun Luo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China
| | - Hong Yin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Xujiaping 1, Lanzhou, Gansu, 730046, People's Republic of China. .,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009, People's Republic of China.
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Wang Z, Yang J, Niu Q, Brayton KA, Luo J, Liu G, Yin H, Liu Z. Identification of Anaplasma ovis appendage-associated protein (AAAP) for development of an indirect ELISA and its application. Parasit Vectors 2017; 10:359. [PMID: 28754151 PMCID: PMC5534110 DOI: 10.1186/s13071-017-2297-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 07/17/2017] [Indexed: 12/20/2022] Open
Abstract
Background Ovine anaplasmosis is a tick-borne disease that is caused by Anaplasma ovis in sheep and goats. The pathogen is widely distributed in tropical and subtropical regions of the world. At present, diagnosis of the disease mainly depends on microscopy or nucleic acid based molecular tests, although a few serological tests have been applied for the detection of A. ovis infection. Results Here we describe the identification of an A. ovis protein that is homologous to the A. marginale appendage-associated protein (AAAP). We expressed a recombinant fragment of this protein for the development of an indirect enzyme-linked immunosorbent assay (ELISA) for the detection of A. ovis. Anaplasma ovis-positive serum showed specific reactivity to recombinantly expressed AAAP (rAAAP), which was further confirmed by the rAAAP ELISA, which also demonstrated no cross-reactivity with sera from animals infected with A. bovis or other related pathogens in sheep and goats. Testing antibody kinetics of five experimentally infected sheep for 1 year demonstrated that the rAAAP ELISA is suitable for the detection of early and persistent infection of A. ovis infections. Investigation of 3138 field-collected serum samples from 54 regions in 23 provinces in China demonstrated that the seroprevalence varied from 9.4% to 65.3%, which is in agreement with previous reports of A. ovis infection. Conclusions An A. ovis derived antigenic protein, AAAP, was identified and the antigenicity of the recombinant AAAP was confirmed. Using rAAAP an indirect ELISA assay was established, and the assay has been proven to be an alternative serological diagnostic tool for investigating the prevalence of ovine anaplasmosis of sheep and goats.
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Affiliation(s)
- Zhenguo Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China
| | - Jifei Yang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China
| | - Qingli Niu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China
| | - Kelly A Brayton
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164, USA
| | - Jianxun Luo
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China
| | - Guangyuan Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China
| | - Hong Yin
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases, Yangzhou, China
| | - Zhijie Liu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, People's Republic of China.
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10
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Silaghi C, Santos AS, Gomes J, Christova I, Matei IA, Walder G, Domingos A, Bell-Sakyi L, Sprong H, von Loewenich FD, Oteo JA, de la Fuente J, Dumler JS. Guidelines for the Direct Detection of Anaplasma spp. in Diagnosis and Epidemiological Studies. Vector Borne Zoonotic Dis 2017; 17:12-22. [PMID: 28055579 DOI: 10.1089/vbz.2016.1960] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The genus Anaplasma (Rickettsiales: Anaplasmataceae) comprises obligate intracellular Gram-negative bacteria that are mainly transmitted by ticks, and currently includes six species: Anaplasma bovis, Anaplasma centrale, Anaplasma marginale, Anaplasma phagocytophilum, Anaplasma platys, and Anaplasma ovis. These have long been known as etiological agents of veterinary diseases that affect domestic and wild animals worldwide. A zoonotic role has been recognized for A. phagocytophilum, but other species can also be pathogenic for humans. Anaplasma infections are usually challenging to diagnose, clinically presenting with nonspecific symptoms that vary greatly depending on the agent involved, the affected host, and other factors such as immune status and coinfections. The substantial economic impact associated with livestock infection and the growing number of human cases along with the risk of transfusion-transmitted infections, determines the need for accurate laboratory tests. Because hosts are usually seronegative in the initial phase of infection and serological cross-reactions with several Anaplasma species are observed after seroconversion, direct tests are the best approach for both case definition and epidemiological studies. Blood samples are routinely used for Anaplasma spp. screening, but in persistently infected animals with intermittent or low-level bacteremia, other tissues might be useful. These guidelines have been developed as a direct outcome of the COST action TD1303 EURNEGVEC ("European Network of Neglected Vectors and Vector-Borne Diseases"). They review the direct laboratory tests (microscopy, nucleic acid-based detection and in vitro isolation) currently used for Anaplasma detection in ticks and vertebrates and their application.
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Affiliation(s)
- Cornelia Silaghi
- 1 National Center for Vector Entomology, Vetsuisse Faculty, University of Zurich , Zurich, Switzerland
| | - Ana Sofia Santos
- 2 Center for Vector and Infectious Diseases Research, National Institute of Health Doutor Ricardo Jorge , Águas de Moura, Portugal
| | - Jacinto Gomes
- 3 Animal Health and Production Unit, National Institute for Agrarian and Veterinary Research , Oeiras, Portugal
| | - Iva Christova
- 4 Department of Microbiology, National Center of Infectious and Parasitic Diseases , Sofia, Bulgaria
| | - Ioana Adriana Matei
- 5 Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca , Cluj-Napoca, Romania
| | - Gernot Walder
- 6 Department of Hygiene, Medical Microbiology and Social Medicine, Innsbruck Medical University , Innsbruck, Austria
| | - Ana Domingos
- 7 Global Health and Tropical Medicine, Instituto de Higiene e Medicina Tropical, Universidade Nova de Lisboa , Lisboa, Portugal
| | - Lesley Bell-Sakyi
- 8 The Pirbright Institute , Ash Road, Pirbright, Woking, Surrey, United Kingdom
| | - Hein Sprong
- 9 Center for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM) , Bilthoven, the Netherlands
| | | | - José A Oteo
- 11 Infectious Diseases Department, Center of Rickettsioses and Arthropod-Borne Diseases , Hospital San Pedro- CIBIR, Logroño, Spain
| | - José de la Fuente
- 12 SaBio. Instituto de Investigación de Recursos Cinegéticos, IREC-CSIC-UCLM-JCCM, Ciudad Real, Spain .,13 Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University , Stillwater, Oklahoma
| | - J Stephen Dumler
- 14 Departments of Pathology and Microbiology and Immunology, University of Maryland , School of Medicine, Baltimore, Maryland.,15 Department of Pathology, Uniformed Services University for the Health Sciences "America's Medical School," Bethesda, Maryland
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11
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Eisawi NM, Hassan DA, Hussien MO, Musa AB, El Hussein ARM. Seroprevalence of spotted fever group (SFG) rickettsiae infection in domestic ruminants in Khartoum State, Sudan. Vet Med Sci 2017; 3:91-98. [PMID: 28713577 PMCID: PMC5488242 DOI: 10.1002/vms3.59] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 11/11/2022] Open
Abstract
Spotted fever group (SFG) rickettsiosis is caused by obligatory intracellular Gram-negative bacteria that belong to the genus Rickettsia. Ticks belonging to the family Ixodidae can act as vectors, reservoirs or amplifiers of SFG rickettsiae. This study was conducted to estimate the seroprevalence of SFG rickettsioses in cattle, sheep and goats from Khartoum State, Sudan. Blood samples were collected from a total of 600 animals (sheep, goats and cattle) from 32 different farms distributed in three locations in Khartoum State during the period January to December 2012. Sera were tested for antibodies against SFG rickettsiae using IFAT. The prevalence of seropositivity was 59.3% in sheep, 60.1% in goats and 64.4% in cattle. Season was significantly (P < 0.05) associated with seroprevalence of SFG rickettsiae in cattle during winter. The SFG rickettsiae antibodies prevalence was significantly higher in female compared with male in sheep, but there were no significant differences between male and female in either cattle or goats. The prevalence was significantly higher in adult animals compared with young in both sheep and goats. With regard to management system, there was a significant difference in the prevalence in cattle raised in closed system compared with those raised in semi-intensive system. In contrast, there was significant difference in the seroprevalence of SFG in sheep where the prevalence was higher in the sheep raised in semi-intensive system compared with those raised in close system. There was no significant difference in the seroprevalence in goats with regard to management systems. The unexpected high prevalence of SFG rickettsia antibodies in domestic ruminants sera suggest that the veterinary and public health impact of these agents in Sudan need further evaluation especially in humans.
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Affiliation(s)
- Nagwa M Eisawi
- Central LaboratoryMinistry of Higher Education and Scientific ResearchP.O. Box 7099KhartoumSudan
| | - Dina A Hassan
- Central LaboratoryMinistry of Higher Education and Scientific ResearchP.O. Box 7099KhartoumSudan
| | - Mohammed O Hussien
- Central LaboratoryMinistry of Higher Education and Scientific ResearchP.O. Box 7099KhartoumSudan
| | - Azza B Musa
- Central LaboratoryMinistry of Higher Education and Scientific ResearchP.O. Box 7099KhartoumSudan
| | - Abdel Rahim M El Hussein
- Central Veterinary Research Laboratory (CVRL)Animal Resources Research Corporation (ARRC)P.O. Box 8067El Amarat, KhartoumSudan
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12
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Battilani M, De Arcangeli S, Balboni A, Dondi F. Genetic diversity and molecular epidemiology of Anaplasma. INFECTION GENETICS AND EVOLUTION 2017; 49:195-211. [PMID: 28122249 DOI: 10.1016/j.meegid.2017.01.021] [Citation(s) in RCA: 123] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 01/18/2017] [Accepted: 01/19/2017] [Indexed: 11/25/2022]
Abstract
Anaplasma are obligate intracellular bacteria of cells of haematopoietic origin and are aetiological agents of tick-borne diseases of both veterinary and medical interest common in both tropical and temperate regions. The recent disclosure of their zoonotic potential has greatly increased interest in the study of these bacteria, leading to the recent reorganisation of Rickettsia taxonomy and to the possible discovery of new species belonging to the genus Anaplasma. This review is particularly focused on the common and unique characteristics of Anaplasma marginale and Anaplasma phagocytophilum, with an emphasis on genetic diversity and evolution, and the main distinguishing features of the diseases caused by the different Anaplasma spp. are described as well.
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Affiliation(s)
- Mara Battilani
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Via Tolara di Sopra, 50, 40064 Ozzano Emilia, Bo, Italy.
| | - Stefano De Arcangeli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Via Tolara di Sopra, 50, 40064 Ozzano Emilia, Bo, Italy
| | - Andrea Balboni
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Via Tolara di Sopra, 50, 40064 Ozzano Emilia, Bo, Italy
| | - Francesco Dondi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum - University of Bologna, Via Tolara di Sopra, 50, 40064 Ozzano Emilia, Bo, Italy
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13
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Abstract
Antigenic variation is a strategy used by a broad diversity of microbial pathogens to persist within the mammalian host. Whereas viruses make use of a minimal proofreading capacity combined with large amounts of progeny to use random mutation for variant generation, antigenically variant bacteria have evolved mechanisms which use a stable genome, which aids in protecting the fitness of the progeny. Here, three well-characterized and highly antigenically variant bacterial pathogens are discussed: Anaplasma, Borrelia, and Neisseria. These three pathogens display a variety of mechanisms used to create the structural and antigenic variation needed for immune escape and long-term persistence. Intrahost antigenic variation is the focus; however, the role of these immune escape mechanisms at the population level is also presented.
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14
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15
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López V, Alberdi P, Mera IGFD, Barasona JA, Vicente J, Garrido JM, Torina A, Caracappa S, Lelli RC, Gortázar C, de la Fuente J. Evidence of co-infection with Mycobacterium bovis and tick-borne pathogens in a naturally infected sheep flock. Ticks Tick Borne Dis 2016; 7:384-9. [DOI: 10.1016/j.ttbdis.2015.12.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 11/11/2015] [Accepted: 12/14/2015] [Indexed: 12/31/2022]
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16
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Brown WC, Barbet AF. Persistent Infections and Immunity in Ruminants to Arthropod-Borne Bacteria in the Family Anaplasmataceae. Annu Rev Anim Biosci 2015; 4:177-97. [PMID: 26734888 DOI: 10.1146/annurev-animal-022513-114206] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tick-transmitted gram-negative bacteria in the family Anaplasmataceae in the order Rickettsiales cause persistent infection and morbidity and mortality in ruminants. Whereas Anaplasma marginale infection is restricted to ruminants, Anaplasma phagocytophilum is promiscuous and, in addition to causing disease in sheep and cattle, notably causes disease in humans, horses, and dogs. Although the two pathogens invade and replicate in distinct blood cells (erythrocytes and neutrophils, respectively), they have evolved similar mechanisms of antigenic variation in immunodominant major surface protein 2 (MSP2) and MSP2(P44) that result in immune evasion and persistent infection. Furthermore, these bacteria have evolved distinct strategies to cause immune dysfunction, characterized as an antigen-specific CD4 T-cell exhaustion for A. marginale and a generalized immune suppression for A. phagocytophilum, that also facilitate persistence. This indicates highly adapted strategies of Anaplasma spp. to both suppress protective immune responses and evade those that do develop. However, conserved subdominant antigens are potential targets for immunization.
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Affiliation(s)
- Wendy C Brown
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164;
| | - Anthony F Barbet
- Department of Infectious Diseases and Pathology, University of Florida, Gainesville, Florida 32611;
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17
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Belkahia H, Ben Said M, El Hamdi S, Yahiaoui M, Gharbi M, Daaloul-Jedidi M, Mhadhbi M, Jedidi M, Darghouth MA, Klabi I, Zribi L, Messadi L. First molecular identification and genetic characterization of Anaplasma ovis in sheep from Tunisia. Small Rumin Res 2014. [DOI: 10.1016/j.smallrumres.2014.07.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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18
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Nuñez PA, Moretta R, Ruybal P, Wilkowsky S, Farber MD. Immunogenicity of Hypothetical Highly Conserved Proteins as Novel Antigens in Anaplasma marginale. Curr Microbiol 2013; 68:269-77. [DOI: 10.1007/s00284-013-0475-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 09/04/2013] [Indexed: 12/19/2022]
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19
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Tate CM, Howerth EW, Mead DG, Dugan VG, Luttrell MP, Sahora AI, Munderloh UG, Davidson WR, Yabsley MJ. Anaplasma odocoilei sp. nov. (family Anaplasmataceae) from white-tailed deer (Odocoileus virginianus). Ticks Tick Borne Dis 2012; 4:110-9. [PMID: 23276749 DOI: 10.1016/j.ttbdis.2012.09.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 09/11/2012] [Accepted: 09/24/2012] [Indexed: 11/16/2022]
Abstract
Recently, an undescribed Anaplasma sp. (also called Ehrlichia-like sp. or WTD agent) was isolated in ISE6 tick cells from captive white-tailed deer. The goal of the current study was to characterize this organism using a combination of experimental infection, morphologic, serologic, and molecular studies. Each of 6 experimentally inoculated white-tailed deer fawns (Odocoileus virginianus) became chronically infected (100+ days) with the Anaplasma sp. by inoculation of either infected whole blood or culture. None of the deer showed evidence of clinical disease, but 3 of the 6 deer evaluated had multiple episodes of transient thrombocytopenia. Light microscopy of Giemsa-stained, thin blood smears revealed tiny, dark, spherical structures in platelets of acutely infected deer. Anaplasma sp. was detected in platelets of inoculated deer by polymerase chain reaction, transmission electron microscopy, immunohistochemistry, and in situ hybridization. Five of 6 deer developed antibodies reactive to Anaplasma sp. antigen, as detected by indirect fluorescent antibody testing. Phylogenetic analyses of 16S rRNA, groESL, and gltA sequences confirmed the Anaplasma sp. is related to A. platys. Two attempts to transmit the Anaplasma sp. between deer by feeding Amblyomma americanum, a suspected tick vector, were unsuccessful. Based on its biologic, antigenic, and genetic characteristics, this organism is considered a novel species of Anaplasma, and the name Anaplasma odocoilei sp. nov. is proposed with UMUM76(T) (=CSUR-A1) as the type strain.
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Affiliation(s)
- Cynthia M Tate
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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20
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Molecular survey and genetic identification of Anaplasma species in goats from central and southern China. Appl Environ Microbiol 2011; 78:464-70. [PMID: 22057867 DOI: 10.1128/aem.06848-11] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Anaplasma species are obligate intracellular rickettsial pathogens that impact the health of humans and animals. Few studies have been carried out on Anaplasma infections in central and southern China. This study was conducted to determine the coinfection rates of Anaplasma ovis, A. bovis, and A. phagocytophilum from 262 field blood samples of goats in these regions. The average prevalences of single infection of A. ovis, A. bovis, and A. phagocytophilum were 15.3, 16.0, and 6.1%, respectively. Coinfection of A. ovis and A. bovis was dominant, with an infection rate of 27.1%. Coinfection of A. ovis and A. phagocytophilum was 1.9% and that of A. bovis and A. phagocytophilum was 4.2%. Three-pathogen coinfection was found in three of four investigated provinces with a prevalence between 0 and 5.3%. The accuracy of the PCR results was corroborated by sequencing. Analysis of the 16S rRNA gene sequences of A. bovis and A. phagocytophilum confirmed the presence of these pathogens at the investigated sites and indicated the possible genetic diversity of A. phagocytophilum. Field blood inoculation of experimental animals led to successful identification and observation of the morphological shapes of A. bovis in the infected monocytes of sheep. Phylogenetic study with msp4 sequences of A. ovis indicated that the A. ovis genotypes from sheep in the north differed from the genotypes of goats in the investigated sites.
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21
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Treatment and Control of Chlamydial and Rickettsial Infections in Sheep and Goats. Vet Clin North Am Food Anim Pract 2011; 27:213-233. [DOI: 10.1016/j.cvfa.2010.10.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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22
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Chochlakis D, Ioannou I, Tselentis Y, Psaroulaki A. Human anaplasmosis and Anaplasma ovis variant. Emerg Infect Dis 2010; 16:1031-2. [PMID: 20507768 PMCID: PMC3086243 DOI: 10.3201/eid1606.090175] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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23
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Molecular epidemiology of bovine anaplasmosis with a particular focus in Mexico. INFECTION GENETICS AND EVOLUTION 2009; 9:1092-101. [PMID: 19786123 DOI: 10.1016/j.meegid.2009.09.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Revised: 09/15/2009] [Accepted: 09/21/2009] [Indexed: 11/21/2022]
Abstract
Bovine anaplasmosis, caused by the rickettsia Anaplasma marginale, has a worldwide distribution and is the cause of great economic losses in developing countries where it is highly endemic. Transmission is carried mainly by ixodid ticks: Dermacentor spp. and Rhipicephalus (Boophilus) spp. Mechanical transmission is important in disseminating the disease within and across herds. The relationship between the rickettsia, the host and the vector is complex. Several surface proteins (Msps) have been described with functions that span from adhesins towards the erythrocyte and tick cells to evasion of the immune system of the host through the generation of antigenic variants. Biologic transmission of A. marginale through Dermacentor ticks has been well studied but many questions are unresolved as to how this organism spreads within and across herds and little is known about the role Rhipicephalus (Boophilus) ticks play in transmission in the Americas. Mechanical transmission in the absence of ticks and lack of transmission through ticks are questions that need to be addressed. Phylogenetic studies of the rickettsia show wide antigenic and genetic mosaics which affects the design of new vaccines. In the present work we will discuss the molecular elements in the relationship between the rickettsia, the tick and the mammalian host associated to the distribution and persistence of the pathogen in nature.
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24
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de la Fuente J, Kocan KM, Blouin EF, Zivkovic Z, Naranjo V, Almazán C, Esteves E, Jongejan F, Daffre S, Mangold AJ. Functional genomics and evolution of tick-Anaplasma interactions and vaccine development. Vet Parasitol 2009; 167:175-86. [PMID: 19819630 DOI: 10.1016/j.vetpar.2009.09.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several tick-transmitted pathogens that impact veterinary and human health. Tick-borne pathogens cycle between tick vectors and vertebrate hosts and their interaction is mediated by molecular mechanisms at the tick-pathogen interface. These mechanisms have evolved characteristics that involve traits from both the tick vector and the pathogen to insure their mutual survival. Herein, we review the information obtained from functional genomics and genetic studies to characterize the tick-Anaplasma interface and evolution of A. marginale and A. phagocytophilum. Anaplasma and tick genes and proteins involved in tick-pathogen interactions were characterized. The results of these studies demonstrated that common and Anaplasma species-specific molecular mechanism occur by which pathogen and tick cell gene expression mediates or limits Anaplasma developmental cycle and trafficking through ticks. These results have advanced our understanding of the biology of tick-Anaplasma interactions and have opened new avenues for the development of improved methods for the control of tick infestations and the transmission of tick-borne pathogens.
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Affiliation(s)
- José de la Fuente
- Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK 74078, USA.
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25
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Psaroulaki A, Chochlakis D, Sandalakis V, Vranakis I, Ioannou I, Tselentis Y. Phylogentic analysis of Anaplasma ovis strains isolated from sheep and goats using groEL and mps4 genes. Vet Microbiol 2009; 138:394-400. [DOI: 10.1016/j.vetmic.2009.04.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 04/03/2009] [Accepted: 04/14/2009] [Indexed: 10/20/2022]
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26
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Hornok S, Elek V, de la Fuente J, Naranjo V, Farkas R, Majoros G, Földvári G. First serological and molecular evidence on the endemicity of Anaplasma ovis and A. marginale in Hungary. Vet Microbiol 2007; 122:316-22. [PMID: 17336001 DOI: 10.1016/j.vetmic.2007.01.024] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 01/26/2007] [Accepted: 01/29/2007] [Indexed: 10/23/2022]
Abstract
Recurring and spontaneously curing spring haemoglobinuria was recently reported in a small sheep flock in a selenium deficient area of northern Hungary. In blood smears of two animals showing clinical signs, Anaplasma-like inclusion bodies were seen in erythrocytes. To extend the scope of the study, 156 sheep from 5 flocks and 26 cattle from 9 farms in the region were examined serologically with a competitive ELISA to detect antibodies to Anaplasma marginale, A. centrale and A. ovis. The seropositivity in sheep was 99.4%, and in cattle 80.8%. A. ovis and A. marginale were identified by PCR and sequence analysis of the major surface protein (msp) 4 gene in sheep and cattle, respectively. Haemoglobinuria, an unusual clinical sign for anaplasmosis might have been a consequence of transient intravascular haemolysis facilitated by selenium deficiency in recently infected sheep, as indicated by the reduction of mean corpuscular haemoglobin concentration (MCHC). Membrane damage was also demonstrated for parenchymal cells, since their enzymes showed pronounced elevation in the plasma. Ticks collected from animals in the affected as well as in neighbouring flocks revealed the presence of Dermacentor marginatus, Ixodes ricinus and D. reticulatus, with the dominance of the first. The present data extend the northern latitude in the geographical occurrence of ovine anaplasmosis in Europe and reveal the endemicity of A. ovis and A. marginale in Hungary.
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Affiliation(s)
- Sándor Hornok
- Department of Parasitology and Zoology, Faculty of Veterinary Science, Szent István University, István u 2, Budapest, Hungary.
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Palmer GH, Futse JE, Knowles DP, Brayton KA. Insights into mechanisms of bacterial antigenic variation derived from the complete genome sequence of Anaplasma marginale. Ann N Y Acad Sci 2007; 1078:15-25. [PMID: 17114676 DOI: 10.1196/annals.1374.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Persistence of Anaplasma spp. in the animal reservoir host is required for efficient tick-borne transmission of these pathogens to animals and humans. Using A. marginale infection of its natural reservoir host as a model, persistent infection has been shown to reflect sequential cycles in which antigenic variants emerge, replicate, and are controlled by the immune system. Variation in the immunodominant outer-membrane protein MSP2 is generated by a process of gene conversion, in which unique hypervariable region sequences (HVRs) located in pseudogenes are recombined into a single operon-linked msp2 expression site. Although organisms expressing whole HVRs derived from pseudogenes emerge early in infection, long-term persistent infection is dependent on the generation of complex mosaics in which segments from different HVRs recombine into the expression site. The resulting combinatorial diversity generates the number of variants both predicted and shown to emerge during persistence.
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Affiliation(s)
- Guy H Palmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
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de la Fuente J, Lew A, Lutz H, Meli ML, Hofmann-Lehmann R, Shkap V, Molad T, Mangold AJ, Almazán C, Naranjo V, Gortázar C, Torina A, Caracappa S, García-Pérez AL, Barral M, Oporto B, Ceci L, Carelli G, Blouin EF, Kocan KM. Genetic diversity of anaplasma species major surface proteins and implications for anaplasmosis serodiagnosis and vaccine development. Anim Health Res Rev 2005; 6:75-89. [PMID: 16164010 DOI: 10.1079/ahr2005104] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The genus Anaplasma (Rickettsiales: Anaplasmataceae) includes several pathogens of veterinary and human medical importance. An understanding of the diversity of Anaplasma major surface proteins (MSPs), including those MSPs that modulate infection, development of persistent infections, and transmission of pathogens by ticks, is derived in part, by characterization and phylogenetic analyses of geographic strains. Information concerning the genetic diversity of Anaplasma spp. MSPs will likely influence the development of serodiagnostic assays and vaccine strategies for the control of anaplasmosis.
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Affiliation(s)
- José de la Fuente
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078-2007, USA.
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Abbott JR, Palmer GH, Kegerreis KA, Hetrick PF, Howard CJ, Hope JC, Brown WC. Rapid and long-term disappearance of CD4+ T lymphocyte responses specific for Anaplasma marginale major surface protein-2 (MSP2) in MSP2 vaccinates following challenge with live A. marginale. THE JOURNAL OF IMMUNOLOGY 2005; 174:6702-15. [PMID: 15905510 DOI: 10.4049/jimmunol.174.11.6702] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In humans and ruminants infected with Anaplasma, the major surface protein 2 (MSP2) is immunodominant. Numerous CD4(+) T cell epitopes in the hypervariable and conserved regions of MSP2 contribute to this immunodominance. Antigenic variation in MSP2 occurs throughout acute and persistent infection, and sequentially emerging variants are thought to be controlled by variant-specific Ab. This study tested the hypothesis that challenge of cattle with Anaplasma marginale expressing MSP2 variants to which the animals had been immunized, would stimulate variant epitope-specific recall CD4(+) T cell and IgG responses and organism clearance. MSP2-specific T lymphocyte responses, determined by IFN-gamma ELISPOT and proliferation assays, were strong before and for 3 wk postchallenge. Surprisingly, these responses became undetectable by the peak of rickettsemia, composed predominantly of organisms expressing the same MSP2 variants used for immunization. Immune responsiveness remained insignificant during subsequent persistent A. marginale infection up to 1 year. The suppressed response was specific for A. marginale, as responses to Clostridium vaccine Ag were consistently observed. CD4(+)CD25(+) T cells and cytokines IL-10 and TGF-beta1 did not increase after challenge. Furthermore, a suppressive effect of nonresponding cells was not observed. Lymphocyte proliferation and viability were lost in vitro in the presence of physiologically relevant numbers of A. marginale organisms. These results suggest that loss of memory T cell responses following A. marginale infection is due to a mechanism other than induction of T regulatory cells, such as peripheral deletion of MSP2-specific T cells.
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Affiliation(s)
- Jeffrey R Abbott
- Program in Vector-Borne Disease, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, 99164, USA
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30
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Abbott JR, Palmer GH, Howard CJ, Hope JC, Brown WC. Anaplasma marginale major surface protein 2 CD4+-T-cell epitopes are evenly distributed in conserved and hypervariable regions (HVR), whereas linear B-cell epitopes are predominantly located in the HVR. Infect Immun 2004; 72:7360-6. [PMID: 15557669 PMCID: PMC529150 DOI: 10.1128/iai.72.12.7360-7366.2004] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Organisms in the genus Anaplasma express an immunodominant major surface protein 2 (MSP2), composed of a central hypervariable region (HVR) flanked by highly conserved regions. Throughout Anaplasma marginale infection, recombination results in the sequential appearance of novel MSP2 variants and subsequent control of rickettsemia by the immune response, leading to persistent infection. To determine whether immune evasion and selection for variant organisms is associated with a predominant response against HVR epitopes, T-cell and linear B-cell epitopes were localized by measuring peripheral blood gamma interferon-secreting cells, proliferation, and antibody binding to 27 overlapping peptides spanning MSP2 in 16 cattle. Similar numbers of MSP2-specific CD4(+) T-cell epitopes eliciting responses of similar magnitude were found in conserved and hypervariable regions. T-cell epitope clusters recognized by the majority of animals were identified in the HVR (amino acids [aa] 171 to 229) and conserved regions (aa 101 to 170 and 272 to 361). In contrast, linear B-cell epitopes were concentrated in the HVR, residing within hydrophilic sequences. The pattern of recognition of epitope clusters by T cells and of HVR epitopes by B cells is consistent with the influence of protein structure on epitope recognition.
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Affiliation(s)
- Jeffrey R Abbott
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
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31
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Löhr CV, Brayton KA, Barbet AF, Palmer GH. Characterization of the Anaplasma marginale msp2 locus and its synteny with the omp1/p30 loci of Ehrlichia chaffeensis and E. canis. Gene 2004; 325:115-21. [PMID: 14697516 DOI: 10.1016/j.gene.2003.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Major surface protein 2 (MSP2) is an immunodominant and antigenically variant protein in the outer membrane of the rickettsia Anaplasma marginale. MSP2 variation is generated by recombination into a single operon-linked genomic expression site. The complete 5.6-kb msp2 locus was identified by sequencing a 90-kb region of the St. Maries strain of A. marginale. The locus encoded, in a 5' to 3' direction, a transcriptional regulator followed by five outer membrane proteins, OMP1, OpAG3, OpAG2, OpAG1, and MSP2. The sequences of this entire locus were analyzed using six genetically and phenotypically distinct strains of A. marginale. The overall locus structure was highly conserved with 100% identity among strains in the transcriptional regulator. Synonymous and nonsynonymous exchanges were infrequent in omp1 and rare in opag1 and opag2 among the six strains without strong bias for either type of exchange (neutral mutations). In contrast, mutations in opag3 seem to underlie purifying (negative) selection reflecting pressure to retain protein structure, in marked contrast to the highly antigenically variant MSP2. Interestingly, the 5' structure of this A. marginale msp2 locus is conserved in the omp1 gene locus of Ehrlichia chaffeensis and p30 gene locus of E. canis despite marked divergence between genera in the structure of the 3' region of the loci. This supports the hypothesis that the expression sites of these important immunogenic proteins are derived from a common precursor with later divergent evolution along genus lines.
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Affiliation(s)
- Christiane V Löhr
- Program in Vector-Borne Diseases, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA
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32
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Lew AE, Gale KR, Minchin CM, Shkap V, de Waal DT. Phylogenetic analysis of the erythrocytic Anaplasma species based on 16S rDNA and GroEL (HSP60) sequences of A. marginale, A. centrale, and A. ovis and the specific detection of A. centrale vaccine strain. Vet Microbiol 2003; 92:145-60. [PMID: 12488078 DOI: 10.1016/s0378-1135(02)00352-8] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Phenotypic criteria for the identification of erythrocytic ruminant Anaplasma species has relied on subjective identification methods such as host pathogenicity (virulence for cattle or sheep) and/or the location of Anaplasma inclusion bodies within the host's red cells. Sequence comparisons of new and available GenBank Accessions were investigated to elucidate the relationships among these closely related Anaplasma species. Twenty-one 16S rDNA and GroEL (HSP60) sequences from 13 Anaplasma marginale (South Africa, Namibia, Zimbabwe, Israel, USA, Australia and Uruguay), three A. centrale (South Africa and Japan), two A. ovis (USA and South Africa), and two unknown Anaplasma species isolated from wild ruminants (South Africa), were compared. 16S rDNA maximum-likelihood and distance trees separated all A. marginale (and the two wild ruminant isolates) from the two South African A. centrale (including original vaccine strain, Theiler, 1911). The Japanese A. centrale (Aomori) demonstrated the lowest sequence identity to the remaining erythrocytic Anaplasma species. A. ovis inter-species relationships could not be resolved through the 16S rDNA analyses, whereas strong bootstrap branch support is demonstrated in the GroEL distance tree using A. ovis OVI strain. All erythrocytic Anaplasma species and isolates were confirmed to belong to the same cluster showing strong branch support to Anaplasma (Ehrlichia) phagocytophilum with Ehrlichia (Cowdria) ruminantium and Rickettsia rickettsii serving as appropriate out-groups. Based on groEL sequences, a specific PCR method was developed which amplified A. centrale vaccine (Theiler, 1911) specifically. This study confirms the suitability of 16S rDNA sequences to define genera and demonstrates the usefulness of GroEL sequences for defining species of erythrocytic Anaplasma.
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Affiliation(s)
- Ala E Lew
- Department of Primary Industries, Agency for Food and Fibre Sciences, c/o Animal Research Institute, 665 Fairfield Rd., Locked Mail Bag No. 4, Yeerongpilly, Moorooka, Queensland 4105, Australia.
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33
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Meeus PFM, Brayton KA, Palmer GH, Barbet AF. Conservation of a gene conversion mechanism in two distantly related paralogues of Anaplasma marginale. Mol Microbiol 2003; 47:633-43. [PMID: 12535066 DOI: 10.1046/j.1365-2958.2003.03331.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Anaplasmataceae, the causative agents of anaplasmosis and ehrlichiosis, persist in the bloodstream of their mammalian hosts, allowing acquisition and transmission by tick vectors. Anaplasma marginale establishes persistent infection characterized by sequential cycles of rickettsaemia in which new antigenic variants emerge. The two most immunodominant outer membrane proteins, MSP2 and MSP3, are paralogues, each encoded by a distinct family of related genes. This study demonstrates that, although the two gene families have diverged substantially, each has maintained a similar mechanism to generate structurally and antigenically polymorphic surface antigens. Like MSP2, MSP3 is expressed from a single locus in which variation of the expressed msp3 gene is generated by recombination using msp3 pseudogenes. Each of the msp3 pseudogenes encodes a unique central variable region (CVR) flanked by conserved 5' and 3' regions. Changes in the CVR of the expressed msp3, concomitant with invariance of the pseudogenes, indicate that expression site variation is generated using gene conversion. A. marginale thus maintains two large, separate systems within its small genome to generate antigenic variation of its surface proteins, while analogous structural elements indicate a common mechanism.
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Affiliation(s)
- Patrick F M Meeus
- Department of Pathobiology, College of Veterinary Medicine, University of Florida, 2015 SW 16th Avenue, Gainesville, FL 32611-0880, USA.
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de la Fuente J, Van Den Bussche RA, Garcia-Garcia JC, Rodríguez SD, García MA, Guglielmone AA, Mangold AJ, Friche Passos LM, Barbosa Ribeiro MF, Blouin EF, Kocan KM. Phylogeography of New World isolates of Anaplasma marginale based on major surface protein sequences. Vet Microbiol 2002; 88:275-85. [PMID: 12151201 DOI: 10.1016/s0378-1135(02)00122-0] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Gene and protein sequences of major surface proteins (MSP) 1a and 4 of Anaplasma marginale (Rickettsiales: Anaplasmataceae) were used to infer phylogenetic relationships between New World isolates from Argentina, Brazil, Mexico and the United States. Seventeen isolates of A. marginale plus two outgroup taxa (A. centrale and A. ovis) were used for maximum-parsimony analysis of MSP4, while 20 isolates were used for phylogenetic analysis of MSP1a. msp4 analysis provided strong bootstrap support for a Latin American clade and, within this clade, support was detected for Mexican and South American clades. Isolates of A. marginale from the United States also grouped into two clades from the southern (isolates from Florida, Mississippi, and Virginia) and west-central (isolates from California, Idaho, Illinois, Oklahoma, and Texas) states. Although little phylogeographic resolution was detected within these higher clades, msp4 sequences appear to be a good genetic marker for inferring phylogeographic patterns of A. marginale isolates. In contrast to the phylogeographic resolution provided by msp4, MSP1a DNA and protein sequence were quite variable and did not provide phylogeographic resolution. Most variation in MSP1a sequences appeared unique to a given isolate and similar DNA sequence variation in msp1alpha was detected within isolates from Idaho and Florida and from Idaho and Argentina. The results of these studies demonstrated that msp4 provided phylogenetic information on the evolution of A. marginale isolates. In contrast MSP1a sequences appeared to be rapidly evolving and these sequences may provide phylogeographic information only when numerous isolate MSP1a sequences are analyzed from a geographic area.
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Affiliation(s)
- José de la Fuente
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, 250 McElroy Hall, Stillwater, OK 74078, USA.
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35
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de la Fuente J, Garcia-Garcia JC, Blouin EF, Saliki JT, Kocan KM. Infection of tick cells and bovine erythrocytes with one genotype of the intracellular ehrlichia Anaplasma marginale excludes infection with other genotypes. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2002; 9:658-68. [PMID: 11986275 PMCID: PMC119989 DOI: 10.1128/cdli.9.3.658-668.2002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2001] [Revised: 12/14/2001] [Accepted: 01/22/2002] [Indexed: 11/20/2022]
Abstract
Anaplasma marginale, a tick-borne rickettsial pathogen of cattle, is endemic in several areas of the United States. Many geographic isolates of A. marginale that occur in the United States are characterized by the major surface protein 1a, which varies in sequence and molecular weight due to different numbers of tandem repeats of 28 or 29 amino acids. Recent studies (G. H. Palmer, F. R. Rurangirwa, and T. F. McElwain, J. Clin. Microbiol. 39:631-635, 2001) of an A. marginale-infected herd of cattle in an area of endemicity demonstrated that multiple msp1alpha genotypes were present but that only one genotype was found per individual bovine. These findings suggested that infection of cattle with other genotypes was excluded. The present study was undertaken to confirm the phenomenon of infection exclusion of A. marginale genotypes in infected bovine erythrocytes and cultured tick cells. Two tick-transmissible isolates of A. marginale, one from Virginia and one from Oklahoma, were used for these studies. In two separate trials, cattle inoculated with equal doses of the two isolates developed infection with only one genotype. Tick cell cultures inoculated with equal doses of the two isolates became infected with only the Virginia isolate of A. marginale. When cultures were inoculated with different ratios of the Oklahoma and Virginia isolates of A. marginale, the isolate inoculated in the higher ratio became established and excluded infection with the other. When cultures with established infections of one isolate were subsequently infected with the other, only the established isolate was detected. We documented infection exclusion during initial infection in cell culture by labeling each isolate with a different fluorescent dye. After 2 days in culture, only a single isolate was detected per cell by fluorescence microscopy. Finally, when Anaplasma ovis infections were established in cultures that were subsequently inoculated with the Virginia or Oklahoma isolate of A. marginale, A. marginale infection was excluded. These studies confirm that infection exclusion occurs with A. marginale in bovine erythrocytes and tick cells, resulting in the establishment of only one genotype, and appears to be the first report of infection exclusion for Anaplasma and Ehrlichia species.
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Affiliation(s)
- José de la Fuente
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, Stillwater, Oklahoma 74078, USA.
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36
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Bekker CPJ, Bell-Sakyi L, Paxton EA, Martinez D, Bensaid A, Jongejan F. Transcriptional analysis of the major antigenic protein 1 multigene family of Cowdria ruminantium. Gene 2002; 285:193-201. [PMID: 12039046 DOI: 10.1016/s0378-1119(02)00408-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The major antigenic protein 1 (MAP1) of the tick-borne rickettsial pathogen Cowdria ruminantium is encoded by a multigene family containing conserved and variable genes. The part of a locus containing the map1 multigene family that was characterized contained three homologous, but non-identical map1 genes, designated map1-2, map1-1, and map1. Reverse transcriptase-polymerase chain reaction was used to study the transcriptional activity of these genes in isolates of C. ruminantium grown in bovine endothelial cells, in two different tick cell lines, and in Amblyomma variegatum ticks. The map1 gene was always transcribed, whereas transcription of map1-2 was not detected under any of the tested conditions. The map1-1 gene transcript was detected in A. variegatum ticks, but was not found in virulent C. ruminantium Senegal grown in bovine endothelial cells at 30 or 37 degrees C. Interestingly, transcripts of map1-1 were also found in different passages of the in vitro attenuated Senegal isolate grown in bovine endothelial cells, as well as in the Gardel isolate grown in two tick cell lines. When transcribed, map1-1 was present on a polycistronic messenger together with map1.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigens, Bacterial
- Bacterial Outer Membrane Proteins/genetics
- Cattle
- Cell Line
- Cells, Cultured
- Cloning, Molecular
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- Ehrlichia ruminantium/genetics
- Endothelium, Vascular/cytology
- Endothelium, Vascular/microbiology
- Molecular Sequence Data
- Multigene Family/genetics
- RNA, Bacterial/genetics
- RNA, Bacterial/metabolism
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Ticks/cytology
- Ticks/microbiology
- Transcription, Genetic
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Affiliation(s)
- Cornelis P J Bekker
- Division of Bacteriology, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Box 80165, 3508 TD, Utrecht, The Netherlands
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37
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Abstract
Study of microbial genomes has provided new insight into the functions that pathogens require for survival in the animal host. Small genome bacterial pathogens, defined as those < or = 1/3 the size of Escherichia coli, include chlamydiae, rickettsiae and ehrlichiae, mycoplasmas, and spirochetes. The small genome size is believed to result from reductive evolution, a process of initial mutation with loss of function followed by progressive accumulation of mutations and eventual gene deletion. This is most notable in the 1.1 Mb genome of Rickettsia prowazekki in which 24% of the genome is non-coding, as compared to approximately 10% in the 4.4 Mb E. coli. Consequently, these pathogens are thus presumed to retain only the most important functions for survival and propagation. There is consistent evidence from small genomes that the genetic deletion is primarily related to the loss of metabolic function and especially reduction of multiple overlapping pathways and duplicated genes. Thus, these pathogens undergo progressive reduction in their genomes yet maintain the ability to infect, survive within, and cause disease in animals. In the face of this reductive process, what genes and associated functions are maintained? Strikingly, these pathogens devote a high percentage of their genomes to paralogous families of polymorphic surface molecules. This retention suggests that evasion of the immune response is the highest priority of obligate microbial pathogens and provides a strategy for identifying protective antigens for vaccine development to control disease.
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Affiliation(s)
- Guy H Palmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
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Shkap V, Molad T, Brayton KA, Brown WC, Palmer GH. Expression of major surface protein 2 variants with conserved T-cell epitopes in Anaplasma centrale vaccinates. Infect Immun 2002; 70:642-8. [PMID: 11796593 PMCID: PMC127678 DOI: 10.1128/iai.70.2.642-648.2002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Major surface protein 2 (MSP-2), identified as a protection-inducing immunogen against Anaplasma marginale challenge, is an immunodominant outer membrane protein with orthologues in all examined Anaplasma species. Although immunization with live Anaplasma centrale has long been used to induce protection against acute disease upon challenge with virulent A. marginale, its MSP-2 structure and whether MSP-2 variants are generated during persistence of the vaccine strain was unknown. In this study, we showed that the A. centrale vaccine strain persisted for a minimum of 4 years postvaccination and generated sequential MSP-2 variants. Comparison of amino acid sequences encoded by A. centrale msp-2 transcripts from the initial postimmunization period and from sequential time points during persistence of the vaccine strain revealed a central hypervariable domain flanked by conserved amino and carboxy-terminal regions. This structure corresponded to that shown in A. marginale MSP-2, where the central hypervariable region encodes variant B-cell epitopes in the extracellular domain and the flanking transmembrane domains are rich in CD4(+)-T-cell epitopes. Importantly, at least four CD4(+)-T-cell epitopes are conserved between the two species, a finding consistent with A. marginale challenge triggering a recall response of CD4(+) T cells induced by A. centrale vaccination. The genomic arrangement is conserved between A. centrale and A. marginale with multiple msp-2 pseudogenes and a single operon-linked expression site for the full-length msp-2. This conservation of both genomic structure for generating MSP-2 variants and the CD4(+)-T-cell epitopes between these two genetically distinct Anaplasma species indicates that they present a similar repertoire of MSP-2 epitopes to the immune system and that this similarity may be responsible for all or part of the A. centrale vaccine efficacy.
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Affiliation(s)
- Varda Shkap
- Department of Parasitology, Kimron Veterinary Institute, Bet Dagan, Israel
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39
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Inokuma H, Terada Y, Kamio T, Raoult D, Brouqui P. Analysis of the 16S rRNA gene sequence of Anaplasma centrale and its phylogenetic relatedness to other ehrlichiae. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 2001; 8:241-4. [PMID: 11238202 PMCID: PMC96043 DOI: 10.1128/cdli.8.2.241-244.2001] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The nucleotide sequence of the Anaplasma centrale 16S rRNA gene was determined and compared with the sequences of ehrlichial bacteria. The sequence of A. centrale was closely related to Anaplasma marginale by both level-of-similarity (98.08% identical) and distance analysis. A species-specific PCR was developed based upon the alignment data. The PCR can detect A. centrale DNA extracted from 10 infected bovine red blood cells in a reaction mixture. A. centrale DNA was amplified in the reaction, but not other related ehrlichial species.
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Affiliation(s)
- H Inokuma
- Faculty of Agriculture, Yamaguchi University, Yamaguchi 753-8515, Japan
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40
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Palmer GH, Rurangirwa FR, McElwain TF. Strain composition of the ehrlichia Anaplasma marginale within persistently infected cattle, a mammalian reservoir for tick transmission. J Clin Microbiol 2001; 39:631-5. [PMID: 11158120 PMCID: PMC87789 DOI: 10.1128/jcm.39.2.631-635.2001] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tick-borne ehrlichial pathogens of animals and humans require a mammalian reservoir of infection from which ticks acquire the organism for subsequent transmission. In the present study, we examined the strain structure of Anaplasma marginale, a genogroup II ehrlichial pathogen, in both an acute outbreak and in persistently infected cattle that serve as a reservoir for tick transmission. Using the msp1alpha genotype as a stable strain marker, only a single genotype was detected in a disease outbreak in a previously uninfected herd. In contrast, a diverse set of genotypes was detected in a persistently infected reservoir herd within a region where A. marginale is endemic. Genotypic diversity did not appear to be rapidly generated within an individual animal, because only a single genotype, identical to that of the inoculating strain, was detected at time points up to 2 years after experimental infection, and only a single identical genotype was found in repeat sampling of individual naturally infected cattle. Similarly, only a single genotype, identical to that of the experimentally inoculated St. Maries or South Idaho strain, was identified in the bloodmeal taken by Dermacentor andersoni ticks, in the midgut and salivary glands of the infected ticks, and in the blood of acutely infected cattle following tick transmission. The results show that mammalian reservoirs harbor genetically heterogeneous A. marginale and suggest that different genotypes are maintained by transmission within the reservoir population.
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Affiliation(s)
- G H Palmer
- Program in Vector-borne Diseases, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164-7040, USA.
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41
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Brown WC, McGuire TC, Zhu D, Lewin HA, Sosnow J, Palmer GH. Highly conserved regions of the immunodominant major surface protein 2 of the genogroup II ehrlichial pathogen Anaplasma marginale are rich in naturally derived CD4+ T lymphocyte epitopes that elicit strong recall responses. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:1114-24. [PMID: 11145692 DOI: 10.4049/jimmunol.166.2.1114] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Genogroup II ehrlichia, including the agent of human granulocytic ehrlichiosis, Ehrlichia phagocytophila, and the bovine pathogen Anaplasma marginale, express a markedly immunodominant outer membrane protein designated major surface protein 2 (MSP2). MSP2 is encoded by a multigene family, resulting in the expression of variant B cell epitopes. MSP2 variants are sequentially expressed in the repeated cycles of rickettsemia that characterize persistent A. marginale infection and control of each rickettsemic cycle is associated with development of a variant-specific IgG response. Importantly, these persistent rickettsemic cycles are controlled at levels 100-1000 times lower than those responsible for clinical disease during acute infection. Control of rickettsemia during persistence could result from an anamnestic Th lymphocyte response to conserved regions of MSP2 that enhances the primary Ab response against newly emergent variants. Comparison of MSP2 variants reveals conserved N and C termini flanking the central, surface-exposed hypervariable region that represents the variant B lymphocyte epitopes. We demonstrate MSP2-specific CD4(+) T lymphocyte recognition of epitopes common to several strains of A. marginale and the related pathogen A. ovis. Furthermore, T lymphocyte lines from three individuals identified six to nine overlapping peptides representing a minimum of four to seven dominant or subdominant epitopes in these conserved N and C termini. Immunodominant peptides induced high levels of IFN-gamma, a cytokine associated with protection against ehrlichia and needed for rapid generation of variant-specific IgG2. The presented data support the potential importance of a strong Th lymphocyte response to invariant MSP2 epitopes in controlling rickettsemia during persistent infection to subclinical levels.
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Affiliation(s)
- W C Brown
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
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Yu X, McBride JW, Zhang X, Walker DH. Characterization of the complete transcriptionally active ehrlichia chaffeensis 28 kDa outer membrane protein multigene family. Gene 2000; 248:59-68. [PMID: 10806351 DOI: 10.1016/s0378-1119(00)00147-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The 28kDa outer membrane proteins (P28) of Ehrlichia chaffeensis are encoded by a multigene family. The purpose of this study was to determine all the p28 gene sequences and their transcriptional activities. There were 21 members of the p28 multigene family located in a 23kb DNA fragment in the genome of E. chaffeensis. The p28 genes each contained 816-903 nucleotides with intergenic spaces of 10-605 nucleotides. All the genes were complete and were predicted to have a signal sequence. The molecular masses of the mature proteins were predicted to be 28-32kDa. The amino acid sequence identity of the P28 proteins was 20-83%. Ten p28 genes were investigated for transcriptional activity by using RT-PCR amplification of mRNA. Six of 10 tested p28 genes were actively transcribed in cell-culture grown E. chaffeensis. RT-PCR also indicated that each of the p28 genes was monocistronic. These results suggest that the p28 genes are active genes and encode polymorphic forms of the P28 proteins. The P28s were divergent among isolates of E. chaffeensis also. The large repertoire of the p28 genes in a single ehrlichial organism and antigenic diversity of the P28 among the isolates of E. chaffeensis suggest that P28s may be involved in immune avoidance.
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Affiliation(s)
- X Yu
- Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch, Galveston, TX 77555-0609, USA.
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Palmer GH, Brown WC, Rurangirwa FR. Antigenic variation in the persistence and transmission of the ehrlichia Anaplasma marginale. Microbes Infect 2000; 2:167-76. [PMID: 10742689 DOI: 10.1016/s1286-4579(00)00271-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tick-borne transmission of ehrlichial pathogens requires rickettsemic reservoir hosts to maintain a population of infected vectors. Persistence in their respective mammalian hosts appears to be a common feature of the tick-transmitted ehrlichiae. How infection persists in immunocompetent hosts is unknown. In this review, we describe studies on Anaplasma marginale, an ehrlichial pathogen of cattle, that support antigenic variation as a primary mechanism of persistence.
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Affiliation(s)
- G H Palmer
- Program in Vector-Borne Diseases, Washington State University, Pullman, WA 99164-7040, USA
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Abstract
Several pathogens of humans and domestic animals depend on hematophagous arthropods to transmit them from one vertebrate reservoir host to another and maintain them in an environment. These pathogens use antigenic variation to prolong their circulation in the blood and thus increase the likelihood of transmission. By convergent evolution, bacterial and protozoal vector-borne pathogens have acquired similar genetic mechanisms for successful antigenic variation. Borrelia spp. and Anaplasma marginale (among bacteria) and African trypanosomes, Plasmodium falciparum, and Babesia bovis (among parasites) are examples of pathogens using these mechanisms. Antigenic variation poses a challenge in the development of vaccines against vector-borne pathogens.
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Affiliation(s)
- A G Barbour
- University of California Irvine, Irvine, California 92697-4025, USA.
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Palmer GH, Rurangirwa FR, Kocan KM, Brown WC. Molecular basis for vaccine development against the ehrlichial pathogen Anaplasma marginale. PARASITOLOGY TODAY (PERSONAL ED.) 1999; 15:281-6. [PMID: 10377531 DOI: 10.1016/s0169-4758(99)01469-6] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Anaplasma marginale is a tick-transmitted ehrlichial pathogen causing severe morbidity and mortality in livestock on six continents. Development of safe effective vaccines would be greatly facilitated by identification of the protective immune mechanisms and by understanding how the pathogen evades immune effectors to establish persistent infection. In this article, Guy Palmer and colleagues review recent progress in identifying how defined epitopes induce protective immunity and the role of antigenic variation in these epitopes as a mechanism of persistence.
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Affiliation(s)
- G H Palmer
- Program in Vector-borne Diseases, Washington State University, Pullman, WA 99164-7040, USA.
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Sulsona CR, Mahan SM, Barbet AF. The map1 gene of Cowdria ruminantium is a member of a multigene family containing both conserved and variable genes. Biochem Biophys Res Commun 1999; 257:300-5. [PMID: 10198207 DOI: 10.1006/bbrc.1999.0459] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Heartwater is an economically important disease of ruminants caused by the tick-transmitted rickettsia Cowdria ruminantium. The disease is present in Africa and the Caribbean and there is a risk of spread to the Americas, particularly because of a clinically asymptomatic carrier state in infected livestock and imported wild animals. The causative agent is closely related taxonomically to the human and animal pathogens Ehrlichia chaffeensis and Ehrlichia canis. A dominant immune response of infected animals or people is directed against variable outer membrane proteins of these agents known, in E. chaffeensis and E. canis, to be encoded by polymorphic multigene families. We demonstrate, by sequence analysis, that map1 encoding the major outer membrane protein of C. ruminantium is also encoded by a polymorphic multigene family. Two members of the gene family are located in tandem in the genome. The upstream member, orf2, is conserved, encoding only 2 amino acid substitutions among six different rickettsial strains from diverse locations in Africa and the Caribbean. In contrast, the downstream member, map1, contains variable and conserved regions between strains. Interestingly, orf2 is more closely related in sequence to omp1b of E. chaffeensis than to map1 of C. ruminantium. The regions that differ among orf2, map1, and omp1b correspond to previously identified variable sequences in outer membrane protein genes of E. chaffeensis and E. canis. These data suggest that diversity in these outer membrane proteins may arise by recombination among gene family members and offer a potential mechanism for persistence of infection in carrier animals.
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Affiliation(s)
- C R Sulsona
- Department of Pathobiology, College of Veterinary Medicine, Gainesville, Florida, 32611, USA
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Brown WC, Shkap V, Zhu D, McGuire TC, Tuo W, McElwain TF, Palmer GH. CD4(+) T-lymphocyte and immunoglobulin G2 responses in calves immunized with Anaplasma marginale outer membranes and protected against homologous challenge. Infect Immun 1998; 66:5406-13. [PMID: 9784551 PMCID: PMC108677 DOI: 10.1128/iai.66.11.5406-5413.1998] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/1998] [Accepted: 09/04/1998] [Indexed: 11/20/2022] Open
Abstract
Protective immunity against the ehrlichial pathogen Anaplasma marginale has been hypothesized to require induction of immunoglobulin G2 (IgG2) antibody against outer membrane protein epitopes and coordinated activation of macrophages for phagocytosis and killing. In the present study, cell-mediated immune responses, including induction of IgG isotype switching, were characterized in calves immunized with purified outer membranes of the Florida strain of A. marginale. Importantly, these calves were subsequently shown to be protected upon experimental challenge with the Florida strain, and calves which developed the highest IgG2 titers were completely protected against infection. Peripheral blood mononuclear cells (PBMC) obtained after immunization proliferated strongly in response to both whole A. marginale homogenates and purified outer membranes, and this responsiveness persisted until the time of challenge. Responding cells were shown to be CD4(+) T cells, and CD4(+) T-cell lines cultured for 2 to 4 weeks also proliferated specifically in response to A. marginale and produced high titers of gamma interferon. The helper T-cell response included recognition of conserved epitopes, as PBMC proliferation was stimulated by the homologous Florida strain, four genetically distinct A. marginale strains, and Anaplasma ovis. The outer membrane proteins stimulating the PBMC responses in protected calves included major surface proteins (MSPs) MSP-1, MSP-2, and MSP-3, which were previously shown to induce partial protection against infection. These studies demonstrate, for the first time, potent helper T-cell responses in cattle protectively immunized with outer membranes against A. marginale challenge and identify three MSPs that are recognized by immune T cells. These experiments provide the basis for subsequent identification of the helper T-cell epitopes on MSP-1, MSP-2, and MSP-3 that are needed to evoke anamnestic antibody and effector T-cell responses elicited by protein or nucleic acid immunization.
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Affiliation(s)
- W C Brown
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164, USA.
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