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Assessment of the Impact of Early Diagnosis and Early Treatment in the Integrated Control of East Coast Fever (ECF) Involving Acquired Immunity Induced by Natural Infection in Ankole Cattle. Pathogens 2023; 12:pathogens12010115. [PMID: 36678463 PMCID: PMC9864176 DOI: 10.3390/pathogens12010115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 01/04/2023] [Accepted: 01/07/2023] [Indexed: 01/12/2023] Open
Abstract
The integrated control of East Coast fever (ECF) by early diagnosis and treatment involving acquired immunity induced by natural infection in Ankole cattle was assessed. A longitudinal study was carried out in Kiruhura district, southwestern Uganda for six months on 244 Ankole breed of cattle from 18 herds under natural tick challenge and relaxed tick control measures. Calves aged three to six months old were recruited and monitored daily by farmers for detection of ECF clinical symptoms. The reported sick animals were treated using Buparvaquone and treatment outcome determined. Monthly follow-ups and blood collections were done to monitor ECF status. Blood was analyzed for Theileria parva parasites by microscopy, DNA by polymerase chain reaction (PCR) and antibodies by enzyme-linked immunosorbent assay (ELISA). The overall prevalence of ECF clinical disease within six months period was 30.3% (74). The major symptoms of early clinical ECF disease were fever and enlarged parotid or prescapular lymph nodes. Clinical cases were categorized as mild, 24% (18) or moderate, 76% (56). There was an overall recovery rate of 100% (74) of the ECF cases whereby 94.6% (70) recovered promptly and 5.4% (4) recovered slowly. Based on blood analysis, prevalence of ECF at baseline was 3.7% (9) by microscopy, 31.1% (76) by PCR and 38.1% (93) by ELISA. A significant increase (p < 0.05) was shown by the increased number of calves with T. parva specific antibodies in the sera from 38.1% at baseline to 68.8% after six months. High antibody levels (positive percentage ≥ 50%) were detected in all ECF-treated and recovered calves at the end of six months. The acquired immunity to ECF was high in treated and recovered cattle, indicating that natural exposure to infection, accurate early diagnosis and effective treatment enhance development of immune-protection in indigenous cattle in an endemic area. The prominent early clinical symptoms for ECF could be exploited in the development of decision support tools for chemotherapy and other integrated control measures.
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Agina OA, Shaari MR, Isa NMM, Ajat M, Zamri-Saad M, Hamzah H. Clinical Pathology, Immunopathology and Advanced Vaccine Technology in Bovine Theileriosis: A Review. Pathogens 2020; 9:E697. [PMID: 32854179 PMCID: PMC7558346 DOI: 10.3390/pathogens9090697] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/15/2020] [Accepted: 07/16/2020] [Indexed: 01/29/2023] Open
Abstract
Theileriosis is a blood piroplasmic disease that adversely affects the livestock industry, especially in tropical and sub-tropical countries. It is caused by haemoprotozoan of the Theileria genus, transmitted by hard ticks and which possesses a complex life cycle. The clinical course of the disease ranges from benign to lethal, but subclinical infections can occur depending on the infecting Theileria species. The main clinical and clinicopathological manifestations of acute disease include fever, lymphadenopathy, anorexia and severe loss of condition, conjunctivitis, and pale mucous membranes that are associated with Theileria-induced immune-mediated haemolytic anaemia and/or non-regenerative anaemia. Additionally, jaundice, increases in hepatic enzymes, and variable leukocyte count changes are seen. Theileria annulata and Theileria parva induce an incomplete transformation of lymphoid and myeloid cell lineages, and these cells possess certain phenotypes of cancer cells. Pathogenic genotypes of Theileria orientalis have been recently associated with severe production losses in Southeast Asia and some parts of Europe. The infection and treatment method (ITM) is currently used in the control and prevention of T. parva infection, and recombinant vaccines are still under evaluation. The use of gene gun immunization against T. parva infection has been recently evaluated. This review, therefore, provides an overview of the clinicopathological and immunopathological profiles of Theileria-infected cattle and focus on DNA vaccines consisting of plasmid DNA with genes of interest, molecular adjuvants, and chitosan as the most promising next-generation vaccine against bovine theileriosis.
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Affiliation(s)
- Onyinyechukwu Ada Agina
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, University of Nigeria Nsukka, Nsukka 410001, Nigeria
| | - Mohd Rosly Shaari
- Animal Science Research Centre, Malaysian Agricultural Research and Development Institute, Headquarters, Serdang 43400, Malaysia;
| | - Nur Mahiza Md Isa
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Mokrish Ajat
- Department of Veterinary Pre-clinical sciences, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Mohd Zamri-Saad
- Research Centre for Ruminant Diseases, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
| | - Hazilawati Hamzah
- Department of Veterinary Pathology and Microbiology, Faculty of Veterinary Medicine, Universiti Putra Malaysia, Serdang 43400, Malaysia;
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Silatsa BA, Simo G, Githaka N, Kamga R, Oumarou F, Keambou Tiambo C, Machuka E, Domelevo JB, Odongo D, Bishop R, Kuiate JR, Njiokou F, Djikeng A, Pelle R. First detection of Theileria parva in cattle from Cameroon in the absence of the main tick vector Rhipicephalus appendiculatus. Transbound Emerg Dis 2020; 67 Suppl 1:68-78. [PMID: 32174039 PMCID: PMC7216920 DOI: 10.1111/tbed.13425] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A major risk factor for the spread of livestock diseases and their vectors is the uncontrolled transboundary movement of live animals for trade and grazing. Such movements constrain effective control of tick-transmitted pathogens, including Theileria parva. Only limited studies have been undertaken to identify ticks and tick-borne diseases (TTBDs) affecting cattle in central African countries, including Cameroon. We hereby report the collection of baseline data on the prevalence of T. parva in Cameroon through a countrywide cross-sectional survey, conducted in 2016, involving collection of blood samples from cattle from 63 sites across the five agro-ecological zones (AEZs) of the country. ELISA-based surveillance of infected cattle was performed on 479 randomly selected samples and revealed specific antibodies to T. parva in 22.7% and T. mutans in 41.1% of cattle. Screening of 1,340 representative DNA samples for the presence of T. parva identified 25 (1.86%) positives using a p104 antigen gene-based nested PCR assay. The positives were distributed across agro-ecological zones I, II, III and V. None of the p104 positive cattle exhibited clinical symptoms of East Coast fever (ECF). Using reverse line blot (RLB), 58 (4.3%) and 1,139 (85%) of the samples reacted with the T. parva and T. mutans oligonucleotide probes, respectively. This represents the first report of T. parva from Cameroon. Surprisingly, no Rhipicephalus appendiculatus ticks, the main vector of T. parva, were identified in a parallel study involving comprehensive morphological and molecular survey of tick species present in the country. Only two of the 25 p104 positive cattle were PCR-positive for the CD8+ T-cell target schizont-expressed antigen gene Tp1. Cloning and sequencing of Tp1 amplicons revealed sequence identity with the reference T. parva Muguga. This new finding raises serious concerns of a potential spread of ECF into the central African region.
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Affiliation(s)
- Barberine A Silatsa
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Gustave Simo
- Molecular Parasitology and Entomology Unit, Department of Biochemistry, Faculty of Sciences, University of Dschang, Dschang, Cameroon
| | - Naftaly Githaka
- Department of Biosciences, International Livestock Research Institute (ILRI), Nairobi, Kenya
| | - Rolin Kamga
- Molecular Parasitology and Entomology Unit, Department of Biochemistry, Faculty of Sciences, University of Dschang, Dschang, Cameroon
| | - Farikou Oumarou
- Special Mission for Eradication of Tsetse Flies, Regional tsetse Division of Adamawa, MINEPIA, Adamawa, Cameroon
| | - Christian Keambou Tiambo
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Eunice Machuka
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Jean-Baka Domelevo
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - David Odongo
- School of Biological Sciences, University of Nairobi, Nairobi, Kenya
| | - Richard Bishop
- Veterinary Microbiology and Pathology (VMP), Washington State University, Pullman, WA, USA
| | - Jules-Roger Kuiate
- Department of Biochemistry, Faculty of Sciences, University of Dschang, Dschang, Cameroon
| | - Flobert Njiokou
- Laboratory of General Biology, Faculty of Sciences, University of Yaounde I, Yaounde, Cameroon
| | - Appolinaire Djikeng
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
| | - Roger Pelle
- Biosciences Eastern and Central Africa - International Livestock Research Institute (BecA-ILRI) Hub, Nairobi, Kenya
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Patel E, Mwaura S, Di Giulio G, Cook EAJ, Lynen G, Toye P. Infection and treatment method (ITM) vaccine against East Coast fever: reducing the number of doses per straw for use in smallholder dairy herds by thawing, diluting and refreezing already packaged vaccine. BMC Vet Res 2019; 15:46. [PMID: 30704455 PMCID: PMC6357393 DOI: 10.1186/s12917-019-1787-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 01/17/2019] [Indexed: 11/23/2022] Open
Abstract
Background The Infection and Treatment Method (ITM) of vaccination is the only immunization procedure currently available to protect cattle against East Coast fever (ECF), a tick-transmitted disease responsible for losses of several hundreds of millions of dollars per year in sub-Saharan Africa. The vaccine comprises a homogenized preparation of infected ticks packaged in straws and stored in liquid nitrogen. The current manufacturing protocol results in straws containing 30–40 doses (ILRI 0804), which is impractical for immunizing small herds as found in dairy and smallholder farming systems. The ILRI 0804 SD stabilate was prepared as a 1:5 dilution of the parent stabilate, with the aim of producing vaccine stabilate straws containing between four to eight doses and thus suitable for smallholder farming systems. Infectivity of the diluted stabilate was assessed and the protective efficacy of the diluted stabilate was determined by performing experimental and field immunizations. Results Two groups of six cattle were inoculated with 1 ml of the diluted stabilate at 1:20 (equivalent to the recommended field dose for ILRI 0804, assuming no loss of sporozoite viability during thawing and refreezing) and 1:14 (assuming 30–35% loss of sporozoite viability). Schizonts were detected in all 12 animals, showing viability of sporozoites. Ten animals from the infectivity study and two control animals not previously exposed to T. parva were challenged with the parental ILRI 0804 stabilate. The results show that the two control animals displayed severe ECF reactions and were treated 14 days after challenge. Of the previously infected animals, only one underwent a severe reaction following challenge, a result in accord with the challenge experiments performed previously with the parent stabilate [Ticks Tick-Borne Dis 7:306-314, 2016]. The animal that displayed a severe reaction had no detectable schizonts and did not seroconvert following the initial inoculation with ILRI 0804 SD. In addition, 62 animals immunized under field conditions showed a mean seroconversion rate of 82%. Conclusion The results presented in this article demonstrate that it is possible to prepare straws suitable for use in smallholder herds by thawing, diluting and refreezing already packaged vaccine.
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Affiliation(s)
- Ekta Patel
- International Livestock Research Institute, P.O.Box 30709-00100, Old Naivasha Road, Nairobi, Kenya.
| | - Stephen Mwaura
- International Livestock Research Institute, P.O.Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
| | | | - Elizabeth A J Cook
- International Livestock Research Institute, P.O.Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
| | - Godelieve Lynen
- International Livestock Research Institute, P.O.Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
| | - Philip Toye
- International Livestock Research Institute, P.O.Box 30709-00100, Old Naivasha Road, Nairobi, Kenya.
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Patel E, Mwaura S, Kiara H, Morzaria S, Peters A, Toye P. Production and dose determination of the Infection and Treatment Method (ITM) Muguga cocktail vaccine used to control East Coast fever in cattle. Ticks Tick Borne Dis 2015; 7:306-14. [PMID: 26698194 DOI: 10.1016/j.ttbdis.2015.11.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 11/07/2015] [Accepted: 11/24/2015] [Indexed: 11/28/2022]
Abstract
The Infection and Treatment Method (ITM) of vaccination against the apicomplexan parasite Theileria parva has been used since the early 1970s and is still the only commercially available vaccine to combat the fatal bovine disease, East Coast fever (ECF). The disease is tick-transmitted and results in annual economic losses of at least $300 million per year. While this vaccine technology has been available for over 40 years, few attempts have been made to standardize the production process and characterize the vaccine. The latest batch was produced in early 2008 at the International Livestock Research Institute (ILRI). The vaccine production involves the use of cattle free from parasites routinely monitored throughout the production process, and a pathogen-free tick colony. This paper describes the protocol used in the recent production, and the process improvements, including improved quality control tools, that had not been employed in previous ITM productions. The paper also describes the processes involved in determining the appropriate field dose, which involved a three-step in vivo study with various dilutions of the vaccine stabilate. The vaccine was shown to be safe and viable after production, and a suitable field dose was identified as 1 ml of a 1:100 dilution.
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Affiliation(s)
- Ekta Patel
- International Livestock Research Institute, P.O. Box 30709-00100, Old Naivasha Road, Nairobi, Kenya.
| | - Stephen Mwaura
- International Livestock Research Institute, P.O. Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
| | - Henry Kiara
- International Livestock Research Institute, P.O. Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
| | - Subhash Morzaria
- Senior Animal Health Adviser, Emergency Centre for Transboundary Animal Diseases, Food and Agriculture Organization of the United Nations, Viale Delle Terme di Caracalla, 00153 Rome, Italy
| | - Andrew Peters
- Scotland's Rural College, King's Buildings, Edinburgh EH9 3JG, UK
| | - Philip Toye
- International Livestock Research Institute, P.O. Box 30709-00100, Old Naivasha Road, Nairobi, Kenya
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Mans BJ, Pienaar R, Latif AA. A review of Theileria diagnostics and epidemiology. INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2015; 4:104-18. [PMID: 25830110 PMCID: PMC4356873 DOI: 10.1016/j.ijppaw.2014.12.006] [Citation(s) in RCA: 169] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 11/28/2022]
Abstract
Serological and molecular assays exist for most economic important Theileria species. Molecular assays are constantly being improved with regard to sensitivity and specificity. The concept of what constitute a Theileria species impacts on accurate diagnostics. Analytical specificity of molecular assays are >800 000 parasites/L blood. Parasitemia ranges may determine practical limits of detection.
An extensive range of serological and molecular diagnostic assays exist for most of the economically important Theileira species such as T. annulata, T. equi, T. lestoquardi, T. parva, T. uilenbergi and other more benign species. Diagnostics of Theileria is considered with regard to sensitivity and specificity of current molecular and serological assays and their use in epidemiology. In the case of serological assays, cross-reactivity of genetically closely related species reduces the use of the gold standard indirect fluorescent antibody test (IFAT). Development of antigen-specific assays does not necessarily address this problem, since closely related species will potentially have similar antigens. Even so, serological assays remain an important line of enquiry in epidemiological surveys. Molecular based assays have exploded in the last decade with significant improvements in sensitivity and specificity. In this review, the current interpretation of what constitute a species in Theileria and its impact on accurate molecular diagnostics is considered. Most molecular assays based on conventional or real-time PCR technology have proven to be on standard with regard to analytical sensitivity. However, consideration of the limits of detection in regard to total blood volume of an animal indicates that most assays may only detect >400,000 parasites/L blood. Even so, natural parasitaemia distribution in carrier-state animals seems to be above this limit of detection, suggesting that most molecular assays should be able to detect the majority of infected individuals under endemic conditions. The potential for false-negative results can, however, only be assessed within the biological context of the parasite within its vertebrate host, i.e. parasitaemia range in the carrier-state that will support infection of the vector and subsequent transmission.
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Affiliation(s)
- Ben J Mans
- Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa ; The Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa ; Department of Life and Consumer Sciences, University of South Africa, South Africa
| | - Ronel Pienaar
- Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa
| | - Abdalla A Latif
- Parasites, Vectors and Vector-Borne Diseases, Agricultural Research Council-Onderstepoort Veterinary Institute, Onderstepoort 0110, South Africa ; The Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
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A longitudinal assessment of the serological response to Theileria parva and other tick-borne parasites from birth to one year in a cohort of indigenous calves in western Kenya. Parasitology 2014; 141:1289-98. [PMID: 24838078 PMCID: PMC4113304 DOI: 10.1017/s003118201400050x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Tick-borne diseases are a major impediment to improved productivity of livestock in sub-Saharan Africa. Improved control of these diseases would be assisted by detailed epidemiological data. Here we used longitudinal, serological data to determine the patterns of exposure to Theileria parva, Theileria mutans, Babesia bigemina and Anaplasma marginale from 548 indigenous calves in western Kenya. The percentage of calves seropositive for the first three parasites declined from initial high levels due to maternal antibody until week 16, after which the percentage increased until the end of the study. In contrast, the percentage of calves seropositive for T. mutans increased from week 6 and reached a maximal level at week 16. Overall 423 (77%) calves seroconverted to T. parva, 451 (82%) to T. mutans, 195 (36%) to B. bigemina and 275 (50%) to A. marginale. Theileria parva antibody levels were sustained following infection, in contrast to those of the other three haemoparasites. Three times as many calves seroconverted to T. mutans before seroconverting to T. parva. No T. parva antibody response was detected in 25 calves that died of T. parva infection, suggesting that most deaths due to T. parva are the result of acute disease from primary exposure.
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VAN WYK ILANACONRADIE, GODDARD AMELIA, DE C. BRONSVOORT BMARK, COETZER JACOBUSA, HANDEL IANG, HANOTTE OLIVIER, JENNINGS AMY, LESOSKY MAIA, KIARA HENRY, THUMBI SAMM, TOYE PHIL, WOOLHOUSE MARKW, PENZHORN BANIEL. The impact of co-infections on the haematological profile of East African Short-horn Zebu calves. Parasitology 2014; 141:374-88. [PMID: 24553080 PMCID: PMC4021814 DOI: 10.1017/s0031182013001625] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Revised: 08/07/2013] [Accepted: 08/15/2013] [Indexed: 11/06/2022]
Abstract
The cumulative effect of co-infections between pathogen pairs on the haematological response of East African Short-horn Zebu calves is described. Using a longitudinal study design a stratified clustered random sample of newborn calves were recruited into the Infectious Diseases of East African Livestock (IDEAL) study and monitored at 5-weekly intervals until 51 weeks of age. At each visit samples were collected and analysed to determine the infection status of each calf as well as their haematological response. The haematological parameters investigated included packed cell volume (PCV), white blood cell count (WBC) and platelet count (Plt). The pathogens of interest included tick-borne protozoa and rickettsias, trypanosomes and intestinal parasites. Generalized additive mixed-effect models were used to model the infectious status of pathogens against each haematological parameter, including significant interactions between pathogens. These models were further used to predict the cumulative effect of co-infecting pathogen pairs on each haematological parameter. The most significant decrease in PCV was found with co-infections of trypanosomes and strongyles. Strongyle infections also resulted in a significant decrease in WBC at a high infectious load. Trypanosomes were the major cause of thrombocytopenia. Platelet counts were also affected by interactions between tick-borne pathogens. Interactions between concomitant pathogens were found to complicate the prognosis and clinical presentation of infected calves and should be taken into consideration in any study that investigates disease under field conditions.
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Affiliation(s)
- ILANA CONRADIE VAN WYK
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private bag X04, Onderstepoort, 0110, South Africa
| | - AMELIA GODDARD
- Clinical Pathology, Department Companion Animal Medicine, Faculty of Veterinary Science, University of Pretoria, Private bag X04, Onderstepoort, 0110, South Africa
| | | | - JACOBUS A. W. COETZER
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private bag X04, Onderstepoort, 0110, South Africa
| | - IAN G. HANDEL
- The Roslin Institute at the R (D) SVS, University of Edinburgh, Easter Bush, EH25 9RG, UK
| | - OLIVIER HANOTTE
- School of Biology, University of Nottingham, Nottingham NG7 2RD, UK
| | - AMY JENNINGS
- The Roslin Institute at the R (D) SVS, University of Edinburgh, Easter Bush, EH25 9RG, UK
| | - MAIA LESOSKY
- Department of Production Animal Health, Faculty of Veterinary Science, University of Pretoria, Private bag X04, Onderstepoort, 0110, South Africa
- Department of Medicine, University of Cape Town, 1000, South Africa
| | - HENRY KIARA
- International Livestock Research Institute, P.O. Box 30709-00100, Nairobi, Kenya
| | - SAM M. THUMBI
- Centre for Immunology, Infection and Evolution, University of Edinburgh, EH9 3JT, UK
| | - PHIL TOYE
- International Livestock Research Institute, P.O. Box 30709-00100, Nairobi, Kenya
| | - MARK W. WOOLHOUSE
- Centre for Immunology, Infection and Evolution, University of Edinburgh, EH9 3JT, UK
| | - BANIE L. PENZHORN
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private bag X04, Onderstepoort, 0110, South Africa
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Role of the polymorphic immunodominant molecule in entry of Theileria parva sporozoites into bovine lymphocytes. Infect Immun 2014; 82:1786-92. [PMID: 24549329 DOI: 10.1128/iai.01029-13] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Theileria parva is a tick-transmitted apicomplexan parasite that infects cattle and African buffalo. In cattle, it causes a fatal lymphoproliferative disease called East Coast fever. The polymorphic immunodominant molecule (PIM) is expressed by two stages of the parasite: the sporozoite, which is inoculated by the tick to infect mammalian lymphocytes, and the schizont, the established intralymphocytic stage. Here, we demonstrate that monoclonal antibodies (MAb) to PIM can reduce the ability of sporozoites to infect bovine lymphocytes in vitro. This reduction appears to be due to blocking of sporozoite attachment by binding of the MAb to several regions of PIM. Interestingly, one MAb, which recognizes an epitope in the central variable region of PIM, did not inhibit sporozoite infectivity. We also demonstrate that PIM antigen, as a recombinant molecule, can also reduce sporozoite infectivity in vitro by blocking both attachment and internalization of sporozoites. Electron microscopic studies showed that PIM is present in microspheres below the sporozoite surface and is transported to the parasite surface soon after contact with bovine lymphocytes. The results suggest that at least two sporozoite molecules, PIM and the previously described p67, are involved in the entry of T. parva into mammalian lymphocytes.
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Toye P, Handel I, Gray J, Kiara H, Thumbi S, Jennings A, van Wyk IC, Ndila M, Hanotte O, Coetzer K, Woolhouse M, Bronsvoort M. Maternal antibody uptake, duration and influence on survival and growth rate in a cohort of indigenous calves in a smallholder farming system in western Kenya. Vet Immunol Immunopathol 2013; 155:129-34. [PMID: 23838470 PMCID: PMC3740236 DOI: 10.1016/j.vetimm.2013.06.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 05/31/2013] [Accepted: 06/03/2013] [Indexed: 11/07/2022]
Abstract
The passive transfer of antibodies from dams to offspring via colostrum is believed to play an important role in protecting neonatal mammals from infectious disease. The study presented here investigates the uptake of colostrum by 548 calves in western Kenya maintained under smallholder farming, an important agricultural system in eastern Africa. Serum samples collected from the calves and dams at recruitment (within the first week of life) were analysed for the presence of antibodies to four tick-borne haemoparasites: Anaplasma marginale, Babesia bigemina, Theileria mutans and Theileria parva. The analysis showed that at least 89.33% of dams were seropositive for at least one of the parasites, and that 93.08% of calves for which unequivocal results were available showed evidence of having received colostrum. The maternal antibody was detected up until 21 weeks of age in the calves. Surprisingly, there was no discernible difference in mortality or growth rate between calves that had taken colostrum and those that had not. The results are also important for interpretation of serosurveys of young calves following natural infection or vaccination.
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Affiliation(s)
- Philip Toye
- The International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya
| | - Ian Handel
- The Roslin Institute, University of Edinburgh, Easter Bush EH25 9RG, UK
| | - Julia Gray
- College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
| | - Henry Kiara
- The International Livestock Research Institute (ILRI), P.O. Box 30709, Nairobi 00100, Kenya
| | - Samuel Thumbi
- Centre for Immunology, Infection & Evolution, University of Edinburgh, EH9 3JT, UK
| | - Amy Jennings
- Centre for Immunology, Infection & Evolution, University of Edinburgh, EH9 3JT, UK
| | - Ilana Conradie van Wyk
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - Mary Ndila
- School of Biology, University of Nottingham, Nottingham NG7 2RD, UK
| | - Olivier Hanotte
- School of Biology, University of Nottingham, Nottingham NG7 2RD, UK
| | - Koos Coetzer
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - Mark Woolhouse
- Centre for Immunology, Infection & Evolution, University of Edinburgh, EH9 3JT, UK
| | - Mark Bronsvoort
- The Roslin Institute, University of Edinburgh, Easter Bush EH25 9RG, UK
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Kivaria FM, Kapaga AM, Mbassa GK, Mtui PF, Wani RJ. Epidemiological perspectives of ticks and tick-borne diseases in South Sudan: cross-sectional survey results. ACTA ACUST UNITED AC 2012; 79:E1-E10. [PMID: 23327317 DOI: 10.4102/ojvr.v79i1.400] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Revised: 04/02/2012] [Accepted: 05/11/2012] [Indexed: 11/01/2022]
Abstract
A cross-sectional study was conducted between September and October 2010 in five states of South Sudan that were selected on the basis of the perceived risk of tick-borne diseases. The purpose was to investigate epidemiological parameters of tick-borne diseases in South Sudan and their uses in future control strategies. A total of 805 calves were assessed by clinical, microscopic and serological examination and tick counts. The indirect Enzyme-Linked Immuno-Sorbent Assay (ELISA) was used to detect antibodies to Theileria parva, Theileria mutans, Anaplasma marginale and Babesian bigemina. Sero-conversion risks for T. parva and T. mutans were 27.3% and 31.3% respectively, whilst the risk was 57.6% and 52.8% for A. marginale and B. bigemina, respectively. Major tick species identified include Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus microplus, Amblyomma variegatum, and Rhipicephalus evertsi. There was great variation (P ≤ 0.001) in the number of all these ticks, both between herds in a state and between calves in an individual herd. The low and intermediate sero-conversion risks observed in the study states suggest that immunisation against East Coast fever (ECF) is justified. Fortunately, three major genotypes that were identified by applying Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCRRFLP) analysis on the p104 to the blood samples and T. parva Muguga, matched very well with T. parva Kiambu 5 and T. parva Muguga; therefore the Muguga cocktail can be used for the immunisation of cattle in South Sudan. However, prospective studies are required to develop optimal control measures for tick-borne diseases under different ecological and husbandry practices in South Sudan.
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Affiliation(s)
- Fredrick M Kivaria
- National Epidemiology Section, Ministry of Livestock and Fisheries Development.
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Martins SB, Di Giulio G, Lynen G, Peters A, Rushton J. Assessing the impact of East Coast Fever immunisation by the infection and treatment method in Tanzanian pastoralist systems. Prev Vet Med 2010; 97:175-82. [PMID: 20974501 DOI: 10.1016/j.prevetmed.2010.09.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 09/21/2010] [Accepted: 09/22/2010] [Indexed: 10/18/2022]
Abstract
A field trial was carried out in a Maasai homestead to assess the impact of East Coast Fever (ECF) immunisation by the infection and treatment method (ITM) with the Muguga Cocktail on the occurrence of this disease in Tanzanian pastoralist systems. These data were further used in partial budgeting and decision analysis to evaluate and compare the value of the control strategy. Overall, ITM was shown to be a cost-effective control option. While one ECF case was registered in the immunised group, 24 cases occurred amongst non-immunised calves. A significant negative association between immunisation and ECF cases occurrence was observed (p≤0.001). ECF mortality rate was also lower in the immunised group. However, as anti-theilerial treatment was given to all diseased calves, no significant negative association between immunisation and ECF mortality was found. Both groups showed an overall similar immunological pattern with high and increasing percentages of seropositive calves throughout the study. This, combined with the temporal distribution of cases in the non-immunised group, suggested the establishment of endemic stability. Furthermore, the economic analysis showed that ITM generated a profit estimated to be 7250 TZS (1 USD=1300 TZS) per vaccinated calf, and demonstrated that it was a better control measure than natural infection and subsequent treatment.
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Affiliation(s)
- S Babo Martins
- The Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA, UK.
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13
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Estimating seroprevalence and variation to four tick-borne infections and determination of associated risk factors in cattle under traditional mixed farming system in Mbeere District, Kenya. Prev Vet Med 2010; 95:208-23. [DOI: 10.1016/j.prevetmed.2010.03.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/10/2010] [Accepted: 03/26/2010] [Indexed: 11/20/2022]
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Sequence heterogeneity in the equi merozoite antigen gene (ema-1) of Theileria equi and development of an ema-1-specific TaqMan MGB assay for the detection of T. equi. Vet Parasitol 2010; 172:33-45. [PMID: 20493635 DOI: 10.1016/j.vetpar.2010.04.025] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 04/08/2010] [Accepted: 04/19/2010] [Indexed: 11/22/2022]
Abstract
Although a quantitative real-time PCR assay (qPCR) assay for the detection of Theileria equi has been developed and evaluated, it is possible that additional, as yet undetected 18S rRNA gene sequence variants may exist. A qPCR assay targeting a different gene, used in conjunction with the T. equi 18S rRNA qPCR assay, could assist in the detection of all T. equi genotypes in field samples. A T. equi ema-1-specific qPCR (Ueti et al., 2003) was tested on 107 South African field samples, 90 of which tested positive for T. equi antibody using the immuno-fluorescent antibody test (IFAT). The qPCR assay performed poorly, as T. equi was detected in only 67 of the 90 IFAT-positive field samples at quantification cycle (C(q)) values ranging from 27 to 39.95. Furthermore, a high C(q) value of 36.18 was obtained from DNA extracted from a South African in vitro-cultured T. equi WL isolate [1.38% parasitized erythrocytes (PE)] when a low C(q) value (indicative of a high T. equi DNA concentration) was expected. Approximately 600 bp of the ema-1 gene from 38 South African samples were sequenced and BLASTN analysis confirmed all sequences to be merozoite surface protein genes, with an identity of 87.1-100% to previously published T. equi ema-1 gene sequences. Alignment of the sequences revealed extensive sequence variations in the target regions of the primers and probes (Ueti et al., 2003), explaining the poor performance of the qPCR assay. Based on these observations, we developed a new TaqMan minor-groove binder (MGB) probe-based qPCR assay, targeting a more conserved region of the ema-1 gene. This assay was shown to be efficient and specific, and the detection limit, defined as the concentration at which 95% of T. equi-positive samples are detected, was determined to be 1.4 x 10(-4)% PE. The two ema-1 assays were compared by testing 41 South African field samples in parallel. The results suggested that the new assay was more sensitive than the original assay, as T. equi was detected in more samples and at lower C(q) values when the new assay was used. Phylogenetic analyses of the 18S rRNA gene sequences and ema-1 amino acid sequences from the same samples showed inconsistencies between the clades, indicating that the T. equi 18S rRNA genetic groups previously identified in South Africa may not represent distinct T. equi lineages. It is possible that the different T. equi ema-1 genotypes could be related to antigenic variability and pathogenicity and may be associated with clinical differences in equine piroplasmosis cases, but this remains to be elucidated.
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Swai ES, Karimuribo ED, Kambarage DM, Moshy WE. A longitudinal study on morbidity and mortality in youngstock smallholder dairy cattle with special reference to tick borne infections in Tanga region, Tanzania. Vet Parasitol 2008; 160:34-42. [PMID: 19091478 DOI: 10.1016/j.vetpar.2008.10.101] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 10/17/2008] [Accepted: 10/20/2008] [Indexed: 10/21/2022]
Abstract
The incidence and potential determinants of tick borne diseases (TBDs) were estimated in a longitudinal study that was conducted in cohorts of youngstock animals of less than 3 years kept in smallholder dairy farms in Tanga region, Tanzania. A combination of serological tests, blood and lymph node smears were used as diagnostic tests for TBDs during the study. A total number of 549 youngstock were followed for a total of 532.2 animal years from August 1999 to July 2001. Overall morbidity and mortality rates (due to all causes) were 8.26 and 12.0 per 100 animals year at risk, respectively. Of the total deaths, 56% were attributed to TBDs (37.5%-East Coast fever (ECF) and 18%-anaplasmosis). Specific morbidity and mortality rates for ECF were estimated to be 3.57 and 4.51 per 100 animals year risk, respectively, and for anaplasmosis 2.21 and 2.25 per 100 animals year risk, respectively. Analysis of survival times to death indicated that calves < 6 months of age and those out on pasture had higher death rates than older calves and those kept under zero-grazing systems (relative risk [RR] 3.80, P = 0.001 for pasture-grazed calves). There was no mortality or morbidity arising specifically from cowdriosis (heartwater) or babesiosis during the whole period of monitoring. The study revealed that most farms were applying under strength acaricide and using acaricides at irregular intervals. It is concluded that TBDs namely ECF and anaplasmosis are important diseases in this farming system and reducing morbidity and mortality in smallholder dairy farms in Tanga region is an achievable goal. Both farmers and extension services should target at risk calves with the provision of both strict tick control and optimal husbandry management practices.
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Affiliation(s)
- Emmanuel S Swai
- Veterinary Investigation Centre (VIC), Box 1068, Arusha, Tanzania.
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Salih DA, Hassan SM, Julla II, Kyule MN, Zessin KH, El Hussein AM. Distribution and Application of ELISA for the Seroprevalence of Tick-Borne Diseases in Central Equatoria State, Sudan. Transbound Emerg Dis 2008; 55:257-62. [DOI: 10.1111/j.1865-1682.2008.01032.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Swai ES, Karimuribo ED, Kambarage DM, Moshy WE, Mbise AN. A comparison of seroprevalence and risk factors for Theileria parva and T. mutans in smallholder dairy cattle in the Tanga and Iringa regions of Tanzania. Vet J 2007; 174:390-6. [PMID: 17015024 DOI: 10.1016/j.tvjl.2006.08.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2006] [Revised: 08/10/2006] [Accepted: 08/11/2006] [Indexed: 11/19/2022]
Abstract
A cross sectional serological survey was carried out in two geographical small-scale dairying areas of Tanzania to determine the distribution and prevalence and to quantify risk factors for Theileria parva and T. mutans during the period January to April 1999. The prevalence of serum antibodies to these two Theileria parasites was determined using an indirect enzyme-linked immunosorbent assay (ELISA) technique. The results suggest that the parasites are widely distributed through out the two study sites and seroprevalence of 23% and 48% for T. parva were obtained for Tanga and Iringa regions, respectively. Seroprevalence of T. mutans ranged from 17% in the Tanga region to 40% in the Iringa region. Farm and animal data were collected and analysed by multiple logistic regression models to explore the risk factors associated with seroprevalence to T. parva and T. mutans pathogens. In both regions, seroprevalence for the two Theileria spp. pathogens increased significantly with age. Pasture grazed animals were more likely to be seropositive than those that were zero-grazed. Among individual animal characteristics, seropositivity was higher in cash-bought and charity gifted animals compared to cattle obtained using a formal credit agreement. Further studies on the relative role of risk factors for theileriosis found in this study may assist in the development of an effective control package.
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Affiliation(s)
- Emmanuel S Swai
- Veterinary Investigation Centre (VIC), Box 1068, Arusha, Tanzania.
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18
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Swai ES, French NP, Karimuribo ED, Fitzpatrick JL, Bryant MJ, Brown PE, Ogden NH. Spatial and management factors associated with exposure of smallholder dairy cattle in Tanzania to tick-borne pathogens. Int J Parasitol 2006; 35:1085-96. [PMID: 16023121 DOI: 10.1016/j.ijpara.2005.04.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2005] [Revised: 04/20/2005] [Accepted: 04/21/2005] [Indexed: 10/25/2022]
Abstract
A cross-sectional study of serum antibody responses of cattle to tick-borne pathogens (Theileria parva, Theileria mutans,Anaplasma marginale, Babesia bigemina and Babesia bovis) was conducted on smallholder dairy farms in Tanga and Iringa Regions of Tanzania. Seroprevalence was highest for T. parva (48% in Iringa and 23% in Tanga) and B. bigemina (43% in Iringa and 27% in Tanga) and lowest for B. bovis (12% in Iringa and 6% in Tanga). We use spatial and non-spatial models, fitted using classical and Bayesian methods, to explore risk factors associated with seroprevalence. These include both fixed effects (age, grazing history and breeding status) and random effects (farm and local spatial effects). In both regions, seroprevalence for all tick-borne pathogens increased significantly with age. Animals pasture grazed in the 3 months prior to the start of the sampling period were significantly more likely to be seropositive for Theileria spp. and Babesia spp. Pasture grazed animals were more likely to be seropositive than zero-grazed animals for A. marginale, but the relationship was weaker than that observed for the other four pathogens. This study did not detect any significant differences in seroprevalence associated with other management-related variables, including the method or frequency of acaricide application. After adjusting for age, there was weak evidence of localised (<5 km) spatial correlation in exposure to some of the tick borne diseases. However, this was small compared with the 'farm-effect', suggesting that risk factors specific to the farm were more important than those common to the local neighbourhood. Many animals were seropositive for more than one pathogen and the correlation between exposure to the different pathogens remained after adjusting for the identified risk factors. Identifying the determinants of exposure to multiple tick-borne pathogens and characterizing local variation in risk will assist in the development of more effective control strategies for smallholder dairy farms.
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Affiliation(s)
- E S Swai
- Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania
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Swai ES, Karimuribo ED, Ogden NH, French NP, Fitzpatrick JL, Bryant MJ, Kambarage DM. Seroprevalence Estimation and Risk Factors for A. marginale on Smallholder Dairy Farms in Tanzania. Trop Anim Health Prod 2005; 37:599-610. [PMID: 16619876 DOI: 10.1007/s11250-005-4307-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
A cross-sectional serological survey of A. marginale was conducted on 200 randomly selected smallholder farms in each of the Tanga and Iringa Regions of Tanzania between January and April 1999. Sera, from dairy cattle of all ages, sexes and breeds were tested for antibodies against A. marginale using an indirect enzyme-linked immunosorbent assay. Antibodies to A. marginale were present in cattle throughout the study areas and the overall prevalence was 20% for Tanga and 37% for Iringa. The forces of infection based on the age seroprevalence profile were estimated at 8 for Tanga and 15 for Iringa per 100 cattle years-risk, respectively. In both regions, seroprevalence increased with age (beta = 0.01 and 0.017 per year of age, p < 0.005, in Tanga and Iringa, respectively). Older animals in Iringa were significantly and negatively associated with decreased seropositivity (beta = -0.002, p = 0.0029). Further results of logistic regression models reveal that geographic location of animals in Tanga was associated with seropositivity (odds ratio (OR) = 2.94, p = 0.005, for Tanga Rural and OR = 2.38, p = 0.066, for Muheza). Animals acquired as a gift in Iringa had higher odds for seropositivity than brought-in cattle (OR = 2.44, p = 0.005). Our study has identified and quantified some key risk factors that can guide planners devising disease control strategies.
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Affiliation(s)
- E S Swai
- Veterinary Investigation Centre, Arusha
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20
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Swai ES, French NP, Beauchamp G, Fitzpatrick JL, Bryant MJ, Kambarage D, Ogden NH. A longitudinal study of sero-conversion to tick-borne pathogens in smallholder dairy youngstock in Tanzania. Vet Parasitol 2005; 131:129-37. [PMID: 15936149 DOI: 10.1016/j.vetpar.2005.04.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Revised: 04/25/2005] [Accepted: 04/27/2005] [Indexed: 11/16/2022]
Abstract
A longitudinal study of sero-conversion of youngstock to the tick-borne pathogens Theileria parva, T. mutans, Anaplasma marginale, Babesia bigemina and B. bovis was conducted over two years on smallholder dairy farms in Tanga region, Tanzania. There was evidence of maternal antibodies to all tick-borne pathogens in animals less than 18 weeks of age. Seroprevalence increased as expected with age in animals older than this but seroprevalence profiles underestimated the force of infection due to waning antibody levels between samplings. By the end of the 2-year study, less than 50% of study animals had seroconverted to each of the tick-borne pathogens investigated, consistent with the low levels of tick attachment observed on the study animals. Some associations between seroconversion to tick-borne pathogens, and counts of their known tick vectors on the animals, were identified as expected. However, some were not, suggesting that counts of some tick species may act as an index of rates of attachment of other vector species. Variation in acaricide treatment frequencies was not associated with variations in tick-borne pathogen seroprevalence suggesting that acaricides may be used more frequently than necessary on many farms. Most animals were zero-grazed, a management system associated with a significantly lower likelihood that animals seroconverted to any tick-borne pathogen except A. marginale. Seroprevalence varied locally with farm location (particularly for Babesia spp.) but was not well predicted by indices of ecological conditions. Our findings suggest that attempts to achieve a state of 'endemic stability' for tick-borne pathogens may be unreasonable on the smallholder dairy farms studied but reductions in the frequency of use of acaricides may be possible following prospective studies of effects on mortality and morbidity due to tick-borne pathogens.
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Affiliation(s)
- E S Swai
- Tanga Dairy Development Programme, Tanga, Tanzania
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Abstract
The classification of the benign species of Theileria of cattle is very confusing Representatives of this group of parasites appear worldwide, and are known as T. sergenti in Japan, T. buffeli in Australia and T. orientalis elsewhere. Consequently, these parasites are frequently referred to as the T. sergenti/buffeli/orientalis group. Kozo Fujisaki, Shin-ichiro Kawazu and Tsugihiko Kamio here argue that the Australian T. buffeli and British T. orientalis belong to one and the same species, and that the Japanese T. sergenti is a separate species.
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Affiliation(s)
- K Fujisaki
- Protozoology Laboratory, The First Research Division, National Institute of Animal Health, Ministry o f Agriculture, Forestry and Fisheries, Tsukubo, Ibaraki 305, Japan
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Katzer F, McKellar S, Ferguson MAJ, d'Oliveira C, Shiels BR. A role for tertiary structure in the generation of antigenic diversity and molecular association of the Tams1 polypeptide in Theileria annulata. Mol Biochem Parasitol 2002; 122:55-67. [PMID: 12076770 DOI: 10.1016/s0166-6851(02)00078-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The major merozoite-piroplasm surface antigen (mMPSA) of Theileria annulata, Tams1, is known to be antigenically diverse. The possession of variable N-linked glycosylation sites and removal of monoclonal antibody 5E1 reactivity by mild periodate treatment suggested, previously, that divergent epitopes may be conferred by secondary modification. This study has shown that monoclonal antibody 5E1 and polyspecific antisera raised against the native protein react against divergent amino acid epitopes that are dependent on a molecular conformation that is sensitive to periodate. Therefore, no experimental evidence exists to confirm the sequence prediction that Tams1 undergoes N-linked glycosylation. Data is also presented indicating that the conformation of the antigen results in presentation of divergent regions on the external surface of the molecule, while conserved regions are more likely to be internal and hidden. In addition, non-reducing SDS-PAGE analysis demonstrated that Tams1 can undergo molecular association to form homo-dimers, trimers and multimers. The potential influence of tertiary structure and inter-molecular association on Tams1 diversity and function is discussed.
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Affiliation(s)
- Frank Katzer
- Department of Veterinary Parasitology, Faculty of Veterinary Medicine, University of Glasgow, Glasgow, UK
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Govaerts M, Verhaert P, Jongejan F, Goddeeris BM. Characterisation of the 33kDa piroplasm surface antigen of Theileria orientalis/sergenti/buffeli isolates from West Java, Indonesia. Vet Parasitol 2002; 104:103-17. [PMID: 11809330 DOI: 10.1016/s0304-4017(01)00621-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The immunodominant 33/35kDa antigen of a Theileria isolate from West Java, Indonesia, was characterised and immuno-affinity purified by use of a monoclonal antibody, KUL-a4, and was shown to be representative of the T. orientalis/sergenti/buffeli group. The aminoterminal sequence of the purified 35kDa peptide (20 residues) was determined by automated Edman degradation and found to correspond to the predicted amino acid sequence of a prospective p33 gene previously sequenced from the same isolate. The cleavage site of a putative signal peptide was identified and conforms the (-3, -1) rule for signal peptidases. The existence of dimeric and trimeric forms of the p33/35 antigen is hypothesised from Western blot profiles. KUL-a4 appeared specific for the T. orientalis/sergenti/buffeli group. It did not recognise in indirect fluorescence antibody test (IFAT), intraerythrocytic bodies of Anaplasma marginale or piroplasms and schizonts of T. mutans, T. parva and T. annulata, whereas cattle antisera raised to these species showed cross-reactivity in IFAT. It however, appeared weakly cross-reactive in Western blot and ELISA, with the 34kDa piroplasm antigen of one T. annulata (Gharb) isolate. The present study indicates that the isolated antigen belongs to the p33/34 antigen family described within the T. sergenti/orientalis/buffeli group, and documents the group-specificity of one of its epitopes.
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Affiliation(s)
- Marc Govaerts
- Laboratory of Physiology and Immunology of Domestic Animals, Katholieke Universiteit Leuven, Kasteelpark Arenburg 30, B-3001 Heverlee, Leuven, Belgium
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Carrique Mas JJ, Widdowson MA, Cuéllar AM, Ribera H, Walker AR. Risk of babesiosis and anaplasmosis in different ecological zones of Santa Cruz Department, Bolivia. Vet Parasitol 2000; 93:29-38. [PMID: 11027858 DOI: 10.1016/s0304-4017(00)00328-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A cross-sectional study was done of seroprevalence of Babesia bigemina, B.bovis, and Anaplasma marginale in cattle from eastern Bolivia, to characterise the risk of tick-borne disease in three ecological zones. Nineteen farms were sampled in the subtropical humid zone, 13 in the dry subtropical zone and nine in the lower western valleys of the Andean massif. The enzyme-linked immunosorbent assay was used. All three pathogens were widespread. For B. bovis, seroprevalences were high (75-78%) in the two subtropical zones which thus had low risk of disease from this infection; but the western valleys were endemically unstable with higher risk. For B. bigemina, seroprevalences were lower (24-57%) in the two subtropical zones and thus these areas were endemically unstable for disease from this infection. However, the seroprevalence of B. bigemina in the western valleys was too low (13%) for risk of disease in susceptible cattle to be considered high. For A. marginale, the seroprevalences in the two subtropical zones were low (19-32%) and very low (6%) in the western valleys suggesting all these zones were endemically unstable for anaplasmosis. Data for individual farms were analysed for risk of both forms of babesiosis; this showed low risk of disease in the subtropical humid zone, higher risk in the dry subtropical zone and variable risk in the western valleys.
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Affiliation(s)
- J J Carrique Mas
- Laboratorio de Investigación y Diagnóstico Veterinario, Avenida Ejercito Nacional, 153, Santa Cruz de la Sierra, Bolivia
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Knight PA, Williamson SW, Brown CG, Bell-Sakyi L, Kirvar E, Kinnaird J, Hussain K, Hall R, Boulter N, Tait A. Identification of a Theileria annulata antigen expressed in multiple stages of the parasite life cycle. Exp Parasitol 1998; 90:110-21. [PMID: 9709037 DOI: 10.1006/expr.1998.4303] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In order to identify sporozoite surface molecules which may be involved in invasion and could act as potential vaccine candidates, a number of Mabs were raised in mice against T. annulata sporozoites. These were assayed for their ability to block sporozoite invasion of bovine peripheral blood mononuclear (PBM) cells in vitro. One of these, Mab 4B11, was found to neutralize sporozoite invasion to a high degree and to recognize a group of sporozoite antigens on Western blots. A T. annulata lambdagt11 genomic expression library was screened with Mab 4B11 and a positive clone containing a 900-bp insert (KP8) analysed further. Data from Southern and Northern blotting indicated that the gene containing the KP8 sequence, termed sporozoite and macroschizont gene 2 (spm2), was expressed both in T. annulata sporozoites and in later parasite life-cycle stages, macroschizont-infected leucocytes and piroplasms. The KP8 sequence was expressed in E. coli as a fusion protein with glutathione-S-transferase (GST) using the vector pGEX1lambdaT. Bovine antiserum raised against GST-KP8 recognised a single high molecular weight molecule on Western blots corresponding to one of the antigens recognised by Mab 4B11, expressed in sporozoites, macroschizont-infected leucocytes, and piroplasms. While our evidence suggests that the spm2 molecule alone is not responsible for sporozoite neutralization, it is a multistage antigen likely to function both in T. annulata sporozoites and in subsequent parasite life-cycle stages.
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Affiliation(s)
- P A Knight
- Centre for Tropical Veterinary Medicine, Veterinary Field Station, University of Edinburgh, Easter Bush, Roslin, Midlothian, Edinburgh, EH25 9RG, UK
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Binta MG, Losho T, Allsopp BA, Mushi EZ. Isolation of Theileria taurotragi and Theileria mutans from cattle in Botswana. Vet Parasitol 1998; 77:83-91. [PMID: 9746278 DOI: 10.1016/s0304-4017(98)00100-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Two Theileria species demonstrated in peripheral Giemsa-stained blood smears of sick cattle from various parts of Botswana were subsequently identified as Theileria mutans and T. taurotragi using DNA hybridization and the polymerase chain reaction. Initial screening for Theileria species was done using microscopy, the indirect fluorescent antibody technique and the micro Elisa test. The syndrome was characteristically that of high morbidity but low mortality and vague malaise. A low parasitaemia of pleomorphic intra-erythrocytic piroplasms and the absence of schizont stages in circulating lymphocytes and lymph node aspirates were evident. Dual infections were common and often complicated by intercurrent disease conditions.
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Affiliation(s)
- M G Binta
- National Veterinary Laboratory, Gaborone, Botswana
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28
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Gentschev I, Glaser I, Goebel W, McKeever DJ, Musoke A, Heussler VT. Delivery of the p67 sporozoite antigen of Theileria parva by using recombinant Salmonella dublin: secretion of the product enhances specific antibody responses in cattle. Infect Immun 1998; 66:2060-4. [PMID: 9573089 PMCID: PMC108163 DOI: 10.1128/iai.66.5.2060-2064.1998] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The p67 sporozoite antigen of Theileria parva has been fused to the C-terminal secretion signal of Escherichia coli hemolysin and expressed in secreted form by attenuated Salmonella dublin aroA strain SL5631. The recombinant p67 antigen was detected in the supernatant of transformed bacterial cultures. Immunization trials in cattle revealed that SL5631 secreting the antigen provoked a 10-fold-higher antibody response to p67 than recombinant SL5631 expressing but not secreting p67. Immunized calves were challenged with a 80% lethal dose of T. parva sporozoites and monitored for the development of infection. Two of three calves immunized intramuscularly with the p67-secreting SL5631 strain were found to be protected, whereas only one of three animals immunized with the nonsecreting p67-expressing SL5631 strain was protected. This is the first demonstration that complete eukaryotic antigens fused to the C-terminal portion of E. coli hemolysin can be exported from attenuated Salmonella strains and that such exported antigens can protect cattle against subsequent parasite challenge.
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Affiliation(s)
- I Gentschev
- Lehrstuhl für Mikrobiologie, Theodor-Boveri-Institut für Biowissenschaften, Würzburg, Germany
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29
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Heussler VT, Taracha EL, Musoke A, Duchateau L, McKeever DJ. Immunisation with live attenuated Salmonella dublin expressing a sporozoite protein confers partial protection against Theileria parva. Vaccine 1998; 16:834-41. [PMID: 9627941 DOI: 10.1016/s0264-410x(97)00263-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cattle immunised with a recombinant form of p67, the major surface antigen of Theileria parva sporozoites, have been shown to be protected against parasite challenge. In an attempt to simplify the immunisation procedure live attenuated Salmonella strains expressing p67 have been constructed and used to induce anti-p67 immune responses in cattle. All animals immunised with these strains developed strong antibody responses to p67. Specific T cell responses could be detected in the majority of immunised cattle. Challenge with T. parva sporozoites revealed a significant level of protection in immunised calves compared to naive control animals or animals inoculated with non-recombinant attenuated Salmonella.
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Affiliation(s)
- V T Heussler
- Institute of Animal Pathology, Berne, Switzerland
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30
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Passos LM, Bell-Sakyi L, Brown CG. Immunochemical characterization of in vitro culture-derived antigens of Babesia bovis and Babesia bigemina. Vet Parasitol 1998; 76:239-49. [PMID: 9650861 DOI: 10.1016/s0304-4017(98)00095-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Cross-reactivity between Babesia bovis and B. bigemina becomes a problem in discrimination of the two infections in endemic areas where the two species usually occur in association. With the aim of identifying candidate proteins for use as specific diagnostic tools, culture-derived components of three geographically different stocks of B. bovis (Lismore, Kwanyanga and Mexico) and one of B. bigemina (Mexico) were analyzed by immunoprecipitation using acrylamide gel electrophoresis. The approach taken was based on the analysis of 35S-methionine-labelled parasite antigens released into culture supernatant. A variety of serum samples were tested, including a panel of calf sera experimentally produced against the different stocks of Babesia, serum samples from cattle naturally infected in the field in Brazil, and a panel of anti-B. bovis monoclonal antibodies, previously characterized by the indirect fluorescent antibody test, ELISA and Western immuno-blotting. Approximately 28 and 23 bands (with molecular weights ranging from 200 to 14 kDa) were detected in total protein profiles of B. bovis and B. bigemina culture supernatants, respectively, whereas no bands were seen in the uninfected red blood cell culture supernatant (negative control). The immunoprecipitation analysis showed antigenic diversity amongst the stocks of B. bovis and resulted in identification of at least five B. bovis specific antigens common to the three stocks (molecular weights of 80, 72, 58, 38 and 24 kDa) and four B. bigemina specific antigens (molecular weights of 240, 112, 50 and 29 kDa).
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Affiliation(s)
- L M Passos
- Escola de Veterinária, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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31
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Gitau GK, Perry BD, Katende JM, McDermott JJ, Morzaria SP, Young AS. The prevalence of serum antibodies to tick-borne infections in cattle in smallholder dairy farms in Murang'a District, Kenya; a cross-sectional study. Prev Vet Med 1997; 30:95-107. [PMID: 9234414 DOI: 10.1016/s0167-5877(96)01100-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The most important tick-borne disease of cattle in eastern, central and southern Africa is East Coast fever (ECF) caused by Theileria parva and transmitted by the tick Rhipicephalus appendiculatus. Other less-important tick-borne diseases in cattle are benign theileriosis caused by Theileria mutans, babesiosis caused by Babesia bigemina, anaplasmosis caused by Anaplasma marginale and cowdriosis caused by Cowdria ruminatum. In Murang's District, Central Province of Kenya, five agroecological zones (AEZs) are defined according to climate, altitude and agricultural activities. A cross-sectional serological study was conducted on 750 smallholder dairy farms in Murang's District, selected in a stratified random sampling method. The farms had a total of 362 calves. One hundred and fifty farms were studied from three administrative sublocations in each of the five AEZs. Prevalence of serum antibodies to three tick-borne parasites, that is T. parva, T. mutans and B. bigemina, were determined using the enzyme-linked immunosorbent assay (ELISA) technique. Antibody prevalence values differed across the AEZs. The ranges of means for the prevalences were: T. parva (18-72%), T. mutans (1.5-28%) and B. bigemina (12-49%). The above results serve as indicators of the possible existence of endemic stability in some AEZs for some parasites.
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Affiliation(s)
- G K Gitau
- Dept of Clinical Studies, University of Nairobi, Kenya
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32
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Young AS, Waladde SM, Morzaria SP. Artificial feeding systems for ixodid ticks as a tool for study of pathogen transmission. Ann N Y Acad Sci 1996; 791:211-8. [PMID: 8784502 DOI: 10.1111/j.1749-6632.1996.tb53527.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- A S Young
- International Livestock Research Institute (ILRI), Nairobi, Kenya
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33
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Abstract
Infection of horses with the hemoprotozoan Babesia equi has been reported in southern Florida, US Virgin Islands, part of Asia, Russia, India, the Middle East, Europe, Africa, Australia, South America, Central America, Mexico, Philippine Islands and some Caribbean islands. The restrictions placed on the international movement of infected horses has refocused attention on potential methods to control or eliminate infection. Don Knowles here discusses the primary chemotherapeutic compounds that have been used; the current knowledge concerning immune responses that potentially contribute to control of the parasite, and the development of infection of severe combined immuno-deficient foals as a model to dissect potential mechanisms of immunological control.
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Affiliation(s)
- D P Knowles
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7030, USA
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34
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Buza JJ, Logan-Henfrey L, Andrianarivo AG, Williams DJ. Rise in erythropoietin concentrations in experimental Trypanosoma congolense infection of calves. J Comp Pathol 1995; 113:343-56. [PMID: 8746957 DOI: 10.1016/s0021-9975(05)80120-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A bioassay was used to measure erythropoietin (EPO) concentrations in calves with haemorrhagic anaemia due to blood loss and in calves with anaemia due to Trypanosoma congolense infection. The bioactivity of EPO was measured in the assay by its stimulatory effect on 125I-deoxyuridine incorporation in spleen cells from phenylhydrazine-treated mice. Erythropoietin concentrations in blood-volume-depleted calves were elevated 6 h after blood loss, maximal (1225 mU/ml) at 33 h and below detection limits at 72 h. Reticulocytes (0.05 +/- 0.1%) appeared in blood by 72 h, peaked at 120 h and disappeared from the circulation by 7 days after bleeding. The packed cell volume (PCV) started increasing at 120 h and reached near pre-bleeding values by 14 days. In T. congolense-infected calves, parasites were first detected in the peripheral blood 12 days post-infection (dpi). Parasitaemia peaked (5 x 10(5) trypanosomes/ml of blood) at 15-18 dpi and, thereafter, several waves of parasitaemia were observed, but the peaks gradually diminished. Undiluted plasma from T. congolense-infected calves suppressed 125I-deoxyuridine incorporation into spleen cells from 13 dpi onwards. The suppressive effect of plasma was partly negated by five-fold dilution, which made possible the detection of increased EPO concentrations during the acute and chronic stages of the anaemia. The highest EPO peaks, reaching 2300 mU/ml in one calf, were detected during the chronic stage of the infection. At 15-39 dpi, there was a transient bone-marrow erythropoietic response characterized by an increase in mean corpuscular volume and a decrease in mean corpuscular haemoglobin concentration but with few reticulocytes (0.4%). However, from 76 dpi onwards, this response waned despite low PCV and elevated EPO concentrations. These results suggest that there is an ineffective erythroid response in the face of elevated EPO concentrations during bovine trypanosomiasis. The negative effect of plasma and serum from trypanosome-infected calves on the in-vitro bioactivity of EPO suggests the presence of inhibitory factors.
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Affiliation(s)
- J J Buza
- International Livestock Research Institute, Nairobi, Kenya, UK
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35
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Shiels BR, d'Oliveira C, McKellar S, Ben-Miled L, Kawazu S, Hide G. Selection of diversity at putative glycosylation sites in the immunodominant merozoite/piroplasm surface antigen of Theileria parasites. Mol Biochem Parasitol 1995; 72:149-62. [PMID: 8538686 DOI: 10.1016/0166-6851(95)00074-b] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The immunodominant merozoite/piroplasm surface antigen of Theileria parasites has potential as a diagnostic reagent and as a component of a sub-unit vaccine. This molecule is known to be antigenically diverse, and it is important to determine the nature and extent of this heterogeneity. In the present study nucleotide sequences, representing alleles of the gene (Tams1) encoding this molecule in Theileria annulata were compared to each other and to sequences of homologous genes in Theileria sergenti, Theileria buffeli and Theileria parva. This analysis revealed that a region of the polypeptide which contains putative N-linked glycosylation sites is particularly diverse and, in analogy to retroviral systems, may indicate selection of variable glycosylation sites or amino acid epitopes to evade the bovine immune response. This conclusion was also made from the results of a phylogenetic analysis which compared the variable region of the genes with a second region, which appeared to show no bias for diversity or functional constraint. The results indicated that the variable sequence encoding putative glycosylation sites has diverged, both within and between Theileria species, at a much faster rate than the rest of the molecule. Southern blot analysis of T. annulata populations from within a single geographical region detected six possible variant Tams1 alleles. However, a correlation between restriction-fragment-length polymorphism (RFLP) patterns detected by the Tams1-1 gene probe and geographical location could not be made. In addition, although a high prevalence of one particular RFLP was found, this is unlikely to be the result of a clonal population structure, as we present evidence for significant parasite genotypic variability within a single endemic region.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antigenic Variation/genetics
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Antigens, Protozoan/metabolism
- Base Sequence
- Cattle
- DNA, Protozoan/genetics
- Evolution, Molecular
- Genes, Protozoan
- Glycosylation
- Immunodominant Epitopes/genetics
- Immunodominant Epitopes/immunology
- Immunodominant Epitopes/metabolism
- Molecular Sequence Data
- Phylogeny
- Polymorphism, Restriction Fragment Length
- Protein Processing, Post-Translational
- Recombination, Genetic
- Selection, Genetic
- Sequence Alignment
- Sequence Homology, Amino Acid
- Species Specificity
- Theileria/genetics
- Theileria/immunology
- Theileria/metabolism
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Affiliation(s)
- B R Shiels
- Department of Veterinary Parasitology, University of Glasgow, UK
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36
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Nene V, Inumaru S, McKeever D, Morzaria S, Shaw M, Musoke A. Characterization of an insect cell-derived Theileria parva sporozoite vaccine antigen and immunogenicity in cattle. Infect Immun 1995; 63:503-8. [PMID: 7822014 PMCID: PMC173023 DOI: 10.1128/iai.63.2.503-508.1995] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Previous data showed that six out of a group of nine cattle inoculated with NS1-p67, a recombinant form of a 67-kDa Theileria parva sporozoite surface protein, were immune to East Coast fever. This bacterially expressed antigen encoded all 709 amino acid residues of p67 fused to the C-terminal end of 87 residues derived from NS1, a structural protein of influenza virus, and a linker DNA sequence. NS1-p67 lacked reactivity with TpM 12, a monoclonal antibody to native p67, and had an estimated molecular mass of 110 kDa, as opposed to the calculated mass of 85,000 Da. We have used the baculovirus expression system in an attempt to express this parasite protein in a native form and thereby increase the protective capacity of the antigen. However, Spodoptera frugiperda SF21AE cells infected with recombinant virus expressed p67 as a 100-kDa molecule. The host cells exhibited a limited capacity to glycosylate this molecule to a 110-kDa form, and p67 was not exported to the surface membrane. TpM 12 did not bind to these recombinant forms but, at time points late during viral infection, reacted with a molecule of about 70 kDa. Since the bulk of insect cell-derived p67 was not expressed in an appropriate form, we tested the immunogenicity of these partially processed recombinant p67 forms in cattle. Two groups of three cattle were inoculated with antigen formulated either with saponin or Freund's adjuvant. As seen previously with NS1-p67, all animals developed high levels of anti-p67 antibodies that neutralized sporozoite infectivity in vitro, but antigen-specific T-cell proliferative responses were not detected in peripheral blood. Given the caveat of the small number of cattle analyzed, insect cell-derived p67 does not appear to be superior to NS1-p67 as an immunogen, and the latter remains the molecule of choice for the development of vaccines against East Coast fever.
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Affiliation(s)
- V Nene
- International Laboratory for Research on Animal Disease, Nairobi, Kenya
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37
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Peregrine AS, Eisler MC, Katende J, Flynn JN, Gault EA, Kinabo LD, Holmes PH. Generation of monoclonal antibodies to the anti-trypanosomal drug isometamidium. Hybridoma (Larchmt) 1994; 13:289-94. [PMID: 7806249 DOI: 10.1089/hyb.1994.13.289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Mice were immunized with either an isometamidium-human serum albumin (HSA) conjugate or an isometamidium-porcine thyroglobulin conjugate (PTG). Thereafter, monoclonal antibodies (MAbs) IL-A 1001, IL-A 1002, IL-A 1003, 5F7.B7, and 5F7.C9 were generated and selected on the basis that they recognized conjugated and unconjugated isometamidium, but lacked cross-reactivity with the carrier molecules. All five MAbs were of the IgG1 isotype. Each of the five MAbs was assessed in a competitive ELISA for isometamidium; in each case, the minimum level of detection was approximately 10 ng/ml. Each MAb exhibited approximately 0.1% cross-reactivity with the anti-trypanosomal compound diminazene. However, based on their cross-reactivity with the anti-trypanosomal compound homidium, the MAbs could be divided into two groups; IL-A 1001, IL-A 1002, and IL-A 1003, produced using an isometamidium-HSA conjugate as an immunogen, exhibited low levels of cross-reactivity (approximately 0.1%). In contrast, 5F7.B7 and 5F7.C9, produced using an isometamidium-PTG conjugate as an immunogen, exhibited high levels of cross-reactivity.
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Affiliation(s)
- A S Peregrine
- International Laboratory for Research on Animal Diseases (ILRAD), Nairobi, Kenya
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38
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Ngumi PN, Lesan AC, Williamson SM, Awich JR, Morzaria SP, Dolan TT, Shaw MK, Young AS. Isolation and preliminary characterisation of a previously unidentified Theileria parasite of cattle in Kenya. Res Vet Sci 1994; 57:1-9. [PMID: 7973080 DOI: 10.1016/0034-5288(94)90073-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A Theileria parasite was isolated from cattle on a ranch in Kenya where it caused mild theileriosis in approximately one third of the cattle exposed to natural tick challenge. The parasite was isolated by inoculation of blood into two experimental cattle. Blood from one of these cattle was used to infect two splenectomised cattle which developed high piroplasm parasitaemias and severe anaemia. A blood stabilate was prepared from one of the splenectomised cattle and produced high parasitaemias in splenectomised cattle. Immunofluorescence tests showed that the unidentified Theileria species was distinct from other African Theileria and Babesia species of cattle. The Theileria species was shown to be antigenically distinct by means of species-specific monoclonal antibodies. The piroplasma stage was relatively large for a Theileria parasite and erythrocyte infections were usually associated with veils and bars. The salivary glands of Rhipicephalus appendiculatus, R pulchellus, R evertsi and Amblyomma variegatum fed on parasitaemic cattle did not become infected and these ticks failed to transmit the parasite. It was concluded that this parasite represented a new species of cattle Theileria in Kenya.
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Affiliation(s)
- P N Ngumi
- Protozoology Division, National Veterinary Research Centre, Muguga, Kenya
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39
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40
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Bishop RP, Sohanpal BK, Morzaria SP. Cloning and characterisation of a repetitive DNA sequence from Theileria mutans: application as a species-specific probe. Parasitol Res 1994; 80:33-41. [PMID: 8153123 DOI: 10.1007/bf00932621] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Repetitive DNA sequences were isolated from a Theileria mutans genomic library by screening with T. mutans total DNA. DNA sequence analysis demonstrated that a section of one of the clones contained a complex series of overlapping perfect repeats ranging between 99 and 20 bp in size. The T. mutans repetitive sequence did not contain large open reading frames (ORFs), unlike T. parva Tpr repetitive DNA sequences. When used as a hybridisation probe the repetitive sequence revealed restriction-fragment-length polymorphisms (RFLPs) between the EcoRI-digested DNAs of two T. mutans stocks. The T. mutans repetitive probe gave a signal with 1 ng of purified T. mutans piroplasm DNA and detected T. mutans sequences in whole-blood DNA isolated from an experimentally infected animal when the piroplasm parasitaemia was equal to or above 0.4%. Oligonucleotide primers derived from the repetitive sequence allowed more sensitive detection of T. mutans DNA by polymerase chain reaction (PCR) amplification. Using the PCR, T. mutans DNA was amplified from an experimentally infected animal with a parasitaemia of < 0.1%.
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Affiliation(s)
- R P Bishop
- International Laboratory for Research on Animal Diseases, Nairobi, Kenya
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41
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Kappmeyer LS, Perryman LE, Knowles DP. A Babesia equi gene encodes a surface protein with homology to Theileria species. Mol Biochem Parasitol 1993; 62:121-4. [PMID: 8114813 DOI: 10.1016/0166-6851(93)90185-z] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- L S Kappmeyer
- Animal Disease Research Unit, Washington State University, Pullman 99164-7030
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42
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Mamman M, Katende J, Moloo SK, Peregrine AS. Variation in sensitivity of Trypanosoma congolense to diminazene during the early phase of tsetse-transmitted infection in goats. Vet Parasitol 1993; 50:1-14. [PMID: 8291183 DOI: 10.1016/0304-4017(93)90002-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Twenty-five goats were randomly allocated to five groups of five animals each and infected with Trypanosoma congolense IL 3274 via the bites of infected Glossina morsitans centralis. At intervals of 1, 4, 8, 12 or 19 days following infection, each group of five animals was treated intramuscularly with diminazene aceturate at a dose of 7.0 mg kg-1 body weight (b.w.). While treatment on Day 1 eliminated infections in all five goats, treatment on Day 19 did not cure any of the animals; in groups treated 4, 8 or 12 days following infection, two of five goats in each group were cured. Since the alteration in apparent resistance of T. congolense IL 3274 between Day 1 and Day 19 could have been due to alteration in expression of drug resistance by trypanosomes as the population expanded, the experiment was repeated using trypanosomes that reappeared in the animals that had been treated with diminazene aceturate on Day 19. On Day 36, when all five animals were parasitaemic, five groups of teneral G. m. centralis, each containing 160 flies, were fed on one occasion on each of the five goats (one group of testse flies per goat). Thereafter, each group of tsetse flies was maintained on clean rabbits. When infective, five flies from each group were allowed to feed on two naive goats each (i.e. two goats per group of tsetse flies). One animal in each pair was treated 24 h after infection with diminazene aceturate at a dose of 7.0 mg kg-1 b.w., the other was treated on Day 19, when parasitaemic, with the same drug dosage. As before, treatment 24 h following infection eliminated infections in all animals, but when treatment was delayed until Day 19, trypanosomes in all animals were refractory to treatment. Thus, although tsetse flies were infected with trypanosomes that had arisen in infected goats following treatment with diminazene aceturate at a dose of 7.0 mg kg-1 b.w., when the same flies were allowed to feed on clean goats, the resultant infections were sensitive to treatment with the same drug dosage when administered 24 h following infection. These data therefore indicate that there is a significant alteration in diminazene sensitivity of IL 3274 between Day 1 and Day 19 and that this is associated with an alteration in the resistance phenotype of the trypanosomes.
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Affiliation(s)
- M Mamman
- International Laboratory for Research on Animal Diseases (ILRAD), Nairobi, Kenya
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43
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Voigt WP, Young AS, Mwaura SN, Nyaga SG, Njihia GM, Mwakima FN, Morzaria SP. In vitro feeding of instars of the ixodid tick Amblyomma variegatum on skin membranes and its application to the transmission of Theileria mutans and Cowdria ruminatium. Parasitology 1993; 107 ( Pt 3):257-63. [PMID: 8233589 DOI: 10.1017/s0031182000079233] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
An in vitro feeding method using rabbit or cattle skin membranes, applied successfully to all stages (larvae, nymphae and adults) of the ioxodid tick, Amblyomma variegatum, is described. The feeding apparatus consisted of a blood container with a membrane placed on top of a tick containment unit. A carbon dioxide atmosphere of between 5 and 10% and a temperature of 37 degrees C were used as stimulants for the attachment of the ticks. High CO2 concentrations in the atmosphere improved the feeding success of all instars. The effect of anticoagulation methods for the bloodmeal was investigated, and heparinized blood was found to be the most suitable for tick feeding. When the bloodmeal was replaced by tissue culture medium for feeding nymphs the subsequent moulting success was reduced. Adult ticks of both sexes remained attached for up to 16 days, until completion of their bloodmeals. All stages of the tick fed on whole blood in the artificial feeding system and all reached engorged weights less than those achieved by control ticks fed on experimental animals. A large proportion of ticks, fed artificially on whole blood, moulted or laid eggs successfully. The method was successfully applied for the transmission of Theileria mutans and Cowdria ruminantium to cattle.
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Affiliation(s)
- W P Voigt
- International Laboratory for Research on Animal Diseases, Nairobi, Kenya
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44
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Deem S, Perry B, Katende J, McDermott J, Mahan S, Maloo S, Morzaria S, Musoke A, Rowlands G. Variations in prevalence rates of tick-borne diseases in Zebu cattle by agroecological zone: implications for East Coast fever immunization. Prev Vet Med 1993. [DOI: 10.1016/0167-5877(93)90064-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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45
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Dickson J, Shiels BR. Antigenic diversity of a major merozoite surface molecule in Theileria annulata. Mol Biochem Parasitol 1993; 57:55-64. [PMID: 8426616 DOI: 10.1016/0166-6851(93)90243-q] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The 30-kDa merozoite surface antigen of Theileria annulata (Ankara) has been characterised by using merozoites derived from differentiating macroschizont-infected cloned cell lines. This molecule was found to be 1 of the major polypeptides in extracts of both merozoites and piroplasms and was strongly detected by serum from an immune cow. Analysis of merozoite extracts derived from cloned cell lines infected with parasites of different genotypes detected 2 forms of this molecule, with respective molecular masses of 30 kDa and 32 kDa. These 2 molecules were shown to be related to each other by peptide mapping. In addition to the observed size differences, the molecules were found to be antigenically divergent. Periodate treatment of western blots demonstrated that at least 1 of the variable antigenic determinants was generated by secondary modification of the polypeptide and that a large amount of the antibody reactivity was directed against similar moieties. Parasite stocks isolated from different geographical regions were distinguished by analysis of the molecules within the 30-32-kDa molecular region. The relationship between T. annulata molecules and similar antigens described for other Theileria species is discussed.
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Affiliation(s)
- J Dickson
- Department of Veterinary Parasitology, University of Glasgow, Scotland, UK
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46
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Musoke A, Morzaria S, Nkonge C, Jones E, Nene V. A recombinant sporozoite surface antigen of Theileria parva induces protection in cattle. Proc Natl Acad Sci U S A 1992; 89:514-8. [PMID: 1731322 PMCID: PMC48269 DOI: 10.1073/pnas.89.2.514] [Citation(s) in RCA: 87] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
At present immunization against Theileria parva is by infection with live sporozoites and simultaneous treatment with a long-acting oxytetracycline. This method has major limitations in that live organisms are used and the immunity engendered is parasite stock specific. In an attempt to develop an alternative immunization procedure, the gene encoding p67, a major surface antigen of sporozoites, has been expressed by using the plasmid expression vector pMG1. The gene, which has been characterized previously, encodes 709 amino acid residues, contains a single intron of 29 base pairs, and is only transcribed during sporogony. The recombinant p67 sequences were fused to the first 85 amino acid residues derived from a nonstructural gene (NS1) of influenza virus A. Immunization with a partially purified recombinant antigen emulsified in 3% saponin induced sporozoite neutralizing antibodies in cattle and provided protection in six of nine animals on homologous challenge with T. parva sporozoites. This recombinant antigen is therefore a candidate for development of a vaccine against T. parva.
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Affiliation(s)
- A Musoke
- International Laboratory for Research on Animal Diseases, Nairobi, Kenya
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47
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Kawazu S, Sugimoto C, Kamio T, Fujisaki K. Antigenic differences between Japanese Theileria sergenti and other benign Theileria species of cattle from Australia (T. buffeli) and Britain (T. orientalis). Parasitol Res 1992; 78:130-5. [PMID: 1557325 DOI: 10.1007/bf00931654] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Serological comparisons among piroplasm antigens of the benign Theileria species of cattle from Japan, Australia and Britain, which are frequently referred to as T. sergenti, T. buffeli and T. orientalis, were carried out. The results obtained from comparative enzyme-liked immunosorbent assay (ELISA) using sera from infected cattle suggest that T. sergenti could be differentiated from both T. buffeli and T. orientalis by their serological dissimilarities. Western blotting combined with two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) revealed that both the 33-kDa piroplasm protein of T. sergenti and the similar 34-kDa protein of T. buffeli and T. orientalis corresponded to immuno-dominant antigens against cattle. The other 32-kDa proteins of . T. buffeli and T. orientalis also represented immunodominant antigens. Cross-reactivities of the 32-and 34-kDa proteins were observed between T. buffeli and T. orientalis, whereas the 33-kDa protein of T. sergenti could be differentiated from the similar 34-kDa proteins of T. buffeli/orientalis. The present study suggests that T. sergenti should be separated from T. buffeli and T. orientalis on the basis of their serological dissimilarities.
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Affiliation(s)
- S Kawazu
- National Institute of Animal Health, Ibaraki, Japan
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Sugimoto C, Kawazu S, Kamio T, Fujisaki K. Protein analysis of Theileria sergenti/buffeli/orientalis piroplasms by two-dimensional polyacrylamide gel electrophoresis. Parasitology 1991; 102 Pt 3:341-6. [PMID: 1907727 DOI: 10.1017/s0031182000064283] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Proteins of the piroplasms of Theileria sergenti, T. buffeli and T. orientalis were analysed by two-dimensional polyacrylamide gel electrophoresis. Protein spot patterns of T. buffeli and T. orientalis were identical except for a few minor proteins, whereas spot patterns of two T. sergenti stocks were differentiated from those of T. buffeli and T. orientalis by a characteristic set of proteins including a major protein of molecular weight 33-34 kDa. This result indicates that Japanese T. sergenti can be phenotypically distinguishable from European and Australia Theileria species; T. orientalis and T. buffeli.
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Affiliation(s)
- C Sugimoto
- National Institute of Animal Health, Ibaraki, Japan
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