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Schmuckli-Maurer J, Casanova C, Schmied S, Affentranger S, Parvanova I, Kang'a S, Nene V, Katzer F, McKeever D, Müller J, Bishop R, Pain A, Dobbelaere DAE. Expression analysis of the Theileria parva subtelomere-encoded variable secreted protein gene family. PLoS One 2009; 4:e4839. [PMID: 19325907 PMCID: PMC2657828 DOI: 10.1371/journal.pone.0004839] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Accepted: 02/04/2009] [Indexed: 11/23/2022] Open
Abstract
Background The intracellular protozoan parasite Theileria parva transforms bovine lymphocytes inducing uncontrolled proliferation. Proteins released from the parasite are assumed to contribute to phenotypic changes of the host cell and parasite persistence. With 85 members, genes encoding subtelomeric variable secreted proteins (SVSPs) form the largest gene family in T. parva. The majority of SVSPs contain predicted signal peptides, suggesting secretion into the host cell cytoplasm. Methodology/Principal Findings We analysed SVSP expression in T. parva-transformed cell lines established in vitro by infection of T or B lymphocytes with cloned T. parva parasites. Microarray and quantitative real-time PCR analysis revealed mRNA expression for a wide range of SVSP genes. The pattern of mRNA expression was largely defined by the parasite genotype and not by host background or cell type, and found to be relatively stable in vitro over a period of two months. Interestingly, immunofluorescence analysis carried out on cell lines established from a cloned parasite showed that expression of a single SVSP encoded by TP03_0882 is limited to only a small percentage of parasites. Epitope-tagged TP03_0882 expressed in mammalian cells was found to translocate into the nucleus, a process that could be attributed to two different nuclear localisation signals. Conclusions Our analysis reveals a complex pattern of Theileria SVSP mRNA expression, which depends on the parasite genotype. Whereas in cell lines established from a cloned parasite transcripts can be found corresponding to a wide range of SVSP genes, only a minority of parasites appear to express a particular SVSP protein. The fact that a number of SVSPs contain functional nuclear localisation signals suggests that proteins released from the parasite could contribute to phenotypic changes of the host cell. This initial characterisation will facilitate future studies on the regulation of SVSP gene expression and the potential biological role of these enigmatic proteins.
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Affiliation(s)
| | - Carlo Casanova
- Molecular Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Stéfanie Schmied
- Molecular Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Sarah Affentranger
- Molecular Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Iana Parvanova
- Molecular Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Simon Kang'a
- The Institute for Genomic Research (TIGR), Rockville, Maryland, United States of America
| | - Vishvanath Nene
- The Institute for Genomic Research (TIGR), Rockville, Maryland, United States of America
| | - Frank Katzer
- Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | - Declan McKeever
- Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom
| | - Joachim Müller
- Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Richard Bishop
- International Livestock Research Institute, Nairobi, Kenya
| | - Arnab Pain
- Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Dirk A. E. Dobbelaere
- Molecular Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
- * E-mail:
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Rocchi MS, Ballingall KT, Ngugi D, MacHugh ND, McKeever DJ. A rapid and sensitive intracellular flow cytometric assay to identify Theileria parva infection within target cells. Parasitology 2007; 135:195-201. [PMID: 17892619 PMCID: PMC2628746 DOI: 10.1017/s0031182007003678] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Theileria parva is an intracellular protozoan parasite transmitted by ticks that causes a fatal lymphoproliferative disease of cattle known as East Coast Fever. Vaccination against the disease currently relies on inoculation of the infective sporozoite stage of the parasite and simultaneous treatment with long-acting formulations of oxytetracycline. Sporozoites are maintained as frozen stabilates of triturated infected ticks and the method requires accurate titration of stabilates to determine appropriate dose rates. Titration has traditionally been undertaken in cattle and requires large numbers of animals because of individual variation in susceptibility to infection. An alternative tissue culture-based method is laborious and time consuming. We have developed a flow cytometric method for quantifying the infectivity of sporozoite stabilates in vitro based on the detection of intracellular parasite antigen. The method allows clear identification of parasitized cells with a high degree of sensitivity and specificity. Analysis of infected cells between 48 and 72 h post-infection clearly defines the potential transforming capability of different stabilates.
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Affiliation(s)
- M S Rocchi
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, Scotland.
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Konnai S, Yamada S, Imamura S, Simuunza M, Chembensof M, Chota A, Nambota A, Ohashi K, Onuma M. Attachment Duration Required forRhipicephalus appendiculatusto TransmitTheileria parvato the Host. Vector Borne Zoonotic Dis 2007; 7:241-8. [PMID: 17627444 DOI: 10.1089/vbz.2006.0616] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Theileria parva, the agent of East Coast fever (ECF), is transmitted to the host during the blood meal feeding of Rhipicephalus appendiculatus ticks. In order to investigate the relationship between the attachment duration of R. appendiculatus and the transmission of T. parva, infected adult ticks were allowed to attach to naive mice for variable lengths of time. Attached ticks and host animal's back skin biopsies from the tick attachment site were collected daily, starting from 24 hours post-tick attachment, and used for seminested polymerase chain reaction (PCR) detection of T. parva. T. parva-infected ticks started to transmit the parasites from 72 hours post-tick attachment. As expected, the transmission of T. parva from ticks to mouse skin increased with duration of tick attachment. Transmission of the parasites was 77.7%, 100%, 85.5%, and 100% on day 4, 5, 6, and 7 post-tick attachment, respectively, as could be detected from mice skin biopsies taken from T. parva-infected ticks' attachment sites. These results have important implications for our understanding of early events in the transmission of T. parva and would help in the development of effective pharmacologic substances and/or vaccines against ticks.
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Affiliation(s)
- Satoru Konnai
- Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
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Mbassa GK, Kipanyula MJ, Mellau LSB, Mwamakali ED, Bulegeya FR, Kauto-Mboni K. Theileria parva infection in calves causes massive lymphocyte death in the thymus, spleen and lymph nodes without initial proliferation. Vet Parasitol 2006; 142:260-70. [PMID: 16962242 DOI: 10.1016/j.vetpar.2006.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 06/24/2006] [Accepted: 07/06/2006] [Indexed: 11/21/2022]
Abstract
In a study of trends and magnitudes of lymphocytes proliferation, destruction or apoptosis eleven 3-month-old healthy calves were experimentally infected with the protozoan parasite Theileria parva, which is reported to cause lymphocyte proliferation. Four control calves were not infected. Infected and non-infected calves were sacrificed on days 9, 12, 16, 19, 23, 24 and 25 to examine lymphoid tissue changes and lymphocyte proliferation, apoptosis or necrosis in the thymus, spleen and lymph nodes. All infected calves developed severe East Coast fever, with enlargement of lymph nodes, dyspnoea, high fever and pulmonary oedema. Lymphocyte proliferation was not observed in lymph nodes, thymus and spleen; instead there were massive deaths of lymphocytes and other cells. The terminal severe disease caused massive lymphoid parenchyma coagulation terminating with caseation, organs and cells being undeterminable histologically. Tissues surrounding the lymph nodes were oedematous. Lymph node and thymus parenchyma were caseated and cortices and medulla indistinguishable because of severe lymphocyte and accessory cell deaths. The lymph node fibrous reticular stroma was necrotic and caseated. Lymphoid follicles in lymph nodes degenerated and lacked germinal centres. Lymph nodes, spleen and thymus were grossly enlarged, hardened, potato or cheese like, but microscopically very hypocellular and in the terminal disease acellular because of massive lymphocytes destruction. In the thymus there was extensive thymocyte and epithelioid cell necrosis and loss of distinction between cortex and medulla. The spleen white and red pulps were indistinguishable because of extensive lymphoid cell necrosis. The white pulp degenerated more than the red pulp. The massive lymphocyte deaths in the lymph nodes, thymus and spleen, without lymphocyte proliferation in this T. parva infection in calves leads to a conclusion that this parasite is lympho-destructive and lympho-degenerative in vivo rather than lympho-proliferative.
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Affiliation(s)
- G K Mbassa
- Department of Veterinary Anatomy, Faculty of Veterinary Medicine, Sokoine University of Agriculture, P.O. Box 3016, Morogoro, Tanzania.
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5
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Walker AR, Katzer F, Ngugi D, McKeever D. Cloned Theileria parva produces lesser infections in ticks compared to uncloned T. parva despite similar infections in cattle. ACTA ACUST UNITED AC 2006; 73:157-62. [PMID: 16958269 PMCID: PMC2628563 DOI: 10.4102/ojvr.v73i2.163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Experimental transmissions of cloned Theileria parva in cattle with Rhipicephalus appendiculatus ticks were compared to transmissions with uncloned T. parva during studies on the potential for genetic recombination during syngamy of Theileria to produce antigenic diversity for evasion of bovine immunity. Prevalence and abundance of T. parva infection in adult ticks, which resulted from the feeding of nymphs on the calves, were significantly higher in the uncloned compared to the cloned T. parva. Development of sporoblasts of T. parva in the ticks to produce infective sporozoites was similar. There was no statistically significant difference in the clinical course of infection in cattle between cloned and uncloned T. parva. It was concluded that cloned T. parva has characteristics that reduce its viability during the tick stages of its life cycle.
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Affiliation(s)
- A R Walker
- Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin EH25 9RG, Scotland, UK.
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Mbao V, Berkvens D, Dolan T, Speybroeck N, Brandt J, Dorny P, Van den Bossche P, Marcotty T. Infectivity of Theileria parva sporozoites following cryopreservation in four suspension media and multiple refreezing: evaluation by in vitro titration. Onderstepoort J Vet Res 2006; 73:207-13. [PMID: 17058443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023] Open
Abstract
Theileria parva sporozoite stabilates are used for immunizing cattle against East Coast fever and in in vitro sporozoite neutralization assays. In this study, we attempted to identify a cheaper freezing medium and quantified the infectivity loss of sporozoites due to refreezing of stabilates, using an in vitro technique. Pools of stabilates prepared using Minimum Essential Medium (MEM), Roswell Park Memorial Institute (RPMI 1640), foetal calf serum (FCS) and phosphate-buffered saline (PBS) were compared. All were supplemented with bovine serum albumin except the FCS. RPMI 1640 was as effective as MEM in maintaining sporozoite infectivity while the infectivity in PBS and FCS reached only 59% and 67%, respectively. In a second experiment, a stabiiate based on MEM was subjected to several freeze-thaw cycles including various holding times on ice between thawing and refreezing. Refrozen stabilate gave an average sporozoite infectivity loss of 35% per cycle. The results indicate that RPMI can be used as a cheaper freezing medium for T. parva stabilates and that refrozen stabilate doses need to be adjusted for the 35% loss of infectivity.
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Affiliation(s)
- V Mbao
- Department of Veterinary and Livestock Development, Ministry of Agriculture and Cooperatives, P.O. Box 670050, Mazabuka, Zambia
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Casanova CL, Xue G, Taracha EL, Dobbelaere DA. Post-translational signal peptide cleavage controls differential epitope recognition in the QP-rich domain of recombinant Theileria parva PIM. Mol Biochem Parasitol 2006; 149:144-54. [PMID: 16806529 DOI: 10.1016/j.molbiopara.2006.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2006] [Revised: 05/09/2006] [Accepted: 05/10/2006] [Indexed: 11/21/2022]
Abstract
The presence of the schizont stage of the obligate intracellular parasites Theileria parva or T. annulata in the cytoplasm of an infected leukocyte results in host cell transformation via a mechanism that has not yet been elucidated. Proteins, secreted by the schizont, or expressed on its surface, are of interest as they can interact with host cell molecules that regulate host cell proliferation and/or survival. The major schizont surface protein is the polymorphic immunodominant molecule, PIM, which contains a large glutamine- and proline-rich domain (QP-rd) that protrudes into the host cell cytoplasm. Analyzing QP-rd generated by in vitro transcription/translation, we found that the signal peptide was efficiently cleaved post-translationally upon addition of T cell lysate or canine pancreatic microsomes, whereas signal peptide cleavage of a control protein only occurred cotranslationally and in the presence of microsomal membranes. The QP-rd of PIM migrated anomalously in SDS-PAGE and removal of the 19 amino acids corresponding to the predicted signal peptide caused a decrease in apparent molecular mass of 24kDa. The molecule was analyzed using monoclonal antibodies that recognize a set of previously defined PIM epitopes. Depending on the presence or the absence of the signal peptide, two conformational states could be demonstrated that are differentially recognized, with N-terminal epitopes becoming readily accessible upon signal peptide removal, and C-terminal epitopes becoming masked. Similar observations were made when the QP-rd of PIM was expressed in bacteria. Our observations could also be of relevance to other schizont proteins. A recent analysis of the proteomes of T. parva and T. annulata revealed the presence of a large family of potentially secreted proteins, characterized by the presence of large stretches of amino acids that are also particularly rich in QP-residues.
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Affiliation(s)
- Carlo L Casanova
- Molecular Pathology, Vetsuisse Faculty, University of Bern, CH-3012 Bern, Switzerland
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8
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Fandamu P, Duchateau L, Speybroeck N, Mulumba M, Berkvens D. East Coast fever and multiple El Niño Southern oscillation ranks. Vet Parasitol 2005; 135:147-52. [PMID: 16213095 DOI: 10.1016/j.vetpar.2005.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2005] [Revised: 08/30/2005] [Accepted: 09/01/2005] [Indexed: 11/30/2022]
Abstract
East Coast fever (ECF), a tick-borne disease of cattle, is a major constraint to livestock development in Africa in general and southern Zambia in particular. Understanding the transmission patterns of this disease complex is very difficult as shown by previous studies in southern and eastern Zambia due to the interplay of risk factors. In this long-term study, we investigated whether global weather changes had any influence on disease transmission in traditionally kept cattle in southern Zambia. The results from this study show a strong association between increased Theileria parva contacts in cattle and the presence of El Niño, clearly linking a simple climatic index to disease outbreaks. We therefore propose that in southern Zambia, the simple and readily available multiple El Niño Southern oscillation index (MEI) ranks be used in planning ECF control programmes and early warning.
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Affiliation(s)
- P Fandamu
- Department of Veterinary and Livestock Development, Mazabuka Veterinary Research Station, P.O. Box 670050, Mazabuka, Zambia
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Pain A, Renauld H, Berriman M, Murphy L, Yeats CA, Weir W, Kerhornou A, Aslett M, Bishop R, Bouchier C, Cochet M, Coulson RMR, Cronin A, de Villiers EP, Fraser A, Fosker N, Gardner M, Goble A, Griffiths-Jones S, Harris DE, Katzer F, Larke N, Lord A, Maser P, McKellar S, Mooney P, Morton F, Nene V, O'Neil S, Price C, Quail MA, Rabbinowitsch E, Rawlings ND, Rutter S, Saunders D, Seeger K, Shah T, Squares R, Squares S, Tivey A, Walker AR, Woodward J, Dobbelaere DAE, Langsley G, Rajandream MA, McKeever D, Shiels B, Tait A, Barrell B, Hall N. Genome of the Host-Cell Transforming Parasite Theileria annulata Compared with T. parva. Science 2005; 309:131-3. [PMID: 15994557 DOI: 10.1126/science.1110418] [Citation(s) in RCA: 242] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Theileria annulata and T. parva are closely related protozoan parasites that cause lymphoproliferative diseases of cattle. We sequenced the genome of T. annulata and compared it with that of T. parva to understand the mechanisms underlying transformation and tropism. Despite high conservation of gene sequences and synteny, the analysis reveals unequally expanded gene families and species-specific genes. We also identify divergent families of putative secreted polypeptides that may reduce immune recognition, candidate regulators of host-cell transformation, and a Theileria-specific protein domain [frequently associated in Theileria (FAINT)] present in a large number of secreted proteins.
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Affiliation(s)
- Arnab Pain
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK.
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Gardner MJ, Bishop R, Shah T, de Villiers EP, Carlton JM, Hall N, Ren Q, Paulsen IT, Pain A, Berriman M, Wilson RJM, Sato S, Ralph SA, Mann DJ, Xiong Z, Shallom SJ, Weidman J, Jiang L, Lynn J, Weaver B, Shoaibi A, Domingo AR, Wasawo D, Crabtree J, Wortman JR, Haas B, Angiuoli SV, Creasy TH, Lu C, Suh B, Silva JC, Utterback TR, Feldblyum TV, Pertea M, Allen J, Nierman WC, Taracha ELN, Salzberg SL, White OR, Fitzhugh HA, Morzaria S, Venter JC, Fraser CM, Nene V. Genome Sequence of Theileria parva, a Bovine Pathogen That Transforms Lymphocytes. Science 2005; 309:134-7. [PMID: 15994558 DOI: 10.1126/science.1110439] [Citation(s) in RCA: 258] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
We report the genome sequence of Theileria parva, an apicomplexan pathogen causing economic losses to smallholder farmers in Africa. The parasite chromosomes exhibit limited conservation of gene synteny with Plasmodium falciparum, and its plastid-like genome represents the first example where all apicoplast genes are encoded on one DNA strand. We tentatively identify proteins that facilitate parasite segregation during host cell cytokinesis and contribute to persistent infection of transformed host cells. Several biosynthetic pathways are incomplete or absent, suggesting substantial metabolic dependence on the host cell. One protein family that may generate parasite antigenic diversity is not telomere-associated.
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Affiliation(s)
- Malcolm J Gardner
- Institute for Genomic Research (TIGR), 9712 Medical Center Drive, Rockville, MD 20850, USA.
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11
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Nene V, Lee D, Kang'a S, Skilton R, Shah T, de Villiers E, Mwaura S, Taylor D, Quackenbush J, Bishop R. Genes transcribed in the salivary glands of female Rhipicephalus appendiculatus ticks infected with Theileria parva. Insect Biochem Mol Biol 2004; 34:1117-1128. [PMID: 15475305 DOI: 10.1016/j.ibmb.2004.07.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 06/30/2004] [Accepted: 07/01/2004] [Indexed: 05/24/2023]
Abstract
We describe the generation of an auto-annotated index of genes that are expressed in the salivary glands of four-day fed female adult Rhipicephalus appendiculatus ticks. A total of 9162 EST sequences were derived from an uninfected tick cDNA library and 9844 ESTs were from a cDNA library from ticks infected with Theileria parva, which develop in type III salivary gland acini. There were no major differences between abundantly expressed ESTs from the two cDNA libraries, although there was evidence for an up-regulation in the expression of some glycine-rich proteins in infected salivary glands. Gene ontology terms were also assigned to sequences in the index and those with potential enzyme function were linked to the Kyoto encyclopedia of genes and genomes database, allowing reconstruction of metabolic pathways. Several genes code for previously characterized tick proteins such as receptors for myokinin or ecdysteroid and an immunosuppressive protein. cDNAs coding for homologs of heme-lipoproteins which are major components of tick hemolymph were identified by searching the database with published N-terminal peptide sequence data derived from biochemically purified Boophilus microplus proteins. The EST data will be a useful resource for construction of microarrays to probe vector biology, vector-host and vector-pathogen interactions and to underpin gene identification via proteomics approaches.
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Affiliation(s)
- Vishvanath Nene
- Parasite Genomics Department, The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA.
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Guergnon J, Dessauge F, Langsley G, Garcia A. Apoptosis of Theileria-infected lymphocytes induced upon parasite death involves activation of caspases 9 and 3. Biochimie 2004; 85:771-6. [PMID: 14585544 DOI: 10.1016/j.biochi.2003.09.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The intracellular parasite Theileria parva (T. parva) can infect bovine B and T-lymphocytes. T. parva-infected cells become transformed, and they survive and proliferate independently of exogenous growth factors. In vivo the uncontrolled cellular proliferation associated with lymphocyte transformation underlies the pathogenesis of the disease called East Coast Fever. The transformed state of parasitised cells can be reversed upon elimination of the parasite by specific theilericide drugs. In this study we found that elimination of the parasite by buparvaquone induces apoptosis of transformed B and CD8(+) T-lymphocytes. Apoptosis is accompanied by the activation of caspase 9 and caspase 3 and processing of poly(ADP ribose) polymerase and is inhibited by Z-VAD a general caspase inhibitor. Based on these observations, we propose that the lack of activation of a caspase 9 > caspase 3 > poly(ADP ribose) polymerase pathway is important and protects T. parva-transformed cells from spontaneous apoptosis.
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Affiliation(s)
- Julien Guergnon
- Département de Parasitologie, URA CNRS 2581, Institut Pasteur, 25, rue du Dr Roux, 75015 Paris, France.
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Abstract
The effects of holding temperature, pH and medium on the infectivity of Theileria parva sporozoites were investigated using an in vitro infectivity assay. The sporozoite infectivity lasted for 72 h at a holding temperature of 4 C but for only 24 h at 24 degrees C. Sporozoite infectivity was found to be sensitive to pH variations and sporozoites were most infective between pH 7 and pH 8. There was a significant loss in infectivity at pH 5 and infectivity was almost totally abolished at pH 9. Theileria parva sporozoites are usually held and manipulated in Eagle's minimum essential medium (MEM) with Earles' salts. In this study. Leibovitz-15 supplemented with 15% fetal bovine serum gave a significantly better infectivity than Eagle's MEM (3.8 log units versus 1.0 log units) or any other medium. The importance of proper management of the T. parva sporozoite environment in the laboratory or field is emphasized by the findings in these studies and might also explain some of the failures of vaccination when the pH of the holding medium was allowed to deteriorate.
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Affiliation(s)
- E N Kimbita
- International Livestock Research Institute, Department of Veterinary Microbiology and Parasitology, Sokoine University of Agriculture, PO Box 3019, Morogoro, Tanzania.
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Musyoki JM, Osir EO, Kiara HK, Kokwaro ED. Comparative studies on the infectivity of Theileria parva in ticks fed in vitro and those fed on cattle. Exp Appl Acarol 2004; 32:51-67. [PMID: 15139272 DOI: 10.1023/b:appa.0000018159.47700.e4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Nymphs of the brown ear tick, Rhipicephalus appendiculatus, were fed on heparinised bovine blood infected with Theileria parva parasites in an in vitro feeding system consisting of rabbit skin membranes. The main feeding and development parameters such as the mean attachment rate, feeding duration and engorgement weights of membrane-fed ticks were not significantly different from nymphs fed on cattle. The moulting rate was also comparable although a slight significant difference was observed. Assessment of infection prevalence and abundance with T. parva in adults indicated that the membrane-fed ticks acquired infection to the same level as those fed on cattle. Stabilates prepared from both the membrane- and cattle-fed adult ticks were found to be infective and caused severe reactions in susceptible cattle. When the immunised cattle were challenged with a lethal homologous dose of T. parva (Marikebuni), they were found to be immune.
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Guergnon J, Chaussepied M, Sopp P, Lizundia R, Moreau MF, Blumen B, Werling D, Howard CJ, Langsley G. A tumour necrosis factor alpha autocrine loop contributes to proliferation and nuclear factor-kappaB activation of Theileria parva-transformed B cells. Cell Microbiol 2003; 5:709-16. [PMID: 12969376 DOI: 10.1046/j.1462-5822.2003.00314.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Theileria infection of bovine leucocytes induces uncontrolled proliferation and a transformed phenotype comparable to tumour cells. Infected cells have many characteristics of activated leucocytes and use autocrine loops to augment proliferation. We have shown previously that, in infected B cells, PI3-K controls a granulocyte-macrophage colony-stimulating factor (GM-CSF) autocrine loop to increase both proliferation and activation of the activator protein 1 (AP-1) transcription factor. We show here that the same infected B cells also use a tumour necrosis factor (TNF) alpha autocrine loop that again contributes to proliferation and augments nuclear factor (NF)-kappaB activation. Interestingly, both pharmacological inhibition of TNF synthesis and neutralizing anti-TNF antibodies lead to a reduction in proliferation and a 50% drop in NF-kappaB activation, without inducing apoptosis.
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Affiliation(s)
- Julien Guergnon
- Laboratoire de Signalisation Immunoparasitaire, URA CNRS 1960, Département de Parasitologie, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France
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16
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Abstract
There has been an increase in the introduction of game animals, including African buffaloes, into the Highveld of Zimbabwe to establish private game reserves on condition that they are confined in separate and secured paddocks. Owing to shortages of pastures cattle were grazed in buffalo-grazed paddocks resulting in outbreaks of buffalo-derived theileriosis. This paper reports the results of epidemiological observations carried out on two game reserves to assess the risk of buffalo translocation. The infection rate with Theileria parasites in ticks collected from buffalo-grazed pastures was high and produced fatal theileriosis in susceptible cattle. Similarly, adult R. appendiculatus ticks artificially fed as nymphs on the buffaloes produced fatal infections in susceptible cattle. Theileria parva (Boleni), the vaccine used to immunize cattle against theileriosis, and a buffalo-derived T. parva stabilate (BV-1) were inoculated in naïve buffaloes to study the Theileria carrier-state in these animals. The two buffaloes that had received the Boleni stabilate showed no clinical theileriosis reaction; however, the ticks derived from them produced a subclinical reaction in one susceptible calf. The buffalo which had received stabilate BV-1 developed fever, high schizont parasitosis for 10 days and 15% piroplasms parasitemia. R. appendiculatus ticks fed as nymphs on this buffalo produced fatal theileriosis reaction in a susceptible calf.
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Affiliation(s)
- A A Latif
- Faculty of Science, Midrand University, P.O. Box 2986, Halfway House 1685, South Africa.
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17
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Latif AA, Hove T, Kanhai GK, Masaka S, Pegram RG. Epidemiological observations of Zimbabwean theileriosis: disease incidence and pathogenicity in susceptible cattle during Rhipicephalus appendiculatus nymphal and adult seasonal activity. Onderstepoort J Vet Res 2001; 68:187-95. [PMID: 11769350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Fifty-nine Hereford cattle susceptible to tick-borne diseases were used as tracer animals to assess the tick challenge and pathogenicity of Theileria parva under field conditions in Zimbabwe. They were moved periodically in groups of five to three commercial farms (one group consisted of four) during seasons of Rhipicephalus appendiculatus nymphal and adult activity. All tracer cattle were herded together with the farm cattle but were not dipped. The nymphal tick counts were high on two of the farms (up to 2000 per animal) but were very low on the third farm (less than ten per animal). On the three farms, 19 out of 24 (76%) tracers had patent Theileria schizonts. There was a range of clinical manifestations of theileriosis with acute and fatal infections occurring on one farm. The adult R. appendiculatus infestations during the wet season numbered 120-800 per animal on the three farms. The disease transmitted by the adults was very pathogenic on the three farms; 30 out of 35 (86%) had severe theileriosis infections. Cattle, which survived the nymphal diseases challenge, showed various degrees of immunity to subsequent T. parva challenge transmitted by adult ticks. Therefore, 13 out of 18 (72%) of these cattle had a second disease episode and the case fatality rate on the three farms was 46%. The factors which determined the epidemiological status of Theileria challenge on the farms, such as the farming systems and presence of wild animals, are discussed.
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Affiliation(s)
- A A Latif
- Faculty of Science, Midrand University, Halfway House, South Africa
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18
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Latif AA, Hove T, Kanhai GK, Masaka S. Exposure of cattle immunized with different stocks of Theileria parva to buffalo-associated Theileria challenge on two game parks in Zimbabwe. Onderstepoort J Vet Res 2001; 68:197-201. [PMID: 11769351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Eight cattle immunized with cattle-derived Theileria parva Boleni stabilate together with six susceptible controls were released in Dombawera Game Park on the Highveld of Zimbabwe. This coincided with Rhipicephalus appendiculatus nymphal activity. The cattle grazed together with African buffaloes (Syncerus caffer) and were not treated against tick infestation. The nymphal tick infestation was high, and seven of the eight immunized cattle and three of the controls had severe and fatal reactions. Subsequently, two stocks of Theileria parva to be tested for their immunizing abilities were prepared-one from adult ticks which were fed as nymphs on one of the sick control animals (Dom 268) and the other from adult ticks collected from pastures grazed by buffaloes (Bv-1). Two groups of cattle were immunized with either the Dom 268-derived strain (eight animals) or the Bv-1-derived strain (four animals). These together with three non-immunized controls, were released in Bally Vaughaun Game Park in the Highveld, where buffaloes are present, during the season of nymphal tick activity. A third group of five cattle, immunized with stabilate Bv-1, and three non-immunized controls were released at the same site during the season of adult tick activity. The nymphal and adult tick infestations of the cattle were large and more than 2000 nymphs and 1000 adult ticks were counted per animal. Cattle were treated with a pyrethroid pour-on preparation to control the tick infestation and screw-worm strike. The immunized cattle in the three groups survived the theileriosis challenge for a period of 18 months, but the non-immunized control cattle suffered a severe and fatal theileriosis 19-23 days after being placed on the pasture.
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Affiliation(s)
- A A Latif
- Faculty of Science, Midrand University, Halfway House, South Africa
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19
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Heussler VT, Küenzi P, Fraga F, Schwab RA, Hemmings BA, Dobbelaere DA. The Akt/PKB pathway is constitutively activated in Theileria-transformed leucocytes, but does not directly control constitutive NF-kappaB activation. Cell Microbiol 2001; 3:537-50. [PMID: 11488815 DOI: 10.1046/j.1462-5822.2001.00134.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The intracellular protozoan parasites Theileria parva and Theileria annulata transform leucocytes by interfering with host cell signal transduction pathways. They differ from tumour cells, however, in that the transformation process can be entirely reversed by elimination of the parasite from the host cell cytoplasm using a specific parasiticidal drug. We investigated the state of activation of Akt/PKB, a downstream target of PI3-K-generated phosphoinositides, in Theileria-transformed leucocytes. Akt/PKB is constitutively activated in a PI3-K- and parasite-dependent manner, as judged by the specific phosphorylation of key residues, in vitro kinase assays and its cellular distribution. In previous work, we demonstrated that the parasite induces constitutive activation of the transcription factor NF-kappaB, providing protection against spontaneous apoptosis that accompanies transformation. In a number of other systems, a link has been established between the PI3-K-Akt/PKB pathway and NF-kappaB activation, resulting in protection against apoptosis. In Theileria-transformed leucocytes, activation of the NF-kappaB and the PI3-K-Akt/PKB pathways are not directly linked. The PI3-K-Akt/PKB pathway does not contribute to the persistent induction of IkappaBalpha phosphorylation, NF-kappaB DNA-binding or transcriptional activity. We show that the two pathways are downregulated with different kinetics when the parasite is eliminated from the host cell cytoplasm and that NF-kappaB-dependent protection against apoptosis is not dependent on a functional PI3-K-Akt/PKB pathway. We also demonstrate that Akt/PKB contributes, at least in part, to the proliferation of Theileria-transformed T cells.
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Affiliation(s)
- V T Heussler
- Molecular Pathology, Institute of Animal Pathology, University of Berne, CH-3012 Berne, Switzerland
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20
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Kimbita EN, Silayo RS, Dolan TT. Comparison of cryoprotectants in the preservation of Theileria parva sporozoites using an in vitro infectivity assay. Trop Anim Health Prod 2001; 33:29-41. [PMID: 11234190 DOI: 10.1023/a:1010329409637] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
An in vitro infectivity assay was used to examine five cryoprotectants for their suitability for preserving Theileria parva sporozoites. All five were capable of preserving T. parva sporozoites through freezing, the optimal concentrations being 7.5% for glycerol, 5% for dimethyl sulphoxide (DMSO), poly (vinylpyrrolidone) (PVP) and poly(ethylene glycol) (PEG), and 2.5% for hydroxyethyl starch (HES). When the five cryoprotectants were compared at their optimal concentrations, using a modification of the standard method of stabilate preparation, glycerol was significantly better than the others (p < 0.05). Measurement of the effects of each cryoprotectant on the osmolality of the media revealed that glycerol and DMSO elevated the osmolality significantly (p < 0.05). Resuscitation of glycerol-preserved sporozoites required the presence of glycerol in the diluent to maintain infectivity. Studies on the effects of equilibration time in glycerol on the infectivity of sporozoites showed that those frozen immediately after mixing (2 min) were as infective as those frozen after 60 min of equilibration.
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Affiliation(s)
- E N Kimbita
- International Livestock Research Institute, Nairobi, Kenya
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21
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Baumgartner M, Chaussepied M, Moreau MF, Werling D, Davis WC, Garcia A, Langsley G. Constitutive PI3-K activity is essential for proliferation, but not survival, of Theileria parva-transformed B cells. Cell Microbiol 2000; 2:329-39. [PMID: 11207589 DOI: 10.1046/j.1462-5822.2000.00062.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Theileria is an intracellular parasite that causes lymphoproliferative disorders in cattle, and infection of leucocytes induces a transformed phenotype similar to tumour cells, but the mechanisms by which the parasite induces this phenotype are not understood. Here, we show that infected B lymphocytes display constitutive phosphoinositide 3-kinase (PI3-K) activity, which appears to be necessary for proliferation, but not survival. Importantly, we demonstrate that one mechanism by which PI3-K mediates the proliferation of infected B lymphocytes is through the induction of a granulocyte-monocyte colony-stimulating factor (GM-CSF)-dependent autocrine loop. PI3-K induction of GM-CSF appears to be at the transcriptional level and, consistently, we demonstrate that PI3-K is also involved in the constitutive induction of AP-1 and NF-kappaB, which characterizes Theileria-infected leucocytes. Taken together, our results highlight a novel strategy exploited by the intracellular parasite Theileria to induce continued proliferation of its host leucocyte.
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Affiliation(s)
- M Baumgartner
- Département d'Immunologie, Institut Pasteur, Paris, France
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22
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Abstract
The intracellular parasite Theileria parva infects and transforms bovine T-cells, inducing their uncontrolled proliferation and spread in non-lymphoid as well as lymphoid tissues. This parasite-induced transformation is the predominant factor contributing to the pathogenesis of a lymphoproliferative disease, called East Coast fever. T. parva-transformed cells become independent of antigenic stimulation or exogenous growth factors. A dissection of the signalling pathways that are activated in T. parva-infected cells shows that the parasite bypasses signalling pathways that normally emanate from the T-cell antigen receptor to induce continuous proliferation. This review concentrates on the influence of the parasite on the state of activation of the mitogen-activated protein kinase (MAPK), NF-kappaB and phosphoinositide-3-kinase (PI3-K) pathways in the host cell. Of the MAPKs, JNK, but not ERK or p38, is active, inducing constitutive activation of the transcription factors AP-1 and ATF-2. A crucial step in the transformation process is the persistent activation of the transcription factor NF-kappaB, which protects T. parva-transformed cells from spontaneous apoptosis accompanying the transformation process. Inhibitor studies also suggest an important role for the lipid kinase, PI-3K, in the continuous proliferation of T. parva-transformed lymphocytes.
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Affiliation(s)
- D A Dobbelaere
- Institute of Animal Pathology, Molecular Pathology, Berne, Switzerland.
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23
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Abstract
Ceramide is a lipid second messenger which is generated in response to stimulation of a number of surface receptors, treatment with chemotherapeutic agents, or ionising radiation. Depending on the target cell, ceramide induces diverse biological responses including apoptosis, cell-cycle arrest, differentiation, and also proliferation. We studied the effect of ceramide on the degradation of IkappaB, the cytoplasmic inhibitor of the transcription factor NF-kappaB. We show that ceramide treatment results in reduced levels of phosphorylated IkappaBalpha and degradation of both IkappaBalpha and IkappaBbeta. Ceramide synergised with okadaic acid (OA), a compound which interferes with the protein phosphatase 2A-controlled component of the NF-kappaB activation pathway, enhancing OA-induced IkappaB degradation. Ceramide also synergised with phorbol 12-myristate 13-acetate, which mimics protein kinase C activation. Finally, we show that the synergistic effect of ceramide with OA or phorbol ester can be observed in primary lymph node T-cells as well as in transformed T-cells.
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Affiliation(s)
- P C Fernandez
- Molecular Pathology, University of Berne, Länggass-strasse 122, Berne, CH-3012, Switzerland
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24
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Abstract
The sporozoites of Theileria annulata and T. parva invade bovine leukocytes, where they differentiate into schizonts. The latter can immortalize and induce fundamental changes in their host cells. T. annulata infects mainly major histocompatibility complex class II cells, whereas T. parva preferentially transforms T-lymphocytes, which proliferate continuously without the need for exogenously added growth factors. Most of the cell lines appear to be independent of a growth factor but may express several cytokines that influence the outcome of the disease. The mechanisms underlying this transformation are not well understood. The infected cells show increased activity of casein kinase II and Jun NH2-terminal kinase (JNK), whereas extracellular signal-related kinase 1 and 2 and P38 are not activated. In addition, several transcriptional factors such as NFkB and AP-1 are activated. It has been postulated that parasite proteins either expressed on the surface of the schizonts or secreted into the host cell cytoplasm may interfere with the signal-transduction pathway of the host cells. A possible candidate may the casein kinase II homologue that was identified in schizonts of both T. annulata and T. parva.
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25
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Abstract
Bovine T-cells infected by the protozoan parasite Theileria parva undergo lymphoblastoid transformation, and proliferate in an uncontrolled manner. While it has been established that the transcription factor NF-kappa B is constitutively activated in T. parva-infected T-cells, little is known about other transcription factors such as AP-1 and ATF-2. We demonstrated increased binding activity to the AP-1 and CREB/ATF-2 consensus binding sites and show that the AP-1 complex is composed of c-Jun, JunD, c-Fos, and ATF-2. The transcription factors c-Jun and ATF-2 are constitutively phosphorylated in a parasite-dependent manner. Both transcription factors can be phosphorylated by jun-NH2-terminal kinase (JNK), but ATF-2 is also a substrate for p38. We determined whether p38 is activated in T. parva-infected cells. Immunoblot analysis and inhibitor studies indicate that JNK, but not p38, is involved in ATF-2 phosphorylation. Based on these results and previous studies, we conclude that parasite interference with mitogen-activated protein kinase pathways is restricted to constitutive activation of JNK.
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Affiliation(s)
- C Botteron
- Institute of Animal Pathology, University of Berne, Switzerland
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26
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Mbassa GK, Kweka LE, Dulla PN. Immunization against East Coast Fever in field cattle with low infectivity Theileria parva stabilate--preliminary assessment. Vet Parasitol 1998; 77:41-8. [PMID: 9652382 DOI: 10.1016/s0304-4017(97)00138-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Two Theileria parva sporozoite stabilates stored at -196 degrees C, then at -70 degrees C for six weeks (stabilate 1) and more than six months (stabilate 2) were inoculated into four eight-month old male calves, 1 and 2 (stabilate 1), and 3 and 4 (stabilate 2). Calves 1 and 2 developed pyrexia, enlargement of lymph nodes, and the former died of East Coast Fever. Calves 3 and 4 showed slight enlargement of lymph nodes without fever. Lymph node smears from all calves (from day 10 to 20 post-inoculation) showed lymphoblasts, phagocytic macrophages, and schizonts. Piroplasms were detected in erythrocytes in blood smears from calves 1 and 2 but not in calves 3 and 4. Calves 2, 3 and 4 recovered without any treatment while calf 1 died of East Coast Fever on day 20. Serum samples from recovered calves taken on day 30 of the experiment were positive for antischizont antibodies to T. parva at 1:640 dilution, but pre-inoculation serum samples were negative. Stabilate 2 was used to immunize 64 Boran, Friesian, Ayrshire and crosses with Zebu cattle in four herds with 25% reduction of oxytetracycline dose. All the animals except one calf recovered without any severe reactions. The latter died of disease other than ECF after the monitoring period was over (day 24). Day 30 post-inoculation serum samples were positive for T. parva antischizont antibodies. A follow-up of the remaining animals for over one year revealed no further ECF incidences in these herds. This experiment shows the loss of infectivity of the vaccine stored at temperatures higher than -196 degrees C. dependent on the duration. However, despite the lack of clinical signs in calves 3 and 4, there was cellular response and antibody production, and the stabilate for vaccine against East Coast fever can thus be stored prior to use at higher than -196 degrees C and still maintain capability to produce antibodies in field cattle, eliminating the use of oxytetracycline and monitoring. The vaccine will be cheaper and easier to use and the requirement for liquid nitrogen in the field reduced and the scale of application of the vaccine widened.
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Affiliation(s)
- G K Mbassa
- Department of Veterinary Anatomy, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania.
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27
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Musisi FL, Quiroga JC, Njuguna LM, Kamwendo SP, Chamambala KE. Viability of Theileria parva trivalent stabilate after thawing and maintenance at 4 degrees C for up to 15 hours. Int J Parasitol 1996; 26:175-9. [PMID: 8690541 DOI: 10.1016/0020-7519(95)00118-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Two experiments were conducted to determine the effect of prolonged maintenance at 4 degrees C on thawed Theileria parva stabilates. Samples maintained at 4 degrees C for 1, 12, 15 and 18 h were all infective for cattle. Immunized cattle were able to resist potentially lethal challenges 29 days later. These results indicate that the handling of T. parva trivalent stabilates for immunization against East-Coast fever in the field should be much easier than previously envisaged.
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Affiliation(s)
- F L Musisi
- Tick-borne Disease Vaccine Production Center, Lilongwe, Malawi
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28
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Abstract
Theileria parva has been shown to infect and transform B cells and T cells at similar frequencies in vitro. However, the majority of parasitized cells in the tissues of infected cattle are alpha/beta T cells. The aim of this study was to determine whether the cell type infected with T. parva influenced the pathogenicity of the parasite. The initial approach, which involved inoculation of cattle with autologous cloned cell lines of different phenotypes, failed to resolve the issue, because of prolonged period of culture required to clone and characterize the cell lines resulted in attenuation of the cells. As an alternative approach, cattle were inoculated with purified populations of autologous cells that had been incubated in vitro with T. parva sporozoites for 48 h. As few as 3 x 10(4) peripheral blood mononuclear cells (PBMC) treated in this way were found to produce severe clinical reactions with high levels of parasitosis. Infections of similar severity were produced with purified populations of CD2+, CD4+, and CD8+ T cells. By contrast, infected B cells gave rise to mild self-limiting infections even when administered at a 10-fold-higher dose. In animals that received infected CD4+ or CD8+ T cells, the parasitized cells in the lymph nodes on day 11 of infection were all within the CD4+ and CD8+ populations, respectively, indicating that there had been minimal transfer of the parasite between cell types. Phenotypic analyses of cultures of PBMC infected in vitro with saturating concentrations of sporozoites revealed that parasitized B cells were abundant in the cultures after 1 week but were subsequently overgrown by T cells. The results of these experiments indicate that the cell type infected by T. parva influences the pathogenicity of the parasite.
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Affiliation(s)
- W I Morrison
- Institute for Animal Health, Compton, United Kingdom
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29
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Abstract
A 3-step procedure for cloning Theileria parva parasites was developed. The first step involved the in vitro infection of a fixed number of bovine lymphocytes with titrated sporozoites. The cell lines obtained from infections initiated using sporozoite/lymphocyte ratios below 1:100 were then selected for cloning as these contained schizont-infected cells, each of which was derived from infection with a single sporozoite. In the second step, these cell lines were cloned by limiting dilution. As sporozoites infect lymphocytes and transform to induce clonal multiplication, this step produced infected cell lines containing both cloned parasites and cloned lymphocytes. In the third step, the cloned cell lines were used to infect cattle and isolation of the parasite in ticks was made during piroplasm parasitaemia. Finally, sporozoites were harvested from infected ticks and used for further characterization. Sporozoites derived from cloned cell lines of T. parva Muguga, Marikebuni, Boleni, Uganda and buffalo-derived 7014 were characterized using monoclonal antibody profiles, DNA restriction fragment length polymorphism detected using repetitive and telomeric probes, in vivo infectivity and, in one case, cross-immunity studies. Additionally, several distinct schizont-infected lymphocyte clones were isolated from the Muguga, Mariakani and buffalo-derived 7014 stocks. The combined results of the characterization revealed that the cloning procedure selected clones of T. parva from the parental stocks which were known to contain a mixture of genetically different parasite populations. The cloning method and the clones generated will be of value in studies of the biology of the parasite and in elucidating the strain specificity of immune responses in cattle.
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Affiliation(s)
- S P Morzaria
- International Livestock Research Institute, Nairobi, Kenya
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30
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Kamwendo SP, Musisi FL, Trees AJ, Molyneux DH. Effects of haemagglutination (lectin) inhibitory sugars on Theileria parva infection in Rhipicephalus appendiculatus. Int J Parasitol 1995; 25:29-35. [PMID: 7797369 DOI: 10.1016/0020-7519(94)00072-v] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have previously described the presence of haemagglutinins in tissues of the tick, Rhipicephalus appendiculatus and determined their sugar specificities by inhibition experiments. In this study, haemagglutination inhibitory sugars are shown to have an effect in vivo on the abundance of Theileria parva infected salivary gland acini in Rhipicephalus appendiculatus. A significant increase (P < 0.05) was observed in T. parva acinar infection rates in the salivary glands of R. appendiculatus fed on ears of rabbits infused with melibiose and raffinose. In contrast, mannose and turanose (non-haemagglutination inhibitory sugars) did not cause elevation of T. parva acinar infection rates. The effect of melibiose in elevating acinar infections was observed when used only during T. parva maturation in the salivary glands but not during parasite pick-up from an infected bovine host. Stabilates produced from ticks with elevated acinar infections did not differ from control stabilates in infectivity to cattle, by comparison of prepatent periods to pyrexia, or parasitosis, or in the severity of reactions.
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31
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ole-MoiYoi OK, Brown WC, Iams KP, Nayar A, Tsukamoto T, Macklin MD. Evidence for the induction of casein kinase II in bovine lymphocytes transformed by the intracellular protozoan parasite Theileria parva. EMBO J 1993; 12:1621-31. [PMID: 8467809 PMCID: PMC413376 DOI: 10.1002/j.1460-2075.1993.tb05807.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Theileria parva is an obligate, intracellular, parasitic protozoan that causes East Coast fever, an acute leukemia-like disease of cattle. T. parva and the related parasite, Theileria annulata, are unique among protozoa in that their intralymphocytic stages induce transformation of bovid lymphocytes. Comparison of in vitro protein kinase activities between uninfected IL-2-dependent T lymphoblasts and T. parva-infected lymphocytes revealed a 4.7- to 12-fold increase in total phosphorylation and the induction of a group of Theileria infection-specific phosphoproteins. The enzyme that phosphorylates these substrates is a serine/threonine kinase with substrate and effector specificities of casein kinase (CK) II. Northern blot analyses revealed a 3.9- to 6.0-fold increase in CKII alpha mRNA in the infected cells relative to the controls. Furthermore, a marked increase of CKII antigen was observed on Western blots of materials prepared from the infected cell lines. The antibovine CKII antibody used in these studies immunoprecipitated a protein kinase that phosphorylated casein in a reaction that was inhibited by low (nM) quantities of heparin. Our data show marked increases of bovine CKII at the transcriptional, translational and functional levels in T. parva-infected lymphocytes, relative to quiescent cells or IL-2-dependent parental lymphoblasts. Bovine CKII thus appears to be constitutively activated in these cells and we propose that this kinase may be an important element in the signal-transducing pathways activated by Theileria in bovid lymphocytes and perhaps in some leukemic cells.
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Affiliation(s)
- O K ole-MoiYoi
- International Laboratory for Research on Animal Diseases, (ILRAD), Nairobi, Kenya
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32
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ole-MoiYoi OK, Sugimoto C, Conrad PA, Macklin MD. Cloning and characterization of the casein kinase II alpha subunit gene from the lymphocyte-transforming intracellular protozoan parasite Theileria parva. Biochemistry 1992; 31:6193-202. [PMID: 1378299 DOI: 10.1021/bi00142a004] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Theileria parva is an obligate intracellular protozoan parasite which is the causative agent of East Coast fever, an acute, leukemia-like disease of cattle. The intralymphocytic stage of the parasite induces blastogenesis and clonal expansion of quiescent bovid lymphocytes. Experiments in our laboratory have shown a marked increase of casein kinase II- (CK II-) like activity in T. parva-transformed lymphocytes. We have also detected CK II activity in purified T. parva schizonts. To explore the significance of this increase, we used a Drosophila melanogaster CK II alpha cDNA probe [Saxena et al. (1987) Mol. Cell Biol. 7, 3409-3417] to isolate a T. parva genomic clone encoding a CK II catalytic subunit. The clone contains a 1.3-kb open reading frame coding for a predicted protein of 420 amino acids (M(r) 50,200). Northern blot analysis revealed a single transcript of 1.65 kb. The deduced T. parva CK II catalytic subunit sequence shows, over 321 residues comprising the C-terminus of the molecule, extensive identity with CK II alpha and alpha' sequences from both vertebrate and invertebrate organisms. The T. parva CK II subunit amino acid sequence displays 68% identity with the Drosophila alpha subunit and 67% with the Caenorhabditis elegans alpha subunit but only 58% and 56% sequence identity with the Saccharomyces cerevisiae alpha and alpha' subunits, respectively. Comparison of the T. parva sequence with higher eukaryotic alpha and alpha' sequences reveals that it is most identical with the alpha subunit. A unique component of the T. parva CK II alpha subunit is a 99 amino acid sequence at the N-terminus, which contains a sequence motif with features characteristic of signal peptides.
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Affiliation(s)
- O K ole-MoiYoi
- International Laboratory for Research on Animal Diseases, Nairobi, Kenya
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