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Phoon WH, Bell-Sakyi L, AbuBakar S, Chang LY. Experimental infection of tick cells with Nipah virus. Trop Biomed 2023; 40:29-36. [PMID: 37356001 DOI: 10.47665/tb.40.1.009] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Nipah virus (NiV), a highly pathogenic henipavirus of the family Paramyxoviridae, which causes fatal encephalitis in 40-70% of affected patients, was first reported in Malaysia over 20 years ago. Pteropid bats are the natural hosts of henipaviruses, and ticks have been proposed as a possible link between bats and mammalian hosts. To investigate this hypothesis, infection of the tick cell line IDE8 with NiV was examined. Presence of viral RNA and antigen in the NiV-infected tick cells was confirmed. Infectious virions were recovered from NiV-infected tick cells and ultrastructural features of NiV were observed by electron microscopy. These results suggest that ticks could support NiV infection, potentially playing a role in transmission.
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Affiliation(s)
- W H Phoon
- Department of Medical Microbiology, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - L Bell-Sakyi
- Institute of Infection, Veterinary and Ecological Science, University of Liverpool, 146 Brownlow Hill, Liverpool L3 5RF, United Kingdom
| | - S AbuBakar
- Tropical Infectious Diseases Research & Education Centre, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
| | - L Y Chang
- Department of Medical Microbiology, Universiti Malaya, 50603 Kuala Lumpur, Malaysia
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2
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Khoo J, Husin N, Lim F, Zulkifli M, Azman A, Mohd Azami S, Mahfodz N, Bell-Sakyi L, Makepeace B, Abubakar S. Rickettsial agents from fleas infesting stray dogs and cats in rural and urban communities in Malaysia. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.1370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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3
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Teixeira RC, Baêta BA, Ferreira JS, Medeiros RC, Maya-Monteiro CM, Lara FA, Bell-Sakyi L, Fonseca AH. Fluorescent membrane markers elucidate the association of Borrelia burgdorferi with tick cell lines. ACTA ACUST UNITED AC 2017; 49:S0100-879X2016000700601. [PMID: 27332772 PMCID: PMC4918789 DOI: 10.1590/1414-431x20165211] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 03/28/2016] [Indexed: 11/23/2022]
Abstract
This study aimed to describe the association of Borrelia burgdorferi
s.s. with ixodid tick cell lines by flow cytometry and fluorescence and confocal
microscopy. Spirochetes were stained with a fluorescent membrane marker (PKH67 or
PKH26), inoculated into 8 different tick cell lines and incubated at 30°C for 24 h.
PKH efficiently stained B. burgdorferi without affecting bacterial
viability or motility. Among the tick cell lines tested, the Rhipicephalus
appendiculatus cell line RA243 achieved the highest percentage of
association/internalization, with both high (90%) and low (10%) concentrations of
BSK-H medium in tick cell culture medium. Treatment with cytochalasin D dramatically
reduced the average percentage of cells with internalized spirochetes, which passed
through a dramatic morphological change during their internalization by the host cell
as observed in time-lapse photography. Almost all of the fluorescent bacteria were
seen to be inside the tick cells. PKH labeling of borreliae proved to be a reliable
and valuable tool to analyze the association of spirochetes with host cells by flow
cytometry, confocal and fluorescence microscopy.
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Affiliation(s)
- R C Teixeira
- Universidade Federal Rural do Rio de Janeiro, Universidade Federal Rural do Rio de Janeiro, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Seropédica, RJ , Brasil, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brasil
| | - B A Baêta
- Universidade Federal Rural do Rio de Janeiro, Universidade Federal Rural do Rio de Janeiro, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Seropédica, RJ , Brasil, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brasil
| | - J S Ferreira
- Fundação Oswaldo Cruz, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, RJ , Brasil, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | - R C Medeiros
- Fundação Oswaldo Cruz, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, RJ , Brasil, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | - C M Maya-Monteiro
- Fundação Oswaldo Cruz, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, RJ , Brasil, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | - F A Lara
- Fundação Oswaldo Cruz, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, RJ , Brasil, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brasil
| | - L Bell-Sakyi
- The Pirbright Institute, The Pirbright Institute, The Tick Cell Biobank, Pirbright , UK, The Tick Cell Biobank, The Pirbright Institute, Pirbright, UK
| | - A H Fonseca
- Universidade Federal Rural do Rio de Janeiro, Universidade Federal Rural do Rio de Janeiro, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Seropédica, RJ , Brasil, Laboratório de Doenças Parasitárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brasil
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4
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Tuppurainen ESM, Venter EH, Coetzer JAW, Bell-Sakyi L. Lumpy skin disease: attempted propagation in tick cell lines and presence of viral DNA in field ticks collected from naturally-infected cattle. Ticks Tick Borne Dis 2014; 6:134-40. [PMID: 25468765 PMCID: PMC4329317 DOI: 10.1016/j.ttbdis.2014.11.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/20/2014] [Accepted: 11/03/2014] [Indexed: 11/19/2022]
Abstract
Lumpy skin disease (LSD) is of substantial economic importance for the cattle industry in Africa and the Near and Middle East. Several insect species are thought to transmit the disease mechanically. Recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (LSDV). The aim of this study was to attempt in vitro growth of the virus in Rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus in ticks collected from cattle during LSD outbreaks in Egypt and South Africa. No evidence was obtained for replication of LSDV in tick cell lines although the virus was remarkably stable, remaining viable for 35 days at 28 °C in tick cell cultures, in growth medium used for tick cells and in phosphate buffered saline. Viral DNA was detected in two-thirds of the 56 field ticks, making this the first report of the presence of potentially virulent LSDV in ticks collected from naturally infected animals.
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Affiliation(s)
- E S M Tuppurainen
- The Pirbright Institute, Ash Road, Pirbright, Surrey GU24 0NF, United Kingdom.
| | - E H Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - J A W Coetzer
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - L Bell-Sakyi
- The Pirbright Institute, Ash Road, Pirbright, Surrey GU24 0NF, United Kingdom
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5
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Postigo M, Taoufik A, Bell-Sakyi L, Bekker C, de Vries E, Morrison W, Jongejan F. Host cell-specific protein expression in vitro in Ehrlichia ruminantium. Vet Microbiol 2008; 128:136-47. [DOI: 10.1016/j.vetmic.2007.09.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 09/21/2007] [Accepted: 09/26/2007] [Indexed: 10/22/2022]
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6
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Postigo M, Taoufik A, Bell-Sakyi L, de Vries E, Morrison WI, Jongejan F. Differential transcription of the major antigenic protein 1 multigene family of Ehrlichia ruminantium in Amblyomma variegatum ticks. Vet Microbiol 2007; 122:298-305. [PMID: 17321077 DOI: 10.1016/j.vetmic.2007.01.019] [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] [Received: 08/18/2006] [Revised: 01/21/2007] [Accepted: 01/23/2007] [Indexed: 10/23/2022]
Abstract
The rickettsial pathogen Ehrlichia ruminantium causes heartwater in ruminants and is transmitted by ticks of the genus Amblyomma. The map1 gene, encoding the major surface protein MAP1, is a member of a multigene family containing 16 paralogs. In order to investigate differential transcription of genes of the map1 multigene family in vivo in unfed and feeding ticks, RNA was extracted from midguts and salivary glands of E. ruminantium-infected adult female Amblyomma variegatum ticks and analysed by RT-PCR using MAP1 paralog-specific primers. In unfed ticks, only transcripts from the map1-1 gene were observed in midguts and no transcripts were detected in salivary glands. In feeding ticks, map1-1 transcripts were more abundant in midguts whereas high levels of map1 transcripts were observed in salivary glands. Our results show that differential transcription of genes of the E. ruminantium map1 cluster occurs in vivo in different tissues of infected ticks before and during transmission feeding, indicating that this multigene family may be involved in functions of biological relevance in different stages of the life cycle of E. ruminantium.
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Affiliation(s)
- M Postigo
- Utrecht Centre for Tick-borne Diseases, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
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7
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Zweygarth E, Josemans AI, Spickett AM, Steyn HC, Putterill J, Troskie PC, Mtshali MS, Bell-Sakyi L, Shkap V, Fish L, Kocan KM, Blouin EF. In vitro cultivation of a south African isolate of an Anaplasma sp. in tick cell cultures. Onderstepoort J Vet Res 2006; 73:251-5. [PMID: 17283724] [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: 05/13/2023] Open
Abstract
This paper describes the first successful in vitro cultivation of a South African isolate of an Anaplasma sp., initially thought to be Anaplasma marginale, in the continuous tick cell line IDE8. Blood from a bovine naturally infected with A. marginale kept on the farm Kaalplaas (28 degrees 08' E, 25 degrees 38' S) was collected, frozen, thawed and used as inoculum on confluent IDE8 cell cultures. Twenty days after culture initiation small intracellular colonies were detected in a Cytospin smear prepared from culture supernatant. Cultures were passaged on Day 34. Attempts to infect IRE/CTVM18 cell cultures with the Kaalplaas isolate derived from IDE8 cultures failed, whereas a reference stock of A. marginale from Israel infected IRE/CTVM18 tick cell cultures. Attempts to infect various mammalian cell lines (BA 886, SBE 189, Vero, L 929, MDBK) and bovine erythrocytes, kept under various atmospheric conditions, with tick cell-derived Anaplasma sp. or the Israeli strain of A. marginale failed. Molecular characterization revealed that the blood inoculum used to initiate the culture contained both A. marginale and Anaplasma sp. (Omatienne) whereas the organisms from established cultures were only Anaplasma sp. (Omatjenne).
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Affiliation(s)
- E Zweygarth
- Onderstepoort Veterinary Institute, Private Bag X5, Onderstepoort 0110, South Africa.
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8
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Bell-Sakyi L, Koney EBM, Dogbey O, Walker AR. Incidence and prevalence of tick-borne haemoparasites in domestic ruminants in Ghana. Vet Parasitol 2005; 124:25-42. [PMID: 15350659 DOI: 10.1016/j.vetpar.2004.05.027] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [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: 02/26/2004] [Accepted: 05/13/2004] [Indexed: 11/22/2022]
Abstract
Giemsa-stained thin blood smears prepared monthly from cattle, sheep and goats in the Greater Accra region of Ghana between May 1994 and December 1996 were examined for presence of tick-borne haemoparasites. The majority of animals were less than 2 months old at the start of the survey. Monthly and cumulative incidences are presented of Anaplasma sp., Babesia bigemina, Borrelia sp., Eperythrozoon sp., Theileria mutans and Theileria velifera in cattle, Anaplasma sp., Borrelia sp., and Theileria sp. in sheep, and Anaplasma sp. in goats. T. mutans was the commonest parasite in cattle, with 100% incidence in calves by 10 months of age, and Anaplasma was commonest in small ruminants. The relative prevalence of these haemoparasites in blood smears from cattle, sheep and goats sampled on a single occasion at sites in all 10 regions of Ghana was found to be similar, though actual infection rates were lower. Packed cell volume (PCV) measurements from the sampled animals are also presented; no seasonal trends were evident in the PCV of the cattle, sheep and goats sampled monthly. In animals sampled on a single occasion, mean PCV was significantly higher in cattle and sheep without detectable haemoparasite infection, and in cattle was lowest in animals positive for both Babesia and Anaplasma, while there was no difference in mean PCV levels between parasitised and non-parasitised goats.
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Affiliation(s)
- L Bell-Sakyi
- Accra Veterinary Laboratory, Veterinary Services Department, Ministry of Food and Agriculture, PO Box M161, Accra, Ghana.
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9
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Abstract
Continuous cell lines from the ticks Amblyomma variegatum, Boophilus decoloratus, Boophilus microplus, Hyalomma anatolicum anatolicum, Ixodes scapularis, Ixodes ricinus and Rhipicephalus appendiculatus were tested for ability to support growth of the rickettsial pathogen Ehrlichia (previously Cowdria) ruminantium. Five E.ruminantium isolates, from West Africa, South Africa and the French West Indies, were used. Twelve tick cell lines were inoculated with E.ruminantium derived either from cultures of a bovine endothelial cell strain designated BPC or from other tick cell lines. Successful infection resulted in either continuous growth (in which the pathogen/cell line system could be perpetuated through regular subculture on fresh, uninfected cells for many months or years) or finite growth (in which the pathogen disappeared after one or a few subcultures). Infection with E.ruminantium from BPC was established in I.scapularis, I.ricinus and A.variegatum cell lines; E.ruminantium was transferred from these infected cell lines to B.decoloratus, B.microplus and R. appendiculatus cell lines. H.a.anatolicum cells could not be infected with E.ruminantium by any procedure. All five E.ruminantium isolates grew continuously in at least one tick cell line at temperatures between 28 degrees C and 37 degrees C; three of the isolates were successfully re-established in BPC following prolonged maintenance in tick cells. This study demonstrates that E.ruminantium is not intrinsically restricted to growth in cells from ticks of the natural vector genus Amblyomma.
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Affiliation(s)
- L Bell-Sakyi
- Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, Scotland, UK
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10
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Koney EBM, Dogbey O, Walker AR, Bell-Sakyi L. Ehrlichia ruminantium seroprevalence in domestic ruminants in Ghana. II. Point prevalence survey. Vet Microbiol 2004; 103:183-93. [PMID: 15504589 DOI: 10.1016/j.vetmic.2004.02.017] [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: 08/15/2003] [Revised: 02/03/2004] [Accepted: 02/13/2004] [Indexed: 11/29/2022]
Abstract
Serum samples collected on a single occasion from cattle, sheep and goats at sites in all 10 regions of Ghana were tested for antibodies to Ehrlichia (previously Cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive ELISA (PC-ELISA). The survey revealed the presence of heartwater-exposed ruminants throughout the country, with local seroprevalence up to 100%. Seronegative, and therefore presumably susceptible, animals were also present in all regions, in some areas in numbers high enough to indicate local endemic instability. Overall seroprevalences in cattle, sheep and goats were 61, 51 and 28% respectively, and were generally higher in the northern part of the country and lower in the forest zone. Amongst animals over 1 year old, two thirds of cattle and sheep, and around one third of goats throughout the country had been exposed to E. ruminantium. In the north, seroprevalence in sheep sampled with and without cattle was similar, whereas in the south seroconversion rates in sheep were significantly higher in areas where cattle were present.
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Affiliation(s)
- E B M Koney
- Veterinary Services Department, Ministry of Food and Agriculture, P.O. Box M161, Accra, Ghana
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11
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Lawrie CH, Uzcátegui NY, Armesto M, Bell-Sakyi L, Gould EA. Susceptibility of mosquito and tick cell lines to infection with various flaviviruses. Med Vet Entomol 2004; 18:268-274. [PMID: 15347394 DOI: 10.1111/j.0269-283x.2004.00505.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [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
The genus Flavivirus consists of more than 70 virus species and subtypes, the majority of which are transmitted by mosquitoes or ticks, although some have no known vector (NKV). The ability of these viruses to infect cultured cells derived from mosquito or tick species offers a useful insight into the suitability of such vectors to harbour and replicate particular viruses. We undertook a comparative study of the susceptibility of mammalian Vero cells, a clonal mosquito cell line (C6/36) and recently developed cell lines derived from the ticks (Acari: Ixodidae) Ixodes ricinus (L.) (IRE/CTVM18), I. scapularis (Say) (ISE6), Rhipicephalus appendiculatus (Neumann) (RAE/CTVM1) and Amblyomma variegatum (Fabricius) (AVL/CTVM17) to infection with 13 flaviviruses (and one alphavirus) using immunofluorescence microscopy and plaque assay techniques. The C6/36 mosquito cell line was infected by all the mosquito-borne flaviviruses tested but not by NKV viruses or tick-borne viruses, with the exception of Langat virus (LGTV). The tick cell lines were susceptible to infection by all of the tick-borne viruses tested, as well as two mosquito-borne viruses, West Nile virus (WNV) and the alphavirus, Venezuelan equine encephalitis virus (VEEV), but not other mosquito-borne viruses or NKV viruses.
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Affiliation(s)
- C H Lawrie
- Nuffield Department of Clinical Laboratory Sciences, University of Oxford, UK.
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12
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Bell-Sakyi L, Koney EBM, Dogbey O, Walker AR. Ehrlichia ruminantium seroprevalence in domestic ruminants in Ghana; I. Longitudinal survey in the Greater Accra Region. Vet Microbiol 2004; 100:175-88. [PMID: 15145496 DOI: 10.1016/j.vetmic.2004.02.010] [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: 08/15/2003] [Revised: 02/03/2004] [Accepted: 02/13/2004] [Indexed: 10/26/2022]
Abstract
Serum samples collected monthly over a 34-month period from cattle, sheep and goats in the Greater Accra Region of Ghana were tested for antibodies to Ehrlichia (previously Cowdria) ruminantium, the causative agent of heartwater, by polyclonal competitive ELISA (PC-ELISA). Maternal antibodies, detected in about half of animals followed from under 1 month old, declined to negative levels within 2-4 months. Amblyomma variegatum tick vectors were present on livestock in rural areas throughout the year, and first seroconversion occurred at any age, although the majority of calves seroconverted between 1 and 10 months old, sheep by 11 months, and goats by 7 months. All the cattle in the study became seropositive by 20 months of age, except one animal which subsequently died of heartwater. Following seroconversion, 25% of bovine sera tested negative in the PC-ELISA. Just over half the sheep in the survey seroconverted before or during the study period; following seroconversion, less than 3% of ovine sera became PC-ELISA negative. About a quarter of the goats seroconverted, and 34% of their post-seroconversion sera tested negative in the PC-ELISA. Overall, the serology indicated that virtually all cattle on the survey farms were exposed to E. ruminantium without suffering disease, but that a substantial proportion of sheep and goats escaped exposure and thus formed a susceptible population. E. ruminantium was detected in brains of 14, 36 and 4% of cattle, sheep and goats submitted for post mortem at the Accra Veterinary Laboratory, indicating that sheep were most at risk from heartwater disease.
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Affiliation(s)
- L Bell-Sakyi
- Veterinary Services Department, Ministry of Food and Agriculture, P. O. Box M161, Accra, Ghana.
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13
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Bell-Sakyi L, Koney E, Dogbey O, Walker A. Erratum to “Ehrlichia ruminatium seroprevalence in domestic ruminants in Ghana I. Longitudinal survey in the Greater Accra Region”. Vet Microbiol 2004. [DOI: 10.1016/j.vetmic.2004.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Abstract
The tick-borne rickettsia Cowdria ruminantium has been propagated continuously for over 500 days in the Ixodes scapularis tick cell line IDE8 by using the Gardel isolate from bovine endothelial cells as an inoculum. Infection of the tick cells was confirmed by PCR, karyotyping, electron microscopy, and reinfection of bovine cells.
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Affiliation(s)
- L Bell-Sakyi
- Centre for Tropical Veterinary Medicine, University of Edinburgh, Edinburgh, Scotland, United Kingdom.
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15
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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16
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Preston PM, Jackson LA, Sutherland IA, Bell-Sakyi L, Wilkie G, Brown DJ, Schofield J, Melrose TR, Sanderson A, Brown CG. Theileria annulata: the expression of two novel macroschizont antigens on the surface of infected mononuclear cells differs during in vitro attenuation of a virulent cell line. Exp Parasitol 1998; 89:228-40. [PMID: 9635447 DOI: 10.1006/expr.1998.4292] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [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: 11/22/2022]
Abstract
The first part of this study of the biological mechanisms underlying attenuation of virulent Theileria annulata macroschizont-infected cell lines screened four pairs of T. annulata (Hisar) in vivo- and in vitro-derived macroschizont-infected cell lines (lines) and identified a single in vivo-derived line, which induced lethal tropical theileriosis. The other seven lines were relatively avirulent. Analysis of the clinical, hematological, and parasitological responses of cattle immunized with different passages of the virulent line after in vitro culture showed that it was partly attenuated by passage (p) 50 and avirulent by p130. Clones representing the three glucose phosphate isomerase (GPI) isotypes, which constituted the newly isolated virulent culture, were obtained from p3 by limiting dilution; p50 and p130 consisted of one isotype. The second part of the study raised monoclonal antibodies (MAbs) against macroschizont-infected cells, as reagents for detecting antigenic differences between virulent and avirulent parasites, and identified two MAbs that recognized the surface of infected cells as well as macroschizonts. MAb EU1 recognized an antigen expressed by all the lines tested, whether in vitro- or in vivo-derived, whether uncloned or cloned, and irrespective of extent of subpassage in culture. MAb EU106 recognized an antigen whose expression by the virulent line and its clones disappeared on passage in culture. This antigen was not expressed at all by the avirulent in vitro-derived line prepared with cells from the same calf. Both antigens were expressed by lines infected with other stocks of T. annulata, including two lines known to induce lethal disease. The different profiles of expression of the two novel antigens, recognized by MAbs EU1 and EU106, by the line undergoing attenuation suggest (1) that the two antigens interact differently with the bovine immune system; and (2) that there are two, very different, potential roles for these antibodies in the development of vaccines against T. annulata infections.
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Affiliation(s)
- P M Preston
- Division of Biological Sciences, Institute of Cell, Animal and Population Biology, University of Edinburgh, Scotland
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17
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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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18
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Preston PM, Visser A, Abraham A, Richardson W, Richardson J, Forsyth L, Bell-Sakyi L, Wilkie G, Entrican G, Boid R, Spooner RL, Brown CG. Protective immune responses to Theileria annulata of relevance to vaccine development. Trop Anim Health Prod 1997; 29:136S-138S. [PMID: 9512761 DOI: 10.1007/bf02632954] [Citation(s) in RCA: 4] [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: 02/06/2023]
Abstract
A series of projects on Theileria annulata funded by the European Union (STD1/STD2/STD3) have provided convincing evidence that macrophage and natural killer (NK) cell-dependent immune mechanisms may directly control the proliferation of different stages of T. annulata in cattle. The evidence for this conclusion and the implications for vaccine development are discussed in the following paper.
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Affiliation(s)
- P M Preston
- Division of Biological Sciences, University of Edinburgh, Scotland, U.K
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19
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Abstract
Heartwater, an often fatal rickettsial disease of domestic ruminants transmitted by Amblyomma variegatum ticks, ranks with the A. variegatum-associated skin disease dermatophilosis as a major constraint to the upgrading of livestock productivity in Ghana. An epidemiological survey, using new diagnostic tests, is being carried out to determine the incidence and distribution of heartwater and other tickborne diseases in Ghanaian cattle, sheep and goats. Preliminary results from a longitudinal survey being carried out at sites in the Greater Accra Region indicating that although the vector ticks and the disease agent are widespread outside urban areas, not all animals are being exposed to heartwater during the first few months of life when an inverse age related resistance allows development of immunity without clinical disease. Thus a susceptible sub-population, at risk from heartwater, can exist even in areas of high tick challenge. The significance of these results for present and future tick and disease control strategies is discussed.
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Affiliation(s)
- L Bell-Sakyi
- Veterinary Services Department, Ministry of Agriculture, Accra, Ghana
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20
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Knight P, Musoke AJ, Gachanja JN, Nene V, Katzer F, Boulter N, Hall R, Brown CG, Williamson S, Kirvar E, Bell-Sakyi L, Hussain K, Tait A. Conservation of neutralizing determinants between the sporozoite surface antigens of Theileria annulata and Theileria parva. Exp Parasitol 1996; 82:229-41. [PMID: 8631374 DOI: 10.1006/expr.1996.0030] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [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: 02/01/2023]
Abstract
The sporozoite surface antigens SPAG-1 of Theileria annulata and p67 of Theileria parva are postulated to contain determinants necessary for host cell invasion and/or recognition and are both being considered as candidates for inclusion in subunit vaccines. Preliminary data suggest that these are related molecules. In this paper we describe the investigation of the relationship between these sporozoite antigens further by analysis of the immunological cross-reactivity using Mabs and sera raised against each antigen. The cross-reactions were examined by carrying out Western blots, IFA tests, and in vitro sporozoite neutralization assays. In addition, sequence comparison data which clearly establish that these surface antigens are encoded by related genes are presented. The regions of SPAG-1 identified as containing cross-reactive epitopes recognized by p67 antiserum correlated to regions of high predicted homology between p67 and SPAG-1, which are located at their respective N- and C-termini. Furthermore, p67 and SPAG-1 were found to contain cross-reactive determinants responsible for neutralization of sporozoite infectivity in vitro, and at least some of these were located in the C-termini of both molecules. The relevance of these findings to the possible roles for these molecules in host cell invasion is discussed.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/immunology
- Antigens, Protozoan/chemistry
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Antigens, Surface/chemistry
- Antigens, Surface/genetics
- Antigens, Surface/immunology
- Base Sequence
- Blotting, Western/veterinary
- Cattle
- Cross Reactions
- DNA, Protozoan/chemistry
- Epitope Mapping/veterinary
- Epitopes/chemistry
- Epitopes/genetics
- Epitopes/immunology
- Fluorescent Antibody Technique, Indirect/veterinary
- Immune Sera/immunology
- Molecular Sequence Data
- Neutralization Tests/veterinary
- Protozoan Proteins/chemistry
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Protozoan Vaccines
- Recombinant Proteins/immunology
- Sequence Homology, Amino Acid
- Software
- Theileria annulata/immunology
- Theileria parva/immunology
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Affiliation(s)
- P Knight
- Department of Veterinary Parasitology, University of Glasgow, UK
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21
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Boulter NR, Glass EJ, Knight PA, Bell-Sakyi L, Brown CG, Hall R. Theileria annulata sporozoite antigen fused to hepatitis B core antigen used in a vaccination trial. Vaccine 1995; 13:1152-60. [PMID: 8578798 DOI: 10.1016/0264-410x(95)00026-w] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [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: 01/31/2023]
Abstract
A C terminal fragment (SR1) of SPAG-1, a sporozoite surface antigen of Theileria annulata, has been expressed as a fusion protein in the e1 loop of hepatitis B core antigen (HBcAg). This recombinant antigen (HBcAg-SR1) is produced in the form of self-assembling polyhedral particles which have been visualised under the electron microscope. Cattle immunised with HBcAg-SR1 produced high titres of neutralising antibodies. A significant T cell response to both the HBcAg and SR1 determinants was observed but evidence of a T suppressor determinant in SR1 was also revealed. Immunised cattle showed some evidence of protection to sporozoite challenge as assessed by severity of the disease. The significance of these findings for the development of a sub-unit vaccine against T. annulata is discussed.
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Affiliation(s)
- N R Boulter
- Department of Biology, University of York, UK
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22
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Preston PM, Brown CG, Bell-Sakyi L, Richardson W, Sanderson A. Tropical theileriosis in Bos taurus and Bos taurus cross Bos indicus calves: response to infection with graded doses of sporozoites of Theileria annulata. Res Vet Sci 1992; 53:230-43. [PMID: 1439213 DOI: 10.1016/0034-5288(92)90115-i] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.7] [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: 12/27/2022]
Abstract
This work extends basic knowledge of tropical theileriosis in taurine and crossbred cattle. Infection of Bos taurus and Bos taurus cross Bos indicus (Sahiwal) calves with graded doses of sporozoites of Theileria annulata (Hissar), an Indian stock of the parasite, showed the following to be dose dependent in both cattle types: the time to appearance and population size of macroschizonts, microschizonts and piroplasms, time and severity of pyrexia, anaemia manifested by erythrocyte counts and haematocrit. All infections were accompanied by a prompt and severe panleucopenia. This effect was dose related in both the taurine and the Sahiwal crossbred calves. Lymphocyte counts returned to preinfection levels in the blood of animals which recovered, but death from theileriosis was characteristically accompanied by a persistent and severe lymphocytopenia. Flow cytometry using monoclonal antibodies to bovine mononuclear cells was used to identify the lymphocyte subsets involved in lymphocytopenia. The outcome of infection was dose dependent in the crossbred calves but not in taurine calves. Although the results obtained did not differ qualitatively between the two cattle types, they provided some preliminary evidence for resistance to tropical theileriosis in Sahiwal crossbred calves.
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Affiliation(s)
- P M Preston
- Division of Biological Sciences, Ashworth Laboratories, University of Edinburgh
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23
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Kachani M, Spooner RL, Rae P, Bell-Sakyi L, Brown CG. Stage-specific responses following infection with Theileria annulata as evaluated using ELISA. Parasitol Res 1992; 78:43-7. [PMID: 1584746 DOI: 10.1007/bf00936180] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [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: 12/27/2022]
Abstract
An enzyme-linked immunosorbent assay (ELISA) using sporozoite, schizont and piroplasm antigens was developed to study the immune response of animals that had been immunised with either Theileria annulata sporozoites or schizont-infected cells and then challenged with sporozoites. The aim was to identify the most suitable antigen for a routine screening test and to compare the sensitivity of the latter with that of the indirect fluorescent antibody test (IFAT). As determined by ELISA, cattle produced antibodies to all three antigens, regardless of the method of immunisation. The schizont antigen was the least sensitive, whereas the sporozoite antigen displayed high pre-inoculation values. In contrast, the piroplasm antigen exhibited low non-specific pre-infection levels and high post-immunisation and post-challenge values according to both ELISA and IFAT. Therefore, the latter was though to be the most appropriate antigen for use in ELISA.
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Affiliation(s)
- M Kachani
- Département de Parasitologie, Institut Agronomique et Vétérinaire Hassan II, Rabat Instituts, Morocco
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24
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Bell-Sakyi L. Continuous cell lines from the tick Hyalomma anatolicum anatolicum. J Parasitol 1991; 77:1006-8. [PMID: 1779279] [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: 12/28/2022] Open
Abstract
The establishment of 5 continuous cell lines from embryonic tissues of the tick Hyalomma anatolicum anatolicum is reported. Each line comprises 2 or more cell types; they are maintained at 28 C and 32 C in L-15/H-Lac medium with 20% fetal calf serum, and have been cryopreserved successfully. Sustained and consistent growth was achieved only after 12-41 mo in culture.
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Affiliation(s)
- L Bell-Sakyi
- Centre for Tropical Veterinary Medicine, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, Midlothian, United Kingdom
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25
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26
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Abstract
Serological evidence of infection with Babesia bovis and Babesia bigemina at a number of sites in Pemba was obtained using an enzyme-linked immunosorbent assay (ELISA) capable of detecting the appropriate parasite-specific antibody. Overall, 96% of animals were found to be positive for B. bovis, 88% were positive for B. bigemina and 88% were positive for both Babesia species. Antibody to B. bovis and B. bigemina was detected early in life in a number of calves born on Pemba, and was considered to be of maternal origin. The amount of maternal antibody in the serum of individual animals fell throughout the first 3 months of life. Later in life, antibody levels increased, probably in response to Babesia infection from natural tick challenge. These results suggest that infection with both Babesia parasites is widespread throughout Pemba and that both parasites probably exist in an enzootically stable situation.
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Affiliation(s)
- J D Woodford
- Smallholder Livestock Development, Pemba, Tanzania
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27
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Hadrill DJ, Boid R, Jones TW, Bell-Sakyi L. Bovine babesiosis on Nevis--implications for tick control. Vet Rec 1990; 126:403-4. [PMID: 2368265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- D J Hadrill
- Veterinary Services, Department of Agriculture, Charlestown, Nevis, West Indies
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