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Du C, Chen L, Liu G, Yuan F, Zhang Z, Rong M, Mo G, Liu C. Tick-Derived Peptide Blocks Potassium Channel TREK-1. Int J Mol Sci 2024; 25:8377. [PMID: 39125945 PMCID: PMC11312834 DOI: 10.3390/ijms25158377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Revised: 07/27/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
Ticks transmit a variety of pathogens, including rickettsia and viruses, when they feed on blood, afflicting humans and other animals. Bioactive components acting on inflammation, coagulation, and the immune system were reported to facilitate ticks' ability to suck blood and transmit tick-borne diseases. In this study, a novel peptide, IstTx, from an Ixodes scapularis cDNA library was analyzed. The peptide IstTx, obtained by recombinant expression and purification, selectively inhibited a potassium channel, TREK-1, in a dose-dependent manner, with an IC50 of 23.46 ± 0.22 μM. The peptide IstTx exhibited different characteristics from fluoxetine, and the possible interaction of the peptide IstTx binding to the channel was explored by molecular docking. Notably, extracellular acidification raised its inhibitory efficacy on the TREK-1 channel. Our results found that the tick-derived peptide IstTx blocked the TREK-1 channel and provided a novel tool acting on the potassium channel.
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Affiliation(s)
- Canwei Du
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Linyan Chen
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Guohao Liu
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Fuchu Yuan
- National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410006, China
| | - Zheyang Zhang
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Mingqiang Rong
- National & Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha 410006, China
- Frontiers Medical Center, Tianfu Jincheng Laboratory, No. 387-201 Heming Street, Chengdu 610212, China
| | - Guoxiang Mo
- College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Changjun Liu
- School of Life and Health Sciences, Hunan University of Science and Technology, Xiangtan 411201, China
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Schroers M, Meyer-Lindenberg A. Performance and overview of clinically relevant areas of application of saliva testing in the cat. Front Vet Sci 2024; 11:1385345. [PMID: 38840640 PMCID: PMC11150842 DOI: 10.3389/fvets.2024.1385345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Accepted: 05/10/2024] [Indexed: 06/07/2024] Open
Abstract
Introduction The cat represents an important model in order to investigate basic physiological knowledge of salivary secretion as well as pharmacokinetics of active substances. Objective The aim of the study was to review in which diagnostic application areas saliva testing is routinely used and in which areas it could be further explored in the future. Materials and methods Literature relevant to the research question was collected in March 2022 using the Pubmed database. Results The diagnosis of infectious diseases in cat saliva is one of the most important fields of application. Saliva diagnostics may also indicate dental diseases, allergies or kidney and other metabolic diseases. Sexual and stress hormones can also be measured in cat saliva. A number of clinically relevant allergens in cat saliva that may cause allergies in humans has been investigated and described, in addition to infectious agents that can be transmitted from cats to humans. Conclusions Saliva testing in cats can be useful in many areas, including the detection of infectious diseases, allergies and dental disease. However, it is far from being used to its full potential within veterinary medicine.
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Affiliation(s)
- Maike Schroers
- Clinic of Small Animal Surgery and Reproduction, Veterinary Faculty, Ludwig-Maximilians-University Munich, Munich, Germany
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Da Lage JL, Fontenelle A, Filée J, Merle M, Béranger JM, Almeida CE, Folly Ramos E, Harry M. Evidence that hematophagous triatomine bugs may eat plants in the wild. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2024; 165:104059. [PMID: 38101706 DOI: 10.1016/j.ibmb.2023.104059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/29/2023] [Accepted: 12/07/2023] [Indexed: 12/17/2023]
Abstract
Blood feeding is a secondary adaptation in hematophagous bugs. Many proteins are secreted in the saliva that are devoted to coping with the host's defense and to process the blood meal. Digestive enzymes that are no longer required for a blood meal would be expected to be eventually lost. Yet, in many strictly hematophagous arthropods, α-amylase genes, which encode the enzymes that digest starch from plants, are still present and transcribed, including in the kissing bug Rhodnius prolixus (Hemiptera, Reduviidae) and its related species, which transmit the Chagas disease. We hypothesized that retaining α-amylase could be advantageous if the bugs occasionally consume plant tissues. We first checked that the α-amylase protein of Rhodnius robustus retains normal amylolytic activity. Then we surveyed hundreds of gut DNA extracts from the sylvatic R. robustus to detect traces of plants. We found plant DNA in 8% of the samples, mainly identified as Attalea palm trees, where R. robustus are usually found. We suggest that although of secondary importance in the blood-sucking bugs, α-amylase may be needed during occasional plant feeding and thus has been retained.
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Affiliation(s)
- Jean-Luc Da Lage
- Université Paris-Saclay, CNRS, IRD, UMR 9191 Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France.
| | - Alice Fontenelle
- Université Paris-Saclay, CNRS, IRD, UMR 9191 Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France
| | - Jonathan Filée
- Université Paris-Saclay, CNRS, IRD, UMR 9191 Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France
| | - Marie Merle
- Université Paris-Saclay, CNRS, IRD, UMR 9191 Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France
| | - Jean-Michel Béranger
- Département Systématique and Evolution, Muséum National d'Histoire Naturelle, Paris, France; IRD, AP-HM, SSA, VITROME, IHU-Méditerranée Infection, Aix Marseille Université, Marseille, France
| | - Carlos Eduardo Almeida
- Universidade Federal do Rio de Janeiro (UFRJ), Centro de Ciências da Saúde, Instituto de Biologia, Departamento de Zoologia, Rio de Janeiro, Brazil
| | - Elaine Folly Ramos
- Departamento de Engenharia e Meio Ambiente - DEMA, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - Myriam Harry
- Université Paris-Saclay, CNRS, IRD, UMR 9191 Évolution, Génomes, Comportement et Écologie, 91198, Gif-sur-Yvette, France
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Teo E, Russell H, Lambert T, Webster R, Yappa A, McDonagh P, Harper G, Barker D, Barker SC. The weather determines the number of cases of tick paralysis in dogs and cats in eastern Australia, caused by Ixodes holocyclus, the eastern paralysis tick. Aust Vet J 2023; 101:479-489. [PMID: 37772326 DOI: 10.1111/avj.13289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 08/28/2023] [Accepted: 09/10/2023] [Indexed: 09/30/2023]
Abstract
We studied over 222,000 cases of emergency veterinary consultations in four regions along the eastern coast of Australia. We found that cases of tick paralysis (TP) caused by the eastern paralysis tick, Ixodes holocyclus, accounted for 7.5% of these cases: >16,000 cases. The season of TP and the number (prevalence) of TP cases varied among regions and over the years. Our study of the association between weather and (i) the start of the season of TP, and (ii) the number of TP cases revealed much about the intricate relationship between the weather and I. holocyclus. We studied the effect of the hypothetical availability of isoxazoline-containing tick-preventative medicines and found that an increase in the availability of these medicines had significantly contributed to the decrease in TP cases. We found that the weather in winter accounted for the time of the year the season of TP starts whereas the weather in summer accounted for the number of TP cases in the TP season. Last, through a study of the effects of shifts in the climate under four hypothetical scenarios (warmer/cooler and drier/wetter than average), we propose that the start of the season of TP depends on how soon the weather in winter becomes suitable for the activity (e.g. host-seeking) and the development of I. holocyclus nymphs, and that the number of TP cases during the TP season depends on how many engorged female ticks and their eggs survive during summer.
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Affiliation(s)
- Ejm Teo
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Queensland, 4072, Australia
| | - H Russell
- Northside Emergency Veterinary Service, Terrey Hills, New South Wales, 2084, Australia
| | - T Lambert
- Northside Emergency Veterinary Service, Terrey Hills, New South Wales, 2084, Australia
| | - R Webster
- Animal Emergency Australia, Springwood, Queensland, 4127, Australia
| | - A Yappa
- Animal Emergency Australia, Springwood, Queensland, 4127, Australia
| | - P McDonagh
- Boehringer Ingelheim Animal Health Australia, Macquarie Park, New South Wales, 2113, Australia
| | - G Harper
- Boehringer Ingelheim Animal Health Australia, Macquarie Park, New South Wales, 2113, Australia
| | - D Barker
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, 4343, Australia
| | - S C Barker
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Queensland, 4072, Australia
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Holland CT. Static anisocoria in cats and dogs with naturally occurring tick paralysis (Ixodes holocyclus). Aust Vet J 2023; 101:383-390. [PMID: 37574813 DOI: 10.1111/avj.13276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 03/27/2023] [Accepted: 07/29/2023] [Indexed: 08/15/2023]
Abstract
OBJECTIVE To characterise the novel occurrence and neuro-ophthalmological features of static anisocoria in cats and dogs with tick paralysis (TP) (Ixodes holocyclus) due to a single tick located remote from the head and neck. DESIGN Observational case series with retrospective analysis. METHODS Medical records were reviewed from 69 cats and 169 dogs treated for TP from a suburban veterinary hospital in Newcastle, New South Whales, between September 2005 and October 2021. RESULTS Anisocoria was observed in 2/18 (11.1%) cats and 3/30 (10.0%) dogs with a single tick located remote from the head and neck. These proportions were not different when compared within species to 4 of 28 (14.3%) cats and 16 of 98 (16.3%) dogs with aniscocoria with a single tick located on the head and neck region (P = 1 and 0.56 respectively). Anisocoria arose from pupillary efferent dysfunction and included unilateral oculoparasympathetic dysfunction (internal ophthalmoplegia) in one dog, unilateral oculosympathetic dysfunction (Horner's syndrome) in one cat and one dog, and a combination of bilateral, but asymmetric, oculosympathetic and oculoparasympathetic dysfunction in one cat and one dog. CONCLUSION It is proposed that anisocoria in cases of TP with a tick located remote from the head and neck is due to an intrinsic latent asymmetry in the safety factor for pupillary efferent function that is unmasked by a systemically distributed holocyclotoxin inhibiting neural transmission within this system, and this is the prevailing pathomechanism, rather than a direct local effect, underscoring anisocoria with a tick located on the head or neck.
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Affiliation(s)
- C T Holland
- Merewether Veterinary Hospital, Merewether, New South Wales, Australia
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6
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Teo EJM, Arganda A, Webster R, Yappa A, Barker D, Barker SC. Two seasons of tick paralysis in Victoria yet one season in Queensland and New South Wales, Australia. Int J Parasitol 2023; 53:43-53. [PMID: 36462559 DOI: 10.1016/j.ijpara.2022.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 12/02/2022]
Abstract
We studied 22,840 cases of tick paralysis in dogs and cats that were attributable to infestation with the eastern paralysis tick, Ixodes holocyclus. We report that the mortality rates from the holocyclotoxins of the tick or from euthanasia due to complications arising from tick paralysis in dogs and cats were 10% and 8%, respectively. The distribution of cases of tick paralysis among the 52 weeks of 22 years (1999 to 2020, inclusive) in four regions along the eastern coast of Australia revealed much about how the life-cycle of this tick varied among regions. The four regions in our study were: (i) Cairns, Innisfail, and surrounding postcodes in Far North Queensland; (ii) South East Queensland; (iii) Northern Beaches of Sydney in New South Wales; and (iv) the Shire of East Gippsland in Victoria. We found that the season of tick paralysis started earlier in more northerly latitudes than in more southerly latitudes. We also found that Victoria has two seasons of tick paralysis, one from approximately the third week of February to the first week of May, and another from approximately the third week of September to the third week of December, whereas all of the other regions we studied in eastern Australia only had one season of tick paralysis. When we studied the two seasons of tick paralysis in Victoria, we found a statistically significant negative correlation between the number of cases of tick paralysis between the two seasons: the more cases in one season, the fewer the cases in the next season. One possible explanation for the negative correlation may be immunity to I. holocyclus acquired by dogs and cats in the first season.
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Affiliation(s)
- Ernest J M Teo
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Alexa Arganda
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Robert Webster
- Animal Emergency Australia, Springwood, QLD 4127, Australia
| | - Amanda Yappa
- Animal Emergency Australia, Springwood, QLD 4127, Australia
| | - Dayana Barker
- School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia
| | - Stephen C Barker
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia.
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Neuroimaging in Tick Paralysis: Looking Outside the Box. Infect Dis Rep 2022; 14:837-840. [PMID: 36412743 PMCID: PMC9680300 DOI: 10.3390/idr14060085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/09/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022] Open
Abstract
Tick paralysis is a rare but potentially deadly form of muscle paralysis caused by a neurotoxin transmitted through the saliva of gravid, engorged female ticks of various species. Often, there is an initial misdiagnosis or delay in diagnosis due to the rarity of the diagnosis, the obscure location of the tick, and the disease's clinical similarity to Guillain-Barre syndrome. We report the case of a 4-year-old girl with tick paralysis in whom the tick was not found until 2 days after hospital admission. Upon the review of the imaging, it was discovered that the tick was visible on the MRI of the brain that had been reported as normal.
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8
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Wu J, Zhou X, Chen Q, Chen Z, Zhang J, Yang L, Sun Y, Wang G, Dai J, Feng T. Defensins as a promising class of tick antimicrobial peptides: a scoping review. Infect Dis Poverty 2022; 11:71. [PMID: 35725522 PMCID: PMC9208123 DOI: 10.1186/s40249-022-00996-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 06/06/2022] [Indexed: 11/11/2022] Open
Abstract
Background Ticks are hematophagous parasites that transmit an extensive range of pathogens to their vertebrate hosts. Ticks can destroy invading microorganisms or alleviate infection via their rudimentary but orchestrated innate immune system. Antimicrobial peptides (AMPs) are important components of tick innate immunity. Among these humoral effector molecules, defensins are well-studied and widely identified in various species of Ixodidae (hard ticks) and Argasidae (soft ticks). This review was aimed at presenting the characterization of tick defensins from structure-based taxonomic status to antimicrobial function. Main text All published papers written in English from 2001 to May 2022 were searched through PubMed and Web of Science databases with the combination of relevant terms on tick defensins. Reports on identification and characterization of tick defensins were included. Of the 329 entries retrieved, 57 articles were finally eligible for our scoping review. Tick defensins mainly belong to the antibacterial ancient invertebrate-type defensins of the cis-defensins superfamily. They are generally small, cationic, and amphipathic, with six cysteine residues forming three intra-molecular disulfide bonds. Tick defensins primarily target membranes of a variety of pathogens, including Gram-positive and Gram-negative bacteria, fungi, viruses, and protozoa. Since tick defensins have a high degree of variability, we summarize their common biological properties and enumerate representative peptides. Along with the various and potent antimicrobial activities, the role of tick defensins in determining vector competence is discussed. Conclusions Due to their broad-spectrum antimicrobial activities, tick defensins are considered novel candidates or targets for controlling infectious diseases. Graphical Abstract ![]()
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Affiliation(s)
- Jiahui Wu
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Xia Zhou
- School of Biology and Basic Medical Science, Suzhou Medical College of Soochow University, Suzhou, China
| | - Qiaoqiao Chen
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Zhiqiang Chen
- Department of Nuclear Medicine, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jinyu Zhang
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Lele Yang
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Yuxuan Sun
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China
| | - Guohui Wang
- School of Life Science and Technology, Weifang Medical University, Weifang, China.
| | - Jianfeng Dai
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China.
| | - Tingting Feng
- Institute of Biology and Medical Sciences, Jiangsu Key Laboratory of Infection and Immunity, Soochow University, Suzhou, China.
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Lu XY, Zhang QF, Jiang DD, Du CH, Xu R, Guo XG, Yang X. Characterization of the complete mitochondrial genome of Ixodes granulatus (Ixodidae) and its phylogenetic implications. Parasitol Res 2022; 121:2347-2358. [PMID: 35650429 DOI: 10.1007/s00436-022-07561-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 05/23/2022] [Indexed: 11/25/2022]
Abstract
Ticks are deemed to be second only to mosquitoes as the most common vector of human infectious diseases worldwide that give rise to human and animal diseases and economic losses to livestock production. Our understanding of the phylogenetic analysis between tick lineages has been restricted by the phylogenetic markers of individual genes. Genomic data research could help advance our understanding of phylogenetic analysis and molecular evolution. Mitochondrial genomic DNA facilitated the phylogenetic analysis of eukaryotes containing ticks. In this study, we sequenced and assembled the circular complete mitogenome information of Ixodes granulatus. The 14,540-bp mitogenome consists of 37 genes, including 13 protein-coding genes (PCGs), two genes for ribosomal RNA (rRNAs), and 22 genes for transfer RNA (tRNAs), and the origin of the L-strand replication region. The directions of the coding strand and component genes in the non-Australasian Ixodes mitochondrial genome were similar to those found in most other Australasian Ixodes, except for the loss of a lengthy control region. The phylogenetic tree based on maximum likelihood (ML) and Bayesian inference (BI) computational algorithms showed that I. granulatus exhibits a close relationship with I. hexagonus and I. ricinus. To our knowledge, this is the first study exploring the complete mitogenome for the species I. granulatus. Our results provide new insights for further research on the evolution, population genetics, systematics, and molecular ecology of ticks.
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Affiliation(s)
- Xin-Yan Lu
- Integrated Laboratory of Pathogenic Biology, College of Preclinical Medicine, Dali University, Dali, 671000, People's Republic of China
| | - Quan-Fu Zhang
- Department of Gastroenterology, Clinical Medical College and the First Affiliated Hospital of Chengdu Medical College, Chengdu, China
| | - Dan-Dan Jiang
- School of Public Health, Dali University, Dali, 671000, People's Republic of China
| | - Chun-Hong Du
- Yunnan Institute of Endemic Diseases Control and Prevention, Dali, Yunnan, 671000, People's Republic of China
| | - Rong Xu
- College of Preclinical Medicine, Dali University, Dali, 671000, People's Republic of China
| | - Xian-Guo Guo
- Institute of Pathogens and Vectors, Yunnan Provincial Key Laboratory for Zoonosis Control and Prevention, Dali University, Dali, 671000, Yunnan, China.
| | - Xing Yang
- Integrated Laboratory of Pathogenic Biology, College of Preclinical Medicine, Dali University, Dali, 671000, People's Republic of China.
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Ali A, Zeb I, Alouffi A, Zahid H, Almutairi MM, Ayed Alshammari F, Alrouji M, Termignoni C, Vaz IDS, Tanaka T. Host Immune Responses to Salivary Components - A Critical Facet of Tick-Host Interactions. Front Cell Infect Microbiol 2022; 12:809052. [PMID: 35372098 PMCID: PMC8966233 DOI: 10.3389/fcimb.2022.809052] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 02/04/2022] [Indexed: 12/15/2022] Open
Abstract
Tick sialome is comprised of a rich cocktail of bioactive molecules that function as a tool to disarm host immunity, assist blood-feeding, and play a vibrant role in pathogen transmission. The adaptation of the tick's blood-feeding behavior has lead to the evolution of bioactive molecules in its saliva to assist them to overwhelm hosts' defense mechanisms. During a blood meal, a tick secretes different salivary molecules including vasodilators, platelet aggregation inhibitors, anticoagulants, anti-inflammatory proteins, and inhibitors of complement activation; the salivary repertoire changes to meet various needs such as tick attachment, feeding, and modulation or impairment of the local dynamic and vigorous host responses. For instance, the tick's salivary immunomodulatory and cement proteins facilitate the tick's attachment to the host to enhance prolonged blood-feeding and to modulate the host's innate and adaptive immune responses. Recent advances implemented in the field of "omics" have substantially assisted our understanding of host immune modulation and immune inhibition against the molecular dynamics of tick salivary molecules in a crosstalk between the tick-host interface. A deep understanding of the tick salivary molecules, their substantial roles in multifactorial immunological cascades, variations in secretion, and host immune responses against these molecules is necessary to control these parasites. In this article, we reviewed updated knowledge about the molecular mechanisms underlying host responses to diverse elements in tick saliva throughout tick invasion, as well as host defense strategies. In conclusion, understanding the mechanisms involved in the complex interactions between the tick salivary components and host responses is essential to decipher the host defense mechanisms against the tick evasion strategies at tick-host interface which is promising in the development of effective anti-tick vaccines and drug therapeutics.
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Affiliation(s)
- Abid Ali
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Ismail Zeb
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Abdulaziz Alouffi
- King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia
| | - Hafsa Zahid
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, Pakistan
| | - Mashal M. Almutairi
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Fahdah Ayed Alshammari
- College of Sciences and Literature Microbiology, Nothern Border University, Rafha, Saudi Arabia
| | - Mohammed Alrouji
- College of Applied Medical Sciences, Shaqra University, Shaqra, Saudi Arabia
| | - Carlos Termignoni
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Itabajara da Silva Vaz
- Centro de Biotecnologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Tetsuya Tanaka
- Laboratory of Infectious Diseases, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima, Japan
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11
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Rodriguez-Valle M, McAlister S, Moolhuijzen PM, Booth M, Agnew K, Ellenberger C, Knowles AG, Vanhoff K, Bellgard MI, Tabor AE. Immunomic Investigation of Holocyclotoxins to Produce the First Protective Anti-Venom Vaccine Against the Australian Paralysis Tick, Ixodes holocyclus. Front Immunol 2021; 12:744795. [PMID: 34671357 PMCID: PMC8522651 DOI: 10.3389/fimmu.2021.744795] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 09/15/2021] [Indexed: 12/20/2022] Open
Abstract
Venom producing animals are ubiquitously disseminated among vertebrates and invertebrates such as fish, snakes, scorpions, spiders, and ticks. Of the ~890 tick species worldwide, 27 have been confirmed to cause paralysis in mammalian hosts. The Australian paralysis tick (Ixodes holocyclus) is the most potent paralyzing tick species known. It is an indigenous three host tick species that secretes potent neurotoxins known as holocyclotoxins (HTs). Holocyclotoxins cause a severe and harmful toxicosis leading to a rapid flaccid paralysis which can result in death of susceptible hosts such as dogs. Antivenins are generally polyclonal antibody treatments developed in sheep, horses or camels to administer following bites from venomous creatures. Currently, the methods to prevent or treat tick paralysis relies upon chemical acaricide preventative treatments or prompt removal of all ticks attached to the host followed by the administration of a commercial tick-antiserum (TAS) respectively. However, these methods have several drawbacks such as poor efficacies, non-standardized dosages, adverse effects and are expensive to administer. Recently the I. holocyclus tick transcriptome from salivary glands and viscera reported a large family of 19 holocyclotoxins at 38-99% peptide sequence identities. A pilot trial demonstrated that correct folding of holocyclotoxins is needed to induce protection from paralysis. The immunogenicity of the holocyclotoxins were measured using commercial tick antiserum selecting HT2, HT4, HT8 and HT11 for inclusion into the novel cocktail vaccine. A further 4 HTs (HT1, HT12, HT14 and HT17) were added to the cocktail vaccine to ensure that the sequence variation among the HT protein family was encompassed in the formulation. A second trial comparing the cocktail of 8 HTs to a placebo group demonstrated complete protection from tick challenge. Here we report the first successful anti-venom vaccine protecting dogs from tick paralysis.
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Affiliation(s)
- Manuel Rodriguez-Valle
- Centre for Animal Science, The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, St. Lucia, QLD, Australia
| | - Sonia McAlister
- Centre for Animal Science, The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, St. Lucia, QLD, Australia
| | | | - Mitchell Booth
- Centre for Animal Science, The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, St. Lucia, QLD, Australia
| | - Kim Agnew
- Paul Dick & Associates Ltd, Castle Hill, NSW, Australia
| | - Claudia Ellenberger
- Elanco Animal Health, Yarrandoo Research and Development Centre, Kemps Creek, NSW, Australia
| | | | - Kathleen Vanhoff
- Elanco Animal Health, Yarrandoo Research and Development Centre, Kemps Creek, NSW, Australia
| | - Matthew I Bellgard
- eResearch Office, Queensland University of Technology, Brisbane, QLD, Australia
| | - Ala E Tabor
- Centre for Animal Science, The University of Queensland, Queensland Alliance for Agriculture & Food Innovation, St. Lucia, QLD, Australia.,School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, QLD, Australia
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12
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A Review of Australian Tick Vaccine Research. Vaccines (Basel) 2021; 9:vaccines9091030. [PMID: 34579266 PMCID: PMC8473225 DOI: 10.3390/vaccines9091030] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 09/06/2021] [Accepted: 09/08/2021] [Indexed: 11/17/2022] Open
Abstract
Tick vaccine research in Australia has demonstrated leadership worldwide through the development of the first anti-tick vaccine in the 1990s. Australia’s Commonwealth Scientific and Industrial Research Organisation’s (CSIRO) research led to the development of vaccines and/or precursors of vaccines (such as crude extracts) for both the cattle tick and the paralysis tick. CSIRO commercialised the Bm86 vaccine in the early 1990s for Rhipicephalus australis; however, issues with dosing and lack of global conservation led to the market closure of Tick-GARD in Australia. New research programs arose both locally and globally. The Australian paralysis tick Ixodes holocyclus has perplexed research veterinarians since the 1920s; however, not until the 2000s did biotechnology exist to elucidate the neurotoxin—holocyclotoxin family of toxins leading to a proof of concept vaccine cocktail. This review revisits these discoveries and describes tributes to deceased tick vaccine protagonists in Australia, including Sir Clunies Ross, Dr Bernard Stone and Dr David Kemp.
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13
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Reck J, Webster A, Dall'Agnol B, Pienaar R, de Castro MH, Featherston J, Mans BJ. Transcriptomic Analysis of Salivary Glands of Ornithodoros brasiliensis Aragão, 1923, the Agent of a Neotropical Tick-Toxicosis Syndrome in Humans. Front Physiol 2021; 12:725635. [PMID: 34421661 PMCID: PMC8378177 DOI: 10.3389/fphys.2021.725635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 07/12/2021] [Indexed: 12/04/2022] Open
Abstract
Tick salivary glands produce and secrete a variety of compounds that modulate host responses and ensure a successful blood meal. Despite great progress made in the identification of ticks salivary compounds in recent years, there is still a paucity of information concerning salivary molecules of Neotropical argasid ticks. Among this group of ticks, considering the number of human cases of parasitism, including severe syndromes and hospitalization, Ornithodoros brasiliensis can be considered one of the major Neotropical argasid species with impact in public health. Here, we describe the transcriptome analysis of O. brasiliensis salivary glands (ObSG). The transcriptome yielded ~14,957 putative contigs. A total of 368 contigs were attributed to secreted proteins (SP), which represent approximately 2.5% of transcripts but ~53% expression coverage transcripts per million. Lipocalins are the major protein family among the most expressed SP, accounting for ~16% of the secretory transcripts and 51% of secretory protein abundance. The most expressed transcript is an ortholog of TSGP4 (tick salivary gland protein 4), a lipocalin first identified in Ornithodoros kalahariensis that functions as a leukotriene C4 scavenger. A total of 55 lipocalin transcripts were identified in ObSG. Other transcripts potentially involved in tick-host interaction included as: basic/acid tail secretory proteins (second most abundant expressed group), serine protease inhibitors (including Kunitz inhibitors), 5' nucleotidases (tick apyrases), phospholipase A2, 7 disulfide bond domain, cystatins, and tick antimicrobial peptides. Another abundant group of proteins in ObSG is metalloproteases. Analysis of these major protein groups suggests that several duplication events after speciation were responsible for the abundance of redundant compounds in tick salivary glands. A full mitochondrial genome could be assembled from the transcriptome data and confirmed the close genetic identity of the tick strain sampled in the current study, to a tick strain previously implicated in tick toxicoses. This study provides novel information on the molecular composition of ObSG, a Brazilian endemic tick associated with several human cases of parasitism. These results could be helpful in the understanding of clinical findings observed in bitten patients, and also, could provide more information on the evolution of Neotropical argasids.
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Affiliation(s)
- Jose Reck
- Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Eldorado do Sul, Brazil
| | - Anelise Webster
- Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Eldorado do Sul, Brazil
| | - Bruno Dall'Agnol
- Instituto de Pesquisas Veterinárias Desidério Finamor (IPVDF), Eldorado do Sul, Brazil
| | - Ronel Pienaar
- Epidemiology, Parasites and Vectors, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa
| | - Minique H de Castro
- Agricultural Research Council, Biotechnology Platform, Pretoria, South Africa
| | | | - Ben J Mans
- Epidemiology, Parasites and Vectors, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria, South Africa.,Department of Veterinary Tropical Diseases, Vector and Vector-borne Disease Research Programme, University of Pretoria, Pretoria, South Africa.,Department of Life and Consumer Sciences, University of South Africa, Pretoria, South Africa
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14
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Liu Q, Deng Y, Song A, Xiang Y, Chen D, Wei L. Comparative analysis of mite genomes reveals positive selection for diet adaptation. Commun Biol 2021; 4:668. [PMID: 34083730 PMCID: PMC8175442 DOI: 10.1038/s42003-021-02173-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 04/30/2021] [Indexed: 02/06/2023] Open
Abstract
Diet is a powerful evolutionary force for species adaptation and diversification. Acari is one of the most abundant clades of Arachnida, exhibiting diverse dietary types, while the underlying genetic adaptive mechanisms are not fully understood. Based on comparative analyses of 15 Acari genomes, we found genetic bases for three specialized diets. Herbivores experienced stronger selection pressure than other groups; the olfactory genes and gene families involving metabolizing toxins showed strong adaptive signals. Genes and gene families related to anticoagulation, detoxification, and haemoglobin digestion were found to be under strong selection pressure or significantly expanded in the blood-feeding species. Lipid metabolism genes have a faster evolutionary rate and been subjected to greater selection pressures in fat-feeding species; one positively selected site in the fatty-acid amide hydrolases 2 gene was identified. Our research provides a new perspective for the evolution of Acari and offers potential target loci for novel pesticide development.
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Affiliation(s)
- Qiong Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yuhua Deng
- Clinical Research Institute, The First People's Hospital of Foshan, Foshan, China
| | - An Song
- ShaanXi JunDa Forensic Medicine Expertise Station, The Fourth Military Medical University, Xi'an, China
| | - Yifan Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - De Chen
- MOE Key Laboratory for Biodiversity Science and Ecological Engineering, College of Life Sciences, Beijing Normal University, Beijing, China.
| | - Lai Wei
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
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15
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Teo EJM, Vial MN, Hailu S, Kelava S, Zalucki MP, Furlong MJ, Barker D, Barker SC. Climatic requirements of the eastern paralysis tick, Ixodes holocyclus, with a consideration of its possible geographic range up to 2090. Int J Parasitol 2021; 51:241-249. [PMID: 33513402 DOI: 10.1016/j.ijpara.2020.08.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/18/2020] [Accepted: 08/26/2020] [Indexed: 11/24/2022]
Abstract
The eastern paralysis tick, Ixodes holocyclus, is an ectoparasite of medical and veterinary importance in Australia. The feeding of I. holocyclus is associated with an ascending flaccid paralysis which kills many dogs and cats each year, with the development of mammalian meat allergy in some humans, and with the transmission of Rickettsia australis (Australian scrub typhus) to humans. Although I. holocyclus has been well studied, it is still not known exactly why this tick cannot establish outside of its present geographic distribution. Here, we aim to account for the presence as well as the absence of I. holocyclus in regions of Australia. We modelled the climatic requirements of I. holocyclus with two methods, CLIMEX, and a new envelope-model approach which we name the 'climatic-range method'. These methods allowed us to account for 93% and 96% of the geographic distribution of I. holocyclus, respectively. Our analyses indicated that the geographic range of I. holocyclus may not only shift south towards Melbourne, but may also expand in the future, depending on which climate-change scenario comes to pass.
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Affiliation(s)
- Ernest J M Teo
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Melanie N Vial
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Semira Hailu
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Samuel Kelava
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Myron P Zalucki
- School of Biological Sciences, The University of Queensland, QLD 4072, Australia
| | - Michael J Furlong
- School of Biological Sciences, The University of Queensland, QLD 4072, Australia
| | - Dayana Barker
- School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia
| | - Stephen C Barker
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia.
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16
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De novo assembled salivary gland transcriptome and expression pattern analyses for Rhipicephalus evertsi evertsi Neuman, 1897 male and female ticks. Sci Rep 2021; 11:1642. [PMID: 33452281 PMCID: PMC7810686 DOI: 10.1038/s41598-020-80454-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/21/2020] [Indexed: 12/13/2022] Open
Abstract
Ticks secrete proteins in their saliva that change over the course of feeding to modulate the host inflammation, immune responses, haemostasis or may cause paralysis. RNA next generation sequencing technologies can reveal the complex dynamics of tick salivary glands as generated from various tick life stages and/or males and females. The current study represents 15,115 Illumina sequenced contigs of the salivary gland transcriptome from male and female Rhipicephalus evertsi evertsi ticks of early, mid and late feeding stages from 1320 separate assemblies using three short read assemblers. The housekeeping functional class contributed to the majority of the composition of the transcriptome (80%) but with lower expression (51%), while the secretory protein functional class represented only 14% of the transcriptome but 46% of the total coverage. Six percent had an unknown status contributing 3% of the overall expression in the salivary glands. Platelet aggregation inhibitors, blood clotting inhibitors and immune-modulators orthologous to the ancestral tick lineages were confirmed in the transcriptome and their differential expression during feeding in both genders observed. This transcriptome contributes data of importance to salivary gland biology and blood feeding physiology of non-model organisms.
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17
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Martins LA, Bensaoud C, Kotál J, Chmelař J, Kotsyfakis M. Tick salivary gland transcriptomics and proteomics. Parasite Immunol 2020; 43:e12807. [PMID: 33135186 DOI: 10.1111/pim.12807] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/27/2020] [Accepted: 10/27/2020] [Indexed: 12/14/2022]
Abstract
'Omics' technologies have facilitated the identification of hundreds to thousands of tick molecules that mediate tick feeding and play a role in the transmission of tick-borne diseases. Deep sequencing methodologies have played a key role in this knowledge accumulation, profoundly facilitating the study of the biology of disease vectors lacking reference genomes. For example, the nucleotide sequences of the entire set of tick salivary effectors, the so-called tick 'sialome', now contain at least one order of magnitude more transcript sequences compared to similar projects based on Sanger sequencing. Tick feeding is a complex and dynamic process, and while the dynamic 'sialome' is thought to mediate tick feeding success, exactly how transcriptome dynamics relate to tick-host-pathogen interactions is still largely unknown. The identification and, importantly, the functional analysis of the tick 'sialome' is expected to shed light on this 'black box'. This information will be crucial for developing strategies to block pathogen transmission, not only for anti-tick vaccine development but also the discovery and development of new, pharmacologically active compounds for human diseases.
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Affiliation(s)
- Larissa Almeida Martins
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 37005, Czech Republic
| | - Chaima Bensaoud
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 37005, Czech Republic
| | - Jan Kotál
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 37005, Czech Republic.,Department of Medical Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Jindřich Chmelař
- Department of Medical Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Michail Kotsyfakis
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, České Budějovice, 37005, Czech Republic.,Department of Medical Biology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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18
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Mans BJ. Quantitative Visions of Reality at the Tick-Host Interface: Biochemistry, Genomics, Proteomics, and Transcriptomics as Measures of Complete Inventories of the Tick Sialoverse. Front Cell Infect Microbiol 2020; 10:574405. [PMID: 33042874 PMCID: PMC7517725 DOI: 10.3389/fcimb.2020.574405] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/13/2020] [Indexed: 12/19/2022] Open
Abstract
Species have definitive genomes. Even so, the transcriptional and translational products of the genome are dynamic and subject to change over time. This is especially true for the proteins secreted by ticks at the tick-host feeding interface that represent a complex system known as the sialoverse. The sialoverse represent all of the proteins derived from tick salivary glands for all tick species that may be involved in tick-host interaction and the modulation of the host's defense mechanisms. The current study contemplates the advances made over time to understand and describe the complexity present in the sialoverse. Technological advances at given periods in time allowed detection of functions, genes, and proteins enabling a deeper insight into the complexity of the sialoverse and a concomitant expansion in complexity with as yet, no end in sight. The importance of systematic classification of the sialoverse is highlighted with the realization that our coverage of transcriptome and proteome space remains incomplete, but that complete descriptions may be possible in the future. Even so, analysis and integration of the sialoverse into a comprehensive understanding of tick-host interactions may require further technological advances given the high level of expected complexity that remains to be uncovered.
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Affiliation(s)
- Ben J Mans
- Epidemiology, Parasites and Vectors, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa.,Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa.,Department of Life and Consumer Sciences, University of South Africa, Pretoria, South Africa
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19
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Etebari K, Lindsay KR, Ward AL, Furlong MJ. Australian sugarcane soldier fly's salivary gland transcriptome in response to starvation and feeding on sugarcane crops. INSECT SCIENCE 2020; 27:708-720. [PMID: 30946538 DOI: 10.1111/1744-7917.12676] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/27/2019] [Accepted: 03/31/2019] [Indexed: 06/09/2023]
Abstract
The soldier fly is an endemic pest of sugarcane in Australia. Small numbers of larvae can cause significant damage to roots and reduce the crop yields. Little is known about the composition and function of the soldier fly salivary gland, its secretions, and their roles in insect-plant interactions. In this study, we performed transcriptome analysis of the salivary glands of starved and sugarcane root-fed soldier fly larvae. A total of 31 119 highly expressed assembled contigs were identified in the salivary glands and almost 50% of them showed high levels of similarity to known proteins in Nr databases. Of all the obtained contigs, only 9727 sequences contain an open reading frame of over 100 amino acids. Around 31% of contigs were predicted to encode secretory proteins, including some digestive and detoxifying enzymes and potential effectors. Some known salivary secreted peptides such as serine protease, cysteine proteinase inhibitors, antimicrobial peptides and venom proteins were among the top 100 highly expressed genes. Differential gene expression analysis revealed significant modulation of 850 transcripts in salivary glands upon exposure to plant roots or starvation stress. Here, we identified some venom proteins which were significantly upregulated in the salivary glands of soldier fly larvae exposed to sugarcane roots. In other insects and nematodes some of these proteins have been used to manipulate host plant defense systems and facilitate the invasion of the host plant. These findings provide a further insight into the identification of potential effector proteins involved in soldier fly-sugarcane interactions.
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Affiliation(s)
- Kayvan Etebari
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
| | | | - Andrew L Ward
- Sugar Research Australia, Indooroopilly, QLD, Australia
| | - Michael J Furlong
- School of Biological Sciences, The University of Queensland, Brisbane, QLD, Australia
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20
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Integrated analysis of sialotranscriptome and sialoproteome of the brown dog tick Rhipicephalus sanguineus (s.l.): Insights into gene expression during blood feeding. J Proteomics 2020; 229:103899. [PMID: 32673754 DOI: 10.1016/j.jprot.2020.103899] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/30/2020] [Accepted: 07/08/2020] [Indexed: 02/08/2023]
Abstract
Tick salivary glands secrete a complex saliva into their hosts which modulates vertebrate hemostasis, immunity and tissue repair mechanisms. Transcriptomic studies revealed a large number of transcripts coding for structural and secreted protein products in a single tick species. These transcripts are organized in several large families according to their products. Not all transcripts are expressed at the same time, transcription profile switches at intervals, characterizing the phenomenon of "sialome switching". In this work, using transcriptomic and proteomic analysis we explored the sialome of Rhipicephalus sanguineus (s.l.) adult female ticks feeding on a rabbit. The correlations between transcriptional and translational results in the different groups were evaluated, confirming the "sialome switching" and validating the idea that the expression switch may serve as a mechanism of escape from the host immunity. Recombination breakpoints were identified in lipocalin and metalloprotease families, indicating this mechanism could be a possible source of diversity in the tick sialome. Another remarkable observation was the identification of host-derived proteins as a component of tick salivary gland content. These results and disclosed sequences contribute to our understanding of tick feeding biology, to the development of novel anti-tick methods, and to the discovery of novel pharmacologically active products. SIGNIFICANCE: Ticks are a burden by themselves to humans and animals, and vectors of viral, bacterial, protozoal and helminthic diseases. Their saliva has anti-clotting, anti-platelet, vasodilatory and immunomodulatory activities that allows successful feeding and pathogen transmission. Previous transcriptomic studies indicate ticks to have over one thousand transcripts coding for secreted salivary proteins. These transcripts code for proteins of diverse families, but not all are transcribed simultaneously, but rather transiently, in a succession. Here we explored the salivary transcriptome and proteome of the brown dog tick, Rhipicephalus sanguineus. A protein database of over 20 thousand sequences was "de novo" assembled from over 600 million nucleotide reads, from where over two thousand polypeptides were identified by mass spectrometry. The proteomic data was shown to vary in time with the transcription profiles, validating the idea that the expression switch may serve as a mechanism of escape from the host immunity. Analysis of the transcripts coding for lipocalin and metalloproteases indicate their genes to contain signals of breakpoint recombination suggesting a new mechanism responsible for the large diversity in tick salivary proteins. These results and the disclosed sequences contribute to our understanding of the success ticks enjoy as ectoparasites, to the development of novel anti-tick methods, and to the discovery of novel pharmacologically active products.
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21
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Martins LA, Kotál J, Bensaoud C, Chmelař J, Kotsyfakis M. Small protease inhibitors in tick saliva and salivary glands and their role in tick-host-pathogen interactions. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140336. [DOI: 10.1016/j.bbapap.2019.140336] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 12/22/2022]
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22
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Giachetto PF, Cunha RC, Nhani A, Garcia MV, Ferro JA, Andreotti R. Gene Expression in the Salivary Gland of Rhipicephalus (Boophilus) microplus Fed on Tick-Susceptible and Tick-Resistant Hosts. Front Cell Infect Microbiol 2020; 9:477. [PMID: 32039052 PMCID: PMC6985549 DOI: 10.3389/fcimb.2019.00477] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/24/2019] [Indexed: 01/10/2023] Open
Abstract
The success of cattle tick fixation largely depends on the secretion of substances that alter the immune response of the host. The majority of these substances are expressed by the parasite salivary gland and secreted in tick saliva. It is known that hosts can mount immune responses against ticks and bovine European breeds, and bovine industrial crossbreeds are more susceptible to infestations than are Bos indicus cattle. To identify candidates for the development of novel control strategies for the cattle tick Rhipicephalus (Boophilus) microplus, a salivary gland transcriptome analysis of engorged females fed on susceptible or resistant hosts was performed. Using RNA-Seq, transcriptomes were de novo assembled and produced a total of 235,451 contigs with 93.3% transcriptome completeness. Differential expression analysis identified 137 sequences as differentially expressed genes (DEGs) between ticks raised on tick-susceptible or tick-resistant cattle. DEGs predicted to be secreted proteins include innexins, which are transmembrane proteins that form gap junction channels; the transporters Na+/dicarboxylate, Na+/tricarboxylate, and phosphate transporter and a putative monocarboxylate transporter; a phosphoinositol 4-phosphate adaptor protein; a cysteine-rich protein containing a trypsin inhibitor-like (TIL) domain; a putative defense protein 3 containing a reeler domain; and an F-actin-uncapping protein LRRC16A with a CARMIL_C domain; these genes were upregulated in ticks fed on tick-susceptible cattle. DEGs predicted to be non-secreted proteins included a small heat shock protein and the negative elongation factor B-like, both acting in a coordinated manner to increase HSP transcript levels in the salivary glands of the ticks fed on tick-susceptible cattle; the 26S protease regulatory subunit 6B and another chaperone with similarity to calnexin, also upregulated in ticks fed on tick-susceptible cattle; an EF-hand calcium binding protein and a serine carboxypeptidase (SCP), both involved in the blood coagulation cascade and upregulated in ticks fed on tick-susceptible cattle; and two ribosomal proteins, the 60S acidic ribosomal protein P2 and the 60S ribosomal protein L19. These results help to characterize cattle tick salivary gland gene expression in tick-susceptible and tick-resistant hosts and suggest new putative targets for the control of tick infestations, as those genes involved in the mechanism of stress response during blood feeding.
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Affiliation(s)
| | - Rodrigo Casquero Cunha
- Bolsista do CNPq (157460/2018-5), Programa de Pós-Graduação em Biotecnologia, Universidade Federal de Pelotas, Pelotas, Brazil
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23
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De Novo RNA-seq and Functional Annotation of Haemaphysalis longicornis. Acta Parasitol 2019; 64:807-820. [PMID: 31418165 DOI: 10.2478/s11686-019-00103-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Accepted: 08/01/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE Haemaphysalis longicornis (Neumann) is a hematophagous tick widely distributed in northern China. It not only causes enormous economic loss to animal husbandry, but also as a vector and reservoir of various zoonotic pathogens, it spreads natural focal diseases, such as severe fever with thrombocytopenia syndrome, seriously threatening human health. Lack of transcriptomic and genomic data from H. longicornis limits the study of this important medical vector. METHODS The engorged female H. longicornis from Gansu, China, was used for RNA extraction, de novo RNA-seq, functional annotation, and ORF prediction. RESULTS As a result, 53.09 million clean reads (98.88%) with a GC content of 54.29% were obtained. A total of 65,916 Unigenes were assembled, of which 34.59% (23,330) were successfully annotated. Of these Unigenes, 22,587 (34.27%) were annotated to species by NCBI non-redundant protein (nr). Ixodes scapularis, Limulus polyphemus, Parasteatoda tepidariorum, Stegodyphus mimosarum, and Metaseiulus occidentalis were the top BLAST hit species, accounting for 47.23%, 9.58%, 4.11%, 3.50%, and 2.69%, respectively. A total of 29,182 ORFs were predicted, and 35 complete ORFs for functional genes were identified, including ORFs involved in digestion (14), stress responses (8), anticoagulation (3), reproduction (3), antimicrobial (2), drug resistance (2), movement (2), autophagy (1), and immunity (1), respectively. The Unigene ORFs encoding cathepsin and heat shock proteins were further analyzed phylogenetically. CONCLUSION De novo RNA-seq and functional annotation of H. longicornis were successfully completed for the first time, providing a molecular data resource for further research on blood-sucking, pathogen transmission mechanisms, and effective prevention and control strategies.
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24
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Padula AM, Leister EM, Webster RA. Tick paralysis in dogs and cats in Australia: treatment and prevention deliverables from 100 years of research. Aust Vet J 2019; 98:53-59. [PMID: 31762008 DOI: 10.1111/avj.12891] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 10/20/2019] [Accepted: 10/21/2019] [Indexed: 02/02/2023]
Abstract
This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all - a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.
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Affiliation(s)
- A M Padula
- Australian Venom Research Unit, Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Melbourne, Parkville, Victoria, Australia.,Padula Serums Pty Ltd, Bairnsdale, Victoria, Australia
| | - E M Leister
- Pet Intensive Care Unit (Pet ICU), Underwood, Queensland, 4119, Australia
| | - R A Webster
- Pet Intensive Care Unit (Pet ICU), Underwood, Queensland, 4119, Australia
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25
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Charrier NP, Hermouet A, Hervet C, Agoulon A, Barker SC, Heylen D, Toty C, McCoy KD, Plantard O, Rispe C. A transcriptome-based phylogenetic study of hard ticks (Ixodidae). Sci Rep 2019; 9:12923. [PMID: 31501478 PMCID: PMC6733903 DOI: 10.1038/s41598-019-49641-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/19/2019] [Indexed: 11/30/2022] Open
Abstract
Hard ticks are widely distributed across temperate regions, show strong variation in host associations, and are potential vectors of a diversity of medically important zoonoses, such as Lyme disease. To address unresolved issues with respect to the evolutionary relationships among certain species or genera, we produced novel RNA-Seq data sets for nine different Ixodes species. We combined this new data with 18 data sets obtained from public databases, both for Ixodes and non-Ixodes hard tick species, using soft ticks as an outgroup. We assembled transcriptomes (for 27 species in total), predicted coding sequences and identified single copy orthologues (SCO). Using Maximum-likelihood and Bayesian frameworks, we reconstructed a hard tick phylogeny for the nuclear genome. We also obtained a mitochondrial DNA-based phylogeny using published genome sequences and mitochondrial sequences derived from the new transcriptomes. Our results confirm previous studies showing that the Ixodes genus is monophyletic and clarify the relationships among Ixodes sub-genera. This work provides a baseline for studying the evolutionary history of ticks: we indeed found an unexpected acceleration of substitutions for mitochondrial sequences of Prostriata, and for nuclear and mitochondrial genes of two species of Rhipicephalus, which we relate with patterns of genome architecture and changes of life-cycle, respectively.
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Affiliation(s)
| | | | | | | | - Stephen C Barker
- Department of Parasitology, School of Chemistry & Molecular Biosciences, The University of Queensland, Brisbane, Qld, Australia
| | - Dieter Heylen
- Evolutionary Ecology Group, Department of Biology, University of Antwerp, Wilrijk, Belgium
- Interuniversity Institute for Biostatistics and statistical Bioinformatics, Hasselt University, Diepenbeek, Belgium
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA
| | - Céline Toty
- Laboratoire MIVEGEC (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution & Contrôle), Université de Montpellier, Centre National de la Recherche Scientifique (UMR5290), Institut de Recherche pour le Développement (UR224), Montpellier, France
| | - Karen D McCoy
- Laboratoire MIVEGEC (Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution & Contrôle), Université de Montpellier, Centre National de la Recherche Scientifique (UMR5290), Institut de Recherche pour le Développement (UR224), Montpellier, France
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Cabezas-Cruz A, Tonk M, Bleackley MR, Valdés JJ, Barrero RA, Hernández-Jarguín A, Moutailler S, Vilcinskas A, Richard-Forget F, Anderson MA, Rodriguez-Valle M. Antibacterial and antifungal activity of defensins from the Australian paralysis tick, Ixodes holocyclus. Ticks Tick Borne Dis 2019; 10:101269. [PMID: 31445875 DOI: 10.1016/j.ttbdis.2019.101269] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/27/2019] [Accepted: 08/15/2019] [Indexed: 12/21/2022]
Abstract
Tick innate immunity involves humoral and cellular responses. Among the humoral effector molecules in ticks are the defensins which are a family of small peptides with a conserved γ-core motif that is crucial for their antimicrobial activity. Defensin families have been identified in several hard and soft tick species. However, little is known about the presence and antimicrobial activity of defensins from the Australian paralysis tick Ixodes holocyclus. In this study the I. holocyclus transcriptome was searched for the presence of defensins. Unique and non-redundant defensin sequences were identified and designated as holosins 1 - 5. The antimicrobial activity of holosins 2 and 3 and of the predicted γ-cores of holosins 1-4 (HoloTickCores 1-4), was assessed using Gram-negative and Gram-positive bacteria as well as the fungus Fusarium graminearum and the yeast Candida albicans. All holosins had molecular features that are conserved in other tick defensins. Furthermore holosins 2 and 3 were very active against the Gram-positive bacteria Staphylococcus aureus and Listeria grayi. Holosins 2 and 3 were also active against F. graminearum and C. albicans and 5 μM of peptide abrogate the growth of these microorganisms. The activity of the synthetic γ-cores was lower than that of the mature defensins apart from HoloTickCore 2 which had activity comparable to mature holosin 2 against the Gram-negative bacterium Escherichia coli. This study reveals the presence of a multigene defensin family in I. holocyclus with wide antimicrobial activity.
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Affiliation(s)
- Alejandro Cabezas-Cruz
- UMR BIPAR, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, 94700, France.
| | - Miray Tonk
- Institute for Insect Biotechnology, Justus Liebig University of Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany; LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany
| | - Mark R Bleackley
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - James J Valdés
- Faculty of Science, University of South Bohemia, 37005, České Budějovice, Czech Republic; Institute of Parasitology, Biology Center, Czech Academy of Sciences, 37005, České Budějovice, Czech Republic; Department of Virology, Veterinary Research Institute, Brno, Czech Republic
| | - Roberto A Barrero
- Centre for Comparative Genomics, Murdoch University, Perth, WA 6150, Australia
| | | | - Sara Moutailler
- UMR BIPAR, INRA, ANSES, Ecole Nationale Vétérinaire d'Alfort, Université Paris-Est, Maisons-Alfort, 94700, France
| | - Andreas Vilcinskas
- Institute for Insect Biotechnology, Justus Liebig University of Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany; LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology, Department of Bioresources, Winchester Strasse 2, 35394, Giessen, Germany
| | | | - Marilyn A Anderson
- LOEWE Centre for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany
| | - Manuel Rodriguez-Valle
- Queensland Alliance for Agriculture & Food Innovation, The University of Queensland, St. Lucia, Queensland 4072, Australia.
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Mans BJ. Chemical Equilibrium at the Tick-Host Feeding Interface:A Critical Examination of Biological Relevance in Hematophagous Behavior. Front Physiol 2019; 10:530. [PMID: 31118903 PMCID: PMC6504839 DOI: 10.3389/fphys.2019.00530] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/15/2019] [Indexed: 12/14/2022] Open
Abstract
Ticks secrete hundreds to thousands of proteins into the feeding site, that presumably all play important functions in the modulation of host defense mechanisms. The current review considers the assumption that tick proteins have functional relevance during feeding. The feeding site may be described as a closed system and could be treated as an ideal equilibrium system, thereby allowing modeling of tick-host interactions in an equilibrium state. In this equilibrium state, the concentration of host and tick proteins and their affinities will determine functional relevance at the tick-host interface. Using this approach, many characterized tick proteins may have functional relevant concentrations and affinities at the feeding site. Conversely, the feeding site is not an ideal closed system, but is dynamic and changing, leading to possible overestimation of tick protein concentration at the feeding site and consequently an overestimation of functional relevance. Ticks have evolved different possible strategies to deal with this dynamic environment and overcome the barrier that equilibrium kinetics poses to tick feeding. Even so, cognisance of the limitations that equilibrium binding place on deductions of functional relevance should serve as an important incentive to determine both the concentration and affinity of tick proteins proposed to be functional at the feeding site.
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Affiliation(s)
- Ben J. Mans
- Epidemiology, Parasites and Vectors, Agricultural Research Council-Onderstepoort Veterinary Research, Pretoria, South Africa
- Department of Veterinary Tropical Diseases, University of Pretoria, Pretoria, South Africa
- Department of Life and Consumer Sciences, University of South Africa, Pretoria, South Africa
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28
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Meeting the challenge of tick-borne disease control: A proposal for 1000 Ixodes genomes. Ticks Tick Borne Dis 2018; 10:213-218. [PMID: 30266208 DOI: 10.1016/j.ttbdis.2018.08.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 08/07/2018] [Accepted: 08/14/2018] [Indexed: 12/12/2022]
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Santibáñez-López CE, Ontano AZ, Harvey MS, Sharma PP. Transcriptomic Analysis of Pseudoscorpion Venom Reveals a Unique Cocktail Dominated by Enzymes and Protease Inhibitors. Toxins (Basel) 2018; 10:E207. [PMID: 29783636 PMCID: PMC5983263 DOI: 10.3390/toxins10050207] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 05/15/2018] [Accepted: 05/16/2018] [Indexed: 12/19/2022] Open
Abstract
Transcriptomic and genomic analyses have illuminated the diversity of venoms in three of the four venomous arachnid orders (scorpions, spiders, and ticks). To date, no venom gland transcriptome analysis has been available for pseudoscorpions, the fourth venomous arachnid lineage. To redress this gap, we sequenced an mRNA library generated from the venom glands of the species Synsphyronus apimelus (Garypidae). High-throughput sequencing by the Illumina protocol, followed by de novo assembly, resulted in a total of 238,331 transcripts. From those, we annotated 131 transcripts, which code for putative peptides/proteins with similar sequences to previously reported venom components available from different arachnid species in protein databases. Transcripts putatively coding for enzymes showed the richest diversity, followed by other venom components such as peptidase inhibitors, cysteine-rich peptides, and thyroglobulin 1-like peptides. Only 11 transcripts were found that code for putatively low molecular mass spider toxins. This study constitutes the first report of the diversity of components within pseudoscorpion venom.
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Affiliation(s)
- Carlos E Santibáñez-López
- Department of Integrative Biology, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, WI 53706, USA.
- Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Av. Universidad 3000, Coyoacán, Ciudad de México C.P. 04510, Mexico.
| | - Andrew Z Ontano
- Department of Integrative Biology, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, WI 53706, USA.
| | - Mark S Harvey
- Department of Terrestrial Zoology, Western Australian Museum, Locked Bag 49, Welshpool DC, Western Australia 6986, Australia.
| | - Prashant P Sharma
- Department of Integrative Biology, University of Wisconsin-Madison, 430 Lincoln Drive, Madison, WI 53706, USA.
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30
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Pienaar R, Neitz AWH, Mans BJ. Tick Paralysis: Solving an Enigma. Vet Sci 2018; 5:E53. [PMID: 29757990 PMCID: PMC6024606 DOI: 10.3390/vetsci5020053] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 05/04/2018] [Accepted: 05/09/2018] [Indexed: 11/17/2022] Open
Abstract
In comparison to other arachnids, ticks are major vectors of disease, but less than 8% of the known species are capable of inducing paralysis, as compared to the ~99⁻100% arachnids that belong to venomous classes. When considering the potential monophyly of venomous Arachnida, this review reflects on the implications regarding the classification of ticks as venomous animals and the possible origin of toxins. The origin of tick toxins is compared with scorpion and spider toxins and venoms based on their significance, functionality, and structure in the search to find homologous venomous characters. Phenotypic evaluation of paralysis, as caused by different ticks, demonstrated the need for expansion on existing molecular data of pure isolated tick toxins because of differences and discrepancies in available data. The use of in-vivo, in-vitro, and in-silico assays for the purification and characterization of paralysis toxins were critically considered, in view of what may be considered to be a paralysis toxin. Purified toxins should exhibit physiologically relevant activity to distinguish them from other tick-derived proteins. A reductionist approach to identify defined tick proteins will remain as paramount in the search for defined anti-paralysis vaccines.
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Affiliation(s)
- Ronel Pienaar
- Epidemiology, Parasites and Vectors, Agricultural Research Council⁻Onderstepoort Veterinary Research, Onderstepoort, Pretoria 0110, South Africa.
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa.
| | - Albert W H Neitz
- Division of Biochemistry, University of Pretoria, Hatfield, Pretoria 0028, South Africa.
| | - Ben J Mans
- Epidemiology, Parasites and Vectors, Agricultural Research Council⁻Onderstepoort Veterinary Research, Onderstepoort, Pretoria 0110, South Africa.
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0110, South Africa.
- Department of Life and Consumer Sciences, University of South Africa, Florida, Johannesburg 1710, South Africa.
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31
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O'Brien CA, Hall RA, Lew-Tabor A. Could Australian ticks harbour emerging viral pathogens? MICROBIOLOGY AUSTRALIA 2018. [DOI: 10.1071/ma18060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Tick-borne viruses contribute significantly to the disease burden in Europe, Asia and the US. Historically, some of the most well-known viruses from this group include the human pathogens, tick-borne encephalitis virus and Crimean-Congo haemorrhagic fever virus. More recently multiple emerging tick-borne viruses have been associated with severe disease in humans with Bourbon virus and Heartland virus isolated from patients in the US and severe fever with thrombocytopenia syndrome virus reported from China, Japan, and South Korea. Such examples highlight the need for broader approaches to survey arthropod pathogens, to encompass not only known but novel pathogens circulating in Australian tick populations.
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