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Grasperge BJ, Morgan TW, Paddock CD, Peterson KE, Macaluso KR. Feeding by Amblyomma maculatum (Acari: Ixodidae) enhances Rickettsia parkeri (Rickettsiales: Rickettsiaceae) infection in the skin. JOURNAL OF MEDICAL ENTOMOLOGY 2014; 51:855-863. [PMID: 25118419 PMCID: PMC4214552 DOI: 10.1603/me13248] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Rickettsia parkeri Luckman (Rickettsiales: Rickettsiaceae), a member of the spotted fever group of Rickettsia, is the tick-borne causative agent of a newly recognized, eschar-associated rickettsiosis. Because of its relatively recent designation as a pathogen, few studies have examined the pathogenesis of transmission of R. parkeri to the vertebrate host. To further elucidate the role of tick feeding in rickettsial infection of vertebrates, nymphal Amblyomma maculatum Koch (Acari: Ixodidae) were fed on C3H/HeJ mice intradermally inoculated with R. parkeri (Portsmouth strain). The ticks were allowed to feed to repletion, at which time samples were taken for histopathology, immunohistochemistry (IHC), quantitative polymerase chain reaction (qPCR) for rickettsial quantification, and reverse transcriptase polymerase chain reaction (RT-PCR) for expression of Itgax, Mcp1, and Il1beta. The group of mice that received intradermal inoculation of R. parkeri with tick feeding displayed significant increases in rickettsial load and IHC staining, but not in cytokine expression, when compared with the group of mice that received intradermal inoculation of R. parkeri without tick feeding. Tick feeding alone was associated with histopathologic changes in the skin, but these changes, and particularly vascular pathology, were more pronounced in the skin of mice inoculated previously with R. parkeri and followed by tick feeding. The marked differences in IHC staining and qPCR for the R. parkeri with tick feeding group strongly suggest an important role for tick feeding in the early establishment of rickettsial infection in the skin.
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Affiliation(s)
- Britton J. Grasperge
- Vector-borne Disease Laboratories, Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA 70803
| | - Timothy W. Morgan
- Department of Pathobiology and Population Medicine, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762
| | - Christopher D. Paddock
- Infectious Diseases Pathology Branch, Centers for Disease Control and Prevention, Atlanta, GA 30341
| | - Karin E. Peterson
- Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, MT 59840
| | - Kevin R. Macaluso
- Vector-borne Disease Laboratories, Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Skip Bertman Drive, Baton Rouge, LA 70803
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Koči J, Simo L, Park Y. Autocrine/paracrine dopamine in the salivary glands of the blacklegged tick Ixodes scapularis. JOURNAL OF INSECT PHYSIOLOGY 2014; 62:39-45. [PMID: 24503219 PMCID: PMC4006075 DOI: 10.1016/j.jinsphys.2014.01.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/16/2014] [Accepted: 01/21/2014] [Indexed: 05/08/2023]
Abstract
Dopamine (DA) is known to be the most potent activator of tick salivary secretion, which is an essential component of successful tick feeding. We examined the quantitative changes of catecholamines using a method coupling high-pressure liquid chromatography with electrochemical detection (HPLC-ECD). We also investigated the levels of catecholamines conjugated to other molecules utilising appropriate methods to hydrolyse the conjugates. Three different biological samples, salivary glands, synganglia, ovaries and haemolymph were compared, and the largest quantity of DA was detected in salivary gland extracts (up to ∼100pg/tick), supporting the hypothesis that autocrine/paracrine dopamine activates salivary secretion. Quantitative changes of catecholamines in the salivary glands over the entire blood feeding duration were examined. The amount of dopamine in the salivary glands increased until the day 5 of feeding, at which the rapid engorgement phase began. We also detected a small but significant amount of norepinephrine in the salivary glands. Interestingly, saliva collected after induction of salivary secretion by the cholinergic agonist pilocarpine contained a large amount of DA sulphate with a trace amount of DA, suggesting a potential biological role of DA sulphate in tick saliva.
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Affiliation(s)
- Juraj Koči
- Department of Entomology, Kansas State University, 123 Waters Hall, Manhattan, KS 66506, USA.
| | - Ladislav Simo
- Department of Entomology, Kansas State University, 123 Waters Hall, Manhattan, KS 66506, USA.
| | - Yoonseong Park
- Department of Entomology, Kansas State University, 123 Waters Hall, Manhattan, KS 66506, USA.
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Kazimírová M, Štibrániová I. Tick salivary compounds: their role in modulation of host defences and pathogen transmission. Front Cell Infect Microbiol 2013; 3:43. [PMID: 23971008 PMCID: PMC3747359 DOI: 10.3389/fcimb.2013.00043] [Citation(s) in RCA: 197] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Accepted: 07/26/2013] [Indexed: 01/24/2023] Open
Abstract
Ticks require blood meal to complete development and reproduction. Multifunctional tick salivary glands play a pivotal role in tick feeding and transmission of pathogens. Tick salivary molecules injected into the host modulate host defence responses to the benefit of the feeding ticks. To colonize tick organs, tick-borne microorganisms must overcome several barriers, i.e., tick gut membrane, tick immunity, and moulting. Tick-borne pathogens co-evolved with their vectors and hosts and developed molecular adaptations to avoid adverse effects of tick and host defences. Large gaps exist in the knowledge of survival strategies of tick-borne microorganisms and on the molecular mechanisms of tick-host-pathogen interactions. Prior to transmission to a host, the microorganisms penetrate and multiply in tick salivary glands. As soon as the tick is attached to a host, gene expression and production of salivary molecules is upregulated, primarily to facilitate feeding and avoid tick rejection by the host. Pathogens exploit tick salivary molecules for their survival and multiplication in the vector and transmission to and establishment in the hosts. Promotion of pathogen transmission by bioactive molecules in tick saliva was described as saliva-assisted transmission (SAT). SAT candidates comprise compounds with anti-haemostatic, anti-inflammatory and immunomodulatory functions, but the molecular mechanisms by which they mediate pathogen transmission are largely unknown. To date only a few tick salivary molecules associated with specific pathogen transmission have been identified and their functions partially elucidated. Advanced molecular techniques are applied in studying tick-host-pathogen interactions and provide information on expression of vector and pathogen genes during pathogen acquisition, establishment and transmission. Understanding the molecular events on the tick-host-pathogen interface may lead to development of new strategies to control tick-borne diseases.
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Affiliation(s)
- Mária Kazimírová
- Institute of Zoology, Slovak Academy of Sciences Bratislava, Slovakia.
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54
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Gassner F, Takken W, Plas CLVD, Kastelein P, Hoetmer AJ, Holdinga M, van Overbeek LS. Rodent species as natural reservoirs of Borrelia burgdorferi sensu lato in different habitats of Ixodes ricinus in The Netherlands. Ticks Tick Borne Dis 2013; 4:452-8. [PMID: 23891104 DOI: 10.1016/j.ttbdis.2012.11.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 05/15/2013] [Accepted: 05/18/2013] [Indexed: 11/18/2022]
Abstract
Rodents are natural reservoirs for human pathogenic spirochaetes of the Borrelia burgdorferi complex [B. burgdorferi sensu lato (s.l.)], and the pathogens are transmitted by Ixodes ricinus ticks to humans in The Netherlands. B. burgdorferi s.l. infection prevalence in questing ticks, rodents, and ticks feeding on these rodents, all sampled within the same short time span of five days in three different areas in The Netherlands, were compared in order to establish the relationship between ticks, reservoir hosts, and B. burgdorferi s.l. Questing nymphs were found in all 3 areas and numbers differed per area and even per site within areas. Infection prevalence in questing nymphs ranged between 0 and 20%. Apodemus sylvaticus and Myodes glareolus were the dominant rodents captured, and their numbers differed per area. Infection prevalence, determined by ear biopsies, ranged between 0 and 33.3% for both rodent species. Larvae were most frequently found feeding on these rodents, and their Borrelia infection prevalence ranged between 0 and 6.3% (A. sylvaticus) and between 0 and 29.4% (M. glareolus). The burden of nymphs feeding on rodents was low and varied per area with only 2 of 42 nymphs infected. Comparisons made on the basis of infection prevalence indicated that there was no clear relationship between rodents and questing nymphs when sampled within the same short time span. However, a possible relationship was present when questing ticks were sampled over longer periods in time (months) within or near the same areas (range of infection prevalence between 3.7 and 39.4). Confounding factors thus play a role in the interaction between rodents, ticks, and B. burgdorferi s.l., and it is very likely that other reservoir host species are responsible for the observed fluctuations. It is concluded that the local variations in rodent-Borrelia-tick interactions only partially explain the Lyme borreliosis risk in the sites studied and that other ecological determinants, notably vertebrate hosts and vegetation structure, should be incorporated in future studies of Lyme borreliosis risk.
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Affiliation(s)
- Fedor Gassner
- Laboratory of Entomology, Wageningen University and Research Centre, P.O. Box 8031, 6700 EH Wageningen, The Netherlands
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Hajdušek O, Síma R, Ayllón N, Jalovecká M, Perner J, de la Fuente J, Kopáček P. Interaction of the tick immune system with transmitted pathogens. Front Cell Infect Microbiol 2013; 3:26. [PMID: 23875177 PMCID: PMC3712896 DOI: 10.3389/fcimb.2013.00026] [Citation(s) in RCA: 169] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 06/13/2013] [Indexed: 12/04/2022] Open
Abstract
Ticks are hematophagous arachnids transmitting a wide variety of pathogens including viruses, bacteria, and protozoans to their vertebrate hosts. The tick vector competence has to be intimately linked to the ability of transmitted pathogens to evade tick defense mechanisms encountered on their route through the tick body comprising midgut, hemolymph, salivary glands or ovaries. Tick innate immunity is, like in other invertebrates, based on an orchestrated action of humoral and cellular immune responses. The direct antimicrobial defense in ticks is accomplished by a variety of small molecules such as defensins, lysozymes or by tick-specific antimicrobial compounds such as microplusin/hebraein or 5.3-kDa family proteins. Phagocytosis of the invading microbes by tick hemocytes is likely mediated by the primordial complement-like system composed of thioester-containing proteins, fibrinogen-related lectins and convertase-like factors. Moreover, an important role in survival of the ingested microbes seems to be played by host proteins and redox balance maintenance in the tick midgut. Here, we summarize recent knowledge about the major components of tick immune system and focus on their interaction with the relevant tick-transmitted pathogens, represented by spirochetes (Borrelia), rickettsiae (Anaplasma), and protozoans (Babesia). Availability of the tick genomic database and feasibility of functional genomics based on RNA interference greatly contribute to the understanding of molecular and cellular interplay at the tick-pathogen interface and may provide new targets for blocking the transmission of tick pathogens.
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Affiliation(s)
- Ondřej Hajdušek
- Biological Centre ASCR, Institute of Parasitology České Budějovice, Czech Republic
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56
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Kung F, Anguita J, Pal U. Borrelia burgdorferi and tick proteins supporting pathogen persistence in the vector. Future Microbiol 2013; 8:41-56. [PMID: 23252492 DOI: 10.2217/fmb.12.121] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Borrelia burgdorferi, a pathogen transmitted by Ixodes ticks, is responsible for a prevalent illness known as Lyme disease, and a vaccine for human use is unavailable. Recently, genome sequences of several B. burgdorferi strains and Ixodes scapularis ticks have been determined. In addition, remarkable progress has been made in developing molecular genetic tools to study the pathogen and vector, including their intricate relationship. These developments are helping unravel the mechanisms by which Lyme disease pathogens survive in a complex enzootic infection cycle. Notable discoveries have already contributed to understanding the spirochete gene regulation accounting for the temporal and spatial expression of B. burgdorferi genes during distinct phases of the lifecycle. A number of pathogen and vector gene products have also been identified that contribute to microbial virulence and/or persistence. These research directions will enrich our knowledge of vector-borne infections and contribute towards the development of preventative strategies against Lyme disease.
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Affiliation(s)
- Faith Kung
- Department of Veterinary Medicine & Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park, MD 20742, USA
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57
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Embers ME, Narasimhan S. Vaccination against Lyme disease: past, present, and future. Front Cell Infect Microbiol 2013; 3:6. [PMID: 23407755 PMCID: PMC3569838 DOI: 10.3389/fcimb.2013.00006] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/20/2013] [Indexed: 12/01/2022] Open
Abstract
Lyme borreliosis is a zoonotic disease caused by Borrelia burgdorferi sensu lato bacteria transmitted to humans and domestic animals by the bite of an Ixodes spp. tick (deer tick). Despite improvements in diagnostic tests and public awareness of Lyme disease, the reported cases have increased over the past decade to approximately 30,000 per year. Limitations and failed public acceptance of a human vaccine, comprised of the outer surface A (OspA) lipoprotein of B. burgdorferi, led to its demise, yet current research has opened doors to new strategies for protection against Lyme disease. In this review we discuss the enzootic cycle of B. burgdorferi, and the unique opportunities it poses to block infection or transmission at different levels. We present the correlates of protection for this infectious disease, the pros and cons of past vaccination strategies, and new paradigms for future vaccine design that would include elements of both the vector and the pathogen.
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Affiliation(s)
- Monica E Embers
- Division of Bacteriology and Parasitology, Tulane National Primate Research Center, Covington, LA, USA.
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58
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Lyme disease vaccines. Vaccines (Basel) 2013. [DOI: 10.1016/b978-1-4557-0090-5.00055-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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59
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Marancik DP, Leary JH, Fast MM, Flajnik MF, Camus AC. Humoral response of captive zebra sharks Stegostoma fasciatum to salivary gland proteins of the leech Branchellion torpedinis. FISH & SHELLFISH IMMUNOLOGY 2012; 33:1000-1007. [PMID: 22963935 DOI: 10.1016/j.fsi.2012.08.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 08/09/2012] [Accepted: 08/17/2012] [Indexed: 06/01/2023]
Abstract
Parasitism by the marine leech Branchellion torpedinis is known to cause disease and mortality in captive elasmobranchs and is difficult to control when inadvertently introduced into public aquaria. Preliminary characterization of the salivary gland transcriptome of B. torpedinis has identified anticoagulants, proteases, and immunomodulators that may be secreted into host tissues to aid leech feeding. This retrospective study examined antigen-specific serum IgM responses in captive zebra sharks Stegostoma fasciatum to leech salivary gland extract. Antibody response was examined by ELISA and Western blot assays in 20 serum samples from six zebra sharks, with a 5 year history of leech infection, and 18 serum samples from 8 captive bred zebra sharks, with no history of leech exposure. ELISA demonstrated significantly higher serum IgM titers to salivary gland extract in exposed zebra sharks compared to the non-exposed population. No obvious trends in antibody titers were appreciated in exposed zebra sharks over a four-year period. One-dimensional and two-dimensional Western blot assays revealed IgM targeted specific salivary gland proteins within the 40, 55, 70 and 90 kD range. Antigenic proteins identified by liquid chromatography-tandem mass spectrometry and de novo peptide sequencing include a secreted disintegrin, metalloproteinase and thrombospondin motif containing protein (ADAMTS), tubulin, aldehyde dehydrogenase and two unknown proteins. Humoral immune responses to leech salivary gland proteins warrants further investigation as there may be options to exploit immune mechanisms to reduce parasite burdens in aquaria.
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Affiliation(s)
- David P Marancik
- Department of Pathology, University of Georgia, 501 D.W. Brooks Drive, Athens, GA 30602, USA.
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60
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Estrada-Peña A, Ayllón N, de la Fuente J. Impact of climate trends on tick-borne pathogen transmission. Front Physiol 2012; 3:64. [PMID: 22470348 PMCID: PMC3313475 DOI: 10.3389/fphys.2012.00064] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 03/05/2012] [Indexed: 01/01/2023] Open
Abstract
Recent advances in climate research together with a better understanding of tick-pathogen interactions, the distribution of ticks and the diagnosis of tick-borne pathogens raise questions about the impact of environmental factors on tick abundance and spread and the prevalence and transmission of tick-borne pathogens. While undoubtedly climate plays a role in the changes in distribution and seasonal abundance of ticks, it is always difficult to disentangle factors impacting on the abundance of tick hosts from those exerted by human habits. All together, climate, host abundance, and social factors may explain the upsurge of epidemics transmitted by ticks to humans. Herein we focused on tick-borne pathogens that affect humans with epidemic potential. Borrelia burgdorferi s.l. (Lyme disease), Anaplasma phagocytophilum (human granulocytic anaplasmosis), and tick-borne encephalitis virus (tick-borne encephalitis) are transmitted by Ixodes spp. Crimean-Congo hemorrhagic fever virus (Crimean-Congo hemorrhagic fever) is transmitted by Hyalomma spp. In this review, we discussed how vector tick species occupy the habitat as a function of different climatic factors, and how these factors impact on tick survival and seasonality. How molecular events at the tick-pathogen interface impact on pathogen transmission is also discussed. Results from statistically and biologically derived models are compared to show that while statistical models are able to outline basic information about tick distributions, biologically derived models are necessary to evaluate pathogen transmission rates and understand the effect of climatic variables and host abundance patterns on pathogen transmission. The results of these studies could be used to build early alert systems able to identify the main factors driving the subtle changes in tick distribution and seasonality and the prevalence of tick-borne pathogens.
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Affiliation(s)
- Agustín Estrada-Peña
- Department of Parasitology, Veterinary Faculty, University of ZaragozaZaragoza, Spain
| | - Nieves Ayllón
- Instituto de Investigación en Recursos CinegéticosCSIC–UCLM–JCCM, Ciudad Real, Spain
| | - José de la Fuente
- Instituto de Investigación en Recursos CinegéticosCSIC–UCLM–JCCM, Ciudad Real, Spain
- Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State UniversityStillwater, OK, USA
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McNally KL, Mitzel DN, Anderson JM, Ribeiro JMC, Valenzuela JG, Myers TG, Godinez A, Wolfinbarger JB, Best SM, Bloom ME. Differential salivary gland transcript expression profile in Ixodes scapularis nymphs upon feeding or flavivirus infection. Ticks Tick Borne Dis 2012; 3:18-26. [PMID: 22309855 PMCID: PMC3275779 DOI: 10.1016/j.ttbdis.2011.09.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 09/06/2011] [Indexed: 12/24/2022]
Abstract
Ixodid ticks are vectors of human diseases such as Lyme disease, babesiosis, anaplasmosis, and tick-borne encephalitis. These diseases cause significant morbidity and mortality worldwide and are transmitted to humans during tick feeding. The tick-host-pathogen interface is a complex environment where host responses are modulated by the molecules in tick saliva to enable the acquisition of a blood meal. Disruption of host responses at the site of the tick bite may also provide an advantage for pathogens to survive and replicate. Thus, the molecules in tick saliva not only aid the tick in securing a nutrient-rich blood meal, but can also enhance the transmission and acquisition of pathogens. To investigate the effect of feeding and flavivirus infection on the salivary gland transcript expression profile in ticks, a first-generation microarray was developed using ESTs from a cDNA library derived from Ixodes scapularis salivary glands. When the salivary gland transcript profile in ticks feeding over the course of 3 days was compared to that in unfed ticks, a dramatic increase in transcripts related to metabolism was observed. Specifically, 578 transcripts were up-regulated compared to 151 down-regulated transcripts in response to feeding. When specific time points post attachment were analyzed, a temporal pattern of gene expression was observed. When Langat virus-infected ticks were compared to mock-infected ticks, transcript expression changes were observed at all 3 days of feeding. Differentially regulated transcripts include putative secreted proteins, lipocalins, Kunitz domain-containing proteins, anti-microbial peptides, and transcripts of unknown function. These studies identify salivary gland transcripts that are differentially regulated during feeding or in the context of flavivirus infection in Ixodes scapularis nymphs, a medically important disease vector. Further analysis of these transcripts may identify salivary factors that affect the transmission or replication of tick-borne flaviviruses.
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Affiliation(s)
- Kristin L. McNally
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, 903 S Fourth St, Hamilton MT USA 59840
| | - Dana N. Mitzel
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, 903 S Fourth St, Hamilton MT USA 59840
| | | | - José M. C. Ribeiro
- Laboratory of Malaria and Vector Research, NIAID, NIH, Bethesda, MD USA 20892
| | - Jesus G. Valenzuela
- Laboratory of Malaria and Vector Research, NIAID, NIH, Bethesda, MD USA 20892
| | - Timothy G. Myers
- Genomic Technologies Section, Research Technologies Branch, NIAID, NIH, Bethesda, MD USA 20892
| | - Alvaro Godinez
- Genomic Technologies Section, Research Technologies Branch, NIAID, NIH, Bethesda, MD USA 20892
| | - James B. Wolfinbarger
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, 903 S Fourth St, Hamilton MT USA 59840
| | - Sonja M. Best
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, 903 S Fourth St, Hamilton MT USA 59840
| | - Marshall E. Bloom
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, 903 S Fourth St, Hamilton MT USA 59840
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Hughes AL, Friedman R. Distinctive amino acid composition profiles in salivary proteins of the tick Ixodes scapularis. Ticks Tick Borne Dis 2011; 2:219-24. [PMID: 22108016 DOI: 10.1016/j.ttbdis.2011.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 08/15/2011] [Accepted: 09/07/2011] [Indexed: 01/29/2023]
Abstract
Bioinformatic analysis of the amino acid composition of proteins of the tick Ixodes scapularis showed that, in comparison to other secreted proteins, salivary proteins in general have higher frequencies of polar residues and lower frequencies of the non-polar residues leucine and valine. Computer prediction of linear B-cell epitopes showed that polar residues were associated with the presence of high-quality epitopes and that tick salivary proteins included significantly more proteins with predicted high-quality epitopes than did other secreted proteins. The results provided no evidence that salivary proteins as a whole have evolved characteristics minimizing their antigenicity to the vertebrate host. Certain salivary proteins may indeed have evolved low antigenicity, but the I. scapularis sialome include at least some apparently antigenic proteins that might be tested experimentally to determine whether they would be suitable candidates for anti-tick vaccines.
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Affiliation(s)
- Austin L Hughes
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA.
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63
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Pichu S, Yalcin EB, Ribeiro JM, King RS, Mather TN. Molecular characterization of novel sulfotransferases from the tick, Ixodes scapularis. BMC BIOCHEMISTRY 2011; 12:32. [PMID: 21708020 PMCID: PMC3150262 DOI: 10.1186/1471-2091-12-32] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 06/27/2011] [Indexed: 01/30/2023]
Abstract
Background Ixodes scapularis, commonly known as the blacklegged or deer tick, is the main vector of Lyme disease in the United States. Recent progress in transcriptome research has uncovered hundreds of different proteins expressed in the salivary glands of hard ticks, the majority of which have no known function, and include many novel protein families. We recently identified transcripts coding for two putative cytosolic sulfotransferases in these ticks which recognized phenolic monoamines as their substrates. In this current study, we characterize the genetic expression of these two cytosolic sulfotransferases throughout the tick life cycle as well as the enzymatic properties of the corresponding recombinant proteins. Interestingly, the resultant recombinant proteins showed sulfotransferase activity against both neurotransmitters dopamine and octopamine. Results The two sulfotransferase genes were coded as Ixosc SULT 1 & 2 and corresponding proteins were referred as Ixosc Sult 1 and 2. Using gene-specific primers, the sulfotransferase transcripts were detected throughout the blacklegged tick life cycle, including eggs, larvae, nymphs, adult salivary glands and adult midgut. Notably, the mRNA and protein levels were altered upon feeding during both the larval and nymphal life stages. Quantitative PCR results confirm that Ixosc SULT1 was statistically increased upon blood feeding while Ixosc SULT 2 was decreased. This altered expression led us to further characterize the function of these proteins in the Ixodid tick. The sulfotransferase genes were cloned and expressed in a bacterial expression system, and purified recombinant proteins Ixosc Sult 1(R) and 2(R) showed sulfotransferase activity against neurotransmitters dopamine and octopamine as well as the common sulfotransferase substrate p-nitrophenol. Thus, dopamine- or octopamine-sulfonation may be involved in altering the biological signal for salivary secretion in I. scapularis. Conclusions Collectively, these results suggest that a function of Ixosc Sult 1 and Sult 2 in Ixodid tick salivary glands may include inactivation of the salivation signal via sulfonation of dopamine or octopamine.
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Affiliation(s)
- Sivakamasundari Pichu
- Center for Vector-Borne Disease, University of Rhode Island, Kingston, RI 02881, USA.
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Schuijt TJ, Narasimhan S, Daffre S, DePonte K, Hovius JWR, Van't Veer C, van der Poll T, Bakhtiari K, Meijers JCM, Boder ET, van Dam AP, Fikrig E. Identification and characterization of Ixodes scapularis antigens that elicit tick immunity using yeast surface display. PLoS One 2011; 6:e15926. [PMID: 21246036 PMCID: PMC3016337 DOI: 10.1371/journal.pone.0015926] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Accepted: 12/02/2010] [Indexed: 11/30/2022] Open
Abstract
Repeated exposure of rabbits and other animals to ticks results in acquired resistance or immunity to subsequent tick bites and is partially elicited by antibodies directed against tick antigens. In this study we demonstrate the utility of a yeast surface display approach to identify tick salivary antigens that react with tick-immune serum. We constructed an Ixodes scapularis nymphal salivary gland yeast surface display library and screened the library with nymph-immune rabbit sera and identified five salivary antigens. Four of these proteins, designated P8, P19, P23 and P32, had a predicted signal sequence. We generated recombinant (r) P8, P19 and P23 in a Drosophila expression system for functional and immunization studies. rP8 showed anti-complement activity and rP23 demonstrated anti-coagulant activity. Ixodes scapularis feeding was significantly impaired when nymphs were fed on rabbits immunized with a cocktail of rP8, rP19 and rP23, a hall mark of tick-immunity. These studies also suggest that these antigens may serve as potential vaccine candidates to thwart tick feeding.
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Affiliation(s)
- Tim J Schuijt
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America.
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Dai J, Narasimhan S, Zhang L, Liu L, Wang P, Fikrig E. Tick histamine release factor is critical for Ixodes scapularis engorgement and transmission of the lyme disease agent. PLoS Pathog 2010; 6:e1001205. [PMID: 21124826 PMCID: PMC2991271 DOI: 10.1371/journal.ppat.1001205] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Accepted: 10/21/2010] [Indexed: 11/19/2022] Open
Abstract
Ticks are distributed worldwide and affect human and animal health by transmitting diverse infectious agents. Effective vaccines against most tick-borne pathogens are not currently available. In this study, we characterized a tick histamine release factor (tHRF) from Ixodes scapularis and addressed the vaccine potential of this antigen in the context of tick engorgement and B. burgdorferi transmission. Results from western blotting and quantitative Reverse Transcription-PCR showed that tHRF is secreted in tick saliva, and upregulated in Borrelia burgdorferi-infected ticks. Further, the expression of tHRF was coincident with the rapid feeding phase of the tick, suggesting a role for tHRF in tick engorgement and concomitantly, for efficient B. burgdorferi transmission. Silencing tHRF by RNA interference (RNAi) significantly impaired tick feeding and decreased B. burgdorferi burden in mice. Interfering with tHRF by actively immunizing mice with recombinant tHRF, or passively transferring tHRF antiserum, also markedly reduced the efficiency of tick feeding and B. burgdorferi burden in mice. Recombinant tHRF was able to bind to host basophils and stimulate histamine release. Therefore, we speculate that tHRF might function in vivo to modulate vascular permeability and increase blood flow to the tick bite-site, facilitating tick engorgement. These findings suggest that blocking tHRF might offer a viable strategy to complement ongoing efforts to develop vaccines to block tick feeding and transmission of tick-borne pathogens.
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Affiliation(s)
- Jianfeng Dai
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sukanya Narasimhan
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Lili Zhang
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Lei Liu
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Penghua Wang
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Erol Fikrig
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
- Howard Hughes Medical Institute, Chevy Chase, Maryland, United States of America
- * E-mail:
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66
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Rodriguez-Valle M, Lew-Tabor A, Gondro C, Moolhuijzen P, Vance M, Guerrero FD, Bellgard M, Jorgensen W. Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and Bos taurus cattle. BMC Genomics 2010; 11:437. [PMID: 20637126 PMCID: PMC3224725 DOI: 10.1186/1471-2164-11-437] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2010] [Accepted: 07/19/2010] [Indexed: 11/23/2022] Open
Abstract
Background Rhipicephalus (Boophilus) microplus is an obligate blood feeder which is host specific to cattle. Existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during the tick - host interaction is poor. Results Global analysis of gene expression changes in whole R. microplus ticks during larval, pre-attachment and early adult stages feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13,601 R. microplus transcripts from BmiGI Version 2 we identified 297 high and 17 low expressed transcripts that were significantly differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman)] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian)] (p ≤ 0.001). These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor, and cuticle formation. Microarrays were validated by qRT-PCR analysis of selected transcripts using three housekeeping genes as normalization controls. Conclusion The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds, particularly Bos indicus cattle. R. microplus ticks demonstrate different transcript expression patterns when they encounter tick resistant and susceptible breeds of cattle. In this study we provide the first transcriptome evidence demonstrating the influence of tick resistant and susceptible cattle breeds on transcript expression patterns and the molecular physiology of ticks during host attachment and feeding. The microarray data used in this analysis have been submitted to NCBI GEO database under accession number GSE20605 http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE20605.
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67
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Dai J, Wang P, Adusumilli S, Booth CJ, Narasimhan S, Anguita J, Fikrig E. Antibodies against a tick protein, Salp15, protect mice from the Lyme disease agent. Cell Host Microbe 2010; 6:482-92. [PMID: 19917502 DOI: 10.1016/j.chom.2009.10.006] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Revised: 08/31/2009] [Accepted: 10/09/2009] [Indexed: 11/24/2022]
Abstract
Traditionally, vaccines directly target a pathogen or microbial toxin. Lyme disease, caused by Borrelia burgdorferi, is a tick-borne illness for which a human vaccine is not currently available. B. burgdorferi binds a tick salivary protein, Salp15, during transmission from the vector, and this interaction facilitates infection of mice. We now show that Salp15 antiserum significantly protected mice from B. burgdorferi infection. Salp15 antiserum also markedly enhanced the protective capacity of antibodies against B. burgdorferi antigens, such as OspA or OspC. Mice actively immunized with Salp15 were also significantly protected from tick-borne Borrelia. In vitro assays showed that Salp15 antiserum increased the clearance of Salp15-coated B. burgdorferi by phagocytes, suggesting a mechanism of action. Vaccination with a vector molecule that a microbe requires for infection of the mammalian host suggests a new strategy for the prevention of Lyme disease, and this paradigm may be applicable to numerous arthropod-borne pathogens of medical importance.
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Affiliation(s)
- Jianfeng Dai
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, CT 06520, USA
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68
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Schuijt TJ, Hovius JW, van der Poll T, van Dam AP, Fikrig E. Lyme borreliosis vaccination: the facts, the challenge, the future. Trends Parasitol 2010; 27:40-7. [PMID: 20594913 DOI: 10.1016/j.pt.2010.06.006] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2010] [Revised: 05/31/2010] [Accepted: 06/02/2010] [Indexed: 11/26/2022]
Abstract
Lyme disease, or Lyme borreliosis, the most prevalent arthropod-borne disease in the Western world, is caused by spirochetes belonging to the Borrelia burgdorferi sensu lato group and is predominantly transmitted through Ixodes ticks. There is currently no vaccine available to prevent Lyme borreliosis in humans. Borrelia outer membrane proteins are reviewed which have been investigated as vaccine candidates. In addition, several tick proteins are discussed, on which anti-tick vaccines have been based, or are interesting future candidates, to prevent transmission of the spirochete from the tick vector to the mammalian host. Finally, novel vaccination strategies to prevent Lyme borreliosis are proposed, based on multiple Borrelia antigens, tick antigens or a combination of both Borrelia as well as tick antigens.
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Affiliation(s)
- T J Schuijt
- Academic Medical Center, University of Amsterdam, Center for Experimental and Molecular Medicine, Amsterdam, The Netherlands
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69
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Xu W, Faisal M. Factorial microarray analysis of zebra mussel (Dreissena polymorpha: Dreissenidae, Bivalvia) adhesion. BMC Genomics 2010; 11:341. [PMID: 20509938 PMCID: PMC2894042 DOI: 10.1186/1471-2164-11-341] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2009] [Accepted: 05/28/2010] [Indexed: 01/24/2023] Open
Abstract
Background The zebra mussel (Dreissena polymorpha) has been well known for its expertise in attaching to substances under the water. Studies in past decades on this underwater adhesion focused on the adhesive protein isolated from the byssogenesis apparatus of the zebra mussel. However, the mechanism of the initiation, maintenance, and determination of the attachment process remains largely unknown. Results In this study, we used a zebra mussel cDNA microarray previously developed in our lab and a factorial analysis to identify the genes that were involved in response to the changes of four factors: temperature (Factor A), current velocity (Factor B), dissolved oxygen (Factor C), and byssogenesis status (Factor D). Twenty probes in the microarray were found to be modified by one of the factors. The transcription products of four selected genes, DPFP-BG20_A01, EGP-BG97/192_B06, EGP-BG13_G05, and NH-BG17_C09 were unique to the zebra mussel foot based on the results of quantitative reverse transcription PCR (qRT-PCR). The expression profiles of these four genes under the attachment and non-attachment were also confirmed by qRT-PCR and the result is accordant to that from microarray assay. The in situ hybridization with the RNA probes of two identified genes DPFP-BG20_A01 and EGP-BG97/192_B06 indicated that both of them were expressed by a type of exocrine gland cell located in the middle part of the zebra mussel foot. Conclusions The results of this study suggested that the changes of D. polymorpha byssogenesis status and the environmental factors can dramatically affect the expression profiles of the genes unique to the foot. It turns out that the factorial design and analysis of the microarray experiment is a reliable method to identify the influence of multiple factors on the expression profiles of the probesets in the microarray; therein it provides a powerful tool to reveal the mechanism of zebra mussel underwater attachment.
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Affiliation(s)
- Wei Xu
- Department of Pathobiology & Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
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70
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Lew-Tabor AE, Moolhuijzen PM, Vance ME, Kurscheid S, Valle MR, Jarrett S, Minchin CM, Jackson LA, Jonsson NN, Bellgard MI, Guerrero FD. Suppressive subtractive hybridization analysis of Rhipicephalus (Boophilus) microplus larval and adult transcript expression during attachment and feeding. Vet Parasitol 2010; 167:304-20. [DOI: 10.1016/j.vetpar.2009.09.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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71
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Havlíková S, Roller L, Koči J, Trimnell AR, Kazimírová M, Klempa B, Nuttall PA. Functional role of 64P, the candidate transmission-blocking vaccine antigen from the tick, Rhipicephalus appendiculatus. Int J Parasitol 2009; 39:1485-94. [DOI: 10.1016/j.ijpara.2009.05.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2009] [Revised: 05/01/2009] [Accepted: 05/04/2009] [Indexed: 11/17/2022]
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72
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Bagnall N, Gough J, Cadogan L, Burns B, Kongsuwan K. Expression of intracellular calcium signalling genes in cattle skin during tick infestation. Parasite Immunol 2009; 31:177-87. [PMID: 19292769 DOI: 10.1111/j.1365-3024.2008.01092.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
It is widely acknowledged that changes in intracellular calcium ion (Ca(2+)) concentration provide dynamic signals that control a plethora of cellular processes, including triggering and mediating host defence mechanisms. In this study, quantitative real-time PCR was used to analyse gene expression of 14 Ca(2+) signalling proteins in skin obtained from high tick-resistant (HR) and low tick-resistant (LR) cattle following artificial challenge with cattle tick (Rhipicephalus (Boophilus) microplus). Up-regulation of numerous genes was observed in both HR and LR skin following tick challenge, however substantially higher transcription activation was found in HR tissue. The elevated expression in HR skin of specific Ca(2+) signalling genes such as AHNAK, CASQ, IL2, NFAT2CIP and PLCG1 may be related to host resistance. Our data suggest that Ca(2+) and its associated proteins might play an important role in host response to ticks and that further investigation is warranted.
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Affiliation(s)
- N Bagnall
- CSIRO Livestock Industries, Queensland Bioscience Precinct, St Lucia QLD, Australia
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Abstract
The saliva of hematophagous arthropods contains potent anti-inflammatory and antihemostatic activities that promote acquisition of the blood meal and enhance infection with pathogens. We have shown that polymorphonuclear leukocytes (PMN) treated with the saliva of the tick Ixodes scapularis have reduced expression of beta(2) integrins, impaired PMN adherence, and reduced killing of Borrelia burgdorferi, the causative agent of Lyme disease. Here we describe two Ixodes proteins that are induced upon tick feeding and expressed predominantly in the salivary glands. Using saliva harvested from ticks with reduced levels of ISL 929 and ISL 1373 through targeted RNA interference knockdown, as well as purified recombinant proteins, we show the effects of these proteins on downregulation of PMN integrins and inhibition of the production of O(2)(-) by PMN in vitro. Mice immunized with ISL 929/1373 had increased numbers of PMN at the site of tick attachment and a lower spirochete burden in the skin and joints 21 days after infection compared to control-immunized animals. Our results suggest that ISL 929 and ISL 1373 contribute to the inhibition of PMN functions shown previously with tick saliva and support important roles for these inhibitory proteins in the modulation of PMN function in vivo.
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Development of a cDNA microarray of zebra mussel (Dreissena polymorpha) foot and its use in understanding the early stage of underwater adhesion. Gene 2009; 436:71-80. [PMID: 19393183 DOI: 10.1016/j.gene.2009.01.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2008] [Revised: 12/20/2008] [Accepted: 01/05/2009] [Indexed: 11/21/2022]
Abstract
The underwater adhesion of the zebra mussel (Dreissena polymorpha) to substrates is a complex process that is controlled by a delicate apparatus, the byssus. As a critical activity of the byssus glands embedded in the zebra mussel feet, byssogenesis is highly active to produce numerous byssal threads from the settled juvenile stage through the adult stage in its life cycle. This lifelong activity helps the zebra mussel to firmly attach to substrata underwater, thereby causing severe economic and ecologic impacts. In an attempt to better understand the zebra mussel's byssus activity, a cDNA microarray (ZMB) including 716 genes, generated from a Suppression Subtractive Hybridization (SSH) cDNA library, was printed and used for the comparison of gene expression during zebra mussel adhesion and non-adhesion. To better understand the byssogenesis mechanism, RNA samples from the zebra mussel feet with byssogenesis and without byssogenesis were used in a two-color hybridization to reveal the gene differential expression in the two states. Based on the P values (P<0.05), Fifty-two ESTs were found as differentially expressed genes and were divided into two groups, upregulated and downregulated groups according to there logFC values. With the false discovery rate (FDR) adjustment, seven were identified from the upregulated group and nine from the downregulated group. Phylogenetic analysis indicated that the four excretory gland peptide-like protein (EGP) encoding genes in upregulated group are structurally different than the two in the downregulated list. The amino acid composition analysis on the proteins, which were encoded by the up- or downregulated ESTs without homologues (NH) suggested that seven of the NH proteins are biochemically similar to the novel foot proteins from other mussels. The quantitative reverse transcription PCR (QRT-PCR) proved the uniqueness of the templates in the array, and also confirmed the differentially expressed genes identified by microarray experiment. Our findings demonstrated that the zebra mussel byssus cDNA microarray is an efficient tool for the studies of differential gene expression in different byssogenesis states, thereby revealing important details of the underwater adhesion.
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75
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Tick saliva affects both proliferation and distribution of Borrelia burgdorferi spirochetes in mouse organs and increases transmission of spirochetes to ticks. Int J Med Microbiol 2009; 299:373-80. [PMID: 19147403 DOI: 10.1016/j.ijmm.2008.10.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2008] [Revised: 10/22/2008] [Accepted: 10/25/2008] [Indexed: 11/21/2022] Open
Abstract
Ixodes ricinus tick saliva-activated transmission of Borrelia burgdorferi sensu stricto spirochetes was studied on the C3H/HeN mouse model. The influence of the feeding of uninfected nymphs on the proliferation and distribution of intradermally inoculated spirochetes was compared with the effect of co-inoculated saliva or salivary gland extract (SGE), respectively. Spirochete loads in murine tissues were evaluated using real-time q-PCR. SGE induced significantly increased spirochete numbers in the skin on the days 4 and 6 post-infection (p.i.). On the other hand, decreased bacterial load in the heart of SGE-treated mice was demonstrated in comparison with control animals. The inoculation of tick saliva increased spirochete load in the urinary bladder on day 6 p.i., while the number of spirochetes in the heart declined on day 6 p.i. The feeding of I. ricinus nymphs raised the spirochete load in the bladder on the days 4 and 6 p.i. On day 6, the number of spirochetes found in the heart was significantly lower than in controls. The prevalence of spirochetes in ticks infected by feeding on mice was more than 10 times higher when the mice were infected with the mixture of spirochetes and saliva or SGE, in comparison with spirochetes alone. The presence of SGE in the infectious inoculum increased the spirochete burden per tick from 0 to almost 28,000. Taken together, these results show a very early effect of tick saliva on the proliferation and distribution of Borrelia spirochetes in the host, probably due to the effect of saliva on the host innate immunity mechanisms.
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76
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Juncadella IJ, Anguita J. The immunosuppresive tick salivary protein, Salp15. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 666:121-31. [PMID: 20054980 DOI: 10.1007/978-1-4419-1601-3_10] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The interaction between Ixodid ticks and their mammalian hosts is a complex relationship. While the mammalian host tries to avoid the completion of the feeding process, the tick has devised strategies to counteract these attempts. Tick saliva contains a vast array of pharmacological activities that presumably aid the tick to evade host responses, including anticomplement, oxidative and innate and adaptive immune responses. The characterization of these activities has gained momentum in the last several years. One of the best studied activities present in tick saliva corresponds to the antigen known as Salp15, which binds specifically to the T-cell coreceptor CD4 resulting in the specific repression of CD4+ T-cell activation. We discuss here the current state of our knowledge of the mode of action of this salivary protein.
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Affiliation(s)
- Ignacio J Juncadella
- Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
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Peterková K, Vancová I, Hajnická V, Slovák M, Simo L, Nuttall PA. Immunomodulatory arsenal of nymphal ticks. MEDICAL AND VETERINARY ENTOMOLOGY 2008; 22:167-171. [PMID: 18498617 DOI: 10.1111/j.1365-2915.2008.00726.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ticks have developed their own immunomodulatory mechanisms to inhibit the host inflammatory response. One of them involves the ability to subvert the cytokine network at the site of tick feeding by secreting cytokine binding molecules. Most studies have focused on the immunomodulatory prowess of adult female ticks. Here we describe anti-cytokine activity in salivary gland extracts (SGEs) prepared from 2-day-fed nymphs of Dermacentor reticulatus Fabricius, Ixodes ricinus L., Rhipicephalus appendiculatus Neumann and Amblyomma variegatum Fabricius. Anti-CXCL8 activity was detected in nymphs of all species. Relatively high activity against CCL2, CCL3 and CCL11 was observed in SGEs of R. appendiculatus and A. variegatum nymphs, whereas SGEs of I. ricinus nymphs showed comparatively high anti-interleukin-2 (-IL-2) and anti-IL-4 activities. These data show that nymphs, which epidemiologically are usually more important than adults as disease vectors, possess a range of anti-cytokine activities that may facilitate pathogen transmission.
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Affiliation(s)
- K Peterková
- Institute of Virology, Slovak Academy of Sciences, Bratislava, Slovakia
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78
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In vitro splenocyte proliferation responses of BALB/c mice to salivary gland extracts of three ixodid tick species (Acari: Ixodidae). Biologia (Bratisl) 2007. [DOI: 10.2478/s11756-007-0141-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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