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Biological Sciences Faculty Publications

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Articles 61 - 87 of 87

Full-Text Articles in Immunology and Infectious Disease

Single-Tube Real-Time Pcr Assay For Differentiation Of Ixodes Affinis And Ixodes Scapularis, Chelsea L. Wright, Wayne L. Hynes, Breanna T. White, Mindy N. Marshall, Holly D. Gaff, David T. Gauthier Jan 2014

Single-Tube Real-Time Pcr Assay For Differentiation Of Ixodes Affinis And Ixodes Scapularis, Chelsea L. Wright, Wayne L. Hynes, Breanna T. White, Mindy N. Marshall, Holly D. Gaff, David T. Gauthier

Biological Sciences Faculty Publications

Ixodes affinis Neumann (1899) and Ixodes scapularis Say (1821) are tick vectors of the etiologic agent of Lyme disease, Borrelia burgdorferi sensu stricto. Ixodes affinis and I. scapularis are morphologically very similar, and as they are sympatric in the mid- and south-Atlantic U.S. coastal states, their accurate identification is crucial to studies of disease and vector ecology in this area. This work describes a rapid, single-tube SYBR® Green-based real-time PCR assay for differentiation of I. affinis and I. scapularis at all life stages. The assay employs 2 pairs of species specific primers directed against the internal transcribed spacer 2 (ITS2) …

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The Role Of P38 Mapk In The Aetiopathogenesis Of Psoriasis And Psoriatic Arthritis, Athanasios Mavropoulos, Eirini I. Rigopoulou, Christos Liaskos, Dimitrios P. Bogdanos, Lazaros I. Sakkas Jan 2013

The Role Of P38 Mapk In The Aetiopathogenesis Of Psoriasis And Psoriatic Arthritis, Athanasios Mavropoulos, Eirini I. Rigopoulou, Christos Liaskos, Dimitrios P. Bogdanos, Lazaros I. Sakkas

Biological Sciences Faculty Publications

The pathogenetic mechanisms responsible for the induction of immune-mediated disorders, such as psoriasis, remain not well characterized. Molecular signaling pathways are not well described in psoriasis, as well as psoriatic arthritis, which is seen in up to 40% of patients with psoriasis. Signaling pathway defects have long been hypothesized to participate in the pathology of psoriasis, yet their implication in the altered psoriatic gene expression still remains unclear. Emerging data suggest a potential pathogenic role for mitogen activated protein kinases p38 (p38 MAPK) extracellular signal-regulated kinase 1/2 (ERK1/2), and c-Jun N-terminal kinase (JNK) in the development of psoriasis. The data …

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In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards Jan 2012

In Vitro Propagation Of Candidatus Rickettsia Andeanae Isolated From Amblyomma Maculatum, Alison Luce-Fedrow, Chelsea Wright, Holly D. Gaff, Daniel E. Sonenshine, Wayne L. Hynes, Allen L. Richards

Biological Sciences Faculty Publications

Candidatus Rickettsia andeanae was identified during an investigation of a febrile outbreak in northwestern Peru (2002). DNA sequencing from two ticks (Amblyomma maculatum, Ixodes boliviensis) collected during the investigation revealed a novel Rickettsia agent with similarity to the spotted fever group rickettsiae. Since then, Candidatus R. similar to andeanae has been detected in A. maculatum ticks collected in the southeastern and southcentral United States, Argentina, and Peru. To date, Candidatus R. andeanae has not been successfully cultivated in the laboratory. We present evidence for the continuous cultivation in three cell lines of Candidatus R. similar to …

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The Fecal Viral Flora Of Wild Rodents, Tung G. Phan, Beatrix Kapusinszky, Chunlin Wang, Robert K. Rose, Howard L. Lipton, Eric L. Delwart Sep 2011

The Fecal Viral Flora Of Wild Rodents, Tung G. Phan, Beatrix Kapusinszky, Chunlin Wang, Robert K. Rose, Howard L. Lipton, Eric L. Delwart

Biological Sciences Faculty Publications

The frequent interactions of rodents with humans make them a common source of zoonotic infections. To obtain an initial unbiased measure of the viral diversity in the enteric tract of wild rodents we sequenced partially purified, randomly amplified viral RNA and DNA in the feces of 105 wild rodents (mouse, vole, and rat) collected in California and Virginia. We identified in decreasing frequency sequences related to the mammalian viruses families Circoviridae, Picobirnaviridae, Picornaviridae, Astroviridae, Parvoviridae, Papillomaviridae, Adenoviridae, and Coronaviridae. Seventeen small circular DNA genomes containing one or two replicase genes distantly related to the Circoviridae representing several potentially …

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Rickettsia Parkeri In Gulf Coast Ticks, Southeastern Virginia, Usa, Chelsea L. Wright, Robyn M. Nadolny, Ju Jiang, Allen L. Richards, Daniel E. Sonenshine, Holly D. Gaff, Wayne L. Hynes May 2011

Rickettsia Parkeri In Gulf Coast Ticks, Southeastern Virginia, Usa, Chelsea L. Wright, Robyn M. Nadolny, Ju Jiang, Allen L. Richards, Daniel E. Sonenshine, Holly D. Gaff, Wayne L. Hynes

Biological Sciences Faculty Publications

We report evidence that Amblyomma maculatum tick populations are well established in southeastern Virginia. We found that 43.1% of the adult Gulf Coast ticks collected in the summer of 2010 carried Rickettsia parkeri, suggesting that persons living in or visiting southeastern Virginia are at risk for infection with this pathogen.

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Estimating The Impact Of Human Papillomavirus (Hpv) Vaccination On Hpv Prevalence And Cervical Cancer Incidence In Mali, Leree Tracy, Holly Gaff, Colleen Burgess, Samba Sow, Patti E. Gravitt, J. Kathleen Tracy Jan 2011

Estimating The Impact Of Human Papillomavirus (Hpv) Vaccination On Hpv Prevalence And Cervical Cancer Incidence In Mali, Leree Tracy, Holly Gaff, Colleen Burgess, Samba Sow, Patti E. Gravitt, J. Kathleen Tracy

Biological Sciences Faculty Publications

Human papillomavirus vaccines have potential to reduce cervical cancer incidence and mortality; however, cultural and economic barriers may hinder success in developing countries. We assessed impact of a single vaccine campaign in Mali with use of mathematical modeling. Our model shows that decreases in the prevalence of Human papillomavirus infection are proportional to achieved vaccination coverage.

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Estimating The Reproductive Numbers For The 2008-2009 Cholera Outbreaks In Zimbabwe, Zindoga Mukandavire, Shu Liao, Jin Wang, Holly Gaff, David L. Smith, J. Glenn Morris Jr. Jan 2011

Estimating The Reproductive Numbers For The 2008-2009 Cholera Outbreaks In Zimbabwe, Zindoga Mukandavire, Shu Liao, Jin Wang, Holly Gaff, David L. Smith, J. Glenn Morris Jr.

Biological Sciences Faculty Publications

Cholera remains an important global cause of morbidity and mortality, capable of causing periodic epidemic disease. Beginning in August 2008, a major cholera epidemic occurred in Zimbabwe, with 98,585 reported cases and 4,287 deaths. The dynamics of such outbreaks, particularly in nonestuarine regions, are not well understood. We explored the utility of mathematical models in understanding transmission dynamics of cholera and in assessing the magnitude of interventions necessary to control epidemic disease. Weekly data on reported cholera cases were obtained from the Zimbabwe Ministry of Health and Child Welfare (MoHCW) for the period from November 13, 2008 to July 31, …

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Distinct Macrophage Subpopulations Regulate Viral Encephalitis But Not Viral Clearance In The Cns, Christina D. Steel, Woong-Ki Kim, Larry Sanford, Laurie Wellman, Sandra Burnett, Nico Van Rooijen, Rochard P. Ciavarra Sep 2010

Distinct Macrophage Subpopulations Regulate Viral Encephalitis But Not Viral Clearance In The Cns, Christina D. Steel, Woong-Ki Kim, Larry Sanford, Laurie Wellman, Sandra Burnett, Nico Van Rooijen, Rochard P. Ciavarra

Biological Sciences Faculty Publications

Intranasal application of vesicular stomatitis virus (VSV) induces acute encephalitis characterized by a pronounced myeloid and T cell infiltrate. The role of distinct phagocytic populations on VSV encephalitis was therefore examined in this study. Ablation of peripheral macrophages did not impair VSV encephalitis or viral clearance from the brain, whereas, depletion of splenic marginal dendritic cells impaired this response and enhanced morbidity/mortality. Selective depletion of brain perivascular macrophages also suppressed this response without altering viral clearance. Thus, two anatomically distinct phagocytic populations regulate VSV encephalitis in a non-redundant fashion although neither population is essential for viral clearance in the CNS. …

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Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, John C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig Jan 2010

Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, John C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig

Biological Sciences Faculty Publications

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT) are major determinants of verapamil (VP)-reversible CQ resistance (CQR). In the presence of mutant PfCRT, additional genes contribute to the wide range of CQ susceptibilities observed. It is not known if these genes influence mechanisms of chemosensitization by CQR reversal agents. Using quantitative trait locus (QTL) mapping of progeny clones from the HB3 x Dd2 cross, we show that the P. falciparum multidrug resistance gene 1 (pfmdr1) interacts with the South-East Asia-derived mutant pfcrt haplotype to modulate CQR levels. A novel chromosome 7 locus is predicted to contribute …

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A Review Of The Lethal Spiny Lobster Virus Pav1 - Ten Years After Its Discovery, Donald C. Behringer, Mark J. Butler Iv, Jeffrey D. Shields Nov 2009

A Review Of The Lethal Spiny Lobster Virus Pav1 - Ten Years After Its Discovery, Donald C. Behringer, Mark J. Butler Iv, Jeffrey D. Shields

Biological Sciences Faculty Publications

In 1999, we discovered that juvenile Caribbean spiny lobsters (Panulirus argus) in the Florida Keys were infected with PaV1 (Panulirus argus virus 1), the first naturally occurring pathogenic virus reported from lobsters. The virus profoundly affects their biology and ecology. PaV1 is probably wide-spread in the Caribbean with confirmed infections from the United States (Florida), St Croix, Mexico, and Belize; and anecdotal reports from the Bahamas and Cuba. Mean prevalence in the Florida Keys has been stable since 1999 (5 - 8%), but has risen from 2.7% to 10.9% in Mexico (Puerto Morelos), the only other country where …

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Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes Jan 2008

Molecular Characterization And Related Aspects Of The Innate Immune Response In Ticks, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Compared to insects, little is known about innate immunity in ticks. This chapter addresses the molecular processes that recognize non-self and the cellular and molecular processes mobilized to phagocytose, engulf, inhibit or kill invaders. We discuss the receptors that recognize pathogen associated molecular patterns (PAMPs) and the putative up-regulation of regulatory cascades that lead, ultimately, to cellular or molecular responses. We describe the molecular events that activate the cellular processes and the array of humoral factors that are mobilized against invading organisms, including antimicrobial peptides, proteases and protease inhibitors, lectins, coagulation factors and others. Special attention is directed to the …

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Using Rna Interference To Determine The Role Of Varisin In The Innate Immune System Of The Hard Tick Dermacentor Variabilis (Acari: Ixodidae)., Wayne L. Hynes, Martha M. Stokes, Shannon M. Hensley, S. Michelle Todd, Daniel E. Sonenshine Jan 2008

Using Rna Interference To Determine The Role Of Varisin In The Innate Immune System Of The Hard Tick Dermacentor Variabilis (Acari: Ixodidae)., Wayne L. Hynes, Martha M. Stokes, Shannon M. Hensley, S. Michelle Todd, Daniel E. Sonenshine

Biological Sciences Faculty Publications

Defensins are an important component of the innate immune system of ticks. These small peptides are produced by various genera of ticks, and expressed in various tissues. In this study we used RNA interference to silence the expression of the defensin varisin produced by the hemocytes of the American dog tick, Dermacentor variabilis. Ticks were injected with double stranded varisin RNA prior to being placed on a rabbit. After feeding, the ticks were removed, bled, and the hemolymph plasma and hemocytes separated. Hemocytes were screened for the presence (or absence) of both varisin transcript and peptide. Varisin peptide was …

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Historical Mammal Extinction On Christmas Island (Indian Ocean) Correlates With Introduced Infectious Disease, Kelly B. Wyatt, Paula F. Campos, M. Thomas P. Gilbert, Sergios-Orestis Kolokotronis, Wayne H. Hynes, Rob Desalle, Peter Daszak, Ross D.E. Macphee, Alex D. Greenwood Jan 2008

Historical Mammal Extinction On Christmas Island (Indian Ocean) Correlates With Introduced Infectious Disease, Kelly B. Wyatt, Paula F. Campos, M. Thomas P. Gilbert, Sergios-Orestis Kolokotronis, Wayne H. Hynes, Rob Desalle, Peter Daszak, Ross D.E. Macphee, Alex D. Greenwood

Biological Sciences Faculty Publications

It is now widely accepted that novel infectious disease can be a leading cause of serious population decline and even outright extinction in some invertebrate and vertebrate groups (e. g., amphibians). In the case of mammals, however, there are still no well-corroborated instances of such diseases having caused or significantly contributed to the complete collapse of species. A case in point is the extinction of the endemic Christmas Island rat (Rattus macleari): although it has been argued that its disappearance ca. AD 1900 may have been partly or wholly caused by a pathogenic trypanosome carried by fleas hosted …

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Silencing Expression Of The Defensin, Varisin, In Male Dermacentor Variabilis By Rna Interference Results In Reduced Anaplasma Marginale Infections, Katherine M. Kocan, Jose De La Fuente, Raul Manzano-Roman, Victoria Naranjo, Wayne L. Hynes, Daniel E. Sonenshine Jan 2008

Silencing Expression Of The Defensin, Varisin, In Male Dermacentor Variabilis By Rna Interference Results In Reduced Anaplasma Marginale Infections, Katherine M. Kocan, Jose De La Fuente, Raul Manzano-Roman, Victoria Naranjo, Wayne L. Hynes, Daniel E. Sonenshine

Biological Sciences Faculty Publications

Antimicrobial peptides, including defensins, are components of the innate immune system in ticks that have been shown to provide protection against both gram-negative and gram-positive bacteria. Varisin, one of the defensins identified in Dermacentor variabilis, was shown to be produced primarily in hemocytes but transcript levels were also expressed in midguts and other tick cells. In this research, we studied the role of varisin in the immunity of ticks to the gram-negative cattle pathogen, Anaplasma marginale. Expression of the varisin gene was silenced by RNA interference (RNAi) in which male ticks were injected with varisin dsRNA and then …

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Sequence And The Developmental And Tissue-Specific Regulation Of The First Complete Vitellogenin Message From Ticks, Deborah M. Thompson, Sayed M.S. Khalil, Laura A. Jeffers, Daniel E. Sonenshine, Robert D. Mitchell, Christopher J. Osgood, R. Michael Roe Jan 2007

Sequence And The Developmental And Tissue-Specific Regulation Of The First Complete Vitellogenin Message From Ticks, Deborah M. Thompson, Sayed M.S. Khalil, Laura A. Jeffers, Daniel E. Sonenshine, Robert D. Mitchell, Christopher J. Osgood, R. Michael Roe

Biological Sciences Faculty Publications

The first full-length mRNA for vitellogenin (Vg) from ticks was sequenced. This also represents the first complete sequence of Vg from the Chelicerata and of a heme binding Vg. The Vg cDNA from the American dog tick, Dermacentor variabilis was 5744nt in length (GenBank Accession number AY885250), which coded for a protein of 1843aa with a calculated molecular weight of 208kD. This protein had an 18 aa signal sequence, a single RXXR cleavage signal that would generate two subunits (49.5 and 157K in molecular weight) and lipoprotein N-terminal and carboxy von Willebrand factor type D domains. Tryptic digest MS analysis …

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Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe Jan 2007

Design, Synthesis, And Evaluation Of 10-N-Substituted Acridones As Novel Chemosensitizers In Plasmodium Falciparum, Jane X. Kelly, Martin J. Smilkstein, Roland A. Cooper, Kristin D. Lane, Robert A. Johnson, Aaron Janowsky, Rozalia A. Dodean, David J. Hinrichs, Rolf Winter, Michael Riscoe

Biological Sciences Faculty Publications

A series of novel 10-N-substituted acridones, bearing alkyl side chains with tertiary amine groups at the terminal position, were designed, synthesized, and evaluated for the ability to enhance the potency of quinoline drugs against multidrug-resistant (MDR) Plasmodium falciparum malaria parasites. A number of acridone derivatives, with side chains bridged three or more carbon atoms apart between the ring nitrogen and terminal nitrogen, demonstrated chloroquine (CQ)-chemosensitizing activity against the MDR strain of P. falciparum (Dd2). Isobolograrn analysis revealed that selected candidates demonstrated significant synergy with CQ in the CQ-resistant (CQR) parasite Dd2 but only additive (or indifferent) interaction in the CQ-sensitive …

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Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes Jan 2007

Tissue And Life Stage Distribution Of A Defensin-Like Gene In The Lone Star Tick Amblyomma Americanum, S. Michelle Todd, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

The transcript sequence of the Amblyomma americanum Linnaeus (Acari: Ixodidae) defensin, termed amercin (amn), was ascertained and a 219-bp amn coding region identified. The gene encodes a 72-amino acid prepropeptide with a putative 37-amino acid mature peptide. This gene shows little similarity to either of the defensins from Amblyomma hebraeum Koch, the only other Amblyomma species for which a defensin has been described. Sequence comparisons with other tick defensins reveal amn to be shorter (6 bp or 2 amino acids) than the Ixodes scapularis Linnaeus (Acari: Ixodidae) and Dermacentor variabilis (Say) (Acari: Ixodidae) defensin sequences. The amercin prepropeptide …

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A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine Jan 2005

A Defensin-Like Gene Expressed In The Black-Legged Tick, Ixodes Scapularis (Acari: Ixodidae), Wayne L. Hynes, S. M. Ceraul, S. M. Todd, K. C. Seguin, Daniel E. Sonenshine

Biological Sciences Faculty Publications

The black-legged tick Ixodes scapularis linnaeus (Acari: Ixodidae) is an important vector of microbial pathogens. Knowledge of the tick's innate immune response, particularly defensin and other antimicrobial peptides, is important for understanding how microbes survive in this tick. A defensin gene (slnA) from I. scapularis was obtained by reverse transcription-polymerase chain reaction (RT-PCR) using mRNA extracted from tissues of female ticks. RT-PCR indicated the gene was expressed in the midgut, haemocytes, and fat-body, although no evidence of a peptide was found. Sequencing a cloned cDNA fragment revealed a 225 bp open reading frame encoding a 74 amino acid pre-prodefensin, including …

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Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd Jan 2005

Defensin In Ticks: Molecular Characterization, Expression, And Role In Innate Immunity, Daniel E. Sonenshine, Wayne L. Hynes, Shane M. Ceraul, Michelle Todd

Biological Sciences Faculty Publications

No abstract provided.

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An Arthropod Defensin Expressed By The Hemocytes Of The American Dog Tick, Dermacentor Variabilis (Acari: Ixodidae), Shane M. Ceraul, Daniel E. Sonenshine, Robert E. Ratzlaff, Wayne L. Hynes Jan 2003

An Arthropod Defensin Expressed By The Hemocytes Of The American Dog Tick, Dermacentor Variabilis (Acari: Ixodidae), Shane M. Ceraul, Daniel E. Sonenshine, Robert E. Ratzlaff, Wayne L. Hynes

Biological Sciences Faculty Publications

Both soluble and cell-mediated components are involved in the innate immune response of arthropods. Injection of Borrelia burgdorferi, the Lyme disease agent, results in the secretion of defensin into the hemolymph of the ixodid tick, Dermacentor variabilis. The presence of the peptide is observed as early as 15 min post-challenge and remains present through 18 h post-challenge. As observed in insects and soft ticks, the transcript for defensin is detected as early as 1 h post-challenge in D. variabilis. RT-PCR resulted in an amplicon of 624 bp with a 225 bp region that translates to a 74 …

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Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva Jan 2002

Glass Capillary Tube Feeding: A Method For Infecting Nymphal Ixodes Scapularis (Acari: Ixodidae) With The Lyme Disease Spirochete Borrelia Burgdorferi, Anne H. Broadwater, Daniel E. Sonenshine, Wayne L. Hynes, Shane Ceraul, Aravinda M. De Silva

Biological Sciences Faculty Publications

We evaluated an artificial capillary feeding method to infect nymphal Ixodes scapularis (Say) ticks with Borrelia burgdorferi, the causative agent of Lyme disease. Thirty to 70% of the nymphs were infected after feeding for 2.5 h from glass capillary tubes filled with a solution of spirochetes. Capillary infection was stable and persisted in the nymphs for at least 10 d after feeding. Capillary feeding also maintained natural vector competence patterns because I. scapularis ticks acquired infection unlike Dermacentor variablis (Say), which did not become infected. Capillary infected I. scapularis nymphs were capable of transmitting the infection to naive mice …

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Resistance Of The Tick Dermacentor Variabilis (Acari: Ixodidae) Following Challenge With The Bacterium Escherichia Coli (Enterobacteriales: Enterobacteriaceae), Shane M. Ceraul, Daniel E. Sonenshine, Wayne L. Hynes Jan 2002

Resistance Of The Tick Dermacentor Variabilis (Acari: Ixodidae) Following Challenge With The Bacterium Escherichia Coli (Enterobacteriales: Enterobacteriaceae), Shane M. Ceraul, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

In addition to a soluble response, many invertebrates control bacterial infections by means of phagocytosis or melanotic encapsulation. In some insects, Escherichia coli growth is reported to be inhibited by aggregation/encapsulation. Soluble and phagocytic responses to bacterial challenge have been reported in ticks, but evidence of an aggregation/encapsulation response was reported only for inanimate (araldite) implants. Ticks were challenged by direct inoculation of bacteria into the hemocoel cavity. By plating, no viable E. coli were detected 6 h postinoculation. A direct fluorescence assay (DFA) revealed aggregated bacteria 1 h postinoculation. Furthermore, DFA showed aggregated bacteria at 6, 24, and 48 …

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Infection And Transovarial Transmission Of Rickettsiae In Dermacentor Variabilis Acquired By Artificial Feeding, K. R. Macaluso, Daniel E. Sonenshine, Shane M. Ceraul, A. F. Azad Jan 2001

Infection And Transovarial Transmission Of Rickettsiae In Dermacentor Variabilis Acquired By Artificial Feeding, K. R. Macaluso, Daniel E. Sonenshine, Shane M. Ceraul, A. F. Azad

Biological Sciences Faculty Publications

In this study we examined the efficiency of an in vitro feeding technique using glass microcapillaries as a method of establishing rickettsiae-infected lines of ticks. To quantify the volume ingested by ticks during microcapillary feeding, the incorporation of radiolabeled amino acids in tick gut and hemolymph was calculated. Fifteen of 18 ticks consumed between 0.06 μl and 6.77μl. However, ingestion of fluid was not correlated to weight gain during capillary feeding. Uninfected and partially fed laboratory-reared female Dermacentor variabilis ticks were exposed to either Rickettsia montana- or Rickettsia rhipicephali-infected Vero cells via microcapillary tubes, returned to rabbit hosts, …

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Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes Jan 2001

Tick Immunity To Microbial Infections: Control Of Representative Bacteria In The Hard Tick Dermacentor Variabilis (Acari: Ixodidae), Robert Johns, Shane Ceraul, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

No abstract provided.

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Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes Jan 2001

Identification Of A Defensin From The Hemolymph Of The American Dog Tick, Dermacentor Variabilis, Robert Johns, Daniel E. Sonenshine, Wayne L. Hynes

Biological Sciences Faculty Publications

Hemolymph from partially fed virgin Dermacentor variabilis females was collected following Borrelia burgdorferi challenge and assayed for antimicrobial activity against Bacillus subtilis and B. burgdorferi. A small inducible cationic peptide was identified by SDS-PAGE in the hemolymph of these ticks as early as 1h post challenge. Following purification by a three-step procedure involving sequential SepPak elution, reversed phase high performance liquid chromatography (RP-HPLC) and gel electrophoresis, the yield of the active peptide was approximately 0.1% of the total protein in the hemolymph plasma. The molecular weight, 4.2kDa, was determined by MALDI-TOF mass spectrometry. N-terminal sequencing by the Edman degradation …

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Contrasts In Tick Innate Immune Responses To Borrelia Burgdorferi Challenge: Immuno-Tolerance In Ixodes Scapularis Versus Immunocompetence In Dermacentor Variabilis (Acari: Ixodidae)., Robert Johns, Jun Ohnishi, Anne Broadwater, Daniel E. Sonenshine, Aravinda M. Desilva, Wayne L. Hynes Jan 2001

Contrasts In Tick Innate Immune Responses To Borrelia Burgdorferi Challenge: Immuno-Tolerance In Ixodes Scapularis Versus Immunocompetence In Dermacentor Variabilis (Acari: Ixodidae)., Robert Johns, Jun Ohnishi, Anne Broadwater, Daniel E. Sonenshine, Aravinda M. Desilva, Wayne L. Hynes

Biological Sciences Faculty Publications

The blacklegged tick, Ixodes scapularis Say, transmits the Lyme disease spirochete (Borrelia burgdorferi), whereas the American dog tick, Dermacentor variabilis (Say), is unable to transmit the bacterium. We compared the innate immune response of these ticks against spirochetes directly inoculated into the hemocoel cavity of ticks. In I. scapularis, some Borrelia were found associated with hemocytes, while numerous other spiral-shaped, intact bacteria remained free in the hemolymph. In contrast, in D. variabilis only remnants of the bacteria were evident in the hemolymph, indicating lysis; intact spirochetes were rare. Spirochetes were observed bound to or within the organs …

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Absence Of Insect Juvenile Hormones In The American Dog Tick, Dermacentor Veriabilis (Say) (Acari: Ixodidae), And In Ornithodoros Parkeri Cooley (Acari: Argasidae), P. A. Neese, Daniel E. Sonenshine, V. L. Kallapur, C. S. Apperson, R. M. Roe Jan 2000

Absence Of Insect Juvenile Hormones In The American Dog Tick, Dermacentor Veriabilis (Say) (Acari: Ixodidae), And In Ornithodoros Parkeri Cooley (Acari: Argasidae), P. A. Neese, Daniel E. Sonenshine, V. L. Kallapur, C. S. Apperson, R. M. Roe

Biological Sciences Faculty Publications

Synganglia, salivary gland, midgut, ovary, fat body and muscle alone and in combination from the ixodid tick, Dermacentor variabilis (Say), or the argasid tick, Ornithodoros parkeri Cooley, were incubated in vitro in separate experiments with L-[methyl-3H]methionine and farnesoic acid or with [1-14C]acetate. Life stages examined in D. variabilis were 3 and 72 h old (after ecdysis) unfed nymphs, partially fed nymphs (18 and 72 h after attachment to the host), fully engorged nymphs (2 d after detachment from host), 3 and 72 h old (after eclosion) unfed females, partially fed unmated females (12–168 …

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