Immunology and Infectious Disease Commons^™

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 …

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 …

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 …

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 …

The Plasmodium Falciparum Chloroquine Resistance Transporter, Pfcrt, Mediates The Activity Of Chloroquine-Resistance Reversal Agents In The Malaria Parasite, Kristin Lane

Biological Sciences Theses & Dissertations

Chloroquine (CQ) resistant Plasmodium falciparum is a serious problem affecting 3.2 billion people in over 100 countries today. Most endemic malarious countries are among the poorest in the world and lack the resources to replace the inexpensive and highly effective CQ. CQ resistance (CQR) reversal agents are a potentially inexpensive solution to restoring CQ efficacy. CQR reversal agents are drugs that have little to no antimalarial activity alone, but in combination with CQ, they increase dmg accumulation in the parasite and enhance the sensitivity to CQ in CQR parasites. PfCRT is a putative transporter located on the parasite digestive vacuole …

Down-Regulation Of Natural Killer Cell Activation In Response To Influenza Virus In Older Adults, Yu Jing

Theses and Dissertations in Biomedical Sciences

Immune senescence contributes to influenza-associated high mortality and morbidity and reduced vaccine efficacy in elderly people. Type I T cell (Thl)-mediated immunity plays a significant role in Immune responses to influenza infection and vaccination. Natural killer (NK) cells secrete significant amount of IFN-7 , a hallmark Thl cytokine, in response to influenza infection. How aging influences human NK cell IFN-7 production in response to influenza virus has not been well documented. In this study we employed human peripheral blood mononuclear cells (PBMC) and performed intracellular cytokine staining and flow cytometry primarily to investigate how aging influences NK cell activation with …

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 …

On A Multinational Assessment Of Rotavirus Disease In Europe, David O. Matson

Community & Environmental Health Faculty Publications

Rotaviruses were discovered in the 1960s in animals and in the 1970s in humans; the latter discovery was made by an intrepid group who performed duodenal biopsies on children with acute gastroenteritis (AGE) [1]. By the late 1970s, data already clearly indicated that rotavirus was the cause of the annual winter peak of AGE affecting young children, as well as a frequent cause of severe gastroenteritis in various animal species (e.g., [2–5]). Use of the retrospectroscope clarified or left as tantalizing the suggestion that rotaviruses were the cause of the annual “winter vomiting syndrome” first described in children in 1910 …

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 …

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 …

Defensin In The Ticks Dermacentor Variabilis And Ixodes Scapularis, Shane Michael Ceraul

Theses and Dissertations in Biomedical Sciences

This dissertation presents the identification, molecular structure and expression of defensin, an antimicrobial peptide, in the ticks, Dermacentor variabilis and Ixodes scapularis. A 624 bp cDNA molecule for defensin was cloned and sequenced from hemocytes, fat body and midgut of unstimulated D. variabilis ticks. Defensin peptide was detected only in the hemocyte lysates. These results suggest that the defensin from D. variabilis is synthesized and stored in the hemocytes, although the role of other tissues is not excluded.

The ability of the juvenile stage ticks to express the defensin gene was confirmed. Detection of the defensin transcript in all …

The Defensin Gene In Dermacentor Variabilis And Ixodes Scapularis, Katherine Corbett Seguin

Biological Sciences Theses & Dissertations

In response to microbial challenge, invertebrates rely on their innate immune response to recognize and destroy harmful pathogens. One of the primary proteins produced by the response and that has been observed in many invertebrates, including insects, mussels, and ticks, is defensin. These proteins are responsible for forming pores in the membranes of invading microbes thereby destroying them. This study examined the gene coding region for defensin in two important tick disease vectors, Dermacentor variabilis and Ixodes scapularis. PCR amplification of the genes from tick chromosomal DNA resulted in the amplification of a 225 base pair amplicon. Sequencing of …

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.

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 …

Characterization Of Mouse Prostate Tumor-Infiltrating Leukocytes, Daniel Alan Holterman

Theses and Dissertations in Biomedical Sciences

Prostate cancer is the most common form of non-cutaneous cancer among men in the United States and the second most common cause of cancer-related death among men with approximately 189,000 new cases diagnosed and 30,200 deaths of the disease in 2002. Prostate cancer can be a treatable disease but once it becomes metastatic there are no acceptable therapies. For this reason, immunotherapy has been attempted but the results have been disappointing. The TRAMP model was used to evaluate specific interactions between an intact murine immune system and a prostate tumor that expressed a naturally processed weak tumor antigen. Vaccination trials …

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 …

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 …

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 …

Investigations Into The Innate Resistance Of The Tick, Dermacentor Variabilis, When Challenged With The Bacterium, Escherichia Coli, Shane Michael Ceraul

Biological Sciences Theses & Dissertations

In addition to the 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. This study was done to determine how ticks control infection by E. coli. Ticks were challenged by direct inoculation of bacteria into the hemocoel cavity. Using plate counts, no viable E. coli were detected I hour post-inoculation. A direct fluorescence assay (DF A) …

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, …

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 …

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 …

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.

Diffusion Problems In Wound Healing And A Scattering Approach To Immune System Interactions, Julia Suzanne Arnold

Mathematics & Statistics Theses & Dissertations

A theoretical model for the existence of a Critical Size Defect (CSD) in certain animals is the focus of the majority of this dissertation. Adam [1] recently developed a one-dimensional model of this phenomenon, and chapters I–V address the exist the CSD in a two-dimensional model and a three-dimensional model. The two dimensional (or 1-d circular) model is the more appropriate for a study of CSD's. In that model we assume a circular wound of uniform depth and develop a time-independent form of the diffusion equation relevant to the study of the CSD phenomenon. It transpires that the range of …

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 …

Cytotoxic T Cell Response To Influenza Vaccination In Older Adults, Caroline R. Letter

Chemistry & Biochemistry Theses & Dissertations

Influenza infections result in activation of cellular and humoral immune responses, leading to stimulation of cytotoxic T cells (CTL) and helper T cells with subsequent viral clearance.

By using an assay of granzyme B activity, the in vivo cellular-mediated immune response of old adults was found to be significantly decreased in comparison to young adults. The effect of aging on the CTL response was further investigated via enzyme-linked immunospot technique. A significant increase in number of virus-specific T cells occurred in older adults after vaccination, although the magnitude of the CTL response decreased in comparison to young adults. These data …

The Effect Of Illicit Drugs On The Cardiovascular And Hormonal Responses In Pregnant Rabbits, Andrea Alana Chambliss

Biological Sciences Theses & Dissertations

The purpose of this study is to determine the effect of acute administration of heroin and ecgonine methyl ester (EME) on renin and atrial natriuretic peptide (ANP) secretion in time dated New Zealand White rabbits. Thirteen rabbits were studied. Arterial blood pressure and pCOz, increased significantly from a control value of 80 ± 8 mmHg and 30 ± 2 mmHg respectively to 93 ± 18 mmHg and 31 ± 1 mmHg. pO₂ decreased from 99 ± 8 mmHg to 90 ± 11 mmHg 10 minutes after heroin administration. EME caused arterial blood pressure to significantly increase from a control …

Characterization Of P39, A Borrelia Burgdorferi Specific Protein, Jill M. Troyer

Theses and Dissertations in Biomedical Sciences

Borrelia burgdorferi, the causative agent of Lyme disease, expresses a species specific, 39 kiloDalton protein of unknown function called P39. This protein is highly immunogenic and the presence of anti-P39 antibodies in patient sera is used as an indicator of B. burgdorferi infection. P39 is also a candidate for vaccine developement due to conserved expression of P39 among B. burgdorferi isolates. Since little is presently known about this important molecule, the present study was designed to characterize P39 and was carried out in six separate investigations. First, infectious and noninfectious isolates of B. burgdorferi were established in vitro, and …

Neuronal Toxicity Of Humoral Factors From Patients With Diabetic Neuropathy And Mechanism Of Neuronal Death On Cultured Adrenergic Neurons: Studies Of Autoimmune Pathogenesis In Diabetic Neuropathy, Dong Liu

Theses and Dissertations in Biomedical Sciences

Diabetic neuropathy is an extremely common medical problem because of the high frequency of diabetes and its complications. Diabetic neuropathy consists of not one, but many patterns of nerve injury, each potentially with its own discrete pathogenic mechanisms. Evidence is accumulating that indicates autoimmunity plays a role in diabetic peripheral neuropathy. However, the significance of immunopathogenesis of diabetic neuropathy is as yet unclear.

Using the N1E-115 mouse neuroblastoma cell line (NB) as a model of the adrenergic autonomic neuron, we found that sera of IDDM patients with neuropathy inhibit growth and differentiation of adrenergic neurons in culture (Pittenger et al, …

Characterization Of An Antiviral Agent Based On Nonionic Surfactants And It's Effects On Human Dermal Fibroblasts, Ji Young Li

Biological Sciences Theses & Dissertations

The AIDS ·pandemic has directed various research endeavors towards finding an appropriate method for eliminating all potentially infectious material within bone allografts before implantation into a recipient. To that effect, Panavirocide was conceived by Medicine and Applied Science·s, Inc. This compound, in which three nonionic surfactants serve as the active agents, has been shown to inactivate HIV-1 particles within blood and blood products. Because Panavirocide has never been used with allografts, the purpose of the present research was to characterize the nonionic surfactants for the putative alteration of the formulation by determining the critical micelle concentration values and to determine …