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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Desenvolupament i anàlisi d'un bioprocés per a l'obtenció de vectors adenovirals per a teràpia gènica

Gálvez Sánchez, Jordi 06 July 2010 (has links)
En les últimes dues dècades, la teràpia gènica ha permès plantejar noves aproximacions en l'àmbit de la medicina personalitzada. Es troba orientada a guarir malalties actualment incurables i/o a millorar ostensiblement la qualitat de vida dels pacients, gràcies a la introducció de material genètic al nucli de la cèl·lula diana per permetre, augmentar o suprimir l'expressió d'un gen específic amb finalitat terapèutica. El vector és l'agent que juga el paper cabdal en aquest mecanisme. D'entre els possibles tipus (virals i no virals), destaca el vector adenoviral per la seva preeminència en els actuals assajos preclínics amb humans i per la necessitat de proveir demandes de mercat importants. El present treball aborda el desenvolupament complet d'un bioprocés per a l'obtenció de vectors adenovirals per a teràpia gènica: estudia els diferents aspectes que conformen el bioprocés, i analitza la implementació a escala industrial de la millor alternativa possible. Com a punt de partida, es realitzen estudis previs per conèixer la interacció dels vectors adenovirals amb les línies cel·lulars productores existents. S'aprofundeix en les tècniques de cultiu de dos candidats cel·lulars concrets: HEK293 (adherent) i HEK293S (no adherent). A partir de la infecció d'ambdós amb el vector adenoviral, es caracteritzen els principals paràmetres del cicle infectiu, els quals permeten concloure que la línia cel·lular HEK293S resulta més apropiada en base a una major productivitat. Aquestes dades proporcionen la base per desenvolupar l'etapa de producció del bioprocés. Aquesta s'estructura entorn als tres factors fonamentals que descriuen la bioreacció (el monitoratge, l'estratègia i el sistema de producció), els quals s'analitzen en profunditat. Es demostra la validesa del mètode de la velocitat de consum d'oxigen (OUR) per realitzar el monitoratge en línia de l'activitat cel·lular durant les fases de creixement i d'infecció. Posteriorment, es decideix avaluar dues estratègies de producció: l'estratègia en discontinu (estratègia de referència) i l'estratègia en continu amb perfusió (estratègia que proporciona les condicions el més semblants possibles a les que tindria la cèl·lula in vivo). Finalment, s'apliquen els anteriors factors en l'anàlisi del sistema de producció, en concret, amb la utilització de dues alternatives: l'anomenat sistema convencional (bioreactor de tanc agitat Biostat Bplus) i el sistema no convencional (bioreactor basat en tecnologia d'un sol ús Wave Bioreactor). A partir dels resultats obtinguts, es pot constatar que l'estratègia de producció en continu amb perfusió proporciona elevades concentracions cel·lulars, incrementant-se també tant la productivitat com la concentració vírica final. D'altra banda, també es posen de manifest els avantatges operacionals del sistema de cultiu no convencional, encara que sacrificant la possibilitat d'utilitzar la mesura de la velocitat de consum d'oxigen (OUR). Per tal de completar el treball, es desenvolupa l'etapa de purificació del bioprocés. En aquesta s'analitzen les propietats del producte i del brou de cultiu, i s'avaluen dues estratègies de purificació. Aquestes es diferencien fonamentalment per la seva possibilitat de facilitar el canvi d'escala, de manera que es designen com a estratègia de purificació no escalable (basada en la ultracentrifugació) i escalable (basada en la cromatografia). La primera és comunament emprada a escala de laboratori; donat que es recull específicament la banda de densitat que conté el vector adenoviral, s'implementa per obtenir material amb una elevada puresa que serveixi com a referència a l'hora de comparar els resultats obtinguts amb l'estratègia escalable. Per portar a terme aquesta última, es dissenyen les operacions que la integren, i es determinen els paràmetres de purificació, entre ells el rendiment global de recuperació del producte final. Posteriorment, es realitza la caracterització del producte per determinar el seu grau de puresa. Els resultats obtinguts deixen palès que l'estratègia escalable presenta un rendiment global superior al de la no escalable, tot i que el grau de puresa aconseguit és inferior. Les dades experimentals, tant de la producció com de la purificació, permeten disposar de quatre alternatives amb l'objectiu d'analitzar la potencial implantació del bioprocés a escala industrial. El disseny i la comparació de les mateixes es realitza d'acord amb el seu dimensionament seguint unes bases de disseny comunes, i la seva valoració final es projecta en termes econòmics. A partir dels resultats obtinguts, l'alternativa més aconsellable d'ésser portada a la pràctica és la basada en el bioprocés integrat pel sistema de producció no convencional operant en continu amb perfusió. Aquesta memòria s'estructura, doncs, de manera que inicialment es fa una introducció (capítol 2), on es revisen les característiques de la teràpia gènica, dels vectors adenovirals i de les línies cel·lulars productores, així com del bioprocés i de l'estricta normativa de producció GMP que el regeix. Seguidament (capítol 3), es plantegen els principals objectius del treball. A continuació (capítol 4), es concentren els estudis previs que caracteritzen tant la línia cel·lular productora com la infecció amb el vector adenoviral. Al capítol 5, es presenta el desenvolupament de l'etapa de producció del bioprocés. Anàlogament, en el capítol 6, es desenvolupa l'etapa de purificació del mateix. En el capítol 7, es realitza l'anàlisi de procés de les alternatives sorgides. En el capítol 8, s'exposen les principals conclusions extretes del treball. Finalment, es presenten els materials i mètodes emprats (capítol 9), i s'afegeix l'apèndix (capítol 10), on es complementen alguns aspectes concrets d'aquest treball. / For the last two decades, gene therapy has allowed to bring up new approaches in personal medicine. Its goal is to cure illnesses through the introduction of genetic material to the nucleus of a target cell in order to allow, increase or suppress the expression of a specific gene with therapeutic purpose. The vector is the agent that plays the principal role in this mechanism. Among the possible types (viral and non viral), the adenoviral vector is one of the most important due to its pre-eminence in the current preclinical human assays. The present work achieves the complete development of a bioprocess for the obtention of adenoviral vectors for gene therapy: it studies the different aspects that conform the bioprocess, and analyzes the industrial implementation of the best alternative. As a starting point, previous studies are carried out for knowing the interaction of the adenoviral vectors with the existing producing cellular lines. Techniques are studied for culturing two cellular candidates: HEK293 (adherent) and HEK293S (non adherent). From the infection of both with the adenoviral vector, main parameters of the infective cycle are characterized, which allow to conclude that the cellular line HEK293S is more appropriate due to its higher productivity. These data provide the basis to develop the production of the bioprocess. This stage is based on the study of three fundamental factors that describe bioreaction (monitoring, culture strategy and production system), which are deeply analyzed. The oxygen uptake rate (OUR) method is developed to monitor the cellular activity during the phases of growth and infection. Later on, two culture strategies are evaluated: batch (reference stretegy) and perfusion (strategy that provides most similar conditions to those in vivo). Finally, the former factors apply to the analysis of the production system, in particular, with the utilization of two alternatives: the so called conventional system (stirred tank bioreactor Biostat Bplus) and the non conventional system (single use technology based Wave Bioreactor). From the results, it can be concluded that the perfusion strategy provides high cellular densities, increasing the productivity as well as the final viral concentration. On the other hand, some operational advantages of the non conventional system are outlined, in spite of losing the OUR measure. In order to complete the work, the purification stage of the bioprocess is developed. The properties of the product and the culture broth are analyzed, and two strategies of purification are evaluated. These differ in the possibility of increasing scale, so they are designated as non scalable strategy (based on ultracentrifugation) and scalable strategy (based on filtration and chromatography). The first one is commonly used at laboratory scale; given that the final product contains specifically the adenoviral vector, it is implemented to obtain referencie material with high purity when comparing the obtained results with the scalable strategy. The last one is developed based on the design of several operations. The characterization of the final product is carried out to determined its purity. The obtained results conclude that the scalable strategy shows higher global yield than the non scalable one, even though the degree of purity achieved is lower. The production and purification data allow to have four alternatives in order to analyze the potential implantation of the industrial bioprocess. The design and the comparison of these are carried out according to the same bases of design, and the final discussion is based on economical terms. From the results, the most advisable alternative of being brought to practice is the one based on the bioprocess operating in perfusion using the non conventional system. This memory is structured so it initially contains an introduction (chapter 2), where the characteristics of gene therapy, adenoviral vectors and the producing cellular lines, as well as the bioprocess are outlined. Next (chapter 3), the main objectives of the work are described. Next (chapter 4), the previous studies that characterize the producing cellular line as well as the infection with the adenoviral vector are concentrated. In chapter 5, the development of the production stage is presented. Analogously, in chapter 6, the purification stage is developed. In chapter 7, the process analysis of the alternatives is carried out. In chapter 8, main conclusions extracted from the work are set forth. Finally, the materials and methods used (chapter 9) are shown, and the appendix (chapter 10) is added, where some aspects of this work are complemented.
52

Molecular characterization of 33K protein of bovine adenovirus type 3

Kulshreshtha, Vikas 04 March 2009 (has links)
Bovine adenovirus type 3 (BAdV-3) is a non-enveloped icosahedral particle which contains a double stranded DNA genome. The genome of BAdV-3 is organized into early, intermediate and late regions. The late region is organized into seven regions L1-L7 (Reddy et.al., 1998). The L6 region of late transcription unit of BAdV-3 encodes one of the non structural protein named 33K protein. The objective of the present study was to characterize the 33K protein and to identify the viral/cellular proteins involved in the interaction with 33K protein.<p> The RT-PCR analysis revealed the presence of spliced and unsliced mRNAs encoding 33K and 22K proteins respectively in BAdV-3 infected cells. The 33K and 22K proteins share a N-terminus region of 138 amino acids. To determine the specificity of these two proteins, rabbit polyclonal antiserum was raised against peptides representing unique C- terminal regions of the proteins. Anti-33Kp serum detected two major proteins of 42 kDa and 22 kDa and five minor proteins of 39kDa, 35kDa, 29kDa, 25kDa and 19kDa in BAdV-3 infected cells or 33K transfected cells. Similarly, anti-22Kp serum detected three proteins of 41kDa, 39kDa and 37kDa in BAdV-3 infected cells. However, a protein of 39kDa and 37kDa was detected in 22K (having splice sites removed) transfected cells. The 33K protein is predominantly localized to the nucleus of BAdV-3 infected cells and is involved in stimulating the transcription from major late promoter. Analysis of mutant 33K proteins demonstrated that amino acids 201-240 and amino acid 204-231 are required for nuclear localization and MLP transactivation.<p> The adenovirus 33K protein appears to be a multifunctional protein performing different role in viral infection. Earlier study has shown that the 33K protein plays a role in viral capsid assembly and efficient capsid DNA interaction in BAdV-3 (Kulshreshtha et.al., 2004). The involvement of 33K protein in different steps of adenovirus replication may require protein protein interaction. Using 33K protein as bait in yeast two hybrid system, open reading frames (ORFs) of BAdV-3 were screened for the potential interactions with 33K protein. The 33K protein showed specific interactions with two late viral proteins- 100K and protein V (pV). The yeast two hybrid findings were validated by in vitro binding using <i>in vitro</i> synthesized transcription-translation products. It was demonstrated that the interaction of 33K with 100K and pV takes place during BAdV-3 infection. The stretch of amino acids 81-120 and 161-200 in 33K protein were involved in the interaction with pV and 100K protein.<p> For screening the cellular interactions, the 33K protein was used as a bait to screen bovine retina cDNA library. The yeast two hybrid screening revealed that the 33K protein appears to interact with bovine presenilin-1-associated protein / mitochondrial carrier homolog 1 (BoPSAP / BoMtch1) and bovine microtubule associated protein (BoMAP). However, subsequent analysis by various <i>in vitro</i> and <i>in vivo</i> assays could only confirm the interaction between 33K protein and BoPSAP/BoMtch1. In addition, the 33K protein was also shown to be colocalized with BoPSAP in mitochondria. Based on these observations, it may be possible that 33K protein may play an anti-apoptotic by interacting with BoPSAP since the human homolog of PSAP has been known to induce apoptosis.
53

Inclusion body hepatitis as a primary disease in commercial broiler chickens

Ekanayake, Samantha - 13 January 2010 (has links)
Inclusion body hepatitis (IBH) has been occurring as an economically important, emerging disease of broiler chickens in several countries. Historically, IBH has been identified as a secondary disease, often associated with common immunosuppressive diseases. However, few studies have identified IBH as a primary disease with no apparent association with immunosuppressive diseases. The objectives of this study were to develop an animal model of IBH in commercial broilers, to demonstrate vertical transmission of fowl adenoviruses (FAdVs) in broiler breeders and to control IBH in broilers by vaccinating their parents with an inactivated FAdV vaccine. In order to develop an animal model of IBH in commercial broilers, fourteen-day old broilers were inoculated intramuscularly with 1x104 1x107 CCID50 of either FAdV x11a-like virus, two strains of FAdV-8a (FAdV-8a strain TR-59 and FAdV-8a strain T8-A) or FAdV-11strain 1047. Four days following FAdV inoculation, 5% - 15% mortality was observed and dead birds showed histologic lesions of hemorrhagic necrotizing hepatitis. This animal model reproduced the clinical disease, and pathological lesions of IBH that have been described in commercial broilers. In order to demonstrate vertical transmission of the FAdV, 35-week-old broiler breeders were inoculated with 1x106 CCID50 of either FAdV x11a-like virus, FAdV-8a strain TR-59, FAdV-8a strain T8-A or FAdV-11 strain 1047. Eggs from infected breeders were collected and hatched seven days post-inoculation. Clinical signs or mortality were not observed in parents; however broiler progeny derived from broiler breeders inoculated with FAdV-8a strain T8-A had 30% IBH mortality by seven days of age. The hexon gene loop 1 sequence of the virus isolated from affected broiler progeny showed 100% identity to FAdV-8a strain T8-A. In order to demonstrate protection of broilers against IBH by vaccination of their parents, four groups of broiler breeders were vaccinated with either FAdV-8a strain T8-A (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion, or FAdV x11a-like virus (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion at the age of 12 and 15 weeks. The control group was inoculated with 20% oil-in-water emulsion. Broiler progeny were challenged with FAdV-8a strain T8-A to study the immunoprotective effect of the vaccine. Although, survival of broilers following FAdV-8a strain T8-A challenge was not significantly different among vaccinated and non-vaccinated groups (P>0.05), immunoprotective effect was enhanced by the increase dose of FAdV antigens (P>0.05). Further studies are necessary to improve the vaccine efficacy to protect broilers against IBH.<p> In conclusion, the results of this study support the hypothesis that IBH in broilers in Canada is a vertically-transmitted primary disease with no known immunosuppressive involvement. The results also demonstrated that inactivated antigens of FAdV are able to partially protect broilers against IBH by vaccinating their parents. Further studies with different formulations, and priming the immune system of broiler breeders with live FAdV prior to vaccination with inactivated FAdV vaccines are necessary to improve the efficacy of inactivated IBH vaccine.
54

Gene Delivery of Angiogenesis Inhibitor Vasostatin for Cancer Therapy

Chen, Li-Feng 29 August 2005 (has links)
The growth and metastasis of solid tumors are dependent on angiogenesis. An endogenous angiogenesis inhibitor, vasostatin, is the proteolytic fragment derived from the N-terminal 180 residues of calreticulin. Previous studies indicated that vasostatin specifically inhibits endothelial cell proliferation, angiogenesis and tumor growth. However, continuous administration of vasostatin is difficult and expensive to facilitate, thereby underscoring the need to develop gene delivery approach. Adenovirus vectors possess advantages for gene delivery including high titer, high infection efficiency and broad host range. The aim of the present study was to generate and characterize recombinant adenovirus vectors encoding vasostatin (Ad-VS) or Igk-fused vasostatin (Ad-Igk-VS), thereby to evaluate the efficacy of anti-angiogenesis gene therapy for tumor suppression. Recombinant Ad-VS and Ad-Igk-VS were generated and verified by PCR and western blot analysis. In addition, adenovirus encoding angiostatin was also produced as positive control for angiogenesis assays. Adenovirus-mediated vasostatin gene delivery specifically inhibited the proliferation of bovine aortic endothelial cells (BAEC), but not non-endothelial cells such as Hela or NIH3T3 cells. Moreover, vasostatin gene delivery potently inhibited the proliferation, migration and tube formation, but not secretion of matrix metalloproteinases (MMPs), in endothelial cells. Flow cytometry analysis indicated that vasostatin gene delivery induced apoptosis in BAEC. Using western blot analysis, it was revealed that gene delivery of vasostatin increased the levels of Fas and FADD in BAEC. In conclusion, adenovirus-mediated vasostatin gene delivery inhibited various angiogenesis processes at least via induction of Fas/FasL pathway and may hold potential for cancer therapy.
55

POMC Overexpression Stimulates MITF/HIF-1£\ Survival Pathway in B16-F10 Melanoma Cells

Kuo, Yu-Fen 01 September 2008 (has links)
Melanoma is a cancer of the pigment producing cells, melanocytes, and is the most serious type of skin cancer. Cancer is a condition in which one type of cell grows without limit in a disorganized fashion, disrupting and replacing normal tissues and their functions. Normal melanocytes reside in the outer layer of the skin and produce a brown pigment called melanin, which is responsible for skin color. Melanoma occurs when melanocytes become cancerous, grow, and invade other tissues. Pro-opiomelanocortin (POMC) is a precursor polypeptide of 241 amino acids and the prohormone of various neuropeptide, including corticotropin (ACTH), £\-melanocyte-stimulating hormone (£\-MSH), and £]-endorphin (£]-EP). Recently, we demonstrated that systemic POMC overexpression potently suppresses the growth and metastasis of B16-F10 melanoma in vitro and in vivo. However, despite potent inhibition of tumor proliferation and angiogenesis, B16-F10 melanoma still managed to survive after POMC gene therapy. The underlying survival mechanism of B16-F10 melanoma remains unclear. Microphthalmia-associated transcription factor (MITF) is a basic helix-loop-helix transcription factor that plays a key role not only in melanin synthesis, but also in melanocyte development and survival. Besides, MITF binds to the hypoxia-inducible factor-1£\ (HIF-1£\) promoter to stimulate its transcriptional activity. In this study, we investigate the influence of POMC gene delivery on the pro-survival MITF/HIF-1£\ pathway in B16-F10 melanoma cells. Quantitative RT-PCR and western blot analysis revealed that POMC gene delivery increased the MITF mRNA and protein level in B16-F10 melanoma cells. Besides, POMC gene delivery significantly enhanced the HIF-1£\-driven luciferase activities in melanoma cells. By transfection and puromycin selection, we generated and characterized a MITF-knockdown B16-F10 melanoma cells (MITF KD) stably expressing short hairpin RNA against MITF. The growth, invasion, and colonies formation of MITF-KD were similar to those of vector control. However, implantation of MITF-KD cells led to melanoma with significantly reduced tumor size compared with those in mice implanted with vector control cells. Histological analysis revealed a significant reduction of CD31-positive blood vessels in implantation of MITF-KD cells-treated tumors, which was accompanied with a decrease in Ki-67-positive proliferating cells and an increase in TUNEL-positive apoptotic cells. Moreover, POMC-mediated upregulation of MITF and HIF-1 £\ was significantly attenuated in MITF KD-B16-F10 cells. Acetylsalicylic acid (aspirin; ASA) is widely used as an analgesic/antipyretic drug. ASA exhibits a wide range of biological effects, including preventative effects against heart attack, stroke, and the development of some types of cancer. In our study, we found ASA enhanced cell proliferation. However, in invasion test, ASA had no effect on cell migration. POMC gene delivery elevated the mRNA and protein level of hemeoxygenase-1 (HO-1), a downstream effector of HIF-1£\ pathway and an enzyme catalyzing the converting reaction of heme to carbon monoxide, ion and biliverdine. Inhibition of HO-1 activities augmented the inhibitory effect of POMC gene delivery on proliferation, migration and anchorage-independent growth of B16-F10 melanoma cells. These studies indicated that activation of MITF/HIF-1£\/HO-1 indeed contributes to melanoma survival after POMC gene delivery.
56

Human adenovirus serotype 5 vaccines : routes of delivery and formulations for successful immunization

Dekker, Joseph Dylan 09 November 2010 (has links)
Delivery of medicinal products to specific targets can be aided by utilizing different routes of administration. Particular routes may be advantageous when delivering products designed for therapeutic drug delivery, gene therapy, or vaccination. Vaccine candidates must remain stable, be delivered to their proper compartments, and promote sufficient immune responses to their delivered antigens, properties that can be modulated by formulation, adjuvants, and alternate routes of administration. Recently, the nasal passageway has been recognized as a promising route, as mucosally delivered vaccines have the advantage of inducing protection at both mucosal surfaces, a common site of infection, and systemically. Human adenovirus serotype 5 (Ad5) is a candidate vaccine vector capable of being delivered through several routes and inducing strong immune responses to its delivered transgene. The studies presented include vaccination strategies following different routes of administration with various formulation components to determine the ability of Ad5 to deliver its transgene and induce immune responses. The first study screens formulation candidates’ effects on an Ad5-based vaccine’s transduction in vitro, cellular and humoral immune responses in vivo, and efficacy upon challenge in mice. Screening formulation candidates in vitro can eliminate ineffective formulations, thereby limiting animal testing. An Ad5-based Ebola virus vaccine delivered in a combination of mannitol, sucrose, and the surfactant, pluronic F68, improves survival against lethal Ebola challenge in a mouse model compared to delivery in PBS alone. The second study tests the effect of an intravenously delivered Ad5-based vaccine complexed with anti-Ad5 neutralizing antibodies on cellular and humoral immune responses. Different antibody ratios complexed to the Ad5 vector are able to induce disparate cellular and humoral responses. Ratios initiating a strong humoral response towards the Ad5 vector correlate with a reduction of the humoral response against the transgene and few transgene targeted effector T cells. Accordingly, ratios leading to minor humoral responses to the Ad5 vector resulted in stronger humoral responses to the transgene and a strong effector memory T cell response. Taken together, these studies provide insight on how to achieve necessary immune responses in vaccine protocols by testing routes of administration, formulations, and surface modifications of the Ad5 vector. / text
57

Cellular receptors for viruses with ocular tropism

Nilsson, Emma C January 2011 (has links)
Several viruses from different virus families are known to cause ocular infections, e.g. members of the Adenoviridae, Picornaviridae and the Herpesviridae families. These infections are spread by contact and in the case of adenoviruses (Ads) and picornaviruses they are also highly contagious. The ocular infections caused by Ads and picornaviruses are called epidemic keratoconjunctivitis (EKC) and acute hemorrhagic conjunctivitis (AHC), respectively. Historically, EKC is caused mainly by three types of Ads from species D: Ad8, Ad19 and Ad37. The infection is characterized by keratitis and conjunctivitis but also involves pain, edema, lacrimation and blurred vision. AHC is caused mainly by two types of picornaviruses: coxsackievirus A24v (CVA24v) and enterovirus 70 (EV70), and is characterized by pain, redness, excessive tearing, swelling and subconjunctival hemorrhages. In addition, blurred vision, keratitis, malaise, myalgia, fever, headache and upper respiratory tract symptoms can also be experienced. Both infections are problematic in many parts of the world, affecting millions of people every year. Despite the great need, the only treatment available today is supportive treatment; no antiviral drugs are available to combat these common viral infections. Ad37 has previously been reported to use sialic acid (SA) as its cellular receptor. Since there is no antiviral treatment available against EKC we wanted to evaluate the inhibitory effect of SA-based antiviral compounds on Ad37 binding to and infection of ocular cells. We found that multivalent compounds consisting of SA linked to a globular carrier molecule, in this case human serum albumin, efficiently blocked Ad37 binding and infection at low concentrations. Further attempts were then made to improve the effect by chemically modifying SA monosaccharides. However, no enhanced inhibitory effect was accomplished and the conclusion was that the best inhibitors are based on unmodified SA. We next hypothesized that development of efficient SA-based binding inhibitors may require detailed knowledge about the structure of the SA-containing receptor. Using a battery of biological and biochemical experiments, including glycan array, binding and infection assays, X-ray crystallography and surface plasmon resonance (SPR); we identified a specific glycan involved in the binding and infection of Ad37. This glycan turned out to be a branched, di-SA-containing motif corresponding to the glycan motif of the ganglioside GD1a. However, the ganglioside itself did not function as a cellular receptor, as shown by a number of binding and infection assays. Instead, the receptor consisted of one or more glycoproteins that contain the GD1a glycan motif. This glycan docked with both its SAs into the trimeric Ad37 knob resulting in a very strong interaction as compared to most other protein-glycan interactions. Hopefully, this finding will aid development of more potent inhibitors of Ad37 binding and infection. The receptor for CVA24v, one of the main causative agents of AHC, has been unknown until now. We showed that this ocular virus, like Ad37, is also able to use SA as a receptor on corneal cells but not on conjunctival cells. This suggested that CVA24v may use two different receptors. As for Ad37, the receptor used by CVA24v on corneal cells also appears to be one or more sialic acid-containing glycoproteins. We believe that these findings may be a starting point for design and development of candidate drugs for topical treatment of AHC.
58

Ganglioside Increases Metastatic Potential and Susceptibility of Prostate Cancer to Gene Therapy in vitro

Miklavcic, John Unknown Date
No description available.
59

Rapid development of optimized recombinant adenoviral vaccines for biosafety level 4 viruses

Sahib, Mickey M. 10 September 2010 (has links)
This thesis describes the production of adenovirus-based vaccines containing codon-optimized genes from Nipah virus and Crimean-Congo Hemorrhagic Fever virus. Genes encoding envelope proteins from Crimean-Congo Hemorrhagic Fever Virus and Nipah Virus were codon-optimized for translation in human cells and constructed using a modified method of non-gapped gene synthesis, while the entire M segment encoding the glycoprotein precursor for Crimean-Congo Hemorrhagic Fever Virus was commercially synthesized. Genes were cloned into recombinant human adenovirus serotype 5 and the resulting viral particles were amplified, titred and analyzed for in vivo efficacy. Results show that a modified method of non-gapped gene synthesis is an effective and efficient method of producing antigen-encoded DNA and at a fraction of the cost and time required for commercial synthesis. Furthermore, adenovirus-based vaccines induce both cellular and humoral immune responses providing for a highly efficacious vaccine during potential disease outbreaks, where time to completion is of utmost importance. This study has shown that recombinant adenoviral vaccines for Crimean-Congo Hemorrhagic Fever virus and Nipah virus can be produced rapidly and efficiently from virtual DNA sequence to optimized recombinant vaccines in just eight months.
60

Two-way Approach to Spinal Muscular Atrophy Therapy Development

Goulet, Benoit 23 September 2013 (has links)
Spinal muscular atrophy (SMA) is the most commonly inherited neurodegenerative disease that leads to infant mortality worldwide. There are no known cures for SMA, but small increase in protein levels of SMN can be beneficial. We have developed adenoviral (Ad) vectors that express a human transgene of SMN and have tested their safety in vitro. We have demonstrated that these viruses can effectively express the transgene following cell entry and that the levels are relative to the virus dose. The viruses do not appear to impact the health and function of the cells, and are capable of increasing the number of Gems. We also attempted to change the tropism of the viruses through fiber protein modifications in order to target muscles and motor neurons. Our results suggest that a therapy based on an Ad-SMN fiber-modified vector may ultimately be successful in treating patients of SMA.

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