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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

Towards Whole Cell Immunoproteome And Subproteomes Of Bordetella Pertussis

Tefon, Burcu Emine 01 February 2012 (has links) (PDF)
Bordetella pertussis is a gram-negative, human pathogen and etiologic agent of whooping cough (pertussis), a highly contagious, acute respiratory illness. In this study, the analysis of whole immunproteome and subproteomes of this microorganism was performed. The soluble cytoplasmic proteomes of B. pertussis Tohama I strain and a local isolate Saadet were separated by 2DE. By Western blot analysis, we identified 25 immunogenic proteins of three categories. In the first group, there were well-known proteins of the pathogen The second group comprised proteins which were already shown antigenic in certain pathogenic bacteria, but not in B. pertussis before. The third group of proteins were those which have not been shown to be immunogenic in any pathogen till the present study such as putative chromosome partition protein, preprotein translocase SecA subunit, carbamoyl-phosphate synthase large chain, PRP synthase, putative substrate-CoA ligase, lysyl-tRNA synthetase, fumaryl acetoacetase, putative peptidyl-prolyl cis-trans isomerase, aspartate-semialdehyde dehydrogenase, putative DNA-binding protein and a putative outer membrane protein. In our surfaceome study, surface proteins of two strains were identified by 2DE followed by MALDI-TOF-MS/MS analysis and also geLC-MS/MS. With these techniques 45 proteins were identified by 2DE and 226 proteins by geLC-MS/MS. The immunogenicity of surface proteins on 2DE gels were analyzed by Western blotting and among 11 identified immunogenic proteins glutamine-binding periplasmic protein, leu/ile/val-binding protein, one putative exported protein, and iron-superoxide dismutase were found to be immunogenic for the first time in Bordetella. It was also found that 16 proteins were differentially expressed in B. pertussis Saadet and Tohama I. Five proteins were expressed only in Saadet (adhesin, chaperone protein DnaJ, fimbrial protein FimX, putative secreted protein Bsp22 and putative universal stress protein), and two (ABC transporter substrate-binding protein and a putative binding protein-dependent transport periplasmic protein) only in Tohama I. In the secretome study, we identified 40 proteins by 2DE and 357 proteins by geLC-MS/MS. It was found that 12 proteins were immunogenic by Western blot analysis and the immunogenicity of putative secreted protein (BP1047) was shown for the first time in this study. In our study, PT subunit 2 and putative outer protein D (BopD) were more abundant in Saadet while one protein, glutamate synthase subunit beta was expressed at a higher level in Tohama I. Four proteins were expressed only in Saadet (two capsular polysaccharide biosynthesis protein, protein FimX and putative outer membrane permeability protein). The present study comprehensively covered almost the entire proteome of a crucial pathogen, demonstrated many novel antigens and identified hundreds of membrane-bound proteins, cell surface-associated and extracellular proteins. Thus, it is anticipated to greatly aid in a better understanding of pathogen-host relations, rational design of novel drugs and developing new generation vaccines against B. pertussis.
52

Ro52 : Structure and interactions of constructs of RING and B-box

Österberg, Emmy January 2014 (has links)
The ubiquitination process is vital to maintain the protein homeostasis in the cell. With high specificity it regulates degradation of proteins by tagging them with a small protein called ubiquitin. Four proteins are involved to perform the process and in this thesis one of these proteins is studied. This protein is called Ro52 and belongs to the TRIM protein family. It posses E3 ligase activity because of a N-terminal RING-domain and therefore it is responsible for the last step in the ubiquitination process. The structure of Ro52 is not totally solved and the function of the protein’s four domains is not fully understood. In this thesis three constructs of two domains from Ro52 (RING and B-box) is investigated by circular dichroism (CD), nuclear magnetic resonance (NMR) spectroscopy and auto-ubiquitination assay by Western blot. The goal was to gain deeper insight in structural and functional properties of these domains. In the end only two constructs were investigated because of time limitations. It was shown by NMR that one construct has similar structure as the wild type but lower stability, possibly due to shorter N-terminal region. Comparison of the results from CD measurements showed that the constructs were well structured but did not reveal any significant differences in secondary structure between the constructs. Functional analysis by Western blot encountered unexpected problems and no results were obtained. The current thesis provides a basis for further investigation of variant constructs jointly expressing the RING-B-box domains, and shows that even small changes may alter structure and stability in ways that might affect functional properties.
53

Pharmacological and molecular characterisation of P2Y receptors in endothelial and epithelial cells

D'Souza, Vijay Kenneth January 2007 (has links)
In light of the significant modulation of receptor activity previously shown by a peptide (designated L247), designed to mimic the third extracellular loop of the human P2Y2 receptor, the aim of this study was to use this peptide as an immunogen to generate and fully characterise polyclonal rabbit antibodies to the P2Y2 receptor. Other aims of this study were to characterise epithelial and endothelial cells for a thorough expression profile of P2Y receptor mRNA transcripts in order to provide a rapid screen for the molecular determinants of these receptors in these cells. These studies also aimed to confirm previously published pharmacology, thus, to set the basis for western blot studies using P2Y receptor antibodies. Bovine aortic endothelial cells that co-express P2Y1 and P2Y2 receptors; EAhy926, a human endothelial fusion cell line, that express P2Y2 receptors; and ECV304 human bladder cancer cell line, known to express P2Y2-like and P2Y11-like receptors were used in this study. The dose dependent accumulation of inositol phosphates and cAMP response to potent P2Y11 agonists and RT-PCR studies confirmed the functional expression of both P2Y2 and P2Y11 receptors in ECV304 cells. Likewise, the dose dependent accumulation of inositol phosphates in response to potent P2Y2 and P2Y6 agonists and the presence of mRNA transcripts confirmed the expression of functional P2Y2/4- like and P2Y6- like receptors in EAhy926 cells. Polyclonal antiserum raised against L247 peptide was affinity purified and the purified fractions showed strong immunoreactivity with immobilised immunogenic antigen in ELISA. In western blot analysis L247 rabbit polyclonal anti-P2Y2 antibody detected strong bands in ECV304 and EAhy926 cells. On pre-absorption with the immunogenic peptide these responses were abolished suggesting that this antibody is antigen specific. Agonist induced P2Y2 receptor desentisation studies in ECV304 cells showed that prolonged agonist incubation caused the receptor sequestration. The loss of bands caused by P2Y2 receptor desensitisation and sequestration in membrane enriched fractions of agonist incubated ECV304 cells confirmed the specificity of L247 antibody. This antibody also showed no immunoreactivity in 1321N1 human brain astrocytoma cells devoid of any P2Y receptor subtypes cells. Deglycosylation studies revealed that the P2Y2 receptors are glycosylated in ECV304 cells. The polyclonal rabbit anti-P2Y2 receptor antibodies obtained from commercial sources produced completely different immunoreactive profiles with multiple bands even in 1321N1 cells. Furthermore, in comparison to L247 anti-P2Y2 antibody the commercial antibody showed no difference between normal and agonist incubated cells suggesting that this antibody may not be recognising the P2Y2 receptors in ECV304 cells. Likewise polyclonal rabbit antibodies to other P2Y receptors either showed no response or showed strong immunoreactive profile with multiple bands even in 1321N1 cells suggesting that these antibodies may not have been extensively characterized. Furthermore, immunofluorescence studies with commercial anti-P2Y2 antibodies showed that they may be only recognising non-denatured receptors. These studies suggest that the L247 anti-P2Y2 antibody raised against peptide designed to mimic specific region in the third extracellular loop of human P2Y2 receptor is highly specific and sensitive and provides an important tool to study endogenously expressed P2Y2 receptors in both non-denatured and denatured state. These studies indicate that this strategy of generating antibodies may be used to generate highly specific antibodies to other P2Y receptor subtypes.
54

Immunoblotting of T-type Ca^2+ Channel Protein in Mouse Brain and Embryonic Heart by Using Two Antibodies against Ca_<v>3.1 Channels

Niwa, Noriko, Yasui, Kenji, Hojo, Mayumi, Kodama, Itsuo 12 1900 (has links)
国立情報学研究所で電子化したコンテンツを使用している。
55

Characterization of the humoral immune response in dogs after vaccination against the causative agent of the Lyme Borreliosis, Borrelia burgdorferi, with different vaccines using two different vaccination schedules / Charakterisierung der humoralen Immunantwort im Hund nach Impfung mit verschiedenen Impfstoffen gegen den Erreger der Lyme-Borreliose, Borrelia burgdorferi, unter Berücksichtigung zweier verschiedener Impfstrategien

Töpfer, Katharina 10 October 2005 (has links) (PDF)
Lyme-Borreliose, die mittlerweile in der nördlichen Hemisphäre wichtigste durch Vektoren übertragene Erkrankung, wird durch Spirochäten aus der Borrelia burgdorferi sensu lato Gruppe hervorgerufen. Viele der in letzter Zeit veröffentlichten Studien haben darauf hingewiesen, dass durch Antibiotikagaben eine vollständige Erregerelimination nach Infektion nicht erreicht werden kann. Eine prophylaktische Versorgung rückt somit immer weiter in den Vordergrund des Interesses. Eine Impfung ist jedoch auch nicht unproblematisch: Untersuchungen beim Menschen haben gezeigt, dass nach zweimaliger Immunisierung im ersten Jahr lediglich 68% der Probanden geschützt waren und mit einer weiteren, sich anschließenden Immunisierung der Schutz gesteigert werden konnte. Deshalb sollte die hier an Hunden durchgeführte Studie aufzeigen, ob durch eine dreimalige Impfstoffapplikation im Verlauf der Grundimmunisierung mit kommerziell erhältlichen Impfstoffen die im Hund gebildeten Antikörperspiegel zu steigern. Ein höheres Antikörperniveau führt zu einem verzögerten Antikörperabfall und somit zu einem verlängerten Schutz. Weiterhin sollte zusätzlich das induzierte Antikörperprofil näher charakterisiert und somit auch eine Aussage über die Wirksamkeit gegenüber verschiedenen Borrelienspezies ermöglicht werden. Die im Verlauf dieser Studie durchgeführten Untersuchungen zeigen, dass zunächst eine höher als erwartete Infektionsrate für die Lyme-Borreliose in Sachsen innerhalb der Hundepopulation auftritt. Der prozentuale Anteil seropositiver Tiere beträgt 20,3%. Eine serologisch nachgewiesene Infektion steht allerdings nicht in direktem Zusammenhang mit einem Ausbruch der Erkrankung und darf demnach nicht mit der Erkrankungsrate innerhalb der Hundepopulation gleichgesetzt werden. Die bisher auf dem Markt erhältlichen und hier untersuchten Impfstoffe Merilym (B. burgdorferi s. s. Lysatimpfstoff, Merial, Deutschland), LymeVax (B. burgdorferi s. s. Lysatimpfstoff, Fort Doge, USA), Biocan (B. garinii, B. afzelii Lysatimpfstoff, Bioveta, Tschechien), ProLyme (rekombinanter Outer surface protein A (OspA) Impfstoff, Intervet, USA) und RecombitekLyme (rekombinanter OspA Impfstoff, Merial, USA) wurden in seronegativen Tieren bezüglich der induzierten Gesamtantikörper, der spezifisch gegen OspA gerichteten Antikörper und ihrer Kreuzreaktivität gegenüber heterologen Spezies untersucht, wobei der Einfluss von zwei verschiedenen Impfstrategien von besonderem Interesse war. Durch eine dreifache Antigengabe im Rahmen der Grundimmunisierung konnte nur bei zwei der untersuchten Impfstoffe (Merilym und Biocan) eine deutliche Erhöhung der Antikörperspiegel erreicht werden, die sich aber statistisch nicht signifikant von den anderen unterscheidet. Somit ist eine Umsetzung dieses Impfregimes in die Praxis nicht zu empfehlen. Es zeigt im Verlauf des Jahres bei allen Impfstoffen ein Titerabfall, sowohl bei den Gesamtantikörpern, als auch bei den OspA-Antikörpern. Mit Ausnahme von Biocan, hier sind kaum OspA-Antikörper nachweisbar, induzieren alle Impfstoffe nach der Impfung vor allem OspA-Antikörper, die jedoch sehr schnell wieder abfallen und nach einem halben Jahr nur mehr in geringem Maße nachweisbar sind. Diese OspA-Antikörper sind speziesspezifisch und nur in sehr geringem Umfang kreuzreaktiv. Diese Ergebnisse weisen auf eine Suszeptibilität der geimpften Tiere bezüglich einer Borrelieninfektion innerhalb mehrerer Monate nach Impfung hin. Es empfiehlt sich eine dritte Immunisierung nach sechs Monaten, um auch in der zweiten Jahreshälfte schützende Antikörperspiegel zu ermöglichen. Untersuchungen der Kreuzreaktivität in-vitro sprechen für eine mangelhafte Bindungsfähigkeit induzierter Impfantikörper gegenüber anderen Borrelienspezies, die in Zusammenhang mit einem geringen Schutz in-vivo gesehen werden könnten. Somit ist ein rein speziesspezifischer Impfschutz wahrscheinlich. Da vor allem in Europa eine große Borrelien-Artenvielfalt vorherrscht, deuten die hier vorgestellten Ergebnisse eine nur gegen eine Spezies gerichtete Immunität bei geimpften Hunden an. Die Notwendigkeit der Entwicklung eines neuen Impfstoffes, basierend auf einer Mischung speziesspezifischer OspA-Antigene gewonnen aus B. burgdorferi s. s., B. garinii und B. afzelii in Kombination mit weiteren Antigenen, da der Schutzmechanismus beruhend auf OspA bereits durch eine OspA-Variation seitens der Borrelien durchbrochen werden kann, wird durch die hier vorgelegten Resultate gestützt. Da ein solcher Impfstoff bisher nicht erhältlich ist und die Schutzwirkung der erhältlichen Impfung als partiell angesehen werden kann, rücken einfache, aber in der Regel zuverlässigere Methoden in den Vordergrund. Die tägliche Entfernung von Zecken ist eine wirksame Vorgehensweise, um das Infektionsrisiko zu minimieren. Auch der Einsatz akarizider Substanzen und Repellentien bietet sich an, um die Übertragung der Borreliose und weiterer, von Zecken übertragene Erreger zu unterbinden. / Lyme-Borreliose, currently the most important vector-borne disease in the northern hemisphere, is caused by spirochetes from the Borrelia burgdorferi sensu lato complex. Recently published studies have indicated that a complete eradication of the bacterium from the host’s tissue by antibiotic treatment is not possible. Therefore prophylactic measures become more important. However, vaccines are not unproblematic: studies in humans have shown that only 68% of the participants were protected after two immunizations applied during the first year, while the level of protection rose when an additional immunization was given. Therefore, the study presented here was designed to reveal whether three initial immunizations with commercial vaccines are able to raise the antibody levels in dogs. Higher antibody levels are the basis for a delayed disappearance of antibodies due to natural decay and therefore provide an extended protection from infection. Furthermore, the induced antibody profile was subject of a more precise characterization in order to draw possible conclusions about their efficacy against other Borrelia species. The results presented in this study show a higher than expected prevalence of Borrelia burgdorferi sensu lato seropositivity in dogs from Saxony. The percentage of seropositive dogs was 20.3%. Since seropositivity is not necessarily linked with the onset of the disease, this result does not describe the disease incident in the dog population. In the course of the study, commercially available vaccines, Merilym (B. burgdorferi s. s. lysate, Merial, Germany), LymeVax (B. burgdorferi s. s. lysate, Fort Dodge, USA), Biocan (B. afzelii, B. garinii lysate, Bioveta, Czech Republic), ProLyme (recombinant Outer surface protein A (OspA) with adjuvant, Intervet, USA) and RecombitekLyme (recombinant OspA without adjuvant, Merial, USA) were evaluated for induced antibody levels and the amount of OspA antibodies in seronegative dogs, in which two different vaccination schedules were of special interest. In addition the cross reaction of antibodies on heterologous antigens was analyzed. Three immunizations during the first year with two (Merilym and Biocan) of the five vaccines tested increase the vaccinal antibody levels, but this increase of antibody levels is not statistically significant. Therefore a recommendation for a third antigen application within the first six weeks after basic immunisation can not be given. All vaccine-induced antibody levels show a decrease within the first year concerning total antibody titers as well as OspA antibody titers. Except for Biocan the specificity of the initially induced antibodies by vaccination are directed mainly against OspA. These antibody titers decrease quickly resulting in minimum amounts of detectable antibodies within the period of six months. These OspA antibodies are species-specific and show only a minor cross reactivity. The results presented here suggest that vaccinated animals are susceptible for a borrelia infection within months after immunization. Therefore a third vaccination six months after the basic immunization is advisable in order to induce a long lasting protective antibody level during the period of one year. These data generated with in-vitro systems suggest that only a species-specific protection can be expected in-vivo. The species heterogeneity within Europe suggests that the vaccine available in Europe only protects from infection with the species used for vaccine preparation. These results underline the necessity to develop a new vaccine consistent of a mixture of OspA derived from at least B. burgdorferi s. s., B. garinii and B. afzelii in combination with other antigens, since protection from infection via OspA can be circumvented by minor OspA variations on the part of the borrelia. Since such a vaccine is not yet available, and therefore other methods that provide protection are necessary. Daily control of the dog and the removal of adherent ticks can help to prevent a possible infection since borrelia take at least 24 hours to migrate from the midgut of the tick to the salivary gland where they can infect the host. In addition, the use of repellent or acarizides might be helpful to avoid attachment or achieve the death of adherent ticks and therefore minimize the risk of infection with borrelia as well as other tick-borne diseases.
56

Infektionen mit Borrelia burgdorferi sensu lato und deren serologischer Nachweis mittels spezifischer C6-Peptide bei Hunden sowie im murinen Infektionsmodell

Krupka, Inke 12 April 2010 (has links) (PDF)
Die sichere Diagnose der Lyme-Borreliose und der Nachweis des verursachenden Spirochäten Borrelia burgdorferi bei Mensch und Tier sind problematisch. In Nordamerika ist B. burgdorferi sensu stricto (B. burgdorferi s.s.) die einzige pathogene Spezies, während in Europa und Asien mit B. garinii und B. afzelii mindestens zwei weitere pathogene Arten vorkommen. B. valaisiana, B. spielmanii und B. lusitaniae werden ebenfalls als Verursacher der Lyme-Borreliose diskutiert. Der indirekte Erregernachweis durch Detektion von Antikörpern mittels Antigen aus Borrelienlysat im Zweistufentest (ELISA und Western-Blot) gilt seit langem trotz der anspruchsvollen Interpretationskriterien als Methode der Wahl. Ein hochspezifischer ELISA mit dem synthetischen C6 Peptid als Antigenkomponente ergänzt erst seit wenigen Jahren die Diagnostik. Das C6-Peptid basiert auf der invariablen Region 6, welche eine konstante Region des ansonsten hochvariablen Borrelien-Oberflächenproteins VlsE darstellt. Nur metabolisch aktive Borrelien exprimieren VlsE/C6 Epitope im Säugetierwirt. Studien zeigten, dass C6-Antikörper mehrere Monate nach einer potenziell erfolgreichen antibiotischen Therapie deutlich messbar und langfristig absinken. In Deutschland sind ein C6-Schnelltest (4Dx®SNAP®, IDEXX Inc., USA) und ELISA (Quant C6®, IDEXX Inc., USA) für die Serodiagnostik bei Hunden erhältlich. Über die Anwendbarkeit des C6-Peptids für die kanine Borreliosediagnostik in Deutschland liegen wenige Daten vor, aber zunehmend wird der Ersatz des Zweistufentests durch das C6-Peptid diskutiert. In dieser Arbeit sollte zunächst festgestellt werden, ob potenzielle kanine Infektionen in der Routinediagnostik mit dem C6-Peptid ebenso sensitiv detektiert werden können wie mit dem Zweistufentest und ob C6-positive Hunde nach einer Antibiose mit dem deutlichen Sinken der C6 Antikörperspiegel als Zeichen eines potenziellen Therapieerfolges reagieren. Dafür wurden 510 Sera von Hunden aus verschiedenen deutschen Tierarztpraxen untersucht, wobei neben der serologischen Untersuchung eine Analyse der Vorberichte erfolgte. Eine dort angegebene, bestehende Infektion konnte in 93,3 % der Fälle serologisch nicht bestätigt werden und nur bei 3,3 % der Hunde wurden infektionsspezifische Antikörper ermittelt. Der Zweistufentest und der C6 Schnelltest wiesen hier eine vollständige Übereinstimmung auf. Unabhängig vom Vorliegen klinischer Anzeichen wurden für diese Studie C6-positive Hunde mit Antibiotika behandelt. Vier bis 18 Monaten nach der Therapie wurde von insgesamt 27 Hunden eine zweite Blutprobe untersucht. Die C6 Antikörperspiegel waren bei acht Hunden im ELISA um mindestens 50 % gesunken. Für deutliche Effekte musste aber ein ausreichend hoher initialer C6-Antikörperspiegel vorliegen. Da in Europa mindestens drei pathogene Borrelienarten vorkommen, wurde in einem murinen Infektionsmodell analysiert, ob speziesspezifische C6-Peptide von B. burgdorferi s.s., B. garinii und zwei Varianten von B. afzelii sicher Antikörper detektieren, die durch definierte experimentelle Monoinfektionen mit B. burgdorferi s.s. N40, B. garinii PBi, B. afzelii Slovakia, B. afzelii PKo, B. valaisiana, B. spielmanii oder B. lusitaniae induziert wurden. Um die erfolgreiche Infektion zu belegen, wurden murine Gewebe zur Borrelienisolation in Kulturmedien inkubiert und zusätzlich eine qPCR zum Nachweis von ospA durchgeführt. Eine PCR zur Detektion von essenziellen Plasmiden ergab, dass die B.-lusitaniae- und B.-valaisiana-Isolate nicht infektiös waren. Eine Infektion konnte durch Gewebekultur und qPCR dagegen bei mit B.-burgdorferi-s.s.-, B- garinii-, B.-afzelii- und B. spielmanii-inokulierten Mäusen belegt werden. Die Ergebnisse des C6-Peptid-ELISAs wurden mit dem des Zweistufentests als Goldstandard verglichen und die Sensitivitäten der C6-Peptide ermittelt. Diese betrug bei C6-Peptiden von B. burgdorferi s.s. und B. garinii je 100 % für B.¬burgdorferi¬s.s.¬N40, B. garinii-PBi- oder B.-afzelii-PKo-spezifische C6-Antikörper. Dagegen konnten C6-Peptide basierend auf B. afzelii nur B.-afzelii-PKo-spezifische Antikörper zu 100 % erfassen. Antikörper gegen B. afzelii Slovakia wurden von jedem C6-Peptid schlechter erfasst als Antikörper gegen B. afzelii PKo, was das Vorkommen stamm- oder isolatspezifischer C6-Antikörperfraktionen nahelegt. Die Untersuchung der 27 C6-positiven Hundesera aus der serologischen Studie ergab zudem, dass der Großteil der Sera ausschließlich gegenüber B.-burgdorferi-C6 und B.-garinii-C6 deutlich messbar reagierte. Die Eignung des C6-Peptids in praxi als ein schneller, hochspezifischer Infektionsmarker für den serologischen Nachweis bei Hunden aus Deutschland kann bestätigt werden. Allerdings kann der alleinige Nachweis von C6-Antikörpern weder einen detaillierten Vorbericht, noch den Zweistufentest auf Lysatantigen-Basis ersetzen. Seine Eignung als Marker für einen potenziellen Therapieerfolg ist nur unter definierten Bedingungen gegeben. Die divergenten Sensitivitäten verschiedener C6 Peptidsequenzen gegenüber Antikörpern von in Europa vorkommenden Borrelien-Arten und Isolaten machen deutlich, dass zukünftig weiterer, intensiver Forschungsbedarf bezüglich der Etablierung von ausreichend sensitiven C6-Testsystemen für europäische Bedürfnisse notwendig ist.
57

Generation and characterization of antibodies for proteomics research

Larsson, Karin January 2009 (has links)
Specific antibodies are invaluable tools for proteomics research. The availability of thoroughly validated antibodies will help to improve our understanding of protein expression, localization and function; fundamental processes and features of all living organisms. The objectives of the studies in this thesis were to develop high-throughput methods to facilitate the generation and purification of monospecific antibodies, and to address problems associated with antigen selection for difficult target proteins and subsequent validation issues. In the first of the studies, it was demonstrated that antibodies specific to human proteins could be generated in a high-throughput manner using protein epitope signature tags (PrESTs) as both antigens and affinity ligands. A previously developed purification process was adapted to a high-throughput format and this, in combination with the development of a protein microarray assay, resulted in monospecific antibodies that were used for profiling protein expression in 48 human tissues. Data obtained in these analyses suggest that a complete Human Protein Atlas should be attainable within the next ten years. In order to reduce the number of animals needed for such a massive project, and improve the cost-efficiency of antibody generation, a multiplex immunization strategy was developed in a further study. Antisera from rabbits immunized with mixtures of two, three, five and up to ten different PrESTs were successfully purified and analyzed for specificity using protein arrays. Almost 80% of the animals immunized with up to three PrESTs yielded antibodies towards all the PrESTs administered, and they yielded comparable immunohistochemical staining patterns (of consecutive human tissue sections) to those of antibodies obtained from traditional single PrEST immunizations. Proteins with highly similar sequences to other proteins present a major challenge for the proteome-wide generation of antibodies. In another study, Cytokeratin-17 which displays high sequence similarity to closely related members of the intermediate filament family, was used as a model and the specificity and cross-reactivity of antibodies generated against this target were investigated using epitope mapping in combination with comparative IHC analyses. Antibodies identified by epitope mapping as binding to the most unique parts of the Cytokeratin-17 PrESTs also showed the most Cytokeratin-17-like staining pattern, thus further supporting the strategy of using sequence identity scores as the main criteria for PrEST design. An alternative antigen design strategy was investigated for use in raising antibodies towards G-proteincoupled receptors (GPCRs). The extracellular loops and N-terminus of each of three selected GPCRs were assembled to form single antigens and the resulting antibodies were analyzed by flow cytometric and confocal microscopic analyses of cell lines over-expressing the respective receptors. The results from both flow cytometric and immunofluorescence analyses showed that the antibodies were able to bind to their targets. In addition, the antibodies were used successfully for the in situ analysis of human brain and pancreatic islet cells. / QC 20100727
58

Obtenção e caracterização de antígenos de toxocara vitulorum por SDS-page e western blot

Ferreira, Fabiano Pan [UNESP] 26 July 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-07-26Bitstream added on 2014-06-13T18:39:27Z : No. of bitstreams: 1 ferreira_fp_me_ilha.pdf: 272949 bytes, checksum: 557ad0d6f0ab0423f56e4256406ff28d (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Toxocara vitulorum é um parasita nematódeo de alta freqüência no trato intestinal de búfalos, particularmente em bezerros búfalos de um a três meses de idade. Devido à sua alta morbidade e mortalidade, causa consideráveis prejuízos a bubalinocultura. A pesquisa objetivou a obtenção de antígenos de extrato larval solúvel bruto (Ex), do material excretor-secretor (ES) de larvas infectantes e do líquido perientérico (Pe) de adultos de T. vitulorum, bem como a separação das frações protéicas na mistura pelo SDS-PAGE, seguida da análise imunológica por Western blot (WB), utilizando-se soros imunes e colostros de búfalos naturalmente infectados com T. vitulorum além de camundongos imunes. O acompanhamento do quadro parasitário dos bezerros búfalos também foi realizado. Pôde-se verificar que os três antígenos, Pe, Ex e ES, apresentaram mobilidades eletroforéticas pelo SDS-PAGE revelando nove (11,5, 14,2, 31, 38, 58, 76, 88, 112 e 165 KDa), onze (11,2, 13,3, 16,5, 22, 25, 32, 43, 53, 68, 82 e 96 KDa) e oito (19, 48, 56, 64, 90, 110, 150 e 190 KDa) bandas protéicas, respectivamente. A maioria dessas frações separadas pela eletroforese, foi reconhecida por todos as amostras de soros e pelo colostro, quando analisada pelo WB. No entanto, somente as bandas de alto peso molecular (68 - 190 KDa) persistiram nos grupos de bezerros búfalos que se encontravam no pico, declínio ou expulsão e na ausência ou autocura, à exceção do antígeno ES, que desapareceu durante o processo de autocura. Já os soros de bezerros búfalos com um de vida, que mamaram o colostro e os daqueles que se encontravam em fase de aparecimento ou ascensão, revelaram com as mesmas frações detectadas no soro e no colostro das búfalas. Os três antígenos reagiram de forma cruzada entre si, quando foram testados com soros homólogos e heterólogos de camundongos imunizados experimentalmente com estes antígenos de T. vitulorum / Toxocara vitulorum is a nematode parasite of small intestine of cattle and water buffaloes particularly buffalo calves with one to three months of age, causing high morbidity and mortality. The purpose of this research was the antigen obtaintion and characterization of crude soluble larval extract (Ex), excretory-secretory (ES) of infective larvae, and perienteric fluid (Pe) from adults of T. vitulorum, as well as the separation of protein fractions from the antigenic mixture by SDS-PAGE and analysis of each band by Western blot (WB), using immune sera and colostrum of buffaloes naturally infected by T. vitulorum, and mice experimentally immunized. The parasitological status of the buffalo calves was also evaluated using sequentially coprological examinations. The results showed that three antigens, Pe, Ex and ES, revealed nine (11,5, 14,2, 31, 38, 58, 76, 88, 112, and 165 KDa), eleven (11,2, 13,3, 16,5, 22, 25, 32, 43, 53, 68, 82, and 96 KDa) and eight (19, 48, 56, 64, 90, 110, 150, and 190 KDa) protein bands by SDS-PAGE, respectively. The majority of these isolated bands were recognized by sera and colostrum of all groups of infected animals (buffalo cows one day post parturition and buffalo calves in five different periods of T. vitulorum infection) analyzed by WB. However, only the fractions of high molecular weight (68 - 190 KDa) persisted in the groups of buffalo calves at maximum peak of infection, expulsion and post-expulsion of the parasite or self-cure process, excepting ES antigen, that was not detected during the self-cure process. Sera of buffalo calves at one day of age, after suckling the colostrum and at the beginning of infection reacted with the same bands detected by serum and colostrum of the buffalo cows. The three antigens showed crossed reaction among themselves, when they were tested with homologous and heterologous sera of mice experimentally immunized with them
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Analýza rekombinantních klonů apoptotické nukleázy v systému "leaf factory" při koinfiltraci modifikujícími geny / Analysis of recombinant clones of apoptotic nucleases in "leaf factory" system upon coinfiltration with modifying genes

LOMNICKÁ, Anna January 2011 (has links)
TBN1 is a nuclease with antitumor activity. The main goal of this work was to estimate how TBN1 and its modificated variants are stable in the ?leaf factory? system used for its production and whether it can be enhanced or influenced by chosen potential ?modificators? i. e. silencing supressors, transcription factors, glycosyltransferases and kinases. Nicotiana benthamina plants were infiltrated with the mixture of Agrobacterium tumefaciens strains bearing the nuclease plant expression vectors and co-infiltrated with the ?modifying? vectors. The nuclease and protein analyses revealed that nuclease TBN1 wt and its modificated variants are stable in the used ?leaf factory? system as to their molecular mass, only quantitative changes were detected. Expreximents showed that activity and production of the nucleases increased upon coinfiltration with silencing supressor and decreased upon coexpression with chosen transcription factor. Glycosyltransferases and kinases influenced activity and production only insignificantly. The experiments also revealed that modificated variants of TBN1 have different molecular weight suggesting that different N-glycosylation domains have different length of sugar chain and influence on nuclear activity. Our data show that this expression in planta seems to be suitable for production for study of antitumor activity of these nucleases.
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Caracterização de Mycoplasma agalactiae isolados no Brasil e produção de vacinas contra agalaxia contagiosa

CAMPOS, Ana Claudia 29 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-07-28T12:55:08Z No. of bitstreams: 1 Ana Claudia Campos.pdf: 1040308 bytes, checksum: b0653bfe634b8d58d0d6d1c3c04816e9 (MD5) / Made available in DSpace on 2016-07-28T12:55:08Z (GMT). No. of bitstreams: 1 Ana Claudia Campos.pdf: 1040308 bytes, checksum: b0653bfe634b8d58d0d6d1c3c04816e9 (MD5) Previous issue date: 2012-02-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Mycoplasma agalactiae is the main causative organism of contagious agalactia (CA), a disease characterized by mastitis followed by agalactia, polyarthritis, and keratoconjunctivitis. In 2001, M. agalactiae was isolated and identified in Brazil, causing great economic losses. Considering the need for characterization of Brazilian strains of M. agalactiae and implementation of effective control, this work was performed in three steps. The first article describes the biochemical and protein profile of isolates of M. agalactiae in small ruminants through the culture in modified Hayflick medium, biochemical tests, polyacrylamide gel electrophoresis (SDS-PAGE) and immunogenicity of these proteins by Western blot (WB). The samples had similar protein in the profile bands ranging from 30-135 kDa in SDS-PAGE, in addition the presence of a protein of 48 kDa immunodominant WB was shown. To continue identifying the agent involved in the AC in Brazil, the second article describes the analysis of ten sequences of M. agalactiae isolated from goats and sheeps. A DNA fragment of 360 bp of the 16S rRNA gene was amplified by PCR and sequenced. The analysis revealed a high degree of similarity among all the sequences. The study revealed greater than 99% similarity with the reference samples of M. agalactiae. In the third article, efficacy of three inactivated vaccines prepared with a local of M. agalactiae sample and adsorbed with three adjuvants was evaluated in goats and sheep. The antibody response in vaccinated animals was analyzed using an indirect ELISA. The three vaccines induced antibody production, and can be an alternative to reduce economic losses and prevent contagious agalactia. These results confirms the presence and spread of M. agalactiae in the country and enhances the possibility of controlling the disease through the adoption of livestock vaccination. / Mycoplasma agalactiae é o principal microrganismo causador da agalaxia contagiosa (AC), doença caracterizada por mastite seguida de agalaxia, poliartrite e ceratoconjuntivite. Em 2001, M. agalactiae foi isolado e identificado no Brasil, determinando grandes prejuízos econômicos. Considerando a necessidade de caracterização de amostras brasileiras de M. agalactiae e da implantação de medidas eficazes de controle, esse trabalho foi realizado em três etapas. O primeiro artigo descreve o perfil bioquímico e protéico de isolados de M. agalactiae de pequenos ruminantes através do cultivo em meio Hayflick modificado, testes bioquímicos e eletroforese em gel de poliacrilamida (SDS-PAGE) e a imunogenicidade destas proteínas por Western Blot (WB). As amostras apresentaram similaridade no perfil protéico com bandas variando de 30 a 135 kDa no SDS-PAGE, além da presença de uma proteína imunodominante de 48 kDa no WB. Para dar continuidade a identificação do agente envolvido na AC no Brasil, o segundo artigo descreve a análise de dez sequências de M. agalactiae isolados de caprinos e ovinos. Um fragmento de DNA de 360 bp do gene 16S rRNA amplificado por PCR foi sequenciado. A análise revelou alto grau de similaridade, entre as dez sequências e uma similaridade maior que 99% com amostras de referência de M. agalactiae. No terceiro artigo, a eficiência de três vacinas inativadas, preparadas com amostra local de M. agalactiae e adsorvidas com três adjuvantes, foi avaliada em caprinos e ovinos. A resposta sorológica dos animais vacinados foi analisada através de um ELISA indireto. As três vacinas induziram produção de anticorpos, podendo ser utilizadas como uma alternativa para reduzir as perdas econômicas e prevenir a agalaxia contagiosa. Estes resultados confirmam a presença e disseminação do M. agalactiae no país e fortalece a possibilidade de controle da doença pela adoção da vacinação dos rebanhos.

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