No description available.

No description available.

Immunoassays for 2-methylisoborneol (MIB) and monensin in water were developed, devised and tested to see if the sensitivity could be established and improved. MIB and monensin are hydrophobic haptens with molecular weights of 168 and 671 Da, respectively. Rabbits were immunized with (-) camphor-BSA and (-) borneol-BSA for the production of polyclonal antibodies (pAbs) to MIB. Monoclonal antibodies (mAbs) were produced in Mus musculus using (-) camphor-BSA as immunogen. (+) Bornylamine-thyroglobulin (TG) and MIB-TG were synthesized and used as plate coatings. For the monensin immunoassay, monensin was conjugated to BSA and OVA for immunogen and plate coating, respectively. Several physical parameters that affect the sensitivity of immunoassays including pre-incubation of antibody and antigen, incubation time and temperature, detergent, organic solvents, and ionic strength were evaluated. Improvement of immunoassay sensitivity was also performed by reducing the concentrations of coating antigen and antibodies and using alternative reporter systems such as chemiluminescence (CICL-ELISA), tyramide signal amplification (TSA) and biotin-streptavidin. Different assay formats, i.e., competitive indirect and competitive direct were also compared. Usability of both pAb-based immunoassays for MIB and monensin was evaluated in fortified water samples. A polyclonal-based (pAb) ELISA for MIB had a detection limit of 4.8 ng mL-1 and an IC50 of 105 ng mL-1. Rabbits immunized with (-) camphor-BSA showed a higher immune response than rabbits immunized with (-) borneol-BSA. One clone (i.e., 4F11) of fourteen characterized clones was used to create the monoclonal antibody (mAb)-based ELISA, which had an IC50 of 100.2 ng mL-1 and an LOD of 1.9 ng mL-1. The pAb- and mAb-based CI-ELISA were not specific to MIB alone and cross reacted with camphor and camphor-like compounds. Meanwhile, a pAb-based ELISA for monensin produced a detection limit of 0.1 ng mL-1 and had an IC50 of 1.056-1.090 ng mL-1 with high specificity to monensin. Other reporter systems did not improve the sensitivity of the immunoassays significantly. MIB and monensin polyclonal-based assays showed good correlation to analytical instrumental methods (i.e., GC-MS and LC-MS) in fortified water samples. With a detection limit of ca. 5 ng mL-1 and 0.1 ng mL-1 for MIB and monensin, respectively, both polyclonal-based assays can be used for detection of these analytes in water from different sources and employed as screening tools to complement GC/HPLC-MS instrument methods.

Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-03-08T19:19:08Z No. of bitstreams: 1 117110029.pdf: 698994 bytes, checksum: ceaed51c4f43c77fa5dcfffa7ec011b5 (MD5) / Made available in DSpace on 2015-03-08T19:19:08Z (GMT). No. of bitstreams: 1 117110029.pdf: 698994 bytes, checksum: ceaed51c4f43c77fa5dcfffa7ec011b5 (MD5) Previous issue date: 2013-08-09 / Os vírus são importantes agentes patogênicos de várias espécies animais, entre elas bovinos. No Brasil, diversos agentes virais foram descritos causando infecções no rebanho bovino, e produzindo perdas econômicas significativas. A identificação dos animais infectados por um vírus pode ser realizada de diferentes formas; no entanto, a confirmação definitiva requer a demonstração do agente ou da resposta imune. Para isto, vários métodos com capacidade de detectar a partícula viral, atividade biológica, genoma, antígenos virais, ou então a resposta imune específica foram desenvolvidos. Os imunoensaios são testes amplamente utilizados na rotina laboratorial para detecção de antígenos virais em amostras clínicas ou de pesquisa. Estes ensaios apresentam boa sensibilidade, especificidade e facilidade de execução. A metodologia dos imunoensaios tem como base, o emprego de anticorpos monoclonais ou policlonais específicos para os antígenos virais. Assim sendo, o objetivo do presente estudo foi produzir anticorpos policlonais para alguns vírus bovinos, e avaliar a reatividade destes em testes de imunofluorescência, imunoperoxidase e slot blot. Para isto, cepas e/ou isolados do herpesvírus bovino tipo 1 (BoHV-1), herpesvírus bovino tipo 2 (BoHV-2), herpesvírus bovino tipo 5 (BoHV-5), herpesvírus bovino tipo 5 gE deletado (BoHV-5 gEΔ), vírus da diarreia viral bovina (BVDV), vírus respiratório sincicial bovino (BRSV), vírus da língua azul (BTV) e vírus da vaccínia (VACV) foram amplificados em cultivo celular e o sobrenadante utilizado para imunizar coelhos. Os animais foram imunizados cinco vezes pela via subcutânea, e cinco dias após o último reforço coletou-se sangue. O soro foi separado do sangue por centrifugação. O soro foi diluído em PBS (1:100 a 1:204.800) e utilizado como anticorpo primário nos ensaios de imunofluorescência, imunoperoxidase e slot blot. A diluição de trabalho foi selecionada pela diluição que produziu reação específica nas células infectadas, e sinal fraco ou ausente nas células controle. Os antissoros apresentaram maior reatividade na técnica de imunoperoxidase do que na imunofluorescência e slot blot. Ainda, para os antissoros do BoHV-1, BoHV-5, BVDV e BRSV demonstrou-se a reatividade com amostras heterólogas nos ensaios de imunofluorescência e imunoperoxidase. Conclui-se que os anticorpos policlonais produzidos em coelhos possuem elevadas concentrações de anticorpos específicos, o que foi detectado pela reatividade nos ensaios de imunofluorescência, imunoperoxidase e slot blot. Desta maneira, estes reagentes podem ser considerados uma importante ferramenta para a detecção e caracterização de vários vírus bovinos na rotina de diagnóstico e pesquisa. / The viruses are significant important pathogenic agents of several animal species, including cattle. In Brazil, several viral agents causing infections have been described in cattle and they produce significant economic losses. The identification of animals infected by a virus can be performed in different ways; however, definitive confirmation requires demonstration of the agent or immune response. For this purpose, various methods with the capacity to detect the viral particle, biological activity, genome, viral antigens, or specific immune response have been developed. Immunoassays are widely used in laboratory routine for detection of viral antigens in clinical or research. These assays exhibit good sensitivity, specificity and easy for implantation. The immunoassay methodologies are based on the employment of monoclonal or polyclonal antibodies specific to the viral antigens. Therefore, the aim of this study was to produce polyclonal antibodies for some bovine virus, and evaluate their reactivity in immunofluorescence, immunoperoxidase and slot blot tests. For this purpose, strains and/or isolates of bovine herpesvirus type 1 (BoHV-1), bovine herpesvirus type 2 (BoHV-2), bovine herpesvirus type 5 (BoHV-5), bovine herpesvirus type 5 gE deleted (BoHV-5 gEΔ), bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), bluetongue virus (BTV), and vaccinia virus (VACV) were amplified in cell culture and the supernatant were used to immunize rabbits. The animals were immunized five times by the subcutaneous route, and five days after the last boost the blood was collected. The serum was obtained by centrifugation. The serum was diluted (1:100 a 1:204.800) and used as primary antibodies in the immunofluorescence, immunoperoxidase and slot blot assays. The working dilution was selected among those produced specific reaction with infected cells and absent or weak background in control cells. The antiserum showed higher reactivity in immunoperoxidase technique than the immunofluorescence and slot blot. The antiserum of the BoHV-1, BoHV-5, BVDV and BRSV presented the reactivity when tested with eterologous isolates in immunofluorescence, immunoperoxidase assays. In summary, that the polyclonal antibodies raised in rabbits have high concentrations of specific antibodies, which were demonstrated by the reactivity in immunofluorescence, immunoperoxidase and slot blot assays. Additionally, these reagents can be considered an important tool for the detection and characterization of various bovine viruses in diagnostic and research routine.

The present research focused on the development of a new methodology to assess the strength of the interaction between vaccine antigens and elicited polyclonal antibodies through SPR biosensors. Quantifying the binding strength of polyclonal antibodies is of first importance to evaluate the quality of the vaccine as well as to increase the scientific knowledge of immune protection mechanisms. To now the development of such tool has been complicated by the non-specific binding caused by high protein abundance in the blood and serum samples but also by the way of interpreting the data resulting from multi-interaction events measured at the same time. At first, we unsuccessfully tried to segregate the individual affinity contribution of each antibody population by measuring the signal as the sum of singular interactions. Differentiation of the singular contribution would have needed the fulfillment of the “additivity” hypothesis, meaning that each antibody bind identically alone or in mixture with other antibody. This hypothesis was not met and mathematical assessment by the sum of singular contribution led to fitting results that did not reflect the biological reality. It was therefore decided to switch the analysis method and to measure the end association binding level reached by the different samples injected at the same specific antibody content. The dissociation behavior was interpreted by the percentage of binding after long and fixed dissociation time. In a first application, we compared the antibodies elicited by two different commercially available vaccines and we showed that the binding interaction was not concentration dependent as, highly different levels were reached when injecting identical antibody concentration. No statistical significant difference was observed between both vaccines. Research firstly focused on the decrease of the non-specific binding and we found that ionic strength was a key parameter, increasing the buffer salt concentration reduced the non-specific binding without diminishing the binding strength. The sample composition was also a key parameter and purifying the IgG allowed to decrease dramatically the undesired binding events. A second application aimed at showing the equivalence between two different antigen constructions for two antibodies population. Even if identical antigen level immobilization is a challenge, the methodology is completely suitable to perform a 2-dimensional comparison (ligand and analyte). A last application was dedicated to the comparison between D and Q-pan Flu vaccines, and results showed that there was no statistical evidence of significant differences between both vaccines. End association level correlated well with haemagglutination inhibition assay at least when serum samples were not diluted at the same antibody content. This last application also showed that throughput may be extended to more than 50 samples per 80 hours / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished

Made available in DSpace on 2014-06-11T19:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-13Bitstream added on 2014-06-13T19:55:43Z : No. of bitstreams: 1 teixeira_wfp_me_araca.pdf: 257034 bytes, checksum: 74c2e0dcd5f52341aac3382521691e4d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O objetivo deste estudo foi padronizar a reação de Imunofluorescência direta (IFD) para detecção de oocistos de Cryptosporidium parvum em amostras fecais de bezerros. Os anticorpos policlonais anti-C. parvum foram produzidos em dois coelhos adultos da raça Nova Zelândia, e titulados por meio do ensaio imuno-enzimático indireto (ELISA). A fração de imunoglobulina G (IgG) foi purificada a partir do soro do coelho imunizado, utilizando-se diálise em sulfato de amônio seguida de cromatografia em coluna de DEAE celulose e conjugação com isotiocianato de fluoresceína. Por meio da IFD padronizada, foi testada a reatividade cruzada do conjugado produzido contra outras espécies de Cryptosporidium (C. andersoni e C. serpentis) e com outros agentes etiológicos presentes em fezes de bovinos (Escherichia coli, Eimeria sp. e Candida sp.). A IFD foi comparada à microscopia com contraste de fase em solução de Sheather (MCF), avaliando a capacidade de detecção de oocistos de Cryptosporidium sp. em alíquotas de fezes de bezerro inoculadas com oocistos de C. parvum, e em amostras fecais de bezerros naturalmente infectados provenientes de 37 propriedades leiteiras da região de Araçatuba, SP. Nas amostras comprovadas como positivas, foi ainda feita uma análise semi-quantitativa de oocistos de Cryptosporidium sp., visualizados por campo de microscopia em ambas as técnicas. O conjugado anti-C. parvum apresentou reatividade com C. andersoni e C. serpentis. A IFD foi utilizada com sucesso para detecção de oocistos de C. parvum em fezes de bezerros, apresentando sensibilidade para detecção de até 104 oocistos em 3 g de fezes. Entre as 300 amostras fecais de bezerros naturalmente infectados, 19,67% (59/300) foram positivas para a presença de oocistos de Cryptosporidium sp. pela IFD, apresentando diferença estatisticamente significante (p<0.05) em relação às amostras positivas pela MCF / The objective of this experiment was to standardize the direct immunofluorescence assay (DIF) for detection of Cryptosporidium parvum oocysts in fecal samples of calves. The anti-C. parvum polyclonal antibodies were produced in two adult rabbits of New Zealand breed, and titrated by an indirect enzyme-linked immunosorbent (ELISA). The immunoglobulin G (IgG) was purified from the serum of immunized rabbits by dialysis in ammonium sulfate followed by column chromatography on DEAE cellulose, and conjugated with fluorescein isothiocyanate. Using DIF the anti-C. parvum conjugate was tested for the presence of cross-reactivity against other species of Cryptosporidium (C. andersoni and C. serpentis), and other infectious agents present in cattle fecal samples (Escherichia coli, Eimeria sp. and Candida sp.). A comparison between the DIF and phase contrast microscopy in Sheather solution (MCF) was accomplished for evaluation of the efficiency of both techniques for detection of Cryptosporidium sp. oocysts in fecal samples of calves seeded with C. parvum oocysts, and in fecal samples from naturally infected calves from 37 dairy farms in the region of Araçatuba, SP. A semi-quantitative analysis of Cryptosporidium sp. oocysts per microscopic field was accomplished for both techniques. The anti-C. parvum conjugate showed cross-reactivity with C. andersoni and C. serpentis oocysts. The DIF has been used successfully in the detection of C. parvum oocysts in fecal samples of calves, with sensitivity for detecting 104 oocysts in 3 g of fecal samples. Among the 300 fecal samples from naturally infected calves, 19.67% (59/300) were positive for Cryptosporidium oocysts by DIF, with significant statistical difference (p <0.05) when compared to the number of positive samples by MCF

Resumo: O objetivo deste estudo foi padronizar a reação de Imunofluorescência direta (IFD) para detecção de oocistos de Cryptosporidium parvum em amostras fecais de bezerros. Os anticorpos policlonais anti-C. parvum foram produzidos em dois coelhos adultos da raça Nova Zelândia, e titulados por meio do ensaio imuno-enzimático indireto (ELISA). A fração de imunoglobulina G (IgG) foi purificada a partir do soro do coelho imunizado, utilizando-se diálise em sulfato de amônio seguida de cromatografia em coluna de DEAE celulose e conjugação com isotiocianato de fluoresceína. Por meio da IFD padronizada, foi testada a reatividade cruzada do conjugado produzido contra outras espécies de Cryptosporidium (C. andersoni e C. serpentis) e com outros agentes etiológicos presentes em fezes de bovinos (Escherichia coli, Eimeria sp. e Candida sp.). A IFD foi comparada à microscopia com contraste de fase em solução de Sheather (MCF), avaliando a capacidade de detecção de oocistos de Cryptosporidium sp. em alíquotas de fezes de bezerro inoculadas com oocistos de C. parvum, e em amostras fecais de bezerros naturalmente infectados provenientes de 37 propriedades leiteiras da região de Araçatuba, SP. Nas amostras comprovadas como positivas, foi ainda feita uma análise semi-quantitativa de oocistos de Cryptosporidium sp., visualizados por campo de microscopia em ambas as técnicas. O conjugado anti-C. parvum apresentou reatividade com C. andersoni e C. serpentis. A IFD foi utilizada com sucesso para detecção de oocistos de C. parvum em fezes de bezerros, apresentando sensibilidade para detecção de até 104 oocistos em 3 g de fezes. Entre as 300 amostras fecais de bezerros naturalmente infectados, 19,67% (59/300) foram positivas para a presença de oocistos de Cryptosporidium sp. pela IFD, apresentando diferença estatisticamente significante (p<0.05) em relação às amostras positivas pela MCF / Abstract: The objective of this experiment was to standardize the direct immunofluorescence assay (DIF) for detection of Cryptosporidium parvum oocysts in fecal samples of calves. The anti-C. parvum polyclonal antibodies were produced in two adult rabbits of New Zealand breed, and titrated by an indirect enzyme-linked immunosorbent (ELISA). The immunoglobulin G (IgG) was purified from the serum of immunized rabbits by dialysis in ammonium sulfate followed by column chromatography on DEAE cellulose, and conjugated with fluorescein isothiocyanate. Using DIF the anti-C. parvum conjugate was tested for the presence of cross-reactivity against other species of Cryptosporidium (C. andersoni and C. serpentis), and other infectious agents present in cattle fecal samples (Escherichia coli, Eimeria sp. and Candida sp.). A comparison between the DIF and phase contrast microscopy in Sheather solution (MCF) was accomplished for evaluation of the efficiency of both techniques for detection of Cryptosporidium sp. oocysts in fecal samples of calves seeded with C. parvum oocysts, and in fecal samples from naturally infected calves from 37 dairy farms in the region of Araçatuba, SP. A semi-quantitative analysis of Cryptosporidium sp. oocysts per microscopic field was accomplished for both techniques. The anti-C. parvum conjugate showed cross-reactivity with C. andersoni and C. serpentis oocysts. The DIF has been used successfully in the detection of C. parvum oocysts in fecal samples of calves, with sensitivity for detecting 104 oocysts in 3 g of fecal samples. Among the 300 fecal samples from naturally infected calves, 19.67% (59/300) were positive for Cryptosporidium oocysts by DIF, with significant statistical difference (p <0.05) when compared to the number of positive samples by MCF / Orientador: Marcelo Vasconcelos Meireles / Coorientador: Cáris Maroni Nunes / Banca: Ricardo Velludo Gomes de Soutello / Banca: Luzia Helena Queiroz / Mestre

Made available in DSpace on 2014-08-20T13:32:45Z (GMT). No. of bitstreams: 1 dissertacao_juliana_alcoforado_diniz.pdf: 1026827 bytes, checksum: f7e6dae0a1eabce2f815ea02d01d8e6a (MD5) Previous issue date: 2012-09-12 / Leptospirosis is a zoonosis caused by bacteria of the Leptospira genus. In recent years, efforts to identify immunogenic components of leptospires have resulted in the characterization of several outer membrane lipoproteins that are expressed during infection. Previously, our group had produced polyclonal IgY antibodies against whole-cell leptospires strain Fiocruz L1-130, which were used in different forms of capture ELISAs. In this study we produced and characterized IgY antibodies against LipL32 in recombinant form (rLipL32), the most abundant lipoprotein in the proteome of pathogenic leptospires, in order to use they in diagnostic assays and prophylaxis of leptospirosis. For this, two 22-week-old hens were immunized on day 0 with rLipL32 and oil adjuvant by intramuscular route. Three booster immunizations on days 14, 28 and 42 were held, and the eggs were collected daily from day 45. The yolks were processed and the antibodies purified with polyethylene glycol, and monitored by SDS-PAGE. Specificity of purified antibodies was assessed through indirect ELISA and Western blot (WB) using both rLipL32 and whole-cell Fiocruz L1-130. After standardization of the first batch of IgY, antibodies were conjugated with horseradish peroxidase and fluorescein (FITC). In addition, we conducted a passive immunoprotection assay in hamster model, using homologous and heterologous challenge. SDS-PAGE confirmed the successful purification of IgY and a batch with a concentration of 13μg.μL-1 was stored at -20ºC until use. Both IgY and IgY conjugated with horseradish peroxidase recognized the recombinant and native protein in ELISA and WB. In this study we produced and characterized successfully IgY against rLipL32. Although these antibodies have not been tested with clinical samples from humans or animals, they have antigen detecting potential for use in the diagnosis of leptospirosis. / A leptospirose é uma zoonose causada por bactérias do gênero Leptospira. Nos últimos anos, esforços para a identificação de componentes imunogênicos nas leptospiras resultaram na caracterização de várias lipoproteínas de membrana externa que são expressas durante a infecção. Anteriormente, nosso grupo havia produzido IgY contra Leptospira interrogans cepa Fiocruz L1-130 inteira, a qual foi usada em diferentes formatos de ELISA de captura. No presente estudo, objetivamos produzir e caracterizar anticorpos IgY contra a proteína LipL32 na forma recombinante (rLipL32), a lipoproteína mais abundante no proteoma das leptospiras patogênicas, com intuito de utilizá-los posteriormente, no diagnóstico e na imunoprofilaxia da leptospirose. Para isso, duas galinhas com 22 semanas de idade foram imunizadas no dia 0 com rLipL32 e adjuvante oleoso, através da via intramuscular. Três outras imunizações foram realizadas nos dias 14, 28 e 42 e os ovos coletados diariamente a partir do dia 45. Os anticorpos foram obitidos através do processamento das gemas, purificados com polietilenoglicol e monitorados por SDS-PAGE. A especificidade dos anticorpos foi avaliada através de ELISA indireto e Western blot (WB), ambos utilizando rLipL32 e Fiocruz L1-130 inteira. Após a padronização do primeiro lote de IgY, os anticorpos foram conjugados com peroxidase e fluoresceína (FITC), e avaliados em um ensaio de imunização passiva em hamsters, com desafio homólogo e heterólogo. O SDS-PAGE confirmou o sucesso de purificação, e um lote de IgY com a concentração de 13μg.μL-1 foi estocado a -20ºC até o uso. A IgY pura e conjugada com peroxidase reagiram com as proteínas recombinante e nativa no ELISA e no WB. Nesse estudo, produzimos e caracterizamos com sucesso IgY contra rLipL32. Embora esses anticorpos não tenham sido testados com amostras clínicas de humanos e animais, eles possuem potencial para compor ensaios que visem a detecção do antígeno no diagnóstico da leptospirose.

No description available.

With the full sequence of the human genome now available, anexciting era in biomedical research has started. The sequenceprovides information about all our genes and greatly increasesthe scope to compare genetic activities in different cells, toanalyze genetic variation between individuals and betweendifferent species and, most importantly, to investigatesystematically the whole genome in a gene-by-gene manner, andthus increase our understanding of gene function. This thesis describes studies in which developments weremade in several areas of functional genomics. Messenger RNAlevels were analyzed by the use of an amplification procedure,in which the 3´-ends of the transcripts were selected inorder to amplify the mRNA population in an unbiased fashion. Bysonicating cDNA originating from expressed mRNA, uniformlysized representatives of the transcripts,“signaturetags”, were obtained. The mRNA levels in the original mRNApopulation correlated well with the levels in the amplifiedmaterial, as verified by microarray analysis and realtimequantitative PCR. The expressed transcripts can be identifiedusing pyrosequencing, by comparing the obtained sequenceinformation from the signature tags to information contained invarious sequence databases. In one of the articles, the use ofpyrosequencing is illustrated by efforts to find genes involvedin the disease progression of atherosclerosis. More challenging than the study of mRNA levels is to analyzewhen, where and how proteins fulfill their wide-ranging rolesin all the various cellular processes. Proteins are morecomplex biomolecules than mRNA, each having unique properties.Current techniques for studying proteins need much improvement,and are often limited to investigations of a specific portionof the proteome. One approach for studying the whole proteomeis to systematically generate reagents with specific affinityfor the proteins encoded by the genome, one by one. Theaffinity reagents can be used as flags for their targets,providing a flag-specific detection system, so that the targetproteins can be sub-cellularly localized in the majority ofhuman tissues in an array format. One of the articles includedin the thesis presents a pilot project for large-scale affinityreagent production. The aim was to provide a sound basis forwhole proteome studies, but as a pilot study this investigationwas limited to the proteins encoded by human chromosome 21. Allputative genes on the chromosome were subjected to antibodygeneration in a systematic manner. Small, uniform, and easilyproduced representative portions of the full-length proteinswere expressed. These were denoted“Protein EpitopeSignature Tags”and were designed to be unique for theirfull-length counterparts. The antibodies were produced inrabbits and two of the articles in the thesis discuss differentapproaches for affinity purification of the antibodies toachieve the highest possible specificity towards the targets.The resulting“mono-specific”, but still“multi-epitope”, antibodies can be used for a widerange of additional biochemical studies, such as protein arrayand protein pull-out analyses. <b>Keywords:</b>functional genomics, 3´-end signaturetags, pyrosequencing, amplification, PrEST, chromosome 21,polyclonal antibodies, dual expression, affinitypurification.