Os autores desejam reconhecer a assistência técnica da Banes Michelle, assim como Dr. Petrie-Hanson Eels, Dr. Timothy Brown e por sua assistência em desenvolvimento e realização da imuno-histoquímica. Este projeto foi financiado pelo USDA CRIS projeto # MISV-0801310 e pela Mississippi State University College of Veterinary Medicine.

<html> 1. Desafio bacteriana <ol><li> Bactérias crescem durante a noite a 30 ° C em agitação caldo cérebro-coração. </li><li> Parar a circulação da água nos tanques de peixe e adicione o caldo na concentração de 1 em 100 (10 ml por litro, por exemplo). </li><li> Após uma hora de incubação, reinicie circulação de água nos tanques para lavar as bactérias remanescentes. </li></ol> 2. Amostragem <ol><li> Tempos de amostragem e órgãos depende do objectivo do estudo, mas em nosso estudo, foram utilizados os pontos de amostragem: 1, 6, 16, 24, 36, 48, 60, 72, 96, 110, 125 e 175 horas pós-infecção . </li><li> Pontos em cada tempo, euthanize seis peixes por imersão em água contendo MS222 e amostra os seguintes órgãos (seleção dos órgãos amostrados foi baseado no que é conhecido do processo de infecção): brânquias, músculos posteriores ao longo da linha lateral, intestino, baço, estômago, fígado, coração, rins, cabeça, tronco e rim. </li><li> Após a amostragem, imediatamente os órgãos de carga em cassetes histológicos e mergulha-as por duas horas em 1% de formol. </li><li> Após duas horas de fixação, a transferência das cassetes de formol a 50% de etanol, onde permanecem até a incorporação. </li><li> Parafina incorporar órgãos durante a noite usando um lenço de papel-Tek VIP processador de tecido 3000 (Sakura Tek, Torrance, Califórnia) e na seção de 5m usando uma Leica RM2255 microtone (Leica Microsystems, Bannockburn, Illinois). </li></ol> 3. Seções desparafinação <ol><li> Mergulhe as seções em um cocho cheio de coloração clara de rito para cerca de 5 minutos para permitir toda a cera para dissolver. Levante a prateleira e drenar o excesso de cera solvente. </li><li> Mergulhe as seções em um segundo recipiente de clara de rito por 5 minutos. Depois de alguns usos, substituir o solvente no recipiente de primeira e alternar entre os recipientes de primeiro e segundo. </li><li> Mergulhe as seções em álcool 100% para remover a cera solvente. </li><li> Mergulhe as seções em um cocho de segundo de álcool a 100%. </li><li> Mergulhe as seções em uma calha de álcool 70%. </li><li> Mergulhe as seções em água corrente para remover todos os vestígios de álcool. </li></ol> 4. Preparação de tampão <ol><li> Prepare tampão fosfato salina por dissolução de 8,0 g NaCl, 0,2 g KCl, 1,15 g Na 2 HPO 4 e 0,2 g KH 2 PO 4 em 1 litro de água destilada e pH para 7,4. </li><li> Diluir PBS para 0.9x, adicionando 900 ml de PBS e 100 ml de água destilada. </li><li> Prepare bloqueio soro adicionando 2 ml de soro do mouse; 200 mL Triton X-100 e 500 mL BSA a 50 ml de 0.9x PBS. </li><li> Prepare 50 mM Buffered Saline Bicarbonato é preparada dissolvendo 2,1 g NaHCO 3 e 4 g de NaCl em 500 ml H 2 O destilada e titulada até pH 8.2. </li></ol> 5. Immunhistochemistry <ol><li> Reidratar seções por imersão em 0.9x PBS. </li><li> Incubar as lâminas por 30 minutos no bloqueio de soro. </li><li> Incubar seções Ed9 (diluída 1 em 100 no soro bloqueio) por duas horas em uma câmara úmida opaca à temperatura ambiente. </li><li> Enxágüe seções 4 vezes em PBS por 10 minutos cada. </li><li> Incubar seções por duas horas em 50 ul do anticorpo secundário (cabra anticorpos anti rato FITC; diluídas 500 vezes no bloqueio de soro) em uma câmara úmida opaca à temperatura ambiente. </li><li> Enxágüe seções 3 vezes em solução salina de bicarbonato. </li><li> Enxágüe seções brevemente em água deionizada. </li></ol> 6. Montagem <ol><li> Deixe os slides para secar na escuridão por alguns minutos. </li><li> A montagem é realizada utilizando permafluor. </li><li> Deixar o meio de montagem para secar, preferencialmente durante a noite, em um ambiente escuro e fresco. </li></ol> 7. Microscópio <ol><li> Cortes histológicos estão prontos para observar em um microscópio fluorescente. Em nosso experimento, usamos uma Olympus BX51 microscópio equipado com um triplo (FITC; MCA-Texas Red) filtro. O software Picture Frame (MicroFire, Goleta, Califórnia) foi utilizado. </li></ol> 8. Resultados representativos: Porque a auto-fluorescência de tecidos de peixes é tão alta, estes tecidos aparecerá laranja sob o Tri-filtro, convenientemente fornecendo um fundo para as bactérias. Neste contexto, o indivíduo FITC bactérias coradas vai aparecer como pontos verdes brilhantes e, ao 200X sua forma vara será reconhecível (Fig. 1). Seções ruim pode constituir falsos positivos (devido a um problema na fase de enxaguamento), caso em que um grande número de bactérias parecem estar presentes de maneira uniforme no slide. <img src="/files/ftp_upload/2687/2687fig1.jpg" alt="Figura 1"/> Figura 1. Micrografia de um músculo mostrando duas seções E. ictaluri (setas a e b) (200x). IGURA 2 &quot;/&gt; Figura 2. Esquema geral do experimento

<ol>
	<li>Plumb, J. A., Woo, P. T. K., Bruno, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fish Diseases and Disorders. , 479-479 (1998).</li><li>Roberts, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fish Pathology. , (2001).</li><li>Lawrence, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Louisiana State University. , (1997).</li><li>Nusbaum, K. E., Morrisson, E. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Entry+of+35S-Labeled+Edwardsiella+ictaluri+into+Channel+Catfish.">Entry of 35S-Labeled Edwardsiella ictaluri into Channel Catfish.</a> Journal of Aquatic Animal Health. 8, 146-146 (1996).</li><li>Karsi, A., Menanteau-Ledouble, S., Lawrence, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+bioluminescent+Edwardsiella+ictaluri+for+noninvasive+disease+monitoring.">Development of bioluminescent Edwardsiella ictaluri for noninvasive disease monitoring.</a> FEMS Microbiology Letters. 260, 286-286 (2006).</li><li>Miyazaki, T., Plumb, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histopathology+of+Edwardsiella+ictaluri+in+channel+catfish,+Ictalurus+punctatus+(Rafinesque).">Histopathology of Edwardsiella ictaluri in channel catfish, Ictalurus punctatus (Rafinesque).</a> Journal of Fish Diseases. 8, 839-839 (1985).</li><li>Areechon, N., Plumb, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogenesis+of+Edwardsiella+ictaluri+in+Channel+Catfish,+Ictalurus+punctatus.">Pathogenesis of Edwardsiella ictaluri in Channel Catfish, Ictalurus punctatus.</a> Journal of the World Mariculture Society. 14, 249-249 (1983).</li><li>Dumpala, P. R., Lawrence, M. L., Karsi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Proteome+analysis+of+Edwardsiella+ictaluri.">Proteome analysis of Edwardsiella ictaluri.</a> Proteomics. 9, 1353-1353 (2009).</li><li>Thune, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Signature-Tagged+Mutagenesis+of+Edwardsiella+ictaluri+Identifies+Virulence-Related+Genes,+Including+a+Salmonella+Pathogenicity+Island+2+Class+of+Type+III+Secretion+Systems.">Signature-Tagged Mutagenesis of Edwardsiella ictaluri Identifies Virulence-Related Genes, Including a Salmonella Pathogenicity Island 2 Class of Type III Secretion Systems.</a> Applied and Environmental Microbiology. 73, 7934-7934 (2007).</li><li>Karsi, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-throughput+bioluminescence+mutant+screening+strategy+for+identification+of+bacterial+virulence+genes.">High-throughput bioluminescence mutant screening strategy for identification of bacterial virulence genes.</a> Applied and Environmental Microbiology. 75, 2166-2166 (2009).</li><li>Hook, E. W., Mandell, G. L., Douglas, G., Bennett, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Principles and Practices of Infectious Diseases. , 1700-1700 (1990).</li><li>Ainsworth, J., Capley, G., Waterstreet, P., Munson, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+monoclonal+antibodies+in+the+indirect+fluorescent+antibody+technique+(IFA)+for+the+diagnosis+of+Edwardsiella+ictaluri.">Use of monoclonal antibodies in the indirect fluorescent antibody technique (IFA) for the diagnosis of Edwardsiella ictaluri.</a> Journal of Fish Diseases. 9, 439-439 (1986).</li></ol>

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Este protocolo de detalhes de uma técnica para a visualização em situ do bagre patógeno Edwardsiella ictaluri em cortes histológicos. O melhor de nosso conhecimento, este é o primeiro protocolo, tais descrito. O passo mais crítico, em nossa experiência, é a lavagem dos anticorpos, tal como descrito no passo 4.4 do presente protocolo como a lavagem insuficiente pode resultar em falso positivo. O principal problema com interpretação dos...

<table border="1"><tbody><tr><th> Nome do reagente </th><th> Companhia </th><th> Número de catálogo </th></tr><tr><td> Caldo cérebro </td><td> Becton Dickinson </td><td> 237200 </td></tr><tr><td> MS222 </td><td> Argent Labs </td><td></td></tr><tr><td> Soro do mouse toda </td><td> Cappel </td><td> 55989 </td></tr><tr><td> Cabra anti-rato-FITC </td><td> Sul Biotech </td><td> 1010-1004 </td></tr><tr><td> Permafluor </td><td> Laboratório de Visão </td><td> Ta-030-FM </td></tr><tr><td> Cloreto de potássio (KCl) </td><td> Sigma </td><td> P-4504 </td></tr><tr><td> Triton-X </td><td> Sigma-Aldrich </td><td> X100 6X500ML- </td></tr><tr><td> Albumina de soro bovino </td><td> Sigma </td><td> 85040C </td></tr><tr><td> Fosfato de potássio (KH 2 PO 4) </td><td> Sigma </td><td> P-5379 </td></tr><tr><td> Bicarbonato de sódio (NaHCO 3) </td><td> Sigma </td><td> S-5761 </td></tr><tr><td> Cloreto de sódio (Nacala) </td><td> Sigma </td><td> S-9625 </td></tr><tr><td> Fosfato de sódio dibásico (Na 2 HPO 4) </td><td> Sigma </td><td> S-9390 </td></tr></tbody></table>

use of fluorescent immuno-chemistry for the detection of edwardsiella ictaluri in channel catfish (i. punctatus) samples

Enquanto Edwardsiella ictaluri é um importante patógeno do canal catfish Ictalurus punctatus e foi descoberto há quase três décadas 1,2, até agora, a melhor do conhecimento desses autores, nenhum método foi desenvolvido para permitir a visualização em situ do bactérias em cortes histológicos. Enquanto a localização bacteriana foi determinada in vivo em estudos anteriores usando contagem placa 3, 4 radiométrica rotulados ou bactérias bioluminescentes 5, a maioria destes estudos só foram realizados ao nível de órgãos bruto, com uma exceção 6. Esta limitação é particularmente preocupante porque E. ictaluri tem um complexo ciclo de infecção 1,7, e tem uma variedade de fatores de virulência 8,9. A complexa interação de E. ictaluri com a sua variedade é semelhante em muitos aspectos, a Salmonella typhi 10, que está na mesma família taxonômica. Aqui nós descrevemos uma técnica que permite a detecção de bactérias usando indireta imuno-histoquímica, usando o anticorpo monoclonal Ed9 descrita por Ainsworth et al. 11. Resumidamente, um soro de bloqueio é aplicada a inclusão em parafina os cortes histológicos para prevenir não-específicas de licitação. Então, as seções são incubadas com o anticorpo primário: E. ictaluri anticorpo monoclonal específico Ed9. Anticorpos em excesso são lavados afastado eo FITC anticorpos secundários são adicionados. Após a lavagem, as seções são montadas com um meio específico fluorescentes de montagem. Isso permitiu a detecção de E. ictaluri in situ em cortes histológicos de tecidos bagre do canal.

Watch this Scientific Journal Video about Use of Fluorescent Immuno-Chemistry for the detection of Edwardsiella ictaluri in channel catfish I. punctatus samples at JoVE.com

Use of Fluorescent Immuno-Chemistry for the detection of Edwardsiella ictaluri in channel catfish I. punctatus samples

Aqui nós descrevemos um procedimento que permita a rotulagem de<em&gt; Edwardsiella ictaluri in situ</em&gt; Em cortes histológicos de bagre do canal<em&gt; Ictalurus punctatus</em&gt; Usando imunohistoquímica indireta com anticorpos monoclonais Ed9 como primária, e fluorescente FITC anticorpos rotulado como um secundário. Isso permitiu a detecção da bactéria por microscopia de fluorescência.

Uso de fluorescentes Imuno-Química para a detecção de Edwardsiella ictaluri Em bagre do canal ( I. punctatus) Amostras

While Edwardsiella ictaluri is a major pathogen of channel catfish Ictalurus punctatus and has been discovered nearly 
three decades ago 1,2, so far, to ...

use-fluorescent-immuno-chemistry-for-detection-edwardsiella-ictaluri

Research

JoVE Journal

Immunology and Infection

Use of Fluorescent Immuno-Chemistry for the detection of Edwardsiella ictaluri in channel catfish (I. punctatus) samples

10.4K visualizações.  Mississippi State University. Aqui nós descrevemos um procedimento que permita a rotulagem de Edwardsiella ictaluri in situ Em cortes histológicos de bagre do canal Ictalurus punctatus Usando imunohistoquímica indireta com anticorpos monoclonais Ed9 como primária, e fluorescente FITC anticorpos rotulado como um secundário. Isso permitiu a detecção da bactéria por microscopia de fluorescência.

Vídeo: Use of Fluorescent Immuno-Chemistry for the detection of Edwardsiella ictaluri in channel catfish I. punctatus samples

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in situ hybridization (FISH) for rapid culture-independent detection of Salmonella spp. Cell-charged tapes can also be placed face-down on selective agar for solid-phase enrichment prior to detection. Alternatively, low-volume liquid enrichments (liquid surface miniculture) can be performed on the surface of the tape in non-selective broth, followed by FISH and analysis via flow cytometry. To begin, sterile adhesive tape is brought into contact with fresh produce, gentle pressure is applied, and the tape is removed, physically extracting microbes present on these surfaces. Tapes are mounted sticky-side up onto glass microscope slides and the sampled cells are fixed with 10% formalin (30 min) and dehydrated using a graded ethanol series (50, 80, and 95%; 3 min each concentration). Next, cell-charged tapes are spotted with buffer containing a Salmonella-targeted DNA probe cocktail and hybridized for 15 - 30 min at 55&deg;C, followed by a brief rinse in a washing buffer to remove unbound probe. Adherent, FISH-labeled cells are then counterstained with the DNA dye 4',6-diamidino-2-phenylindole (DAPI) and results are viewed using fluorescence microscopy. For solid-phase enrichment, cell-charged tapes are placed face-down on a suitable selective agar surface and incubated to allow in situ growth of Salmonella microcolonies, followed by FISH and microscopy as described above. For liquid surface miniculture, cell-charged tapes are placed sticky side up and a silicone perfusion chamber is applied so that the tape and microscope slide form the bottom of a water-tight chamber into which a small volume (&le; 500 &mu;L) of Trypticase Soy Broth (TSB) is introduced. The inlet ports are sealed and the chambers are incubated at 35 - 37&deg;C, allowing growth-based amplification of tape-extracted microbes. Following incubation, inlet ports are unsealed, cells are detached and mixed with vigorous back and forth pipetting, harvested via centrifugation and fixed in 10% neutral buffered formalin. Finally, samples are hybridized and examined via flow cytometry to reveal the presence of Salmonella spp. As described here, our "tape-FISH" approach can provide simple and rapid sampling and detection of Salmonella on tomato surfaces. We have also used this approach for sampling other types of fresh produce, including spinach and jalape&ntilde;o peppers.

Combination of Adhesive-tape-based Sampling and Fluorescence in situ Hybridization for Rapid Detection of Salmonella on Fresh Produce

This protocol describes a simple adhesive-tape-based approach for sampling of tomato and other fresh produce surfaces, followed by rapid whole cell detection of Salmonella using fluorescence in situ hybridization (FISH).

Combinação de adesivos de fita baseada em amostragem e de fluorescência In situ Hibridação para detecção rápida de Salmonella On Fresh Produce

This protocol describes a simple approach for adhesive-tape-based sampling of tomato and other fresh produce surfaces, followed by on-tape fluorescence in ...

Imunologia e Infecção

Multiplex Detection of Bacteria in Complex Clinical and Environmental Samples using Oligonucleotide-coupled Fluorescent Microspheres

Bacterial vaginosis (BV) is a recurring polymicrobial syndrome that is characterized by a change in the "normal" microbiota from Lactobacillus-dominated to a microbiota dominated by a number of bacterial species, including Gardnerella vaginalis, Atopobium vaginae, and others1-3. This condition is associated with a range of negative health outcomes, including HIV acquisition4, and it can be difficult to manage clinically5. Furthermore, diagnosis of BV has relied on the use of Gram stains of vaginal swab smears that are scored on various numerical criteria6,7. While this diagnostic is simple, inexpensive, and well suited to resource-limited settings, it can suffer from problems related to subjective interpretations and it does not give a detailed profile of the composition of the vaginal microbiota8. Recent deep sequencing efforts have revealed a rich, diverse vaginal microbiota with clear differences between samples taken from individuals that are diagnosed with BV compared to those individuals that are considered normal9,10, which has resulted in the identification of a number of potential targets for molecular diagnosis of BV11,12. These studies have provided a wealth of useful information, but deep sequencing is not yet practical as a diagnostic method in a clinical setting. We have recently described a method for rapidly profiling the vaginal microbiota in a multiplex format using oligonucleotide-coupled fluorescent beads with detection on a Luminex platform13. This method, like current Gram stain-based methods, is rapid and simple but adds the additional advantage of exploiting molecular knowledge arising from sequencing studies in probe design. This method therefore provides a way to profile the major microorganisms that are present in a vaginal swab that can be used to diagnose BV with high specificity and sensitivity compared to Gram stain while providing additional information on species presence and abundance in a semi-quantitative and rapid manner. This multiplex method is expandable well beyond the range of current quantitative PCR assays for particular organisms, which is currently limited to 5 or 6 different assays in a single sample14. Importantly, the method is not limited to the detection of bacteria in vaginal swabs and can be easily adapted to rapidly profile nearly any microbial community of interest. For example, we have recently begun to apply this methodology to the development of diagnostic tools for use in wastewater treatment plants.

We describe a multiplex method for the detection of microorganisms within a sample using oligonucleotide-coupled fluorescent beads. Amplicon from all organisms within a sample is hybridized to a panel of probe-coupled beads. A Luminex or Bio-Plex instrument is used to query each bead for bead type and hybridization signal.

Detecção de multiplex de bactérias em amostras clínicas e Complexo Ambiental utilizando Oligonucleotídeos-coupled microesferas fluorescentes

Bacterial vaginosis (BV) is a recurring polymicrobial syndrome that is characterized by a change in the "normal" microbiota from Lactobacillus-dominated ...

Detection of Fluorescent Nanoparticle Interactions with Primary Immune Cell Subpopulations by Flow Cytometry

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable method of analysis by flow cytometry to study nanoparticle interaction with immune cells. Primary immune cells can be easily purified from human or mouse tissues by antibody-mediated magnetic isolation. In the first instance, the different cell populations running in a flow cytometer can be distinguished by the forward-scattered light (FSC), which is proportional to cell size, and the side-scattered light (SSC), related to cell internal complexity. Furthermore, fluorescently labeled antibodies against specific cell surface receptors permit the identification of several subpopulations within the same sample. Often, all these features vary when cells are boosted by external stimuli that change their physiological and morphological state. Here, 50 nm FITC-SiO2 nanoparticles are used as a model to identify the internalization of nanostructured materials in human blood immune cells. The cell fluorescence and side-scattered light increase after incubation with nanoparticles allowed us to define time and concentration dependence of nanoparticle-cell interaction. Moreover, such protocol can be extended to investigate Rhodamine-SiO2 nanoparticle interaction with primary microglia, the central nervous system resident immune cells, isolated from mutant mice that specifically express the Green Fluorescent Protein (GFP) in the monocyte/macrophage lineage. Finally, flow cytometry data related to nanoparticle internalization into the cells have been confirmed by confocal microscopy.

Analysis of nanoparticle interaction with defined subpopulations of immune cells by flow cytometry.

Detecção de nanopartículas fluorescentes Interações com Primário imunitário subpopulações de células por citometria de fluxo

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable ...

The Use of Fluorescent Target Arrays for Assessment of T Cell Responses In vivo

The ability to monitor T cell responses in vivo is important for the development of our understanding of the immune response and the design of immunotherapies. Here we describe the use of fluorescent target array (FTA) technology, which utilizes vital dyes such as carboxyfluorescein succinimidyl ester (CFSE), violet laser excitable dyes (CellTrace Violet: CTV) and red laser excitable dyes (Cell Proliferation Dye eFluor 670: CPD) to combinatorially label mouse lymphocytes into &#62;250 discernable fluorescent cell clusters. Cell clusters within these FTAs can be pulsed with major histocompatibility (MHC) class-I and MHC class-II binding peptides and thereby act as target cells for CD8+ and CD4+ T cells, respectively. These FTA cells remain viable and fully functional, and can therefore be administered into mice to allow assessment of CD8+ T cell-mediated killing of FTA target cells and CD4+ T cell-meditated help of FTA B cell target cells in real time in vivo by flow cytometry. Since &#62;250 target cells can be assessed at once, the technique allows the monitoring of T cell responses against several antigen epitopes at several concentrations and in multiple replicates. As such, the technique can measure T cell responses at both a quantitative (e.g.&#160;the cumulative magnitude of the response) and a qualitative (e.g.&#160;functional avidity and epitope-cross reactivity of the response) level. Herein, we describe how these FTAs are constructed and give an example of how they can be applied to assess T cell responses induced by a recombinant pox virus vaccine.

The Use of Fluorescent Target Arrays for Assessment of T Cell Responses In vivo

The ability to monitor T cell responses in detail in vivo is important for the development of our understanding of the immune response. Here we describe the use of fluorescent target arrays (FTAs) in an in vivo T cell assay that assesses &#62;250 parameters simultaneously by flow cytometry.

O Uso de fluorescentes alvo Matrizes para a Avaliação de respostas de células T<em&gt; In vivo</em

The ability to monitor T cell responses in vivo is important for the development of our understanding of the immune response and the design of ...

Magnetic Stirrer Method for the Detection of Trichinella Larvae in Muscle Samples

Trichinellosis is a debilitating disease in humans and is caused by the consumption of raw or undercooked meat of animals infected with the nematode larvae of the genus Trichinella. The most important sources of human infections worldwide are game meat and pork or pork products. In many countries, the prevention of human trichinellosis is based on the identification of infected animals by means of the artificial digestion of muscle samples from susceptible animal carcasses.
There are several methods based on the digestion of meat but the magnetic stirrer method is considered the gold standard. This method allows the detection of Trichinella larvae by microscopy after the enzymatic digestion of muscle samples and subsequent filtration and sedimentation steps. Although this method does not require special and expensive equipment, internal controls cannot be used. Therefore, stringent quality management should be applied throughout the test. The aim of the present work is to provide detailed handling instructions and critical control points of the method to analysts, based on the experience of the European Union Reference Laboratory for Parasites and the National Reference Laboratory of Germany for Trichinella.

Magnetic Stirrer Method for the Detection of Trichinella Larvae in Muscle Samples

The prevention of human trichinellosis in many countries worldwide is based on the laboratory examination of muscle samples from susceptible animals by methods of digestion, of which the magnetic stirrer method is considered the gold standard.

Método agitador magnético para Detecção de<em&gt; Trichinella</em&gt; As larvas em amostras de músculo

Trichinellosis is a debilitating disease in humans and is caused by the consumption of raw or undercooked meat of animals infected with the nematode ...

Rapid, Safe, and Simple Manual Bedside Nucleic Acid Extraction for the Detection of Virus in Whole Blood Samples

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for the rapid bedside inactivation of the Ebola virus during blood sampling for safe nucleic acid (NA) tests by adding a commercial lysis/binding buffer directly into the vacuum blood collection tubes. Using this bedside inactivation approach, we have developed a safe, rapid, and simplified bedside NA extraction method for the subsequent detection of a virus in lysis/binding buffer-inactivated whole blood. The NA extraction is directly performed in the blood collection tubes and requires no equipment or electricity. 
After the blood is collected into the lysis/binding buffer, the contents are mixed by flipping the tube by hand, and the mixture is incubated for 20 min at room temperature. Magnetic glass particles (MGPs) are added to the tube, and the contents are mixed by flipping the collection tube by hand. The MGPs are then collected on the side of the blood collection tube using a magnetic holder or a magnet and a rubber band. The MGPs are washed three times, and after the addition of elution buffer directly into the collection tube, the NAs are ready for NA tests, such as qPCR or isothermal loop amplification (LAMP), without the removal of the MGPs from the reaction. The NA extraction method is not dependent on any laboratory facilities and can easily be used anywhere (e.g., in field hospitals and hospital isolation wards). When this NA extraction method is combined with LAMP and a portable instrument, a diagnosis can be obtained within 40 min of the blood collection.

Here, we present a protocol for the rapid virus nucleic acid extraction from the virus-inactivated whole blood. The extraction is performed directly in the blood collection tubes and requires no equipment or electricity. The method is not dependent on laboratory facilities and can be used anywhere (e.g., in field hospitals).

Extração rápida, segura e simples Manual cabeceira de ácidos nucleicos para a detecção de vírus em amostras de sangue total

The rapid diagnosis of an infection is essential for the outbreak management, risk containment, and patient care. We have previously shown a method for ...

A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.

Fecal-oral transmission of acute gastroenteritis occurs from time to time, especially when people who handled food and water are infected by Salmonella spp./Shigella spp. The gold standard method for the detection of Salmonella spp./Shigella spp. is direct culture but this is labor-intensive and time-consuming. Here, we describe a high-throughput platform for Salmonella spp./Shigella spp. screening, using real-time polymerase chain reaction (PCR) combined with guided culture. There are two major stages: real-time PCR and the guided culture. For the first stage (real-time PCR), we explain each step of the method: sample collection, pre-enrichment, DNA extraction and real-time PCR. If the real-time PCR result is positive, then the second stage (guided culture) is performed: selective culture, biochemical identification and serological characterization. We also illustrate representative results generated from it. The protocol described here would be a valuable platform for the rapid, specific, sensitive and high-throughput screening of Salmonella spp./Shigella spp.

A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.

Salmonella spp./Shigella spp. are common pathogens attributed to diarrhea. Here, we describe a high-throughput platform for the screening of Salmonella spp./Shigella spp. using real-time PCR combined with guided culture.

Uma plataforma de alto rendimento para o rastreio de Salmonella spp. /Shigella spp.

Fecal-oral transmission of acute gastroenteritis occurs from time to time, especially when people who handled food and water are infected by Salmonella ...

Multiplexed Fluorescent Immunohistochemical Staining, Imaging, and Analysis in Histological Samples of Lymphoma

Immunohistochemical (IHC) methods for the in-situ analysis of protein expression by light microscopy are a powerful tool for both research and diagnostic purposes. However, the visualization and quantification of multiple antigens in a single tissue section using conventional chromogenic IHC is challenging. Multiplexed imaging is especially relevant in lymphoma research and diagnostics, where markers have to be interpreted in the context of a complex tumor microenvironment. Here we describe a protocol for multiplexed fluorescent IHC staining to enable the quantitative assessment of multiple targets in specific cell types of interest in lymphoma.The method covers aspects of antibody validation, antibody optimization, the multiplex optimization with markers of lymphoma subtypes, the staining of tissue microarray (TMA) slides, and the scanning of the slides, followed by data analysis, with specific reference to lymphoma. Using this method, scores for both the mean intensity of a marker of interest and the percentage positivity are generated to facilitate further quantitative analysis. Multiplexing minimizes sample utilization and provides spatial information for each marker of interest.

Here we describe a protocol for multiplex fluorescent immunohistochemical staining and imaging for the simultaneous localization of multiple cancer-associated antigens in lymphoma. This protocol can be extended to the colocalization analysis of biomarkers within all tissue sections.

Coloração imuno-histoquímica fluorescente multiplexada, imagem e análise de amostras histológicas de linfoma

Immunohistochemical (IHC) methods for the in-situ analysis of protein expression by light microscopy are a powerful tool for both research and diagnostic ...

VirWaTest, A Point-of-Use Method for the Detection of Viruses in Water Samples

Viruses excreted by humans and animals may contaminate water sources and pose a risk to human health when this water is used for drinking, food irrigation, washing, etc. The classical fecal bacteria indicator does not always check for the presence of viral pathogens so the detection of viral pathogens and viral indicators is relevant in order to adopt measures of risk mitigation, especially in humanitarian scenarios and in areas where water-borne viral outbreaks are frequent.
At present, several commercial tests allowing the quantification of fecal indicator bacteria (FIB) are available for testing at the point of use. However, such commercial tests are not available for the detection of viruses. The detection of viruses in environmental water samples requires concentrating several liters into smaller volumes. Moreover, once concentrated, the detection of viruses relies on methods such as nucleic acid extraction and molecular detection (e.g., polymerase chain reaction [PCR]-based assays) of the viral genomes.
The method described here allows the concentration of viruses from 10 L water samples, as well as the extraction of viral nucleic acids at the point of use, with simple and portable equipment. This allows the testing of water samples at the point of use for several viruses and is useful in humanitarian scenarios, as well as at any context where an equipped laboratory is not available. Alternatively, the method allows concentrating viruses present in water samples and the shipping of the concentrate to a laboratory at room temperature for further analysis.

Here we present VirWaTest, which is a simple, affordable and portable method for the concentration and detection of viruses from water samples at the point of use.

VirWaTest, um método de ponto de uso para a detecção de vírus em amostras de água

Viruses excreted by humans and animals may contaminate water sources and pose a risk to human health when this water is used for drinking, food ...

Visualization of Bacterial Resistance using Fluorescent Antibiotic Probes

Fluorescent antibiotics are multipurpose research tools that are readily used for the study of antimicrobial resistance, due to their significant advantage over other methods. To prepare these probes, azide derivatives of antibiotics are synthesized, then coupled with alkyne-fluorophores using azide-alkyne dipolar cycloaddition by click chemistry. Following purification, the antibiotic activity of the fluorescent antibiotic is tested by minimum inhibitory concentration assessment. In order to study bacterial accumulation, either spectrophotometry or flow cytometry may be used, allowing for much simpler analysis than methods relying on radioactive antibiotic derivatives. Furthermore, confocal microscopy can be used to examine localization within the bacteria, affording valuable information about mode of action and changes that occur in resistant species. The use of fluorescent antibiotic probes in the study of antimicrobial resistance is a powerful method with much potential for future expansion.

Fluorescently tagged antibiotics are powerful tools that can be used to study multiple aspects of antimicrobial resistance. This article describes the preparation of fluorescently tagged antibiotics and their application to studying antibiotic resistance in bacteria. Probes can be used to study mechanisms of bacterial resistance (e.g., efflux) by spectrophotometry, flow cytometry, and microscopy.