Agradecemos Pr. Bernard La Scola para conselhos técnicos úteis e interessante discussão sobre co-cultura amebas e enriquecimento amebas. Agradecemos também o Dr. Vincent Thomas por sua ajuda na implementação da técnica em nosso laboratório.

1. Amebas Coculture 1.1 Preparação da amostra <ol><li> Amostra ambiental <ol><li> As amostras de água Filtra-se a amostra de água (500 ml a 1 litro), por meio de uma membrana de 0,22 de tamanho de poro. Em seguida, agitar a membrana nos ameba salinas PAS médias de página (120 mg de NaCl, 4 mg de MgSO4 • 7H 2 O, 4 mg de CaCl 2 • 2H 2 O, 142 mg de Na 2 HPO 4, e 136 mg de KH 2 PO 4 em 1 L de água destilada). </li><li> As amostras sólidas Ressuspender as amostras sólidas como amostras do solo de areia e de amostras semi-sólidos tais como lamas activadas em água destilada ou PBS e filtrá-las através de uma membrana de 0,22 de tamanho de poro. Em seguida, agitar a membrana em PAS. </li><li> As amostras altamente contaminadas com amebas e protozoários endógeno Primeiro sedimentar as amostras por centrifugação a baixa velocidade (180 xg) for 10 minutos ou filtra-se por uma membrana de 5 um de tamanho de poro. Além disso processar o sobrenadante (respectivamente filtrado), como descrito em 1.1.1. Nota: Outras técnicas de descontaminação pode ser usado para descontaminar mais amostras ambientais: Aquece-se a amostra a 50 ° C durante 30 min ou tratar com soluções ácidas ou básicas 14. </li></ol></li><li> Amostra clínica Processe amostras clínicas, dependendo de suas propriedades físico-químicas. Filtrar ou centrifugar líquidos para remover grandes impurezas. Ressuspender as amostras sólidas. Para usar tecidos, triturá-los, por exemplo, usando um homogeneiser dounce ou contas de vidro, e lisar as células para libertar as bactérias intracelulares. </li></ol> 1.2 Amebas preparação <ol><li> Preparação Caldo Prepare as seguintes mídias: a mídia rica contendo peptona, extrato de levedura e glicose (PYG; 100 g de protease peptona, 10 g de extrato de levedura, 4,9 g de MgSO4 • 7H 2O, 5 g de citrato de sódio • 2H 2 O, 0,1 g de Fe (NH 4) 2 (SO 4) 2 • 6H 2 O, 1,7 g de KH 2 PO 4, 1,97 g de Na 2 HPO 4 • 7H 2 O , 45 g de glicose, e 0,295 g de CaCl 2 em 5 L de água destilada) e um meio não-nutritivo tais como PAS para espécies de Acanthamoeba. </li><li> Cultura de amebas <ol><li> Cultive amebas (preferencialmente Acanthamoeba castellanii ATCC 30010 ou A. polyphaga Linc-AP1) a 25 ° C em frascos de cultura de células contendo 30 ml de meio PYG. </li><li> Recolher as amebas, por agitação vigorosa do balão e centrifugar a suspensão de células durante 10 min a 1500 x g. Lava-se a pelete duas vezes com meio PAS. Contar as células num diapositivo Kova e ajustar o volume para se obter uma suspensão de 5 x 10 5 células por ml. </li><li> Transferir a suspensão de amebas em microplacas. Use 1 ml por poço para 12 - e 24-wplacas ell, 500 ul para placas de 48 poços e 300 ul para placas de 96 poços. Incubar a microplaca durante pelo menos 2 horas a 25 ° C. Isto permite que a sedimentação e a fixação do amebas para o fundo de cada poço. </li></ol></li></ol> 1.3 Coculture <ol><li> Inoculação da amostra <ol><li> Inocular a placa a partir de 2.3.3, com uma série de diluições da amostra a partir de 1.1 ou 1.2, geralmente com 10 vezes diluições em série, começando com 100 ul de amostra não diluída. </li><li> Centrifugue a microplaca a 1.800 xg durante 10 min para sedimentar no relvado amebas os microrganismos potencialmente presentes na amostra. Isso aumenta o contato e fagocitose de microorganismos por amebas. </li><li> Incubar as placas durante 45 min a 25 ° C e lava-se três vezes com PAS, substituindo o meio com PAS fresco. Adicionar 1 ml por poço de PAS com ou sem adição de antibióticos (estreptomicina, penicilina, gentamicina e / ou vancomicina), dependendo das bactericidaespécies ai que são procurados. </li><li> Incubar a microplaca a 32 ° C numa atmosfera húmida de evitar enquistamento do amebas. Observe cada poço diariamente com um objetivo 20X para detectar a presença de bactérias invasoras e lise amebas. </li><li> No caso da lise, realizar uma subcultura em amebas fresco inoculando 100 ul de co-culturas a uma monocamada de cerca de 10 5 amebas / cm 2. Para isolar especificamente uma determinada espécie bacteriana, também inocular ágar específico projetado para estas bactérias (ou seja, ágar BCYE para Legionella spp.). </li><li> Na ausência de lise, tomar 100 ml de co-culturas de quatro a sete dias após a primeira inoculação e inocular uma cultura fresca amebas de 900 ul numa placa de 24 poços. Se a lise rápida das amebas é observada sem a proliferação de bactérias, vírus pode estar presente. Neste caso, filtrar o sobrenadante a 0,22 mM e utilizar a suspensão foi filtrada para infectar amibas fresco. </li></ol&gt; </li></ol> 1.4 isolamento e caracterização de bactérias <ol><li> Coloração bacteriana Realize coculturas diretamente em lamínulas em microplacas de 24 poços. Remover o meio e realizar coloração ou imunofluorescência. <ol><li> Coloração Romanowsky Modificado <ol><li> Deixe o lamela seca. Mergulhe a lamela cinco vezes na solução fixadora (2 mg / L Fast Green em metanol). </li><li> Imergir a lamela cinco vezes em que a solução de coloração (1,22 g / L Eosina L em tampão fosfato pH 6,6) </li><li> Finalmente, mergulhe a lamela 5 vezes na solução de coloração II (1,1 g / L tiazina em tampão fosfato pH 6.6). </li><li> Lavar a amostra com água destilada. Deixe secar e observar ao microscópio. </li></ol></li><li> Coloração de Ziehl-Neelsen <ol><li> Deixe o lamela seca. Cobrir a amostra com Ziehl fucsina. Aqueça o corante com uma chama até vapores aparecer. </li><li> Arrefece-se à temperatura ambiente durante pelo menos 5 mine enxágüe com água destilada. Cobrir a amostra com uma solução de ácido clorídrico a 3%, em isopropanol durante 2 minutos e lavar com água destilada. </li><li> Capa para 30 seg com azul de metileno e enxágüe com água destilada. Deixe secar e observar ao microscópio 22. </li></ol></li><li> Coloração Gimenez <ol><li> Prepara-se uma solução estoque de fucsina básica através da mistura de 100 ml de 10% de fucsina básica (10 g de fucsina básica em 100 ml de etanol a 95%), 250 ml de 4% de fenol aquoso e 650 ml de água destilada. Incubar a 37 ° C durante 48 horas antes da utilização. </li><li> Deixe o lamela secar e fixar por passagem através de chama. Cobrir a amostra com fucsina básica recentemente filtrada (4 ml de solução de estoque de fucsina básica em 10 ml de 0,1 M de tampão fosfato de sódio, pH 7,45) durante 2 min. </li><li> Lavar a amostra com água e incubar em verde malaquita (0,8% em água destilada) por 10 segundos. Enxágüe novamente com água e repita a coloração verde malaquita. Enxágüe novamente com água. Deixe o lamela seca, mount-lo, e observar ao microscópio 23. </li></ol></li><li> Imunofluorescência <ol><li> Fixar a lamela por incubação em metanol durante 5 min ou com paraformaldeído a 4% durante 10 min. </li><li> Lavar três vezes com PBS e incuba-se durante 2 horas em solução de bloqueio (5% BSA, 0,1% de saponina em PBS) à temperatura ambiente. </li><li> Incubar a lamela por 1 hora em solução contendo anticorpos produzidos contra o microorganismo de interesse bloqueio. </li><li> Lavar novamente três vezes em PBS e incubar durante 1 hora com um anticorpo secundário dirigido contra o anticorpo primário e ligada a um fluoróforo. Lavar três vezes com PBS, montar a lamela e observa por microscopia de fluorescência. </li></ol></li></ol></li><li> A detecção de ADN por PCR Extrair DNA de 100 a 200 ul de cocultura amebas. Detectar microorganismos com primers universais visando o gene 16S rRNA ou primers específicos para as espécies de interesse, como micobactérias 24, Legionella 25 ou membros da Chlamydiales 26. </li></ol> 2. Enriquecimento de amebas 2.1. A preparação das amostras Ressuspender amostras sólidas e semi-sólidos em PAS em vortex. Centrifugar a suspensão a baixa velocidade (180 xg) durante 10 min. Isso permite que o enriquecimento de amebas de vida livre na pelota. O sobrenadante pode ser utilizado para co-cultura amebas e o sedimento de enriquecimento amebas 21. 2.2. Preparação Médio <ol><li> Adicionar 1,5 g de agar a 100 mL de PAS e autoclave o meio de 15 min a 121 ° C. Despeje o meio quente em placas de Petri e deixar solidificar à temperatura ambiente. </li><li> Grow Escherichia coli (ATCC 25922) em meio LB ou tioglicolato de caldo durante a noite a 37 ° C. Lavar as bactérias duas vezes com PBS e re-suspender-los em meio PAS. Diluir 10x no PAS e espalhar 2-3 ml desta diluição em uma placa de ágar PAS e deixe secar. </li></ol> Adicionar uma gota de amostra (ou de um pedaço de filtro) de um lado da placa e deixe fluir por cima da placa de Petri de modo a formar uma linha no centro do prato. 2.4. Crescimento de amebas e subcultura amebas <ol><li> Observe a placa de Petri diária. Se uma frente de migração amebas é detectado, cortar um pequeno pedaço de agar na frente de migração e inocular um novo prato NNA Petri cobertas com uma camada de E. coli. </li><li> Repetir o reinoculação várias vezes, dependendo da pureza da amostra, a fim de ter uma cultura pura de uma dada estirpe amebas. </li></ol> 2.5. Amebas e bactérias caracterização <ol><li> Raspe as células e ressuspender-los em PAS. </li><li> Extrair DNA e determinar a identidade de amebas e / ou endosimbiontes bacterianas por PCR e sequenciação (amplificação de rRNA 16S por bactérias, resp. RRNA 18S por amebas e sequenciação, por exemplo). </li> &lt;li&gt; Use essas células raspadas no PAS para inocular amebas fresco e realizar uma co-cultura amebas para detectar bactérias possivelmente presentes na amostra. </li></ol>

<ol>
	<li>Fraser, D. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Legionnaires'+disease:+description+of+an+epidemic+of+pneumonia.">Legionnaires' disease: description of an epidemic of pneumonia.</a> New Engl. J. Med. 297, 1189-1197 (1977).</li><li>McDade, J. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Legionnaires'+disease:+isolation+of+a+bacterium+and+demonstration+of+its+role+in+other+respiratory+disease.">Legionnaires' disease: isolation of a bacterium and demonstration of its role in other respiratory disease.</a> New Engl. J. Med. 297, 1197-1203 (1977).</li><li>Rowbotham, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preliminary+report+on+the+pathogenicity+of+Legionella+pneumophila+for+freshwater+and+soil+amoebae.">Preliminary report on the pathogenicity of Legionella pneumophila for freshwater and soil amoebae.</a> J. Clin. Pathol. 33, 1179-1183 (1980).</li><li>Rodriguez-Zaragoza, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ecology+of+free-living+amoebae.">Ecology of free-living amoebae.</a> Crit. Rev. Microbiol. 20, 225-241 (1994).</li><li>Booton, G. C., Visvesvara, G. S., Byers, T. J., Kelly, D. J., Fuerst, P. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+and+distribution+of+Acanthamoeba+species+genotypes+associated+with+nonkeratitis+infections.">Identification and distribution of Acanthamoeba species genotypes associated with nonkeratitis infections.</a> J Clin. Microbiol. 43, 1689-1693 (2005).</li><li>Brussow, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacteria+between+protists+and+phages:+from+antipredation+strategies+to+the+evolution+of+pathogenicity.">Bacteria between protists and phages: from antipredation strategies to the evolution of pathogenicity.</a> Molecular microbiology. 65, 583-589 (2007).</li><li>Greub, G., Raoult, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microorganisms+resistant+to+free-living+amoebae.">Microorganisms resistant to free-living amoebae.</a> Clin. Microbiol. Rev. 17, 413-433 (2004).</li><li>Thomas, V., McDonnell, G., Denyer, S. P., Maillard, J. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Free-living+amoebae+and+their+intracellular+pathogenic+microorganisms:+risks+for+water+quality.">Free-living amoebae and their intracellular pathogenic microorganisms: risks for water quality.</a> FEMS Microbiol Rev. 34, 231-259 (2010).</li><li>Birtles, R. J., Rowbotham, T. J., Storey, C., Marrie, T. J., Raoult, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chlamydia-like+obligate+parasite+of+free-living+amoebae.">Chlamydia-like obligate parasite of free-living amoebae.</a> Lancet. 349, 925-926 (1997).</li><li>Amann, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Obligate+intracellular+bacterial+parasites+of+acanthamoebae+related+to+Chlamydia+spp.">Obligate intracellular bacterial parasites of acanthamoebae related to Chlamydia spp.</a> Appl. Environ. Microbiol. 63, 115-121 (1997).</li><li>Birtles, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Candidatus+Odyssella+thessalonicensis'+gen.+nov.,+sp.+nov.,+an+obligate+intracellular+parasite+of+Acanthamoeba+species.">Candidatus Odyssella thessalonicensis' gen. nov., sp. nov., an obligate intracellular parasite of Acanthamoeba species.</a> Int. J. Syst. Evol. Microbiol. 50, 63-72 (2000).</li><li>Thomas, V., Casson, N., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Criblamydia+sequanensis,+a+new+intracellular+Chlamydiales+isolated+from+Seine+river+water+using+amoebal+co-culture.">Criblamydia sequanensis, a new intracellular Chlamydiales isolated from Seine river water using amoebal co-culture.</a> Environ. Microbiol. 8, 2125-2135 (2006).</li><li>Pagnier, I., Raoult, D., La Scola, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+identification+of+amoeba-resisting+bacteria+from+water+in+human+environment+by+using+an+Acanthamoeba+polyphaga+co-culture+procedure.">Isolation and identification of amoeba-resisting bacteria from water in human environment by using an Acanthamoeba polyphaga co-culture procedure.</a> Environ. Microbiol. 10, 1135-1144 (2008).</li><li>Thomas, V., Loret, J. F., Jousset, M., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodiversity+of+amoebae+and+amoebae-resisting+bacteria+in+a+drinking+water+treatment+plant.">Biodiversity of amoebae and amoebae-resisting bacteria in a drinking water treatment plant.</a> Environ. Microbiol. 10, 2728-2745 (2008).</li><li>Corsaro, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+Chlamydiales+strains+isolated+from+a+water+treatment+plant.">Novel Chlamydiales strains isolated from a water treatment plant.</a> Environ. Microbiol. 11, 188-200 (2009).</li><li>Goy, G., Croxatto, A., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Waddlia+chondrophila+enters+and+multiplies+within+human+macrophages.">Waddlia chondrophila enters and multiplies within human macrophages.</a> Microbes Infect. 10, 556-562 (2008).</li><li>Kebbi-Beghdadi, C., Cisse, O., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Permissivity+of+Vero+cells,+human+pneumocytes+and+human+endometrial+cells+to+Waddlia+chondrophila.">Permissivity of Vero cells, human pneumocytes and human endometrial cells to Waddlia chondrophila.</a> Microbes Infect. 13, 566-574 (2011).</li><li>Kebbi-Beghdadi, C., Batista, C., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Permissivity+of+fish+cell+lines+to+three+Chlamydia-related+bacteria:+Waddlia+chondrophila,+Estrella+lausannensis+and+Parachlamydia+acanthamoebae.">Permissivity of fish cell lines to three Chlamydia-related bacteria: Waddlia chondrophila, Estrella lausannensis and Parachlamydia acanthamoebae.</a> FEMS Immunol. Med. Microbiol. 63, 339-345 (2011).</li><li>Fry, N. K., Rowbotham, T. J., Saunders, N. A., Embley, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+amplification+and+sequencing+of+the+16S+ribosomal+DNA+of+an+intracellular+Legionella+species+recovered+by+amoebal+enrichment+from+the+sputum+of+a+patient+with+pneumonia.">Direct amplification and sequencing of the 16S ribosomal DNA of an intracellular Legionella species recovered by amoebal enrichment from the sputum of a patient with pneumonia.</a> FEMS Microbiol. Lett. 67, 165-168 (1991).</li><li>Rowbotham, T. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+of+Legionella+pneumophila+serogroup+1+from+human+feces+with+use+of+amebic+cocultures.">Isolation of Legionella pneumophila serogroup 1 from human feces with use of amebic cocultures.</a> Clin. Infect. Dis. 26, 502-503 (1998).</li><li>Greub, G., La Scola, B., Raoult, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amoebae-resisting+bacteria+isolated+from+human+nasal+swabs+by+amoebal+coculture.">Amoebae-resisting bacteria isolated from human nasal swabs by amoebal coculture.</a> Emerging Infect. Dis. 10, 470-477 (2004).</li><li>Isenberg, H. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Clinical microbiology procedures handbook. , (1992).</li><li>Gimenez, D. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Staining+Rickettsiae+in+Yolk-Sac+Cultures.">Staining Rickettsiae in Yolk-Sac Cultures.</a> Stain Technol. 39, 135-140 (1964).</li><li>Thomas, V., Herrera-Rimann, K., Blanc, D. S., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodiversity+of+amoebae+and+amoeba-resisting+bacteria+in+a+hospital+water+network.">Biodiversity of amoebae and amoeba-resisting bacteria in a hospital water network.</a> Appl. Environ. Microbiol. 72, 2428-2438 (2006).</li><li>Miyamoto, H., et al. <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+a+new+seminested+PCR+method+for+detection+of+Legionella+species+and+its+application+to+surveillance+of+legionellae+in+hospital+cooling+tower+water.">Development of a new seminested PCR method for detection of Legionella species and its application to surveillance of legionellae in hospital cooling tower water.</a> Appl. Environ. Microbiol. 63, 2489-2494 (1997).</li><li>Lienard, J., et al. <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+a+new+chlamydiales-specific+real-time+PCR+and+its+application+to+respiratory+clinical+samples.">Development of a new chlamydiales-specific real-time PCR and its application to respiratory clinical samples.</a> J. Clin. Microbiol. 49, 2637-2642 (2011).</li><li>Wang, Y., Ogawa, M., Fukuda, K., Miyamoto, H., Taniguchi, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Isolation+and+identification+of+mycobacteria+from+soils+at+an+illegal+dumping+site+and+landfills+in+Japan.">Isolation and identification of mycobacteria from soils at an illegal dumping site and landfills in Japan.</a> Microbiol. Immunol. 50, 513-524 (2006).</li><li>Corsaro, D., Pages, G. S., Catalan, V., Loret, J. F., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodiversity+of+amoebae+and+amoeba-associated+bacteria+in+water+treatment+plants.">Biodiversity of amoebae and amoeba-associated bacteria in water treatment plants.</a> Int. J. Hygiene Environ. Health. 213, 158-166 (2010).</li><li>La Scola, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Legionella+drancourtii+sp.+nov.,+a+strictly+intracellular+amoebal+pathogen.">Legionella drancourtii sp. nov., a strictly intracellular amoebal pathogen.</a> Int. J. Syst. Evol. Microbiol. 54, 699-703 (2004).</li><li>Thomas, V., Casson, N., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+Afipia+and+Bosea+strains+isolated+from+various+water+sources+by+amoebal+co-culture.">New Afipia and Bosea strains isolated from various water sources by amoebal co-culture.</a> Syst. Appl. Microbiol. 30, 572-579 (2007).</li><li>La Scola, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amoeba-resisting+bacteria+and+ventilator-associated+pneumonia.">Amoeba-resisting bacteria and ventilator-associated pneumonia.</a> Emerging Infect. Dis. 9, 815-821 (2003).</li><li>Collingro, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recovery+of+an+environmental+Chlamydia+strain+from+activated+sludge+by+co-cultivation+with+Acanthamoeba+sp.">Recovery of an environmental Chlamydia strain from activated sludge by co-cultivation with Acanthamoeba sp.</a> Microbiology. 151, 301-309 (2005).</li><li>Lienard, J., Croxatto, A., Prod'hom, G., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estrella+lausannensis,+a+new+star+in+the+Chlamydiales+order.">Estrella lausannensis, a new star in the Chlamydiales order.</a> Microbes Infect. 13, 1232-1241 (2011).</li><li>La Scola, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+giant+virus+in+amoebae.">A giant virus in amoebae.</a> Science. 299, 2033 (2003).</li><li>Boyer, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Giant+Marseillevirus+highlights+the+role+of+amoebae+as+a+melting+pot+in+emergence+of+chimeric+microorganisms.">Giant Marseillevirus highlights the role of amoebae as a melting pot in emergence of chimeric microorganisms.</a> Proc. Natl. Acad. Sci. U.S.A. 106, 21848-21853 (2009).</li><li>Thomas, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lausannevirus,+a+giant+amoebal+virus+encoding+histone+doublets.">Lausannevirus, a giant amoebal virus encoding histone doublets.</a> Environ. Microbiol. 13, 1454-1466 (2011).</li><li>Raoult, D., Renesto, P., Brouqui, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+infection+of+a+technician+by+mimivirus.">Laboratory infection of a technician by mimivirus.</a> Ann. Internal Med. 144, 702-703 (2006).</li><li>Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Parachlamydia+acanthamoebae,+an+emerging+agent+of+pneumonia.">Parachlamydia acanthamoebae, an emerging agent of pneumonia.</a> Clin. Microbiol. Infect. 15, 18-28 (2009).</li><li>Lamoth, F., Greub, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amoebal+pathogens+as+emerging+causal+agents+of+pneumonia.">Amoebal pathogens as emerging causal agents of pneumonia.</a> FEMS Microbiol. Rev. 34, 260-280 (2010).</li><li>Lienard, J. G., Ashbolt, K., Sen, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ch.+6.">Ch. 6.</a> Environmental microbiology, current technology and water applications. , 143-162 (2011).</li><li>Boughalmi, M., et al. <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+isolation+of+giant+viruses+of+the+Mimiviridae+and+Marseilleviridae+families+in+the+Tunisian+environment.">High-throughput isolation of giant viruses of the Mimiviridae and Marseilleviridae families in the Tunisian environment.</a> Environ. Microbiol. , (2012).</li><li>Ovrutsky, A. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cooccurrence+of+Free-Living+Amoebae+and+Nontuberculous+Mycobacteria+in+Hospital+Water+Networks,+and+Preferential+Growth+of+Mycobacterium+avium+in+Acanthamoeba+lenticulata.">Cooccurrence of Free-Living Amoebae and Nontuberculous Mycobacteria in Hospital Water Networks, and Preferential Growth of Mycobacterium avium in Acanthamoeba lenticulata.</a> Appl. Environ. Microbiol. 79, 3185-3192 (2013).</li></ol>

Os autores declaram que não têm interesses financeiros concorrentes.

Co-cultura de amebas e enriquecimento amebas são métodos eficientes que permitiram o isolamento de muitas novas espécies de bactérias e amebas. Os resultados obtidos com estes métodos confirmam a presença ubíqua de ambos amebas e bactérias resistentes ameba do ambiente, e mais interessante em redes de água feitos pelo homem, que são considerados para ser controlada por meio de tratamentos químicos tais como a cloração e ozonização. Co-cultura de amebas e enriquecimento amebas são ferramentas essenciais p...

Antes do advento de diagnóstico molecular, os microrganismos presentes em nichos ambientais ou em amostras clínicas foram frequentemente detectado cultivando-os em diferentes meios selectivos, principalmente em agar em pratos de Petri. O fenótipo das colónias de bactérias e a sua actividade metabólica depois deixada classificação bacteriana ao nível da espécie. Caldo também pode ser usado para aumentar a sensibilidade de detecção. No entanto, ambas as técnicas não permitem a recuperação de bactérias que crescem lentamente ou não em todos nestes meios. Esta é a razão pela qual abordagens moleculares são tão amplamente utilizados hoje em dia. No entanto, a detecção de ADN não fornece nenhuma pista sobre a viabilidade das bactérias. Além disso, ao contrário da cultura, as abordagens moleculares não resultar numa estirpe que pode ser ainda caracterizada. Estudar patógenos que crescem pouco em meios sólidos ou que as células precisam para crescer é complicado. A maioria destes &quot;difícil crescer&quot; bactérias são intr exigenteacelular bactérias, muitas vezes descoberto e caracterizado seguinte grandes surtos como era o caso de Legionella pneumophila. Esta bactéria foi marcado após um surto que ocorreu durante uma convenção da Legião Americana. Tal como muitos como 182 pessoas foram infectadas e 29 morreram devido a uma pneumonia grave 1,2. Mais tarde, foi demonstrado que as amebas foram os anfitriões naturais desta bactéria e que a sua presença nas redes de hotel do sistema de ar-condicionado e água esteve na origem do surto da doença a chamada do Legionário 3. Amebas estão presentes em todo o mundo e foram isolados do solo, do ar, da água e da mucosa nasal de voluntários humanos (revisada em 4). Essas amebas &quot;vida livre&quot; são geralmente dividindo de forma autônoma no ambiente, mas ocasionalmente pode invadir hospedeiros permissivos 5. Alimentação Amebas em vários microorganismos através de fagocitose e digestão lisossômico subseqüente por hydrolases 6. Muitas bactérias intracelulares facultativos ou obrigatórios são capazes de resistir a digestão e, assim, infectar e se dividir em amebas como por exemplo bactérias ou micobactérias relacionadas com Chlamydia Legionella, (revisto em 7 e 8). Amebas de vida livre provavelmente representam um importante reservatório potencial de bactérias intracelulares que ainda não foram descobertos. Isso levou nosso grupo a implementar em Lausanne duas técnicas principais, chamados de co-cultura amebas e enriquecimento amebas, o que permitiu diferentes grupos para isolar vários novos microrganismos intracelulares obrigatórios a partir de várias amostras ambientais 9-15. Desde amebas são fagócitos profissionais que pastam em bactérias, uma bactéria capaz de resistir a fagocitose e crescer dentro destes protistas também pode colonizar fagócitos humanos e ser patogênico para seres humanos. Este efeito foi parcialmente demonstrada para algumas bactérias relacionadas com a Chlamydia, como Waddlia chondrophila. W. chondrophila pode crescer não apenas em amebas, mas também em vários tipos de células, tais como células de mamíferos epiteliais, macrófagos, e linhas celulares de peixe 16-18. A co-cultura amebas também parece relevante para a detecção de bactérias intracelulares em amostras clínicas 19,20, incluindo fezes que são fortemente contaminados com diferentes espécies de bactérias 21. Aqui nós descrevemos as principais etapas de co-cultura amebas e enriquecimento amebas, incluindo (a) tratamento de amostras ambientais e clínicas, (b) o crescimento de amebas em mídia axênicas e em um gramado bacteriano de Escherichia coli e (c) a seleção e caracterização de bactérias intracelulares.

<table border="1">
	<tbody>
		<tr>
			<td>Name of Reagent/ Equipment</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments/Description</td>
		</tr>
		<tr>
			<td>Glucose monohydrate</td>
			<td>Merck, Darmstadt, Germany</td>
			<td>108342</td>
			<td></td>
		</tr>
		<tr>
			<td>0.22 &#956;m pore size membrane</td>
			<td>Merck Millipore, Darmstadt, Germany</td>
			<td>SCVPU11RE</td>
			<td></td>
		</tr>
		<tr>
			<td>proteose peptone</td>
			<td>Becton-Dickinson, Franklin Lakes, NJ</td>
			<td>211693</td>
			<td></td>
		</tr>
		<tr>
			<td>yeast extract</td>
			<td>Becton-Dickinson, Franklin Lakes, NJ</td>
			<td>212750</td>
			<td></td>
		</tr>
		<tr>
			<td>Cell culture flasks</td>
			<td>Becton-Dickinson, Franklin Lakes, NJ</td>
			<td>353135</td>
			<td></td>
		</tr>
		<tr>
			<td>Kova slide</td>
			<td>Hycor, Indianapolis, IN</td>
			<td>87144</td>
			<td></td>
		</tr>
		<tr>
			<td>cell culture microplates</td>
			<td>Corning Inc, Corning, NY</td>
			<td>3524</td>
			<td></td>
		</tr>
		<tr>
			<td>Diff-Quik staining kit</td>
			<td>Siemens Healthcare diagn., Munich, Germany</td>
			<td>130832</td>
			<td></td>
		</tr>
		<tr>
			<td>Ziehl fuchsin</td>
			<td>Fluka, St-Louis, MI</td>
			<td>21820</td>
			<td></td>
		</tr>
		<tr>
			<td>basic fuchsin</td>
			<td>Sigma, St-Louis, MI</td>
			<td>857843</td>
			<td></td>
		</tr>
		<tr>
			<td>Phenol</td>
			<td>Sigma, St-Louis, MI</td>
			<td>P1037</td>
			<td>Corrosive and mutagenic</td>
		</tr>
		<tr>
			<td>malachite green oxalate</td>
			<td>Fluka, St-Louis, MI</td>
			<td>63160</td>
			<td></td>
		</tr>
		<tr>
			<td>Paraformaldehyde 16% solution</td>
			<td>Electron Microscopy Sciences, Hatfield, PA</td>
			<td>15710</td>
			<td></td>
		</tr>
		<tr>
			<td>Saponin</td>
			<td>Sigma, St-Louis, MI</td>
			<td>84510</td>
			<td></td>
		</tr>
	</tbody>
</table>

discovery of new intracellular pathogens by amoebal coculture and amoebal enrichment approaches

Patógenos intracelulares como legionella, micobactérias e organismos Chlamydia-como são difíceis de isolar, porque eles geralmente crescem pouco ou nada em meios seletivos que são normalmente utilizados para cultivar bactérias. Por esta razão, muitos destes patógenos foram descobertos apenas recentemente, ou na sequência de surtos importantes. Estes patógenos são frequentemente associados com amebas, que servem como-célula hospedeira e permitir a sobrevivência eo crescimento das bactérias. Pretendemos aqui para dar uma demonstração de duas técnicas que permitem o isolamento e caracterização de patógenos intracelulares presentes em amostras clínicas e ambientais: a co-cultura amebas eo enriquecimento amebas. Cocultura amebas permite a recuperação de bactérias intracelulares, inoculando a amostra investigada para um relvado amebas que podem ser infectadas e lisadas por bactérias intracelulares presentes na amostra. Enriquecimento amebas permite a recuperação de amebas presente numa amostra clínica ou ambiental. ThÉ possível levar à descoberta de novas espécies de amebas, mas também de novas bactérias intracelulares crescem especificamente nestas amebas. Juntas, essas duas técnicas ajudam a descobrir novas bactérias intracelulares capazes de crescer em amebas. Devido à sua capacidade para infectar as amebas e resistir a fagocitose, estas bactérias intracelulares também pode escapar a fagocitose pelos macrófagos e, assim, ser patogénico para eucariotas superiores.

Utilizando co-cultura amebas e enriquecimento amebas, toda uma gama de bactérias do ambiente e / ou patogénicos foram descobertos (Tabela 1). Co-cultura de amebas foi utilizada pelo nosso grupo e outros, para analisar amostras ambientais, estações de tratamento de água e sistemas de distribuição de água. Uma ampla gama de microorganismos pode ser isolado, com esta técnica. As bactérias mais comuns isoladas por co-cultura amebas são membros do gênero Mycobacte...

Watch this Scientific Journal Video about Discovery of New Intracellular Pathogens by Amoebal Coculture and Amoebal Enrichment Approaches at JoVE.com

Discovery of New Intracellular Pathogens by Amoebal Coculture and Amoebal Enrichment Approaches

Cocultura amebas é um sistema de cultura de células usando as amebas aderente para crescer selectivamente patogénios intracelulares capazes de resistir as células fagocíticas, tais como amebas e macrófagos. Representa, portanto, uma ferramenta-chave para descobrir novos agentes infecciosos. Enriquecimento amebas permite a descoberta de novas espécies de amebas e das suas bactérias intracelulares específicos.

Descoberta de Novos intracelulares Patógenos por amebas Coculture e Abordagens de amebas de enriquecimento

Intracellular pathogens such as legionella, mycobacteria and Chlamydia-like organisms are difficult to isolate because they often grow poorly or not at ...

discovery-new-intracellular-pathogens-amoebal-coculture-amoebal

Research

JoVE Journal

Immunology and Infection

14.4K visualizações.  University Hospital Center and University of Lausanne.  Cocultura amebas é um sistema de cultura de células usando as amebas aderente para crescer selectivamente patogénios intracelulares capazes de resistir as células fagocíticas, tais como amebas e macrófagos. Representa, portanto, uma ferramenta-chave para descobrir novos agentes infecciosos. Enriquecimento amebas permite a descoberta de novas espécies de amebas e das suas bactérias intracelulares específicos. 

Vídeo: Discovery of New Intracellular Pathogens by Amoebal Coculture and Amoebal Enrichment Approaches

Infection of Zebrafish Embryos with Intracellular Bacterial Pathogens

Zebrafish (Danio rerio) embryos are increasingly used as a model for studying the function of the vertebrate innate immune system in host-pathogen interactions 1. The major cell types of the innate immune system, macrophages and neutrophils, develop during the first days of embryogenesis prior to the maturation of lymphocytes that are required for adaptive immune responses. The ease of obtaining large numbers of embryos, their accessibility due to external development, the optical transparency of embryonic and larval stages, a wide range of genetic tools, extensive mutant resources and collections of transgenic reporter lines, all add to the versatility of the zebrafish model. Salmonella enterica serovar Typhimurium (S. typhimurium) and Mycobacterium marinum can reside intracellularly in macrophages and are frequently used to study host-pathogen interactions in zebrafish embryos. The infection processes of these two bacterial pathogens are interesting to compare because S. typhimurium infection is acute and lethal within one day, whereas M. marinum infection is chronic and can be imaged up to the larval stage 2, 3. The site of micro-injection of bacteria into the embryo (Figure 1) determines whether the infection will rapidly become systemic or will initially remain localized. A rapid systemic infection can be established by micro-injecting bacteria directly into the blood circulation via the caudal vein at the posterior blood island or via the Duct of Cuvier, a wide circulation channel on the yolk sac connecting the heart to the trunk vasculature. At 1 dpf, when embryos at this stage have phagocytically active macrophages but neutrophils have not yet matured, injecting into the blood island is preferred. For injections at 2-3 dpf, when embryos also have developed functional (myeloperoxidase-producing) neutrophils, the Duct of Cuvier is preferred as the injection site. To study directed migration of myeloid cells towards local infections, bacteria can be injected into the tail muscle, otic vesicle, or hindbrain ventricle 4-6. In addition, the notochord, a structure that appears to be normally inaccessible to myeloid cells, is highly susceptible to local infection 7. A useful alternative for high-throughput applications is the injection of bacteria into the yolk of embryos within the first hours after fertilization 8. Combining fluorescent bacteria and transgenic zebrafish lines with fluorescent macrophages or neutrophils creates ideal circumstances for multi-color imaging of host-pathogen interactions. This video article will describe detailed protocols for intravenous and local infection of zebrafish embryos with S. typhimurium or M. marinum bacteria and for subsequent fluorescence imaging of the interaction with cells of the innate immune system.

Transparent zebrafish embryos have proved useful model hosts to visualize and functionally study interactions between innate immune cells and intracellular bacterial pathogens, such as Salmonella typhimurium and Mycobacterium marinum. Micro-injection of bacteria and multi-color fluorescence imaging are essential techniques involved in the application of zebrafish embryo infection models.

A infecção de embriões de zebrafish com patógenos bacterianos intracelulares

Zebrafish (Danio rerio) embryos are increasingly used as a model for studying the function of the vertebrate innate immune system in host-pathogen ...

Imunologia e Infecção

Single Cell Measurements of Vacuolar Rupture Caused by Intracellular Pathogens

Shigella flexneri are pathogenic bacteria that invade host cells entering into an endocytic vacuole. Subsequently, the rupture of this membrane-enclosed compartment allows bacteria to move within the cytosol, proliferate and further invade neighboring cells. Mycobacterium tuberculosis is phagocytosed by immune cells, and has recently been shown to rupture phagosomal membrane in macrophages. We developed a robust assay for tracking phagosomal membrane disruption after host cell entry of Shigella flexneri or Mycobacterium tuberculosis. The approach makes use of CCF4, a FRET reporter sensitive to &beta;-lactamase that equilibrates in the cytosol of host cells. Upon invasion of host cells by bacterial pathogens, the probe remains intact as long as the bacteria reside in membrane-enclosed compartments. After disruption of the vacuole, &beta;-lactamase activity on the surface of the intracellular pathogen cleaves CCF4 instantly leading to a loss of FRET signal and switching its emission spectrum. This robust ratiometric assay yields accurate information about the timing of vacuolar rupture induced by the invading bacteria, and it can be coupled to automated microscopy and image processing by specialized algorithms for the detection of the emission signals of the FRET donor and acceptor. Further, it allows investigating the dynamics of vacuolar disruption elicited by intracellular bacteria in real time in single cells. Finally, it is perfectly suited for high-throughput analysis with a spatio-temporal resolution exceeding previous methods. Here, we provide the experimental details of exemplary protocols for the CCF4 vacuolar rupture assay on HeLa cells and THP-1 macrophages for time-lapse experiments or end points experiments using Shigella flexneri as well as multiple mycobacterial strains such as Mycobacterium marinum, Mycobacterium bovis, and Mycobacterium tuberculosis.

We describe a method for tracking the endomembrane rupture elicited by the intracellular bacteria Shigella flexneri and Mycobacterium tuberculosis upon host cell invasion. Our assay makes use of CCF4, a host cytoplasmic FRET probe in live or fixed cells. This reporter is degraded by an enzyme activity present on the bacterial surface.

Medidas de ruptura vacuolar única célula causadas por patógenos intracelulares

Shigella flexneri are pathogenic bacteria that invade host cells entering into an endocytic vacuole. Subsequently, the rupture of this membrane-enclosed ...

Monitoring Changes in Membrane Polarity, Membrane Integrity, and Intracellular Ion Concentrations in Streptococcus pneumoniae Using Fluorescent Dyes

Membrane depolarization and ion fluxes are events that have been studied extensively in biological systems due to their ability to profoundly impact cellular functions, including energetics and signal transductions. While both fluorescent and electrophysiological methods, including electrode usage and patch-clamping, have been well developed for measuring these events in eukaryotic cells, methodology for measuring similar events in microorganisms have proven more challenging to develop given their small size in combination with the more complex outer surface of bacteria shielding the membrane. During our studies of death-initiation in Streptococcus pneumoniae (pneumococcus), we wanted to elucidate the role of membrane events, including changes in polarity, integrity, and intracellular ion concentrations. Searching the literature, we found that very few studies exist. Other investigators had monitored radioisotope uptake or equilibrium to measure ion fluxes and membrane potential and a limited number of studies, mostly in Gram-negative organisms, had seen some success using carbocyanine or oxonol fluorescent dyes to measure membrane potential, or loading bacteria with cell-permeant acetoxymethyl (AM) ester versions of ion-sensitive fluorescent indicator dyes. We therefore established and optimized protocols for measuring membrane potential, rupture, and ion-transport in the Gram-positive organism S. pneumoniae. We developed protocols using the bis-oxonol dye DiBAC4(3) and the cell-impermeant dye propidium iodide to measure membrane depolarization and rupture, respectively, as well as methods to optimally load the pneumococci with the AM esters of the ratiometric dyes Fura-2, PBFI, and BCECF to detect changes in intracellular concentrations of Ca2+, K+, and H+, respectively, using a fluorescence-detection plate reader. These protocols are the first of their kind for the pneumococcus and the majority of these dyes have not been used in any other bacterial species. Though our protocols have been optimized for S. pneumoniae, we believe these approaches should form an excellent starting-point for similar studies in other bacterial species.

Monitoring Changes in Membrane Polarity, Membrane Integrity, and Intracellular Ion Concentrations in Streptococcus pneumoniae Using Fluorescent Dyes

Unlike that seen for eukaryotes, there is a paucity of studies that detail membrane depolarization and ion concentration changes in bacteria, primarily as their small size makes conventional methods of measurement difficult. Here, we detail protocols for monitoring such events in the significant Gram-positive pathogen Streptococcus pneumoniae utilizing fluorescence techniques.

Acompanhamento da evolução das Membrane Polaridade, integridade de membrana e intracelulares Ion concentrações no<em&gt; Streptococcus pneumoniae</em&gt; Usando corantes fluorescentes

Membrane depolarization and ion fluxes are events that have been studied extensively in biological systems due to their ability to profoundly impact ...

Application of Fluorescent Nanoparticles to Study Remodeling of the Endo-lysosomal System by Intracellular Bacteria

Fluorescent nanoparticles (NPs) with desirable chemical, optical and mechanical properties are promising tools to label intracellular organelles. Here, we introduce a method using gold-BSA-rhodamine NPs to label the endo-lysosomal system of eukaryotic cells and monitor manipulations of host cellular pathways by the intracellular pathogen Salmonella enterica. The NPs were readily internalized by HeLa cells and localized in late endosomes/lysosomes. Salmonella infection induced rearrangement of the vesicles and accumulation of NPs in Salmonella-induced membrane structures. We deployed the Imaris software package for quantitative analyses of confocal microscopy images. The number of objects and their size distribution in non-infected cells were distinct from the ones in Salmonella-infected cells, indicating extremely remodeling of the endo-lysosomal system by WT Salmonella.

This article describes methods for the synthesis and fluorescent labeling of nanoparticles (NPs). The NPs were applied in pulse-chase experiments to label the endo-lysosomal system of eukaryotic cells. Manipulation of the endo-lysosomal system by activities of the intracellular pathogen Salmonella enterica were followed by live cell imaging and quantified.

Aplicação de nanopartículas fluorescentes para estudar Reformas do Sistema Endo-lysosomal por bactérias intracelulares

Fluorescent nanoparticles (NPs) with desirable chemical, optical and mechanical properties are promising tools to label intracellular organelles. Here, we ...

Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans

The basidiomycete Cryptococcus neoformans, an invasive opportunistic pathogen of the central nervous system, is the most frequent cause of fungal meningitis worldwide resulting in more than 625,000 deaths per year worldwide.&#160;Although electroporation has been developed for the transformation of plasmids in Cryptococcus, only&#160;biolistic&#160;delivery provides&#160;an effective means to transform&#160;linear&#160;DNA&#160;that can be integrated into the genome by homologous recombination.&#160;
Acetate has been shown to be a major fermentation product during cryptococcal infection, but the significance of this is not yet known.&#160;A bacterial pathway composed of the enzymes xylulose-5-phosphate/fructose-6-phosphate phosphoketolase (Xfp) and acetate kinase (Ack) is one of three potential pathways for acetate production in C. neoformans. Here, we demonstrate the biolistic transformation of a construct, which has the gene encoding Ack fused to the fluorescent tag mCherry, into&#160;C. neoformans. We then confirm integration of the ACK-mCherry fusion into the&#160;ACK&#160;locus.

Biolistic Transformation of a Fluorescent Tagged Gene into the Opportunistic Fungal Pathogen Cryptococcus neoformans

Biolistic transformation is a method used to generate stable integration of DNA into the genome of the opportunistic pathogen Cryptococcus neoformans through homologous recombination. We will demonstrate biolistic transformation of a construct, which has the gene encoding acetate kinase fused to the fluorescent tag mCherry into&#160;C. neoformans.

Transformação Biolistic de uma fluorescente Tagged Gene para o oportunista fúngica Pathogen<em&gt; Cryptococcus neoformans</em

The basidiomycete Cryptococcus neoformans, an invasive opportunistic pathogen of the central nervous system, is the most frequent cause of fungal ...

Identification of Rare Bacterial Pathogens by 16S rRNA Gene Sequencing and MALDI-TOF MS

There are a number of rare and, therefore, insufficiently described bacterial pathogens which are reported to cause severe infections especially in immunocompromised patients. In most cases only few data, mostly published as case reports, are available which investigate the role of such pathogens as an infectious agent. Therefore, in order to clarify the pathogenic character of such microorganisms, it is necessary to conduct epidemiologic studies which include large numbers of these bacteria. The methods used in such a surveillance study have to meet the following criteria: the identification of the strains has to be accurate according to the valid nomenclature, they should be easy to handle (robustness), economical in routine diagnostics and they have to generate comparable results among different laboratories. Generally, there are three strategies for identifying bacterial strains in a routine setting: 1) phenotypic identification characterizing the biochemical and metabolic properties of the bacteria, 2) molecular techniques such as 16S rRNA gene sequencing and 3) mass spectrometry as a novel proteome based approach. Since mass spectrometry and molecular approaches are the most promising tools for identifying a large variety of bacterial species, these two methods are described. Advances, limitations and potential problems when using these techniques are discussed.

Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) and molecular techniques (16S rRNA gene sequencing) permit the identification of rare bacterial pathogens in routine diagnostics. The goal of this protocol lies in the combination of both techniques which leads to more accurate and reliable data.

Identificação de patógenos bacterianos raras, seqüência do gene 16rRNA e MALDI-TOF MS

There are a number of rare and, therefore, insufficiently described bacterial pathogens which are reported to cause severe infections especially in ...

High-throughput Detection of Respiratory Pathogens in Animal Specimens by Nanoscale PCR

Nanoliter scale real-time PCR uses spatial multiplexing to allow multiple assays to be run in parallel on a single plate without the typical drawbacks of combining reactions together. We designed and evaluated a panel based on this principle to rapidly identify the presence of common disease agents in dogs and horses with acute respiratory illness. This manuscript describes a nanoscale diagnostic PCR workflow for sample preparation, amplification, and analysis of target pathogen sequences, focusing on procedures that are different from microliter scale reactions. In the respiratory panel presented, 18 assays were each set up in triplicate, accommodating up to 48 samples per plate. A universal extraction and pre-amplification workflow was optimized for high-throughput sample preparation to accommodate multiple matrices and DNA and RNA based pathogens. Representative data are presented for one RNA target (influenza A matrix) and one DNA target (equine herpesvirus 1). The ability to quickly and accurately test for a comprehensive, syndrome-based group of pathogens is a valuable tool for improving efficiency and ergonomics of diagnostic testing and for acute respiratory disease diagnosis and management.

High-throughput testing of DNA and RNA based pathogens by nanoscale PCR is described using a syndromic canine and equine respiratory PCR panel.

Detecção de alto rendimento de patógenos respiratórios em espécimes animais por Nanoscale PCR

Nanoliter scale real-time PCR uses spatial multiplexing to allow multiple assays to be run in parallel on a single plate without the typical drawbacks of ...

Visualizing Intracellular SNARE Trafficking by Fluorescence Lifetime Imaging Microscopy

Soluble N-ethylmaleimide sensitive fusion protein (NSF) attachment protein receptor (SNARE) proteins are key for membrane trafficking, as they catalyze membrane fusion within eukaryotic cells. The SNARE protein family consists of about 36 different members. Specific intracellular transport routes are catalyzed by specific sets of 3 or 4 SNARE proteins that thereby contribute to the specificity and fidelity of membrane trafficking. However, studying the precise function of SNARE proteins is technically challenging, because SNAREs are highly abundant and functionally redundant, with most SNAREs having multiple and overlapping functions. In this protocol, a new method for the visualization of SNARE complex formation in live cells is described. This method is based on expressing SNARE proteins C-terminally fused to fluorescent proteins and measuring their interaction by F&#246;rster resonance energy transfer (FRET) employing fluorescence lifetime imaging microscopy (FLIM). By fitting the fluorescence lifetime histograms with a multicomponent decay model, FRET-FLIM allows (semi-)quantitative estimation of the fraction of the SNARE complex formation at different vesicles. This protocol has been successfully applied to visualize SNARE complex formation at the plasma membrane and at endosomal compartments in mammalian cell lines and primary immune cells, and can be readily extended to study SNARE functions at other organelles in animal, plant, and fungal cells.

This protocol describes a new method allowing for the quantitative visualization of complex formation of SNARE proteins, based on F&#246;rster resonance energy transfer, and fluorescence lifetime imaging microscopy.

Visualizando intracelular SNARE tráfico pela vida de fluorescência, microscopia de imagem

Soluble N-ethylmaleimide sensitive fusion protein (NSF) attachment protein receptor (SNARE) proteins are key for membrane trafficking, as they catalyze ...

Zika Virus Specific Diagnostic Epitope Discovery

High-density peptide microarrays allow screening of more than six thousand peptides on a single standard microscopy slide. This method can be applied for drug discovery, therapeutic target identification, and developing of diagnostics. Here, we present a protocol to discover specific Zika virus (ZIKV) diagnostic peptides using a high-density peptide microarray. A human serum sample validated for ZIKV infection was incubated with a high-density peptide microarray containing the entire ZIKV protein translated into 3,423 unique 15 linear amino acid (aa) residues with a 14-aa residue overlap printed in duplicate. Staining with different secondary antibodies within the same array, we detected peptides that bind to Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibodies present in serum. These peptides were selected for further validation experiments. In this protocol, we describe the strategy followed to design, process, and analyze a high-density peptide microarray.

In this protocol, we describe a technique to discover Zika virus specific diagnostic peptides using a high-density peptide microarray. This protocol can readly be adapted for other emerging infectious diseases.

Zika vírus específico diagnóstico Epitope Discovery

High-density peptide microarrays allow screening of more than six thousand peptides on a single standard microscopy slide. This method can be applied for ...

Human Colonoid Monolayers to Study Interactions Between Pathogens, Commensals, and Host Intestinal Epithelium

Human 3-dimensional (3D) enteroid or colonoid cultures derived from crypt base stem cells are currently the most advanced ex vivo model of the intestinal epithelium. Due to their closed structures and significant supporting extracellular matrix, 3D cultures are not ideal for host-pathogen studies. Enteroids or colonoids can be grown as epithelial monolayers on permeable tissue culture membranes to allow manipulation of both luminal and basolateral cell surfaces and accompanying fluids. This enhanced luminal surface accessibility facilitates modeling bacterial-host epithelial interactions such as the mucus-degrading ability of enterohemorrhagic E. coli (EHEC) on colonic epithelium. A method for 3D culture fragmentation, monolayer seeding, and transepithelial electrical resistance (TER) measurements to monitor the progress towards confluency and differentiation are described. Colonoid monolayer differentiation yields secreted mucus that can be studied by the immunofluorescence or immunoblotting techniques. More generally, enteroid or colonoid monolayers enable a physiologically-relevant platform to evaluate specific cell populations that may be targeted by pathogenic or commensal microbiota.

Here, we present a protocol to culture human enteroid or colonoid monolayers that have intact barrier function to study host epithelial-microbiota interactions at the cellular and biochemical level.

Colonoid humana monocamadas para estudar interações entre epitélio Intestinal do hospedeiro, comensais e patógenos

Human 3-dimensional (3D) enteroid or colonoid cultures derived from crypt base stem cells are currently the most advanced ex vivo model of the intestinal ...