Die Autoren möchten die technische Unterstützung von Michelle Banes sowie Dr. Petrie-Hanson, Dr. Aale und Timothy Brown für ihre Unterstützung der Entwicklung und Durchführung der Immunhistochemie zu erkennen. Dieses Projekt wurde von USDA CRIS Projekt # MISV-0801310 und der Mississippi State University College of Veterinary Medicine finanziert.

<html> 1. Bakterielle Herausforderung <ol><li> Bakterien wachsen über Nacht bei 30 ° C in Schüttel Brain Heart Infusion Broth. </li><li> Stoppen Wasserzirkulation in den Fischbecken und Brühe in einer Konzentration von 1 in 100 (10 ml pro Liter, zum Beispiel). </li><li> Nach einer einstündigen Inkubation, starten Wasserzirkulation in den Tanks zu spülen, die restlichen Bakterien. </li></ol> 2. Stichprobenverfahren <ol><li> Abtastzeiten und Organe hängt von der Zielsetzung der Studie, aber in unserer Studie haben wir die folgenden Messstellen: 1, 6, 16, 24, 36, 48, 60, 72, 96, 110, 125 und 175 Stunden nach der Infektion . </li><li> Zu jedem Zeitpunkt Punkten euthanize sechs Fische durch Eintauchen in Wasser mit MS222 und probieren Sie die folgenden Organe (Auswahl der Organe abgetastet wurde, was ist der Ablauf der Infektion bekannt ist): Kiemen, hinteren Muskeln entlang der Seitenlinie, Darm, Milz, Leber, Magen, Herz, Kopf Niere und Kofferraum Niere. </li><li> Nach Probenahme, sofort laden die Organe in histologischen Kassetten und tauche sie für zwei Stunden in 1% Formalin. </li><li> Nach zwei Stunden Fixierung, übertragen Sie die Kassetten aus Formalin zu 50% Ethanol, wo sie bis Einbettung bleiben. </li><li> Paraffin eingebettet Organe über Nacht mit einem Gewebe-Tek VIP 3000 Gewebe-Prozessor (Sakura Tek, Torrance, Kalifornien) und Abschnitt bei 5 um mit einem Leica RM2255 microtone (Leica Microsystems, Bannockburn, Illinois). </li></ol> 3. Entwachsen Abschnitte <ol><li> Tauchen Sie die Abschnitte in einem Färbetrog mit klar-rite für ca. 5 Minuten gefüllt, um für das gesamte Wachs zu lösen lassen. Heben Sie die Rack-und abtropfen überschüssige Wachs Lösungsmittel. </li><li> Tauchen Sie die Teile in einen zweiten Behälter aus klarem Ritus für 5 Minuten. Nach ein paar verwendet, ersetzen Sie das Lösungsmittel in den ersten Behälter und wechseln zwischen dem ersten und dem zweiten Behälter. </li><li> Tauchen Sie die Abschnitte in 100% igem Alkohol zu entfernen das Wachs Lösungsmittel. </li><li> Tauchen Sie die Abschnitte in einem zweiten Trog von 100% igem Alkohol. </li><li> Tauchen Sie die Teile in einem Trog von 70% Alkohol. </li><li> Tauchen Sie die Abschnitte in fließendem Leitungswasser, um alle Spuren von Alkohol zu entfernen. </li></ol> 4. Buffer Vorbereitung <ol><li> Bereiten Sie phosphatgepufferte Kochsalzlösung durch Auflösen von 8,0 g NaCl, 0,2 g KCl, 1,15 g Na 2 HPO 4 und 0,2 g KH 2 PO 4 in 1 Liter destilliertem Wasser und pH-Wert auf 7,4. </li><li> Verdünnen PBS auf 0.9X durch Zugabe von 900 ml PBS auf 100 ml destilliertem Wasser. </li><li> Bereiten Blockierserum durch Zugabe von 2 ml Maus-Serum, 200 ul Triton-X 100 und 500 ul BSA in 50 ml 0.9X PBS. </li><li> Bereiten 50 mM Bicarbonat-gepufferte Kochsalzlösung durch Auflösen von 2,1 g NaHCO 3 und 4 g NaCl in 500 ml destilliertem H 2 O und titriert bis pH 8,2 hergestellt. </li></ol> 5. Immunhistochemie <ol><li> Rehydrieren Abschnitte durch Eintauchen in 0.9X PBS. </li><li> Inkubieren Sie die Objektträger 30 Minuten in Blockierserum. </li><li> Inkubieren Abschnitte in ED9 (verwässert 1 in 100 in der Blockierserum) für zwei Stunden in einem undurchsichtigen feuchten Kammer bei Raumtemperatur. </li><li> Spülen Sie den Abschnitten 4 mal in PBS für jeweils 10 Minuten. </li><li> Inkubieren Abschnitte für 2 Stunden in 50 ul der Sekundärantikörper (Ziege anti-Maus FITC-markierten Antikörper, verdünnt 500 Mal in Blockierserum) in einem undurchsichtigen feuchten Kammer bei Raumtemperatur. </li><li> Spülen Sie den Abschnitten 3 mal in Bicarbonate Kochsalzlösung. </li><li> Spülen Abschnitten wird kurz in VE-Wasser. </li></ol> 6. Montage <ol><li> Lassen Sie die Folien in der Dunkelheit für ein paar Minuten trocknen lassen. </li><li> Montage erfolgt mit Hilfe permafluor. </li><li> Lassen Sie die Montage mittel-bis trocken, bevorzugt über Nacht in einem dunklen kühlen Umgebung. </li></ol> 7. Mikroskop <ol><li> Histologische Schnitte sind bereit, unter einem Fluoreszenzmikroskop beobachten. In unserem Experiment haben wir ein Olympus BX51 Mikroskop mit einer Dreifach-(FITC; MCA Texas-Rot) ausgestattet Filter. Der Picture Frame Software (Microfire, Goleta, Kalifornien) verwendet wurde. </li></ol> 8. Repräsentative Ergebnisse: Da die Autofluoreszenz von Fischgeweben so hoch ist, wird diese Gewebe erscheinen unter dem Tri-Filter orange, bequem bietet den Hintergrund für die Bakterien. Vor diesem Hintergrund werden die einzelnen FITC gefärbten Bakterien als helle grüne Punkte erscheinen und bei 200X ihre Stabform wird erkennbar sein (Abb. 1). Bad Abschnitte darstellen können falsch-positive (aufgrund eines Problems in der Spül-Phase), in welchem ​​Fall eine große Anzahl von Bakterien zu sein scheinen gleichmäßig auf der Folie präsentieren. <img src="/files/ftp_upload/2687/2687fig1.jpg" alt="Abbildung 1"/> Abbildung 1. Mikroskopische Aufnahme eines Muskels Abschnitte mit zwei E. ictaluri (Pfeile a und b) (200x). BBILDUNG 2 &quot;/&gt; Abbildung 2. Gesamtkonzept des Experiments

<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>

Dieses Protokoll Details eine Technik, die in situ Visualisierung der Welse Erreger Edwardsiella ictaluri in histologischen Schnitten. Um das Beste aus unserer Kenntnis ist dies die erste derartige Protokoll beschrieben. Der wichtigste Schritt, in unserer Erfahrung ist das Spülen der Antikörper wie im Schritt 4.4 der vorliegenden Protokoll als unzureichend Waschen kann sich in der falsch-positiven Ergebnis. Das Hauptproblem bei der Interpretation der Ergebnisse dieser Technik ist die Autofluoreszenz des Gewebes. Es wurde jedoch festgestellt, dass mit dem Tri-Filter meist löste dieses Problem, wie die überwiegende Mehrheit der nicht-spezifischen Fluoreszenz auftreten, die ausserhalb des grün fluoreszierenden Spektrum. Auch während dieser Technik sehr empfindlich ist, kann sie nicht auf niedrige bakterielle Belastungen zu erkennen.

<table border="1"><tbody><tr><th> Name des Reagenzes </th><th> Firma </th><th> Katalog-Nummer </th></tr><tr><td> Gehirn Nährbodenpulver </td><td> Becton Dickinson </td><td> 237200 </td></tr><tr><td> MS222 </td><td> Argent Labs </td><td></td></tr><tr><td> Mausserum </td><td> Cappel </td><td> 55989 </td></tr><tr><td> Ziege anti-Maus-FITC </td><td> Southern Biotech </td><td> 1010-04 </td></tr><tr><td> Permafluor </td><td> Lab Vision </td><td> Ta-030-FM </td></tr><tr><td> Kaliumchlorid (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> Bovine Serum Albumin </td><td> Sigma </td><td> 85040C </td></tr><tr><td> Kaliumphosphat (KH 2 PO 4) </td><td> Sigma </td><td> P-5379 </td></tr><tr><td> Natriumbicarbonat (NaHCO 3) </td><td> Sigma </td><td> S-5761 </td></tr><tr><td> Natriumchlorid (NaCal) </td><td> Sigma </td><td> S-9625 </td></tr><tr><td> Natriumdihydrogenphosphat (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

Während Edwardsiella ictaluri ist ein wichtiger Erreger der Kanal Wels Ictalurus punctatus und wurde vor fast drei Jahrzehnten 1,2 entdeckt, so weit, zu den besten dieser Autoren &quot;Wissen ist keine Methode entwickelt worden, um für die in situ Visualisierung der damit Bakterien in histologischen Schnitten. Während bakterielle Lokalisation in vivo in früheren Studien mit Platte zählt 3, radiometrische markierte 4, oder Biolumineszenz-Bakterien 5 ermittelt wurde, haben die meisten dieser Studien nur auf die Brutto-Orgel Ebene durchgeführt worden, mit einer Ausnahme 6. Diese Einschränkung ist besonders besorgniserregend, weil E. ictaluri hat eine komplexe Infektionszyklus 1,7, und es hat eine Vielzahl von Virulenzfaktoren 8,9. Das komplexe Zusammenspiel von E. ictaluri mit seinem Gastgeber ist in vieler Hinsicht ähnlich zu Salmonella typhi 10, die in der gleichen taxonomischen Familie ist. Hier beschreiben wir eine Technik die es erlaubt die Detektion von Bakterien mittels indirekter Immunhistochemie mit dem monoklonalen Antikörper, der von ED9 Ainsworth et al. 11. Kurz gesagt, ist ein Blockierserum auf Paraffin eingebetteten histologischen Schnitten angewendet, um unspezifische abwartend zu verhindern. E.: Dann werden die Schnitte mit dem primären Antikörper inkubiert ictaluri spezifischen monoklonalen Antikörper ED9. Überschüssige Antikörper werden entfernt und spülte den FITC-markierten Sekundärantikörper hinzugefügt werden. Nach dem Spülen werden die Schnitte mit einem fluoreszierenden spezifischen Eindeckmedium montiert. Diese für den Nachweis von E. erlaubt ictaluri in situ in histologischen Schnitten von Kanal Wels Gewebe.

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

Hier beschreiben wir ein Verfahren auszuarbeiten, die Kennzeichnung von<em&gt; Edwardsiella ictaluri in situ</em&gt; In histologischen Schnitten von Kanal Wels<em&gt; Ictalurus punctatus</em&gt; Mittels indirekter Immunhistochemie mit monoklonalen Antikörpern ED9 als primäre und fluoreszierenden FITC markierte Antikörper als sekundären. Diese für den Nachweis des Bakteriums mit Fluoreszenz-Mikroskopie erlaubt.

Verwendung von fluoreszierenden Immuno-Chemie für den Nachweis von Edwardsiella ictaluri In Kanal Wels ( I. punctatus) Proben

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

Universidad San Sebastian

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 Aufrufe.  Mississippi State University. Hier beschreiben wir ein Verfahren auszuarbeiten, die Kennzeichnung von Edwardsiella ictaluri in situ In histologischen Schnitten von Kanal Wels Ictalurus punctatus Mittels indirekter Immunhistochemie mit monoklonalen Antikörpern ED9 als primäre und fluoreszierenden FITC markierte Antikörper als sekundären. Diese für den Nachweis des Bakteriums mit Fluoreszenz-Mikroskopie erlaubt.

Serie: 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).

Kombination von Klebstoff-tape-basierten Sampling und Fluoreszenz In situ Hybridisierung zum schnellen Nachweis von Salmonellen 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 ...

Forschung

Immunologie und Infektion

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.

Multiplex Nachweis von Bakterien in komplexen Clinical and Environmental Proben mit Oligonukleotid-gekoppelten Fluoreszenz-Mikrosphären

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.

Detektion von fluoreszierenden Nanopartikel Wechselwirkungen mit primären Immun-Zell-Subpopulationen durch Durchflusszytometrie

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.

Die Verwendung von fluoreszierenden Ziel Arrays zur Beurteilung der T-Zell-Antworten<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 ...

Qualitative and Quantitative Assays for Detection and Characterization of Protein Antimicrobials

Initial evaluations of large microbial libraries for potential producers of novel antimicrobial proteins require both qualitative and quantitative methods to screen for target enzymes prior to investing greater research effort and resources. The goal of this protocol is to demonstrate two complementary assays for conducting these initial evaluations. The microslide diffusion assay provides an initial or simple detection screen to enable the qualitative and rapid assessment of proteolytic activity against an array of both viable and heat-killed bacterial target substrates. As a counterpart, the increased sensitivity and reproducibility of the dye-release assay provides a quantitative platform for evaluating and comparing environmental influences affecting the hydrolytic activity of protein antimicrobials. The ability to label specific heat-killed cell culture substrates with Remazol brilliant blue R dye expands this capability to tailor the dye-release assay to characterize enzymatic activity of interest.

Here, we present protocols to rapidly screen and characterize enzymes for antimicrobial activity. The microslide diffusion assay and the dye-release assay utilize target bacterial substrates for qualitative and quantitative enzymatic activity evaluation.

Qualitative und quantitative Assays zur Detektion und Charakterisierung von Protein Antimikrobielle

Initial evaluations of large microbial libraries for potential producers of novel antimicrobial proteins require both qualitative and quantitative methods ...

Fast and Specific Assessment of the Halogenating Peroxidase Activity in Leukocyte-enriched Blood Samples

In this paper a protocol for the quick and standardized enrichment of leukocytes from small whole blood samples is described. This procedure is based on the hypotonic lysis of erythrocytes and can be applied to human samples as well as to blood of non-human origin. The small initial sample volume of about 50 to 100 &#181;l makes this method applicable to recurrent blood sampling from small laboratory animals. Moreover, leukocyte enrichment is achieved within minutes and with low material efforts regarding chemicals and instrumentation, making this method applicable in multiple laboratory environments.
Standardized purification of leukocytes is combined with a highly selective staining method to evaluate halogenating peroxidase activity of the heme peroxidases, myeloperoxidase (MPO) and eosinophil peroxidase (EPO), i.e., the formation of hypochlorous and hypobromous acid (HOCl and HOBr). While MPO is strongly expressed in neutrophils, the most abundant immune cell type in human blood as well as in monocytes, the related enzyme EPO is exclusively expressed in eosinophils. The halogenating activity of these enzymes is addressed by using the almost HOCl- and HOBr-specific dye aminophenyl fluorescein (APF) and the primary peroxidase substrate hydrogen peroxide. Upon subsequent flow cytometry analysis all peroxidase-positive cells (neutrophils, monocytes, eosinophils) are distinguishable and their halogenating peroxidase activity can be quantified. Since APF staining may be combined with the application of cell surface markers, this protocol can be extended to specifically address leukocyte sub-fractions. The method is applicable to detect HOCl and HOBr production both in human and in rodent leukocytes.
Given the widely and diversely discussed immunological role of these enzymatic products in chronic inflammatory diseases, this protocol may contribute to a better understanding of the immunological relevance of leukocyte-derived heme peroxidases.

This protocol describes the quick enrichment of leukocytes from small blood samples for a subsequent specific determination of the halogenating peroxidase activity within the cells. The method can be applied to human and non-human material and may contribute to the evaluation of new inflammatory markers.

Schnelle und spezifische Bewertung der Halogenierungsagentien Peroxidaseaktivität in Leukozyten angereicherte Blutproben

In this paper a protocol for the quick and standardized enrichment of leukocytes from small whole blood samples is described. This procedure is based on ...

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.

Magnetrührers Verfahren zum Nachweis von<em&gt; Trichinella</em&gt; Larvae in Muskelproben

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).

Schnelle, sichere und einfache manuelle am Krankenbett Nukleinsäure-Extraktion für den Nachweis des Virus in Vollblut-Proben

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.

Eine High-Throughput-Plattform für das Screening von 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.

Gemultiplexten fluoreszierende immunhistochemische Färbung, Bildverarbeitung und Analyse in histologischen Proben des Lymphoms

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