Ce travail a été financé par une subvention du Conseil de recherches en génie du Canada en sciences naturelles et (CRSNG, accorder aucune 298515-2011). AL est le récipiendaire d&#39;un doctorat bourse du Conseil de recherches en génie du Canada (CRSNG) en sciences naturelles et, MS et a été soutenu par une subvention des Instituts de recherche en santé du Canada (IRSC, accorde pas. MOP123246).

Toutes les procédures ont été effectuées en conformité avec le Conseil canadien sur les lignes directrices des soins des animaux après l&#39;approbation par le Comité institutionnel de protection des animaux du Centre de recherche du Centre hospitalier de l&#39;Université de Montréal (CRCHUM). 1. Isolement, identification, et de la culture des macrophages murins péritonéale <ol><li> Préparer le milieu thioglycollate de 3,8% brasseur. Pour ce faire, suspendre 38 g de milieu au thioglycolate dans 1000 ml d&#39;eau distillée. Apportez solution à ébullition pour dissoudre complètement le milieu. Stériliser par autoclavage à 121 ° C pendant 15 min. Stockez jusqu&#39;à trois mois dans l&#39;obscurité, à température ambiante 18. NOTE: Jeter si la turbidité développe ce qui indique une contamination bactérienne. La solution peut être conservée pendant jusqu&#39;à un an dans l&#39;obscurité si gardé stérile. </li><li> Utilisation de seringues de 1 ml attachés à 23 G aiguilles, injecter 1 ml de 3,8% Brewer thioglycollate moyenne dans la cavité péritonéale de chaque mousoi et attendre pendant 3 jours. Utilisez nouvelle seringue et une aiguille pour chaque souris. </li><li> Anesthésier les souris par injection intraperitoneale de pentobarbital sodique (100 mg / kg) et euthanasie les souris par dislocation cervicale. Confirmez anesthésie appropriée en cochant la fréquence respiratoire. Habituellement respirations rapides indiquent que la souris est pas profondément anesthésié. </li><li> Laver l&#39;abdomen de chaque souris avec 70% d&#39;éthanol. En utilisant une paire de ciseaux, réaliser une incision latérale le long de la ligne médiane inférieure du péritoine. </li><li> En utilisant une pince, retirer la peau abdominale pour exposer la peau péritonéale transparent. Utilisation de seringues de 5 ml attachés à aiguilles 20 G, injecter 5 ml de DPBS froid dans la cavité peritoneale de chaque souris. </li><li> Effectuer un massage doux sur la cavité péritonéale puis aspirer soigneusement le liquide sans perforer un organe. Retirez l&#39;aiguille et distribuer le liquide péritonéal en tubes de 50 ml de centrifugation coniques. </li><li> Centrifuger pendant 10 min à 400 g dans une centrifugeuse réfrigérée.Les cellules doivent rester froid pendant toute la procédure. Rejeter le surnageant et remettre en suspension culot cellulaire dans un milieu RPMI 1640. </li><li> En utilisant un hémocytomètre, et compter les cellules à ajuster la densité des cellules à 1 x 10 6 cellules / ml. </li><li> Caractériser le phénotype des cellules isolées par cytométrie de flux en utilisant 1 x 10 6 cellules par souris contre antibodie et F4 / 80 (un antigène de surface exprimé sur les macrophages). </li></ol> 2. Traitements cellulaires <ol><li> Directement, après isolement, ajouter 1 x 10 6 cellules dans chaque puits. Laissez les macrophages péritonéaux murins à adhérer dans des plaques à 6 puits en les cultivant pendant 1-2 heures à 37 ° C. Éliminer les cellules non-adhérentes en lavant doucement 3 fois avec du PBS chaud. </li><li> Par la suite, des cellules en culture dans du DMEM exempt de sérum 900 ul pendant 24 heures en présence des ligands de TLR suivants: (PAM3CSK4-TLR1 / 2 (0,5 mg / ml); le poly (I: C) -TLR3 (10 mg / ml) ; LPS-TLR4 (100 ng / ml); flagelline au TLR5 (100 ng / ml); FLS1-TLR6 / 2 (100 ng / ml); ssRNA40-TLR7 (1 ug / ml); ODN1826-TLR9 (1 uM). NOTE: Préparer pour chaque ligand une solution 10x de stock. Ajouter 100 ul de celle-ci dans chaque puits, effectuant ainsi une dilution de 10 fois. </li></ol> 3. Isolement de l&#39;ARN <ol><li> Retirer toutes les cellules du milieu et lyse directement dans les plaques à six puits par addition de 1 ml de TRIzol dans chaque puits et le passage du lysat de cellules plusieurs fois à travers une pipette. Incuber les échantillons homogénéisés pendant 5 à 10 min à la température ambiante, afin de permettre la dissociation complète des complexes de nucléoprotéine. </li><li> Transfert lysat dans 1,5 ml RNase- et microtubes DNase. Ajouter 0,2 ml de chloroforme par 1ml TRIzol. Agiter les tubes vigoureusement à la main pendant 15 secondes et les incuber à température ambiante pendant 5 à 10 min. Centrifugeuse à 12.000 g pendant 15 min à 4 ° C. Observer le mélange se séparer en une phase rouge (phénol-chloroforme) inférieur, une interphase et une phase aqueuse supérieure incolore. ARN reste exclusivement dans la phase aqueuse. </li><li> Transfer attentivement la phase aqueuse supérieure dans un nouveau tube sans perturber l&#39;interphase. Précipiter l&#39;ARN de celui-ci par mélange avec 0,5 ml d&#39;alcool isopropylique. Incuber les échantillons à température ambiante pendant 10 min et centrifugation à 12 000 xg pendant 10 min à 4 ° C. L&#39;ARN précipités formant un culot blanc sur le côté et le bas du tube. </li><li> Retirer le surnageant. Laver le culot une fois avec de l&#39;ARN 1 ml d&#39;éthanol à 75%. Mélanger les échantillons par vortex et centrifuger à 7500 g pendant 5 min à 4 ° C. Brièvement sécher l&#39;ARN (de sécher à l&#39;air pendant 10 min). Dissoudre ARN dans 0,1 ml DEPC (RNAse d&#39;eau libre) et incuber pendant 10 min à 55 ° C. </li><li> Quantifier l&#39;ARN en utilisant un spectrophotomètre. Pour ce faire, diluer les échantillons 100 fois dans de l&#39;eau DEPC et lire à longueurs d&#39;onde de 260 nm. La concentration d&#39;ARN est alors: OD 260 x 40 ng / ul x facteur de dilution. </li><li> Egaliser concentrations d&#39;ARN et de synthétiser l&#39;ADNc selon les instructions du fabricant en utilisant système RT-PCR pour trousse de premiers-Strand cDNA Synthesis. Commeselon les instructions du fabricant, de mesurer les niveaux d&#39;ARNm du gène par PCR en temps réel (45 cycles) dans un système de détection de l&#39;ADN en temps réel. Normaliser les niveaux d&#39;expression des gènes avec deux gènes de ménage par exemple β-actine et GAPDH. REMARQUE: Normaliser concentration d&#39;ARN à 500 ng / ml et en utilisant 0,5 ug pour la synthèse d&#39;ADNc. </li></ol>

<ol>
	<li>Pollard, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trophic+macrophages+in+development+and+disease.">Trophic macrophages in development and disease.</a> Nat Rev Immunol. 9 (4), 259-270 (2009).</li><li>Gordon, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alternative+activation+of+macrophages.">Alternative activation of macrophages.</a> Nat Rev Immunol. 3 (1), 23-35 (2003).</li><li>Koury, M. J., Ponka, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+insights+into+erythropoiesis:+the+roles+of+folate,+vitamin+B12,+and+iron.">New insights into erythropoiesis: the roles of folate, vitamin B12, and iron.</a> Annu Rev Nutr. 24, 105-131 (2004).</li><li>Sheftel, A. D., Kim, S. F., Ponka, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-heme+induction+of+heme+oxygenase-1+does+not+alter+cellular+iron+metabolism.">Non-heme induction of heme oxygenase-1 does not alter cellular iron metabolism.</a> J Biol Chem. 282 (14), 10480-10486 (2007).</li><li>Hershko, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Storage+iron+regulation.">Storage iron regulation.</a> Prog Hematol. 10, 105-148 (1977).</li><li>Collins, H. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Withholding+iron+as+a+cellular+defence+mechanism--friend+or+foe.">Withholding iron as a cellular defence mechanism--friend or foe.</a> Eur J Immunol. 38 (7), 1803-1806 (2008).</li><li>Noyes, W. D., Bothwell, T. H., Finch, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+the+reticulo-endothelial+cell+in+iron+metabolism.">The role of the reticulo-endothelial cell in iron metabolism.</a> Br J Haematol. 6, 43-55 (1960).</li><li>Layoun, A., Huang, H., Calve, A., Santos, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toll-like+receptor+signal+adaptor+protein+MyD88+is+required+for+sustained+endotoxin-induced+acute+hypoferremic+response+in+mice.">Toll-like receptor signal adaptor protein MyD88 is required for sustained endotoxin-induced acute hypoferremic response in mice.</a> Am J Pathol. 180 (6), 2340-2350 (2012).</li><li>Zumerle, S., 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=Targeted+disruption+of+hepcidin+in+the+liver+recapitulates+the+hemochromatotic+phenotype.">Targeted disruption of hepcidin in the liver recapitulates the hemochromatotic phenotype.</a> Blood. 123 (23), 3646-3650 (2014).</li><li>Nguyen, N. B., Callaghan, K. D., Ghio, A. J., Haile, D. J., Yang, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepcidin+expression+and+iron+transport+in+alveolar+macrophages.">Hepcidin expression and iron transport in alveolar macrophages.</a> Am J Physiol Lung Cell Mol Physiol. 291 (3), L417-L425 (2006).</li><li>Nemeth, 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=Hepcidin,+a+putative+mediator+of+anemia+of+inflammation,+is+a+type+II+acute-phase+protein.">Hepcidin, a putative mediator of anemia of inflammation, is a type II acute-phase protein.</a> Blood. 101 (7), 2461-2463 (2003).</li><li>Nemeth, 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=Hepcidin+regulates+cellular+iron+efflux+by+binding+to+ferroportin+and+inducing+its+internalization.">Hepcidin regulates cellular iron efflux by binding to ferroportin and inducing its internalization.</a> Science. 306 (5704), 2090-2093 (2004).</li><li>Constante, 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=Distinct+requirements+for+Hfe+in+basal+and+induced+hepcidin+levels+in+iron+overload+and+inflammation.">Distinct requirements for Hfe in basal and induced hepcidin levels in iron overload and inflammation.</a> Am J Physiol Gastrointest Liver Physiol. 291 (2), G229-G237 (2006).</li><li>Zhang, X., Goncalves, R., Mosser, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+isolation+and+characterization+of+murine+macrophages.">The isolation and characterization of murine macrophages.</a> Curr Protoc Immunol. Chapter 14 (Unit 14 11), (2008).</li><li>Ray, A., Dittel, B. N. <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+mouse+peritoneal+cavity+cells.">Isolation of mouse peritoneal cavity cells.</a> J Vis Exp. (35), (2010).</li><li>Leijh, P. C., van Zwet, T. L., ter Kuile, M. N., van Furth, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+thioglycolate+on+phagocytic+and+microbicidal+activities+of+peritoneal+macrophages.">Effect of thioglycolate on phagocytic and microbicidal activities of peritoneal macrophages.</a> Infect Immun. 46 (2), 448-452 (1984).</li><li>Dy, M., Debray-Sachs, M., Kamoun, P., Hamburger, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+thioglycollate+on+macrophage+lysosomal+enzymes.">Effect of thioglycollate on macrophage lysosomal enzymes.</a> Biomedicine. 29 (5), 167-170 (1978).</li><li>Li, Y. M., Baviello, G., Vlassara, H., Mitsuhashi, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glycation+products+in+aged+thioglycollate+medium+enhance+the+elicitation+of+peritoneal+macrophages.">Glycation products in aged thioglycollate medium enhance the elicitation of peritoneal macrophages.</a> J Immunol Methods. 201 (2), 183-188 (1997).</li><li>Layoun, A., Santos, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bacterial+cell+wall+constituents+induce+hepcidin+expression+in+macrophages+through+MyD88+signaling.">Bacterial cell wall constituents induce hepcidin expression in macrophages through MyD88 signaling.</a> Inflammation. 35 (4), 1500-1506 (2012).</li><li>Oppenheim, J. J., Yang, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alarmins:+chemotactic+activators+of+immune+responses.">Alarmins: chemotactic activators of immune responses.</a> Curr Opin Immunol. 17 (4), 359-365 (2005).</li><li>Akira, S., Uematsu, S., Takeuchi, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathogen+recognition+and+innate+immunity.">Pathogen recognition and innate immunity.</a> Cell. 124 (4), 783-801 (2006).</li><li>Lang, R., Patel, D., Morris, J. J., Rutschman, R. L., Murray, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Shaping+gene+expression+in+activated+and+resting+primary+macrophages+by+IL-10.">Shaping gene expression in activated and resting primary macrophages by IL-10.</a> J Immunol. 169 (5), 2253-2263 (2002).</li><li>Wang, C., 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=Characterization+of+murine+macrophages+from+bone+marrow,+spleen+and+peritoneum.">Characterization of murine macrophages from bone marrow, spleen and peritoneum.</a> BMC Immunol. 14 (6), (2013).</li><li>Austin, P. E., McCulloch, E. A., Till, 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=Characterization+of+the+factor+in+L-cell+conditioned+medium+capable+of+stimulating+colony+formation+by+mouse+marrow+cells+in+culture.">Characterization of the factor in L-cell conditioned medium capable of stimulating colony formation by mouse marrow cells in culture.</a> J Cell Physiol. 77 (2), 121-134 (1971).</li><li>Cannon, G. J., Swanson, 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=The+macrophage+capacity+for+phagocytosis.">The macrophage capacity for phagocytosis.</a> J Cell Sci. 101 (Pt 4), 907-913 (1992).</li><li>Wang, Y., Harris, D. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophages+in+renal+disease.">Macrophages in renal disease.</a> J Am Soc Nephrol. 22 (1), 21-27 (2011).</li><li>Edwards, J. P., Zhang, X., Frauwirth, K. A., Mosser, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biochemical+and+functional+characterization+of+three+activated+macrophage+populations.">Biochemical and functional characterization of three activated macrophage populations.</a> J Leukoc Biol. 80 (6), 1298-1307 (2006).</li><li>Hoover, D. L., Nacy, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+activation+to+kill+Leishmania+tropica:+defective+intracellular+killing+of+amastigotes+by+macrophages+elicited+with+sterile+inflammatory+agents.">Macrophage activation to kill Leishmania tropica: defective intracellular killing of amastigotes by macrophages elicited with sterile inflammatory agents.</a> J Immunol. 132 (3), 1487-1493 (1984).</li><li>Schleicher, U., Bogdan, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+culture+and+flow-cytometric+characterization+of+primary+mouse+macrophages.">Generation culture and flow-cytometric characterization of primary mouse macrophages.</a> Methods Mol Biol. 531, 203-224 (2009).</li></ol>

The authors have no competing financial interests.

Les macrophages sont cruciales pour la survie et fournissent une cible tentante pour manipuler l&#39;hôte pour objectifs immunologiques. La découverte des TLR et d&#39;autres molécules de reconnaissance ont mené les macrophages au centre du débat immunologique. Les macrophages répondre à une variété de stimuli, y compris des cytokines, des molécules associées à des dommages moléculaires amortit motif (20) et des molécules associées à des groupes d&#39;agents pathogènes (PAMP) 21. C...

Le système réticulo-endothélial phagocytaire est composé de cellules dans différents tissus et organes tels que la moelle osseuse, le sang, le foie et la rate. Les macrophages sont largement distribués autour du corps, où ils participent notamment à des innées et adaptatives des réponses immunitaires à contrôler et infections claires. En plus de leur rôle dans la défense de l&#39;hôte, les macrophages jouent également un rôle important dans la cicatrisation des plaies et dans le maintien de l&#39;homéostasie tissulaire 1,2. En outre, les macrophages ne sont pas seulement importants pour la fonction immunitaire, mais participent aussi activement à l&#39;homéostasie du fer 3. Dans le corps, environ 80% de fer est présent en hémoglobine dans les erythrocytes, qui, lorsqu&#39;il est sénescente sont phagocytés par les macrophages 4. Quotidien, ces macrophages recyclent 25 mg de fer érythrocytaire dérivés et fournissent son transport dans le plasma 5. En outre, lors de l&#39;infection et l&#39;inflammation, les macrophages pro-inflammatoires séquestrent le fer sérique de réduire availabili de ferty aux pathogènes, aux niveaux systémiques et locaux 6-8. En outre, des études ont montré que les macrophages et hépatocytes produisent principalement un peptide antimicrobien appelé hepcidine qui est considéré comme le maître régulateur du métabolisme du fer 9, 10. L&#39;hepcidine est principalement augmenté par des stimuli inflammatoires et est partiellement responsable de la séquestration du fer dans les macrophages sur l&#39;inflammation chronique 11-13. Comme expression de l&#39;hepcidine dans les macrophages est pas très bien compris, nous avons étudié le rôle possible des récepteurs Toll-like (TLR) dans le présent règlement. Les TLR se trouvent principalement sur les macrophages et jouent un rôle central dans leur activation. En outre, le LPS induit l&#39;expression de l&#39;hepcidine dans le foie dépend de TLR4 13. Par conséquent, pour exécuter notre étude, nous avons utilisé une méthode basée sur l&#39;isolement des macrophages péritonéaux murins. lignées de cellules macrophages sont largement utilisés dans le goujon macrophagess; néanmoins culture prolongée peut provoquer la perte du gène et une diminution de la fonction immunitaire dans ces lignées cellulaires. Ainsi, l&#39;isolement des macrophages de la cavité péritonéale est crucial. La cavité péritonéale de la souris présente un site idéal pour la récolte macrophages 13-15. Macrophages péritonéaux murins isolés sont commode pour plusieurs études concernant leur fonction immunologique. Cependant, le nombre de macrophages dans le péritoine est insuffisante pour des études approfondies et est estimée à environ 1 x 10 6 par souris, des macrophages. Ainsi, pour augmenter la production de macrophages, un agent provoquant stérile tel que de thioglycolate ont été injectés dans la cavité péritonéale précédant la récolte des cellules. Après injection thioglycollate, le rendement des macrophages par souris a été augmenté de 10 fois. Malgré l&#39;augmentation du rendement des macrophages, des actes moyennes thioglycollate Brewer comme un irritant qui induit une réponse inflammatoire, résultant dans le recrutement des macrophages, qui may mais pas nécessaire affectent l&#39;expression des gènes. Par conséquent, un groupe de contrôle constitué de macrophages non traités doit être inclus dans chaque expérience. En nos mains, l&#39;hepcidine expression qui est fortement stimulée par l&#39;inflammation n&#39;a pas été détecté dans thioglycolate non traité suscité des macrophages péritonéaux. En outre, des études ont montré que la thioglycollate Brewer recrute de nombreux macrophages, mais ne les active pas 16. D&#39;autre part, le thioglycolate de Brewer a suscité macrophages ont montré une augmentation des enzymes lysosomales, mais une diminution de tuer les microorganismes ingérés 17. Cependant, la capacité de phagocytose n&#39;a pas été affectée par rapport aux macrophages non provoquée 16. Une fois cultivées dans des boîtes, les macrophages péritonéaux deviennent adhérentes, permettant ainsi leur séparation d&#39;avec d&#39;autres types de cellules isolées à partir de la cavité péritonéale. Par la suite, les macrophages isolés ont été exposés à différents agonistes TLR.Enfin, l&#39;ARNm a été extrait des cellules cultivées et l&#39;expression des gènes a été analysée en utilisant une réaction en chaîne transcriptase-polymerase inverse quantitative (qRT-PCR).

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>C57BL/6 mice</td>
			<td>Charles River Laboratories, Inc. (Wilmington, MA, USA)</td>
			<td>475</td>
			<td></td>
		</tr>
		<tr>
			<td>Thioglycollate</td>
			<td>Sigma-Aldrich, (St. Louis, MO)</td>
			<td>19032-500G</td>
			<td></td>
		</tr>
		<tr>
			<td>70% ethanol</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>10% sodium pentobarbital (Used for mice anesthesia (80 mg/kg, i.p.))</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dulbecco&#8217;s phosphate-buffered saline (DPBS), placed on ice and will serve to harvest macrophages</td>
			<td>WISENT INC Canada (QC)</td>
			<td>311-425-CL</td>
			<td></td>
		</tr>
		<tr>
			<td>RPMI medium 1640 (Supplement with penicillin, streptomycin, L-glutamine, and 10 % fetal calf serum).</td>
			<td>WISENT INC Canada (QC)</td>
			<td>350-000-CL</td>
			<td></td>
		</tr>
		<tr>
			<td>1 and 5 ml syringes</td>
			<td>BD USA (NJ)</td>
			<td>309659</td>
			<td></td>
		</tr>
		<tr>
			<td>Six-well plates</td>
			<td>Corning Incorporated (NY, USA)</td>
			<td>MCT-150-C</td>
			<td></td>
		</tr>
		<tr>
			<td>Bacterial lipoprotein Pam3CSK4 (0.5 mg/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLRL-pm25</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyionosine&#8211;polycytidylic acid (Poly(I:C)) (10 mg/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLRL-PIC</td>
			<td></td>
		</tr>
		<tr>
			<td>LPS from Escherichia coli 055:B5 (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>L2880</td>
			<td></td>
		</tr>
		<tr>
			<td>Purified flagellin from Salmonella typhimurium (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-FLIC-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipoprotein synthetic FSL1 (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-FSL</td>
			<td></td>
		</tr>
		<tr>
			<td>ssRNA derived from the HIV-1 long terminal repeat ssRNA40 (1 &#956;g/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-LRNA-40</td>
			<td></td>
		</tr>
		<tr>
			<td>Type B CpG oligonucleotide ODN1826 (1 &#956;M)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>11B16-MM</td>
			<td></td>
		</tr>
		<tr>
			<td>TRIZOL</td>
			<td>Invitrogen, (Burlington, ON, Canada)</td>
			<td>15596-026</td>
			<td></td>
		</tr>
		<tr>
			<td>20g and 23g needles</td>
			<td>BD USA (NJ)</td>
			<td>305175</td>
			<td></td>
		</tr>
		<tr>
			<td>Scissor</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Forceps</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>50 ml conical tubes placed on ice</td>
			<td>Sarstedt (Newton, MA, USA)</td>
			<td>62.547.205</td>
			<td></td>
		</tr>
		<tr>
			<td>Red Blood Cells Lysis Buffer</td>
			<td>Sigma-Aldrich, (St. Louis, MO)</td>
			<td>R7757-100ML</td>
			<td></td>
		</tr>
		<tr>
			<td>Refrigerated centrifuge</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hemocytometer</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>F4/80 antibody</td>
			<td>BIO-RAD ( CA, USA)</td>
			<td>MCA497APC</td>
			<td></td>
		</tr>
		<tr>
			<td>CD16/CD32 antibodies</td>
			<td>Pharmingen, {Mississauga, ON, CA)</td>
			<td>553141</td>
			<td></td>
		</tr>
		<tr>
			<td>Flow Cytometer</td>
			<td>Coulter Epics Elite counter, Coulter, (Hialeah, FL,USA)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Six-well plates</td>
			<td>Corning Incorporated (NY, USA)</td>
			<td>MCT-150-C</td>
			<td></td>
		</tr>
		<tr>
			<td>Bacterial lipoprotein Pam3CSK4 (0.5 mg/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLRL-pm25</td>
			<td></td>
		</tr>
		<tr>
			<td>Polyionosine&#8211;polycytidylic acid (Poly(I:C)) (10 mg/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLRL-PIC</td>
			<td></td>
		</tr>
		<tr>
			<td>LPS from Escherichia coli 055:B5 (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>L2880</td>
			<td></td>
		</tr>
		<tr>
			<td>Purified flagellin from Salmonella typhimurium (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-FLIC-10</td>
			<td></td>
		</tr>
		<tr>
			<td>Lipoprotein synthetic FSL1 (100 ng/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-FSL</td>
			<td></td>
		</tr>
		<tr>
			<td>ssRNA derived from the HIV-1 long terminal repeat ssRNA40 (1 &#956;g/ml)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>TLR-LRNA-40</td>
			<td></td>
		</tr>
		<tr>
			<td>Type B CpG oligonucleotide ODN1826 (1 &#956;M)</td>
			<td>InvivoGen (San Diego, USA)</td>
			<td>11B16-MM</td>
			<td></td>
		</tr>
		<tr>
			<td>TRIZOL</td>
			<td>Invitrogen, (Burlington, ON, Canada)</td>
			<td>15596-026</td>
			<td></td>
		</tr>
		<tr>
			<td>1.5 ml Eppendorf tubes</td>
			<td>Axygen Scietific (CA,USA)</td>
			<td>3516</td>
			<td></td>
		</tr>
		<tr>
			<td>Chloroform</td>
			<td>Fisher Scientific (ON, Canada)</td>
			<td>UN1888</td>
			<td></td>
		</tr>
		<tr>
			<td>Isopropyl alcohol</td>
			<td>JT Baker (PA, USA)</td>
			<td>70566</td>
			<td></td>
		</tr>
		<tr>
			<td>75% ethanol (in DEPC treated water)</td>
			<td>Commercial Alchohols (QC, Canada)</td>
			<td>17394</td>
			<td></td>
		</tr>
		<tr>
			<td>0.01% diethyl pyrocarbonate (DEPC) treated water (let stand overnight and autoclave)</td>
			<td>Sigma-Aldrich, (St. Louis, MO)</td>
			<td>216.542.8</td>
			<td></td>
		</tr>
		<tr>
			<td>Omniscript RT-PCR system</td>
			<td>Qiagen, (Mississauga, ON, Canada)</td>
			<td>205113</td>
			<td></td>
		</tr>
		<tr>
			<td>Rotor Gene 3000</td>
			<td>Montreal Biotech, (Kirkland, QC, Canada)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>QuantiTect SYBR Green I PCR kits</td>
			<td>Qiagen, (Mississauga, ON, Canada)</td>
			<td>204141</td>
			<td></td>
		</tr>
	</tbody>
</table>

isolation of murine peritoneal macrophages to carry out gene expression analysis upon toll-like receptors stimulation

Lors de l&#39;infection et l&#39;inflammation, les monocytes circulants quittent la circulation sanguine et migrent dans les tissus, où ils se différencient en macrophages. Les macrophages expriment des récepteurs de surface Toll-like (TLR), qui reconnaissent des motifs moléculaires conservés à travers l&#39;évolution dans une large gamme de micro-organismes. TLR jouent un rôle central dans l&#39;activation des macrophages qui est généralement associée à l&#39;expression du gène altération. Les macrophages sont essentiels dans de nombreuses maladies et sont apparus comme des cibles attrayantes pour la thérapie. Dans le protocole suivant, nous décrivons une procédure d&#39;isoler les macrophages péritonéaux murins en utilisant un milieu thioglycollate de Brewer. Ce dernier va stimuler la migration des monocytes dans le péritoine, en conséquence, cela posera des macrophages rendement de 10 fois. Plusieurs études ont été effectuées en utilisant la moelle osseuse, la rate ou péritonéale macrophages dérivés. Toutefois, les macrophages péritonéaux sont avérés plus mature sur l&#39;isolement et sont plus stables dans leur fonctionnellité et le phénotype. Ainsi, macrophages isolés de la cavité péritonéale murin présentent une population de cellules importantes qui peuvent servir dans différentes études immunologiques et métaboliques. Une fois isolé, les macrophages ont été stimulées avec les différents ligands de TLR et par conséquent l&#39;expression génique a été évaluée.

Nous avons caractérisé les premier macrophages péritonéaux murins isolés par cytométrie de flux. Pour ce faire, nous avons utilisé (F4 / 80) anticorps qui reconnaissent spécifiquement des marqueurs seulement exprimées par les macrophages. Cette caractérisation est nécessaire pour déterminer le pourcentage de macrophages isolés et de les distinguer entre les cellules obtenues au cours du processus d&#39;isolement. Comme le montre la (figure 1), le pourcentage de cellules exprimant l&#39;anti...

Watch this Scientific Journal Video about Isolation of Murine Peritoneal Macrophages to Carry Out Gene Expression Analysis Upon Toll-like Receptors Stimulation at JoVE.com

Isolation of Murine Peritoneal Macrophages to Carry Out Gene Expression Analysis Upon Toll-like Receptors Stimulation

We describe here a simple protocol to isolate murine peritoneal macrophages. This procedure is followed by RNA extraction to carry out gene expression analysis upon Toll-like receptors stimulation.

Isolement d&#39;anticorps murins péritonéale macrophages pour effectuer Analyse expression génique Sur Toll-like récepteurs Stimulation

During infection and inflammation, circulating monocytes leave the bloodstream and migrate into tissues, where they differentiate into macrophages. ...

isolation-murine-peritoneal-macrophages-to-carry-out-gene-expression

Research

JoVE Journal

Immunology and Infection

36.0K vues.  Institut du cancer de Montréal. We describe here a simple protocol to isolate murine peritoneal macrophages. This procedure is followed by RNA extraction to carry out gene expression analysis upon Toll-like receptors stimulation.

Vidéo: Isolation of Murine Peritoneal Macrophages to Carry Out Gene Expression Analysis Upon Toll-like Receptors Stimulation

Isolation of Mouse Peritoneal Cavity Cells

The peritoneal cavity is a membrane-bound and fluid-filled abdominal cavity of mammals, which contains the liver, spleen, most of the gastro-intestinal tract and other viscera. It harbors a number of immune cells including macrophages, B cells and T cells. The presence of a high number of na&iuml;ve macrophages in the peritoneal cavity makes it a preferred site for the collection of na&iuml;ve tissue resident macrophages (1). The peritoneal cavity is also important to the study of B cells because of the presence of a unique peritoneal cavity-resident B cell subset known as B1 cells in addition to conventional B2 cells. B1 cells are subdivided into B1a and B1b cells, which can be distinguished by the surface expression of CD11b and CD5. B1 cells are an important source of natural IgM providing early protection from a variety of pathogens (2-4). These cells are autoreactive in nature (5), but how they are controlled to prevent autoimmunity is still not understood completely. On the contrary, CD5+ B1a cells possess some regulatory properties by virtue of their IL-10 producing capacity (6). Therefore, peritoneal cavity B1 cells are an interesting cell population to study because of their diverse function and many unaddressed questions associated with their development and regulation. The isolation of peritoneal cavity resident immune cells is tricky because of the lack of a defined structure inside the peritoneal cavity. Our protocol will describe a procedure for obtaining viable immune cells from the peritoneal cavity of mice, which then can be used for phenotypic analysis by flow cytometry and for different biochemical and immunological assays.

The peritoneal cavity in mammals contains different immune cell populations crucial for innate immune responses. An efficient isolation method is required for biochemical and functional analyses of these cells. Here we provide a comprehensive method for the isolation of peritoneal cavity cells in the mouse.

L&#39;isolement des cellules de souris cavité péritonéale

The peritoneal cavity is a membrane-bound and fluid-filled abdominal cavity of mammals, which contains the liver, spleen, most of the gastro-intestinal ...

Recherche

Immunologie et infection

Detection of  Neu1 Sialidase Activity in Regulating TOLL-like Receptor Activation

Mammalian Toll-like receptors (TLRs) are a family of receptors that recognize pathogen-associated molecular patterns. Not only are TLRs crucial sensors of microbial (e.g., viruses, bacteria and parasite) infections, they also play an important role in the pathophysiology of infectious diseases, inflammatory diseases, and possibly in autoimmune diseases. Thus, the intensity and duration of TLR responses against infectious diseases must be tightly controlled. It follows that understanding the structural integrity of sensor receptors, their ligand interactions and signaling components is essential for subsequent immunological protection. It would also provide important opportunities for disease modification through sensor manipulation. Although the signaling pathways of TLR sensors are well characterized, the parameters controlling interactions between the sensors and their ligands still remain poorly defined. We have recently identified a novel mechanism of TLR activation by its natural ligand, which has not been previously observed 1,2. It suggests that ligand-induced TLR activation is tightly controlled by Neu1 sialidase activation. We have also reported that Neu1 tightly regulates neurotrophin receptors like TrkA and TrkB 3, which involve Neu1 and matrix metalloproteinase-9 (MMP-9) cross-talk in complex with the receptors 4. The sialidase assay has been initially use to find a novel ligand, thymoquinone, in the activation of Neu4 sialidase on the cell surface of macrophages, dendritic cells and fibroblast cells via GPCR G&alpha;i proteins and MMP-9 5. For TLR receptors, our data indicate that Neu1 sialidase is already in complex with TLR-2, -3 and -4 receptors, and is induced upon ligand binding to either receptor. Activated Neu1 sialidase hydrolyzes sialyl &alpha;-2,3-linked &beta;-galactosyl residues distant from ligand binding to remove steric hinderance to TLR-4 dimerization, MyD88/TLR4 complex recruitment, NFkB activation and pro-inflammatory cell responses. In a collaborative report, Neu1 sialidase has been shown to regulate phagocytosis in macrophage cells 6. Taken together, the sialidase assay has provided us with powerful insights to the molecular mechanisms of ligand-induced receptor activation. Although the precise relationship between Neu1 sialidase and the activation of TLR, Trk receptors has yet to be fully elucidated, it would represent a new or pioneering approach to cell regulation pathways.

The sialidase assay is a simple technical approach that will elucidate novel molecular mechanism(s) of TLR sensors of microbial infections and involvement in inflammatory diseases at the receptor level on the cell surface of live macrophages.

Détection de Neu1 activité sialidase dans la régulation activation du récepteur Toll-like

Mammalian Toll-like receptors (TLRs) are a family of receptors that recognize pathogen-associated molecular patterns. Not only are TLRs crucial sensors of ...

Quantitative Imaging of Lineage-specific Toll-like Receptor-mediated Signaling in Monocytes and Dendritic Cells from Small Samples of Human Blood

Individual variations in immune status determine responses to infection and contribute to disease severity and outcome. Aging is associated with an increased susceptibility to viral and bacterial infections and decreased responsiveness to vaccines with a well-documented decline in humoral as well as cell-mediated immune responses1,2. We have recently assessed the effects of aging on Toll-like receptors (TLRs), key components of the innate immune system that detect microbial infection and trigger antimicrobial host defense responses3. In a large cohort of healthy human donors, we showed that peripheral blood monocytes from the elderly have decreased expression and function of certain TLRs4 and similar reduced TLR levels and signaling responses in dendritic cells (DCs), antigen-presenting cells that are pivotal in the linkage between innate and adaptive immunity5. We have shown dysregulation of TLR3 in macrophages and lower production of IFN by DCs from elderly donors in response to infection with West Nile virus6,7. 
Paramount to our understanding of immunosenescence and to therapeutic intervention is a detailed understanding of specific cell types responding and the mechanism(s) of signal transduction. Traditional studies of immune responses through imaging of primary cells and surveying cell markers by FACS or immunoblot have advanced our understanding significantly, however, these studies are generally limited technically by the small sample volume available from patients and the inability to conduct complex laboratory techniques on multiple human samples. ImageStream combines quantitative flow cytometry with simultaneous high-resolution digital imaging and thus facilitates investigation in multiple cell populations contemporaneously for an efficient capture of patient susceptibility. Here we demonstrate the use of ImageStream in DCs to assess TLR7/8 activation-mediated increases in phosphorylation and nuclear translocation of a key transcription factor, NF-&kappa;B, which initiates transcription of numerous genes that are critical for immune responses8. Using this technology, we have also recently demonstrated a previously unrecognized alteration of TLR5 signaling and the NF-&kappa;B pathway in monocytes from older donors that may contribute to altered immune responsiveness in aging9.

We describe use of ImageStream technology (<a href="http://www.amnis.com/" target="_blank">www.amnis.com</a>), which combines quantitative flow cytometry with simultaneous high-resolution digital imaging, to quantify cellular mechanisms of primary immune cells from well-defined patient cohorts. Our studies provide a blueprint for translational investigations to quantify lineage specific cellular responses in small samples from subject cohorts.

Imagerie quantitative de Lineage spécifiques Toll-like Receptor la signalisation médiée par les monocytes et les cellules dendritiques à partir de petits échantillons de sang humain

Individual variations in immune status determine responses to infection and contribute to disease severity and outcome.  Aging is associated with an ...

Isolation, Processing and Analysis of Murine Gingival Cells

We have developed a technique to precisely isolate and process murine gingival tissue for flow cytometry and molecular studies. The gingiva is a unique and important tissue to study immune mechanisms because it is involved in host immune response against oral biofilm that might cause periodontal diseases. Furthermore, the close proximity of the gingiva to alveolar bone tissue enables also studying bone remodeling under inflammatory conditions. Our method yields large amount of immune cells that allows analysis of even rare cell populations such as Langerhans cells and T regulatory cells as we demonstrated previously 1. Employing mice to study local immune responses involved in alveolar bone loss during periodontal diseases is advantageous because of the availability of various immunological and experimental tools. Nevertheless, due to their small size and the relatively inconvenient access to the murine gingiva, many studies avoided examination of this critical tissue. The method described in this work could facilitate gingival analysis, which hopefully will increase our understating on the oral immune system and its role during periodontal diseases.

This study describes an efficient technique to isolate and process gingival tissues from the mouse oral cavity in order to produce a single-cell culture. The resulting cells can be further used for flow cytometry analysis and molecular studies.

Isolation, traitement et analyse des cellules gingivales murins

We have developed a technique to precisely isolate and process murine gingival tissue for flow cytometry and molecular studies. The gingiva is a unique ...

Use of Shigella flexneri to Study Autophagy-Cytoskeleton Interactions

Shigella flexneri is an intracellular pathogen that can escape from phagosomes to reach the cytosol, and polymerize the host actin cytoskeleton to promote its motility and dissemination. New work has shown that proteins involved in actin-based motility are also linked to autophagy, an intracellular degradation process crucial for cell autonomous immunity. Strikingly, host cells may prevent actin-based motility of S. flexneri by compartmentalizing bacteria inside &#8216;septin cages&#8217; and targeting them to autophagy. These observations indicate that a more complete understanding of septins, a family of filamentous GTP-binding proteins, will provide new insights into the process of autophagy. This report describes protocols to monitor autophagy-cytoskeleton interactions caused by S. flexneri in vitro using tissue culture cells and in vivo using zebrafish larvae. These protocols enable investigation of intracellular mechanisms that control bacterial dissemination at the molecular, cellular, and whole organism level.

Use of Shigella flexneri to Study Autophagy-Cytoskeleton Interactions

To counteract pathogen dissemination, host cells reorganize their cytoskeleton to compartmentalize bacteria and induce autophagy. Using Shigella infection of tissue culture cells, host and pathogen determinants underlying this process are identified and characterized. Using zebrafish models of Shigella infection, the role of discovered molecules and mechanisms are investigated in vivo.

Utilisation d&#39;<em&gt; Shigella flexneri</em&gt; Pour étudier les interactions de l&#39;autophagie cytosquelette

Shigella flexneri is an intracellular pathogen that can escape from phagosomes to reach the cytosol, and polymerize the host actin cytoskeleton to promote ...

Legionella pneumophila Outer Membrane Vesicles: Isolation and Analysis of Their Pro-inflammatory Potential on Macrophages

Bacteria are able to secrete a variety of molecules via various secretory systems. Besides the secretion of molecules into the extracellular space or directly into another cell, Gram-negative bacteria can also form outer membrane vesicles (OMVs). These membrane vesicles can deliver their cargo over long distances, and the cargo is protected from degradation by proteases and nucleases. 
Legionella pneumophila (L. pneumophila) is an intracellular, Gram-negative pathogen that causes a severe form of pneumonia. In humans, it infects alveolar macrophages, where it blocks lysosomal degradation and forms a specialized replication vacuole. Moreover, L. pneumophila produces OMVs under various growth conditions. To understand the role of OMVs in the infection process of human macrophages, we set up a protocol to purify bacterial membrane vesicles from liquid culture. The method is based on differential ultracentrifugation. The enriched OMVs were subsequently analyzed with regard to their protein and lipopolysaccharide (LPS) amount and were then used for the treatment of a human monocytic cell line or murine bone marrow-derived macrophages. The pro-inflammatory responses of those cells were analyzed by enzyme-linked immunosorbent assay. Furthermore, alterations in a subsequent infection were analyzed. To this end, the bacterial replication of L. pneumophila in macrophages was studied by colony-forming unit assays. 
Here, we describe a detailed protocol for the purification of L. pneumophila OMVs from liquid culture by ultracentrifugation and for the downstream analysis of their pro-inflammatory potential on macrophages.

Legionella pneumophila Outer Membrane Vesicles: Isolation and Analysis of Their Pro-inflammatory Potential on Macrophages

Here, we describe the purification of Legionella pneumophila (L. pneumophila) outer membrane vesicles (OMVs) from liquid cultures. These purified vesicles are then used for the treatment of macrophages to analyze their pro-inflammatory potential.

Legionella pneumophila membrane externe Vésicules: Isolement et analyse de leur potentiel pro-inflammatoire sur Macrophages

Bacteria are able to secrete a variety of molecules via various secretory systems. Besides the secretion of molecules into the extracellular space or ...

Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

Salmonella typhimurium is a facultative intracellular bacterium that causes gastroenteritis in humans. After invasion of the lamina propria, S. typhimurium bacteria are quickly detected and phagocytized by macrophages, and contained in vesicles known as phagosomes in order to be degraded. Isolation of S. typhimurium-containing phagosomes have been widely used to study how S. typhimurium infection alters the process of phagosome maturation to prevent bacterial degradation. Classically, the isolation of bacteria-containing phagosomes has been performed by sucrose gradient centrifugation. However, this process is time-consuming, and requires specialized equipment and a certain degree of dexterity. Described here is a simple and quick method for the isolation of S. typhimurium-containing phagosomes from macrophages by coating the bacteria with biotin-streptavidin-conjugated magnetic beads. Phagosomes obtained by this method can be suspended in any buffer of choice, allowing the utilization of isolated phagosomes for a broad range of assays, such as protein, metabolite, and lipid analysis. In summary, this method for the isolation of S. typhimurium-containing phagosomes is specific, efficient, rapid, requires minimum equipment, and is more versatile than the classical method of isolation by sucrose gradient-ultracentrifugation.

Isolation of Salmonella typhimurium-containing Phagosomes from Macrophages

We describe here a simple and quick method for the isolation of Salmonella typhimurium-containing phagosomes from macrophages by coating the bacteria with biotin and streptavidin.

Isolement de Salmonella typhimurium-contenant des Phagosomes des Macrophages

Salmonella typhimurium is a facultative intracellular bacterium that causes gastroenteritis in humans. After invasion of the lamina propria, S. ...

Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin

Phylogenetic analysis uses nucleotide or amino acid sequences or other parameters, such as domain sequences and three-dimensional structure, to construct a tree to show the evolutionary relationship among different taxa (classification units) at the molecular level. Phylogenetic analysis can also be used to investigate domain relationships within an individual taxon, particularly for organisms that have undergone substantial change in morphology and physiology, but for which researchers lack fossil evidence due to the organisms&#39; long evolutionary history or scarcity of fossilization.
In this text, a detailed protocol is described for using the phylogenetic method, including amino acid sequence alignment using Clustal Omega, and subsequent phylogenetic tree construction using both Maximum Likelihood (ML) of Molecular Evolutionary Genetics Analysis (MEGA) and Bayesian Inference via MrBayes. To investigate the origin of eukaryotic Sugars Will Eventually be Exported Transporters (SWEET) genes, 228 SWEETs including 35 SWEET proteins from unicellular eukaryotes and 57 SemiSWEET proteins from prokaryotes were analyzed. Interestingly, SemiSWEETs were found in prokaryotes, but SWEETs were found in eukaryotes. Two phylogenetic trees constructed using theoretically distinct methods have consistently&#160;suggested that the first eukaryotic SWEET gene might stem from the fusion of a bacterial SemiSWEET gene and an archaeal SemiSWEET gene.&#160;It is worth noting that one should be cautious to draw a conclusion based only on phylogenetic analysis, although it is useful to explain the underlying relationship between different taxa, which is difficult or even impossible to discern through experimental means.

A method of constructing a phylogenetic tree based on sequence homology of SWEETs from eukaryotes and SemiSWEETs from prokaryotes is described. Phylogenetic analysis is a useful tool for explaining the evolutionary relatedness between homologous proteins or genes from different organism groups.

À l’aide de l’analyse phylogénétique pour étudier l’origine de gènes eucaryotes

Phylogenetic analysis uses nucleotide or amino acid sequences or other parameters, such as domain sequences and three-dimensional structure, to construct ...

Assessment of Antibody-based Drugs Effects on Murine Bone Marrow and Peritoneal Macrophage Activation

Macrophages are phagocytic innate immune cells, which initiate immune responses to pathogens and contribute to healing and tissue restitution. Macrophages are equally important in turning off inflammatory responses. We have shown that macrophages stimulated with intravenous immunoglobulin (IVIg) can produce high amounts of the anti-inflammatory cytokine, interleukin 10 (IL-10), and low levels of pro-inflammatory cytokines in response to bacterial lipopolysaccharides (LPS). IVIg is a polyvalent antibody, primarily immunoglobulin Gs (IgGs), pooled from the plasma of more than 1,000 blood donors. It is used to supplement antibodies in patients with immune deficiencies or to suppress immune responses in patients with autoimmune or inflammatory conditions. Infliximab, a therapeutic anti-tumor necrosis factor alpha (TNF&#945;) antibody, has also been shown to activate macrophages to produce IL-10 in response to inflammatory stimuli. IVIg and other antibody-based biologics can be tested to determine their effects on macrophage activation. This paper describes methods for derivation, stimulation, and assessment of murine bone marrow macrophages activated by antibodies in vitro and murine peritoneal macrophages activated with antibodies in vivo. Finally, we demonstrate the use of western blotting to determine the contribution of specific cell signaling pathways to anti-inflammatory macrophage activity. These protocols can be used with genetically modified mice, to determine the effect of a specific protein(s) on anti-inflammatory macrophage activation. These techniques can also be used to assess whether specific biologics may act by changing macrophages to an IL-10-producing anti-inflammatory activation state that reduces inflammatory responses in vivo. This can provide information on the role of macrophage activation in the efficacy of biologics during disease models in mice, and provide insight into a potential new mechanism of action in people. Conversely, this may caution against the use of specific antibody-based biologics to treat infectious disease, particularly if macrophages play an important role in host defense against that infection.

Antibody-based drugs have revolutionized treatment for inflammatory diseases. In addition to having direct effects on specific targets, antibodies can activate macrophages to become anti-inflammatory. This protocol describes how anti-inflammatory macrophage activation can be assessed in vitro, using mouse bone marrow macrophages, and in vivo, using peritoneal macrophages.

Évaluation des effets de médicaments à base d’anticorps murins de la moelle osseuse et d’Activation des macrophages péritonéaux

Macrophages are phagocytic innate immune cells, which initiate immune responses to pathogens and contribute to healing and tissue restitution. Macrophages ...

Isolation and In Vitro Culture of Murine and Human Alveolar Macrophages

Alveolar macrophages are terminally differentiated, lung-resident macrophages of prenatal origin. Alveolar macrophages are unique in their long life and their important role in lung development and function, as well as their lung-localized responses to infection and inflammation. To date, no unified method for identification, isolation, and handling of alveolar macrophages from humans and mice exists. Such a method is needed for studies on these important innate immune cells in various experimental settings. The method described here, which can be easily adopted by any laboratory, is a simplified approach to harvesting alveolar macrophages from bronchoalveolar lavage fluid or from lung tissue and maintaining them in vitro. Because alveolar macrophages primarily occur as adherent cells in the alveoli, the focus of this method is on dislodging them prior to harvest and identification. The lung is a highly vascularized organ, and various cell types of myeloid and lymphoid origin inhabit, interact, and are influenced by the lung microenvironment. By using the set of surface markers described here, researchers can easily and unambiguously distinguish alveolar macrophages from other leukocytes, and purify them for downstream applications. The culture method developed herein supports both human and mouse alveolar macrophages for in vitro growth, and is compatible with cellular and molecular studies.

Isolation and In Vitro Culture of Murine and Human Alveolar Macrophages

This communication describes methodologies for isolation and culture of alveolar macrophages from humans and murine models for experimental purposes.

Isolement et la Culture In Vitro de Macrophages alvéolaires murines et humaines

Alveolar macrophages are terminally differentiated, lung-resident macrophages of prenatal origin. Alveolar macrophages are unique in their long life and ...