Questo lavoro è stato sostenuto da sovvenzioni NIH AI56168, AI71142, AI87541 e AI100631 di MDP. Maurizio Del Poeta è Burroughs Wellcome Investigator in Malattie Infettive.

1. Colesterolo esaurimento delle Cellule J774A.1 con MβCD <ol><li> In un armadio biosicurezza sterili, 10 5 J774A.1 macrofagi come seme per bene su una piastra di coltura cellulare a 96 pozzetti in 200 ml di Dulbecco modificato (DMEM) supplementato con siero fetale bovino al 10% (FBS) e 1% penicillina / streptomicina (P / S). Incubare a 37 ° C e 5% CO 2 O / N. </li><li> Rimuovere i supporti dal monostrato cellulare e lavare le cellule due volte con 1x tampone fosfato salino (PBS), che è stata filtrata o in autoclave. </li><li> Aggiungere 200 ml di soluzione MβCD alla concentrazione desiderata (10 mM mM o 30 in PBS) o PBS 1x come controllo e incubare per 30 min a 37 ° C con agitazione. Rimuovere il surnatante e riserva a RT per l&#39;analisi quantitativa con kit disponibile in commercio subito dopo la procedura. </li><li> Lavare le cellule due o tre volte con PBS 1x o siero DMEM gratuito e continuare con infezione o lisi delle cellule di pipetting due o tre volte con H 2 O deionizzata per l&#39;analisi mediante cromatografia su strato sottile o con un kit. NOTA: Dopo colesterolo deplezione un kit disponibile in commercio colesterolo quantificazione può essere utilizzato. Vedere la sezione Materiali per i dettagli. Seguire le istruzioni del produttore come scritto. </li></ol> 2. Osservazione di colesterolo contenuti da cromatografia su strato sottile (TLC) <ol><li> Lavare un serbatoio TLC due volte con acetone e una volta con una soluzione di etere di petrolio: etere dietilico: acido acetico (65: 30: 1 in volume). Saturare il serbatoio con l&#39;etere di petrolio: etere dietilico: acido acetico (65: 30: 1 in volume) e lasciare soluzione O / N. NOTA: Organic solventi devono essere utilizzati sotto una cappa per evitare l&#39;inalazione di vapori. Guanti e camice da laboratorio devono essere indossati in ogni momento. L&#39;acido acetico è un acido forte e deve essere usato con cautela. </li><li> In un armadio biosicurezza sterile, seme 10 6 J774A.1 i macrofagi per bene su un ce 6-benell piastra di coltura in un volume di 5 ml di DMEM calda supplementato con 10% FBS e 1% P / S. Incubare a 37 ° C, 5% CO 2 O / N. </li><li> Esaurire macrofagi di colesterolo seguendo i passaggi 1,2-1,4, sostituendo 1 ml per 200 microlitri se del caso per tenere conto delle dimensioni ben più grandi. </li><li> Aggiungere 500 ml di tripsina-EDTA ad ogni pozzetto, incubare per 3 minuti a 37 ° C, e raschiare delicatamente le cellule con un raschietto cellulare. </li><li> Trasferire in una provetta per microcentrifuga e aggiungere ulteriori 500 ml di DMEM caldo supplementato con 10% FBS e 1% P / S. </li><li> Spin le cellule per 5 minuti a 300 xg e rimuovere il surnatante. </li><li> Aggiungere altri 500 ml di DMEM supplementato con calda 10% FBS e 1% P / S al pellet e risospendere accuratamente pipettando su e giù. </li><li> Rimuovere 10 ml di cellule e contare le cellule su un emocitometro. Normalizzare la concentrazione cellulare di ciascun campione e aggiungere un numero uguale di cellule di tubi di vetro. NOTA: A questo punto, si puòscegliere di combinare cellule dagli stessi gruppi di trattamento per ottenere un estratto lipidico finale più concentrato. </li><li> Cellule centrifugare a 300 xg per 5 minuti a temperatura ambiente e rimuovere i supporti. </li><li> Aggiungere 2 ml di metanolo e vortex. Quindi, aggiungere 1 ml di cloroformio e vortex. Controllare lo stato di fase per assicurarsi che la soluzione in monofasica. NOTA: tubi può essere conservato a 4 ° CO / N. </li><li> Centrifugare a 1700 xg per 10 minuti a RT e trasferire il surnatante in una nuova provetta </li><li> Aggiungere un ulteriore 1 ml di cloroformio seguita da 1 ml di dH 2 O. Vortex due volte per 30 sec. Centrifugare a 1700 xg per 5 minuti a temperatura ambiente. </li><li> Pesare un tubo di vetro ad una bilancia sensibile e utilizzare una pipetta Pasteur di vetro per trasferire la fase inferiore nel tubo di vetro del peso noto. </li><li> Asciugare giù lipidi in un evaporatore centrifuga fino a secco (circa 2 ore). Pesare tubo con lipidi secchi e calcolare il peso a secco di lipidi. NOTA: lipidi secco può essere memorizzato in -20 ° C fino al momento di effettuare TLC. </li><li> Diluire lipidi essiccati in cloroformio sufficiente per normalizzare la concentrazione di lipidi (di solito 20 - 50 microlitri) e 20 microlitri di carico del lipide diluito su una piastra di TLC silice. Carico 20 mg di colesterolo diluito in 20 ml di cloroformio come standard. </li><li> Aggiungere piastra TLC essiccato al serbatoio TLC saturi e consentire solvente migrare fino a 1 cm prima piastra di bordo. Rimuovere la piastra TLC dal serbatoio e lasciarlo asciugare circa 5 min. </li><li> Visualizza lipidi mettendo in un serbatoio vapori di iodio per controllare la migrazione. Rimuovere e consentono punti di dissolvenza per circa 10 - 15 minuti sotto il cofano. NOTA: Lo iodio è un pericolo per inalazione. Utilizzare sempre sotto una cappa aspirante. </li><li> Preparare una soluzione per la colorazione lipidi neutri combinando 60 ml di metanolo con 60 ml di H 2 O deionizzata, 4 ml di acido solforico, e 630 mg di cloruro di manganese. </li><li> Lentamente e con cautela immergere la piastra TLC nella soluzione lipidica colorazione neutra in un vassoio e rimuovere senza desquamazione della silice layer. NOTA: La soluzione lipidica colorazione neutra può essere riutilizzato più volte e in modo che possa essere recuperato dal vassoio e rimesso in una bottiglia per un uso successivo. </li><li> Lasciare piastra asciugare sotto il cofano a RT finché è scomparsa tutte le bolle. Riscaldare la piastra TLC su un set blocco termico a 160 ° C e char al colore desiderato. NOTA: Un programma densitometria come Vision Lavori LS può essere utilizzato per quantificare le bande carbonizzati per confrontare i campioni di lipidi. </li></ol> 3. L&#39;infezione dei macrofagi con C. neoformans (H99) <ol><li> In un armadio biosicurezza sterili, semi di 10 celle 5 macrofagi come per bene su una piastra di coltura cellulare a 96 pozzetti in 200 ml di DMEM supplementato con 10% FBS e 1% P / S. Incubare a 37 ° C, 5% CO 2, 5% CO 2 O / N. NOTA: L&#39;infezione può essere effettuata anche in fondo di vetro piatti confocale per l&#39;imaging più facile; tutti gli importi rimangono gli stessi. </li><li> Crescere una cultura di C. neoformans (H99)inoculando 10 ml di YNB con una colonia ottenuto da una piastra colpito e incubando è O / N a 30 ° C con agitazione. </li><li> Lavare e contare C. neoformans (H99), le cellule. <ol><li> Centrifuga C. cultura neoformans O / N a 1.700 xg per 10 min a 4 ° C. </li><li> Rimuovere il supporto e scartare. Lavare le cellule con 5 ml di 1x PBS. Centrifugare a 1.700 xg per 10 min a 4 ° C. </li><li> Rimuovere PBS e lavare con 5 ml di filtrato 1x PBS. Centrifugare a 1.700 xg per 10 min a 4 ° C. Ripetere questa operazione altre 2 volte. </li><li> Rimuovere PBS e risospendere in 5 ml di 1x PBS. </li><li> Fare diluizioni seriali in PBS per ottenere una diluizione 1: 500 della cultura lavato. <ol><li> Aggiungere 100 microlitri del campione originale 900 microlitri di PBS 1x per ottenere una diluizione 1:10. </li><li> Aggiungere 100 ml di 01:10 campione diluito a 900 ml di 1x PBS per ottenere una diluizione 1: 100. </li><li> Aggiungere 200 ml di 1: campione diluito 100 a 800 ml di PBS 1x per ottenere un 1: 500 dilutisu </li></ol></li><li> Prendere 10 ml di diluizione 1: 500 e contare su emocitometro per calcolare il numero di cellule. </li></ol></li><li> Preparare soluzione di lavoro per l&#39;attivazione dei macrofagi e opsonizzare C. neoformans. <ol><li> Diluire LPS e IFNγ 100x di soluzioni di riserva con l&#39;aggiunta di 10 ml a 990 ml. NOTA: LPS e IFNγ vengono utilizzati per migliorare l&#39;assorbimento dei fagociti, ma non sono necessari per la fagocitosi. Se c&#39;è un interesse per l&#39;attività fungicida dei macrofagi, effettuare l&#39;attivazione O / N a 37 ° C con agitazione prima dell&#39;infezione. </li><li> Per esempio combinano 7,5 ml di LPS diluito, 1,25 ml di IFNγ diluita, 1,25 ml di anticorpi GXM e il volume del C. cultura neoformans che dà 1,25 x 10 5 cellule. Portare il volume fino a 250 ml, moltiplicato per il numero di campioni con DMEM supplementato con 10% FBS e 1% P / S. </li><li> Vortex e incubare soluzione per 20 minuti a 37 ° C con agitazione. NOTA:Colesterolo esaurimento (i passaggi 1,2-1,4) può essere fatto in concomitanza con la fase di opsonizzazione. Assicurati di trattare macrofagi prima di combinare la soluzione di lavoro, in quanto le cellule opsonizzati devono essere utilizzati in modo ottimale non più di 20 minuti dopo la fase di incubazione 3.4.3. </li></ol></li><li> Infettare macrofagi <ol><li> Macrofagi lavare due volte con siero DMEM gratuito e aggiungere 200 ml di opsonizzati C. neoformans soluzione di lavoro di ogni bene. </li><li> Incubare per 2 ore a 37 ° C. </li></ol></li><li> Fix e colorare le cellule <ol><li> Rimuovere i supporti e lavare le cellule 2 volte con DMEM. </li><li> Far asciugare il monostrato cellulare per 10 minuti e aggiungere 200 ml di metanolo ghiaccio freddo per fissare le cellule. </li><li> Incubare per 15 minuti a RT e rimuovere il metanolo rimanente. </li><li> Aggiungere 200 ml di 10x Giemsa e incubare per 5 minuti a temperatura ambiente. </li><li> Lavare 2 - 3 volte con acqua deionizzata e asciugare O / N con cappuccio. NOTA: Imaging può essere fatto il giorno dopo o fino a una settimana following colorazione. </li></ol></li><li> Visualizza e Conte <ol><li> Utilizzando un microscopio, conta 300 cellule per punto dati (se ci sono 2 dello stesso trattamento contare 150 per bene) e annotare il numero di macrofagi infetti e il numero di cellule Cryptococcus inghiottito. NOTA: Per assicurare anche il campionamento per use punto dati 2 piastre per condizione, selezionare 3 aree non sovrapposte per piastra e conta 50 cellule per zona. </li><li> Calcolare indice phagocytic moltiplicando la percentuale di macrofagi infettati dal numero medio di C. neoformans per macrofagi. Normalizzare indice phagocytic esprimendo i valori in percentuale del 1x PBS trattati di controllo. Dopo diverse prove calcolare il valore medio e la deviazione standard della media per determinare le tendenze nell&#39;indice fagocitosi. Utilizzare studente t-test per stabilire significatività. </li><li> Prendere microscopio di cellule a 1,000X o 400X di ingrandimento. </li></ol></li></ol> 4. Trypan Blue Assay <ol><li> In un armadio biosicurezza sterile, sementi 10 6 i macrofagi per pozzetto su una piastra di coltura cellulare 6 pozzetti in un volume di 5 ml di mezzo minimo essenziale di Dulbecco (DMEM) supplementato con 10% siero bovino fetale ed 1% di penicillina / streptomicina . Incubare a 37 ° C, 5% CO 2 O / N. </li><li> Esaurire macrofagi di colesterolo seguendo i passaggi 1,2-1,4 sostituendo 2 ml per 200 microlitri se del caso per tenere conto delle dimensioni ben più grandi. NOTA: Assicurarsi di includere un controllo trattato con 1x PBS, nonché un controllo che viene raschiata prima di qualsiasi trattamento. </li><li> Aggiungere 500 ml di 1x PBS in ciascun pozzetto e raschiare delicatamente le cellule con un raschietto cellulare. Trasferire in una provetta per microcentrifuga e sospendere le cellule pipettando gentilmente su e giù. </li><li> Rimuovere 10 ml di cellule e macchia con 1 ml di 4% Trypan blu. </li><li> Contare le cellule su un emocitometro e calcolare la vitalità utilizzando la seguente equazione:% redditività = [1 - (cellule blu / cellule totali)]x 100. I valori Normalizzare al controllo che è stato non trattato. Dopo diverse prove calcolare il valore medio e la deviazione standard per determinare le tendenze in redditività. Utilizzare studente t-test per stabilire significatività. </li></ol>

<ol>
	<li>Sarantis, H., Grinstein, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subversion+of+phagocytosis+for+pathogen+survival.">Subversion of phagocytosis for pathogen survival.</a> Cell Host &amp; Microbe. 12 (4), 419-431 (2012).</li><li>Rougerie, P., Miskolci, V., Cox, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+Of+Membrane+Structures+During+Phagocytosis+And+Chemotaxis+Of+Macrophages:+Role+And+Regulation+Of+The+Actin+Cytoskeleton.">Generation Of Membrane Structures During Phagocytosis And Chemotaxis Of Macrophages: Role And Regulation Of The Actin Cytoskeleton.</a> Immunological Reviews. 256 (1), 222-239 (1111).</li><li>Liu, T., Perlin, D. S., Xue, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+Mechanisms+Of+Cryptococcal+Meningitis.">Molecular Mechanisms Of Cryptococcal Meningitis.</a> Virulence. 3, 173 (2012).</li><li>Abadi, J., Pirofski, 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+Antibodies+Reactive+With+The+Cryptococcal+Capsular+Polysaccharide+Glucuronoxylomannan+Are+Present+In+Sera+From+Children+With+And+Without+Human+Immunodeficiency+Virus+Infection.">A Antibodies Reactive With The Cryptococcal Capsular Polysaccharide Glucuronoxylomannan Are Present In Sera From Children With And Without Human Immunodeficiency Virus Infection.</a> The Journal Of Infectious Diseases. 180 (3), 915-919 (1999).</li><li>Kechichian, T. B., Shea, J., Del Poeta, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Depletion+Of+Alveolar+Macrophages+Decreases+The+Dissemination+Of+A+Glucosylceramide-Deficient+Mutant+Of+Cryptococcus+Neoformans+In+Immunodeficient+Mice.">Depletion Of Alveolar Macrophages Decreases The Dissemination Of A Glucosylceramide-Deficient Mutant Of Cryptococcus Neoformans In Immunodeficient Mice.</a> Infection And Immunity. 75 (10), 4792-4798 (2007).</li><li>Casadevall, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cryptococci+At+The+Brain+Gate:+Break+And+Enter+Or+Use+A+Trojan+Horse.">Cryptococci At The Brain Gate: Break And Enter Or Use A Trojan Horse.</a> The Journal Of Clinical Investigation. 120 (5), 1389-1692 (1172).</li><li>Chr&#233;tien, F., 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=Pathogenesis+Of+Cerebral+Cryptococcus+Neoformans+Infection+After+Fungemia.">Pathogenesis Of Cerebral Cryptococcus Neoformans Infection After Fungemia.</a> The Journal Of Infectious Diseases. 186 (4), 522-530 (2002).</li><li>Luberto, C., Martinez-Mari&#241;o, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+Of+App1+As+A+Regulator+Of+Phagocytosis+And+Virulence+Of+Cryptococcus+Neoformans.">Identification Of App1 As A Regulator Of Phagocytosis And Virulence Of Cryptococcus Neoformans.</a> The Journal Of Clinical Investigation. 112 (7), 1080-1094 (1172).</li><li>Mcquiston, T. J., Williamson, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Paradoxical+Roles+Of+Alveolar+Macrophages+In+The+Host+Response+To+Cryptococcus+Neoformans.">Paradoxical Roles Of Alveolar Macrophages In The Host Response To Cryptococcus Neoformans.</a> Journal Of Infection And Chemotherapy: Official Journal Of The Japan Society Of Chemotherapy. 18 (1), 1-9 (2012).</li><li>Garc&#237;a-Rodas, R., Zaragoza, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Catch+Me+If+You+Can:+Phagocytosis+And+Killing+Avoidance+By+Cryptococcus+Neoformans.">Catch Me If You Can: Phagocytosis And Killing Avoidance By Cryptococcus Neoformans.</a> FEMS Immunology And Medical Microbiology. 64 (2), 147-161 (2012).</li><li>Coelho, C., Bocca, A. L., Casadevall, 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+Intracellular+Life+Of+Cryptococcus+Neoformans.">The Intracellular Life Of Cryptococcus Neoformans.</a> Annual Review Of Pathology. 9. 219, 10-1146 (2014).</li><li>Rao, M., Peachman, K. K., Alving, C. R., Rothwell, S. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Depletion+Of+Cellular+Cholesterol+Interferes+With+Intracellular+Trafficking+Of+Liposome-Encapsulated+Ovalbumin.">Depletion Of Cellular Cholesterol Interferes With Intracellular Trafficking Of Liposome-Encapsulated Ovalbumin.</a> Immunology And Cell Biology. 81, 415-423 (2003).</li><li>Sein, K. K., Aikawa, 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+Prime+Role+Of+Plasma+Membrane+Cholesterol.">The Prime Role Of Plasma Membrane Cholesterol.</a> In The Pathogenesis Of Immune Evasion And Clinical Manifestations Of Falciparum Malaria. Medical Hypotheses. 51 (2), 10-1016 (1998).</li><li>Pucadyil, T. J., Tewary, P., Madhubala, R., Chattopadhyay, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cholesterol+Is+Required+For+Leishmania+Donovani+Infection:+Implications+In+Leishmaniasis.">Cholesterol Is Required For Leishmania Donovani Infection: Implications In Leishmaniasis.</a> Molecular And Biochemical Parasitology. 133, 145-152 (2004).</li><li>Tagliari, L., 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=Membrane+Microdomain+Components+Of+Histoplasma+Capsulatum+Yeast+Forms,+And+Their+Role+In.">Membrane Microdomain Components Of Histoplasma Capsulatum Yeast Forms, And Their Role In.</a> Alveolar Macrophage Infectivity. Biochimica Et Biophysica Acta. 1818 (3), 458-466 (2012).</li><li>Crane, J. M., Tamm, L. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+Of+Cholesterol+In+The+Formation+And+Nature+Of+Lipid+Rafts+In+Planar+And+Spherical+Model+Membranes.">Role Of Cholesterol In The Formation And Nature Of Lipid Rafts In Planar And Spherical Model Membranes.</a> Biophysical Journal. 86 (5), 2965-2979 (2004).</li><li>Brown, D. A., London, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functions+Of+Lipid+Rafts+In+Biological+Membranes.">Functions Of Lipid Rafts In Biological Membranes.</a> Annual Review Of Cell And Developmental Biology. 14, 111-136 (1998).</li><li>Simons, K., Toomre, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+Rafts+And+Signal+Transduction+Nature+Reviews.">Lipid Rafts And Signal Transduction Nature Reviews.</a> Molecular Cell Biology. 1 (1), 31-39 (2000).</li><li>Ilangumaran, S., Hoessli, 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=Effects+Of+Cholesterol+Depletion+By+Cyclodextrin+On+The+Sphingolipid+Microdomains+Of+The+Plasma+Membrane.">Effects Of Cholesterol Depletion By Cyclodextrin On The Sphingolipid Microdomains Of The Plasma Membrane.</a> The Biochemical Journal. 335 (Pt 2), 433-440 (1998).</li><li>Bligh, E. G., Dyer, W. 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+Rapid+Method+Of+Total+Lipid+Extraction+And+Purification).">A Rapid Method Of Total Lipid Extraction And Purification).</a> Canadian Journal Of Biochemistry And Physiology. 37 (8), 911-917 (1959).</li><li>Mukherjee, S., Lee, S., Casadevall, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibodies+To+Cryptococcus+Neoformans+Glucuronoxylomannan+Enhance+Antifungal+Activity+Of+Murine+Macrophages.">Antibodies To Cryptococcus Neoformans Glucuronoxylomannan Enhance Antifungal Activity Of Murine Macrophages.</a> Infect. Immun. 63 (2), 573-579 (1995).</li><li>Deshaw, M., Pirofski, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Antibodies+To+The+Cryptococcus+Neoformans+Capsular+Glucuronoxylomannan+Are+Ubiquitous.">Antibodies To The Cryptococcus Neoformans Capsular Glucuronoxylomannan Are Ubiquitous.</a> In Serum From HIV+ And HIV- Individuals. Clinical And Experimental Immunology. 99 (3), 425-432 (1995).</li><li>Tripathi, K., Mor, V., Bairwa, N. K., Del Poeta, M., Mohanty, B. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydroxyurea+Treatment+Inhibits+Proliferation+Of+Cryptococcus+Neoformans+In+Mice.">Hydroxyurea Treatment Inhibits Proliferation Of Cryptococcus Neoformans In Mice.</a> Frontiers In Microbiology. 3, 187 (2012).</li><li>Chaka, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantitative+Analysis+Of+Phagocytosis+And+Killing+Of+Cryptococcus+Neoformans+By+Human+Peripheral+Blood+Mononuclear+Cells+By+Flow+Cytometry.">Quantitative Analysis Of Phagocytosis And Killing Of Cryptococcus Neoformans By Human Peripheral Blood Mononuclear Cells By Flow Cytometry.</a> Clin. Diagn. Lab. Immunol. 2 (6), 753-759 (1995).</li></ol>

The authors have nothing to disclose.

Lavorando con questo protocollo è importante per ottenere il conteggio delle cellule accurate quando placcatura cellule di mammifero e opsonizzare C. cellule neoformans. Questo minimizza variazione tra prove e assicura un&#39;accurata 1: 1 bersaglio rapporto effettore tutto lo studio. È anche fondamentale per coordinare la tempistica della deplezione di colesterolo e per prevenire l&#39;infezione delle cellule di lievito o cellule opsonizzati macrofagi trattati di riposo a RT tra le procedure. Lunghi...

Fagocitosi è un processo attraverso il quale entita extracellulari vengono internalizzati dalle cellule ospiti. Si tratta di un&#39;arma fondamentale nell&#39;arsenale del sistema immunitario a difendersi contro gli agenti patogeni, ma il processo può spesso essere sovvertita da agenti patogeni per consentire l&#39;internalizzazione e la diffusione in tutto il corpo 1. Fagocitosi è mediata da diversi eventi di segnalazione che si traducono in attacco e fagocitazione via riarrangiamenti del citoscheletro della cellula ospite. Fagociti &#39;professionali&#39; sono in grado di riconoscere e legarsi a opsonine sulla superficie del patogeno invasore di segnalare per l&#39;attacco e la formazione di lamellipodia, che fagocitare l&#39;agente patogeno e formano un phagosome 2. Tra i cosiddetti fagociti &#39;professionali&#39; sono i macrofagi. I macrofagi sono cellule altamente specializzate che svolgono funzioni di protezione che includono ricercare e eliminare gli agenti patogeni, riparare tessuti danneggiati, e mediare l&#39;infiammazione, la maggior parte deiquesti attraverso il processo di fagocitosi 1,2. Cryptococcus neoformans è una specie di lievito patogeno che provoca una grave malattia nota come Criptococcosi. Spore Cryptococcus inalazione dall&#39;host e determinano un&#39;infezione polmonare che di solito è asintomatica. Si ritiene che l&#39;esposizione è estremamente diffuso; un campione di 61 bambini dalle malattie infettive Pediatric Clinic presso il Centro Ospedaliero Bronx-Lebanon trovato che tutti gli intervistati avevano anticorpi al glucuronoxylomannan polisaccaride criptococcica e altri studi hanno dimostrato la prevalenza sia il virus dell&#39;immunodeficienza umana (HIV) non infetto e adulti infetti 3, 4. macrofagi alveolari sono la prima linea di risposta all&#39;infezione polmonare e in molti casi con successo chiaro patogeno. Tuttavia, in soggetti immunocompromessi (pazienti ad esempio, HIV e AIDS), il lievito è in grado di sopravvivere all&#39;interno dei macrofagi. In questicasi, i macrofagi possono servire come una nicchia per la replicazione del patogeno e possono facilitare la sua diffusione al sistema nervoso centrale (CNS) se la malattia diventa fatale 5 - 8. Si pensa che i macrofagi possono anche consegnare il lievito direttamente nelle meningi, aiutando il lievito di attraversare la barriera emato-encefalica tramite il modello &quot;cavallo di Troia&quot; 3,9 - 11. Pertanto, è importante comprendere il processo di fagocitosi ed i fattori che incidono su di esso, specialmente nelle infezioni da criptococco. Impieghi precedenti in altri sistemi patogeni puntare colesterolo e lipidi zattere formate da colesterolo come aventi un ruolo importante da svolgere in fagocitosi 12-15. Il colesterolo è la specie di lipidi più abbondante in cellule di mammifero e comprende 25 - 50% della membrana cellulare di mammifero 16. Si è trovato un ruolo nella modulazione della BIOPproprietà hysical di membrane di cambiare la loro rigidità 17. Colesterolo e sfingolipidi insieme formano microdomini lipidici all&#39;interno della membrana nota come zattere lipidiche. Raft lipidici sono stati trovati ad essere coinvolti nella formazione di caveolae, oltre a fornire un dominio isolato per alcuni tipi di segnalazione 16 - 18. A causa delle loro piccole dimensioni, è difficile studiare zattere lipidiche in vivo. Un modo utile per studiare il ruolo dei raft lipidici è quella di modificare i loro elettori. Metil-β-ciclodestrina (MβCD) è un composto che è stato trovato per esaurire il colesterolo dalle membrane mammiferi ed è comunemente utilizzato per studiare il ruolo dei raft lipidici 18. In questo protocollo, presentiamo un metodo per esaurire il colesterolo dalle membrane della cellula ospite e quantificare l&#39;effetto della deplezione sulla capacità delle cellule ospiti di fagocitare C. neoformans in vitro. Questo procedimento si avvale di coltura cellulare techniqUES su un macrofago immortalato come linea cellulare (J774A.1) come modello di infezione. Colesterolo deplezione stato compiuto mediante esposizione a MβCD, che ha un core idrofobico specifica alla dimensione di steroli ed è in grado di agire come un dissipatore per il colesterolo per disegnare fuori della membrana 19. Colesterolo esaurimento è stata misurata quantitativamente usando un kit disponibile in commercio e qualitativamente con una estrazione del grasso Bligh-Dyer modificato seguita da cromatografia su strato sottile (TLC) 20. . Fagocitosi è stata misurata infettando la linea cellulare con una cultura di lievito opsonizzati mescolato con un cocktail di interferone-γ e lipopolysaccharide per l&#39;attivazione dei macrofagi Cryptococcus stata opsonizzati utilizzando un anticorpo glucuronoxylomannan (GXM) 21 - 23. Colorazione e esperimenti di microscopia consentito per la visualizzazione delle cellule e calcolo dell&#39;indice fagocitaria per valutare il grado di fagocitosi. Nel loro insieme, questo protocollo dEscribes un metodo di base che integra l&#39;alterazione della composizione lipidica con un processo fisiologico.

<table border="0" cellpadding="0" cellspacing="0" width="622">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Name of Reagent/ Equipment</td>
			<td style="width:120px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Class II type A2 Biosafety Cabinet</td>
			<td style="width:120px;">Labconco</td>
			<td style="width:119px;">3460009</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">J774A.1 cell line</td>
			<td style="width:120px;">ATCC</td>
			<td style="width:119px;">TIB-67</td>
			<td style="width:167px;">Arrives Frozen. See ATCC instructions for culturing.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Dulbecco&#8217;s Modified Eagle Medium</td>
			<td style="width:120px;">Gibco</td>
			<td style="width:119px;">11995-065</td>
			<td style="width:167px;">Store at 4 &#176;C and warm to 37 &#176;C prior to use</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">HI Fetal Bovine Serum Performance Plus</td>
			<td style="width:120px;">Gibco</td>
			<td style="width:119px;">10082-147</td>
			<td style="width:167px;">Keep frozen at -20 &#176;C and thaw before adding to DMEM</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Penicillin-Streptomycin (10,000 U/mL)</td>
			<td style="width:120px;">Gibco</td>
			<td style="width:119px;">15140-122</td>
			<td style="width:167px;">Used to suplement DMEM</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Isotemp Cell culture incubator</td>
			<td style="width:120px;">Fisher Scientific</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Model # 3530</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">96-Well culture dish</td>
			<td style="width:120px;">Corning Inc. Costar</td>
			<td style="width:119px;">3595</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">10x Phosphate Buffered Saline</td>
			<td style="width:120px;">Fisher Scientific BioReagents</td>
			<td style="width:119px;">BP3994</td>
			<td style="width:167px;">Dilute to 1x and filter or autoclave prior to use.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Methyl-&#946;-Cyclodextrin</td>
			<td style="width:120px;">Sigma Life Science</td>
			<td style="width:119px;">C4555-10G</td>
			<td style="width:167px;">Dissolve in 1x PBS to make solutions of 10mM and 30mM concentrations</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Orbital Shaker</td>
			<td style="width:120px;">Labline</td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">Amplex Red Cholesterol Assay Kit</td>
			<td style="width:120px;">Life Technologies Molecular Probes</td>
			<td style="width:119px;">A12216</td>
			<td style="width:167px;">All reagents for Cholesterol Assay are contained within the kit. Follow Manufacturer instructions.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">96-Well Black Assay plate</td>
			<td style="width:120px;">Corning Inc. Costar</td>
			<td style="width:119px;">3603</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">FilterMax microplate reader</td>
			<td style="width:120px;">Molecular Devices</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Model F5</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">TLC Chamber</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">Z126195-1EA</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Chloroform</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">650498-4L</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Methanol</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">34860-2L-R</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">TLC Paper</td>
			<td style="width:120px;">Whatman</td>
			<td style="width:119px;">3030917</td>
			<td style="width:167px;">Cut down to size needed for TLC tank</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Fume Hood</td>
			<td style="width:120px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Any fume hood that complies with AIHA/ANSI Standards&#160;</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">6-Well Plate</td>
			<td style="width:120px;">Corning Inc. Costar</td>
			<td style="width:119px;">3506</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Trypsin-EDTA</td>
			<td style="width:120px;">Gibco</td>
			<td style="width:119px;">25300-054</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cell Scraper</td>
			<td style="width:120px;">Corning Inc. Costar</td>
			<td style="width:119px;">3010</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Hemocytometer&#160;</td>
			<td style="width:120px;">Hausser Scientific</td>
			<td style="width:119px;">1490</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Centrifuge</td>
			<td style="width:120px;">Beckman Coulter</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Model Alegra x-30R</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Votex Mixer</td>
			<td style="width:120px;">Fisher Scientific</td>
			<td style="width:119px;">12-812</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Balance</td>
			<td style="width:120px;">Mettler Toledo</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Model # MS104S Meaures down to .1 mg</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glass Pasteur Pipette</td>
			<td style="width:120px;">Fisherbrand</td>
			<td style="width:119px;">13-678-20A</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cholesterol</td>
			<td style="width:120px;">Avanti Polar Lipids</td>
			<td style="width:119px;">700000</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">SpeedVac Concentrator</td>
			<td style="width:120px;">Thermo Scientific</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Model # SPD2010&#160;</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Petroleum Ether</td>
			<td style="width:120px;">Fisher Scientific</td>
			<td style="width:119px;">E139-1&#160;</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Diethyl Ether</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">309966&#160;</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Acetic Acid</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">320099</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">TLC Silica Gel 60 with concentrating zone</td>
			<td style="width:120px;">Analytical Chromatograhy Millipore</td>
			<td style="width:119px;">1.11845.0001</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Iodine Chips</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">376558-50G</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sulfuric Acid</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">320501&#160;</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Manganese Chloride</td>
			<td style="width:120px;">Sigma-Aldrich</td>
			<td style="width:119px;">244589</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">UVP EC3 Imaging System</td>
			<td style="width:120px;">Ultra-Violet Products Ltd.</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Use the Vision Works LS software for densitometry analysis</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glass Bottom Confocal Dish</td>
			<td style="width:120px;">MatTek</td>
			<td style="width:119px;">P35G-1.5-10C</td>
			<td>www.glassbottomdishes.com</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Cryptococcus neoformans (H99)</td>
			<td style="width:120px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Obtained from Duke University Medical Center</td>
		</tr>
		<tr height="105">
			<td height="105" style="height:105px;width:216px;">YNB</td>
			<td style="width:120px;">BD</td>
			<td style="width:119px;">239210</td>
			<td style="width:167px;">See manufacturer for preparation instructions. Use a Glucose concentration of 20 g/L.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Lipopolysaccharide</td>
			<td style="width:120px;">Sigma</td>
			<td style="width:119px;">L4391-1MG</td>
			<td style="width:167px;">Dissolve in 1x PBS to make 1mg/mL stock. Store at -20 &#176;C.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Interferon gamma</td>
			<td style="width:120px;">Sigma</td>
			<td style="width:119px;">I4777</td>
			<td style="width:167px;">Dissolve in 1x PBS to make .1 mg/mL stock solution</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Glucuronoxylomannan antibody (anti-GXM)</td>
			<td style="width:120px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Gift from Arturo Casadevall&#39;s Lab concentration is 1.98 mg/mL</td>
		</tr>
		<tr height="168">
			<td height="168" style="height:168px;width:216px;">Giemsa</td>
			<td style="width:120px;">MP Biomedicals</td>
			<td style="width:119px;">194591</td>
			<td style="width:167px;">Dissolve .8 g of Giemsa in 25 mL of Glycerol and heat to 60 &#176;C for 1 hour. Add 25 mL of methanol to the solution and allow to age at room temperature for at least 1 month.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Microscope</td>
			<td style="width:120px;">Zeiss</td>
			<td style="width:119px;"></td>
			<td style="width:167px;">Observer.D1 microscope with AxioCam MRm for taking images</td>
		</tr>
	</tbody>
</table>

macrophage cholesterol depletion and its effect on the phagocytosis of cryptococcus neoformans

Criptococcosi è un&#39;infezione pericolosa per la vita causata da funghi patogeni del genere Cryptococcus. L&#39;infezione si verifica su inalazione di spore, che sono in grado di replicare nel polmone profondo. Fagocitosi di Cryptococcus dai macrofagi è uno dei modi in cui la malattia è in grado di diffondere nel sistema nervoso centrale per causare meningoencefalite letale. Pertanto, lo studio dell&#39;associazione tra Cryptococcus e macrofagi è importante per comprendere la progressione dell&#39;infezione. Il presente studio descrive un protocollo step-by-step per studiare macrofagi infettività da C. neoformans in vitro. Usando questo protocollo, il ruolo di steroli ospitanti sulle interazioni ospite-patogeno è studiato. Diverse concentrazioni di metile - ciclodestrina (MCD) sono stati usati per esaurire il colesterolo dal murino reticolo sarcoma macrofago-come linea cellulare J774A.1. Colesterolo esaurimento è stato confermato e quantificato utilizzando sia commercialmente available kit di colesterolo quantificazione e cromatografia su strato sottile. Cellule colesterolo impoverito sono stati attivati ​​mediante Lipopolysacharide (LPS) e interferone gamma (IFNγ) e infettati con anticorpi opsonizzati Cryptococcus neoformans wild-type cellule H99 ad un rapporto effettore-to-target di 1: 1. Le cellule infette sono stati monitorati dopo 2 ore di incubazione con C. neoformans e il loro indice di fagocitosi è stato calcolato. Colesterolo deplezione determinato una significativa riduzione dell&#39;indice fagocitaria. I protocolli presentati offrono un metodo conveniente per imitare l&#39;avvio del processo di infezione in un ambiente di laboratorio e studiare il ruolo della composizione lipidica host infettività.

Colesterolo Depletion Analisi del surnatante riservato al punto 1.3 del protocollo, seguendo le istruzioni del produttore del kit Colesterolo Assay Amplex Red produce un&#39;elevata concentrazione di colesterolo nel campione MβCD trattati rispetto al controllo 1x PBS. A seconda del tipo di cellula e l&#39;esaurimento colesterolo concentrazione MβCD utilizzato può variare. Per J774 trattati con MβCD 10 mM, è stato osservato un esaurimento di circa il 50%. Depletion può essere calcolato uti...

Watch this Scientific Journal Video about Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans at JoVE.com

Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans

In this article, a protocol for infection of macrophages with Cryptococcus neoformans is described. Also, a method for sterol depletion from the macrophages is explained. These protocols provide a guide to study fungal infections in vitro and examine the role of sterols in such infections.

Macrofagi Colesterolo Depletion e il suo effetto sulla fagocitosi di<em&gt; Cryptococcus neoformans</em

Cryptococcosis is a life-threatening infection caused by pathogenic fungi of the genus Cryptococcus. Infection occurs upon inhalation of spores, which are ...

macrophage-cholesterol-depletion-its-effect-on-phagocytosis

Research

JoVE Journal

Immunology and Infection

Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans

12.6K Views.  Stony Brook University. In this article, a protocol for infection of macrophages with Cryptococcus neoformans is described. Also, a method for sterol depletion from the macrophages is explained. These protocols provide a guide to study fungal infections in vitro and examine the role of sterols in such infections. 

Video: Macrophage Cholesterol Depletion and Its Effect on the Phagocytosis of Cryptococcus neoformans

Depletion of Specific Cell Populations by Complement Depletion

The purification of immune cell populations is often required in order to study their unique functions. In particular, molecular approaches such as real-time PCR and microarray analysis require the isolation of cell populations with high purity. Commonly used purification strategies include fluorescent activated cell sorting (FACS), magnetic bead separation and complement depletion. Of the three strategies, complement depletion offers the advantages of being fast, inexpensive, gentle on the cells and a high cell yield. The complement system is composed of a large number of plasma proteins that when activated initiate a proteolytic cascade culminating in the formation of a membrane-attack complex that forms a pore on a cell surface resulting in cell death1. The classical pathway is activated by IgM and IgG antibodies and was first described as a mechanism for killing bacteria. With the generation of monoclonal antibodies (mAb), the complement cascade can be used to lyse any cell population in an antigen-specific manner. Depletion of cells by the complement cascade is achieved by the addition of complement fixing antigen-specific antibodies and rabbit complement to the starting cell population. The cells are incubated for one hour at 37&deg;C and the lysed cells are subsequently removed by two rounds of washing. MAb with a high efficiency for complement fixation typically deplete 95-100% of the targeted cell population. Depending on the purification strategy for the targeted cell population, complement depletion can be used for cell purification or for the enrichment of cell populations that then can be further purified by a subsequent method.

To effectively study the function of immune cell populations their purification is often required. Complement depletion is a fast and inexpensive technique for the isolation of immune cell populations with high purity.

L&#39;esaurimento delle popolazioni di cellule specifiche da deplezione del complemento

The purification of immune cell populations is often required in order to study their unique functions.  In particular, molecular approaches such as ...

Ricerca

Immunologia e infezioni

Depletion and Reconstitution of Macrophages in Mice

Macrophages are critical players in the innate immune response to infectious challenge or injury, initiating the innate immune response and directing the acquired immune response. Macrophage dysfunction can lead to an inability to mount an appropriate immune response and as such, has been implicated in many disease processes, including inflammatory bowel diseases. Macrophages display polarized phenotypes that are broadly divided into two categories. Classically activated macrophages, activated by stimulation with IFN&gamma; or LPS, play an essential role in response to bacterial challenge whereas alternatively activated macrophages, activated by IL-4 or IL-13, participate in debris scavenging and tissue remodeling and have been implicated in the resolution phase of inflammation. During an inflammatory response in vivo, macrophages are found amid a complex mixture of infiltrating immune cells and may participate by exacerbating or resolving inflammation. To define the role of macrophages in situ in a whole animal model, it is necessary to examine the effect of depleting macrophages from the complex environment. To ask questions about the role of macrophage phenotype in situ, phenotypically defined polarized macrophages can be derived ex vivo, from bone marrow aspirates and added back to mice, with or without prior depletion of macrophages. In the protocol presented here clodronate-containing liposomes, versus PBS injected controls, were used to deplete colonic macrophages during dextran sodium sulfate (DSS)-induced colitis in mice. In addition, polarized macrophages were derived ex vivo and transferred to mice by intravenous injection. A caveat to this approach is that clodronate-containing liposomes deplete all professional phagocytes, including both dendritic cells and macrophages so to ensure the effect observed by depletion is macrophage-specific, reconstitution of phenotype by adoptive transfer of macrophages is necessary. Systemic macrophage depletion in mice can also be achieved by backcrossing mice onto a CD11b-DTR background, which is an excellent complementary approach. The advantage of clodronate-containing liposome-mediated depletion is that it does not require the time and expense involved in backcrossing mice and it can be used in mice regardless of the background of the mice (C57BL/6, BALB/c, or mixed background).

Macrophages play a central role in homeostasis and pathology in many tissues. The protocol presented here describes methods for depleting macrophages in vivo, deriving polarized macrophages from bone marrow aspirates, and adoptively transferring macrophages into mice. These techniques allow determination of the role that polarized macrophages play in health and disease.

Esaurimento e Ricostituzione dei macrofagi nei topi

Macrophages are critical players in the innate  immune response to infectious challenge or injury, initiating the innate immune  response and directing ...

The Synergistic Effect of Visible Light and Gentamycin on Pseudomona aeruginosa Microorganisms

Recently there were several publications on the bactericidal effect of visible light, most of them claiming that blue part of the spectrum (400 nm-500 nm) is responsible for killing various pathogens1-5. The phototoxic effect of blue light was suggested to be a result of light-induced reactive oxygen species (ROS) formation by endogenous bacterial photosensitizers which mostly absorb light in the blue region4,6,7. There are also reports of biocidal effect of red and near infra red8 as well as green light9.
In the present study, we developed a method that allowed us to characterize the effect of high power green (wavelength of 532 nm) continuous (CW) and pulsed Q-switched (Q-S) light on Pseudomonas aeruginosa. Using this method we also studied the effect of green light combined with antibiotic treatment (gentamycin) on the bacteria viability. P. aeruginosa is a common noscomial opportunistic pathogen causing various diseases. The strain is fairly resistant to various antibiotics and contains many predicted AcrB/Mex-type RND multidrug efflux systems10.
The method utilized free-living stationary phase Gram-negative bacteria (P. aeruginosa strain PAO1), grown in Luria Broth (LB) medium exposed to Q-switched and/or CW lasers with and without the addition of the antibiotic gentamycin. Cell viability was determined at different time points. The obtained results showed that laser treatment alone did not reduce cell viability compared to untreated control and that gentamycin treatment alone only resulted in a 0.5 log reduction in the viable count for P. aeruginosa. The combined laser and gentamycin treatment, however, resulted in a synergistic effect and the viability of P. aeruginosa was reduced by 8 log's.
The proposed method can further be implemented via the development of catheter like device capable of injecting an antibiotic solution into the infected organ while simultaneously illuminating the area with light.

The Synergistic Effect of Visible Light and Gentamycin on Pseudomona aeruginosa Microorganisms

We show that a developed biomedical device involving continuous or pulsed visible laser based treatment that is combined with antibiotic treatment (gentamycin), results in a statistically significant synergistic effect leading to a reduction in the viability of P. aeruginosa PAO1, by 8 log's compared to antibiotic treatment alone.

L&#39;effetto sinergico di luce visibile e Gentamicina su<em&gt; Pseudomonas aeruginosa</em&gt; Microrganismi

Recently there were several publications on the  bactericidal effect of visible light, most of them claiming that blue part of  the spectrum (400 nm-500 ...

Using Click Chemistry to Measure the Effect of Viral Infection on Host-Cell RNA Synthesis

Many RNA viruses have evolved the ability to inhibit host cell transcription as a means to circumvent cellular defenses. For the study of these viruses, it is therefore important to have a quick and reliable way of measuring transcriptional activity in infected cells. Traditionally, transcription has been measured either by incorporation of radioactive nucleosides such as 3H-uridine followed by detection via autoradiography or scintillation counting, or incorporation of halogenated uridine analogs such as 5-bromouridine (BrU) followed by detection via immunostaining. The use of radioactive isotopes, however, requires specialized equipment and is not feasible in a number of laboratory settings, while the detection of BrU can be cumbersome and may suffer from low sensitivity.
The recently developed click chemistry, which involves a copper-catalyzed triazole formation from an azide and an alkyne, now provides a rapid and highly sensitive alternative to these two methods. Click chemistry is a two step process in which nascent RNA is first labeled by incorporation of the uridine analog 5-ethynyluridine (EU), followed by detection of the label with a fluorescent azide. These azides are available as several different fluorophores, allowing for a wide range of options for visualization.
This protocol describes a method to measure transcriptional suppression in cells infected with the Rift Valley fever virus (RVFV) strain MP-12 using click chemistry. Concurrently, expression of viral proteins in these cells is determined by classical intracellular immunostaining. Steps 1 through 4 detail a method to visualize transcriptional suppression via fluorescence microscopy, while steps 5 through 8 detail a method to quantify transcriptional suppression via flow cytometry. This protocol is easily adaptable for use with other viruses.

This method describes the use of click chemistry to measure changes in host cell transcription after infection with the Rift Valley fever virus (RVFV) strain MP-12. Results can be visualized qualitatively via fluorescence microscopy or obtained quantitatively through flow cytometry. This method is adaptable for use with other viruses.

Utilizzando Clicca Chimica per misurare l&#39;effetto dell&#39;infezione virale sulla cellula ospite RNA Sintesi

Many RNA viruses have evolved the ability to inhibit host cell transcription as a means to circumvent cellular defenses. For the study of these viruses, ...

Visualizing Non-lytic Exocytosis of Cryptococcus neoformans from Macrophages Using Digital Light Microscopy

Many aspects of the infection of macrophages by Cryptococcus neoformans have been extensively studied and well defined. However, one particular interaction that is not clearly understood is non-lytic exocytosis. In this process, yeast cells are released into the extracellular space by a poorly understood mechanism that leaves both the macrophage and Cn viable. Here, we describe how to follow a large number of individually infected macrophages for a 24 hr infection period by time-lapsed microscopy. Infected macrophages are housed in a heating chamber with a CO2 atmosphere attached to a microscope that provides the same conditions as a cell-culture incubator. Live digital microscopy can provide information about the dynamic interactions between a host and pathogen that is not available from static images. Being able to visualize each infected cell can provide clues as to how macrophages handle fungal infections, and vice versa. This technique is a powerful tool in studying the dynamics that are behind a complex phenomenon.

Visualizing Non-lytic Exocytosis of Cryptococcus neoformans from Macrophages Using Digital Light Microscopy

We describe how to visualize macrophage-C. neoformans (Cn) interactions in real time, with specific emphasis on the process of non-lytic exocytosis using digital light microscopy. Using this technique individually infected macrophages can be studied to ascertain various aspects of this phenomenon.

Visualizzazione non-litica Esocitosi di<em&gt; Cryptococcus neoformans</em&gt; Dai macrofagi utilizzando la luce Microscopia Digitale

Many aspects of the infection of macrophages by Cryptococcus neoformans have been extensively studied and well defined. However, one particular ...

High Throughput Fluorometric Technique for Assessment of Macrophage Phagocytosis and Actin Polymerization

The goal of fluorometric analysis is to serve as an efficient, cost effective, high throughput method of analyzing phagocytosis and other cellular processes. This technique can be used on a variety of cell types, both adherent and non-adherent, to examine a variety of cellular properties. When studying phagocytosis, fluorometric technique utilizes phagocytic cell types such as macrophages, and fluorescently labeled opsonized particles whose fluorescence can be extinguished in the presence of trypan blue. Following plating of adherent macrophages in 96-well plates, fluorescent particles (green or red) are administered and cells are allowed to phagocytose for varied amounts of time. Following internalization of fluorescent particles, cells are washed with trypan blue, which facilitates extinction of fluorescent signal from bacteria which are not internalized, or are merely adhering to the cell surface. Following the trypan wash, cells are washed with PBS, fixed, and stained with DAPI (nuclear blue fluorescent label), which serves to label nuclei of cells. By a simple fluorometric quantification through plate reading of nuclear (blue) or particle (red/green) fluorescence we can examine the ratio of relative fluorescence units of green:blue and determine a phagocytic index indicative of amount of fluorescent bacteria internalized per cell. The duration of assay using a 96-well method and multichannel pipettes for washing, from end of phagocytosis to end of data acquisition, is less than 45 min. Flow cytometry could be used in a similar manner but the advantage of fluorometry is its high throughput, rapid method of assessment with minimal manipulation of samples and quick quantification of fluorescent intensity per cell. Similar strategies can be applied to non adherent cells, live labeled bacteria, actin polymerization, and essentially any process utilizing fluorescence. Therefore, fluorometry is a promising method for its low cost, high throughput capabilities in the study of cellular processes.

Here we present a protocol to quantify phagocytosis of fluorescent particles by adherent macrophage cell line using a fluorometric method. This method facilitates a high throughput quantification of particle internalization as well as the resulting actin polymerization.

Alta Tecnica Throughput fluorometrica per la valutazione dei macrofagi fagocitosi e polimerizzazione

The goal of fluorometric analysis is to serve as an efficient, cost effective, high throughput method of analyzing phagocytosis and other cellular ...

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

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

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

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

Trasformazione Biolistic di una fluorescente Tagged Gene nel Opportunistic Fungal patogeni<em&gt; Cryptococcus neoformans</em

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

RNA Purification from Intracellularly Grown Listeria monocytogenes in Macrophage Cells

Analysis of the transcriptome of bacterial pathogens during mammalian infection is a valuable tool for studying genes and factors that mediate infection. However, isolating bacterial RNA from infected cells or tissues is a challenging task, since mammalian RNA mostly dominates the lysates of infected cells. Here we describe an optimized method for RNA isolation of Listeria monocytogenes bacteria growing within bone marrow derived macrophage cells. Upon infection, cells are mildly lysed and rapidly filtered to discard most of the host proteins and RNA, while retaining intact bacteria. Next, bacterial RNA is isolated using hot phenol-SDS extraction followed by DNase treatment. The extracted RNA is suitable for gene transcription analysis by multiple techniques. This method is successfully employed in our studies of Listeria monocytogenes gene regulation during infection of macrophage cells 1-4. The protocol can be easily modified to study other bacterial pathogens and cell types.

RNA Purification from Intracellularly Grown Listeria monocytogenes in Macrophage Cells

Here we describe a method for bacterial RNA isolation from Listeria monocytogenes bacteria growing inside murine macrophages. This technique can be used with other intracellular pathogens and mammalian host cells.

RNA Purificazione da nella cellula Grown<em&gt; Listeria monocytogenes</em&gt; In macrofagi

Analysis of the transcriptome of bacterial pathogens during mammalian infection is a valuable tool for studying genes and factors that mediate infection. ...

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.

Valutazione degli effetti di farmaci a base di anticorpi sul midollo osseo murino e l'attivazione dei macrofagi peritoneali

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

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

The polysaccharide capsule of Cryptococcus neoformans is the primary virulence factor and one of the most commonly studied aspects of this pathogenic yeast. Capsule size can vary widely between strains, has the ability to grow rapidly when introduced to stressful or low nutrient conditions, and has been positively correlated with strain virulence. For these reasons, the size of the capsule is of great interest to C. neoformans researchers. The growth of the C. neoformans capsule is induced during phenotypic testing to help understand the effects of different treatments on the yeast or size differences between strains. Here we describe one of the standard methods of capsule induction and compare two accepted methods of staining and measuring capsule diameter: (i) India ink, a negative stain, used in conjunction with conventional light microscopy and (ii) co-staining with fluorescent dyes of both the cell wall and capsule followed by confocal microscopy. Finally, we show how measurement of capsule diameter from India ink-stained samples can be automated using computational image analysis.

Size Matters: Measurement of Capsule Diameter in Cryptococcus neoformans

The polysaccharide capsule is the primary virulence factor in Cryptococcus neoformans, and its size correlates with strain virulence. Capsule diameter measurements are used in phenotypic testing and to gauge therapeutic efficacy. Here a standard method of capsule induction is presented, and two methods of staining and measuring diameter are compared.

Size Matters: Misurare il diametro di capsula in Cryptococcus neoformans

The polysaccharide capsule of Cryptococcus neoformans is the primary virulence factor and one of the most commonly studied aspects of this pathogenic ...