Biz hibe T32 AI055402 (JK), R21 AI088059 (JB), ve P20RR021905 aracılığıyla bu çalışmaların destek için yararlı tartışmalar ve Ulusal Sağlık Enstitüleri (JB) için Markus Thali, Nathan Roy, Christopher Ziegler, Emily Bruce ve Benjamin Kral teşekkür .

Not: açıklanan protokol (pre-PCR laboratuvarı ve ne kadar iyi öncesi PCR tekniği kullanılarak deneyler kurmak için nasıl mükemmel bir bakış için 28 bakınız) sıkı öncesi PCR tekniği kullanılarak yapılmalıdır önemlidir. Tüm reaktifler ve ekipmanlar qPCR hedef sekansı içeren amplifiye DNA içermeyen ve uygun kontrol gibi kirlenmesini tespit etmek için bir yerde olması önemlidir. Protokolünün bir genel görünüşü Şekil 1&#39;de gösterilmiştir. 1. 48-iyi Tabaklar Medya ve Tohum Hücreler hazırlayın <ol><li> 50 ml ilave etmek suretiyle,% 10 fetal sığır serumu,% 1 penisilin-streptomisin içeren tam Dulbecco Modifiye Eagle Ortamı içinde 500 ml (DMEM), ve% 1 HEPES (N-2-hidroksi-N-2-etan sülfonik asit) tampon çözeltisi hazırlayın Isı ile inaktive edilmiş fetal büyükbaş hayvan serumu ve 5 ml DMEM 500 ml&#39;lik bir şişe için 100x penisilin-streptomisin ve 100X HEPES tampon çözeltisi, her bir. Bu reaktif 4 ° C&#39;de saklanabilir76; ay bekletilmiştir. </li><li> Tam DMEM 500 ul nihai hacimde 48 oyuklu doku kültür plakasına oyuk başına tohum 2.5 x 10 4 Vero E6 hücreleri. 10 ila 18 saat boyunca% 5 CO2 içeren nemli bir inkübatör içinde 37 ° C&#39;de inkübe plakası. <ol><li> gün sonunda plaka Tohum. ya çoğaltmak veya üç kuyularda her virüs örneği test edin. Not: Bu deney için, 48-çukurlu tabanlı bir platform tarif edilmiş olmakla birlikte, 96 veya 384 oyuklu plakalarda aşağı kullanılır tahlili büyütülebilir mümkün olmalıdır. </li></ol></li></ol> 2. Virüs-hücre Ek Yürüten Not: Bu protokolde kullanılan virüs JUNV soyu, makaleler, 1. (Cı # 1), başarılı bir şekilde JUNV hastalığının 29 önlenmesi için bir canlı zayıflatılmış bir aşı olarak kullanılmaktadır. JUNV Cı 1. in vivo ve in vitro olarak, her iki seri geçiş ile virülan JUNV streyn XJ türetilen 12 amino asit 30 ebeveyn XJ suşundan farklı edildi. because JUNV C # 1 biyogüvenlik düzeyi (BSL) -2-puan patojendir, bu bölüm için açıklanan çalışma, uygun BSL-2 uygulamaları 31 kullanılarak yapılmalıdır. Bu kişisel koruyucu ekipman (örneğin, göz koruma, laboratuvar mont, çift eldiven), bir sınıf II biyogüvenlik kabini kullanımını içerir ve tüm personelin kurumsal eğitim ve güvenle bu organizmayı işlemek için gerekli onayları aldık sağlamak. <ol><li> İstenen pfus test edilecek JUNV C # 1 örnek (ler) seyreltin veya buz gibi soğuk komple DMEM oluşturan birimler odak ve her kuyuya eklemek için hazır olana kadar buz üzerinde saklayın. Not: Tüm DMEM içinde seyreltilmiş virüs bağlama çalışmaları yapmak için alternatif bir serum virüsü eki ile girişime neden olup olmadığını belirlemek için, düşük serum konsantrasyonu (% 2) ve uygun bir tampon maddesi ile PBS içeren bir minimal ortamda kullanmak gibi. Alternatif virüsler benzer bağlanma protokolleri bicarbo olmayan RPMI 1640 ortam maddesinin kullanımını bildirmiştir% 0.2 sığır serum albümini, 10 mM (2- (morfolino) etansülfonik asit) ihtiva eden Nate, ve 10 mM HEPES, pH 6.8 32. Bu bağlanma ortamı ortam kuluçka CO2-çevre çıkarıldığında ortaya çıkabilir, pH değişiklikleri önlemek için üstün olabilir. <ol><li> nonprodüktif eki olayları sınırlamak için 200 2,000 arasında değişen pfus ile kuyu inoküle edin. Şekil 2&#39;de gösterildiği gibi, bu deney kadar az 20&#39;ye PFU (veya en çok 6 10 x 2 PFU) ile ek saptayabilir. </li><li> hücreleri üzerine aşılama için virüs ana karışımı oluşturun. Her bir virüs örneği göz başına 50 ul hacim içinde suret kuyu üzerine inoküle edilir. oyuk başına virüs 2.000 pfus eklenmesi isteniyorsa, bu nedenle, DMEM tam soğuk buz 120 ul toplam hacmine 4800 pfus seyreltin. <ol><li> testin özelliğini kontrol etmek için, her iki TfR1 (TRVb) veya EXP ifade yoktur Çin hamsteri yumurtalık hücresi hatları eşleşen bir çift kullanımıbu hücrelere JUNV eki olarak Arş hTfR1 (TRVb-1) düşük ya da sırasıyla 13,33 olmalıdır, ya. Alternatif olarak, arenavirüs eki 34 veya girişi 35 engellemek için böyle proteinaz K gibi bir proteaz hücreleri davranın. Hücrelerle 13,36 içine JUNV girişini engellemek için bilindiği gibi hTfR1 için spesifik olan çözünür hTfR1 ya monocolonal antikor ch128.1, aynı zamanda kabul edilebilir. Ayrıca, serbest manoz 14 veya JUNV spesifik nötralize edici antikorlar 37 partikül inkübasyon hücrelerin ön-muamele virüs girişi inhibe edebilir. </li><li> Bu olası bir açıklama olmasına rağmen JUNV girişini engelleme rağmen bu son reaktifler ve yaklaşımlar, eki engellemek için teyit edilmemiş olması, ancak unutmayın. Burada açıklanan protokol resmen bu çeşitli yaklaşımlar darbe virion eki olup olmadığını belirlemek için kullanılabilir. </li></ol></li></ol></li><li> 37 ° C inkübatör plakaları çıkarın veyer ya da 4 ° C buzdolabı ya da 15 dakika endositoz gerçekleştirmek için kaplama hücrelerinin yeteneğini inhibe etmek için buz üzerinde. </li><li> Daha sonra, her bir gözden bitmiş DMEM aspire hızla buz soğukluğunda PBS (fosfat tamponlu tuz), pH 7.4, 100 ul kullanılarak iki kez her bir yıkama. Daha sonra uygun oyuklara (adım 2.1 hazırlanmış) öncesi seyreltilmiş virüs örneklerinin 50 ul ekleyin. </li><li> plastik wrap plaka sarın ve hemen geri buz üzerinde veya virüs eki meydana gelmesine izin için 1 saat 1.5 için bir 4 ° C buzdolabında ya yerleştirin. Bu adımı boyunca, 4 ° C&#39;de soğuk plaka tutun yıkama tamponu ve virüs örnekleri. </li><li> 4 ° C&#39;de inkübasyonun tamamlanmasından sonra, virüs inokulum aspirat ve buz soğukluğunda PBS 200 ul her bir göze 3 kez yıkayın. </li></ol> 3. Viral RNA Ekstraksiyon <ol><li> (Örneğin, RNeasy Mini kiti) Accor ticari kit kullanılarak JUNV C # mono tabakaları bağlı 1 parçacıkların viral RNA arındırmaküreticinin protokolüne ding. Özellikle, aşağıda listelenen değişikliklerle RNeasy Mini El Kitabı&#39;nda sayfa 23-28 (4. Baskı, Nisan 2006) üzerine &quot;spin teknolojisi protokolünü kullanarak hayvan hücrelerinden toplam RNA&#39;nın saflaştırılması&quot; izleyin. <ol><li> Lyse her kuyuya doğrudan lizis tamponu RLT 350 ul ekleyerek adım 1B belirtildiği gibi hücreler. Hücre lizizi sağlamak için bir tampon birkaç kez karıştırılır. hücreleri kolayca bu tamponda parçalanmayabilir ve tam lizis ters mikroskop altında kuyu görüntüleyerek kontrol edilebilir unutmayın. </li><li> Kit kolonu (adım 3a) elde edilen hücre lizatının aktarın ve açıklandığı gibi protokol kalanını izleyin. protokol kalan adımları sınıf II biyo-güvenlik kabininin dışında yapılan kiti borular bulaşıcı bir virüs ile kontamine değil sağlanabilir, böylece, bu noktada, virüs lizis tamponu ile nötralize edilmiştir. </li><li> Bir addit olan üreticinin protokolüne gelen isteğe bağlı adım 9 DahilSpin sütunun ional santrifüj Tampon RPE olası taşınmasını ortadan kaldırmak için. </li><li> Son adımda üreticinin protokolü (adım 10), nükleaz içermeyen GKD 2 O. 30 ul kullanarak spin kolon saflaştırılmış RNA Zehir Mağaza bu noktada 80 ° C&#39;de RNA veya QRT-PCR deneyinde doğrudan kullanımı. nükleazlar tarafından saflaştırılmış viral RNA örnekleri bozulmasını önlemek için, nükleaz içermeyen reaktifler ve ekipman kullanımı ve buz üzerinde eritildi RNA örnekleri tutun. Not: Tamponlar RLT ve RW1 guanidin tuzu içeren ve ağartıcı ile karıştırılmamalıdır. Tampon RW1 etanol içerir. </li></ol></li></ol> Viral genomunun 4. QRT-PCR Ölçümü <ol><li> daha sonra qPCR cDNA&#39;ya JUNV Cı 1. S kademeli bir RNA dönüştürmek için 50 ul bir toplam hacim içinde oda sıcaklığına (adım 3.1.4 üretilen), viral RNA tabi. <ol><li> nuclease 6.75 ul: RT reaksiyonu kurmak için, öncelikle reaksiyon başına aşağıdaki reaktiflerin her içeren bir master karışımı oluşturmakiçermeyen GKD 2, O, RT primer G 2 uM stokunun 5 ul 2098- 2075- S kademeli bir genomik RNA&#39;nın NP bölgesi, 5 ul bir tamamlayıcı olan (5&#39;-AAGGGTTTAAAAATGGTAGCAGAC-3 &#39;), 10X PCR tampon II, 25 mM MgCl2 çözeltisi 11 ul RT enziminin, RNaz inhibitörü 1 ul (0.4 ünite), 1.25 ul (62.5 Birimleri) ve dNTP 500 uM stokunun 10 ul. Not: arenavirüs replikasyon esnasında, 4, viral S kademeli bir RNA türlerinin oluşturulur: tam boy bir genomik RNA (vRNA), tam uzunluklu antigenomik RNA (vcRNA) (diğer bir deyişle vRNA ters tamamlayıcı olan) ve iki alt-genomik mRNA sırasıyla PN ve GP genlerini kodlayan. Burada yer alan RT primeri sadece S segmenti vRNA için spesifik olan, ancak vcRNA NP mRNA veya GP mRNA. </li><li> Yavaşça RT ana karışımı karıştırın ve daha sonra tek tek 0.2 ml PCR tüplerine 40 ul bölmeyin. Her tüpe, viral RNA 10 ul ekle. Dahil i) hiçbir şablon kontrol tüpü (örn. Nükleaz içermeyen GKD 2 O 40 ana karışımı uL) ve ii) herhangi bir RT enzim karşılaştırma 10 ul (örneğin almadı ana karışımı 40 ul, bilinen bir pozitif viral RNA numunesinin 10 ul ekle bir RT enzim), viral bir hedef sekansı içeren amplifiye DNA RT reaktiflerin kirlenme taranması için. hücresel RNA mevcudiyetinde deney özgüllük için kontrol tamamına RT ana karışımı ile enfekte olmamış hücrelerden çıkarılan RNA içerir. </li><li> Buna ek olarak, RT reaktiflerin kalitesini doğrulamak için tam ana karışımı bilinen pozitif viral RNA örnek sayılabilir. gerektiğinde RT reaksiyon hacmi 25 ul indirgenebilir unutmayın. </li></ol></li><li> Aşağıdaki bisiklet koşulları RT tüpler Konu: 25 ° C, 10 dakika, 30 dakika boyunca 48 ° C, 5 dakika için 95 ° C. Numuneler 4 ° C&#39;de adım eklenmesi ile bu noktada -20 ° C&#39;de saklandı veya PCR gece boyunca bırakılabilir unutmayın. </li><li> P25 ul bir toplam hacimde erform qPCR. <ol><li> Aşağıdaki birleştirerek bir qPCR ana karışımı yapmak: her S1937 + 1958+ ileri PCR primeri (5&#39;-CATGGAGGTCAAACAACTTCCT-3 &#39;) (9 uM stoklar) 2.5 ul ve ters PCR primeri G 2001 için 1982 (5 için qPCR prob S 1960+ arasında &#39;-GCCTCCAGACATGGTTGTGA-3&#39;), 2 uM stokunun 2.5 ul () 1975+ (5&#39;-6FAM-ATGTCATCGGATCCTT-MGBNFQ-3 &#39;) ve 2X genel qPCR ana 12.5 ul karıştırın. JUNV C # 1 için spesifik burada bildirilen ileri primer, nt öldürücü JUNV zorlanma Romero hedef başlangıçta bildirilen primer dizisinin 38 dan 1 ile farklı olduğunu unutmayın. </li><li> Yavaşça çözüm karıştırmak ve sonra her bir qPCR 20 ul ekleyin. Uygun QPCR çukurlara, her bir RT reaksiyonu 5 ul ekle. Test edilen her bir numune için üç kopya halinde qPCR yürütün. Gerekirse PCR reaksiyon hacmi az 12.5 olduğu ul indirgenebilir unutmayın. Not: ile bağlantılı yazılımqPCR makinesi QPCR primer hedef JUNV Cı 1. NP genini kodlayan plasmid standart seyreltilmiş bir dizi her bilinmeyen numune değerinin karşılaştırılmasıyla JUNV Cı 1. S kademeli bir genomik RNA&#39;nın mutlak kopya sayıları üretir ve sonda ayarlayın. qPCR testi sadece standart eğri aralığı içinde değerleri kantitatif sağlayabilir. 5, 50 x 10 3 5, 5 x 10 5, 5 x 10 7 adet çukur başına Bu nedenle, aşağıdaki gibidir (üçlü kuyucuklara) plazmidinin miktarlarını içerir. </li></ol></li><li> ısıl olarak qPCR plaka yükleme ve aşağıdaki reaksiyon koşulları çalıştırın: 95 ° C, 10 dakika, 15 saniye, 1 dakika için 60 ° C, 95 ° C, 40 çevrim için. <ol><li> Toplama ve üreticinin protokolüne uygun olarak, her numune viral RNA mevcut miktarını belirlemek için veri analizi. </li></ol></li><li> qPCR katran ihtiva eden plazmit, bir yeni saflaştınldı numune kullanılarak bir standart eğri oluşturmak içindizisi olsun, öncelikle bu çözelti içinde plazmid kopya sayısını belirlemek. <ol><li> plazmidin moleküler ağırlığı hesaplamak. Tüm plazmidin dizisi biliniyorsa, aşağıdaki formülü kullanarak bu hesaplayın: MW = ([A * 312.2] + [G * 328.2] + [C * 288.2] + [T * 303.2] - 61,13). çift ​​sarmallı plazmid her iplikçik üzerinde bulunan belirli bir nükleotid toplam sayısını eklemeyi unutmayın. </li><li> plazmid büyüklüğü bilinen ama onun tam sırası değil ise, her dsDNA baz çifti 600 MW vardır varsayımı altında MW hesaplayın. Not: Burada kullanılan pCAGGS-JUNV C # 1 NP plazmid 4.2 x 10 6 Bir MW vardır. </li><li> plazmidin MW belirlendikten sonra, ul başına çok sayıda kopya plazmid hazır çözelti içinde mevcut olduğunu hesaplayabilir. </li><li> İlk çözelti içinde plazmid toplam ug hesaplamak, daha sonra plazmid mol bu dönüştürmek (plazmid 69 mikrogram daha sonra su 300 ul, 6,9 x 1 içerdiği, örneğin eğerKopya sayısı dönüştürülebilir plazmid * 1 mol 0 5 g / plazmid 4.2 x 10 6 g = plazmid 1.6 x 10 -11 mol), (örneğin, plazmid 1.6 x 10 -11 mol * 6,022 x, 10&#39;dan 23 moleküller / mol = 9.8 x 10 12 molekülleri (veya kopya)). </li><li> Ul başına kopya elde etmek için bu çözeltinin hacimce plazmid çözeltisi plazmidin toplam kopyalarını bölün (örneğin 9.8 x 10 12 kopya / 300 ul = 3.28 x 10 10 kopya). </li><li> 5 ul hacim standart eğri oluşturmak için gerekli kopyalama sayı aralığı sağlamak için PCR plakasına yerleştirilir, böylece uygun bir şekilde, bu solüsyon ile seyreltilir. </li></ol></li></ol>

<ol>
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R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=siRNA+screen+for+genes+that+affect+Junin+virus+entry+uncovers+voltage-gated+calcium+channels+as+a+therapeutic+target.">siRNA screen for genes that affect Junin virus entry uncovers voltage-gated calcium channels as a therapeutic target.</a> Sci Transl Med. 5, 204ra131 (2013).</li><li>Ellenberg, P., Edreira, M., Scolaro, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Resistance+to+superinfection+of+Vero+cells+persistently+infected+with+Junin+virus.">Resistance to superinfection of Vero cells persistently infected with Junin virus.</a> Arch. Virol. 149, 507-522 (2004).</li><li>Brandenburg, 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=Imaging+poliovirus+entry+in+live+cells.">Imaging poliovirus entry in live cells.</a> PLoS Biol. 5, e183 (2007).</li><li>Petersen, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Major+Cellular+Sterol+Regulatory+Pathway+Is+Required+for+Andes+Virus+Infection.">The Major Cellular Sterol Regulatory Pathway Is Required for Andes Virus Infection.</a> PLoS pathogens. 10, e1003911 (2014).</li><li>Jonsson, N., Gullberg, M., Israelsson, S., Lindberg, A. M. <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+and+efficient+method+for+studies+of+virus+interaction+at+the+host+cell+surface+using+enteroviruses+and+real-time+PCR.">A rapid and efficient method for studies of virus interaction at the host cell surface using enteroviruses and real-time PCR.</a> Virol J. 6, 217 (2009).</li><li>Jiang, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hepatitis+C+virus+attachment+mediated+by+apolipoprotein+E+binding+to+cell+surface+heparan+sulfate.">Hepatitis C virus attachment mediated by apolipoprotein E binding to cell surface heparan sulfate.</a> J. Virol. 86, 7256-7267 (2012).</li><li>Shannon-Lowe, 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=Epstein-Barr+virus-induced+B-cell+transformation:+quantitating+events+from+virus+binding+to+cell+outgrowth.">Epstein-Barr virus-induced B-cell transformation: quantitating events from virus binding to cell outgrowth.</a> J. Gen. Virol. 86, 3009-3019 (2005).</li><li>Mifflin, T. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Setting+up+a+PCR+laboratory.">Setting up a PCR laboratory.</a> CSH Protoc. 2007, pdb top14 (2007).</li><li>Maiztegui, J. I., 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=Protective+efficacy+of+a+live+attenuated+vaccine+against+Argentine+hemorrhagic+fever.+AHF+Study+Group.">Protective efficacy of a live attenuated vaccine against Argentine hemorrhagic fever. AHF Study Group.</a> J. Infect. Dis. 177, 277-283 (1998).</li><li>Goni, S. 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=Genomic+features+of+attenuated+Junin+virus+vaccine+strain+candidate.">Genomic features of attenuated Junin virus vaccine strain candidate.</a> Virus Genes. 32, 37-41 (2006).</li><li>Chosewood, L. C., Wilson, D. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Biosafety in microbiological and biomedical laboratories. , (2009).</li><li>White, J., Matlin, K., Helenius, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+fusion+by+Semliki+Forest,+influenza,+and+vesicular+stomatitis+viruses.">Cell fusion by Semliki Forest, influenza, and vesicular stomatitis viruses.</a> J. Cell Biol. 89, 674-679 (1981).</li><li>McGraw, T. E., Greenfield, L., Maxfield, F. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functional+expression+of+the+human+transferrin+receptor+cDNA+in+Chinese+hamster+ovary+cells+deficient+in+endogenous+transferrin+receptor.">Functional expression of the human transferrin receptor cDNA in Chinese hamster ovary cells deficient in endogenous transferrin receptor.</a> J. Cell Biol. 105, 207-214 (1987).</li><li>Borrow, P., Oldstone, M. B. <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+lymphocytic+choriomeningitis+virus-binding+protein(s):+a+candidate+cellular+receptor+for+the+virus.">Characterization of lymphocytic choriomeningitis virus-binding protein(s): a candidate cellular receptor for the virus.</a> J. Virol. 66, 7270-7281 (1992).</li><li>Rojek, J. M., Spiropoulou, C. F., Kunz, S. <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+cellular+receptors+for+the+South+American+hemorrhagic+fever+viruses+Junin,+Guanarito,+and+Machupo.">Characterization of the cellular receptors for the South American hemorrhagic fever viruses Junin, Guanarito, and Machupo.</a> 346. , 476-491 (2006).</li><li>Helguera, G., 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=An+antibody+recognizing+the+apical+domain+of+human+transferrin+receptor+1+efficiently+inhibits+the+entry+of+all+new+world+hemorrhagic+Fever+arenaviruses.">An antibody recognizing the apical domain of human transferrin receptor 1 efficiently inhibits the entry of all new world hemorrhagic Fever arenaviruses.</a> J. Virol. 86, 4024-4028 (2012).</li><li>Sanchez, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Junin+virus+monoclonal+antibodies:+characterization+and+cross-reactivity+with+other+arenaviruses.">Junin virus monoclonal antibodies: characterization and cross-reactivity with other arenaviruses.</a> J. Gen. Virol. 70, 1125-1132 (1989).</li><li>Trombley, A. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+panel+of+real-time+TaqMan+polymerase+chain+reaction+assays+for+detection+and+absolute+quantification+of+filoviruses,+arenaviruses,+and+New+World+hantaviruses.">Comprehensive panel of real-time TaqMan polymerase chain reaction assays for detection and absolute quantification of filoviruses, arenaviruses, and New World hantaviruses.</a> Am. J. Trop. Med. Hyg. 82, 954-960 (2010).</li><li>Helenius, A., Marsh, M., White, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+Semliki+forest+virus+penetration+by+lysosomotropic+weak+bases.">Inhibition of Semliki forest virus penetration by lysosomotropic weak bases.</a> J. Gen. Virol. 58 (Pt 1), 47-61 (1982).</li><li>Nour, A. M., Li, Y., Wolenski, J., Modis, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Viral+membrane+fusion+and+nucleocapsid+delivery+into+the+cytoplasm+are+distinct+events+in+some+flaviviruses.">Viral membrane fusion and nucleocapsid delivery into the cytoplasm are distinct events in some flaviviruses.</a> PLoS pathogens. 9, e1003585 (2013).</li></ol>

Yazarlar hiçbir rakip mali çıkarları olduğunu beyan ederim.

biz tarif protokol basittir ve sağlam aşağıdaki kritik hususlar görülmektedir sağladı. İlk olarak, sıkı öncesi PCR tekniği (mükemmel bir inceleme için 28 bakınız) istihdam edilmelidir. Tüm reaktifler ve ekipmanlar qPCR hedef sekansı içeren amplifiye DNA içermeyen ve uygun kontrol gibi kirlenmesini tespit etmek için bir yerde olması önemlidir. İkinci olarak, iletişim kuralı, virüs, hücreler ve ortamın virüs-hücre bağlanma bölümü için yüzeyine bağlı viryonlann endositoz ?...

Arenaviruses doğada 1-3, kemirgenlerde esas korunur saran, tek iplikçikli RNA virüslerinden oluşan bir ailesidir. Bu virüsler genellikle kemirgen rezervuarların 1,2 asemptomatik, kalıcı enfeksiyon kurmak olsa da, insanlarda 3 şiddetli hastalığa neden olabilir. Önemli patojenik türler Yeni Dünya Junin virüsü (JUNV) 4 ve Afrika&#39;da Güney Amerika ve Lassa ateş Arjantin hemorajik ateş etiyolojik ajanları sırasıyla, Old World Lassa virüsü 5 içerir. Lenfositik koryomenenjit virüsü (LCMV), ailenin 6 prototipik virüs, dünya çapında bir dağılımına sahiptir ve bağışıklık sistemi baskılanmış olarak immün sistemi sağlıklı bireylerde 6 aseptik menenjit, gelişmekte olan fetusta 7 ciddi doğum kusurlarına veya yüksek öldürücülüğü dahil hastalık durumlarında çeşitli sorumludur solid organ transplantasyonu 8,9 aşağıdaki bireyler. Amerika Birleşik Devletleri eksikliğiGıda ve İlaç İdaresi (FDA) aşılar ya da bu virüs ile mücadele için etkili antiviral tedavi, ortaya çıkan bu / yeniden ortaya çıkan patojenleri hedef yeni stratejiler geliştirmek için kritik ihtiyacının altını çizmektedir -onaylı. Arenavirüs genomu iki tek-şeritli RNA segmenti, büyük (L) (~ 7.2 kb) ile küçük (S), (~ 3.6 kb) segmentleri 10 oluşur. L kademeli bir viral polimeraz (L) ve matris protein (Z) kodlar ise S kademeli bir virüs nükleoprotein (NP) ve zarf glikoproteini (GP) kodlar. L ve S genomik RNA segmenti (vRNAs) virionlar 10-12 içinde ambalajlandı. Arenavirüs enfeksiyonun başlangıç ​​aşaması, viral parçacıkların ek JUNV için, insan transferin reseptörü 1 (hTfR1) 13,14 içerir viral GP ve karşılık gelen konakçı hücre reseptörleri arasındaki bir etkileşim yoluyla konakçı hücreler sağlamaktır. Bağlanmasının ardından, JUNV parçacıklar klatrin dolayımlı endositoz 15 ile hücre içine alınır.Parçacıklar bu bölmenin düşük pH GP 16,17 aktivasyonunu tetikler geç Endozom sonra trafik. Bir kez viral ve endozomal membranların arasındaki kaynaşmayı başlatarak, GP-kodlanmış füzyon peptid ekler endozomal zarı içine, aktif. Onlar genomik replikasyon ve transkripsiyon için şablon olarak hizmet sitoplazma içine viryon paketlenmiş vRNAs serbest bırakılması Başarılı füzyon sonuçları. Viral yapısal proteinler ve vRNAs yeterli miktarda üretilir, yeni parçacıkların araya ve enfekte olmuş hücreden tomurcuk ömrü 18 tamamlayın. terapötik patojenik arenaviruses hedeflenecek yeni stratejilerin keşfini kolaylaştırmak için, bizim grup ev sahibi için virüs yayılımı için kritik, ama vazgeçilebilir olan konak faktörlerinin belirlenmesi üzerine odaklanmıştır. Bu bağlamda, bu gibi konakçı faktör ile kontrol virüs ömrü çevrimi kesin aşama (lar) tanımlayan kılavuz için gerekli olanAntiviral stratejilerin geliştirilmesi. Burada, seçilen konakçı proteinleri ve / veya antiviral moleküller viral giriş 19, bu ilk aşamasına etkileyen olmadığının belirlenmesi amacıyla, arenavirüs hücre eki ölçmek için kullanılabilecek bir miktar (Q), RT-PCR bazlı analiz tarif eder. Arenavirüs hücre eki ölçmek için alternatif yaklaşımlar biyotin 20, floresan boyalar 21 veya radyoaktif izotoplar 22 ile etiketlenmiş virionlar özellikli var. Bu yöntemlere dezavantajları, giriş virüsünün büyük miktarlarda radyoaktivite kullanımı (enfeksiyon (MOI) arasında örneğin yüksek çokluklar), ve / veya girdi virüs (örneğin, konsantrasyon ve / veya virüs etiketleme) hazırlanması için ek işleme adımları için gereksinimi içerebilir . Özellikle, yüksek İçişleri kullanımı zor nonprodüktif eki olayları 15,23 karşı üretken ayırt etmek yapar. Burada anlatılan QRT-PCR tabanlı tahlil kadar az 20 olarak plaket kullanılarak eki olaylarını algılayabilirMing birimleri, 48-delikli plaka için 0.0004 MOI anlamına virüs (pfus). Bu nedenle, tahlil güçlü duyarlılığı yüksek İçişleri Bakanlığı için gereksinimi yanı sıra herhangi bir virüs etiketleme ya da konsantrasyon adımları üstesinden gelir. Bundan başka, deney I) viryon endositozu ölçmek hem de sitoplazmaya virüs genomunun serbest bırakılması gibi füzyon şu şekilde uyarlanmış ii) örnekleri için virüs özel QRT-PCR geliştirilmesi yoluyla diğer virüsler ile kullanım için (özel olabilir, bkz 24-27).

<table border="0" cellpadding="0" cellspacing="0" width="730">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">DMEM</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">11965-118</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">Penicillin-Streptomycin</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">15140-163</td>
			<td style="width:160px;">100x</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">HEPES Buffer Solution</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">15630-130</td>
			<td style="width:160px;">100x</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">PBS pH 7.4</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">10010-023</td>
			<td style="width:160px;">1x</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">Vero E6 cells</td>
			<td style="width:131px;">American Type Culture Collection</td>
			<td style="width:141px;">CRL-1586</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">Costar 48-well plate</td>
			<td style="width:131px;">Corning</td>
			<td style="width:141px;">3548</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">RNeasy mini kit</td>
			<td style="width:131px;">Qiagen</td>
			<td style="width:141px;">74106</td>
			<td style="width:160px;">do not mix buffers RLT or&#160; RW1 with bleach</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">QIAshredder homogenizer</td>
			<td style="width:131px;">Qiagen</td>
			<td style="width:141px;">79654</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">Taqman Universal PCR Master Mix</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4326614</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">Multiscribe Reverse Transcriptase (50U/&#181;l)</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4311235</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">dNTP Mixture (10 mM; 2.5 mM each dNTP)</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">N808-0260</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">GeneAmp 10X PCR Buffer II and 25 mM MgCl2 solution</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">N808-0010</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:299px;">RNase Inhibitor (5000U/100 &#181;l)</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">N808-0119</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">RT primer 5&#8217;-AAGGGTTTAAAAATGGTAGCAGAC-3&#8217;</td>
			<td style="width:131px;">Integrated DNA Technologies</td>
			<td style="width:141px;">250 nmol DNA oligo</td>
			<td style="width:160px;">standard desalting</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">Forward qPCR primer&#160; 5&#8217;-CATGGAGGTCAAACAACTTCCT-3&#8217;</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4304971</td>
			<td style="width:160px;">standard desalting</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">Reverse qPCR primer 5&#8217;-GCCTCCAGACATGGTTGTGA-3&#8217;</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4304971</td>
			<td style="width:160px;">standard desalting</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">TaqMan Probe 5&#8217;-6FAM-ATGTCATCGGATCCTT-MGBNFQ-3&#8217;</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4316033</td>
			<td style="width:160px;">HPLC purified</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">MicroAmp Fast Optical 96-well reaction plate (0.1 mL)</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4346906</td>
			<td style="width:160px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:299px;">StepOnePlus Real-Time PCR System</td>
			<td style="width:131px;">Life Technologies</td>
			<td style="width:141px;">4376598</td>
			<td style="width:160px;">or other qPCR instrument</td>
		</tr>
	</tbody>
</table>

highly sensitive assay for measurement of arenavirus-cell attachment

Arenaviruses are a family of enveloped RNA viruses that cause severe human disease. The first step in the arenavirus life cycle is attachment of viral particles to host cells. While virus-cell attachment can be measured through the use of virions labeled with biotin, radioactive isotopes, or fluorescent dyes, these approaches typically require high multiplicities of infection (MOI) to enable detection of bound virus. We describe a quantitative (q)RT-PCR-based assay that measures Junin virus strain Candid 1 attachment via quantitation of virion-packaged viral genomic RNA. This assay has several advantages including its extreme sensitivity and ability to measure attachment over a large dynamic range of MOIs without the need to purify or label input virus. Importantly, this approach can be easily tailored for use with other viruses through the use of virus-specific qRT-PCR reagents. Further, this assay can be modified to permit measurement of particle endocytosis and genome uncoating. In conclusion, we describe a simple, yet robust assay for highly sensitive measurement of arenavirus-cell attachment.

Protokol bölüm 4&#39;te tarif edildiği gibi qPCR tahlilin hassasiyetini ve dinamik aralığını göstermek için, JUNV Cı 1. (aralık 5-5 x 10 7 kopya) NP genini kodlayan bir plazmid bilinen miktarlarda qPCR tabi tutuldu. Deney hassastır ve güvenilir bir şekilde, hedef nükleik asidin 5 kopya (Şekil 2) gibi birkaç algılayabilir. Şablonun en az 7 günlükleri kapsayabilir, Şekil 2&#39;de de gösterildiği gibi, tahlilin dinamik ara...

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Highly Sensitive Assay for Measurement of Arenavirus-cell Attachment

The first step in the arenavirus life cycle is attachment of viral particles to host cells. We report a quantitative (q)RT-PCR-based assay for ultrasensitive detection and quantitation of arenavirus attachment events.

Arenavirüs hücre Ek Ölçümü için son derece hassas Deneyi

Arenaviruses are a family of enveloped RNA viruses that cause severe human disease. The first step in the arenavirus life cycle is attachment of viral ...

highly-sensitive-assay-for-measurement-of-arenavirus-cell-attachment

Research

JoVE Journal

Immunology and Infection

9.5K Görüntüleme.  University of Vermont. The first step in the arenavirus life cycle is attachment of viral particles to host cells. We report a quantitative (q)RT-PCR-based assay for ultrasensitive detection and quantitation of arenavirus attachment events.

Video: Highly Sensitive Assay for Measurement of Arenavirus-cell Attachment

Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient

Toxoplasma gondii is an obligate intracellular protozoan pathogen that commonly infects humans. It is a well characterized apicomplexan associated with causing food- and water-borne disease outbreaks. The definitive host is the feline species where sexual replication occurs resulting in the development of the highly infectious and environmentally resistant oocyst. Infection occurs via ingestion of tissue cysts from contaminated meat or oocysts from soil or water. Infection is typically asymptomatic in healthy individuals, but results in a life-long latent infection that can reactivate causing toxoplasmic encephalitis and death if the individual becomes immunocompromised. Meat contaminated with T. gondii cysts have been the primary source of infection in Europe and the United States, but recent changes in animal management and husbandry practices and improved food handling and processing procedures have significantly reduced the prevalence of T. gondii cysts in meat1, 2. Nonetheless, seroprevalence in humans remains relatively high suggesting that exposure from oocyst contaminated soil or water is likely. Indeed, waterborne outbreaks of toxoplasmosis have been reported worldwide supporting the theory exposure to the environmental oocyst form poses a significant health risk3-5. To date, research on understanding the prevalence of T. gondii oocysts in the water and environment are limited due to the lack of tools to detect oocysts in the environment 5, 6. This is primarily due to the lack of efficient purification protocols for obtaining large numbers of highly purified T gondii oocysts from infected cats for research purposes. This study describes the development of a modified CsCl method that easily purifies T. gondii oocysts from feces of infected cats that are suitable for molecular biological and tissue culture manipulation7.

Obtaining Highly Purified Toxoplasma gondii Oocysts by a Discontinuous Cesium Chloride Gradient

This study describes the development of a modified CsCl method that easily purifies T. gondii oocysts from feces of infected cats that are suitable for molecular biological and tissue culture manipulation

Yüksek Saflaştırılmış Alınması Toxoplasma gondii Süreksiz Sezyum Klorür Gradient ookistleri

Toxoplasma gondii is an obligate intracellular protozoan pathogen that commonly infects humans. It is a well characterized apicomplexan associated with ...

İmmünoloji ve Enfeksiyon

Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay

In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin which forms an insoluble clot that stops hemorrhage. Factor V (FV) in its activated form, FVa, is a critical cofactor for the protease FXa and accelerator of thrombin generation during fibrin clot formation as part of prothrombinase 1, 2. Manual FV assays have been described 3, 4, but they are time consuming and subjective. Automated FV assays have been reported 5-7, but the analyzer and reagents are expensive and generally provide only the clot time, not the rate and extent of fibrin formation. The microplate platform is preferred for measuring enzyme-catalyzed events because of convenience, time, cost, small volume, continuous monitoring, and high-throughput 8, 9. Microplate assays have been reported for clot lysis 10, platelet aggregation 11, and coagulation Factors 12, but not for FV activity in human plasma. The goal of the method was to develop a microplate assay that measures FV activity during fibrin formation in human plasma.
This novel microplate method outlines a simple, inexpensive, and rapid assay of FV activity in human plasma. The assay utilizes a kinetic microplate reader to monitor the absorbance change at 405nm during fibrin formation in human plasma (Figure 1) 13. The assay accurately measures the time, initial rate, and extent of fibrin clot formation. It requires only &mu;l quantities of plasma, is complete in 6 min, has high-throughput, is sensitive to 24-80pM FV, and measures the amount of unintentionally activated (1-stage activity) and thrombin-activated FV (2-stage activity) to obtain a complete assessment of its total functional activity (2-stage activity - 1-stage activity).
Disseminated intravascular coagulation (DIC) is an acquired coagulopathy that most often develops from pre-existing infections 14. DIC is associated with a poor prognosis and increases mortality above the pre-existing pathology 15. The assay was used to show that in 9 patients with DIC, the FV 1-stage, 2-stage, and total activities were decreased, on average, by 54%, 44%, and 42%, respectively, compared with normal pooled human reference plasma (NHP).
The FV microplate assay is easily adaptable to measure the activity of any coagulation factor. This assay will increase our understanding of FV biochemistry through a more accurate and complete measurement of its activity in research and clinical settings. This information will positively impact healthcare environments through earlier diagnosis and development of more effective treatments for coagulation disorders, such as DIC.

This study describes a novel microplate assay that measures FV coagulation activity during fibrin clot formation in human plasma which has not been reported previously. The method uses a kinetic microplate reader to continuously measure the change in absorbance at 405nm during fibrin clot formation in human plasma.

Bir Mikroplaka Pıhtılaşma Analiz Kullanarak İnsan Plazma Faktör V Aktivitenin Ölçümü

 In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin ...

Plaque Assay for Murine Norovirus

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are observed during MNV-1 infection of murine dendritic cells or macrophages 1. This property of MNV-1 can be used to quantify the number of infectious particles in a given sample by performing a plaque assay 1. The plaque assay relies on the ability of MNV-1 to lyse cells and to form holes in a confluent cell monolayer, which are called plaques 3.
Multiple techniques can be used to detect viral infections in tissue culture, harvested tissue, clinical, and environmental samples, but not all measure the number of infectious particles (e.g. qRT-PCR). One way to quantify infectious viral particles is to perform a plaque assay 3, which will be described in detail below. A variation on the MNV plaque assay is the fluorescent focus assay, where MNV antigen is immunostained in cell monolayers 4. This assay can be faster, since viral antigen expression precedes plaque formation. It is also useful for titrating viruses unable to form plaques. However, the fluorescent focus assay requires additional resources beyond those of the plaque assay, such as antibodies and a microscope to count focus-forming units. Infectious MNV can also be quantified by determining the 50% Tissue Culture Infective Dose (TCID50) 3. This assay measures the amount of virus required to produce CPE in 50% of inoculated tissue culture cells by endpoint titration 5. However, its limit of detection is higher compared to a plaque assay 4.
In this article, we describe a plaque assay protocol that can be used to effectively determine the number of infectious MNV particles present in biological or environmental samples 1, 4, 6. This method is based on the preparation of 10-fold serial dilutions of MNV-containing samples, which are used to inoculate a monolayer of permissive cells (RAW 264.7 murine macrophage cells). Virus is allowed to attach to the cell monolayer for a given period of time and then aspirated before covering cells with a mixture of agarose and cell culture media. The agar enables the spread of viral progeny to neighboring cells while limiting spread to distantly located cells. Consequently, infected cells are lysed and form holes in the monolayer known as plaques. Upon sufficient spread of virus, plaques become visible following staining of cells with dyes, like neutral red, methylene blue, or crystal violet. At low dilutions, each plaque originates from one infectious viral particle and its progeny, which spread to neighboring cells. Thus, counting the number of plaques allows one to calculate plaque-forming units (PFU) present in the undiluted sample 3.

Here we describe a method to quantify infectious particles of murine norovirus (MNV), which is the only norovirus that efficiently replicates in cell culture. The plaque assay takes advantage of MNV&#x2019;s tropism for murine macrophages and can be adapted for use with biological or environmental samples containing MNV.

Mürin Norovirüs için Plak Testi

Murine norovirus (MNV) is the only member of the Norovirus genus that efficiently grows in tissue culture 1, 2. Cell lysis and cytopathic effect (CPE) are ...

Quantitative Measurement of the Immune Response and Sleep in Drosophila

A complex interaction between the immune response and host behavior has been described in a wide range of species. Excess sleep, in particular, is known to occur as a response to infection in mammals 1 and has also recently been described in Drosophila melanogaster2. It is generally accepted that sleep is beneficial to the host during an infection and that it is important for the maintenance of a robust immune system3,4. However, experimental evidence that supports this hypothesis is limited4, and the function of excess sleep during an immune response remains unclear. We have used a multidisciplinary approach to address this complex problem, and have conducted studies in the simple genetic model system, the fruitfly Drosophila melanogaster. We use a standard assay for measuring locomotor behavior and sleep in flies, and demonstrate how this assay is used to measure behavior in flies infected with a pathogenic strain of bacteria. This assay is also useful for monitoring the duration of survival in individual flies during an infection. Additional measures of immune function include the ability of flies to clear an infection and the activation of NF&kappa;B, a key transcription factor that is central to the innate immune response in Drosophila. Both survival outcome and bacterial clearance during infection together are indicators of resistance and tolerance to infection. Resistance refers to the ability of flies to clear an infection, while tolerance is defined as the ability of the host to limit damage from an infection and thereby survive despite high levels of pathogen within the system5. Real-time monitoring of NF&kappa;B activity during infection provides insight into a molecular mechanism of survival during infection. The use of Drosophila in these straightforward assays facilitates the genetic and molecular analyses of sleep and the immune response and how these two complex systems are reciprocally influenced.

Quantitative Measurement of the Immune Response and Sleep in Drosophila

To understand a link between the immune response and behavior, we describe a method to measure locomotor behavior in Drosophila during bacterial infection as well as the ability of flies to mount an immune response by monitoring survival, bacterial load, and real-time activity of a key regulator of innate immunity, NF&kappa;B.

İmmün Yanıt ve Uyku içinde kantitatif ölçümü<em&gt; Drosophila</em

A complex interaction between the immune response and  host behavior has been described in a wide range of species. Excess sleep, in  particular, is known ...

Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers

Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick tissue samples and organs in health and disease. By controlling the scanning pattern in multi-photon microscopy and applying appropriate numerical algorithms, we developed a striped-illumination approach, which enabled us to achieve 3-fold better axial resolution and improved signal-to-noise ratio, i.e. contrast, in more than 100 &#181;m tissue depth within highly scattering tissue of lymphoid organs as compared to standard multi-photon microscopy. The acquisition speed as well as photobleaching and photodamage effects were similar to standard photo-multiplier-based technique, whereas the imaging depth was slightly lower due to the use of field detectors. By using the striped-illumination approach, we are able to observe the dynamics of immune complex deposits on secondary follicular dendritic cells &#8211; on the level of a few protein molecules in germinal centers.

High-resolution intravital imaging with enhanced contrast up to 120 &#181;m depth in lymph nodes of adult mice is achieved by spatially modulating the excitation pattern of a multi-focal two-photon microscope. In 100 &#181;m depth we measured resolutions of 487 nm (lateral) and 551 nm (axial), thus circumventing scattering and diffraction limits.

Germinal Merkezleri derece Çözülmüş Intravital Çizgili-aydınlatma Mikroskopi

Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick ...

Highly Efficient Transfection of Human THP-1 Macrophages by Nucleofection

Macrophages, as key players of the innate immune response, are at the focus of research dealing with tissue homeostasis or various pathologies. Transfection with siRNA and plasmid DNA is an efficient tool for studying their function, but transfection of macrophages is not a trivial matter. Although many different approaches for transfection of eukaryotic cells are available, only few allow reliable and efficient transfection of macrophages, but reduced cell vitality and severely altered cell behavior like diminished capability for differentiation or polarization are frequently observed. Therefore a transfection protocol is required that is capable of transferring siRNA and plasmid DNA into macrophages without causing serious side-effects thus allowing the investigation of the effect of the siRNA or plasmid in the context of normal cell behavior. The protocol presented here provides a method for reliably and efficiently transfecting human THP-1 macrophages and monocytes with high cell vitality, high transfection efficiency, and minimal effects on cell behavior. This approach is based on Nucleofection and the protocol has been optimized to maintain maximum capability for cell activation after transfection. The protocol is adequate for adherent cells after detachment as well as cells in suspension, and can be used for small to medium sample numbers. Thus, the method presented is useful for investigating gene regulatory effects during macrophage differentiation and polarization. Apart from presenting results characterizing macrophages transfected according to this protocol in comparison to an alternative chemical method, the impact of cell culture medium selection after transfection on cell behavior is also discussed. The presented data indicate the importance of validating the selection for different experimental settings.

This protocol presents an efficient and reliable method to transfect human THP-1 macrophages with siRNA or plasmid DNA by electroporation with high transfection efficiency while maintaining high cell vitality and full macrophage capacity for differentiation and polarization.

Nucleofection İnsan THP-1 Makrofagların Yüksek Verimli Transfeksiyonu

Macrophages, as key players of the innate immune response, are at the focus of research dealing with tissue homeostasis or various pathologies. ...

Measuring Attachment and Internalization of Influenza A Virus in A549 Cells by Flow Cytometry

Attachment to target cells followed by internalization are the very first steps of the life cycle of influenza A virus (IAV). We provide here a detailed protocol for measuring relative changes in the amount of viral particles that attach to A549 cells, a human lung epithelial cell line, as well as in the amount of particles that are internalized into the cell. We use biotinylated virus which can be easily detected following staining with Cy3-labeled streptavidin (STV-Cy3). We describe the growth, purification and biotinylation of A/WSN/33, a widely used IAV laboratory strain. Cold-bound biotinylated IAV particles on A549 cells are stained with STV-Cy3 and measured using flow cytometry. To investigate uptake of viral particles, cold-bound virus is allowed to internalize at 37 &#176;C. In order to differentiate between external and internalized viral particles, a blocking step is applied: Free binding spots on the biotin of attached virus on the cell surface are bound by unlabeled streptavidin (STV). Subsequent cell permeabilization and staining with STV-Cy3 then enables detection of internalized viral particles. We present a calculation to determine the relative amount of internalized virus. This assay is suitable to measure effects of drug-treatments or other manipulations on attachment or internalization of IAV.

We present a protocol describing a semi-quantitative method for measuring both, the attachment of influenza A virus to A549 cells, as well as the internalization of virus particles into the target cells by flow cytometry.

Akış Sitometrisi ile A549 Hücreleri Eklenti ve içselleştirilmesi Gribi bir virüs Ölçme

Attachment to target cells followed by internalization are the very first steps of the life cycle of influenza A virus (IAV). We provide here a detailed ...

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species

Foodborne infections in the US caused by Vibrio species have shown an upward trend. In the genus Vibrio, V. parahaemolyticus is responsible for the majority of Vibrio-associated infections. Thus, accurate differentiation among Vibrio spp. and detection of V. parahaemolyticus is critically important to ensure the safety of our food supply. Although molecular techniques are increasingly common, culture-depending methods are still routinely done and they are considered standard methods in certain circumstances. Hence, a novel chromogenic agar medium was tested with the goal of providing a better method for isolation and differentiation of clinically relevant Vibrio spp. The protocol compared the sensitivity, specificity and detection limit for the detection of V. parahaemolyticus between the new chromogenic medium and a conventional medium. Various V. parahaemolyticus strains (n=22) representing diverse serotypes and source of origins were used. They were previously identified by Food and Drug Administration (FDA) and Centers for Disease Control and Prevention (CDC), and further verified in our laboratory by tlh-PCR. In at least four separate trials, these strains were inoculated on the chromogenic agar and thiosulfate-citrate-bile salts-sucrose (TCBS) agar, which is the recommended medium for culturing this species, followed by incubation at 35-37 &#176;C for 24-96 hr. Three V. parahaemolyticus strains (13.6%) did not grow optimally on TCBS, nonetheless exhibited green colonies if there was growth. Two strains (9.1%) did not yield the expected cyan colonies on the chromogenic agar. Non-V. parahaemolyticus strains (n=32) were also tested to determine the specificity of the chromogenic agar. Among these strains, 31 did not grow or exhibited other colony morphologies. The mean recovery of V. parahaemolyticus on the chromogenic agar was ~96.4% relative to tryptic soy agar supplemented with 2% NaCl. In conclusion, the new chromogenic agar is an effective medium to detect V. parahaemolyticus and to differentiate it from other vibrios.

Development of a More Sensitive and Specific Chromogenic Agar Medium for the Detection of Vibrio parahaemolyticus and Other Vibrio Species

Detection and isolation of clinically relevant Vibrio species require selective and differential culture media. This study evaluated the ability of a new chromogenic medium to detect and identify V. parahaemolyticus and other related species. The new medium was found to have better sensitivity and specificity than the conventional medium.

Tespiti için daha duyarlı ve özgül Chromogenic Agar Orta Gelişimi<em&gt; Vibrio parahaemolyticus</em&gt; Ve Diğer<em&gt; Vibrio</em&gt; Türler

Foodborne infections in the US caused by Vibrio species have shown an upward trend. In the genus Vibrio, V. parahaemolyticus is responsible for the ...

Measurement of In Vitro Integration Activity of HIV-1 Preintegration Complexes

HIV-1 envelope proteins engage cognate receptors on the target cell surface, which leads to viral-cell membrane fusion followed by the release of the viral capsid (CA) core into the cytoplasm. Subsequently, the viral Reverse Transcriptase (RT), as part of a namesake nucleoprotein complex termed the Reverse Transcription Complex (RTC), converts the viral single-stranded RNA genome into a double-stranded DNA copy (vDNA). This leads to the biogenesis of another nucleoprotein complex, termed the pre-integration complex (PIC), composed of the vDNA and associated virus proteins and host factors. The PIC-associated viral integrase (IN) orchestrates the integration of the vDNA into the host chromosomal DNA in a temporally and spatially regulated two-step process. First, the IN processes the 3&#39; ends of the vDNA in the cytoplasm and, second, after the PIC traffics to the nucleus, it mediates integration of the processed vDNA into the chromosomal DNA. The PICs isolated from target cells acutely infected with HIV-1 are functional in vitro, as they are competent to integrate the associated vDNA into an exogenously added heterologous target DNA. Such PIC-based in vitro integration assays have significantly contributed to delineating the mechanistic details of retroviral integration and to discovering IN inhibitors. In this report, we elaborate upon an updated HIV-1 PIC assay that employs a nested real-time quantitative Polymerase Chain Reaction (qPCR)-based strategy for measuring the in vitro integration activity of isolated native PICs.

Measurement of In Vitro Integration Activity of HIV-1 Preintegration Complexes

This report describes an in vitro assay for measuring the human immunodeficiency virus type 1 (HIV-1) preintegration complex (PIC)-associated integration activity in the cytoplasmic extracts of acutely infected cells. The integration of PIC-associated HIV-1 DNA into heterologous target DNA is quantified by using a nested real-time polymerase chain reaction strategy.

Ölçümü<em&gt; İn Vitro</em&gt; HIV-1 Preintegration Kompleksleri Entegrasyon Etkinliği

HIV-1 envelope proteins engage cognate receptors on the target cell surface, which leads to viral-cell membrane fusion followed by the release of the ...

Highly Multiplexed, Super-resolution Imaging of T Cells Using madSTORM

Imaging heterogeneous cellular structures using single molecule localization microscopy has been hindered by inadequate localization precision and multiplexing ability. Using fluorescent nano-diamond fiducial markers, we describe the drift correction and alignment procedures required to obtain high precision in single molecule localization microscopy. In addition, a new multiplexing strategy, madSTORM, is described in which multiple molecules are targeted in the same cell using sequential binding and elution of fluorescent antibodies. madSTORM is demonstrated on an activated T cell to visualize the locations of different components within a membrane-bound, multi-protein structure called the T cell receptor microcluster. In addition, application of madSTORM as a general tool for visualization of multi-protein structures is discussed.

We demonstrate a method to image multiple molecules within heterogeneous nano-structures at single molecule accuracy using sequential binding and elution of fluorescently labeled antibodies.