Biz bu yazının grafik tasarım ve fotoğraf için David R. Rodriguez, MA teşekkür etmek istiyorum. Bu çalışma UTHSCSA Sitometrisi Çekirdek imkan ve UTHSCSA Gelişmiş Nükleik Asitler Çekirdek Tesisi GCCRI, NIH / NIA (5R21AG033339) ve Kanser Merkezi Destek Hibe (P30CA054174) fon tarafından desteklenmiştir.

Yazarlar herhangi bir mali çıkarlarını beyan.

Burada tarif edilen in vivo mutajenezi, ilk deney Kohler et al. 18 Bu model, lacI genini taşıyan bir raportör λ faj vektörü kullanır tarafından oluşturulan LacI transgenik fare modeline dayanır. Vektör bulaşıcı faj parçacıkları halinde nispeten basit bir iyileşme ve daha sonraki ambalajlama için izin komşu iki cos siteleri, E. enfekte etmek için kullanılır coli. Bir mavi plak faj ile enfekte edilmiş E. tarafından ...

Çok dokusunda, farklılaşmış hücreler sınırlı bir yaşam süresi vardır. Fonksiyonel bütünlüğünü korumak için, uzun ömürlü, dokuya özel kök hücreler sürekli olarak da söz konusu doku işlevi için gerekli olan tam olarak farklılaşmış hücrelere neden progenitör hücreler üretir. Kök hücreler aynı zamanda kendini yenileme olarak adlandırılan bir süreçte kendi bölmesini doldurmak. Böylece, kök hücreler nedenle içeri ikamet dokusunun fonksiyonel bütünlüğünün korunmasından sorumlu olan, bunların hasarlı DNA&#39;yı duygusu ve potansiyel onarmak için sağlam mekanizmalar ile donatılmış olması zorunludur. Değilse, onların soyu ile kalıtsal olabilir çoklu genomik (zararlı) tedirginlikler, edinebilirler. Kök hücreler bir organizmanın ömrü boyunca kendi genomunu güvenli-guard nasıl anlamak önemli bir sorudur ve genomik istikrarsızlık kanser ve (1,2 gözden) diğer bazı yaşa bağlı hastalıklar ile bağlantılı neden anlamamıza yardımcı olabilir. <p class = &quot;jove_content&quot;&gt; kök hücre veya erken projenitör hücre popülasyonlarının düzeyinde bir doku genomik bütünlüğünü kontrol / hücre ölümü, yaşlanma ya da farklılaşma ile kök hücrelerinin kusurlu (veya progenitör) ortadan kaldırılması, ve her iki tarafından ya da etkili bir tamir ile elde edilebilir hasarlı DNA. Son çalışmalar, bu nadir popülasyonlarda 3-6 doğrudan DNA onarımı belirli türde ölçmek mümkün olduğunu göstermiştir. Bu, örneğin, hematopoietik sistem içinde, çift iplikli DNA sonları (NHEJ), ikincisi daha düşük aslına uygunluk onarım işlemi olmak ve böylece yapma riski birleştirme, homolog rekombinasyon (HR) ya da homolog olmayan sonunda tamir edilebilir olduğu bulunmuştur hataları. Hem hematopoetik kök hücre (HSC) 4,5 olarak kullanılmaktadır, ancak, farelerde erken ataları hücrelerin HR 4 kullanmak ise o HKH&#39;lerin ağırlıklı NHEJ görünüyor. Benzer bir gözlem cilt 6 kök hücreleri için yapıldı. İlginç bir şekilde, insan HSC İK değil, NHEJ,çift ​​iplikli sonları 3 için tercih tamir mekanizması gibi görünüyor. İki tür arasındaki bu işlevsel fark gerçek ya da sadece bir teknolojik ya da deneysel farkı temsil olsun görülecektir. Hasarlı DNA tamir Bir kök hücrenin repertuarı, baz eksizyon tamiri (BER), nükleotid eksizyon tamir (NER) ve uyumsuzluğu onarım (MMR) gibi diğer DNA onarım mekanizmaları dahil etmek olasıdır. DNA hasarı bu tür NHEJ veya İK tarafından tamir edilemez; MMR düzeltmeleri baz baz uyumsuzlukları ve ekleme / silme while döngüleri BER ve NER, tek sarmallı DNA tek veya birden fazla baz çifti lezyonların tamiri için sorumludur. Bu kavramı desteklemek HSC bölme 7-9, bu yolların ve anormalliklerin birinde değişiklikler arasında bir bağlantı gösteren hematopoietik sistemi yanı sıra, miyelodisplastik sendrom 10-16 kaynaklanan bir hastalığa yakalanma riski birçok çalışmalarHSC ve hastalık ilerledikçe 17 genomik instabilite artan ile ilişkilidir. Henüz itibariyle, doğrudan HKH&#39;lerin BER, NER ve MMR ölçümleri rapor edilmemiştir. Mekanik bir düzeyde doku bütünlüğünü kontrol çeşitli işlemleri açıklık ek olarak, bu işlemlerin biri sapmalarını sonuçları genetik karşı, normal olarak, örneğin, test edilebilir, böylece mutasyona uğramış DNA seviyesini ölçmek mümkün zorunludur mühendislik kök hücreleri veya genç, karşı eski içinde. Bununla birlikte, ilgili bir tahlilin geliştirilmesi için dokuya özel kök hücrelerin yetersizliği ve &quot;stemness&quot; korur kültür koşulları eksikliği zordur. Ayrıca, bu tür bir deney Çevresel ve genetik manipülasyonlara iyileştirilebilir olmalıdır. Bu sınırlamalar ve gereksinimlerine Muhtemel bir çözüm, özellikle DNA mutasyonları tespit etmek için tasarlanmıştır fare modelleri kullanılmasıdır. Mulmutasyon tespiti için tiplemesine transgenik fare modelleri geliştirilmiştir. Örneğin, transgenik fareler, LacI 18 LacI gen Lac operatörün bastırıcı kodlayan ve mutasyon muhabir olarak hizmet ettiği LacI raportör sistemi kodlayan bir geri kazanılabilir λ faj vektörü taşır. LacI geninin mutasyon üzerine, Lac operatör etkinleştirilir ve β-galaktosidaz üretilir. β-galaktosidaz böler mavi döner kromojenik alt-tabaka X-gal (5-bromo-4-kloro-e-indolil-β-D-galaktopiranosid). LacI vektörü yan cos siteleri lambda faj protein ve E, daha sonraki enfeksiyonlar ile kolayca giderilmesini sağlar coli. E. inkübe edildikten sonra, enfekte coli X-gal alt tabakayı içeren agaroz, plaklar attı olabilir. Net plaklar olmayan mutantlar liman iken mavi plaklar, Lac-I fajının taşıyan bir farazi mutant içerir. Inci arasında mavi plakların frekansı (e açık olanlar) DNA ekstre edilmiş orijinal hücre popülasyonunda mutant frekansı gösterir. Ayrıca, LacI hedef barındıran λ fajlar, nispeten yüksek verimli analizi için PCR teknikleri kullanılarak dizilenebilir. Birden mutant LacI genleri Dizmek da spesifik DNA onarım yollarındaki olası eksiklikler veya belirli genotoksik olaylara işaret edebilir mutasyon spektrumu hakkında önemli bilgiler ortaya koyacaktır. LacI transgenik sistemi, çok sayıda laboratuarlar 19 standartlaştırıldı ve ayıraçlar piyasada mevcuttur. LacI sistemin bir dezavantajı, büyük silinti ve yeniden düzenlemeleri tespit etmek için sınırlı bir yeteneği vardır, bu nedenle, metafaz yayılır diğer yöntemler, örneğin çok renkli FISH bu eksikliği iltifat için kullanılması gerekmektedir. LacI fare modeli λ faj vektörü içinde, çok daha küçük bir gen, CII orada, Mutasyon analizi için kullanılabilir. Boyutu ve mutantlar seçilebilir olması bu LacI gen analizi daha az emek-yoğun ve daha ucuz deney 20 hale getirir. Bir kromojenik alt tabaka 22-25 bir fenotipik yanıt oluşturmak amino asit kalıntılarının bir anlaşılması olduğu Bununla birlikte, LacI gen daha kapsamlı mutagenez 21 ve mutasyon genin hassasiyeti için çalışılmıştır, iyi karakterize edilmiştir. Mutasyon tespiti için diğer fare modelleri ΦX174 ya da LacZ transgenlerin kullanımı bulunmaktadır. T → G: Orijinal A ΦX174 transgenik fare modeli, C reversiyon mutasyon deneyi 26 veya baz çifti değiştirmelerin bir spektrum algılama, LacI modele göre daha az maliyetli bir sistem temsil verir ileri mutasyon deneyi 27. Bununla birlikte, ön deneyde mutasyon ekran önemsiz ve mutasyon spec değilΦX174 transgen TRUM olarak LacI bu kadar iyi karakterize değildir. LacZ transgenini taşıyan fare modellerinde, LacZ raportör mutasyon E. kullanılarak elde edilir galaktoz ve 28 galaktoz içeren ortama duyarlı olan coli konakçı hücreler. Bu sistemin bir dezavantajı, LacZ hedefin iyileşme de E. ligasyonu ve elektroporasyon takiben sınırlandırma endonükleaz sindirim içerir olmasıdır coli böylece zor hücreleri küçük sayılar için sisteme adapte yapma, ev sahipliği yapıyor. Bu kök / progenitör hücre popülasyonları ile çalışmak için mutlak bir gerekliliktir (bir zaman daha fareler ile başlayabilir) olmamasına rağmen hücreleri çok sayıda (örneğin, milyonlarca ya da daha fazla) gerekiyorsa, hızlı pratik ve maliyet engelleyici olacaktır. Hassas bir mutasyon muhabir sağlarken, aynı zamanda, LacZ nispeten büyük boyutlu, hantal ve DNA sekans analizi ve unsurlar için daha maliyetlidirmutasyon spektrumları ination. Bu modelin önemli bir avantajı ise, geniş eksiltmeler ve ilaveler tespit etme yeteneği, hem de kromozomal yeniden düzenlemeleri olan. LacI, ΦX174 ve LacZ transgenik fare modellerinde tüm hücreler raportör sistemi taşımak için, bu fare modellerinin herhangi biri gibi uzun süre güvenilir bir şekilde hasat edilebilir, kök ve projenitör hücreleri dahil olmak üzere, ilgi konusu her bir hücre tipinde mutagenez ölçmek için kullanılabilir ve yeterli sayıda. Biz LacI fare modeli ve LacI mutasyon deneyi ile geniş bir deneyim oldu çünkü, biz hematopoetik kök ve progenitör toplumlarda mutagenez analizi için bu sistemi daha sürdürmeye karar verdi. Hematopoetik doku Lin derece nadir nüfus olarak tanımlanabilir olan uzun vadeli repopulating kök hücreleri de dahil olmak üzere bireysel bileşenler, hücre yüzeyi fenotip açısından iyi karakterize olduğunu - IL7R <sup&gt; - Sca-1 + cKit + + (LSK&#39;ya) / Flk2 - CD150 + CD48 - hücreleri 29. . DNA onarım eğitim söz konusu olduğunda hücreler hala HKH&#39;lerin için iyi temsilcileri olan ve en ilkel taahhüt miyeloid progenitör (CMP) nüfus önemli derecede farklı - Mohrin ark 4 LSK/Flk2 biraz daha büyük nüfus olduğunu göstermiştir. Ayrıca, zaman HSC bakımından zenginleştirilmiş LSK (Flk-2 + ve Flk-2 -) - IL7R - hücreler, Lin karşılaştırıldı Sca-1-cKit + + (LS-K progenitor hücreler), önemli bir fark yine yoktu az saf arasında NHEJ yeteneği 5, hücre ile zenginleştirilmiş LSK&#39;ya nüfusu ve progenitör kök hücreler. Bu hücre sayısı son derece zordur, en az 2 x 10 5 hücre Bu mutagenez deneyde, tutarlı ve güvenilir sonuçlar için gerekli olduğu bulunmuştur, çünkü hücreler, - Çalışmamızda LSK (Flk-2 + ve Flk-2) HSC zenginleştirilmiş kullanımıCD150 + CD48 nüfus hatta LSK/Flk2 - -, nüfus (fareler, maliyet ve pratiklik açısından) bir LSK/Flk2 sıralar zaman elde edilmiştir. Başlangıçta Kohler ve ark. 18 tarafından geliştirilen birine dayalı bu protokol, spontan DNA mutant frekans farklılaşmış miyeloid hücrelerin popülasyonları gibi ayrışmamış kemik iliği ve dalak hücreleri LSK&#39;ya hücrelerinde tespit ve tanımlanabilir nasıl ayrıntılı olarak anlatılmaktadır.

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		<col />
		<col />
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	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:252px;">LacI transgenic mice&#160;</td>
			<td style="width:245px;">BioReliance Corporation</td>
			<td style="width:195px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:252px;">RecoverEase DNA Isolation Kit, including the RNace-It ribonuclease cocktail</td>
			<td style="width:245px;">Agilent Technologies (Stratagene)</td>
			<td style="width:195px;">720202</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:252px;">Transpack Packaging Extract, including the orange and blue transpack tubes and the SCS-8 E. coli</td>
			<td style="width:245px;">Agilent Technologies (Stratagene)</td>
			<td style="width:195px;">200221</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">DNA size standards &#8211; lambda ladder</td>
			<td>Bio Rad</td>
			<td>170-3635</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">0.025 mM pore size membranes&#160;</td>
			<td>Fisher (Millipore)</td>
			<td>VSWP 025 00</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">245 mm2 bioassay dishes (trays)&#160;</td>
			<td>Fisher (Corning)</td>
			<td>07-200-600</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NZY broth (powder)</td>
			<td>Fisher (Teknova)</td>
			<td>N1144</td>
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		<tr height="21">
			<td height="21" style="height:21px;">Agar</td>
			<td>Fisher</td>
			<td>BP1423-500</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Agarose</td>
			<td>Fisher</td>
			<td>E-3120-500</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">N, N-dimethylformamide</td>
			<td>Fisher</td>
			<td>AC34843-5000</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">X-gal</td>
			<td>Research Products Intl Corp (RPI)</td>
			<td>B71800-10.0</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Proteinase K</td>
			<td>Roche</td>
			<td>3-115-852</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PCR Extender Taq Polimerase kit</td>
			<td>5 PRIME</td>
			<td>2200500</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;">Agencourt AMPure XP cleanup kit</td>
			<td>Beckman/coulter</td>
			<td>A63880</td>
		</tr>
	</tbody>
</table>

identifying dna mutations in purified hematopoietic stem/progenitor cells

Son yıllarda, çok sıkı bir şekilde genomik instabilite gelişimsel bozukluklar, kanser, ve yaşlanma ile ilişkili olduğu ortaya çıkmıştır. Kök hücreler yaşam boyu doku homeostazını ve onarım sağlamak için sorumlu olduğu göz önüne alındığında, bu kök hücre popülasyonu dokuların genomik bütünlüğünü korumak için önemli olduğunu varsaymak mantıklıdır. Bu nedenle, önemli faiz kök hücre bazlı hastalıkların etyolojisi anlamak amacıyla, genomik kök hücre dürüstlük ve onların soyu üzerinde endojen ve çevresel faktörlerin etkisinin değerlendirilmesinde ortaya çıkmıştır. LacI transgenik fareler, LacI gen mutasyon muhabir olarak hizmet ettiği LacI raportör sistemi kodlayan bir geri kazanılabilir λ faj vektörü taşır. Mutasyona uğramış bir LacI geninin sonucu bu böler mavi çevirerek, bir kromojenik alt tabaka, β-galaktosidaz üretimidir. LacI raportör sistemi gerçekleştirilir istem / progenitor hücreler de dahil olmak üzere ve kolay bir şekilde geri kazanılmış ve daha sonra E. enfekte etmek için kullanılabilir n tüm hücreler, coli. E. inkübe edildikten sonra, enfekte doğru alt tabakayı içeren agaroz coli, plaklar atılır olabilir; açık plaklar vahşi tip liman iken mavi plaklar, bir mutant LacI genini göstermektedir. Plakların (net arasında) mavisi sıklığı DNA elde edildi, orijinal hücre popülasyonunda mutant frekansı gösterir. Mutant LacI genini diziliş gendeki mutasyonlar konumunu ve mutasyon tipini gösterir. LacI transgenik fare modeli, bir in vivo mutajenezi deneyi gibi iyi bilinmektedir. Ayrıca, tahlil için fareler ve ayıraçlar piyasada mevcuttur. Burada bu model kendiliğinden kök hücre zenginleştirilmiş Lin DNA meydana gelen mutasyona uğramış frekansını ölçmek için adapte edilebilir ayrıntılı olarak açıklanmıştır - IL7R - Sca-1 + + + cKit (LSK) hücreleri ve hematopoietik sistemin diğer altgrupları.

<html> In vivo mutajenez tahlil nadir bir olay birçok olaylar arasında (mutant pfus) (Tüm pfus) ölçer. Küçük hücre sayısı ile tahlil gerçekleştirerek, bu sonuç oldukça olumlu-yanlış ve yanlış-negatif sonuçları etkilenir mümkündür. Bu sorunu çözmek için üç farklı hayvanlar hasat fraksiyonlanmamış kemik iliği hücreleri, bir seri seyreltme deney gerçekleştirdi. Biz, 1.4 x 10 6, 7.0 x 10 5 kullanarak bu hayvanların kemik iliğinde 3.5 x 10 5 mutan...

Watch this Scientific Journal Video about Identifying DNA Mutations in Purified Hematopoietic Stem/Progenitor Cells at JoVE.com

Saflaştırılmış Hematopoietik Kök/Progenitör Hücrelerde DNA Mutasyonlarının Belirlenmesi | İmmünoloji ve Enfeksiyon | Video

Identifying DNA Mutations in Purified Hematopoietic Stem/Progenitor Cells

Burada LacI transgenik fare modeli kullanılarak arıtılmış, hematopoietik hücrelerin az sayıda için bir in vivo deneyini tarif mutagenez. LacI gen DNA mutantlarının sıklığı, yer ve tip kendiliğinden ortaya çıkan veya Genotoksinlerin maruz kaldıktan sonra belirlemek için izole edilebilir.

Saf Hematopoetik kök / progenitör hücrelerin DNA mutasyonları belirlenmesi

In recent years, it has become apparent that genomic instability is tightly related to many developmental disorders, cancers, and aging. Given that stem ...

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12.9K Görüntüleme.  UT Health Science Center at San Antonio.  Burada LacI transgenik fare modeli kullanılarak arıtılmış, hematopoietik hücrelerin az sayıda için bir in vivo deneyini tarif mutagenez. LacI gen DNA mutantlarının sıklığı, yer ve tip kendiliğinden ortaya çıkan veya Genotoksinlerin maruz kaldıktan sonra belirlemek için izole edilebilir. 

Video: Identifying DNA Mutations in Purified Hematopoietic Stem/Progenitor Cells

Identifying Dysregulated Genes Induced by Kaposi's Sarcoma-associated Herpesvirus (KSHV)

Currently KS is the most predominant HIV/AIDS related malignancy in Southern Africa and hence the world.1,2 It is characterized as an angioproliferative tumor of vascular endothelial cells and produces rare B cell lymphoproliferative diseases in the form of pleural effusion lymphomas (PEL) and some forms of multicentric Castleman's disease.3-5 Only 1-5% of cells in KS lesions actively support lytic replication of Kaposi's sarcoma-associated herpesvirus (KSHV), the etiological agent associated with KS, and it is clear that cellular factors must interact with viral factors in the process of oncogenesis and tumor progression.6,7 Identifying novel host-factor determinants which contribute to KS pathology is essential for developing prognostic markers for tumor progression and metastasis as well as for developing novel therapeutics for the treatment of KS.8 The accompanying video details the methods we use to identify host cell gene expression programs altered in dermal microvascular endothelial cells (DMVEC) after KSHV infection and in KS tumor tissue.9 Once dysregulated genes are identified by microarray analysis, changes in protein expression are confirmed by immunoblot and dual labeled immunofluorescence. Changes in transcriptional expression of dysregulated genes are confirmed in vitro by quantitative real-time polymerase chain reaction (qRT-PCR). Validation of in vitro findings using archival KS tumor tissue is also performed by dual labeled immunochemistry and tissue microarrays.8,10 Our approach to identifying dysregulated genes in the KS tumor tissue microenvironment will allow the development of in vitro and subsequently in vivo model systems for discovery and evaluation of potential novel therapeutic for the treatment of KS.

Identifying Dysregulated Genes Induced by Kaposi&#039;s Sarcoma-associated Herpesvirus KSHV

Host cell factors play a critical role in the establishment and maintenance of Kaposi's sarcoma (KS). We outline methods to identify host cell factors altered in KSHV-infected DMVEC cells, and in KS tumor tissue. Cellular genes altered by virus will serve as potential target(s) for novel therapeutics.

Kaposi sarkomu ile ilişkili Herpes (KSHV) Yol Açtığı düzensiz Genler belirlenmesi

Currently KS is the most predominant HIV/AIDS related malignancy in Southern Africa and hence the world.1,2 It is characterized as an angioproliferative ...

İmmünoloji ve Enfeksiyon

Induction and Assessment of Class Switch Recombination in Purified Murine B Cells

Humoral immunity is the branch of the immune system maintained by B cells and mediated through the secretion of antibodies. Upon B cell activation, the immunoglobulin locus undergoes a series of genetic modifications to alter the binding capacity and effector function of secreted antibodies. This process is highlighted by a genomic recombination event known as class switch recombination (CSR) in which the default IgM antibody isotype is substituted for one of IgG, IgA, or IgE. Each isotype possesses distinct effector functions thereby making CSR crucial to the maintenance of immunity. Diversification of the immunoglobulin locus is mediated by the enzyme activation-induced cytidine deaminase (AID). A schematic video describing this process in detail is available online (http://video.med.utoronto.ca/videoprojects/immunology/aam.html). AID's activity and the CSR pathway are commonly studied in the assessment of B cell function and humoral immunity in mice. The protocol outlined in this report presents a method of B cell isolation from murine spleens and subsequent stimulation with bacterial lipopolysaccharide (LPS) to induce class switching to IgG3 (for other antibody isotypes see Table 1). In addition, the fluorescent cell staining dye Carboxyfluorescein succinimidyl ester (CFSE) is used to monitor cell division of stimulated cells, a process crucial to isotype switching 1, 2. The regulation of AID and the mechanism by which CSR occurs are still unclear and thus in vitro class switch assays provide a reliable method for testing these processes in various mouse models. These assays have been previously used in the context of gene deficiency using knockout mice 3. Furthermore, in vitro switching of B cells can be preceded by viral transduction to modulate gene expression by RNA knockdown or transgene expression 4-6. The data from these types of experiments have impacted our understanding of AID activity, resolution of the CSR reaction, and antibody-mediated immunity in the mouse.

Following antigen exposure, subpopulations of activated B cells undergo a process known as class switch recombination (CSR) to produce antibody isotypes with distinct effector functions. The protocol outlined in this report explains how CSR can be induced and analyzed in vitro for the purposes of studying B cell function.

Sınıf Anahtarı Rekombinasyon murin B Hücreleri Saf İndüksiyon ve Değerlendirme

Humoral immunity is the branch of the immune system maintained by B cells and mediated through the secretion of antibodies. Upon B cell activation, the ...

Colony Forming Cell (CFC) Assay for Human Hematopoietic Cells

Human hematopoietic stem/progenitor cells are usually obtained from bone marrow, cord blood, or peripheral blood and are used to study hematopoiesis and leukemogenesis. They have the capacity to differentiate into lymphoid and myeloid lineages. The colony forming cell (CFC) assay is used to study the proliferation and differentiation pattern of hematopoietic progenitors by their ability to form colonies in a semisolid medium. The number and the morphology of the colonies formed by a fixed number of input cells provide preliminary information about the ability of progenitors to differentiate and proliferate. Cells can be harvested from individual colonies or from the whole plate to further assess their numbers and differentiation states using flow cytometry and morphologic evaluation of Giemsa-stained slides. This assay is useful for assessing myeloid but not lymphoid differentiation. The term myeloid in this context is used in its wider sense to encompass granulocytic, monocytic, erythroid, and megakaryocytic lineages.

We have used this assay to assess the effects of oncogenes on the differentiation of primary human CD34+ cells derived from peripheral blood. For this purpose cells are transduced with either control retroviral construct or a construct expressing the oncogene of interest, in this case NUP98-HOXA9. We employ a commonly used retroviral vector, MSCV-IRES-GFP, that expresses a bicistronic mRNA that produces the gene of interest and a GFP marker. Cells are pre-activated by growing in the presence of cytokines for two days prior to retroviral transduction. After another two days, GFP+ cells are isolated by fluorescence-activated cell sorting (FACS) and mixed with a methylcellulose-containing semisolid medium supplemented with cytokines and incubated till colonies appear on the surface, typically 14 days. The number and morphology of the colonies are documented. Cells are then removed from the plates, washed, counted, and subjected to flow cytometry and morphologic examination. Flow cytometry with antibodies specific to the cell surface markers expressed during hematopoiesis provides information about lineage and maturation stage. Morphological studies of individual cells under a microscope after Wright- Giemsa staining provide further information with regard to lineage and maturation. Comparison of cells transduced with control empty vector to those transduced with an oncogene reveals the effects of the oncogene on hematopoietic differentiation.

Colony Forming Cell CFC Assay for Human Hematopoietic Cells

The colony forming cell (CFC) assay is an in vitro assay in which hematopoietic progenitors form colonies in a semi-solid medium. A combination of colony morphology, cell morphology, and flow cytometry are used to assess the ability of the progenitors to proliferate and differentiate along the different hematopoietic lineages.

Koloni Oluşturan İnsan Hematopoetik Hücreler Hücre (CFC) Testi

Human hematopoietic stem/progenitor cells are usually obtained from bone marrow, cord blood, or peripheral blood and are used to study hematopoiesis and ...

Seven Steps to Stellate Cells

Hepatic stellate cells are liver-resident cells of star-like morphology and are located in the space of Disse between liver sinusoidal endothelial cells and hepatocytes1,2. Stellate cells are derived from bone marrow precursors and store up to 80% of the total body vitamin A1, 2. Upon activation, stellate cells differentiate into myofibroblasts to produce extracellular matrix, thus contributing to liver fibrosis3. Based on their ability to contract, myofibroblastic stellate cells can regulate the vascular tone associated with portal hypertension4. Recently, we demonstrated that hepatic stellate cells are potent antigen presenting cells and can activate NKT cells as well as conventional T lymphocytes5. 

 Here we present a method for the efficient preparation of hepatic stellate cells from mouse liver. Due to their perisinusoidal localization, the isolation of hepatic stellate cells is a multi-step process. In order to render stellate cells accessible to isolation from the space of Disse, mouse livers are perfused in situ with the digestive enzymes Pronase E and Collagenase P. Following perfusion, the liver tissue is subjected to additional enzymatic treatment with Pronase E and Collagenase P in vitro. Subsequently, the method takes advantage of the massive amount of vitamin A-storing lipid droplets in hepatic stellate cells. This feature allows the separation of stellate cells from other hepatic cell types by centrifugation on an 8% Nycodenz gradient. The protocol described here yields a highly pure and homogenous population of stellate cells. Purity of preparations can be assessed by staining for the marker molecule glial fibrillary acidic protein (GFAP), prior to analysis by fluorescence microscopy or flow cytometry. Further, light microscopy reveals the unique appearance of star-shaped hepatic stellate cells that harbor high amounts of lipid droplets. 


 Taken together, we present a detailed protocol for the efficient isolation of hepatic stellate cells, including representative images of their morphological appearance and GFAP expression that help to define the stellate cell entity.

Here we describe a method for the isolation of hepatic stellate cells from mouse liver. For stellate cell purification, mouse livers are digested in situ and in vitro by pronase-collagenase treatment prior to density gradient centrifugation. This technique yields highly pure hepatic stellate cells.

Hücreler stellat Yedi Adımda

Hepatic stellate cells are liver-resident  cells of star-like morphology and are located in the space of Disse between  liver sinusoidal endothelial cells ...

Generation of Multivirus-specific T Cells to Prevent/treat Viral Infections after Allogeneic Hematopoietic Stem Cell Transplant

Viral infections cause morbidity and mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. We and others have successfully generated and infused T-cells specific for Epstein Barr virus (EBV), cytomegalovirus (CMV) and Adenovirus (Adv) using monocytes and EBV-transformed lymphoblastoid cell (EBV-LCL) gene-modified with an adenovirus vector as antigen presenting cells (APCs). As few as 2x105/kg trivirus-specific cytotoxic T lymphocytes (CTL) proliferated by several logs after infusion and appeared to prevent and treat even severe viral disease resistant to other available therapies. The broader implementation of this encouraging approach is limited by high production costs, complexity of manufacture and the prolonged time (4-6 weeks for EBV-LCL generation, and 4-8 weeks for CTL manufacture &#x2013; total 10-14 weeks) for preparation. To overcome these limitations we have developed a new, GMP-compliant CTL production protocol. First, in place of adenovectors to stimulate T-cells we use dendritic cells (DCs) nucleofected with DNA plasmids encoding LMP2, EBNA1 and BZLF1 (EBV), Hexon and Penton (Adv), and pp65 and IE1 (CMV) as antigen-presenting cells. These APCs reactivate T cells specific for all the stimulating antigens. Second, culture of activated T-cells in the presence of IL-4 (1,000U/ml) and IL-7 (10ng/ml) increases and sustains the repertoire and frequency of specific T cells in our lines. Third, we have used a new, gas permeable culture device (G-Rex) that promotes the expansion and survival of large cell numbers after a single stimulation, thus removing the requirement for EBV-LCLs and reducing technician intervention. By implementing these changes we can now produce multispecific CTL targeting EBV, CMV, and Adv at a cost per 106 cells that is reduced by &gt;90%, and in just 10 days rather than 10 weeks using an approach that may be extended to additional protective viral antigens. Our FDA-approved approach should be of value for prophylactic and treatment applications for high risk allogeneic HSCT recipients.

A rapid, simple and cost-effective protocol for the generation of donor-derived multivirus-specific CTLs (rCTL) for infusion to allogeneic hematopoietic stem cell transplant (HSCT) recipients at risk of developing CMV, Adv or EBV infections. This manufacturing process is GMP-compliant and should ensure the broader implementation of T-cell immunotherapy beyond specialized centers.

Multivirus-spesifik T hücrelerinin üretilmesi Allojenik Hematopoetik Kök Hücre Nakli sonra Viral Enfeksiyonlar önleme / tedavi etmek için

Viral infections cause morbidity and mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. We and others have successfully ...

Following Cell-fate in E. coli After Infection by Phage Lambda

The system comprising bacteriophage (phage) lambda and the bacterium E. coli has long served as a paradigm for cell-fate determination1,2. Following the simultaneous infection of the cell by a number of phages, one of two pathways is chosen: lytic (virulent) or lysogenic (dormant)3,4. We recently developed a method for fluorescently labeling individual phages, and were able to examine the post-infection decision in real-time under the microscope, at the level of individual phages and cells5. Here, we describe the full procedure for performing the infection experiments described in our earlier work5. This includes the creation of fluorescent phages, infection of the cells, imaging under the microscope and data analysis. The fluorescent phage is a "hybrid", co-expressing wild- type and YFP-fusion versions of the capsid gpD protein. A crude phage lysate is first obtained by inducing a lysogen of the gpD-EYFP (Enhanced Yellow Fluorescent Protein) phage, harboring a plasmid expressing wild type gpD. A series of purification steps are then performed, followed by DAPI-labeling and imaging under the microscope. This is done in order to verify the uniformity, DNA packaging efficiency, fluorescence signal and structural stability of the phage stock. The initial adsorption of phages to bacteria is performed on ice, then followed by a short incubation at 35&deg;C to trigger viral DNA injection6. The phage/bacteria mixture is then moved to the surface of a thin nutrient agar slab, covered with a coverslip and imaged under an epifluorescence microscope. The post-infection process is followed for 4 hr, at 10 min interval. Multiple stage positions are tracked such that ~100 cell infections can be traced in a single experiment. At each position and time point, images are acquired in the phase-contrast and red and green fluorescent channels. The phase-contrast image is used later for automated cell recognition while the fluorescent channels are used to characterize the infection outcome: production of new fluorescent phages (green) followed by cell lysis, or expression of lysogeny factors (red) followed by resumed cell growth and division. The acquired time-lapse movies are processed using a combination of manual and automated methods. Data analysis results in the identification of infection parameters for each infection event (e.g. number and positions of infecting phages) as well as infection outcome (lysis/lysogeny). Additional parameters can be extracted if desired.

Following Cell-fate in E. coli After Infection by Phage Lambda

This article describes the procedure for preparing a fluorescently-labeled version of bacteriophage lambda, infection of E. coli bacteria, following the infection outcome under the microscope, and analysis of infection results.

Hücre-kaderi ardından<em&gt; E. coli</em&gt; Faj Lambda tarafından Enfeksiyon Sonrası

The system comprising bacteriophage (phage) lambda and the bacterium E. coli has long served as a paradigm for cell-fate determination1,2. Following the ...

Establishment of an In vitro System to Study Intracellular Behavior of Candida glabrata in Human THP-1 Macrophages

A cell culture model system, if a close mimic of host environmental conditions, can serve as an inexpensive, reproducible and easily manipulatable alternative to animal model systems for the study of a specific step of microbial pathogen infection. A human monocytic cell line THP-1 which, upon phorbol ester treatment, is differentiated into macrophages, has previously been used to study virulence strategies of many intracellular pathogens including Mycobacterium tuberculosis. Here, we discuss a protocol to enact an in vitro cell culture model system using THP-1 macrophages to delineate the interaction of an opportunistic human yeast pathogen Candida glabrata with host phagocytic cells. This model system is simple, fast, amenable to high-throughput mutant screens, and requires no sophisticated equipment. A typical THP-1 macrophage infection experiment takes approximately 24 hr with an additional 24-48 hr to allow recovered intracellular yeast to grow on rich medium for colony forming unit-based viability analysis. Like other in vitro model systems, a possible limitation of this approach is difficulty in extrapolating the results obtained to a highly complex immune cell circuitry existing in the human host. However, despite this, the current protocol is very useful to elucidate the strategies that a fungal pathogen may employ to evade/counteract antimicrobial response and survive, adapt, and proliferate in the nutrient-poor environment of host immune cells.

Establishment of an In vitro System to Study Intracellular Behavior of Candida glabrata in Human THP-1 Macrophages

The current article outlines a protocol to establish an in vitro cell culture model system to study the interaction of a facultative intracellular human fungal pathogen Candida glabrata with human macrophages which will be a useful tool to advance our knowledge of fungal virulence mechanisms.

A cell culture model system, if a close mimic of host environmental conditions, can serve as an inexpensive, reproducible and easily manipulatable ...

Systemic Injection of Neural Stem/Progenitor Cells in Mice with Chronic EAE

Neural stem/precursor cells (NPCs) are a promising stem cell source for transplantation approaches aiming at brain repair or restoration in regenerative neurology. This directive has arisen from the extensive evidence that brain repair is achieved after focal or systemic NPC transplantation in several preclinical models of neurological diseases.
These experimental data have identified the cell delivery route as one of the main hurdles of restorative stem cell therapies for brain diseases that requires urgent assessment. Intraparenchymal stem cell grafting represents a logical approach to those pathologies characterized by isolated and accessible brain lesions such as spinal cord injuries and Parkinson's disease. Unfortunately, this principle is poorly applicable to conditions characterized by a multifocal, inflammatory and disseminated (both in time and space) nature, including multiple sclerosis (MS). As such, brain targeting by systemic NPC delivery has become a low invasive and therapeutically efficacious protocol to deliver cells to the brain and spinal cord of rodents and nonhuman primates affected by experimental chronic inflammatory damage of the central nervous system (CNS).
This alternative method of cell delivery relies on the NPC pathotropism, specifically their innate capacity to (i) sense the environment via functional cell adhesion molecules and inflammatory cytokine and chemokine receptors; (ii) cross the leaking anatomical barriers after intravenous (i.v.) or intracerebroventricular (i.c.v.) injection; (iii) accumulate at the level of multiple perivascular site(s) of inflammatory brain and spinal cord damage; and (i.v.) exert remarkable tissue trophic and immune regulatory effects onto different host target cells in vivo.
Here we describe the methods that we have developed for the i.v. and i.c.v. delivery of syngeneic NPCs in mice with experimental autoimmune encephalomyelitis (EAE), as model of chronic CNS inflammatory demyelination, and envisage the systemic stem cell delivery as a valuable technique for the selective targeting of the inflamed brain in regenerative neurology.

The transplantation of neural stem/progenitor cells (NPCs) holds great promises in regenerative neurology. The systemic delivery of NPCs has turned into effective, low invasive, and therapeutically very efficacious protocol to deliver stem cells in the brain and spinal cord of rodents and nonhuman primates affected by experimental chronic inflammatory damage of the central nervous system.

Kronik EAE ile Fare nöral kök / progenitör hücrelerinin sistemik enjeksiyonundan

Neural stem/precursor cells (NPCs) are a promising stem cell source for transplantation approaches aiming at brain repair or restoration in regenerative ...

Visualizing Protein-DNA Interactions in Live Bacterial Cells Using Photoactivated Single-molecule Tracking

Protein-DNA interactions are at the heart of many fundamental cellular processes. For example, DNA replication, transcription, repair, and chromosome organization are governed by DNA-binding proteins that recognize specific DNA structures or sequences. In vitro experiments have helped to generate detailed models for the function of many types of DNA-binding proteins, yet, the exact mechanisms of these processes and their organization in the complex environment of the living cell remain far less understood. We recently introduced a method for quantifying DNA-repair activities in live Escherichia coli cells using Photoactivated Localization Microscopy (PALM) combined with single-molecule tracking. Our general approach identifies individual DNA-binding events by the change in the mobility of a single protein upon association with the chromosome. The fraction of bound molecules provides a direct quantitative measure for the protein activity and abundance of substrates or binding sites at the single-cell level. Here, we describe the concept of the method and demonstrate sample preparation, data acquisition, and data analysis procedures.

Photoactivated localization microscopy (PALM) combined with single-molecule tracking allows direct observation and quantification of protein-DNA interactions in live Escherichia coli cells.

Fotoaktive Tek molekül Takip Kullanma Canlı Bakteriyel Hücrelerde Protein-DNA Etkileşimleri görselleştirme

Protein-DNA interactions are at the heart of many fundamental cellular processes. For example, DNA replication, transcription, repair, and chromosome ...

Assessing the Development of Murine Plasmacytoid Dendritic Cells in Peyer's Patches Using Adoptive Transfer of Hematopoietic Progenitors

This protocol details a method to analyze the ability of purified hematopoietic progenitors to generate plasmacytoid dendritic cells (pDC) in intestinal Peyer&#39;s patch (PP). Common dendritic cell progenitors (CDPs, lin- c-kitlo CD115+ Flt3+) were purified from the bone marrow of C57BL6 mice by FACS and transferred to recipient mice that lack a significant pDC population in PP; in this case, Ifnar-/- mice were used as the transfer recipients. In some mice, overexpression of the dendritic cell growth factor Flt3 ligand (Flt3L) was enforced prior to adoptive transfer of CDPs, using hydrodynamic gene transfer (HGT) of Flt3L-encoding plasmid. Flt3L overexpression expands DC populations originating from transferred (or endogenous) hematopoietic progenitors. At 7-10 days after progenitor transfer, pDCs that arise from the adoptively transferred progenitors were distinguished from recipient cells on the basis of CD45 marker expression, with pDCs from transferred CDPs being CD45.1+ and recipients being CD45.2+. The ability of transferred CDPs to contribute to the pDC population in PP and to respond to Flt3L was evaluated by flow cytometry of PP single cell suspensions from recipient mice. This method may be used to test whether other progenitor populations are capable of generating PP pDCs. In addition, this approach could be used to examine the role of factors that are predicted to affect pDC development in PP, by transferring progenitor subsets with an appropriate knockdown, knockout or overexpression of the putative developmental factor and/or by manipulating circulating cytokines via HGT. This method may also allow analysis of how PP pDCs affect the frequency or function of other immune subsets in PPs. A unique feature of this method is the use of Ifnar-/- mice, which show severely depleted PP pDCs relative to wild type animals, thus allowing reconstitution of PP pDCs in the absence of confounding effects from lethal irradiation.

Assessing the Development of Murine Plasmacytoid Dendritic Cells in Peyer&#039;s Patches Using Adoptive Transfer of Hematopoietic Progenitors

This protocol describes experimental procedures to assess the differentiation of plasmacytoid dendritic cells in Peyer&#8217;s patch from common dendritic cell progenitors, using techniques involving FACS-mediated cell isolation, hydrodynamic gene transfer, and flow analysis of immune subsets in Peyer&#8217;s patch.

Hematopoetik progenitörlerin Evlatlık Transferi kullanarak Peter Parçacıklannda Murin plazmasitoid dendritik hücreleri Gelişimini değerlendirilmesi

This protocol details a method to analyze the ability of purified hematopoietic progenitors to generate plasmacytoid dendritic cells (pDC) in intestinal ...

Methods Article

Saf Hematopoetik kök / progenitör hücrelerin DNA mutasyonları belirlenmesi