The authors would like to thank Mark Bishop, Mathew Zverev, Victoria Marsh-Durban, Adam Blackwood and Sylvie Robine. This work was funded by a programme grant from Cancer Research UK.

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The authors have nothing to disclose.

Genler ve hücrelerin fonksiyonunu incelemek için koşullu CRE-LOX transgenik fareler kullanılarak yaygın olarak kullanılan bir yöntemdir. Bu modeller belirlemek ve tanımlamak kök hücreleri 2,4-6 ve hastalık 25 rollerini anlamak için bağırsaklarda büyük bir başarı ile kullanılmaktadır. Tam bu modeller yararlanmak için doğru yorumlanmalıdır verileri sağlamak için sistemin kapsamlı bir karakterizasyonu gerektirir. Bu sistemlerin tam anlaşılması nedeniyle genleri nadiren yalnız hücre tipi veya konumu, biyolojik bilgi ve Cre ifadesini uyarmak için kullanılan sistemlerin verimsizlik eksikliği özgü olmasının elde etmek zordur. Burada açıklanan yöntemler deneysel tasarım ve mevcut bilginin uygulanması yoluyla bu sorunları aşmak nasıl gösterilmektedir. Burada sunulan genel ve muri araştıran herhangi araştırma için istismar edilebilir teknikler belirli bir araştırma soruyu cevaplamak için bu yöntemleri kullanmasına rağmenne bağırsak. Bağırsak Doku Hazırlanması Sağlam sonuçlar sağlamaya yönelik önemli bir adım kesinlikle uyulması zamanında bir şekilde ve tespit protokollerinde işlenmesi gereken doku hasat ve işleme. Hemen hemen tüm önemli konular aşağı doku kuruma ve / veya eksik fiksasyonu ile ilişkili eserler isnat edilebilir. Zamanlama doku mimarisi ve / veya nükleik asitlerin ve proteinlerin bozulmasını önlemek için çok önemlidir. Eksik veya overzealous tespit histokimyasal çözünürlük kaybına neden olabilir. Yeterli zaman veya fiksatif penetrasyon İHK analizi üzerine bir &quot;gelgit işareti&quot; olarak görülebilir bağırsak kriptlerin içinde çözünürlük kaybına neden olabilir izin vermek için çok kalın bölümlere bağlı Eksik tespit. Bundan başka, nükleer β-katenin hemen yanlısı sürece çekirdeğin dışına dağılacaktır gibi tespit, çok uzun süre uzatmak etmediğini önemlidirulaşıldığı ve formalin fiksasyonu aşağıdaki gömülü balmumu. ISC Niche Paneth Hücrelerinin Rolü Burada sunulan veriler etkili bir ISC kaybını takiben yetişkin bağırsakta kript rejenerasyonu Paneth hücrelerinin önemini göstermektedir. Ancak orada Ah-CRE o vil-Cre-ER T2 hedefleri ISCs nüfusu yedek ihtimalini kalmıştır. Tian ve diğ. 26 zarif Lgr5 hi ISCs Lgr5 lo karşılık ISCs nüfusu ile ikame edildiğini göstermiştir. Şimdi bu ISCs nedeniyle rezerv nüfus salgı hücre öncüleri 6,7 olarak tespit edilerek için Ah-CRE sisteminde bağışladı olduğu muhtemel görünüyor. ISC duruma dönmek için gerektiğinde bu salgı hücre öncüleri destekleyen olgun Paneth hücrenin önemi cevaplanması gereken kalır. Paneth hücrelerinin I teşkil gibiSC niş 8 ve onların hemşirelik işlevleri kendi öncüleri uzatmak olasıdır kalır kalori alımı 27 ve inflamasyon 28 ISC yanıtlarını düzenlenmesinde rol oynamaktadır. Yeni Yaklaşımlar ve Teknoloji Etkili Model İnsan Kolorektal Kanser için ISC keşfi şimdi Clarke ve diğerleri tarafından gözden 9 barsak biyoloji ve hastalık, gen ve hücre rollerini araştırmak için yeni fare modelleri oluşturmak için kullanılan genlerin belirlenmesine yol açmıştır. Bu teknik için tek sınırlama, Cre proteinini ifade etmek için genlerin tanımlanmasıdır. Şu ISCs rutin Lgr5 gen ekspresyon modeline göre koşullu transgenik fareler kullanılarak incelenmiştir. Lgr5 promoterinden Cre ifade Fareler aPC, en yaygın olarak kolorektal kanserde mutasyona uğramış gen (CRC silmek için kullanılmıştır), Orijin 25 hücre olarak ISC gösteren. Seçerek silme bu hücrelerde diğer CRC genleri hastalığın ilerlemesi içgörü sağlanması ve yayılır örneğin. PTEN 29. ISC işlevi ayrıntılı fikir özellikle ablasyon Lgr5 insan difteri toksini reseptörü kullanılarak farelerde hücrelerin -expressing tarafından alındığını (DTR) geninin Lgr5 içine lokusu 26 çaldı. Diğer stratejiler mutant proteinlerin 30 devam eden geri dönüşümlü ifadesini sağlayan Tet-O sistemi kullanın. Farklı hücreler 31 ve yerlerde 32,33 yılında gen (ler) değiştirmek için bu araçları kullanarak kanser başlatmak nasıl anlamak, ilerleme ve 34 metastaz için kullanılır. Alternatif uyuyan güzellik transpozon sistemi kullanılarak mutajenez ÇHS yeni sürücüleri tespitidir. Farelerde, teknikleri ve genetik değişim stratejileri sürekli gelişimi daha sabırlı, ilgili modeller geliştirmeye devam ediyor. Yeni methods bağırsak epitel ve ISCs karakterizasyonu için geliştirilmiştir. Akış kullanılarak elde edilebilir epitel hücre tiplerinin oranı karakterizasyonu sitometri Lektin ve CD24 35 farklı ekspresyonu göre. Potansiyel büyük anlayış ISC biyolojide kaydedilen ilerleme ve hastalık rolleri ex vivo organoid kültür sistemi kullanılarak 36 yapılacaktır. Bu sistem, bu çoğaltma ve fizyolojik olarak daha uygun bir şekilde ayırt 3B, kültür normal ve habis ISCs sağlar. Bu kişiselleştirilmiş tıp 37 önünü, in vitro hasta örnekleri üzerinde ilaçların doğrudan test sağlayacak umulmaktadır.

Memeli bağırsak lümen yüzeyi projeksiyonları gibi kriptalarının ve parmak tekrar birimlerinden özellikleri, lümen içine çıkıntı villus olarak adlandırılan. 4 gün 1 - Bu yüzey, yaklaşık her 3 tam kendini yenileme uğrar epitel sürekli bir tabakadır. Bu dinamik Doku hızla kök hücreleri bisiklet nüfusu tarafından desteklenmektedir (ISCs, aynı zamanda kript baz kolon hücreleri olarak da bilinir) ilk olarak Lgr5 geni 2,3 kendi ifadesi ile tanımlandı. Bu hücreler Lieberkühn kript altındaki özel bir niş bulunmaktadır. Başlangıçta, ISCs hızla bisiklet vardı keşif kök hücre doğada sakin olduğunu hakim fikri ile uyumsuz oldu. O durgun etiket nüfus crypt tabanına göre 4 pozisyonunda hücreleri, istinat öne sürülmüştür Lgr5 + ISC tanımlanmasına Önceki, ISCs 1 idi. Son zamanlarda yapılan araştırmalar hşimdi öncelikle kader komşuları 4,5 düzenlenir her crypt ekipotent bisiklet ISCs bir havuz olduğunu göstererek bu gözlemleri barıştırdı. Halinde bunlar, bu normalde salgı soyu adadık ancak ISC nüfus 6 hasar görmüşse ISCs dönebilirsiniz durgun hücreleri tarafından değiştirilebilir kaybolur. ISC komşuları ISCs veya kızları hücreler olabilir ya. ISCs çarpma ve hangi hatlar bağırsak lümen 1 epitel tabaka oluşturan özelleşmiş hücre tiplerine ayırt naif kızı hücreleri üretirler. Goblet, enteroendokrin, enterositler, püskül ve M hücreleri çeşitli emici ve düzenleyici işlevleri sağlamak lümen yüzeyine yukarı göç, ancak, Paneth hücreleri ISCs ile iç içe bulunmamakta crypt dibinde kalır. Son yıllarda ortaya konmuştur, bu naif kız çocuğu bir kısmınınbir salgı soy için mukadder er hücreleri yaralanma 6,7 üzerine bir ISC geri döndürme yeteneğine Lgr5 lo hücrelerini koruyarak hareketsiz etiket vardır. Nedeniyle kript rejenerasyon önemi bir öncelik ISCs ve komşuları, özellikle Paneth hücreleri arasındaki etkileşimleri anlamaya yerleştirildi. Paneth hücrelerinin ISCs 8 destekleyen niş önemli bir rol oynamaktadır. Bakterisit ürünlerinin yanı sıra Paneth hücrelerinin ISC yenileme veya farklılaşmasını düzenleyen yolları aktive sinyal molekülleri üretirler. Önceki çalışmalar onların kızları Paneth hücreleri 8 tarafından sağlanan temel niş sinyalleri için rekabet edebilecek ne zaman Lgr5 + ISCs sadece var olduğunu gösterdi. Bu çalışmalar, normal Lgr5 + ISCs üzerinde değil, onlar zarar ve bir Lgr5 lo nüfus ikmal gerektiren bir durumda Paneth hücrelerinin rolü incelenmiştir. <pclass = &quot;jove_content&quot;&gt; Biz transgenik fare modelleri 9,10 kullanılarak hücrelerin ve / veya genlerin işlevsel rolünü incelemek bağırsak biyoloji ve model hastalığını anlamak için. Sıkça bu modeller şartlı gen (ler) 9,10 değiştirmek için CRE-lox teknolojisini kullanmaktadır. Cre rekombinaz bakteriyofaj P1 izole integraz ailesinin bir site özgü rekombinaz olduğunu (rekombinasyon Nedenleri). Cre tanımlanan 34 bp arasındaki alana özgü rekombinasyon katalize &#39; Lox P &#39;siteleri (geçit P1 odağı χ). Fareler genetik Cre rekombinazın ifadesi üzerine eksize ilgi alanları kuşatan LoxP siteleri içerecek şekilde tasarlanmıştır. Bir hücre ya da gelişimsel belirli bir promotere Cre geni ekspresyonunu bağlama işleminin tahrip edici bir mekansal biçimde 9,10 yapılabilmesi için, bu oluşum safhasındaki ölümcül mutasyonlar aşılmasında özellikle yararlıdır sağlar. Ayrıca, bir alıcı yolu Cre ifade bağlayanBu yapay aktive edilebilir, zamansal değişiklikler izin verir. Bu teknolojiyi kullanarak, biz bağırsak epitel CatnB genini 11 inaktive. β-katenin, CatnB gen ürünü, ISC homeostazı tabi doğal Wnt sinyal yolunun bir anahtar düzenleyicisidir. Bu stratejiyi kullanarak iki önceki çalışmalarda çelişkili sonuçlar 12,13 üretti. AEVR ve ark., 12 tarafından yapılan çalışmada, kök hücre ve bağırsak homeostazisinin kaybı gösterdi. İrlanda ve ark. Oysa 14 çalışma hücre canlılığında bir azalma, aşağıdaki kript-villus ekseni CatnB eksprese vahşi tip hücrelerden yeniden doldurulur olduğunu bildirdi. Bu çalışmalarda önemli fark bağırsak epitel Cre ifade etmek için kullanılan promotör oldu. AEVR ve diğ., Çalışma t tatbik edilmesiyle aktive edilebilir östrojen reseptörüne bağlanmış villin gen promotörü kullanılıramoxifen (vil-Cre-ER T2) 15,16. Buna karşılık Ireland ve arkadaşlarının., Ksenobiyotik β-naphthoflavone (Ah-CRE) yanıt olarak Cre sentezlenmesini tahrik etmek için, sıçan sitokrom P450A1 (CYP1A1) geni promoter dizisi kullanılmıştır. Bu farklı sistemlere dair özellikler bu farklı gözlemler için hesap, iki hipotez oluşturulur. CatnB daha verimli ve böylece alt repopulation seviyelerine ISCs sayısını azaltarak, Ah-CRE kıyasla vil-Cre-ER T2 sistemi kullanılarak ISC silinir ilk. Alternatif olarak farklılaşmış bir hücre popülasyonunda CatnB silme diferansiyel kaynaklanıyordu. Vil-Cre-ER T2 sistemi hedefleri Ah-CRE sistemi ise crypt ve villuslarının tüm epitel hücreleri yalnızca ISC niş ve crypt olmayan Paneth hücreleri hedefliyor. Bu sistemler Behav incelenmesi için ideal araçlar teminISCs ve ior ve Paneth hücreleri ile etkileşimi. İşte biz Paneth hücrelerinin yaralanma 17 bağırsak cevabı aracılık önemli bir rol oynadığını belirlemek için bu sistemlerin nasıl kullandığını dayalı birçok detaylı protokoller sunuyoruz.

<table><tbody><tr><td>Acetate buffer</td><td>*</td><td>*</td><td>To make 100 ml: 4.8 ml 0.2 M Acetic acid, 45.2 ml 0.2 M Sodium acetate &amp;amp; 50 ml distilled water</td></tr><tr><td>Acetic acid</td><td>Fisher Scientific</td><td>C/0400/PB17</td><td></td></tr><tr><td>Acetic anhydride</td><td>Sigma</td><td>A6404</td><td></td></tr><tr><td>Acetic anhydride solution</td><td>*</td><td>*</td><td>2 M Acetic anhydride in 0.1 M triethanolamine hydrochloride</td></tr><tr><td>Alcian Blue</td><td>Sigma</td><td>A5268</td><td></td></tr><tr><td>Alcian Blue pH 2.5</td><td>*</td><td>*</td><td>To make 500 ml: 15 ml acetic acid, 5 g Alcian Blue &amp;amp; 485 ml distilled water</td></tr><tr><td>anti-digoxigenin alkaline phosphatase conjugated antibody</td><td>Abcam</td><td>ab119345</td><td></td></tr><tr><td>B(beta)-Naphthoflavone</td><td>Sigma</td><td>N3633</td><td>BNF, inject without allowing the solution to cool too much as compound will drop out of solution. Solution can be re-used &amp;ndash; store at -20 &amp;deg;C between uses, do not reheat more than twice.</td></tr><tr><td>Bloxall</td><td>Vector Labs</td><td>SP-6000</td><td></td></tr><tr><td>BM purple</td><td>Roche</td><td>11442074001</td><td></td></tr><tr><td>BSA</td><td>Sigma</td><td>A4503</td><td>Bovine serum albumin</td></tr><tr><td>Chloroform</td><td>Fisher Scientific</td><td>C/4920/17</td><td></td></tr><tr><td>Citrate Buffer/Antigen Unmasking Solution</td><td>Vector Labs</td><td>H-3300</td><td></td></tr><tr><td>Corn oil</td><td>Sigma</td><td>C8627</td><td></td></tr><tr><td>Demucifiying solution</td><td>*</td><td>*</td><td>For 500 ml: 50 ml glycerol, 50 ml Tris 0.1M pH8.8, 100 ml EtOH, 300 ml saline (0.9% NaCl in water), DTT 1.7 g.&amp;nbsp; Demucifying solution can be made in advance and stored, but DTT sholud be added just before incubation (340 mg/100 ml).</td></tr><tr><td>DEPC treated water</td><td>Life Technologies</td><td>750023</td><td></td></tr><tr><td>DTT</td><td>Sigma</td><td>101509944</td><td></td></tr><tr><td>EDTA</td><td>Sigma</td><td>O3690</td><td>0.5M</td></tr><tr><td>Ethanol</td><td>Fisher Scientific</td><td>E/0650DF/17</td><td></td></tr><tr><td>Filter paper</td><td>Whatman</td><td>3000917</td><td></td></tr><tr><td>Formaldehyde</td><td>Sigma</td><td>F8775</td><td></td></tr><tr><td>Formalin&amp;nbsp;</td><td>Sigma</td><td>SLBL11382V</td><td>Neutral buffered formalin</td></tr><tr><td>Formamide</td><td>Sigma</td><td>F5786</td><td></td></tr><tr><td>Glutaraldehye</td><td>Sigma</td><td>G6257</td><td></td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;2&lt;/sub&gt;</td><td>Sigma</td><td>216763</td><td></td></tr><tr><td>Haematoxylin</td><td>Raymond A Lamb</td><td>12698616</td><td></td></tr><tr><td>HBSS</td><td>Gibco</td><td>14175-053</td><td>HBSS (-MgCl2+; -CaCl2)</td></tr><tr><td>Hybridisation buffer</td><td>*</td><td>*</td><td>&amp;nbsp;5&amp;times; SSC, 50% formamide, 5% SDS, 1 mg/ml heparin, 1 mg/ml calf liver tRNA</td></tr><tr><td>Hydroquinone</td><td>Sigma</td><td>H9003</td><td></td></tr><tr><td>ImmPACT DAB Peroxidase</td><td>Vector Labs</td><td>SK-4105</td><td></td></tr><tr><td>Immpress HRP Anti-Mouse IgG Kit</td><td>Vector Labs</td><td>MP-7402</td><td></td></tr><tr><td>Immpress HRP Anti-Rabbit IgG Kit</td><td>Vector Labs</td><td>MP-7401</td><td></td></tr><tr><td>Intestinal tissue powder</td><td>*</td><td>*</td><td>The small intestines of 5 adult mice were combined and homogenised in the minimum volume of ice cold PBS. 4 volumes of ice cold acetone were added to the homogenised intestine, which was mixed thoroughly and incubated on ice for 30 min. This was centrifuged and the pellet was washed using ice cold acetone. This was further centrifuged and the resulting pellet spread onto filter paper and allowed to dry. Once thoroughly dry the material was ground to a fine powder using a pestle and mortar.&amp;nbsp;</td></tr><tr><td>K-ferricyanide</td><td>Sigma</td><td>P-3667</td><td></td></tr><tr><td>K-ferrocyanide</td><td>Sigma</td><td>P3289</td><td></td></tr><tr><td>Levamisole</td><td>Sigma</td><td>L0380000</td><td></td></tr><tr><td>Methacarn</td><td>*</td><td>*</td><td>60% Methanol:30% Chloroform:10% Acetic acid</td></tr><tr><td>Methanol</td><td>Fisher Scientific</td><td>M/4000/17</td><td></td></tr><tr><td>MgCl2</td><td>Sigma</td><td>M8266</td><td></td></tr><tr><td>Normal goat serum</td><td>Vector Labs</td><td>S-1012</td><td>NGS</td></tr><tr><td>Normal rabbit serum</td><td>Dako</td><td>X0902</td><td>NRS</td></tr><tr><td>NTMT</td><td>*</td><td>*</td><td>100 mM NaCl, 100 mM Tris HCl, 50 mM MgCl&lt;sub&gt;2&lt;/sub&gt;, 0.1% Tween20, 2 mM Levamisole</td></tr><tr><td>PAP pen</td><td>Vector</td><td>H-400</td><td></td></tr><tr><td>Paraformaldehyde</td><td>Sigma</td><td>P6148</td><td></td></tr><tr><td>PBT</td><td>*</td><td>*</td><td>0.5 M NaCl, 10 mM TrisHCL pH7.5, 0.1% Tween 20</td></tr><tr><td>Penicillin/Streptomycin</td><td>Gibco</td><td>15140-122</td><td>100x solutiuon.</td></tr><tr><td>Phosphate buffered saline (10x)</td><td>Fisher Scientific</td><td>BP3994</td><td>Dilluted 1:10 with distilled water to make 1x</td></tr><tr><td>PLL slides</td><td>Sigma</td><td>P0425-72EA</td><td>Poly-L-lysine microscope slides</td></tr><tr><td>Proteinase K</td><td>Sigma</td><td>P2308</td><td></td></tr><tr><td>Proteinase k solution</td><td>*</td><td>*</td><td>Dilute Proteinase K at 200 &amp;micro;g/ml in 50 mM Tris, 5 mM EDTA.</td></tr><tr><td>Ralwax</td><td>BDH</td><td>36154 7N</td><td></td></tr><tr><td>Reducer Solution</td><td>*</td><td>*</td><td>To make 100 ml: 1 g Hydroquinone, 5 g sodium sulphite &amp;amp; 100 ml distilled water</td></tr><tr><td>RnaseA</td><td>Sigma</td><td>R6148</td><td></td></tr><tr><td>Saline</td><td>*</td><td>*</td><td>0.9% NaCl in distilled water</td></tr><tr><td>SDS</td><td>Sigma</td><td>I3771</td><td></td></tr><tr><td>Sheep serum</td><td>Sigma</td><td>S3772</td><td></td></tr><tr><td>Silver nitrate</td><td>Sigma</td><td>S/1240/46</td><td></td></tr><tr><td>Silver solution</td><td>*</td><td>*</td><td>To make 100 ml: 10 ml Acetate buffer, 87 ml distilled water, 3 ml 1% silver nitrate</td></tr><tr><td>Sodium acetate</td><td>Fisher Scientific</td><td>S/2120/53</td><td></td></tr><tr><td>Sodium Chloride</td><td>Sigma</td><td>S6753</td><td>NaCl</td></tr><tr><td>Sodium sulfite</td><td>Sigma</td><td>239321</td><td></td></tr><tr><td>SSC</td><td>Sigma</td><td>93017</td><td>20x saline sodium citrate</td></tr><tr><td>Surgical tape</td><td>Fisher Scientific</td><td>12960495</td><td></td></tr><tr><td>Tamoxifen</td><td>Sigma</td><td>T5648</td><td>TAM, inject without allowing the solution to cool too much as compound will drop out of solution. Solution can be re-used &amp;ndash; store at -20 &amp;deg;C between uses, do not reheat more than twice.</td></tr><tr><td>TBS/T</td><td>Cell Signalling</td><td>#9997</td><td></td></tr><tr><td>Triethanolamine hydrochloride</td><td>Sigma</td><td>T1502</td><td></td></tr><tr><td>Tris-HCL</td><td>Invitrogen</td><td>15567-027</td><td></td></tr><tr><td>Tween20</td><td>Sigma</td><td>TP9416</td><td></td></tr><tr><td>VectaMount</td><td>Vector Labs</td><td>H-5000</td><td></td></tr><tr><td>VectaShield Hardset mounting Medium with DAPI</td><td>Vector Labs</td><td>H-1500</td><td></td></tr><tr><td>Vectastain ABC Kit</td><td>Vector Labs</td><td>PK-4001</td><td></td></tr><tr><td>X-gal</td><td>Promega</td><td>V3941</td><td></td></tr><tr><td>X-gal fixative</td><td>*</td><td>*</td><td>2% formaldehyde, 0.1% glutaraldehyde in 1x PBS</td></tr><tr><td>X-gal stain</td><td>*</td><td>*</td><td>X-gal stain; 200 &amp;#956;l X-gal (A) in 50 ml solution B (0.214 g MgCl2, 0.48 g K-ferricyanide, 0.734 g K-ferrocyanide in 500 ml PBS).&amp;nbsp; Solution B can be made up oin advance and stored at 4 &amp;deg;C</td></tr><tr><td>Xylene</td><td>Fisher Scientific</td><td>X/0200/21</td><td></td></tr></tbody></table>

protocols for analyzing the role of paneth cells in regenerating the murine intestine using conditional cre-lox mouse models

7 gün - memeli bağırsak epitel yüzeyi her 3 yenileyen dinamik bir dokudur. Hızla Lgr5 geninin kendi ifadesi ile karakterize bağırsak kök hücreleri (ISCs) bisiklet nüfusu bu yenilenme sürecini belirlenen anlama. Bunlar yaralanma durumunda bunların yerine yeteneğine Bmi-1 ifadesi ile işaretlenmiş bir sakin kök hücre popülasyonu, tarafından desteklenmektedir. Bu nüfus arasındaki etkileşimi araştıran hastalığı ve kanser rollerini anlamak için çok önemlidir. ISCs bağırsak yüzeyindeki crypts içinde var, bu nişler epitel Yenileyici de ISC destekliyoruz. Bir önceki Lgr5 ISC&#39;nin &#39;stemness&#39; yakından komşu Paneth hücreleri varlığına bağlı olduğunu göstermiştir edildiği gibi, aktif ve pasif ISCs arasındaki etkileşim olasılığı, kovan içinde diğer farklılaşmış hücreleri içerir. Koşullu CRE-lox Fareyi kullanarakmodeller Paneth hücreleri varlığında veya yokluğunda aktif ISCs çoğunluğu silme etkisi test edilmiştir. Burada bağırsak karakterize ve taahhüt teknikler ve analiz Paneth hücrelerinin önemli hakaret aşağıdaki kurtarma yardım ISC niş içinde çok önemli bir rol oynadığını göstermektedir açıklar.

Watch this Scientific Journal Video about Protocols for Analyzing the Role of Paneth Cells in Regenerating the Murine Intestine using Conditional Cre-lox Mouse Models at JoVE.com

Protocols for Analyzing the Role of Paneth Cells in Regenerating the Murine Intestine using Conditional Cre-lox Mouse Models

Bağırsak epitel kök hücreler (ISCs) Paneth hücreleri ile iç içe. Bu hücreler ISCs destekleyen ve antibakteriyel koruma sağlamak ISC, soyunu ayırt edilirler. İşte biz Paneth hücrelerinin bağırsak epithelia sürdürmek çok önemli bir rol oynadığını kurmak için transgenik fare koşullu modellerini nasıl kullandıklarını göstermektedir.

Şartlı kullanarak Fare İnce Bağırsağında Yenileyici içinde Paneth Hücrelerinin Rolü analiz için protokoller<em&gt; Cre-lox</em&gt; Fare Modelleri

The epithelial surface of the mammalian intestine is a dynamic tissue that renews every 3 - 7 days. Understanding this renewal process identified a ...

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Nanyang Technological University

Research

JoVE Journal

Developmental Biology

Protocols for Analyzing the Role of Paneth Cells in Regenerating the Murine Intestine using Conditional Cre-lox Mouse Models

17.6K Görüntüleme.  Cardiff University.  Bağırsak epitel kök hücreler (ISCs) Paneth hücreleri ile iç içe. Bu hücreler ISCs destekleyen ve antibakteriyel koruma sağlamak ISC, soyunu ayırt edilirler. İşte biz Paneth hücrelerinin bağırsak epithelia sürdürmek çok önemli bir rol oynadığını kurmak için transgenik fare koşullu modellerini nasıl kullandıklarını göstermektedir. 

Video: Protocols for Analyzing the Role of Paneth Cells in Regenerating the Murine Intestine using Conditional Cre-lox Mouse Models

Using In Vivo and Tissue and Cell Explant Approaches to Study the Morphogenesis and Pathogenesis of the Embryonic and Perinatal Aorta

The aorta is the largest artery in the body. The aortic wall is composed of an inner layer of endothelial cells, a middle layer of alternating elastic lamellae and smooth muscle cells (SMCs), and an outer layer of fibroblasts and extracellular matrix. In contrast to the widespread study of pathological models (e.g., atherosclerosis) in the adult aorta, much less is known about the embryonic and perinatal aorta. Here, we focus on SMCs and provide protocols for the analysis of the morphogenesis and pathogenesis of embryonic and perinatal aortic SMCs in normal development and disease. Specifically, the four protocols included are: i) in vivo embryonic fate mapping and clonal analysis; ii) explant embryonic aorta culture; iii) SMC isolation from the perinatal aorta; and iv) subcutaneous osmotic mini-pump placement in pregnant (or non-pregnant) mice. Thus, these approaches facilitate the investigation of the origin(s), fate, and clonal architecture of SMCs in the aorta in vivo. They allow for modulating embryonic aorta morphogenesis in utero by continuous exposure to pharmacological agents. In addition, isolated aortic tissue explants or aortic SMCs can be used to gain insights into the role of specific gene targets during fundamental processes such as muscularization, proliferation, and migration. These hypothesis-generating experiments on isolated SMCs and the explanted aorta can then be assessed in the in vivo context through pharmacological and genetic approaches.

Using In Vivo and Tissue and Cell Explant Approaches to Study the Morphogenesis and Pathogenesis of the Embryonic and Perinatal Aorta

Protocols for studying the embryonic and perinatal murine aorta using in vivo clonal analysis and fate mapping, aortic explants, and isolated smooth muscle cells are detailed here. These diverse approaches facilitate the investigation of the morphogenesis of the embryonic and perinatal aorta in normal development and the pathogenesis in disease.

Morfogenez ve embriyonik ve Perinatal aort patogenezi okumaya vivo içinde ve doku ve hücre Explant yaklaşımları kullanma

The aorta is the largest artery in the body. The aortic wall is composed of an inner layer of endothelial cells, a middle layer of alternating elastic ...

Gelişim Biyolojisi

Three-Dimensional Culture of Murine Colonic Crypts to Study Intestinal Stem Cell Function Ex Vivo

The intestinal epithelium regenerates every 5-7 days, and is controlled by the intestinal epithelial stem cell (IESC) population located at the bottom of the crypt region. IESCs include active stem cells, which self-renew and differentiate into various epithelial cell types, and quiescent stem cells, which serve as the reserve stem cells in the case of injury. Regeneration of the intestinal epithelium is controlled by the self-renewing and differentiating capabilities of these active IESCs. In addition, the balance of the crypt stem cell population and maintenance of the stem cell niche are essential for intestinal regeneration. Organoid culture is an important and attractive approach to studying proteins, signaling molecules, and environmental cues that regulate stem cell survival and functions. This model is less expensive, less time-consuming, and more manipulatable than animal models. Organoids also mimic the tissue microenvironment, providing in vivo relevance. The present protocol describes the isolation of colonic crypts, embedding these isolated crypt cells into a three-dimensional gel matrix system and culturing crypt cells to form colonic organoids capable of self-organization, proliferation, self-renewal, and differentiation. This model allows one to manipulate the environment-knocking out specific proteins such as claudin-7, activating/deactivating signaling pathways, etc.-to study how these effects influence the functioning of colonic stem cells. Specifically, the role of tight junction protein claudin-7 in colonic stem cell function was examined. Claudin-7 is vital for maintaining intestinal homeostasis and barrier function and integrity. Knockout of claudin-7 in mice induces an inflammatory bowel disease-like phenotype exhibiting intestinal inflammation, epithelial hyperplasia, weight loss, mucosal ulcerations, epithelial cell sloughing, and adenomas. Previously, it was reported that claudin-7 is required for intestinal epithelial stem cell functions in the small intestine. In this protocol, a colonic organoid culture system is established to study the role of claudin-7 in the large intestine.

Three-Dimensional Culture of Murine Colonic Crypts to Study Intestinal Stem Cell Function Ex Vivo

The present protocol describes establishing a murine colonic organoid system to study the activity and functioning of colonic stem cells in a claudin-7 knockout model.

Bağırsak Kök Hücre Fonksiyonunu Incelemek için Murin Kolonik Kriptlerinin Üç Boyutlu Kültürü Ex Vivo

The intestinal epithelium regenerates every 5-7 days, and is controlled by the intestinal epithelial stem cell (IESC) population located at the bottom of ...

Kanser Araştırmaları

The Organoid Reconstitution Assay (ORA) for the Functional Analysis of Intestinal Stem and Niche Cells

The intestinal epithelium is characterized by an extremely rapid turnover rate. In mammals, the entire epithelial lining is renewed within 4 - 5 days. Adult intestinal stem cells reside at the bottom of the crypts of Lieberk&#252;hn, are earmarked by expression of the Lgr5 gene, and preserve homeostasis through their characteristic high proliferative rate1. Throughout the small intestine, Lgr5+ stem cells are intermingled with specialized secretory cells called Paneth cells. Paneth cells secrete antibacterial compounds (i.e., lysozyme and cryptdins/defensins) and exert a controlling role on the intestinal flora. More recently, a novel function has been discovered for Paneth cells, namely their capacity to provide niche support to Lgr5+ stem cells through several key ligands as Wnt3, EGF, and Dll12.
When isolated ex vivo and cultured in the presence of specific growth factors and extracellular matrix components, whole intestinal crypts give rise to long-lived and self-renewing 3D structures called organoids that highly resemble the crypt-villus epithelial architecture of the adult small intestine3. Organoid cultures, when established from whole crypts, allow the study of self-renewal and differentiation of the intestinal stem cell niche, though without addressing the contribution of its individual components, namely the Lgr5+ and Paneth cells.
Here, we describe a novel approach to the organoid assay that takes advantage of the ability of Paneth and Lgr5+ cells to associate and form organoids when co-cultured. This approach, here referred to as &#34;organoid reconstitution assay&#34; (ORA), allows the genetic and biochemical modification of Paneth or Lgr5+ stem cells, followed by reconstitution into organoids. As such, it allows the functional analysis of the two main components of the intestinal stem cell niche.

The Organoid Reconstitution Assay ORA for the Functional Analysis of Intestinal Stem and Niche Cells

Intestinal organoid cultures are established from whole crypts and do not allow the analysis of self-renewal and differentiation in a cell-specific fashion. This protocol describes reconstitution of sorted stem (Lgr5+) and niche (Paneth) cells, which give rise to organoids while enabling their prior biochemical and genetic modification and functional analysis.

Fonksiyonel analiz bağırsak kök ve niş hücre Organoid sulandırma tahlil (ORA)

The intestinal epithelium is characterized by an extremely rapid turnover rate. In mammals, the entire epithelial lining is renewed within 4 - 5 days. ...

Biyomühendislik

Functional Assessment of Intestinal Permeability and Neutrophil Transepithelial Migration in Mice using a Standardized Intestinal Loop Model

The intestinal mucosa is lined by a single layer of epithelial cells that forms a dynamic barrier allowing paracellular transport of nutrients and water while preventing passage of luminal bacteria and exogenous substances. A breach of this layer results in increased permeability to luminal contents and recruitment of immune cells, both of which are hallmarks of pathologic states in the gut including inflammatory bowel disease (IBD). 
Mechanisms regulating epithelial barrier function and transepithelial migration (TEpM) of polymorphonuclear neutrophils (PMN) are incompletely understood due to the lack of experimental in vivo methods allowing quantitative analyses. Here, we describe a robust murine experimental model that employs an exteriorized intestinal segment of either ileum or proximal colon. The exteriorized intestinal loop (iLoop) is fully vascularized and offers physiological advantages over ex vivo chamber-based approaches commonly used to study permeability and PMN migration across epithelial cell monolayers.
We demonstrate two applications of this model in detail: (1) quantitative measurement of intestinal permeability through detection of fluorescence-labeled dextrans in serum after intraluminal injection, (2) quantitative assessment of migrated PMN across the intestinal epithelium into the gut lumen after intraluminal introduction of chemoattractants. We demonstrate feasibility of this model and provide results utilizing the iLoop in mice lacking the epithelial tight junction-associated protein JAM-A compared to controls. JAM-A has been shown to regulate epithelial barrier function as well as PMN TEpM during inflammatory responses. Our results using the iLoop confirm previous studies and highlight the importance of JAM-A in regulation of intestinal permeability and PMN TEpM in vivo during homeostasis and disease. 
The iLoop model provides a highly standardized method for reproducible in vivo studies of intestinal homeostasis and inflammation and will significantly enhance understanding of intestinal barrier function and mucosal inflammation in diseases such as IBD.

Dysregulated intestinal epithelial barrier function and immune responses are hallmarks of inflammatory bowel disease that remain poorly investigated due to a lack of physiological models. Here, we describe a mouse intestinal loop model that employs a well-vascularized and exteriorized bowel segment to study mucosal permeability and leukocyte recruitment in vivo.

Standartlaştırılmış Bağırsak Döngüsü Modeli Kullanılarak Farelerde Bağırsak Geçirgenliği ve Nötrofil Transepithelial Göçün Fonksiyonel Değerlendirmesi

The intestinal mucosa is lined by a single layer of epithelial cells that forms a dynamic barrier allowing paracellular transport of nutrients and water ...

İmmünoloji ve Enfeksiyon

Co-Culture of Murine Small Intestine Epithelial Organoids with Innate Lymphoid Cells

Complex co-cultures of organoids with immune cells provide a versatile tool for interrogating the bi-directional interactions that underpin the delicate balance of mucosal homeostasis. These 3D, multi-cellular systems offer a reductionist model for addressing multi-factorial diseases and resolving technical difficulties that arise when studying rare cell types such as tissue-resident innate lymphoid cells (ILCs). This article describes a murine system that combines small intestine organoids and small intestine lamina propria derived helper-like type-1 ILCs (ILC1s), which can be readily extended to other ILC or immune populations. ILCs are a tissue-resident population that is particularly enriched in the mucosa, where they promote homeostasis and rapidly respond to damage or infection. Organoid co-cultures with ILCs have already begun shedding light on new epithelial-immune signaling modules in the gut, revealing how different ILC subsets impact intestinal epithelial barrier integrity and regeneration. This protocol will enable further investigations into reciprocal interactions between epithelial and immune cells, which hold the potential to provide new insights into the mechanisms of mucosal homeostasis and inflammation.

This protocol offers detailed instructions for establishing murine small intestine organoids, isolating type-1 innate lymphoid cells from the murine small intestine lamina propria, and establishing 3-dimensional (3D) co-cultures between both cell types to study bi-directional interactions between intestinal epithelial cells and type-1 innate lymphoid cells.

Murin İnce Bağırsak Epitel Organoidlerinin Doğuştan Lenfoid Hücrelerle Ko-Kültürü

Complex co-cultures of organoids with immune cells provide a versatile tool for interrogating the bi-directional interactions that underpin the delicate ...

Improved Swiss-rolling Technique for Intestinal Tissue Preparation for Immunohistochemical and Immunofluorescent Analyses

Understanding the role of factors that regulate intestinal epithelial homeostasis and response to injury and regeneration is important. The current literature describes several different methodological approaches to obtain images of intestinal tissues for data validation. In this paper, we delineate a common protocol relating to the derivation and processing of mouse intestinal tissues. Proper fixation of intestinal tissues and Swiss-roll techniques that enhance intestinal epithelial morphology are discussed. Postresection processing and reorientation of embedded intestinal tissues are critical in obtaining paraffin-embedded blocks that display intact intestinal structural features after sectioning. The Swiss-rolling technique helps in histological assessment of the complete intestinal or colonic sections examined. An ability to differentiate intestinal structural features can be vital in quantitative measurements of intestinal inflammation and tumorigenesis along the entire length. Finally, paraffin-embedded sections are ideal for robust processing using both immunohistochemical and immunofluorescent detection methods. Nonfluorescent immunohistochemical sections provide a vibrant image of the tissue detailing different cellular structural features but do not provide flexibility for intracellular co-localization experiments. Multiple fluorescent channels can be appropriately utilized with immunofluorescent detection for co-localization experiments, lending support to mechanistic studies.

Accurate identification and location of epithelial cells along the intestinal mucosal lining are essential to define different cell lineages. Proper imaging of intestinal tissues is crucial for identification of protein expression patterns with maximum resolution. This study aims to delineate the optimal methods and conditions for processing mouse intestinal tissues.

Immünohistokimyasal ve immünofloresan Analizleri için Bağırsak Doku Hazırlama için geliştirilmiş Swiss-haddeleme Tekniği

Understanding the role of factors that regulate intestinal epithelial homeostasis and response to injury and regeneration is important. The current ...

Biyoloji

Generation of Murine Primary Colon Epithelial Monolayers from Intestinal Crypts

The intestinal epithelium is comprised of a single layer of cells that act as a barrier between the gut lumen and the interior of the body. Disruption in the continuity of this barrier can result in inflammatory disorders such as inflammatory bowel disease. One of the limitations in the study of intestinal epithelial biology has been the lack of primary cell culture models, which has obliged researchers to use model cell lines derived from carcinomas. The advent of three dimensional (3D) enteroids has given epithelial biologists a powerful tool to generate primary cell cultures, nevertheless, these structures are embedded in extracellular matrix and lack the maturity characteristic of differentiated intestinal epithelial cells. Several techniques to generate intestinal epithelial monolayers have been published, but most are derived from established 3D enteroids making the process laborious and expensive. Here we describe a protocol to generate primary epithelial colon monolayers directly from murine intestinal crypts. We also detail experimental approaches that can be used with this model such as the generation of confluent cultures on permeable filters, confluent monolayer for scratch wound healing studies and sparse and confluent monolayers for immunofluorescence analysis.

In this protocol, we describe how to generate murine primary epithelial colon monolayers directly from intestinal crypts. We provide experimental approaches to generate confluent monolayers on permeable filters, confluent monolayers for scratch wound healing and biochemical studies, and sparse and confluent monolayers for immunofluorescence analysis.

Bağırsak Mezarlarından Murine Primer Kolon Epitel Monolayerlerinin Üretimi

The intestinal epithelium is comprised of a single layer of cells that act as a barrier between the gut lumen and the interior of the body. Disruption in ...

Intestinal Epithelial Regeneration in Response to Ionizing Irradiation

The intestinal epithelium consists of a single layer of cells yet contains multiple types of terminally differentiated cells, which are generated by the active proliferation of intestinal stem cells located at the bottom of intestinal crypts. However, during events of acute intestinal injury, these active intestinal stem cells undergo cell death. Gamma irradiation is a widely used colorectal cancer treatment, which, while therapeutically efficacious, has the side effect of depleting the active stem cell pool. Indeed, patients frequently experience gastrointestinal radiation syndrome while undergoing radiotherapy, in part due to active stem cell depletion. The loss of active intestinal stem cells in intestinal crypts activates a pool of typically quiescent reserve intestinal stem cells and induces dedifferentiation of secretory and enterocyte precursor cells. If not for these cells, the intestinal epithelium would lack the ability to recover from radiotherapy and other such major tissue insults. New advances in lineage-tracing technologies allow tracking of the activation, differentiation, and migration of cells during regeneration and have been successfully employed for studying this in the gut. This study aims to depict a method for the analysis of cells within the mouse intestinal epithelium following radiation injury.

The gastrointestinal tract is one of the most sensitive organs to injury upon radiotherapeutic cancer treatments. It is simultaneously an organ system with one of the highest regenerative capacities following such insults. The presented protocol describes an efficient method to study the regenerative capacity of the intestinal epithelium.

İyonlaştırıcı Işınlamaya Yanıt Olarak Bağırsak Epitelyal Rejenerasyonu

The intestinal epithelium consists of a single layer of cells yet contains multiple types of terminally differentiated cells, which are generated by the ...

Bağırsak İltihabının Yerleşik Murin Kolonoidleri Üzerindeki Epitelyal Etkileri

Studying the Epithelial Effects of Intestinal Inflammation In Vitro on Established Murine Colonoids

The intestinal epithelium plays an essential role in human health, providing a barrier between the host and the external environment. This highly dynamic cell layer provides the first line of defense between microbial and immune populations and helps to modulate the intestinal immune response. Disruption of the epithelial barrier is a hallmark of inflammatory bowel disease (IBD) and is of interest for therapeutic targeting. The 3-dimensional colonoid culture system is an extremely useful in vitro model for studying intestinal stem cell dynamics and epithelial cell physiology in IBD pathogenesis. Ideally, establishing colonoids from the inflamed epithelial tissue of animals would be most beneficial in assessing the genetic and molecular influences on disease. However, we have shown that in vivo epithelial changes are not necessarily retained in colonoids established from mice with acute inflammation. To address this limitation, we have developed a protocol to treat colonoids with a cocktail of inflammatory mediators that are typically elevated during IBD. While this system can be applied ubiquitously to various culture conditions, this protocol emphasizes treatment on both differentiated colonoids and 2-dimensional monolayers derived from established colonoids. In a traditional culture setting, colonoids are enriched with intestinal stem cells, providing an ideal environment to study the stem cell niche. However, this system does not allow for an analysis of the features of intestinal physiology, such as barrier function. Further, traditional colonoids do not offer the opportunity to study the cellular response of terminally differentiated epithelial cells to proinflammatory stimuli. The methods presented here provide an alternative experimental framework to address these limitations. The 2-dimensional monolayer culture system also offers an opportunity for therapeutic drug screening ex vivo. This polarized layer of cells can be treated with inflammatory mediators on the basal side of the cell and concomitantly with putative therapeutics apically to determine their utility in IBD treatment.

Yazar Spotlight: Bağırsak İltihabının Yerleşik Murin Kolonoidleri Üzerindeki İn Vitro Epitelyal Etkilerinin İncelenmesi  

We describe a protocol detailing the isolation of murine colonic crypts for the development of 3-dimensional colonoids. The established colonoids can then be terminally differentiated to reflect the cellular composition of the host epithelium prior to receiving an inflammatory challenge or being directed to establish an epithelial monolayer.

İntestinal İnflamasyonun Yerleşik Murin Kolonoidleri Üzerindeki İn Vitro Epitelyal Etkilerinin İncelenmesi

The intestinal epithelium plays an essential role in human health, providing a barrier between the host and the external environment. This highly dynamic ...

Şartlı kullanarak Fare İnce Bağırsağında Yenileyici içinde Paneth Hücrelerinin Rolü analiz için protokoller

Özet

Daha Fazla Video Keşfet

Morfogenez ve embriyonik ve Perinatal aort patogenezi okumaya vivo içinde ve doku ve hücre Explant yaklaşımları kullanma

Bağırsak Kök Hücre Fonksiyonunu Incelemek için Murin Kolonik Kriptlerinin Üç Boyutlu Kültürü Ex Vivo

Fonksiyonel analiz bağırsak kök ve niş hücre Organoid sulandırma tahlil (ORA)

Standartlaştırılmış Bağırsak Döngüsü Modeli Kullanılarak Farelerde Bağırsak Geçirgenliği ve Nötrofil Transepithelial Göçün Fonksiyonel Değerlendirmesi

Murin İnce Bağırsak Epitel Organoidlerinin Doğuştan Lenfoid Hücrelerle Ko-Kültürü

Immünohistokimyasal ve immünofloresan Analizleri için Bağırsak Doku Hazırlama için geliştirilmiş Swiss-haddeleme Tekniği

Bağırsak Mezarlarından Murine Primer Kolon Epitel Monolayerlerinin Üretimi

İyonlaştırıcı Işınlamaya Yanıt Olarak Bağırsak Epitelyal Rejenerasyonu

İntestinal İnflamasyonun Yerleşik Murin Kolonoidleri Üzerindeki İn Vitro Epitelyal Etkilerinin İncelenmesi

İntestinal İnflamasyonun Yerleşik Murin Kolonoidleri Üzerindeki İn Vitro Epitelyal Etkilerinin İncelenmesi