이 프로젝트는 플로리다 주에서 스크립스 및 보너스 번호는 각각 종합 의료 과학 국립 연구소와 아동 건강 및 인간 발달의 국립 연구소에서 R01GM085079 및 R21HD061304에 돈도에 의해 부분적으로 지원되었다. 이것은 스크립스 연구소의 논문 번호는 20917입니다.

이 프로토콜은 두 가지 주요 단계로 분리 수 있습니다 : 필요한 경우 (1) 마우스 testis 세포의 분리와 Hoechst 33342 얼룩이에 의해 배아 세포부터, 감수 분열의 모든 단계를 포함하여 관련 meiotic 분수의 정렬 (2) 외과를 따라 라운드 spermatids. 일단 수집이 매우 풍부한 meiotic 인구는 분석의 광범위한 사용하실 수 있습니다. 이 프로토콜은 하나의 성인 testis의 분리를 설명, 볼륨 아동 또는 추가 testes에 대해 적절하게 적용할 수 있습니다. 1. Testis 분리 <ol><li> 15 - ML 튜브에 놓으 decapsulated testis합니다. </li><li> Collagenase 유형 I. 120 U / ML을 포함 Gey의 밸런스 소금 솔루션 3 - ML (GBSS)를 추가 </li><li> DNAse I (50 % 글리세롤의 1mg/ml 주식 솔루션) 10 μl를 추가하고 교제를 끊다 시작 고환 tubules가 나타날 때까지 손으로 적극적으로 그것을 흔들어. </li><li> 33 ° C.에 15 분 120 RPM의 최대 가로 선동 </li><li> 실온에서 수직으로 1 분 가만히 따르다 및 뜨는 폐기. </li><li> 1.5 단계 1.2를 반복합니다. </li><li> Collagenase 유형 I, 1mM HCL 솔루션, 그리고 DNAse I (1mg/ml) 10 μl에 resuspended 50mg/ml 트립신 주식 솔루션 50 μl를 포함 GBSS 2.5 ML를 추가하고 튜브를 여러 번 반전. </li><li> 33 ° C.에 15 분 120 RPM의 최대 가로 선동 </li><li> 넓은 구멍과 플라스틱 일회용 파스퇴르 pipet을 사용하여, 피펫 부드럽게 위아래로 3 min.No의 대단히 짧은 시간을 위해이 시점에서 볼 수 있습니다. </li><li> 트립신 30 μl, DNAse I, DMSO (10 MG / ML)에 resuspended Hoechst 33342 40 μl, 10 μl를 추가하고 튜브를 여러 번 반전. </li><li> 33 ° C.에 15 분 120 RPM의 최대 가로 선동 </li><li> 소태아 혈청 (FCS)의 400 μl를 추가하고 트립신을 inactivate로 반전하여 섞는다. </li><li> 최종 얼룩은 Hoechst 33342 50 μl DMSO (10 MG / ML)에 resuspended, 그리고 DNAse I (1 MG / ML) 10 μl를 추가하여 수행됩니다. </li><li> 33 ° C.에 15 분 120 RPM의 최대 가로 선동 </li><li> dissociated testis 샘플 후 두 40 μm의 GBSS 통과하는 50 ML 원뿔 관을 통해 사전에 침수 일회용 필터, 일회용 파스퇴르와 함께 여러 번 pipetting하여 솔루션에 추가되고 예제가 부드럽게 혼합합니다 propidium의 요오드화물의 다음 5 μl (PI) 피펫. </li><li> 샘플은 18 게이지 바늘을 통해 5 ML 플라스틱 주사기로 전송됩니다. 후자는 샘플 제공을위한 22 게이지 바늘로 대체됩니다. 주사기는 얼음에 저장하고 빛으로부터 외과 처리를위한 준비까지 보호됩니다. </li></ol> 2. 외과의 설치 및 정제 <ol><li> 정렬은 백톤 디킨슨 - 아리아 IIu 세포 분류기에서 수행되었다. 다른 장비를 사용하여 특히 설명한 조건에 따라서 시작점으로 사용해야합니다. 우리는 이전에 조건을 사용 7,8 설명했다. </li><li> 아리아 IIu은 UV 레이저를하지 않기 때문에, 우리는 앞으로 측면 산란 감지 488nm 청색 레이저를 사용 이외에 405nm 바이올렛 레이저를 사용하여 Hoescht 얼룩을 검출을위한 프로토콜을 적응. 또한, 일부 필터는 개선 흩어져 플롯 선명도에서 발생하는 몇 가지 빨간색 레이저 leakiness을 제한하기 위해 수정되었습니다. </li><li> 바이올렛 레이저 Hoescht 블루 방출의 검출을위한 450/40nm 밴드 패스와 Hoescht 레드 방출을위한 585/42nm 밴드 패스로 구성되었다. 502nm 긴 패스는 적색 형광에서 파란색으로 구분하는 데 사용되었다. </li><li> 100 μm의 노즐은 28000 방울 / 초의 드롭 드라이브 주파수로 사용되었다. 샘플 임계값 속도는 약 4000 이벤트 / 초되었다. 온도 제어 옵션은 4 샘플 및 수집 튜브를 유지하는 데 사용된 ° C 정렬의 전체 기간. 또한, 샘플 교반 기능은 일종의 전역 sedimenting에서 샘플을 방지하기 위해 200 rpm으로 사용되었다. </li><li> 보통 2-3 testes은 각 인구 0.5 - 2.0x10 6 전지 (대표 섹션을 참조)의 컬렉션을 허용 6시간 정렬마다 처리되었습니다. </li><li> 샘플은 주사기에서 적절 약 750μl의 aliquots으로 정렬되었습니다. 한편, 이러한 일시 중지하는 동안 컬렉션 튜브는 4 유지되었습니다 ° C, 빛으로부터 보호하고, 부드럽게 사전 재개 정렬 혼합. </li><li> 정렬 샘플 10% FCS와 보충 250μl를 포함한 DMEM 12x75mm 유리 borosilicated 수집 튜브에 수집되었다. </li></ol> 3. 대표 결과 : 일반 외과 프로필은 그림 1에 표시됩니다. 감수 분열의 주요 단계를 모두 식별하고 전설에 표시됩니다. Hoechst 33342는 최적되지 얼룩 경우, 글로벌 프로파일은 훨씬 더 컴팩트 나타나고 이하 정의합니다. 일반적인 문제는 급속한 세포 clumping을 유도합니다 충분한 DNAse를 추가하지하시오. 모든 기소 단계에서 추가 DNAse의 추가는 일반적으로이 문제를 해결합니다. 프리즈 일DNAse 주식 (-20 ° C에 저장된)의 awing는 효소 활동의 급속한 손실이 결과로, 최소로 보관해야합니다. Spo11는 meiotic 재조합 핫스팟 12 사이트에서 더블 스트랜드 나누기를 안내 meiotic endonuclease이다. 그림 2는 전형적인 불임 감수 분열 12 결과 더블 스트랜드 브레이크가 형성되지 않은 Spo11 - NULL testis의 프로필,뿐만 아니라를 보여줍니다 감수 분열의이 첫 번째 물결의 비동기 자연을 밝히지 13 일 옛 마우스, 사전 puberous 프로필입니다. synaptonemal 복잡한 단백질 3 (SCP3) 및 phosphorylated 히스톤 H2AX 항체의 조합을 사용하여 표준 cytogenetic 분석은 무대 특정 세포의 감수 분열의 마커가 처음으로 elswhere 11 설명한 정렬 meiotic 세포의 순수 자연을 확인하는 데 사용해야합니다. <img src="/files/ftp_upload/2602/2602fig1.jpg" alt="그림 1" /> 그림 1. 와일드 타입의 감수 분열의 외과 프로필. A) 대표 스캐터 플롯이 표시됩니다. 문이 세포가 표시됩니다. 대부분 비어있는 점막 및 spermatid 꼬리를 포함한 성인 testis에있는 파편의 많은 양의 있습니다. B) 대표 PI의 줄거리는 샘플에있는 PI 긍정적인 세포의 매우 제한된 금액을 보여줍니다. 전형적인 게이트가 표시됩니다. C) 대표 야생 타입 Hoechst 33342 외과 프로필이 표시됩니다. 진학이 방법을 사용하여 정화 수있는 다양한 meiotic 세포 집단이 표시됩니다 : spermatogonia (SP), 사전 leptotene (PL), leptotene - 접합기에 이어지는시기로 (L / Z), 초기 Pachytene (EP), 중간 Pachytene ( MP), 늦은 Pachytene (LP), diplotene (D), 그리고 원형 spermatids (RS). <img src="/files/ftp_upload/2602/2602fig2.jpg" alt="그림 2" /> 그림 2. Spo11 - NULL과 야생 형 13 일 meiotic 외과 프로필. A) 일반적인 Spo11 - NULL 프로필 접합기에 이어지는시기로 / leptotene 초기 pachytene 과거의 어떤 단계가 감지 수 없습니다 명확한 meiotic 실패와 표시됩니다. B) 13 일 된 야생 형 남성 마우스의 프로필 leptotene / 접합기에 이어지는시기로 세포의 높은 농도를 나타냅니다. 감수 분열의 첫 번째 물결은 명확하게이 방법을 사용하여 시각, 오히려 비동기입니다.

<ol>
	<li>Meistrich, M. L., Bruce, W. R., Clermont, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+composition+of+fractions+of+mouse+testis+cells+following+velocity+sedimentation+separation.">Cellular composition of fractions of mouse testis cells following velocity sedimentation separation.</a> Exp. Cell Res. 79, 213-227 (1973).</li><li>Grabske, R. J., Lake, S., Gledhill, B. L., Meistrich, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Centrifugal+elutriation:+separation+of+spermatogenic+cells+on+the+basis+of+sedimentation+velocity.">Centrifugal elutriation: separation of spermatogenic cells on the basis of sedimentation velocity.</a> J. Cell. Physiol. 86, 177-189 (1975).</li><li>Purification, A. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=culture,+and+fractionation+of+spermatogenic+cells.">culture, and fractionation of spermatogenic cells.</a> Methods Enzymol. 225, 84-113 (1993).</li><li>Romrell, L. J., Bellve, A. R., Fawcett, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Separation+of+mouse+spermatogenic+cells+by+sedimentation+velocity.+A+morphological+characterization.">Separation of mouse spermatogenic cells by sedimentation velocity. A morphological characterization.</a> Dev. Biol. 49, 119-131 (1976).</li><li>Meistrich, M. L., Trostle, P. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Separation+of+mouse+testis+cells+by+equilibrium+density+centrifugation+in+renografin+gradients.">Separation of mouse testis cells by equilibrium density centrifugation in renografin gradients.</a> Exp. Cell Res. 92, 231-244 (1975).</li><li>Namekawa, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Postmeiotic+sex+chromatin+in+the+male+germline+of+mice.">Postmeiotic sex chromatin in the male germline of mice.</a> Curr. Biol. 16, 660-667 (2006).</li><li>Lassalle, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Side+Population'+cells+in+adult+mouse+testis+express+Bcrp1+gene+and+are+enriched+in+spermatogonia+and+germinal+stem+cells.">Side Population' cells in adult mouse testis express Bcrp1 gene and are enriched in spermatogonia and germinal stem cells.</a> Development. 131, 479-487 (2004).</li><li>Bastos, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometric+characterization+of+viable+meiotic+and+postmeiotic+cells+by+Hoechst+33342+in+mouse+spermatogenesis.">Flow cytometric characterization of viable meiotic and postmeiotic cells by Hoechst 33342 in mouse spermatogenesis.</a> Cytometry A. 65, 40-49 (2005).</li><li>Chowdhury, R., Bois, P. R., Feingold, E., Sherman, S. L., Cheung, V. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+analysis+of+variation+in+human+meiotic+recombination.">Genetic analysis of variation in human meiotic recombination.</a> PLoS Genet. 5, e1000648-e1000648 (2009).</li><li>Roig, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+TRIP13/PCH2+is+required+for+recombination+and+normal+higher-order+chromosome+structure+during+meiosis.">Mouse TRIP13/PCH2 is required for recombination and normal higher-order chromosome structure during meiosis.</a> PLoS Genet. 6, (2010).</li><li>Getun, I. V., Wu, Z. K., Khalil, A. M., Bois, P. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nucleosome+occupancy+landscape+and+dynamics+at+mouse+recombination+hotspots.">Nucleosome occupancy landscape and dynamics at mouse recombination hotspots.</a> EMBO Rep. 11, 555-560 (2010).</li><li>Romanienko, P. J., Camerini-Otero, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mouse+Spo11+gene+is+required+for+meiotic+chromosome+synapsis.">The mouse Spo11 gene is required for meiotic chromosome synapsis.</a> Mol. Cell. 6, 975-987 (2000).</li></ol>

관심 없음 충돌 선언하지 않습니다.

여기에 제시 프로토콜 사람이 동시에 조사이 근본적인 프로세스의 역학을 연구 수 있도록, 성인 남자 생쥐에서 매우 높은 순도로 meiotic 무대 세포의 전체 범위를 정화 수 있습니다. 정화 세포는 RNA 추출 9,10, nucleosome 매핑 11, 재조합 분자 탐지, 단백질 분석, 그리고 많은 이르기까지 다양한 애플 리케이션에 사용할 수 있습니다. 그러나, 검출 방법은 정화 meiotic 세포의 금액에 적응?...

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
		
		<div>
		<table border="1">
		<thead>
		<tr>
		<th>Material Name</th>
		<th>Type</th>
		<th>Company</th>
		<th>Catalogue Number</th>
		<th>Comment</th>
		</tr>
		</thead>
		<tbody>
		
<tr>
<td>Collagenase Type-1</td>
<td>&nbsp;</td>
<td>Worthington</td>
<td>CLSS1</td>
<td>Dissolve to 12,000U/ml in GBSS, store at 4&deg;C</td>
</tr>
<tr>
<td>Trypsin</td>
<td>&nbsp;</td>
<td>Worthington</td>
<td>TRL3</td>
<td>Dissolve in 1mM HCl to 50mg/ml, store at 4&deg;C</td>
</tr>
<tr>
<td>Hoechst 33342</td>
<td>&nbsp;</td>
<td>Arcos</td>
<td>230001000</td>
<td>Saturated solution (10mg/ml in DMSO, store at 4&deg;C</td>
</tr>
<tr>
<td>DNAse I</td>
<td>&nbsp;</td>
<td>Sigma-Aldrich</td>
<td>DNEP</td>
<td>Dissolve in water/50% glycerol to 1mg/ml, store at -20&deg;C</td>
</tr>
<tr>
<td>Gey&#x2019;s Balance Salt Solution </td>
<td>&nbsp;</td>
<td>Sigma-Aldrich</td>
<td>G9779</td>
<td>&nbsp;</td>
<tr>
<td>6" Transfer Pipet</td>
<td>&nbsp;</td>
<td>Fisher Scientific</td>
<td>137119D</td>
<td>&nbsp;</td>		</tbody>
		</table>
		</div>

flow cytometry purification of mouse meiotic cells

testis의 세포 유형의 이질적인 성격과 meiotic 세포 배양 모델의 부재는 감수 분열 동안 매니 페스트의 독특한 차별화 프로그램의 연구에 상당한 장애물을하고 있습니다. elutriation 또는 Staput (침전) BSA 및 / 또는 percoll 그라디언트를 사용하는 두 가지 주요 방법은, 다양한 도로, 성인 및 미숙 동물 모두에서 다양한 meiotic 분수를 정화하기 위해 개발되었습니다. 이러한 방법 중 두 세포 크기와 세포 meiotic에게 1-5 분리 밀도에 의존하고 있습니다. 전반적으로, 몇 가지 세포 인구 6 제외하고, 이러한 프로토콜 자세한 분자 분석을 위해 필요한 수많은 meiotic 세포 집단의 충분한 순도를 얻을하지. 또한, 같은 방법으로 meiotic 세포의 보통 한 종류는 meiotic 세포 샘플을 비교했을 때 재현성과 균질성에 관한 복잡한 여분 수준을 추가 주어진 시간에서 정화 수 있습니다. 여기, 우리는 Hoechst 33342 얼룩 7,8와 함께 외과를 사용하여 배아 세포에서 라운드 spermatids로, 하나는 쉽게 시각화 식별하고, meiotic 세포를 정화 수있는 세련된 방법을 설명합니다. 이 방법은 전체 meiotic 프로세스의 전반적인 스냅샷을 제공하며 하나는 높은 감수 분열 대부분의 단계에서 가능한 세포를 정화 수 있습니다. 이러한 정화 전지는 다음 meiotic 재조합 11 핫스팟에서 예제 유전자 발현 9,10의 변화와 nucleosome 인의 역학에 대해, 세포의 감수 분열을 통해 진행을 수반하는 분자 변경 사항을 자세하게 분석할 수 있습니다.

Watch this Scientific Journal Video about Flow Cytometry Purification of Mouse Meiotic Cells at JoVE.com

Flow Cytometry Purification of Mouse Meiotic Cells

마우스 testis에서 높은 정화 가능한 meiotic 분수를 얻는 효과적인 방법은 형광 활성 세포 분류 (외과)와 세련된 세포 분리 프로토콜을 결합하는, 설명되어 있습니다. 이 방법은 DNA의 내용과 개별 meiotic 분수의 핵 밀도의 차이 활용합니다.

마우스 Meiotic 셀 유동세포계측법의 정제

The heterogeneous nature of cell types in the testis and the absence of meiotic cell culture models have been significant hurdles to the study of the ...

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Meiosis

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17.6K 조회수.  The Scripps Research Institute. 마우스 testis에서 높은 정화 가능한 meiotic 분수를 얻는 효과적인 방법은 형광 활성 세포 분류 (외과)와 세련된 세포 분리 프로토콜을 결합하는, 설명되어 있습니다. 이 방법은 DNA의 내용과 개별 meiotic 분수의 핵 밀도의 차이 활용합니다.

비디오: Flow Cytometry Purification of Mouse Meiotic Cells

Staining of Proteins in Gels with Coomassie G-250 without Organic Solvent and Acetic Acid

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents (Methanol, Ethanol or 2-Propanol) and acetic acid are used for fixation, staining and destaining of proteins in a gel after SDS-PAGE. To speed up the procedure, heating the staining solution in the microwave oven for a short time is frequently used. This usually results in evaporation of toxic or hazardous Methanol, Ethanol or 2-Propanol and a strong smell of acetic acid in the lab which should be avoided due to safety considerations. In a protocol originally published in two patent applications by E.M. Wondrak (US2001046709 (A1), US6319720 (B1)), an alternative composition of the staining solution is described in which no organic solvent or acid is used. The CBB is dissolved in bidistilled water (60-80mg of CBB G-250 per liter) and 35 mM HCl is added as the only other compound in the staining solution. The CBB staning of the gel is done after SDS-PAGE and thorough washing of the gel in bidistilled water. By heating the gel during the washing and staining steps, the process can be finished faster and no toxic or hazardous compunds are evaporating. The staining of proteins occurs already within 1 minute after heating the gel in staining solution and is fully developed after 15-30 min with a slightly blue background that is destained completely by prolonged washing of the stained gel in bidistilled water, without affecting the stained protein bands.

A short protocol for protein staining with Coomassie Brilliant Blue (CBB) G-250 in polyacrylamide gels is described without using organic solvents or acetic acid as in the classical staining procedures with CBB.

유기 용매 및 초산없이 쿠매시 G - 250로 젤의 단백질 염색법

In classical protein staining protocols using Coomassie Brilliant Blue (CBB), solutions with high contents of toxic and flammable organic solvents ...

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생물학

Flow Cytometry-based Purification of S. cerevisiae Zygotes

Zygotes are essential intermediates between haploid and diploid states in the life cycle of many organisms, including yeast (Figure 1) 1. S. cerevisiae zygotes result from the fusion of haploid cells of distinct mating type (MATa, MATalpha) and give rise to corresponding stable diploids that successively generate as many as 20 diploid progeny as a result of their strikingly asymmetric mitotic divisions 2. Zygote formation is orchestrated by a complex sequence of events: In this process, soluble mating factors bind to cognate receptors, triggering receptor-mediated signaling cascades that facilitate interruption of the cell cycle and culminate in cell-cell fusion. Zygotes may be considered a model for progenitor or stem cell function.
Although much has been learned about the formation of zygotes and although zygotes have been used to investigate cell-molecular questions of general significance, almost all studies have made use of mating mixtures in which zygotes are intermixed with a majority population of haploid cells 3-8. Many aspects of the biochemistry of zygote formation and the continuing life of the zygote therefore remain uninvestigated.
Reports of purification of yeast zygotes describe protocols based on their sedimentation properties 9; however, this sedimentation-based procedure did not yield nearly 90% purity in our hands. Moreover, it has the disadvantage that cells are exposed to hypertonic sorbitol. We therefore have developed a versatile purification procedure. For this purpose, pairs of haploid cells expressing red or green fluorescent proteins were co-incubated to allow zygote formation, harvested at various times, and the resulting zygotes were purified using a flow cytometry-based sorting protocol. This technique provides a convenient visual assessment of purity and maturation. The average purity of the fraction is approximately 90%. According to the timing of harvest, zygotes of varying degrees of maturity can be recovered. The purified samples provide a convenient point of departure for "-omic" studies, for recovery of initial progeny, and for systematic investigation of this progenitor cell.

Flow Cytometry-based Purification of S. cerevisiae Zygotes

To purify zygotes of S. cerevisiae, haploid cells of opposite mating type were engineered to express red or green fluorescent proteins, co-incubated to allow zygote formation, and fractionated using a flow cytometry-based protocol. The highly-enriched fraction enables subsequent "-omic" studies, recovery of initial progeny, and systematic investigation of zygote morphogenesis.

의 흐름 세포 계측법 기반 정화<em&gt; S. cerevisiae</em&gt; Zygotes

Zygotes are essential intermediates between haploid and diploid states in the life cycle of many organisms, including yeast (Figure 1) 1. S. cerevisiae ...

Optimized Staining and Proliferation Modeling Methods for Cell Division Monitoring using Cell Tracking Dyes

Fluorescent cell tracking dyes, in combination with flow and image cytometry, are powerful tools with which to study the interactions and fates of different cell types in vitro and in vivo.1-5 Although there are literally thousands of publications using such dyes, some of the most commonly encountered cell tracking applications include monitoring of:
<ol>
	<li>stem and progenitor cell quiescence, proliferation and/or differentiation6-8</li>
	<li>antigen-driven membrane transfer9 and/or precursor cell proliferation3,4,10-18 and</li>
	<li>immune regulatory and effector cell function1,18-21.</li>
</ol>
Commercially available cell tracking dyes vary widely in their chemistries and fluorescence properties but the great majority fall into one of two classes based on their mechanism of cell labeling. "Membrane dyes", typified by PKH26, are highly lipophilic dyes that partition stably but non-covalently into cell membranes1,2,11. "Protein dyes", typified by CFSE, are amino-reactive dyes that form stable covalent bonds with cell proteins4,16,18. Each class has its own advantages and limitations. The key to their successful use, particularly in multicolor studies where multiple dyes are used to track different cell types, is therefore to understand the critical issues enabling optimal use of each class2-4,16,18,24.
The protocols included here highlight three common causes of poor or variable results when using cell-tracking dyes. These are:
<ol>
	<li>Failure to achieve bright, uniform, reproducible labeling. This is a necessary starting point for any cell tracking study but requires attention to different variables when using membrane dyes than when using protein dyes or equilibrium binding reagents such as antibodies.</li>
	<li>Suboptimal fluorochrome combinations and/or failure to include critical compensation controls. Tracking dye fluorescence is typically 102 - 103 times brighter than antibody fluorescence. It is therefore essential to verify that the presence of tracking dye does not compromise the ability to detect other probes being used.</li>
	<li>Failure to obtain a good fit with peak modeling software. Such software allows quantitative comparison of proliferative responses across different populations or stimuli based on precursor frequency or other metrics. Obtaining a good fit, however, requires exclusion of dead/dying cells that can distort dye dilution profiles and matching of the assumptions underlying the model with characteristics of the observed dye dilution profile.</li>
</ol>
Examples given here illustrate how these variables can affect results when using membrane and/or protein dyes to monitor cell proliferation.

Successful use of cell tracking dyes to monitor immune cell function and proliferation involves several critical steps. We describe methods for: 1) obtaining bright, uniform, reproducible label-ing with membrane dyes; 2) selecting fluorochromes and data acquisition conditions; and 3) choosing a model to quantify cell proliferation based on dye dilution.

셀 추적 염료를 사용하여 전지 부문 모니터링에 최적화 된 착색 및 확산 모델링 방법

Fluorescent cell tracking dyes, in combination with flow and image cytometry, are powerful tools with which to study the interactions and fates of ...

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

A variety of cellular processes, both physiological and pathophysiological, require or are governed by calcium, including exocytosis, mitochondrial function, cell death, cell metabolism and cell migration to name but a few. Cytosolic calcium is normally maintained at low nanomolar concentrations; rather it is found in high micromolar to millimolar concentrations in the endoplasmic reticulum, mitochondrial matrix and the extracellular compartment. Upon stimulation, a transient increase in cytosolic calcium serves to signal downstream events. Detecting changes in cytosolic calcium is normally performed using a live cell imaging set up with calcium binding dyes that exhibit either an increase in fluorescence intensity or a shift in the emission wavelength upon calcium binding. However, a live cell imaging set up is not freely accessible to all researchers. Alternative detection methods have been optimized for immunological cells with flow cytometry and for non-immunological adherent cells with a fluorescence microplate reader. Here, we describe an optimized, simple method for detecting changes in epithelial cells with flow cytometry using a single wavelength calcium binding dye. Adherent renal proximal tubule epithelial cells, which are normally difficult to load with dyes, were loaded with a fluorescent cell permeable calcium binding dye in the presence of probenecid, brought into suspension and calcium signals were monitored before and after addition of thapsigargin, tunicamycin and ionomycin.

Calcium is involved in numerous physiological and pathophysiological signaling pathways. Live cell imaging requires specialized equipment and can be time consuming. A quick, simple method using a flow cytometer to determine relative changes in cytosolic calcium in adherent epithelial cells brought into suspension was optimized.

유동 세포 계측법에 의한 신장 상피 세포에서 세포 내 칼슘 측정

A variety of cellular processes, both physiological and pathophysiological, require or are governed by calcium, including exocytosis, mitochondrial ...

Meiotic Spindle Assessment in Mouse Oocytes by siRNA-mediated Silencing

Errors in chromosome segregation during meiotic division in gametes can lead to aneuploidy that is subsequently transmitted to the embryo upon fertilization. The resulting aneuploidy in developing embryos is recognized as a major cause of pregnancy loss and congenital birth defects such as Down&#8217;s syndrome. Accurate chromosome segregation is critically dependent on the formation of the microtubule spindle apparatus, yet this process remains poorly understood in mammalian oocytes. Intriguingly, meiotic spindle assembly differs from mitosis and is regulated, at least in part, by unique microtubule organizing centers (MTOCs). Assessment of MTOC-associated proteins can provide valuable insight into the regulatory mechanisms that govern meiotic spindle formation and organization. Here, we describe methods to isolate mouse oocytes and deplete MTOC-associated proteins using a siRNA-mediated approach to test function. In addition, we describe oocyte fixation and immunofluorescence analysis conditions to evaluate meiotic spindle formation and organization.

Here, we present a protocol for specific siRNA-mediated mRNA depletion followed by immunofluorescence analysis to evaluate meiotic spindle assembly and organization in mouse oocytes. This protocol is suitable for in vitro depletion of transcripts and functional assessment of different spindle and/or MTOC-associated factors in oocytes.

siRNA를 매개 음소거로 마우스 난 모세포의 감수 스핀들 평가

Errors in chromosome segregation during meiotic division in gametes can lead to aneuploidy that is subsequently transmitted to the embryo upon ...

LED Thermo Flow &#8212; Combining Optogenetics with Flow Cytometry

Optogenetic tools allow isolated, functional investigations of almost any signaling molecule within complex signaling pathways. A major obstacle is the controlled delivery of light to the cell sample and hence the most popular tools for optogenetic studies are microscopy-based cell analyses and in vitro experiments. The flow cytometer has major advantages over a microscope, including the ability to rapidly measure thousands of cells at single cell resolution. However, it is not yet widely used in optogenetics. Here, we present a device that combines the power of optogenetics and flow cytometry: the LED Thermo Flow. This device illuminates cells at specific wavelengths, light intensities and temperatures during flow cytometric measurements. It can be built at low cost and be used with most common flow cytometers. To demonstrate its utility, we characterized the photoswitching kinetics of Dronpa proteins in vivo and in real time. This protocol can be adapted to almost all optically controlled substances and substantially expands the set of possible experiments. More importantly, it will greatly simplify the discovery and development of new optogenetic tools.

Optically controlled substances are powerful tools to study signaling pathways. To expand the spectrum of possible experiments, we developed a device for studying optically controlled substances in real time using flow cytometry: the LED Thermo Flow.

LED 열 흐름 - 유동 세포 계측법으로 Optogenetics 결합

Optogenetic tools allow isolated, functional investigations of almost any signaling molecule within complex signaling pathways. A major obstacle is the ...

Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes

Mammalian meiosis is a dynamic developmental process that occurs in germ cells and can be studied and characterized. Using a method to spread nuclei on the surface of slides (rather than dropping them from a height), we demonstrate an optimized technique on mouse spermatocytes that was first described in 1997. This method is widely used in laboratories to study mammalian meiosis because it yields a plethora of high quality nuclei undergoing substages of prophase I. Seminiferous tubules are first placed in a hypotonic solution to swell spermatocytes. Then spermatocytes are released into a sucrose solution to create a cell suspension, and nuclei are spread onto fixative-soaked glass slides. Following immunostaining, a diversity of proteins germane to meiotic processes can be examined. For example, proteins of the synaptonemal complex, a tripartite structure that connects the chromosome axes/cores of homologs together can be easily visualized. Meiotic recombination proteins, which are involved in repair of DNA double-strand breaks by homologous recombination, can also be immunostained to evaluate progression of prophase I. Here we describe and demonstrate in detail a technique widely used to study mammalian meiosis in spermatocytes from juvenile or adult male mice.

Meiosis is the developmental process by which gametes are formed through a single round of DNA replication and two successive rounds of chromosome segregation. Mammalian meiosis can be examined by utilizing a technique to prepare meiotic chromosome spreads. Here, we demonstrate a method of preparing surface-spread nuclei from mouse spermatocytes.

Meiotic 염색체의 준비에서 마우스 Spermatocytes 확산

Mammalian meiosis is a dynamic developmental process that occurs in germ cells and can be studied and characterized. Using a method to spread nuclei on ...

Analysis of Cell Suspensions Isolated from Solid Tissues by Spectral Flow Cytometry

Flow cytometry has been used for the past 40 years to define and analyze the phenotype of lymphoid and other hematopoietic cells. Initially restricted to the analysis of a few fluorochromes, currently there are dozens of different fluorescent dyes, and up to 14-18 different dyes can be combined at a time. However, several limitations still impair the analytical capabilities. Because of the multiplicity of fluorescent probes, data analysis has become increasingly complex due to the need of large, multi-parametric compensation matrices. Moreover, mutant mouse models carrying fluorescent proteins to detect and trace specific cell types in different tissues have become available, so the analysis (by flow cytometry) of auto-fluorescent cell suspensions obtained from solid organs is required. Spectral flow cytometry, which distinguishes the shapes of emission spectra along a wide range of continuous wavelengths, addresses some of these problems. The data is analyzed with an algorithm that replaces compensation matrices and treats auto-fluorescence as an independent parameter. Thus, spectral flow cytometry should be capable of discriminating fluorochromes with similar emission peaks and can provide a multi-parametric analysis without compensation requirements.
This protocol describes the spectral flow cytometry analysis, allowing for a 21-parameter (19 fluorescent probes) characterization and the management of an auto-fluorescent signal, providing high resolution in minor population detection. The results presented here show that spectral flow cytometry presents advantages in the analysis of cell populations from tissues difficult to characterize in conventional flow cytometry, such as the heart and the intestine. Spectral flow cytometry thus demonstrates the multi-parametric analytical capacity of high-performing conventional flow cytometry without the requirement for compensation and enables auto-fluorescence management.

This article describes spectral cytometry, a new approach in flow cytometry that uses the shapes of emission spectra to distinguish fluorochromes. An algorithm replaces compensations and can treat auto-fluorescence as an independent parameter. This new approach allows for the proper analysis of cells isolated from solid organs.

스펙트럼 유동 세포 계측법에 의해 고체 조직에서 분리 한 세포 현탁액의 분석

Flow cytometry has been used for the past 40 years to define and analyze the phenotype of lymphoid and other hematopoietic cells. Initially restricted to ...

Trans-inner Cell Mass Injection of Embryonic Stem Cells Leads to Higher Chimerism Rates

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current blastocyst injection protocol. Here we report that a simple rotation of the embryo, and injection through Trans-Inner cell mass (TICM) increased the percentage of chimeric mice from 31% to 50%, with no additional equipment or further specialized training. 26 different inbred clones, and 35 total clones were injected over a period of 9 months. There was no significant difference in either pregnancy rate or recovery rate of embryos between traditional injection techniques and TICM. Therefore, without any major alteration in the injection process and a simple positioning of the blastocyst and injecting through the ICM, releasing the ES cells into the blastocoel cavity can potentially improve the quantity of chimeric production and subsequent germline transmission.

Here we present a protocol to increase chimera production without the use of new equipment. A simple orientation change of the embryo for injection can increase the number of embryos produced, and potentially reduce the timeline to germline transmission.

트랜스-내부 세포 배아 줄기 세포의 대량 주입 리드 더 높은 Chimerism 요금

In an effort to increase efficiency in the creation of genetically modified mice via ES Cell methodologies, we present an adaptation to the current ...

Measurement of Mitochondrial Mass and Membrane Potential in Hematopoietic Stem Cells and T-cells by Flow Cytometry

A fine balance of quiescence, self-renewal, and differentiation is key to preserve the hematopoietic stem cell (HSC) pool and maintain lifelong production of all mature blood cells. In recent years cellular metabolism has emerged as a crucial regulator of HSC function and fate. We have previously demonstrated that modulation of mitochondrial metabolism influences HSC fate. Specifically, by chemically uncoupling the electron transport chain we were able to maintain HSC function in culture conditions that normally induce rapid differentiation. However, limiting HSC numbers often precludes the use of standard assays to measure HSC metabolism and therefore predict their function. Here, we report a simple flow cytometry assay that allows reliable measurement of mitochondrial membrane potential and mitochondrial mass in scarce cells such as HSCs. We discuss the isolation of HSCs from mouse bone marrow and measurement of mitochondrial mass and membrane potential post ex vivo culture. As an example, we show the modulation of these parameters in HSCs via treatment with a metabolic modulator. Moreover, we extend the application of this methodology on human peripheral blood-derived T cells and human tumor infiltrating lymphocytes (TILs), showing dramatic differences in their mitochondrial profiles, possibly reflecting different T cell functionality. We believe this assay can be employed in screenings to identify modulators of mitochondrial metabolism in various cell types in different contexts.

Here we describe a reliable method to measure mitochondrial mass and membrane potential in ex vivo cultured hematopoietic stem cells and T cells.

유세포측정에 의한 조혈줄기세포 및 T세포의 미토콘드리아 질량 및 막 전위 측정

A fine balance of quiescence, self-renewal, and differentiation is key to preserve the hematopoietic stem cell (HSC) pool and maintain lifelong production ...