著者は、落射蛍光顕微鏡に関する技術的助言のための博士レオニードボルコフとEricブシャールに感謝したいです。 財政的援助 GBに（＃1 MOP-93781を付与）カナダ衛生研究所によって資金を供給

動物のケアは、シャーブルック大学の動物の管理と使用委員会に従いました。 1.チューブの準備<ol><li>細胞選別の前日には、5ミリリットルポリプロピレン丸底チューブに熱不活性化ウシ胎児血清（FBS）1〜2mlのを追加し、15ミリリットル、50 mlのポリプロピレン製コニカルチューブに。 重要なステップ：プロトコルで使用されるすべてのチューブが被覆されていることを確認してください。 注意：FBSコーティングは、管壁に付着する生殖細胞を防ぐことができます。 </li><li>ゆっくりとチューブが均一に回転子を使用して被覆するために4℃での反転により、O / Nを混ぜます。 </li><li>翌日、デカントすることにより、コーティングされたチューブからFBSを削除します。 <ol><li> *重要なステップ：5ミリリットルポリプロピレン丸底チューブおよび細胞調製のために使用される15、50 mlチューブは、（プロトコルは2.11から2.1ステップ）完全にファニング（サイドストリームのすなわち、不正確な偏差）を防止するために、FBSを空にしていることを確認します。 FBSを削除するには、P200のピペットを使用してください。 <br/&gt;注：残留FBSチューブでソートする前には、細胞または細胞選別の際に使用される他の管の汚染の損失につながる可能性</li><li>精製された細胞を収集するために使用される下部チューブラウンド5ミリリットルポリプロピレンでFBSの小残留量（約100〜200μl）を残して下さい。 </li></ol></li></ol> 2.細胞調製<ol><li> CO 2窒息続く（5％誘導はその後、2％に維持）、O 2 /イソフルランを使用して麻酔下で1人の男性にマウスを生け贄に捧げます。 </li><li>消費税​​及び1.5ミリリットルチューブにバッファをソートする500μlの小さなハサミでカプセル開放を行う両方の精巣およびミンチ。 </li><li>フラッシュ生殖最初切り捨て100-1,000μlの先端で1.5ミリリットルチューブで優しく上下にピペッティングにより精細管からの細胞、およびその後そのまま100-1,000μlの先端で。 </li><li> 40μmのセルストレーナーを使用して、1つの濾過工程によって破片や塊を取り除き、50mlのコニカルチューブの前にろ液を集めますiouslyステップ1でFBSをコーティングしました。 </li><li>以前手順1でコーティングされた15ミリリットルコニカルチューブに合計3 mlの容量と転送ろ液までのバッファを並べ替えて、フィルタを1回洗浄します。 </li><li> 0.8 mMのEDTAの最終濃度を得るために、細胞懸濁液（3ミリリットル48μl）を1ミリリットル当たり50ミリモルのEDTA pHが8の16μLを追加します。 </li><li>生殖細胞を固定するために、ゆっくりと乳白色の懸濁液が生成される穏やかな撹拌（低速でボルテックス）で10mlのピペットを使用して、氷冷100％エタノール3容量を追加します。 重要なステップ：ゆっくりとエタノールを加え細胞調製物の完全性を維持することが重要と重要です。私たちは、エタノールの急速な添加は効率をソートの主な減少で得られた細胞溶解を引き起こすことを指摘しました。 3ミリリットルの細胞懸濁液は、エタノール9mlを約1分で添加されるべきです。 </li><li>反転による時々混合しながら氷上で15分間細胞をインキュベートします。 </li><li> 5分間800×gで遠心し細胞懸濁液とクリアを削除上清。 </li><li>静かにバッファをソート2ml中の固定された生殖細胞を再​​懸濁します。 </li><li> SYTO16 DNA色素（DMSO中の1 mM溶液）の4μlを添加して、（光から保護）は、少なくとも30分間インキュベートします。 注：これは容易に精子細胞の高度に圧縮された核内に組み込まれる透過性DNA色素であるため、最高のソート結果をSYTO16を用いて得られます。 </li></ol> 3.セルソーターを設定注：ここでは、4-レーザー（405nmの - 紫、488nmの - 青、561 nmの - 黄緑色、633nmの - 赤）20パラメータBDFACSAria IIIセルソーターを用いています。 BD FACSDiva 6.1.3ソフトウェアは、データを視覚化し、分析するために使用されます。設定が使用ソータの種類に応じて変えることができます。 <ol><li>選別前に流体のシャットダウン手順（ソフトウェアで「サイトメーター」メニュー）の間にシース液として70％エタノールを実行して、FACSソーターを滅菌します。ソフトウェアのツールバーにある「サイトメーター」を選択し、「流体のshを選択。 &quot;をutdownプロセスで述べた手順に従ってください。 </li><li>準備し、任意の結晶および汚染物質を除去するように、0.22μmのフィルターを用いて1×PBSをフィルタリングします。タンク内の上側の溶接線にシースタンクを埋めます。 </li><li>ソフトウェアを起動し、ログインします。選別前に少なくとも30分間レーザーを温めるために、FACSソーターを開始します。流体工学からエタノールを洗い流すために、2つの流体起動プロセスを実行します。ソフトウェアのツールバーにある「サイトメーター」を選択し、「流体の起動」を選択します。プロセスで述べた手順に従ってください。 注意：これは、通常のシース液（1×PBS）で流体工学を復元します。 </li><li>ブロックソート、蒸留水で偏向板をきれいにし、それらを徹底的に乾燥させます。超音波処理浴中で2分間蒸留水管に入れ100μmのノズルを超音波処理します。徹底的にノズルを拭きます。 </li><li>フローセルに100μmのノズルを挿入し、12にノズルロックレバーを時計回りに回します時間位置。 20 PSIにシース圧を設定します。 </li><li>ストリームをオンにして、周波数の目標値を取得するために振幅を調整（30前後）、ドロップ1（150前後）とギャップ（12前後）、安定した液滴切り離しパターン（数サテライト滴）を確立します。減衰をオフにします。 </li><li>ストリームがストレートで、ソートブロックの角度を変更することにより、廃棄物の吸引器の中心に当たることを確認します。注：10 psiで130μmのノズルも試験したと明らかな差は見られませんでした。 </li><li>黄緑色レーザ用、青紫、赤のため-77.39、37.33および-39.85 0に設定レーザー遅延。 </li><li>黄緑色レーザ用、青紫赤1.0、0.75と0.96のための1.14へのスケーリング設定の領域。 </li><li> （ソフトウェアの「サイドストリーム」ウィンドウ内の）試験ソートを使用して、サイ​​ドストリームがファニングされていないことを確認してください。彼らはmiddlを打つように、「サイドストリーム」ウィンドウでは、各副流の電圧スライダーを調整テストコレクションチューブのE。中央ストリームが固まっていない場合は、中央の流れを制限するために、2位、3位、および4 番目のドロップ設定を調整します。 </li><li>サイトメーターのセットアップとソフトウェアの追跡（CS＆T）アプリケーション（「サイトメーター」メニュー）を起動します。 </li><li>製造元の指示を使用して、サイ​​トメーターの性能の特徴付けおよび追跡を自動化するために、350μlのあたり1滴でサイトメーターセットアップおよび追跡ビーズを使用してください。 </li><li> CS＆Tのアプリケーションを終了します。 CS＆Tの設定を適用し、ストリーム・パラメータがまだ安定した液滴切離しパターンを可能にし、（「切り離しウィンドウ」で）を、製造業者の説明書に記載されているようにスイートスポットボタンをオンにしてください。 </li><li>蛍光ビーズを使用してドロップ遅延値を最適化（材料の表を参照のこと）。 <ol><li>ホルダーに収集チューブを取り付けます。ソートブロックのドアを開きます。 「サイドストリーム」ウィンドウで、「選択した電圧をオンにしますテストソート」と引き出しを開き、コレクションチューブにアクセスできるようにアスピレーター引き出しボタンをクリックします。 </li><li>彼らは、チューブの中央に入るように、サイドストリームを最適化します。必要に応じて値スライダを調整します。 </li><li>ソートブロックのドアを閉じて、中央に明るいビーズスポットを得るために、マイクロメーターダイヤルを調整してください。選択を解除廃棄引き出し、テストの並べ替えと電圧。コレクションチューブを外します。 </li><li>製造者の指示に従って降下遅延を最適化します。 <ol><li>簡単に説明すると、ビーズバイアルを激しく振とうし、PBS 0.5mlのビーズの1滴を希釈します。 </li><li>製造者の指示を使用して、ソフトウェアで使用可能なドロップディレイ実験テンプレートを使用して、ドロップ遅延を設定します。また、ドロップ遅延を設定するには、[自動ドロップ遅延機能を使用しています。 </li><li>蛍光ビーズのチューブをロードし、しきい値率が〜3,000〜4,000のイベント/秒になるまで流量を調整します。 「初期」と最後にソート精度を設定します。LY「ソートレイアウト」ウィンドウの「微調整」します。光学フィルタを選択して、ビーズを並べ替えます。 〜100％を左にソートされるまで、ドロップディレイを調整します。 注：この手順は必ず側流への関心の種の細胞ことを確認することが重要です。ビーズと光学フィルタ100％滴偏差に近い達成するために使用されます。 </li></ol></li></ol></li><li> FSC検出器ブロックの左端にFSC 1.5 ND（減光）フィルターを置きます。 （「サイトメーター」ウィンドウで、「レーザー」タブで）1.00に2.00マイクロ秒とFSCエリアのスケーリングにウィンドウの拡張機能を設定します。 </li><li>サンプルチューブをロードする前に、凝集を避けるために、サンプルラインの最後に50μmのサンプルフィルタラインを配置します。これを行うには、「サイトメーター」メニューの「サンプルフィルタを変更」を選択します。 </li><li>サイドストリーム間ファニングずに良好な分離を達成するために、試料流体の組成をテストしpolypropyleに付着する細胞を防ぐためにNEチューブ。 <ol><li>サンプルチューブをロードし、偏向板をオンにして引き出しを閉じた状態で「テストの並べ替え」を選択します。分離はあまりファニングせずに発生した場合、サイドストリームを見てください。 注：ファニング起因サンプル緩衝液中に高タンパク質濃度に思われます。 </li></ol></li><li> FACS装置にサンプルチューブをロードします。 300 rpmでのサンプルの攪拌と4℃の試料温度を選択します。 「取得ダッシュボード」の「データを取得」を選択します。 </li><li>必要に応じて、（3.0の最大流量で）5,000イベント/秒の最大値に適切なイベント・レートを達成するために、サンプルを希釈します。選別された細胞の純度を維持するように厳密にこれらの制限を尊重しています。 </li><li>分析し、細胞を選別するために、関心の集団に干渉することなく、破片を除去するためにFSC閾値を最適化します。対数目盛では、作るために530/30フィルタを備えた光電子増倍管（PMT）検出器の電圧を調整総人口の蛍光シグナルが陽性集団（ 図1、ゲート1）のスケールに収まると、ゲートことを確認してください。 </li><li> SYTO16陽性集団の前方散乱面積（FSC-A）/側方散乱エリア（SSC-A）のプロットを生成し、約110 VリニアスケールでにFSC-Aを調整し、SSC-A約150 Vに非常に大規模な細胞および細胞凝集体を排除しながら、対数スケールですべてのイベントを可視化しました。 </li><li> 「ソートレイアウト」ウィンドウで、「ソート精度モード」に設定」4ウェイ純度」に（収量マスク：0、純度マスク：32、位相マスク：0）。連続ソートのための「ターゲットイベント」メニューから「連続」を選択します。 </li><li> （「ソートレイアウト」ウィンドウ）のチューブに対応するフィールドでソートする集団を追加します。高い真ん中の周波数と端部で低い周波数を持つものと集団を置きます。 、並べ替え中に2,500 Vに電圧プレートを設定し、サンプル収集トンを保ちます氷上ubes。 </li></ol> 4.セルソーティング<ol><li>すぐにソートする前に、丸底チューブを先にコーティングされた5ミリリットルポリプロピレン50μmのフィルターを用いてフィルタセル。 </li><li>バッファをソート1-2 mlの広範囲にフィルターを洗ってください。 </li><li> 図1に詳述ゲーティング方式以下の488 nmレーザーを搭載したセルソーターを使用してソート固定生殖細胞は、以前に氷の上のセクション1でコーティングされた5ミリリットルポリプロピレン丸底チューブ内の精製画分を収集します。 <ol><li> FBSの100〜200μlのが管壁に選別された細胞の付着を回避するために、コレクションチューブに保たれていることを確認します。 </li><li> SYTO16の濃度が仕分け期間中に蛍光の変動を回避するために飽和していることを確認します。仕分けグラフィックでアレクサフルオロ488パラメータ（DNA染色）での細胞染色強度のさらなる変化がない場合SYTO16が飽和しています。必要に応じて、1μlを添加します飽和状態に達するまでの仕分けチューブにSYTO16。 </li><li>アレクサフルオロ488-A VSイベントの数：次のパラメータを表示し、グラフィック上の総イベントを表示します。 </li><li> 図1に示すように、ゲート1の正DNA染色細胞を選択します。 <ol><li>パラメータとしてFSC-A対SSC-Aを使用してグラフィック上にゲート1から表示セル<ol><li> 図1に示したように、ゲート2でセルを選択します。 </li><li>パラメータとしてアレクサフルオロ488-A対FSC-Aを使用してグラフィック上にゲート2から表示セル。 </li><li> 図1に示したように、ゲート2のグラフィックの上にゲート5とゲート6とセルを選択します。 </li><li>パラメータとしてアレクサフルオロ488-A対アレクサフルオロ488-Wを使用してグラフィックに表示され、別々にゲート5及びゲート6。 </li><li>選択して精子形成は、図1に示したように、ゲート5グラフィックと精子は、ゲート6グラフィックスに10-12精子細胞をステップに1-9精子細胞を繰り返します。 </li></ol></li><li>表示パラメータとしてアレクサフルオロ488-A対FSC-Aを使用してグラフィック上にゲート1からの細胞<ol><li> 図1に示したように、ゲート3とゲート4とのセルを選択します。 </li><li>パラメータとしてアレクサフルオロ488-A対アレクサフルオロ488-Wを使用してグラフィックスの表示を別々ゲート3とゲート4。 </li><li>選択して精子形成は、図1に示したように、ゲート3のグラフィックと精子は、ゲート4のグラフィックに15-16精子細胞を、手順に13-14精子細胞を繰り返します。 </li></ol></li></ol></li></ol></li></ol>

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G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Caspase+activation+throughout+the+first+wave+of+spermatogenesis+in+the+rat.">Caspase activation throughout the first wave of spermatogenesis in the rat.</a> Cell Tissue Res. 325 (3), 533-540 (2006).</li><li>Meistrich, M. L., Trostle-Weige, P. K., Van Beek, M. E. <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+specific+stages+of+spermatids+from+vitamin+A-synchronized+rat+testes+for+assessment+of+nucleoprotein+changes+during+spermiogenesis.">Separation of specific stages of spermatids from vitamin A-synchronized rat testes for assessment of nucleoprotein changes during spermiogenesis.</a> Biol. Reprod. 51 (2), 334-344 (1994).</li><li>van Pelt, A. M., de Rooij, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synchronization+of+the+seminiferous+epithelium+after+vitamin+A+replacement+in+vitamin+A-deficient+mice.">Synchronization of the seminiferous epithelium after vitamin A replacement in vitamin A-deficient mice.</a> Biol. Reprod. 43, 363-367 (1990).</li><li>Getun, I. V., Torres, B., Bois, P. R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flow+cytometry+purification+of+mouse+meiotic+cells.">Flow cytometry purification of mouse meiotic cells.</a> J. Vis. Exp. , (2011).</li><li>Kovtun, I. V., McMurray, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trinucleotide+expansion+in+haploid+germ+cells+by+gap+repair.">Trinucleotide expansion in haploid germ cells by gap repair.</a> Nature Genet. 27 (4), 407-411 (2001).</li><li>Bastos, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=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 (1), 40-49 (2005).</li><li>Lassalle, B., Ziyyat, A., Testart, J., Finaz, C., Lef&#232;vre, A. <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+method+to+isolate+round+spermatids+from+mouse+testis.">Flow cytometric method to isolate round spermatids from mouse testis.</a> Hum. Reprod. 14 (2), 388-394 (1999).</li></ol>

The authors declare no competing financial interests.

精子形成細胞は常に精上皮の複雑さだけでなく、in vitro培養の限られた成功を与えて研究する挑戦されています。長年にわたり、様々な種から生殖細胞を精製するための多くの手法が開発されました。パーコールまたはウシ血清アルブミン勾配で重力を用いて沈降精製技術は通常、無傷の胚細胞の良好な収率を提供するが、このような減数分裂四倍体細胞および精子細胞10のよ?...

Haploid round spermatids differentiate into spermatozoa by a process called spermiogenesis. This involves many different steps including the acquisition of a flagellum, chromatin and cytoskeleton remodeling, condensation of the nucleus as well as the loss of most of the cytoplasm. These unique cellular events must be finely regulated in order to produce a mature functional gamete with an intact genome suitable for fertilization. Spermiogenesis can hardly be studied in vitro since no reliable cell culture system has so far been able to support progression through the different steps of the process. Moreover, actual in vitro techniques lead to a poor yield1,2. In vivo, proper transitions through the different steps of spermiogenesis are crucial for the natural functional integrity of the male gamete. Successful purification of spermatids according to their differentiation steps has never been accomplished with a level of enrichment sufficient to allow molecular characterization of spermiogenesis. For instance, purification of key steps of the spermatidal differentiation would be especially useful to study the developing acrosome, formation of the midpiece3, cell junction dynamics4, RNA dynamics5, chromatin remodeling process6,7 or genomic stability8. Purification of spermatids has been hampered by their progressive morphological transformation, the lack of known stage-specific external biomarkers, and their peculiar shape and size. 
Although most male germ cells display a direct relationship between DNA staining and ploidy (DNA content), we noticed that such positive correlation is no longer applicable to spermatids. This stems from our early observation that seminiferous tubule sections show variable intensity of DNA staining throughout the different spermiogenesis steps. Although DNA staining is consistent with their haploid set of chromosomes from spermiogenesis steps 1 to 7 (round spermatids), we observed a sharp increase in fluorescence intensity with DAPI or SYTO 16 around the onset of nuclear reorganization and chromatin remodeling (spermiogenesis step 8) reaching a peak at the onset of nuclear condensation (spermiogenesis steps 11-12). Following condensation of the nucleus, DNA staining intensity decreases until spermiation (spermiogenesis step 16). We surmised that this was likely associated with the formation of their peculiar chromatin structure transition where histones are replaced by protamines. We therefore developed a reliable flow cytometry method that allows the separation of spermatids using the variation of DNA intensity of spermatids as a main selection parameter.
A simple flow cytometry approach is described to separate mouse spermatids with high purity (95-100%) based on their apparent DNA content (SYTO16 staining), size and granulosity. Spermatids are separated into four populations; spermiogenesis steps 1-9, 10-12, 13-14 and 15-16. Purified spermatids are suitable for genetic/genomic analysis, as well as proteomic applications as described in a recent publication from our group9.

<table border="0" cellpadding="0" cellspacing="0" width="565">
	<tbody>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">Isoflurane</td>
			<td style="width:119px;">ABBOT</td>
			<td style="width:129px;">05260-05</td>
			<td style="width:184px;">For mouse anesthesia before euthanasia</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">Fetal bovine serum</td>
			<td style="width:119px;">Wisent</td>
			<td style="width:129px;">90150</td>
			<td style="width:184px;">For tube coating</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:135px;">1X PBS</td>
			<td style="width:119px;"></td>
			<td style="width:129px;"></td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">EDTA</td>
			<td style="width:119px;">BioShop</td>
			<td style="width:129px;">EDT</td>
			<td style="width:184px;">For sorting buffer preparation</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">HEPES</td>
			<td style="width:119px;">Sigma</td>
			<td style="width:129px;">H</td>
			<td style="width:184px;">For sorting buffer preparation</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">100 % Ethanol</td>
			<td style="width:119px;">Les alcools de commerce</td>
			<td style="width:129px;">092-09-11N</td>
			<td style="width:184px;">For cell fixation</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">SYTO 16</td>
			<td style="width:119px;">Life Technologies</td>
			<td style="width:129px;">S7578</td>
			<td style="width:184px;">DNA staining</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:135px;">5 ml polypropylene round bottom tubes</td>
			<td style="width:119px;">BD Falcon</td>
			<td style="width:129px;">352063</td>
			<td style="width:184px;">Sorted cells collection</td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:135px;">15 ml polypropylene conical bottom tubes</td>
			<td style="width:119px;">PROgene</td>
			<td style="width:129px;">1500</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="81">
			<td height="81" style="height:81px;width:135px;">50 ml polypropylene conical bottom tubes</td>
			<td style="width:119px;">PROgene</td>
			<td style="width:129px;">5000</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:135px;">TEC4 anaesthetic vaporizer</td>
			<td style="width:119px;">Ohmeda</td>
			<td style="width:129px;">1160526</td>
			<td style="width:184px;">For mouse euthanasia</td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;width:135px;">CO2 gas tank</td>
			<td style="width:119px;">Praxair</td>
			<td style="width:129px;">C799117902</td>
			<td style="width:184px;">For mouse euthanasia</td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;width:135px;">O2 gas tank</td>
			<td style="width:119px;">Praxair</td>
			<td style="width:129px;">O254130501</td>
			<td style="width:184px;">For mouse euthanasia</td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:135px;">Homemade mouse gas chamber</td>
			<td style="width:119px;"></td>
			<td style="width:129px;"></td>
			<td style="width:184px;">For mouse euthanasia</td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">40 &#181;m Falcon cell strainer</td>
			<td style="width:119px;">Corning Incorporated</td>
			<td style="width:129px;">352340</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">50-micron sample line filters</td>
			<td style="width:119px;">BD Biosciences</td>
			<td style="width:129px;">649049</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:135px;">Vortex mixer</td>
			<td style="width:119px;">Labnet international, inc.</td>
			<td style="width:129px;">S0200</td>
			<td style="width:184px;">For cell fixation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:135px;">Dynac centrifuge</td>
			<td style="width:119px;">Clay Adams</td>
			<td style="width:129px;">101</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="41">
			<td height="41" style="height:41px;width:135px;">Celltrics 50 &#181;m filters</td>
			<td style="width:119px;">Partec</td>
			<td style="width:129px;">04-004-2327</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="61">
			<td height="61" style="height:61px;width:135px;">488 nm laser-euipped cell sorter</td>
			<td style="width:119px;">BD Biosciences</td>
			<td style="width:129px;">FACSAria III</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;width:135px;">Accudop Fluorescent Beads</td>
			<td style="width:119px;">BD Biosciences</td>
			<td style="width:129px;">345249</td>
			<td style="width:184px;"></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:135px;">Sorting Buffer: 1X PBS, 1mM EDTA pH 8.0, 25mM HEPES pH 7.0, 1%FBS</td>
			<td></td>
			<td></td>
			<td style="width:184px;">FBS is heat-inactivated. Make fresh solution, 0.22 &#956;m filtered and keep at 4&#176;C.</td>
		</tr>
	</tbody>
</table>

step-specific sorting of mouse spermatids by flow cytometry

マウスの精子細胞の分化は、無傷のゲノムと機能的雄性配偶子の製造のための1つの重要なプロセスは、次の世代に伝達されます。これまでのところ、この形態転移の分子研究はその後の分析のために精子細胞分化のこれらの重要なステップの適切な分離を可能にする方法の欠如によって妨げられてきました。フローサイトメトリーを使用して、これらの細胞の適切なゲーティングでの初期の試みが原因クロマチンリモデリングを受けて精子細胞におけるDNA蛍光の独特の増加のために困難であったかもしれません。この観察に基づいて、我々は、エタノールで固定したマウス精子の4集団、核リモデリングプロセスに異なる状態を表す各の再現性精製を可能にする、シンプルなフローサイトメトリー方式の詳細を提供します。人口濃縮は段階特異的なマーカーおよび形態学的規準を用いて確認されています。精製された精子細胞は、ゲノムやプロテオームのために使用することができますIC分析します。

フローサイトメトリーで使用されるゲーティング戦略 図1は、4つの高純度の精子細胞集団をソートするフローサイトメトリーに使用されるゲート戦略を表します。簡単に言うと、正のDNA染色を有する細胞（アレクサフルオロ488-A）が第1のサイズ対granulosity（SSC-A）を示すドットプロットで精子から1精子細胞は?...

Watch this Scientific Journal Video about Step-specific Sorting of Mouse Spermatids by Flow Cytometry at JoVE.com

Step-specific Sorting of Mouse Spermatids by Flow Cytometry

We describe a sorting strategy for mouse spermatids using flow cytometry. Spermatids are sorted into four highly pure populations, including round (spermiogenesis steps 1-9), early elongating (spermiogenesis steps 10-12), late elongating (spermiogenesis steps 13-14) and elongated spermatids (spermiogenesis steps 15-16). DNA staining, size and granulosity are used as selection parameters.

フローサイトメトリーによるマウス精子細胞のステップ固有のソート

The differentiation of mouse spermatids is one critical process for the production of a functional male gamete with an intact genome to be transmitted to ...

step-specific-sorting-of-mouse-spermatids-by-flow-cytometry

Research

JoVE Journal

Developmental Biology

10.4K ビュー.  Université de Sherbrooke. We describe a sorting strategy for mouse spermatids using flow cytometry. Spermatids are sorted into four highly pure populations, including round (spermiogenesis steps 1-9), early elongating (spermiogenesis steps 10-12), late elongating (spermiogenesis steps 13-14) and elongated spermatids (spermiogenesis steps 15-16). DNA staining, size and granulosity are used as selection parameters.

ビデオ: Step-specific Sorting of Mouse Spermatids by Flow Cytometry

Identification Of Erythromyeloid Progenitors And Their Progeny In The Mouse Embryo By Flow Cytometry

Macrophages are professional phagocytes from the innate arm of the immune system. In steady-state, sessile macrophages are found in adult tissues where they act as front line sentinels of infection and tissue damage. While other immune cells are continuously renewed from hematopoietic stem and progenitor cells (HSPC) located in the bone marrow, a lineage of macrophages, known as resident macrophages, have been shown to be self-maintained in tissues without input from bone marrow HSPCs. This lineage is exemplified by microglia in the brain, Kupffer cells in the liver and Langerhans cells in the epidermis among others. The intestinal and colon lamina propria are the only adult tissues devoid of HSPC-independent resident macrophages. Recent investigations have identified that resident macrophages originate from the extra-embryonic yolk sac hematopoiesis from progenitor(s) distinct from fetal hematopoietic stem cells (HSC). Among yolk sac definitive hematopoiesis, erythromyeloid progenitors (EMP) give rise both to erythroid and myeloid cells, in particular resident macrophages. EMP are only generated within the yolk sac between E8.5 and E10.5 days of development and they migrate to the fetal liver as early as circulation is connected, where they expand and differentiate until at least E16.5. Their progeny includes erythrocytes, macrophages, neutrophils and mast cells but only EMP-derived macrophages persist until adulthood in tissues. The transient nature of EMP emergence and the temporal overlap with HSC generation renders the analysis of these progenitors difficult. We have established a tamoxifen-inducible fate mapping protocol based on expression of the macrophage cytokine receptor Csf1r promoter to characterize EMP and EMP-derived cells in vivo by flow cytometry.

While infiltrating macrophages are continuously recruited to adult tissues from circulating precursors, resident macrophages seed their tissue during development, where they are maintained without further input from progenitors. The progenitors for resident macrophages were recently identified. Here, we present methods for the genetic fate mapping of the resident macrophage progenitors.

フローサイトメトリーによるマウス胚における赤血球系前駆細胞およびその子孫の同定

Macrophages are professional phagocytes from the innate arm of the immune system. In steady-state, sessile macrophages are found in adult tissues where ...

発生生物学

Isolating and Analyzing Cells of the Pancreas Mesenchyme by Flow Cytometry

The pancreas is comprised of epithelial cells that are required for food digestion and blood glucose regulation. Cells of the pancreas microenvironment, including endothelial, neuronal, and mesenchymal cells were shown to regulate cell differentiation and proliferation in the embryonic pancreas. In the adult, the function and mass of insulin-producing cells were shown to depend on cells in their microenvironment, including pericyte, immune, endothelial, and neuronal cells. Lastly, changes in the pancreas microenvironment were shown to regulate pancreas tumorigenesis. However, the cues underlying these processes are not fully defined. Therefore, characterizing the different cell types that comprise the pancreas microenvironment and profiling their gene expression are crucial to delineate the tissue development and function under normal and diseased states. Here, we describe a method that allows for the isolation of mesenchymal cells from the pancreas of embryonic, neonatal, and adult mice. This method utilizes the enzymatic digestion of mouse pancreatic tissue and the subsequent fluorescence-activated cell sorting (FACS) or flow-cytometric analysis of labeled cells. Cells can be labeled by either immunostaining for surface markers or by the expression of fluorescent proteins. Cell isolation can facilitate the characterization of genes and proteins expressed in cells of the pancreas mesenchyme. This protocol was successful in isolating and culturing highly enriched mesenchymal cell populations from the embryonic, neonatal, and adult mouse pancreas.

Here, we describe a method for the isolation of cells in the pancreas microenvironment from embryonic, neonatal and adult mouse tissue, focusing on the isolation of mesenchymal cells. This method allows profiling of cell gene expression and protein secretion in order to elucidate the extrinsic signals that regulate pancreas development, function, and tumorigenesis.

フローサイトメトリーによる膵臓間葉の細胞を単離と解析

The pancreas is comprised of epithelial cells that are required for food digestion and blood glucose regulation. Cells of the pancreas microenvironment, ...

A Standardized Approach for Multispecies Purification of Mammalian Male Germ Cells by Mechanical Tissue Dissociation and Flow Cytometry

Fluorescence-activated cell sorting (FACS) has been one of the methods of choice to isolate enriched populations of mammalian testicular germ cells. Currently, it allows the discrimination of up to 9 murine germ cell populations with high yield and purity. This high-resolution in discrimination and purification is possible due to unique changes in chromatin structure and quantity throughout spermatogenesis. These patterns can be captured by flow cytometry of male germ cells stained with fluorescent DNA-binding dyes such as Hoechst-33342 (Hoechst). Herein is a detailed description of a recently developed protocol to isolate mammalian testicular germ cells. Briefly, single cell suspensions are generated from testicular tissue by mechanical dissociation, double stained with Hoechst and propidium iodide (PI) and processed by flow cytometry. A serial gating strategy, including the selection of live cells (PI negative) with different DNA content (Hoechst intensity), is used during FACS sorting to discriminate up to 5 germ cell types. These include, with corresponding average purities (determined by microscopy evaluation): spermatogonia (66%), primary (71%) and secondary (85%) spermatocytes, and spermatids (90%), further separated into round (93%) and elongating (87%) subpopulations. Execution of the entire workflow is straightforward, allows the isolation of 4 cell types simultaneously with the appropriate FACS machine, and can be performed in less than 2 h. As reduced processing time is crucial to preserve the physiology of ex vivo cells, this method is ideal for downstream high-throughput studies of male germ cell biology. Moreover, a standardized protocol for multispecies purification of mammalian germ cells eliminates methodological sources of variables and allows a single set of reagents to be used for different animal models.

This work describes the standardization of a method to obtain purified germ cell populations from testicular tissue of different mammalian species. It is a straightforward protocol that combines mechanical testis dissociation, staining with Hoechst-33342 and propidium iodide, and FACS sorting, with wide applications in comparative studies of male reproductive biology.

機械的組織解離およびフローサイトメトリーによる哺乳動物雄胚細胞のマルチシード精製のための標準的アプローチ

Fluorescence-activated cell sorting (FACS) has been one of the methods of choice to isolate enriched populations of mammalian testicular germ cells. ...

Use of Hematopoietic Stem Cell Transplantation to Assess the Origin of Myelodysplastic Syndrome

Myelodysplastic syndromes (MDS) are a diverse group of hematopoietic stem cell disorders that are defined by ineffective hematopoiesis, peripheral blood cytopenias, dysplasia, and a propensity for transformation to acute leukemia. NUP98-HOXD13 (NHD13) transgenic mice recapitulate human MDS in terms of peripheral blood cytopenias, dysplasia, and transformation to acute leukemia. We previously demonstrated that MDS could be transferred from a genetically engineered mouse with MDS to wild-type recipients by transplanting MDS bone marrow nucleated cells (BMNC). To more clearly understand the MDS cell of origin, we have developed approaches to transplant specific, immunophenotypically defined hematopoietic subsets. In this article, we describe the process of isolating and transplanting specific populations of hematopoietic stem and progenitor cells. Following transplantation, we describe approaches to assess the efficiency of transplantation and persistence of the donor MDS cells.

We describe the use of hematopoietic stem cell transplantation (HSCT) to assess the malignant potential of genetically engineered hematopoietic cells. HSCT is useful for evaluating various malignant hematopoietic cells in vivo as well as generating a large cohort of mice with myelodysplastic syndromes (MDS) or leukemia to evaluate novel therapies.

骨髄異形成症候群の起源を評価するために造血幹細胞移植の使用

Myelodysplastic syndromes (MDS) are a diverse group of hematopoietic stem cell disorders that are defined by ineffective hematopoiesis, peripheral blood ...

Real-time Live-cell Flow Cytometry to Investigate Calcium Influx, Pore Formation, and Phagocytosis by P2X7 Receptors in Adult Neural Progenitor Cells

Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a method whereby live-cell flow cytometry is extended upon to analyze the multiple functions of P2X7 receptor activation in real-time. Using a time module installed on a flow cytometer, live-cell functionality can be assessed and plotted over a given time period to explore the kinetics of calcium influx, transmembrane pore formation, and phagocytosis. This simple method is advantageous as all three canonical functions of the P2X7 receptor can be assessed using one machine, and the gathered data plotted over time provides information on the entire live-cell population rather than single-cell recordings often obtained using technically challenging patch-clamp methods. Calcium influx experiments use a calcium indicator dye, while P2X7 pore formation assays rely on ethidium bromide being allowed to pass through the transmembrane pore formed upon high agonist concentrations. Yellow-green (YG) latex beads are utilized to measure phagocytosis. Specific agonists and antagonists are applied to investigate the effects of P2X7 receptor activity. Individually, these methods can be modified to provide quantitative data on any number of calcium channels and purinergic and scavenger receptors. Taken together, they highlight how the use of real-time live-cell flow cytometry is a rapid, cost-effective, reproducible, and quantifiable method to investigate P2X7 receptor function.

Providing single-cell sensitivity, real-time flow cytometry is uniquely suited to quantify multimodal receptor functions of live cultures. Using adult neural progenitor cells, the P2X7 receptor function was assessed via calcium influx detected by calcium indicator dye, transmembrane pore formation by ethidium bromide uptake, and phagocytosis using fluorescent latex beads.

大人の神経前駆細胞における P2X7 受容体を貪食、細孔の形成、カルシウム流入を調査するためのリアルタイム生細胞フローサイトメトリー

Live-cell flow cytometry is increasingly used among cell biologists to quantify biological processes in a living cell culture. This protocol describes a ...

Isolation and Staining of Mouse Skin Keratinocytes for Cell Cycle Specific Analysis of Cellular Protein Expression by Mass Cytometry

The goal of this protocol is to detect and quantify protein expression changes in a cell cycle-dependent manner using single cells isolated from the epidermis of mouse skin. There are seven important steps: separation of the epidermis from the dermis, digestion of the epidermis, staining of the epidermal cell populations with cisplatin, sample barcoding, staining with metal tagged antibodies for cell cycle markers and proteins of interest, detection of metal-tagged antibodies by mass cytometry, and the analysis of expression in the various cell cycle phases. The advantage of this approach over histological methods is the potential to assay the expression pattern of &#62;40 different markers in a single cell at different phases of the cell cycle. This approach also allows for the multivariate correlation analysis of protein expression that is more quantifiable than histological/imaging methods. The disadvantage of this protocol is that a suspension of single cells is needed, which results in the loss of location information provided by the staining of tissue sections. This approach may also require the inclusion of additional markers to identify different cell types in crude cell suspensions. The application of this protocol is evident in the analysis of hyperplastic skin disease models. Moreover, this protocol can be adapted for the analysis of specific sub-type of cells (e.g., stem cells) by the addition of lineage-specific antibodies. This protocol can also be adapted for the analysis of skin cells in other experimental species.

This protocol describes how to isolate skin keratinocytes from mouse models, to stain with metal-tagged antibodies, and to analyze stained cells by mass cytometry in order to profile the expression pattern of proteins of interest in the different cell cycle phases.

質量細胞血症による細胞タンパク質発現の細胞周期特異的解析におけるマウス皮膚ケラチノサイトの単離と染色

The goal of this protocol is to detect and quantify protein expression changes in a cell cycle-dependent manner using single cells isolated from the ...

Enrichment of Pachytene Spermatocytes and Spermatids from Mouse Testes Using Standard Laboratory Equipment

To characterize each step of spermatogenesis, researchers must separate different subpopulations of germ cells from testes. However, isolating discrete populations is challenging, because the adult testis contains a complex mix of germ cells from all steps of spermatogenesis along with certain populations of somatic cells. Over the past few decades, different techniques such as centrifugal elutriation, fluorescence-activated cell sorting (FACS), and STA-PUT have been successfully applied to the isolation of germ cells. A drawback is that they all require dedicated devices and specialized training. Following principles underlying the STA-PUT method, a simple protocol has been developed for the isolation of pachytene spermatocytes, round spermatids, and elongating spermatids from mouse testes. After preparing a single cell suspension of testicular cells, specific cell populations are enriched by gravity sedimentation through a discontinuous bovine serum albumin (BSA) density gradient. The cell fractions are then manually collected and microscopically analysed. This modified density gradient for round spermatids (MDR) sedimentation protocol can be widely applied, because it requires only standard laboratory equipment. Furthermore, the protocol requires minimal starting materials, reducing its cost and use of laboratory animals.

Presented here is a protocol for enriching pachytene spermatocytes, round spermatids, and elongating spermatids from adult mouse testes using a discontinuous bovine serum albumin density gradient with standard laboratory equipment.

標準的な実験装置を用いてマウス精巣からパチテン精子細胞と精子を濃縮

To characterize each step of spermatogenesis, researchers must separate different subpopulations of germ cells from testes. However, isolating discrete ...

Using Flow Cytometry to Detect and Quantitate Altered Blood Formation in the Developing Zebrafish

The diversity of cell lineages that comprise mature blood in vertebrate animals arise from the differentiation of hematopoietic stem and progenitor cells (HSPCs). This is a critical process that occurs throughout the lifespan of organisms, and disruption of the molecular pathways involved during embryogenesis can have catastrophic long-term consequences. For a multitude of reasons, zebrafish (Danio rerio) has become a model organism to study hematopoiesis. Zebrafish embryos develop externally, and by 7 days postfertilization (dpf) have produced most of the subtypes of definitive blood cells that will persist for their lifetime. Assays to assess the number of hematopoietic cells have been developed, mainly utilizing specific histological stains, in situ hybridization techniques, and microscopy of transgenic animals that utilize blood cell-specific promoters driving the expression of fluorescent proteins. However, most staining assays and in situ hybridization techniques do not accurately quantitate the number of blood cells present; only large differences in cell numbers are easily visualized. Utilizing transgenic animals and analyzing individuals with fluorescent or confocal microscopy can be performed, but the quantitation of these assays relies on either counting manually or utilizing expensive imaging software, both of which can make errors. Development of additional methods to assess blood cell numbers would be economical, faster, and could even be automated to quickly assess the effect of CRISPR-mediated genetic modification, morpholino-mediated transcript reduction, and the effect of drug compounds that affect hematopoiesis on a large scale. This novel assay to quantitate blood cells is performed by dissociating whole zebrafish embryos and analyzing the amount of fluorescently labelled blood cells present. These assays should allow elucidation of molecular pathways responsible for blood cell generation, expansion, and regulation during embryogenesis, which will allow researchers to further discover novel factors altered during blood diseases, as well as pathways essential during the evolution of vertebrate hematopoiesis.

This assay is a simple method to quantitate hematopoietic cells in developing embryonic zebrafish. Blood cells from dissociated zebrafish are subjected to flow cytometry analysis. This allows the detection of blood defects in mutant animals and after genetic modification.

発達中のゼブラフィッシュにおける変化した血液形成を検出し定量するためのフローサイトメトリーの使用

The diversity of cell lineages that comprise mature blood in vertebrate animals arise from the differentiation of hematopoietic stem and progenitor cells ...

FACS-Isolation and Culture of Fibro-Adipogenic Progenitors and Muscle Stem Cells from Unperturbed and Injured Mouse Skeletal Muscle

Fibro-adipogenic progenitor cells (FAPs) are a population of skeletal muscle-resident mesenchymal stromal cells (MSCs) capable of differentiating along fibrogenic, adipogenic, osteogenic, or chondrogenic lineage. Together with muscle stem cells (MuSCs), FAPs play a critical role in muscle homeostasis, repair, and regeneration, while actively maintaining and remodeling the extracellular matrix (ECM). In pathological conditions, such as chronic damage and muscular dystrophies, FAPs undergo aberrant activation and differentiate into collagen-producing fibroblasts and adipocytes, leading to fibrosis and intramuscular fatty infiltration. Thus, FAPs play a dual role in muscle regeneration, either by sustaining MuSC turnover and promoting tissue repair or contributing to fibrotic scar formation and ectopic fat infiltrates, which compromise the integrity and function of the skeletal muscle tissue. A proper purification of FAPs and MuSCs is a prerequisite for understanding the biological role of these cells in physiological as well as in pathological conditions. Here, we describe a standardized method for the simultaneous isolation of FAPs and MuSCs from limb muscles of adult mice using fluorescence-activated cell sorting (FACS). The protocol describes in detail the mechanical and enzymatic dissociation of mononucleated cells from whole limb muscles and injured tibialis anterior (TA) muscles. FAPs and MuSCs are subsequently isolated using a semi-automated cell sorter to obtain pure cell populations. We additionally describe an optimized method for culturing quiescent and activated FAPs and MuSCs, either alone or in coculture conditions.

The precise identification of fibro-adipogenic progenitor cells (FAPs) and muscle stem cells (MuSCs) is critical to studying their biological function in physiological and pathological conditions. This protocol provides guidelines for the isolation, purification, and culture of FAPs and MuSCs from adult mouse muscles.

FACSによる無動および損傷マウス骨格筋からの線維脂肪原性前駆細胞および筋幹細胞の単離および培養

Fibro-adipogenic progenitor cells (FAPs) are a population of skeletal muscle-resident mesenchymal stromal cells (MSCs) capable of differentiating along ...

Identification and Isolation of Burst-Forming Unit and Colony-Forming Unit Erythroid Progenitors from Mouse Tissue by Flow Cytometry

Early erythroid progenitors were originally defined by their colony-forming potential in vitro and classified into burst-forming and colony-forming &#34;units&#34; known as BFU-e and CFU-e. Until recently, methods for the direct prospective and complete isolation of pure BFU-e and CFU-e progenitors from freshly isolated adult mouse bone marrow were not available. To address this gap, a single-cell RNA-seq (scRNAseq) dataset of mouse bone marrow was analyzed for the expression of genes coding for cell surface markers. This analysis was combined with cell fate assays, allowing the development of a novel flow cytometric approach that identifies and allows the isolation of complete and pure subsets of BFU-e and CFU-e progenitors in mouse bone marrow or spleen. This approach also identifies other progenitor subsets, including subsets enriched for basophil/mast cell and megakaryocytic potentials. The method consists of labeling fresh bone marrow or spleen cells with antibodies directed at Kit and CD55. Progenitors that express both these markers are then subdivided into five principal populations. Population 1 (P1 or CFU-e, Kit+ CD55+ CD49fmed/low CD105med/high CD71med/high) contains all of the CFU-e progenitors and may be further subdivided into P1-low (CD71med CD150high) and P1-hi (CD71high CD150low), corresponding to early and late CFU-e, respectively; Population 2 (P2 or BFU-e, Kit+ CD55+ CD49fmed/low CD105med/high CD71low CD150high) contains all of the BFU-e progenitors; Population P3 (P3, Kit+ CD55+ CD49fmed/high CD105med/low CD150low CD41low) is enriched for basophil/mast cell progenitors; Population 4 (P4, Kit+ CD55+ CD49fmed/high CD105med/low CD150high CD41+) is enriched for megakaryocytic progenitors; and Population 5 (P5, Kit+ CD55+ CD49fmed/high CD105med/low CD150high CD41-) contains progenitors with erythroid, basophil/mast cell, and megakaryocytic potential (EBMP) and erythroid/ megakaryocytic/ basophil-biased multipotential progenitors (MPPs). This novel approach allows greater precision when analyzing erythroid and other hematopoietic progenitors and also allows for reference to transcriptome information for each flow cytometrically defined population.

Here, we describe a novel flow cytometric method for prospective isolation of early burst-forming unit erythroid (BFU-e) and colony-forming unit erythroid (CFU-e) progenitors directly from fresh mouse bone marrow and spleen. This protocol, developed based on single-cell transcriptomic data, is the first to isolate all the tissue's erythroid progenitors with high purity.

フローサイトメトリーによるマウス組織からのバースト形成ユニットおよびコロニー形成ユニット赤血球前駆細胞の同定と単離(英語)

Early erythroid progenitors were originally defined by their colony-forming potential in vitro and classified into burst-forming and colony-forming ...