This work was supported by the Seed Grant Award from California Northstate University College of Pharmacy (to AMN). The authors would like to thank California Northstate University College of Pharmacy for covering the publication cost of this article, and George Talbott for his help in editing this manuscript.

のCaco-2細胞の1メンテナンス<ol><li>正規の組織培養皿を用いて、 <ol><li> 37℃の水浴中にバイアルを配置することによって、凍結バイアルからのCaco-2細胞を解凍し、直ちに予め温めた増殖培地（15％ウシ胎児血清（FBS、10 mlを含む10cmの組織培養皿に追加））ダルベッコ改変イーグル培地（DMEM）で。 <ol><li> （15分間）、それらが分離されるまで、37℃で0.05％3mlのトリプシン/ 0.53 mMのエチレンジアミン四酢酸（EDTA）で細胞をインキュベートすることにより、6：たCaco-2細胞は、50〜70％コンフルエンスに達したときに、それらを1分割。細胞凝集を回避するために、穏やかなピペッティングにより細胞を数回混ぜます。予熱した増殖培地10 mlを入れた10cmの組織培養皿にトリプシン処理した細胞を0.5mlを加えます。 </li></ol></li><li>静かに左右方向に続く前後方向に皿を数回振ります。料理を旋回しないでくださいように、不等細胞分散をもたらすことができます。 </li><li> 5％CO 2を供給し、37℃のインキュベーターで平らな面に皿を置きます。傾斜面は、また、不等細胞分散をもたらすことができます。 </li><li>インキュベーションを開始した後、増殖培地1日を変更します。 </li><li>細胞を監視し、それらがコンフルエンスに達する日を記録。細胞は、それらが分割された日から合流点に到達するのは約1週間かかります。 </li><li>細胞がコンフルエンスに到達する前に週に二度、増殖培地を変更します。細胞がコンフルエンスに達した後は、一日おきに成長培地を変更します。細胞は、7日後にコンフルエントになったら、毎日の成長培地を変更します。 注：彼らは13日後コンフルエント（ 図1）である場合、細胞が実験のための準備ができています。細胞は、最終的にリポタンパク質の生産にあまり有効になりますので、8コンフルエント後の13から17日間の間にあるセルを使用。実験を行う方法については、手順3に進みます。</li></ol></li><li>透過膜システムを使用して<ol><li>ステップ1.1.1.1で説明したように、透過膜インサートでのCaco-2細胞を播種します。上記。その細胞増殖が（回復期）通常遅いため凍結バイアルから細胞を使用しないでください。簡単に説明すると、予め温めた増殖培地の10ミリリットルが含まれている頂端チャンバー（上部コンパートメント）にトリプシン処理した細胞の0.5ミリリットルを追加します。また、基底外側室（下部コンパートメント）に予熱した増殖培地の10ミリリットルを追加します。 注：ベストプラクティスについては、側底チャンバーに最初にして頂端チャンバーに増殖培地を追加します。古いメディアを取り外すときは、頂端メディアの前に側底メディアを削除します。それが膜を破裂としてポリカーボネート膜を突っついは避けてください。 </li><li>によるポリカーボネート膜を介して、悪い細胞の可視性のために、同様の密度との定期的な組織培養皿中のCaco-2細胞を播種すると、細胞コンフルエンスを判断するためにこの料理を使用しています。 </li><li>のフォローTEPS上記1.1.2-1.1.6。 </li></ol></li></ol> 2.遺伝子の過剰発現<ol><li>定期的なトランスフェクション法を用いて、 <ol><li> 1.1.1.1.-1.1.4上記で説明したように組織培養皿上でのCaco-2細胞をシード。 注：細胞が約40〜50％コンフルエントである場合、それらは、トランスフェクトされる準備ができています。 </li><li>マイクロチューブ中の還元血清培地の472μlにトランスフェクション試薬の67μlを添加します。管壁と希釈されていないトランスフェクション試薬との接触を避けてください。 </li><li> pLL3.7の23μgのトランスフェクション試薬/低血清培地混合物に緑色蛍光タンパク質（EGFP）9を強化加えます。 </li><li> RTで20分間混合物をインキュベートします。 </li><li> DMEM、10％FBSの8ミリリットルでのCaco-2細胞の増殖培地を交換してください。 </li><li>滴下皿にDNA /トランスフェクション試薬/縮小血清培地の混合物を追加します。 </li><li>軽く前方およびBaで料理を数回振ります左右方向に続くckward方向。 </li><li> 37℃のインキュベーターで皿を置きます。 </li><li>成長培地10mlのインキュベーションを開始した後の日と皿の中でメディアを交換してください。 </li><li>遺伝子発現を監視します。 <ol><li> 4 &#39;、6-ジアミジノ-2-フェニルインドール（DAPI）染色することなく、遺伝子発現をモニターします。蛍光顕微鏡を使用して、緑である細胞の割合を決定します。パーセンテージは、トランスフェクション効率を表します。 </li><li> DAPI染色と遺伝子発現を監視します。 <ol><li>リン酸緩衝生理食塩水（PBS）で3回細胞を洗浄します。 </li><li> PBS中の4％ホルムアルデヒド（室温で10分間のインキュベーション）を10mlを加えることにより細胞を固定します。 </li><li> PBSで細胞を3回洗浄します。 </li><li> 500 DAPI、1％BSA、0.01％ジギトニン：1を含む8mlのPBSで室温で15分間、暗所で細胞をインキュベートします。 </li><li> PBSで細胞を3回洗浄します。 </li><li> U蛍光顕微鏡を歌う、青色であるものに緑/青の相対的な（ 図2上部パネル）である細胞の数を決定します。計算された割合は、トランスフェクション効率を表します。 </li></ol></li></ol></li></ol></li><li>レンチウイルス過剰発現システム10を使用して<ol><li> 15cmの組織培養皿（それらの増殖培地としてDMEM中10％FBS）中に種子ヒト胚腎臓（HEK）293T細胞。 注：細胞が60〜70％コンフルエントである場合、それらは、トランスフェクトされる準備ができています。 </li><li>マイクロチューブ11に減少血清培地の1,133μlにトランスフェクション試薬の162μlを添加します。管壁と希釈されていないトランスフェクション試薬との接触を避けてください。 </li><li>トランスフェクション試薬/ RにpLL3.7のeGFP（または他の構造物）、のRev応答エレメント（RRE）の15.6μgの、REVの6.0μgの、および水疱性口内炎ウイルス糖タンパク質（VSVG）の8.4μgの24μgのを追加します。析出血清培地混合物。 </li><li> RTで20分間混合物をインキュベートします。 </li><li> DMEM、10％FBSを16 mlの増殖培地を交換してください。 </li><li>滴下皿にDNA /トランスフェクション試薬/縮小血清培地の混合物を追加します。 </li><li>静かに左右方向に続く前後方向に皿を数回振ります。それは、この時点で剥離しHEK293T細胞のいくつかを見るために、通常です。 </li><li>インキュベーターで皿を置きます。 </li><li>インキュベーションの24時間後、増殖培地を25 mlの皿の中でメディアを交換してください。 </li><li>翌日、レンチウイルス（最初のコレクション）を含む増殖培地を収集します。 </li><li>より多くのレンチウイルス（第2集）を収集するための手順を繰り返し2.2.10。 </li><li> （5分間、2,500×gで）第一および第二の収集をプールし、遠心分離により細胞破片を除去。 </li><li>使い捨てボトルトップフィルター（0.45μmの孔）を持つコレクションをフィルタリングし、RT（JA-20ローター）で2時間31,400×gでコレクションを遠心分離することにより、ウイルスを濃縮します。ペレットが配置されている遠心分離管の底部をマーク。上清を除去し、約15分間室温で反転チューブを残します。 </li><li> 1×PBS100μlのウイルス含有ペレットを再懸濁します。泡を避けます。 </li><li> -80℃で濃縮したウイルスを保管してください。凍結融解の繰り返しは避けてください。 </li><li>滴定によってのCaco-2細胞を形質導入するために必要なウイルスの最適量を決定します。コストを節約するために、代わりに滴定のための10cmの組織培養皿の（増殖培地/ウェルの0.3ミリリットル）を24ウェルプレートを使用しています。 <ol><li>濃縮したウイルスの増加量を加える（0、1、2、5、10、25、50μL/ウェル）を40％〜70％コンフルエントのCaco-2細胞へのポリブレン（最終濃度=5μg/ mlの）を補充しました。 1.1.2で説明したように静かに24ウェルプレートを振ります。 </li><li>それらの遺伝子発現（ステップ2.1.10。）（ 図2下のを監視4パネル）。 </li></ol></li><li>導入遺伝子の発現は、一般的に維持されるので、将来の実験のために形質導入​​された細胞を維持し、継続的な遺伝子発現（ステップ2.1.10。）を監視します。 </li></ol></li></ol> 3.リポタンパク質分泌を刺激<ol><li>定期的な組織培養ディッシュを使用して<ol><li>オレイン酸、レシチン40 mg及びタウロコール酸ナトリウム48mgの50mgを混合することにより、100Xの脂質混合物を準備します。 （8皿のための十分な）PBSで900μlにボリュームをもたらします。勢いよく脂質混合物をボルテックスし。 </li><li>増殖培地の89.1ミリリットルに100Xの脂質混合物の900μlを添加します。混合し、脂質含有培地をフィルタリングします。オレイン酸、レシチン、およびタウロコール酸ナトリウムの最終濃度（1×）は、それぞれ2.0ミリメートル、1.36ミリメートル、および1.0 mMです。 </li><li>細胞への脂質含有培地10mlのを追加します。 </li><li> 37で4時間脂質含有培地で細胞を培養しますCのインキュベーターを°。 </li><li> PBSで細胞を3回洗浄します。 </li><li>リポタンパク質の分泌を収集するために、細胞を増殖培地を10mlを加えます。 </li><li> 37℃のインキュベーターで2時間インキュベートします。 </li><li>リポ蛋白質含有培地を収集します。 </li></ol></li><li>透過膜システムを使用して<ol><li>手順に従ってください3.1.1-3.1.2脂質混合物を調製しました。 </li><li>頂端チャンバへの脂質含有培地10ml及び側底チャンバへの成長培地10mlのを追加します。 </li><li> 37℃のインキュベーター内で4時間インキュベートします。基底外側チャンバ内にリポ蛋白質含有培地を収集します。 </li></ol></li></ol> 4.リポタンパク質の分離（図3） <ol><li>遠心分離（5分間2,000×gで）によってリポタンパク質含有培地から細胞破片を除去。 </li><li> 50mlのチューブにメディアをデカントします。 </li><li>メディアへの塩化ナトリウムの5.95グラムを追加します。 </li><li> SAの場合mpleはリポタンパク質の完全性を維持するために1プロテアーゼインヒビターカクテル錠を追加、TEMによって分析されます。 </li><li>水で23ミリリットル（1.2グラム/ mlの濃度のNaCl溶液）にボリュームをもたらします。 </li><li>完全に溶質を溶解させます。 </li><li>ポリカーボネート超遠心管にソリューションのすべてをデカント。 </li><li>ゆっくり水0.5ml（1.0グラム/ mlの濃度）と1.2グラム/ mlの濃度の溶液を重ねます。 </li><li>体積重量ではなく、チューブのバランスをとります。 </li><li>ゆっくりT865ローターにチューブをロードします。 </li><li> 4℃で24時間、429460×gで超遠心機でサンプルをスピン。 </li><li>すぐに穏やかにピペッティングすることによって、トップ0.5ミリリットルの溶液を分離します。できるだけまだチューブを保管してください。 </li></ol> 5. TEM分析<ol><li> 2％リンタングステン酸の5ミリリットル（V / W）を準備し、pHを6.0に調整します。 </li><li>シリンジフィルター（0.2μmの孔サイズ）で2％リンタングステン酸をフィルタリングします。 </li><li>無菌皿にリポタンパク質サンプルの20μlのを削除します。 </li><li>同じ皿に次のサンプルを濾過し、2％リンタングステン酸20μlのを削除します。 </li><li>ゆっくり鈍い側が試料上に載っているとEMグリッドをドロップします。 </li><li> 1分間室温でインキュベートします。 </li><li>ゆっくりグリッドからサンプルを除去するために、濾紙上のEMグリッドの側をタップします。 </li><li>ゆっくり鈍い側は2％リンタングステン酸で休んでEMグリッドをドロップします。 </li><li> 1分間室温でインキュベートします。 </li><li>ゆっくりグリッドからリン酸を除去し、濾紙上のEMグリッドの側をタップします。 </li><li> TEMを使用して、リポタンパク質（ 図4）の画像を取り込みます。 </li></ol>

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The author has nothing to disclose.

この論文では、使用できる2つのシステムは、Caco-2細胞は、すな​​わち、正規の組織培養皿や透過膜に記載されている維持します。透過膜システムを使用する利点は、頂端の分離および基底外側コンパートメント、および脂質混合物をインキュベートし、同時にリポタンパク質分泌を収集する能力を含みます。しかし、透過膜インサートは高価であり、それらのポリカーボネート膜は、良好...

4 -食事脂肪の腸管吸収に関する研究、および脂溶性薬物とビタミンは、リンパ瘻モデル1を用いて、in vivoで行うことができます。しかし、関連する外科技術は、困難でなく、高価なだけでなく、です。糞便分析に基づいて、in vivoでのアプローチを利用することができるが、それらは、胃腸管2,5パーセントの取り込みを決定するために主に使用されています。この論文に記載のin vitroモデルは、よりコスト効果的であり、関係する技術は、おそらくあまり挑 ​​戦しています。遺伝的修飾研究は、時間がかかり、それらは、このin vitroモデルを使用して行われる場合に、より経済的かつ少ないです。 腸細胞によって取り込まれる脂溶性物質は、リポタンパク質6,7にパッケージ化されているので、リポタンパク質を生成するために、このin vitroモデルの有効性が重要です。二つの主要なintestinaLのリポタンパク質は、カイロミクロン及び超低密度リポタンパク質（VLDL）です。脂質は、胃腸内腔に豊富に存在する場合、直径が80nm以上とリポタンパク質として定義されるキロミクロンは、小腸により厳密に製造されています。彼らは最大のリポタンパク質であるため、カイロミクロンは考えられる最も効率的な脂質トランスポーターです。カイロミクロン8を生成することができる。このインビトロモデルは、食事の脂肪吸収、消化管による脂溶性ビタミンの吸収、および親油性薬物の経口バイオアベイラビリティを研究するために使用することができます。リポタンパク質画分中の脂溶性分子、ビタミン、または薬物の存在は、小腸によるその吸収の指標です。前述のように、このモデルは、経口バイオアベイラビリティ、親油性薬剤6を改善するために使用することができます。 本稿では、Caco-2細胞はどのように脂質マイル、透過膜または通常の組織培養皿で維持されるべきである方法を説明しますリポタンパク質の産生を刺激するための固定装置は、レンチウイルス発現系は、効果的な過剰発現を達成するために使用する方法、調製方法、および単離されたリポタンパク質を分析するべきであるべきです。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>DMEM</td>
			<td>VWR</td>
			<td>16750-112</td>
			<td>Pre-warm the growth media in individual tissue culture dish before adding cells</td>
		</tr>
		<tr>
			<td>FBS</td>
			<td>Fisher</td>
			<td>3600511</td>
			<td>We do not heat inactivate our serum</td>
		</tr>
		<tr>
			<td>Trypsin</td>
			<td>VWR</td>
			<td>45000-660</td>
			<td>Cells can be washed with PBS prior to trypsin treatment&#160;</td>
		</tr>
		<tr>
			<td>Permeable membrane system</td>
			<td>Fisher</td>
			<td>7200173</td>
			<td>10-cm dish, 3-mm pore size, polycarbonate membrane</td>
		</tr>
		<tr>
			<td>10 cm dish</td>
			<td>Fisher</td>
			<td>08-772-E</td>
			<td>Tissue culture dish</td>
		</tr>
		<tr>
			<td>15 cm dish</td>
			<td>Fisher</td>
			<td>08-772-24</td>
			<td>Tissue culture dish</td>
		</tr>
		<tr>
			<td>24 well plate</td>
			<td>Fisher</td>
			<td>12565163</td>
			<td>Tissue culture plate</td>
		</tr>
		<tr>
			<td>Lipid-based transfection reagent</td>
			<td>Fisher</td>
			<td>PRE2691</td>
			<td>Can be substituted with other transfection reagent</td>
		</tr>
		<tr>
			<td>Reduced serum media</td>
			<td>Invitrogen</td>
			<td>11058021</td>
			<td>For transfection</td>
		</tr>
		<tr>
			<td>pLL3.7 eGFP</td>
			<td>Addgene</td>
			<td>11795</td>
			<td><a href="https://www.addgene.org/11795/">https://www.addgene.org/11795/</a></td>
		</tr>
		<tr>
			<td>Bottle-top filter</td>
			<td>Fisher</td>
			<td>9761120</td>
			<td>0.45 mm pore</td>
		</tr>
		<tr>
			<td>Polybrene</td>
			<td>Fisher</td>
			<td>NC9840454</td>
			<td>10 mg/mL</td>
		</tr>
		<tr>
			<td>Oleic acid</td>
			<td>Sigma</td>
			<td>01383-5G</td>
			<td>Prevent freeze-thaw cycle</td>
		</tr>
		<tr>
			<td>Lecithin&#160;</td>
			<td>Fisher</td>
			<td>IC10214625</td>
			<td>Egg lecithin&#160;</td>
		</tr>
		<tr>
			<td>Sodium taurocholate</td>
			<td>Fisher</td>
			<td>NC9620276</td>
			<td>Product discontinued; alternative catalog number: 50-121-7956</td>
		</tr>
		<tr>
			<td>Protease inhibitor cocktail tablet (EDTA-free)</td>
			<td>Fisher</td>
			<td>5892791001</td>
			<td>Used mainly for samples that need TEM analysis</td>
		</tr>
		<tr>
			<td>Polycarbonate ultracentrifuge tube</td>
			<td>Fisher</td>
			<td>NC9696153</td>
			<td>Reusing it multiple times will collapse the tube</td>
		</tr>
		<tr>
			<td>Lid for ultracentrifuge tube</td>
			<td>Fisher</td>
			<td>NC9796914</td>
			<td>A tool is required to remove the tube/lid from rotor</td>
		</tr>
		<tr>
			<td>Syringe</td>
			<td>Fisher</td>
			<td>50-949-261</td>
			<td>Disposable</td>
		</tr>
		<tr>
			<td>Syringe filter</td>
			<td>Fisher</td>
			<td>09-719C</td>
			<td>Pore size = 0.2 mm; nylon</td>
		</tr>
		<tr>
			<td>Phosphotungstic acid</td>
			<td>Fisher</td>
			<td>AC208310250</td>
			<td>For preparing 2% phosphotungstic acid, pH 6.0</td>
		</tr>
		<tr>
			<td>Tweezer</td>
			<td>Fisher</td>
			<td>50-238-62</td>
			<td>Extra fine and strong tips</td>
		</tr>
		<tr>
			<td>Formvar/carbon grid</td>
			<td>Fisher</td>
			<td>50-260-34</td>
			<td>Formvar/carbon film square grid 400 Copper</td>
		</tr>
	</tbody>
</table>

using caco-2 cells to study lipid transport by the intestine

Studies of dietary fat absorption are generally conducted by using an animal model equipped with a lymph cannula. Although this animal model is widely accepted as the in vivo model of dietary fat absorption, the surgical techniques involved are challenging and expensive. Genetic manipulation of the animal model is also costly and time consuming. The alternative in vitro model is arguably more affordable, timesaving, and less challenging. Importantly, the in vitro model allows investigators to examine the enterocytes as an isolated system, reducing the complexity inherent in the whole organism model. This paper describes how human colon carcinoma cells (Caco-2) can serve as an in vitro model to study the enterocyte transport of lipids, and lipid-soluble drugs and vitamins. It explains the proper maintenance of Caco-2 cells and the preparation of their lipid mixture; and it further discusses the valuable option of using the permeable membrane system. Since differentiated Caco-2 cells are polarized, the main advantage of using the permeable membrane system is that it separates the apical from the basolateral compartment. Consequently, the lipid mixture can be added to the apical compartment while the lipoproteins can be collected from the basolateral compartment. In addition, the effectiveness of the lentivirus expression system in upregulating gene expression in Caco-2 cells is discussed. Lastly, this paper describes how to confirm the successful isolation of intestinal lipoproteins by transmission electron microscopy (TEM).

図 13日間コンフルエント後のCaco-2細胞1が表示され、正常な。ドーム状構造体の外観および細胞内脂質小滴は、分化したCaco-2細胞の特徴です。のCaco-2細胞を播種時に均等に分散されていないときは、皿の特定の領域に凝集し、過増殖う。任意の細胞を含まない皿の中のいくつかの領域が存在することになります。旋回および傾斜面に皿を置くことは避けるべきです。?...

Watch this Scientific Journal Video about Using Caco-2 Cells to Study Lipid Transport by the Intestine at JoVE.com

Using Caco-2 Cells to Study Lipid Transport by the Intestine

Caco-2 cells can serve as an in vitro model to study the enterocyte transport of lipids, and lipid-soluble drugs/vitamins. The permeable membrane system separates the apical from the basolateral compartment, while the lentivirus expression system offers an effective gene overexpression method. The isolation of lipoproteins is confirmed by TEM.

腸によって脂質輸送を研究するためのCaco-2細胞を用いました

Studies of dietary fat absorption are generally conducted by using an animal model equipped with a lymph cannula. Although this animal model is widely ...

using-caco-2-cells-to-study-lipid-transport-by-the-intestine

Research

JoVE Journal

Biology

18.6K ビュー.  California Northstate University. Caco-2 cells can serve as an in vitro model to study the enterocyte transport of lipids, and lipid-soluble drugs/vitamins. The permeable membrane system separates the apical from the basolateral compartment, while the lentivirus expression system offers an effective gene overexpression method. The isolation of lipoproteins is confirmed by TEM.

ビデオ: Using Caco-2 Cells to Study Lipid Transport by the Intestine

Testing Visual Sensitivity to the Speed and Direction of Motion in Lizards

Testing visual sensitivity in any species provides basic information regarding behaviour, evolution, and ecology. However, testing specific features of the visual system provide more empirical evidence for functional applications. Investigation into the sensory system provides information about the sensory capacity, learning and memory ability, and establishes known baseline behaviour in which to gauge deviations (Burghardt, 1977). However, unlike mammalian or avian systems, testing for learning and memory in a reptile species is difficult. Furthermore, using an operant paradigm as a psychophysical measure of sensory ability is likewise as difficult. Historically, reptilian species have responded poorly to conditioning trials because of issues related to motivation, physiology, metabolism, and basic biological characteristics. Here, I demonstrate an operant paradigm used a novel model lizard species, the Jacky dragon (Amphibolurus muricatus) and describe how to test peripheral sensitivity to salient speed and motion characteristics. This method uses an innovative approach to assessing learning and sensory capacity in lizards. I employ the use of random-dot kinematograms (RDKs) to measure sensitivity to speed, and manipulate the level of signal strength by changing the proportion of dots moving in a coherent direction. RDKs do not represent a biologically meaningful stimulus, engages the visual system, and is a classic psychophysical tool used to measure sensitivity in humans and other animals. Here, RDKs are displayed to lizards using three video playback systems. Lizards are to select the direction (left or right) in which they perceive dots to be moving. Selection of the appropriate direction is reinforced by biologically important prey stimuli, simulated by computer-animated invertebrates.

Testing visual sensitivity in lizards using an operant conditioning paradigm that employs video playback of random-dot kinematograms and computer-generated invertebrates.

トカゲの運動の速度と方向の視覚感度のテスト

Testing visual sensitivity in any species provides basic information regarding behaviour, evolution, and ecology. However, testing specific features of ...

生物学

Computer-Generated Animal Model Stimuli

Communication between animals is diverse and complex. Animals may communicate using auditory, seismic, chemosensory, electrical, or visual signals. In particular, understanding the constraints on visual signal design for communication has been of great interest. Traditional methods for investigating animal interactions have used basic observational techniques, staged encounters, or physical manipulation of morphology. Less intrusive methods have tried to simulate conspecifics using crude playback tools, such as mirrors, still images, or models. As technology has become more advanced, video playback has emerged as another tool in which to examine visual communication (Rosenthal, 2000). However, to move one step further, the application of computer-animation now allows researchers to specifically isolate critical components necessary to elicit social responses from conspecifics, and manipulate these features to control interactions. Here, I provide detail on how to create an animation using the Jacky dragon as a model, but this process may be adaptable for other species. In building the animation, I elected to use Lightwave  3D to alter object morphology, add texture, install bones, and provide comparable weight shading that prevents exaggerated movement. The animation is then matched to select motor patterns to replicate critical movement features. Finally, the sequence must rendered into an individual clip for presentation. Although there are other adaptable techniques, this particular method had been demonstrated to be effective in eliciting both conspicuous and social responses in staged interactions.

Computer-generated stimuli using the Jacky dragon as a model.

コンピュータによって生成された動物モデルの刺激

Communication between animals is diverse and complex. Animals may communicate using auditory, seismic, chemosensory, electrical, or visual signals. In ...

Isolation and Purification of Drosophila Peripheral Neurons by Magnetic Bead Sorting

The Drosophila peripheral nervous system (PNS) is a powerful model for investigating the complex processes of neuronal development and dendrite morphogenesis at the functional and molecular levels. To aid in these analyses, we have developed a strategy for the isolation of a subclass of PNS neurons called dendritic arborization (da) neurons that have been widely used for studying dendrite morphogenesis1,2. These neurons are very difficult to isolate as a pure population, due in part to their extremely low occurrence and their difficult-to-reach location below the tough chitinous larval cuticle. Our newly developed method overcomes these challenges, and is based on a fast and specific cell enrichment using antibody-coated magnetic beads. For our magnetic bead sorting studies, we have used age-matched third instar larvae expressing a mouse CD8 tagged GFP fusion protein (UAS-mCD8-GFP)3 under the control of either the class IV dendritic arborization (da) neuron-specific pickpocket (ppk)-GAL4 driver4 or the control of the pan-da neuron-specific GAL421-7 driver5. Although this protocol has been optimized for isolating PNS cells which are attached to the inner wall of the larval cuticle, by varying a few parameters, the same protocol could be used to isolate many different cell types attached to the cuticle at larval or pupal stages of development (e.g. epithelia, muscle, oenocytes etc.), or other cell types from larval organs depending upon the GAL4-specific driver expression pattern. The RNA isolated by this method is of high quality and can be readily used for downstream genomic analyses such as microarray gene expression profiling studies. This approach offers a powerful new tool to perform studies on isolated Drosophila dendritic arborization (da) neurons thereby providing novel insights into the molecular mechanisms underlying dendrite morphogenesis.

Isolation and Purification of Drosophila Peripheral Neurons by Magnetic Bead Sorting

In this video-article we present a method for the isolation and purification of Drosophila peripheral neurons using a fast magnetic bead assisted cell sorting strategy. RNA obtained from the isolated cells can be readily used for downstream applications including microarray analyses.

の単離と精製ショウジョウバエ</em磁気ビーズソート別>末梢ニューロン

The Drosophila peripheral nervous system (PNS) is a powerful model for investigating the complex processes of neuronal development and dendrite ...

Using the optokinetic response to study visual function of zebrafish

Optokinetic response (OKR) is a behavior that an animal vibrates its eyes to follow a rotating grating around it. It has been widely used to assess the visual functions of larval zebrafish1-5. Nevertheless, the standard protocol for larval fish is not yet readily applicable in adult zabrafish. Here, we introduce how to measure the OKR of adult zebrafish with our simple custom-built apparatus using a new protocol which is established in our lab. Both our apparatus and step-by-step procedure of OKR in adult zebrafish are illustrated in this video. In addition, the measurements of the larval OKR, as well as the optomotor response (OMR) test of adult zebrafish, are also demonstrated in this video. This OKR assay of adult zebrafish in our experiment may last for up to 4 hours. Such OKR test applied in adult fish will benefit to visual function investigation more efficiently when the adult fish vision system is manipulated.
Su-Qi Zou and Wu Yin contributed equally to this paper.

Optokinetic response has been widely used to assess the visual functions of larval zebrafish. Nevertheless, the standard protocol for larval fish is not yet readily applicable in adults1-5. Here, we introduce how to measure the OKR of adult zebrafish using a new protocol which is established in our lab.

ゼブラフィッシュの視覚機能を研究するために視運動性応答を使用して

Optokinetic response (OKR) is a behavior that an animal vibrates its eyes to follow a rotating grating around it. It has been widely used to assess the ...

Measuring Cation Transport by Na,K- and H,K-ATPase in Xenopus Oocytes by Atomic Absorption Spectrophotometry: An Alternative to Radioisotope Assays

Whereas cation transport by the electrogenic membrane transporter Na+,K+-ATPase can be measured by electrophysiology, the electroneutrally operating gastric H+,K+-ATPase is more difficult to investigate. Many transport assays utilize radioisotopes to achieve a sufficient signal-to-noise ratio, however, the necessary security measures impose severe restrictions regarding human exposure or assay design. Furthermore, ion transport across cell membranes is critically influenced by the membrane potential, which is not straightforwardly controlled in cell culture or in proteoliposome preparations. Here, we make use of the outstanding sensitivity of atomic absorption spectrophotometry (AAS) towards trace amounts of chemical elements to measure Rb+ or Li+ transport by Na+,K+- or gastric H+,K+-ATPase in single cells. Using Xenopus oocytes as expression system, we determine the amount of Rb+ (Li+) transported into the cells by measuring samples of single-oocyte homogenates in an AAS device equipped with a transversely heated graphite atomizer (THGA) furnace, which is loaded from an autosampler. Since the background of unspecific Rb+ uptake into control oocytes or during application of ATPase-specific inhibitors is very small, it is possible to implement complex kinetic assay schemes involving a large number of experimental conditions simultaneously, or to compare the transport capacity and kinetics of site-specifically mutated transporters with high precision. Furthermore, since cation uptake is determined on single cells, the flux experiments can be carried out in combination with two-electrode voltage-clamping (TEVC) to achieve accurate control of the membrane potential and current. This allowed e.g. to quantitatively determine the 3Na+/2K+ transport stoichiometry of the Na+,K+-ATPase and enabled for the first time to investigate the voltage dependence of cation transport by the electroneutrally operating gastric H+,K+-ATPase. In principle, the assay is not limited to K+-transporting membrane proteins, but it may work equally well to address the activity of heavy or transition metal transporters, or uptake of chemical elements by endocytotic processes.

Measuring Cation Transport by Na,K- and H,K-ATPase in Xenopus Oocytes by Atomic Absorption Spectrophotometry: An Alternative to Radioisotope Assays

We describe a method to quantify the activity of K+-countertransporting P-type ATPases by heterologous expression of the enzymes in Xenopus oocytes and measuring Rb+ or Li+ uptake into individual cells by atomic absorption spectrophotometry. The method is a sensitive and safe alternative to radioisotope flux experiments facilitating complex kinetic studies.

のNa、KとH、K-ATPaseのインによって陽イオン輸送を測定する<em&gt;アフリカツメガエル</em原子吸光法による&gt;卵母：アイソトープアッセイの代替

Whereas cation transport by the electrogenic membrane transporter Na+,K+-ATPase can be measured by electrophysiology, the electroneutrally operating ...

Methods to Study Epithelial Transport Protein Function and Expression in Native Intestine and Caco-2 Cells Grown in 3D

The intestinal epithelium has important transport and barrier functions that play key roles in normal physiological functions of the body while providing a barrier to foreign particles. Impaired epithelial transport (ion, nutrient, or drugs) has been associated with many diseases and can have consequences that extend beyond the normal physiological functions of the transporters, such as by influencing epithelial integrity and the gut microbiome. Understanding the function and regulation of transport proteins is critical for the development of improved therapeutic interventions. The biggest challenge in the study of epithelial transport is developing a suitable model system that recapitulates important features of the native intestinal epithelial cells. Several in vitro cell culture models, such as Caco-2, T-84, and HT-29-Cl.19A cells are typically used in epithelial transport research. These cell lines represent a reductionist approach to modeling the epithelium and have been used in many mechanistic studies, including their examination of epithelial-microbial interactions. However, cell monolayers do not accurately reflect cell-cell interactions and the in vivo microenvironment. Cells grown in 3D have shown to be promising models for drug permeability studies. We show that Caco-2 cells in 3D can be used to study epithelial transporters. It is also important that studies in Caco-2 cells are complemented with other models to rule out cell specific effects and to take into account the complexity of the native intestine. Several methods have been previously used to assess the functionality of transporters, such as everted sac and uptake in isolated epithelial cells or in isolated plasma membrane vesicles. Taking into consideration the challenges in the field with respect to models and the measurement of transport function, we demonstrate here a protocol to grow Caco-2 cells in 3D and describe the use of an Ussing chamber as an effective approach to measure serotonin transport, such as in intact polarized intestinal epithelia.

We describe simple methods to study the regulation of intestinal serotonin transporter (SERT) function and expression using an in vitro cell culture model of Caco-2 cells grown in 3D&#160;and an ex vivo model of mouse intestines. These methods are applicable to the study of other epithelial transporters.

3Dで栽培ネイティブ腸とのCaco-2細胞において上皮輸送タンパク質の機能および発現を研究するための方法

The intestinal epithelium has important transport and barrier functions that play key roles in normal physiological functions of the body while providing ...

Mixed Primary Cultures of Murine Small Intestine Intended for the Study of Gut Hormone Secretion and Live Cell Imaging of Enteroendocrine Cells

The gut is the largest endocrine organ of the body, with hormone-secreting enteroendocrine cells located along the length of the gastrointestinal epithelium. Despite their physiological importance, enteroendocrine cells represent only a small fraction of the epithelial cell population and in the past, their characterization has presented a considerable challenge resulting in a reliance on cell line models. Here, we provide a detailed protocol for the isolation and culture of mixed murine small intestinal cells. These primary cultures have been used to identify the signaling pathways underlying the stimulation and inhibition of gut peptide secretion in response to a number of nutrients and neuropeptides as well as pharmacological agents. Furthermore, in combination with the use of transgenic fluorescent reporter mice, we have demonstrated that these primary cultures become a powerful tool for the examination of fluorescently-tagged enteroendocrine cells at the intracellular level, using methods such as patch clamping and single-cell calcium and cAMP-FRET imaging.

This protocol describes the isolation and culture of mixed murine small intestinal cells. These primary intestinal cultures enable the investigation of signaling pathways underlying gut peptide secretion using a number of techniques.

腸ホルモン分泌の研究と腸内分泌細胞の生細胞イメージングを対象ネズミ小腸の混合初代培養

The gut is the largest endocrine organ of the body, with hormone-secreting enteroendocrine cells located along the length of the gastrointestinal ...

Tethered Bilayer Lipid Membranes to Monitor Heat Transfer between Gold Nanoparticles and Lipid Membranes

Here we report a protocol to investigate the heat transfer between irradiated gold nanoparticles (GNPs) and bilayer lipid membranes by electrochemistry using tethered bilayer lipid membranes (tBLMs) assembled on gold electrodes. Irradiated modified GNPs, such as streptavidin-conjugated GNPs, are embedded in tBLMs containing target molecules, such as biotin. By using this approach, the heat transfer processes between irradiated GNPs and model bilayer lipid membrane with entities of interest are mediated by a horizontally focused laser beam. The thermal predictive computational model is used to confirm the electrochemically induced conductance changes in the tBLMs. Under the specific conditions used, detecting heat pulses required specific attachment of the gold nanoparticles to the membrane surface, while unbound gold nanoparticles failed to elicit a measurable response. This technique serves as a powerful detection biosensor which can be directly utilized for the design and development of strategies for thermal therapies that permits optimization of the laser parameters, particle size, particle coatings and composition.

This work outlines a protocol to achieve dynamic, non-invasive monitoring of heat transfer from laser-irradiated gold nanoparticles to tBLMs. The system combines impedance spectroscopy for the real-time measurement of conductance changes across the tBLMs, with a horizontally focused laser beam that drives gold nanoparticle illumination, for heat production.

金ナノ粒子と脂質膜の熱伝達をモニターする二重層脂質膜

Here we report a protocol to investigate the heat transfer between irradiated gold nanoparticles (GNPs) and bilayer lipid membranes by electrochemistry ...

Isolation of Mouse Interstitial Valve Cells to Study the Calcification of the Aortic Valve In Vitro

The calcification of aortic valve cells is the hallmark of aortic stenosis and is associated with valve cusp fibrosis. Valve interstitial cells (VICs) play an important role in the calcification process in aortic stenosis through the activation of their dedifferentiation program to osteoblast-like cells. Mouse VICs are a good in vitro tool for the elucidation of the signaling pathways driving the mineralization of the aortic valve cell. The method described herein, successfully used by these authors, explains how to obtain freshly isolated cells. A two-step collagenase procedure was performed with 1 mg/mL and 4.5 mg/mL. The first step is crucial to remove the endothelial cell layer and avoid any contamination. The second collagenase incubation is to facilitate the migration of VICs from the tissue to the plate. In addition, an immunofluorescence staining procedure for the phenotype characterization of the isolated mouse valve cells is discussed. Furthermore, the calcification assay was performed in vitro by using the calcium reagent measurement procedure and alizarin red staining. The use of mouse valve cell primary culture is essential for testing new pharmacological targets to inhibit cell mineralization in vitro.

Isolation of Mouse Interstitial Valve Cells to Study the Calcification of the Aortic Valve In Vitro

This article describes the isolation of mouse aortic valve cells by a two-step collagenase procedure. Isolated mouse valve cells are important for performing different assays, such as this in vitro calcification assay, and for investigating the molecular pathways leading to aortic valve mineralization.

マウス間質弁細胞の分離を用いて大動脈弁の石灰化を 研究

The calcification of aortic valve cells is the hallmark of aortic stenosis and is associated with valve cusp fibrosis. Valve interstitial cells (VICs) ...

The Caco-2 Cell Bioassay for Measurement of Food Iron Bioavailability

Knowledge of Fe bioavailability is critical to the assessment of the nutritional quality of Fe in foods. In vivo measurement of Fe bioavailability is limited by cost, throughput, and the caveats inherent to isotopic labeling of the food Fe. Thus, there exists a critical need for an approach that is high-throughput and cost-effective. The Caco-2 cell bioassay was developed to satisfy this need. The Caco-2 cell bioassay for Fe bioavailability utilizes simulated gastric and intestinal digestion coupled with culture of a human intestinal epithelial cell line known as Caco-2. In Caco-2 cells, Fe uptake stimulates the intracellular formation of ferritin, an Fe storage protein easily measured by enzyme-linked immunosorbent assay (ELISA). Ferritin forms in proportion to Fe uptake; thus, by measuring Caco-2 cell ferritin production, one can assess intestinal Fe uptake from simulated food digests into the enterocyte. 
Via this approach, the model replicates the key initial step that determines food Fe bioavailability. Since its inception in 1998, this model approach has been rigorously compared to factors known to influence human Fe bioavailability. Moreover, it has been applied in parallel studies, with three human efficacy studies evaluating Fe biofortified crops. In all cases, the bioassay correctly predicted the relative amounts of Fe bioavailability from the factors, crops, and overall diet. This paper provides detailed methods on Caco-2 cell culture coupled with the in vitro digestion process and cell ferritin ELISA necessary to conduct the Caco-2 cell bioassay for Fe bioavailability.

The Caco-2 cell bioassay for iron (Fe) bioavailability represents a cost-effective and versatile approach to assess Fe bioavailability from foods, food products, supplements, meals, and even diet regimens. Thoroughly validated to human studies, it represents the state of the art for studies of Fe bioavailability.

食品鉄バイオアベイラビリティ測定のためのCaco-2細胞バイオアッセイ

Knowledge of Fe bioavailability is critical to the assessment of the nutritional quality of Fe in foods. In vivo measurement of Fe bioavailability is ...