この作品は、アメリカ心臓協会GRAの春09ポストドクトラルフェローシップ（09POST2250268）およびNIH R01 CA097465によって部分的にサポートされています。我々は非常に腫瘍移植の彼女の援助のために博士ウェン李博士とヴィカスGulaniのMRIプロトコル·テストとセットアップのため、氏とイヴォンヌ·パーカーを高く評価しています。

プロトコルは、以前の研究11から適応。 1。 CLT1ペプチドにのGd-DOTAの結合体<ol><li>標準固相ペプチド合成を使用して、2 - クロロトリチルクロリド樹脂上のFmoc-保護アミノ酸（1.0ミリモル）からCLT1ペプチド（CGLIIQKNEC）を合成する。 </li><li>最後のアミノ酸を添加した後、2時間0℃でDMF中のタリウム（III）トリフルオロ酢酸塩（1​​.09g、2.0ミリモル、2当量）を用いて樹脂上の線状ペプチド（20ml）に環化する。 </li><li>次に、コンジュゲートPEGおよびFmoc-NH-PEG-COOH（3.0ミリモル）のFmoc-Lysのカルボニル（Fmoc）-OH（3.0ミリモル）で連続的に反応させることにより、樹脂上CLT1ペプチド（1.0ミリモル）のN末端へのリジンを順次、およびFmoc-Lysのカルボニル（Fmoc）-OH（6）の第二バッチ。 </li><li>ピペリジンでのFmocを除去します。 2時間、樹脂上のリシンデンドリマーから4本の遊離アミンと反応するDOTA-トリス（Buはt-ブチル）（4.58g、8.0ミリモル、各アミノ基に2当量）を添加する。 </li><li>最後に、生成物を切断し、脱保護樹脂からの室温で8時間、トリフルオロ酢酸、水、およびトリイソブチル（TIS）（20ミリリットル、95/2.5/2.5）のカクテルで処理することによって。トリフルオロ酢酸（TFA）で洗浄した濾過により樹脂を除去。合わせたろ液は、遠心分離器、冷たいエチルエーテル（200ミリリットル）に滴下追加し、エチルエーテル4Xで洗浄する。無色の固体（1.99g、61％収率）を得、真空下で乾燥させる。 </li><li> 10分間の溶媒Aで20分間、40〜90％溶媒Bのための溶媒A（0.1％TFA水溶液）中アセトニトリル（0.1％TFA）〜40％溶媒Bの勾配を使用する分取HPLCで粗生成物を精製し。 </li><li>溶解DI水中CLT1-DL-（DOTA）4（250mgを、0.077ミリモル）（15ml）および1 M NaOHを用いてpHを6に調整する。 1 M NaOHを用いてpHを6に維持しながら、溶液に少しずつのGd（OAcでの）3·H 2 O（472ミリグラム、0.462ミリモル、DOTAモノアミドに1.5当量）を添加する。 48時間RTで反応液を撹拌した。 </li><li> Eとの複合体の残存のGd（III）thylenediaminetetraacetic酢酸（EDTA）（90mg、0.31ミリモル）、及び最終製品CLT1-DL-（のGd-DOTA）4（169mg、57％）を得サイズ排除カラムで粗生成物を精製する。 </li></ol> 2。造影剤の特性評価<ol><li>誘導結合プラズマ発光分光分析とのGd（III）の含有量を測定する。 </li><li>マトリックスとして2,5 - ジヒドロキシ安息香酸（2,5-DHB）を用いて線形モードで、マトリックス支援レーザー脱離/イオン化飛行時間型（MALDI-TOF）質量スペクトルを取得する。 </li><li>緩和計with CLT1-デシリットル-（のGd DOTA）4コントラスト剤および非標的制御エージェント60メガヘルツ（1.5 T）少なくとも異なる濃度sCLT1-デシリットル-（のGd DOTA）4水溶液緩和時間を測定37℃で、 T 2を測定するために、500のエコーとT 1とハーンメイブーム-ギルシーケンスを測定するために、反転回復パルスシーケンスを使用しています。 T 1とTを目の2緩和を計算するGdの濃度対1 / T 1および1 / T 2のプロットの傾きから電子剤。 </li></ol> 3。同所PC3前立腺腫瘍を持つ動物モデルの細胞培養および開発<ol><li> /μlのPBS 2.5×10 4細胞の密度で、5％ウシ胎児血清およびペニシリン/ストレプトマイシン/ファンギゾン、トリプシン処理によって収穫し、再懸濁を補充したRPMI培地中で緑色蛍光タンパク質（GFP）の構成的発現を有する培養PC3前立腺癌細胞。 </li><li> CWRU機関動物実験委員会によって承認された動物プロトコルに従って胸腺欠損動物基盤施設の雄のNIH胸腺ヌードマウス（4-5週齢）、ケースウエスタンリザーブ大学（CWRU）を維持する。 </li><li>外科用表面は、2％クロルヘキシジン溶液を噴霧し、次いで、吸収性ドレープで覆った。無菌手術用手袋は、手術中に着用された。動物の手術前に、IPはanesthetizにアベルチン（250 mg / kgの）を注入マウスを電子。代替的に、ケタミン/キシラジン/アセプロマジンで50/5/1 mg / kgの濃度で使用することができる。眼軟膏は、麻酔中に十分な水分を維持するために、マウスに適用した。 </li><li>滅菌メスを使用して約1cmの長さで下正中線に沿って皮膚や腹膜を通して小さな切開を切断することにより、手術を開始します。無菌手術用ドレープは、生存の手術の際に切開部位を中心に覆われていた。 </li><li>優しく前立腺を露出させ、前立腺背側葉を体外にして安定させる。 30ゲージの針を用いて前立腺にPBS（20μL）で、PC3-GFP細胞の懸濁液を注入する。最終的に創傷オートクリップ12で切開を閉じます。 </li><li>後手順の監視については、1週間1日2回、動物を監視します。病気の兆候は食べるの欠如、尿道の周りの濃い尿の収集、およびステープルで膀胱の感染症や閉塞を示している可能性が不安定歩行が含まれています。 </li><li> 10日後、Tを削除彼は、ステープルステープルリムーバーを使用して。腫瘍サイズおよび体重減少、行動偏差、モータ欠陥などの疼痛の証拠を評価するために動物を毎日監視する。腫瘍増殖の際の痛みの倫理的に許容限度又は証拠を超える腫瘍サイズを示した動物を安楽死させる。 </li></ol> 4。蛍光イメージングおよび組織学を有するペプチドの結合特異性腫瘍の確認<ol><li>腫瘍細胞接種の後、腫瘍増殖の約4週間撮像始まる前に可能にする。ペプチドプローブの注射の前に、腫瘍の存在を確認するために、蛍光イメージャー上の生きたマウスでGFP蛍光画像を取得する。 </li><li> IVは、テキサスレッドが10ナノモル/マウスの用量で腫瘍を有するマウスにペプチドをラベル注入する。 </li><li>頸椎脱臼により2時間後にマウスを犠牲に、腫瘍および主要な器官を収集し、すぐに蛍光イメージャー上の画像。 44：GFP（励起用の緑色光フィルタを使用する4から490ナノメートル、放出：515 nmのロングパスフィルタ、取得設定：テキサスレッドための10 nmのステップで500から720）と赤色光フィルター（励起：576から621ナノメートル;放射：635nmのロングパスフィルタ;買収設定：10 nmのステップで630から800）。 GFP及びテキサスレッド、150ミリ秒10ミリ秒の露光時間。 </li><li>すぐに全体の組織蛍光を測定した後、腫瘍組織を収集し、ホルマリンで固定し、凍結切片5μmのスライスに。 </li><li> PBSですすいだ後、直ちに、共焦点レーザー走査顕微鏡に4 &#39;、6 - ジアミジノ-2 - フェニルインドール（DAPI）を含有する封入剤1滴、画像にマウントする。 </li></ol> 5。磁気共鳴イメージング（MRI） <ol><li>腫瘍細胞接種後約4週間は、腫瘍の直径が0.3〜0.6センチメートルまで成長することができます。 MRIの研究のためのボリュームの無線周波数（RF）コイルが7 T MRIスキャナを使用してください。 </li><li>イソフルラン誘導チャンバ内の2％イソフルランと酸素の混合物で、マウスを麻酔。 OPHthalmic軟膏は、麻酔中に十分な水分を維持するために、マウスに適用した。 </li><li>ヘパリン処理した生理食塩水で満たされた1.0メートルの長いチューブに30ゲージの針を挿入します。マウス尾静脈に自作のカテーテルを配置します。 </li><li>磁石にマウスを置き、ノーズ​​コーンを経由して1.5％イソフルランと酸素と吸入麻酔下に保つ。 </li><li>呼吸の速度と深さを監視するための腹部に監視システムに接続され、呼吸センサーを配置します。フィードバック制御システムを介して磁石に熱風を吹き込んで、37℃で体温を維持する。 </li><li>腫瘍の位置（TR / TE = 200/3.7ミリ秒、FOV = 3.0センチメートル、スライス厚= 2.2ミリメートル、2 =平均スライス数= 16、フリップ角度= 45°を識別するために局在化配列を用いてサジタル断面画像で始まるマトリックス= 128×128）。 </li><li> CE-MRI（TR / TE = 151.2/1.9ミリ秒、FOV = 3.0センチ×3.0センチメートル、用2Dアキシャル画像を取得するために2次元T1強調勾配脂肪抑制シーケンスを使用して、Sシラミ厚さ= 1.2ミリメートル、スライス番号= 12、平均= 1、フリップ角= 80°、マトリックス= 128×128）。 </li><li>注入前のベースラインMR画像の取得後に、生理食塩水200μlでフラッシュすることにより0.03ミリモルのGd / kgの用量で標的化剤または抑制剤を注入し始める。 </li><li>最大30分間、異なる時点でCE-MRI画像を取得し続ける。 </li></ol> 6。画像処理と解析<ol><li>画像解析のためのイメージングソフトウェアを使用してください。 </li><li> 2次元の撮像面に全腫瘍の上の関心領域（ROI）と腎臓を引き出し、平均信号強度を測定する。 </li><li> （S 0 - ΔSNR=（S トン/σt）は ：CE-MRIデータを定量化するために、以下の式を用いて造影前SNRオーバー造影後SNRの増加を計算することによって、腫瘍または腎臓コントラスト強調（ΔSNR）を測定/σ0）、S 0、SはTタムの信号を表す場合、またはまたはコントラスト前と後の腎臓、σ0、σtは 、コントラストの前後背景空気から測定されたノイズの標準偏差である。 </li><li> 、p &lt;0.05で統計的有意性を仮定し、スチューデントの両側t検定を用いてp値を計算する。 </li></ol>

<ol>
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重要なステップ 適切なバイオマーカーの選択と小ペプチドをターゲットに 正常に小さいサイズを有する標的化造影剤を開発するために、2つの重要な点を考慮する必要がある。第一に、正常組織にはほとんど存在感のある病変組織に豊富に存在する適切な分子バイオマーカーを選択することが重要である。私たちの選択された癌関連バイオ...

癌に関連する分子標的の有効撮像は、以前の癌の検出および診断の精度を向上させるために非常に重要である。磁気共鳴イメージング（MRI）は、高空間分解能なし電離放射線1を備えた強力な臨床イメージング様式である。ただし、対象となる造影剤は、臨床MRがん分子イメージングのため利用できません。目標とMRI造影剤の革新的なデザインと開発は大幅にMRがん分子イメージングの応用を進めるだろう。かなりの努力が、癌細胞の表面に発現されるバイオマーカーのMRイメージングのための標的造影剤の開発がなされてきた。によるMRI及びこれらのバイオマーカーの低濃度の比較的低い感度のために、小さな分子標的造影剤2,3を用いた効果的なMR分子イメージングのための十分なコントラスト強調を生成することが課題である。十分な増強を得るために、種々の送達系の成功常磁性のGd（III）キレートの高いペイロードを有するリポソーム、ナノ粒子及びポリマー結合体としてのhは、標的部位での4,5造影剤の局所濃度を増加させるために調製されている。これらの送達システムは、動物モデルにおいて有意な腫瘍増強を生成することができたが、それらの大きなサイズは、重大な安全上の懸念6原因となり、毒性のGd（III）イオンの長期蓄積をもたらす、身体からゆっくりと不完全な除去をもたらした。最近、いくつかの研究は、分子イメージングのためのMRIの限界が高い局所病変において発現と適切な分子バイオマーカーを選択し、容易に7,8排泄することができる小分子薬剤を使用することによって克服することができることを示している。これらの薬剤の重要な特徴は、正常組織にはほとんど存在感のある病変組織に豊富に存在する分子マーカーを標的としていることである。造影剤の高い濃度が十分に得られ、これらの標的に結合することができる効果的なMR分子イメージングのための効率の良いコントラスト強調。それらのサイズは腎臓濾過閾値よりも小さいので、結合していない造影剤は、容易に縮小背景ノイズが体内から排出することができる。私たちは、豊富に腫瘍間質に存在する凝固血漿タンパク質を、普遍的な癌関連バイオマーカーを選択し、まれに正常組織9に存在していない。我々は、強力なPC3前立腺腫瘍モデル10への特異的結合、および4つのGd-DOTAモノアミドキレートを示し、小さな標的化ペプチドCGLIIQKNEC（CLT1）を含む標的化造影剤を合成した。ここでは、マウスにおいて腫瘍を検出するためのMR癌分子イメージングのための方法を提供する。

<table border="1">
		<tbody>
		 <tr>
			<td></td>
			<td></td>
			<td></td>
			<td>REAGENTS</td>
		 </tr>
		 <tr>
			<td>Fmoc protected amino acids</td>
			<td>EMD Chemicals Inc</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>DOTA-tris(t-Bu)</td>
			<td>TCI America</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>PyBOP, HOBt, HBTU</td>
			<td>Nova Biochem</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>DIPEA, Thallium(III) trifluoroacetate, TIS</td>
			<td>Sigma-Aldrich Corp.</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Texas Red, succinimidyl ester, single isomer</td>
			<td>Invitrogen</td>
			<td>T20175</td>
			<td></td>
		 </tr>
		 <tr>
			<td></td>
			<td></td>
			<td></td>
			<td>EQUIPMENTS</td>
		 </tr>
		 <tr>
			<td>Agilent 1100 HPLC system</td>
			<td>Agilent</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>ZORBAX 300SB-C18 PrepHT column</td>
			<td>Agilent</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>ICP-OES Optima 3100XL</td>
			<td>Perkin-Elmer</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>MALDI-TOF mass spectrometer</td>
			<td>Bruker</td>
			<td>AutoflexTM Speed</td>
			<td></td>
		 </tr>
		 <tr>
			<td>Maestro FLEX In Vivo Imaging System</td>
			<td>Cambridge Research &amp; Instrumentation, Inc.</td>
			<td></td>
			<td></td>
		 </tr>
		 <tr>
			<td>Biospec 7T MRI scanner</td>
			<td>Bruker</td>
			<td></td>
			<td></td>
		 </tr>
		</tbody>
 </table>

mr molecular imaging of prostate cancer with a small molecular clt1 peptide targeted contrast agent

腫瘍細胞外マトリックス分子イメージングは​​、癌のバイオマーカーとして使用することができる癌関連タンパク質の存在量を有する。本研究では、腫瘍間質内凝固した血漿タンパク質に特有の標的MRI造影剤としてのGd-DOTAモノアミド複合体の標的小分子のペプチドを用いた効果的なのMRがん分子イメージングを示した。我々は、マウス同所性PC-3前立腺癌モデルにおけるMRIによる前立腺腫瘍の非侵襲的検出のための薬剤の有効性を評価する実験を行った。標的化造影剤は、0.03ミリモルのGd / kgの低用量で有意な腫瘍コントラスト強調を生成するのに有効であった。ペプチド標的化MRI造影剤は、前立腺腫瘍のMR分子イメージングのために有望である。

図1は、標的化造影剤CLT1-DL-（のGd-DOTA）4、実験の全体的なスキームの合成を示す。 CLT1-DL-（GD-DOTA）4臨床のGd-DOTA（表1）よりもはるかに高い緩和度を示しています。 1.5 Tで、PBS（pH7.4）中CLT1-DL-（のGd-DOTA）4のガドリニウム当たりのT 1緩和度のGd-DOTA 10のそれよりも約3倍高い。マエストロイメージングは、非特異的ペプチド（sCLT1-TR）をスク?...

Watch this Scientific Journal Video about MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent at JoVE.com

MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

マウス前立腺癌モデルにおける腫瘍間質内の凝固した血漿タンパク質に特異的な小ペプチド標的化MRI造影剤を用いてMR癌の分子イメージングを実証した。

低分子CLT1ペプチド標的造影剤を用いて前立腺がんの分子イメージングのMR

Tumor extracellular  matrix has abundance of cancer related proteins that can be used as biomarkers  for cancer molecular imaging. In this work,  we ...

mr-molecular-imaging-prostate-cancer-with-small-molecular-clt1

Research

JoVE Journal

Medicine

11.1K ビュー.  Case Western Reserve University. マウス前立腺癌モデルにおける腫瘍間質内の凝固した血漿タンパク質に特異的な小ペプチド標的化MRI造影剤を用いてMR癌の分子イメージングを実証した。 

ビデオ: MR Molecular Imaging of Prostate Cancer with a Small Molecular CLT1 Peptide Targeted Contrast Agent

In vivo Near Infrared Fluorescence (NIRF) Intravascular Molecular Imaging of Inflammatory Plaque, a Multimodal Approach to Imaging of Atherosclerosis

The vascular response to injury is a well-orchestrated inflammatory response triggered by the accumulation of macrophages within the vessel wall leading to an accumulation of lipid-laden intra-luminal plaque, smooth muscle cell proliferation and progressive narrowing of the vessel lumen. The formation of such vulnerable plaques prone to rupture underlies the majority of cases of acute myocardial infarction. The complex molecular and cellular inflammatory cascade is orchestrated by the recruitment of T lymphocytes and macrophages and their paracrine effects on endothelial and smooth muscle cells.1
Molecular imaging in atherosclerosis has evolved into an important clinical and research tool that allows in vivo visualization of inflammation and other biological processes. Several recent examples demonstrate the ability to detect high-risk plaques in patients, and assess the effects of pharmacotherapeutics in atherosclerosis.4 While a number of molecular imaging approaches (in particular MRI and PET) can image biological aspects of large vessels such as the carotid arteries, scant options exist for imaging of coronary arteries.2 The advent of high-resolution optical imaging strategies, in particular near-infrared fluorescence (NIRF), coupled with activatable fluorescent probes, have enhanced sensitivity and led to the development of new intravascular strategies to improve biological imaging of human coronary atherosclerosis.
Near infrared fluorescence (NIRF) molecular imaging utilizes excitation light with a defined band width (650-900 nm) as a source of photons that, when delivered to an optical contrast agent or fluorescent probe, emits fluorescence in the NIR window that can be detected using an appropriate emission filter and a high sensitivity charge-coupled camera. As opposed to visible light, NIR light penetrates deeply into tissue, is markedly less attenuated by endogenous photon absorbers such as hemoglobin, lipid and water, and enables high target-to-background ratios due to reduced autofluorescence in the NIR window. Imaging within the NIR 'window' can substantially improve the potential for in vivo imaging.2,5
Inflammatory cysteine proteases have been well studied using activatable NIRF probes10, and play important roles in atherogenesis. Via degradation of the extracellular matrix, cysteine proteases contribute importantly to the progression and complications of atherosclerosis8. In particular, the cysteine protease, cathepsin B, is highly expressed and colocalizes with macrophages in experimental murine, rabbit, and human atheromata.3,6,7 In addition, cathepsin B activity in plaques can be sensed in vivo utilizing a previously described 1-D intravascular near-infrared fluorescence technology6, in conjunction with an injectable nanosensor agent that consists of a poly-lysine polymer backbone derivatized with multiple NIR fluorochromes (VM110/Prosense750, ex/em 750/780nm, VisEn Medical, Woburn, MA) that results in strong intramolecular quenching at baseline.10 Following targeted enzymatic cleavage by cysteine proteases such as cathepsin B (known to colocalize with plaque macrophages), the fluorochromes separate, resulting in substantial amplification of the NIRF signal. Intravascular detection of NIR fluorescence signal by the utilized novel 2D intravascular NIRF catheter now enables high-resolution, geometrically accurate in vivo detection of cathepsin B activity in inflamed plaque.
In vivo molecular imaging of atherosclerosis using catheter-based 2D NIRF imaging, as opposed to a prior 1-D spectroscopic approach,6 is a novel and promising tool that utilizes augmented protease activity in macrophage-rich plaque to detect vascular inflammation.11,12 The following research protocol describes the use of an intravascular 2-dimensional NIRF catheter to image and characterize plaque structure utilizing key aspects of plaque biology. It is a translatable platform that when integrated with existing clinical imaging technologies including angiography and intravascular ultrasound (IVUS), offers a unique and novel integrated multimodal molecular imaging technique that distinguishes inflammatory atheromata, and allows detection of intravascular NIRF signals in human-sized coronary arteries.

In vivo Near Infrared Fluorescence NIRF Intravascular Molecular Imaging of Inflammatory Plaque, a Multimodal Approach to Imaging of Atherosclerosis

We detail a new near-infrared fluorescence (NIRF) catheter for 2-dimensional intravascular molecular imaging of plaque biology in vivo. The NIRF catheter can visualize key biological processes such as inflammation by reporting on the presence of plaque-avid activatable and targeted NIR fluorochromes. The catheter utilizes clinical engineering and power requirements and is targeted for application in human coronary arteries. The following research study describes a multimodal imaging strategy that utilizes a novel in vivo intravascular NIRF catheter to image and quantify inflammatory plaque in proteolytically active inflamed rabbit atheromata.

炎症性プラークの赤外蛍光（NIRF）血管内分子イメージング、マルチモーダルアプローチの近くin vivoでの動脈硬化のイメージングに

The vascular response to injury is a well-orchestrated inflammatory response triggered by the accumulation of macrophages within the vessel wall leading ...

医学

Contrast Enhanced Vessel Imaging using MicroCT

Microscopic computed tomography (microCT) offers high-resolution volumetric imaging of the anatomy of living small animals. However, the contrast between different soft tissues and body fluids is inherently poor in micro-CT images 1. Under these circumstances, visualization of blood vessels becomes a nearly impossible task. To overcome this and to improve the visualization of blood vessels exogenous contrast agents can be used. Herein, we present a methodology for visualizing the vascular network in a rodent model. By using a long-acting aqueous colloidal polydisperse iodinated blood-pool contrast agent, eXIA 160XL, we optimized image acquisition parameters and volume-rendering techniques for finding blood vessels in live animals. Our findings suggest that, to achieve a superior contrast between bone and soft tissue from vessel, multiple-frames (at least 5-8/ frames per view), and 360-720 views (for a full 360&deg; rotation) acquisitions were mandatory. We have also demonstrated the use of a two-dimensional transfer function (where voxel color and opacity was assigned in proportion to CT value and gradient magnitude), in visualizing the anatomy and highlighting the structure of interest, the blood vessel network. This promising work lays a foundation for the qualitative and quantitative assessment of anti-angiogenesis preclinical studies using transgenic or xenograft tumor-bearing mice.

Contrast enhanced small animal vessel imaging by microCT is a rapid, cost-effective and high-throughput technique for serial in situ examination for tumor development, for analyzing the network of blood vessels that nourish them, and for following the response of tumors to preclinical therapeutic intervention(s).

MicroCTを使用して造影血管イメージング

Microscopic computed tomography (microCT) offers high-resolution volumetric imaging of the anatomy of living small animals. However, the contrast between ...

Evaluation of Nanoparticle Uptake in Tumors in Real Time Using Intravital Imaging

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle uptake in tumors at the microscopic level1,2,3, highlighting the utility of a suitable xenograft model in which to perform detailed uptake analyses. Here, we use high-resolution intravital imaging to evaluate nanoparticle uptake in human tumor xenografts in a modified, shell-less chicken embryo model. The chicken embryo model is particularly well-suited for these in vivo analyses because it supports the growth of human tumors, is relatively inexpensive and does not require anesthetization or surgery 4,5. Tumor cells form fully vascularized xenografts within 7 days when implanted into the chorioallantoic membrane (CAM) 6. The resulting tumors are visualized by non-invasive real-time, high-resolution imaging that can be maintained for up to 72 hours with little impact on either the host or tumor systems. Nanoparticles with a wide range of sizes and formulations administered distal to the tumor can be visualized and quantified as they flow through the bloodstream, extravasate from leaky tumor vasculature, and accumulate at the tumor site. We describe here the analysis of nanoparticles derived from Cowpea mosaic virus (CPMV) decorated with near-infrared fluorescent dyes and/or polyethylene glycol polymers (PEG) 7, 8, 9,10,11. Upon intravenous administration, these viral nanoparticles are rapidly internalized by endothelial cells, resulting in global labeling of the vasculature both outside and within the tumor7,12. PEGylation of the viral nanoparticles increases their plasma half-life, extends their time in the circulation, and ultimately enhances their accumulation in tumors via the enhanced permeability and retention (EPR) effect 7, 10,11. The rate and extent of accumulation of nanoparticles in a tumor is measured over time using image analysis software. This technique provides a method to both visualize and quantify nanoparticle dynamics in human tumors.

We present a novel approach to quantify nanoparticle localization in the vasculature of human xenografted tumors using dynamic, real-time intravital imaging in an avian embryo model.

生体内イメージングを使ってリアルタイムで腫瘍におけるナノ粒子の取り込みの評価

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle ...

Molecular Imaging to Target Transplanted Muscle Progenitor Cells

Duchenne muscular dystrophy (DMD) is a severe genetic neuromuscular disorder that affects 1 in 3,500 boys, and is characterized by progressive muscle degeneration1, 2. In patients, the ability of resident muscle satellite cells (SCs) to regenerate damaged myofibers becomes increasingly inefficient4. Therefore, transplantation of muscle progenitor cells (MPCs)/myoblasts from healthy subjects is a promising therapeutic approach to DMD. A major limitation to the use of stem cell therapy, however, is a lack of reliable imaging technologies for long-term monitoring of implanted cells, and for evaluating its effectiveness. Here, we describe a non-invasive, real-time approach to evaluate the success of myoblast transplantation. This method takes advantage of a unified fusion reporter gene composed of genes (firefly luciferase [fluc], monomeric red fluorescent protein [mrfp] and sr39 thymidine kinase [sr39tk]) whose expression can be imaged with different imaging modalities9, 10. A variety of imaging modalities, including positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), optical imaging, and high frequency 3D-ultrasound are now available, each with unique advantages and limitations11. Bioluminescence imaging (BLI) studies, for example, have the advantage of being relatively low cost and high-throughput. It is for this reason that, in this study, we make use of the firefly luciferase (fluc) reporter gene sequence contained within the fusion gene and bioluminescence imaging (BLI) for the short-term localization of viable C2C12 myoblasts following implantation into a mouse model of DMD (muscular dystrophy on the X chromosome [mdx] mouse)12-14. Importantly, BLI provides us with a means to examine the kinetics of labeled MPCs post-implantation, and will be useful to track cells repeatedly over time and following migration. Our reporter gene approach further allows us to merge multiple imaging modalities in a single living subject; given the tomographic nature, fine spatial resolution and ability to scale up to larger animals and humans10,11, PET will form the basis of future work that we suggest may facilitate rapid translation of methods developed in cells to preclinical models and to clinical applications.

A non-invasive means to evaluate the success of myoblast transplantation is described. The method takes advantage of a unified fusion reporter gene composed of genes whose expression can be imaged with different imaging modalities. Here, we make use of a fluc reporter gene sequence to target cells via bioluminescence imaging.

移植筋前駆細胞を標的とする分子イメージング

Duchenne muscular dystrophy (DMD) is a severe genetic neuromuscular disorder that affects 1 in 3,500 boys, and is characterized by progressive muscle ...

In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

Macrophages are key-cells in the initiation, the development and the regulation of the inflammatory response to bacterial infection. Macrophages are intensively and increasingly recruited in septic joints from the early phases of infection and the infiltration is supposed to regress once efficient removal of the pathogens is obtained. The ability to identify in vivo macrophage activity in an infected joint can therefore provide two main applications: early detection of acute synovitis and monitoring of therapy.
In vivo noninvasive detection of macrophages can be performed with magnetic resonance imaging using iron nanoparticles such as ultrasmall superparamagnetic iron oxide (USPIO). After intravascular or intraarticular administration, USPIO are specifically phagocytized by activated macrophages, and, due to their magnetic properties, induce signal changes in tissues presenting macrophage infiltration. A quantitative evaluation of the infiltrate is feasible, as the area with signal loss (number of dark pixels) observed on gradient echo MR images after particles injection is correlated with the amount of iron within the tissue and therefore reflects the number of USPIO-loaded cells.
We present here a protocol to perform macrophage imaging using USPIO-enhanced MR imaging in an animal model of septic arthritis, allowing an initial and longitudinal in vivo noninvasive evaluation of macrophages infiltration and an assessment of therapy action.

In vivo Macrophage Imaging Using MR Targeted Contrast Agent for Longitudinal Evaluation of Septic Arthritis

We demonstrate how to perform macrophage MR imaging using ultrasmall superparamagnetic contrast agent (USPIO) in septic arthritis, allowing an initial and longitudinal in vivo non-invasive evaluation of macrophages infiltration and an assessment of therapy efficacy.

敗血症性関節炎の経時的評価のためにMRターゲット造影剤を用いたin vivoイメージングのマクロファージ

Macrophages are key-cells in the initiation, the development and the regulation of the inflammatory response to bacterial infection. Macrophages are ...

An Orthotopic Murine Model of Human Prostate Cancer Metastasis

Our laboratory has developed a novel orthotopic implantation model of human prostate cancer (PCa). As PCa death is not due to the primary tumor, but rather the formation of distinct metastasis, the ability to effectively model this progression pre-clinically is of high value. In this model, cells are directly implanted into the ventral lobe of the prostate in Balb/c athymic mice, and allowed to progress for 4-6 weeks. At experiment termination, several distinct endpoints can be measured, such as size and molecular characterization of the primary tumor, the presence and quantification of circulating tumor cells in the blood and bone marrow, and formation of metastasis to the lung. In addition to a variety of endpoints, this model provides a picture of a cells ability to invade and escape the primary organ, enter and survive in the circulatory system, and implant and grow in a secondary site. This model has been used effectively to measure metastatic response to both changes in protein expression as well as to response to small molecule therapeutics, in a short turnaround time.

This orthotopic model of human prostate cancer allows for quantification of tumor size, circulating tumor cells, and formation of distinct metastasis to the lung. As cells must escape the primary organ, enter the blood stream, and implant into a secondary site, this model effectively recapitulates the scenario in humans.

ヒト前立腺癌転移の同所マウスモデル

Our laboratory has developed a novel orthotopic implantation model of  human prostate cancer (PCa). As PCa death is not due to the primary tumor, but  ...

Isolation of Cancer Stem Cells From Human Prostate Cancer Samples

The cancer stem cell (CSC) model has been considerably revisited over the last two decades. During this time CSCs have been identified and directly isolated from human tissues and serially propagated in immunodeficient mice, typically through antibody labeling of subpopulations of cells and fractionation by flow cytometry. However, the unique clinical features of prostate cancer have considerably limited the study of prostate CSCs from fresh human tumor samples. We recently reported the isolation of prostate CSCs directly from human tissues by virtue of their HLA class I (HLAI)-negative phenotype. Prostate cancer cells are harvested from surgical specimens and mechanically dissociated. A cell suspension is generated and labeled with fluorescently conjugated HLAI and stromal antibodies. Subpopulations of HLAI-negative cells are finally isolated using a flow cytometer. The principal limitation of this protocol is the frequently microscopic and multifocal nature of primary cancer in prostatectomy specimens. Nonetheless, isolated live prostate CSCs are suitable for molecular characterization and functional validation by transplantation in immunodeficient mice.

The isolation of cancer stem cells (CSCs) directly from human tissues is requisite for their biological characterization. This manuscript describes a methodology for the isolation of prostate CSCs from human tissues, while also providing tips on troubleshooting difficult steps.

ヒト前立腺癌サンプルからがん幹細胞の単離

The cancer stem cell (CSC) model has been considerably revisited over the last two decades. During this time CSCs have been identified and directly ...

Dynamic Contrast Enhanced Magnetic Resonance Imaging of an Orthotopic Pancreatic Cancer Mouse Model

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) has been limitedly used for orthotopic pancreatic tumor xenografts due to severe respiratory motion artifact in the abdominal area. Orthotopic tumor models offer advantages over subcutaneous ones, because those can reflect the primary tumor microenvironment affecting blood supply, neovascularization, and tumor cell invasion. We have recently established a protocol of DCE-MRI of orthotopic pancreatic tumor xenografts in mouse models by securing tumors with an orthogonally bent plastic board to prevent motion transfer from the chest region during imaging. The pressure by this board was localized on the abdominal area, and has not resulted in respiratory difficulty of the animals. This article demonstrates the detailed procedure of orthotopic pancreatic tumor modeling using small animals and DCE-MRI of the tumor xenografts. Quantification method of pharmacokinetic parameters in DCE-MRI is also introduced. The procedure described in this article will assist investigators to apply DCE-MRI for orthotopic gastrointestinal cancer mouse models.

The goal of this protocol is to apply dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for orthotopic pancreatic tumor xenografts in mice. DCE-MRI is a non-invasive method to analyze microvasculature in a target tissue, and useful to assess vascular response in a tumor following a novel therapy.

同所膵臓癌マウスモデルのダイナミックコントラスト強化磁気共鳴画像

Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) has been limitedly used for orthotopic pancreatic tumor xenografts due to severe ...

Generation of Prostate Cancer Patient Derived Xenograft Models from Circulating Tumor Cells

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, biologic studies, and personalized medicine strategies. Circulating tumor cells (CTC) play a critical role in tumor metastasis and have been isolated from patients with several tumor types. Recently, CTCs have been used to generate PDX experimental models of breast and prostate cancer. This manuscript details the method for the generation of prostate cancer PDX models from CTCs developed by our group. Advantages of this method over conventional PDX models include independence from surgical sample collection and generating experimental models at various disease stages. Density gradient centrifugation followed by red blood cell lysis and flow cytometry depletion of CD45 positive mononuclear cells is used to enrich CTCs from peripheral blood samples collected from patients with metastatic disease. The CTCs are then injected into immunocompromised mice; subsequently generated xenografts can be used for functional studies or harvested for molecular characterization. The primary limitation of this method is the negative selection method used for CTC enrichment. Despite this limitation, the generation of PDX models from CTCs provides a novel experimental model to be applied to prostate cancer research.

This manuscript details a method used to generate prostate cancer patient derived xenografts (PDXs) from circulating tumor cells (CTCs). The generation of PDX models from CTCs provides an alternative experimental model to study prostate cancer; the most commonly diagnosed tumor and a frequent cause of death from cancer in men.

前立腺癌患者の発生は、循環腫瘍細胞からの異種移植モデルを派生します

Patient derived xenograft (PDX) models are gaining popularity in cancer research and are used for preclinical drug evaluation, biomarker identification, ...

A Brain Tumor/Organotypic Slice Co-culture System for Studying Tumor Microenvironment and Targeted Drug Therapies

Brain tumors are a major cause of cancer-related morbidity and mortality. Developing new therapeutics for these cancers is difficult, as many of these tumors are not easily grown in standard culture conditions. Neurosphere cultures under serum-free conditions and orthotopic xenografts have expanded the range of tumors that can be maintained. However, many types of brain tumors remain difficult to propagate or study. This is particularly true for pediatric brain tumors such as pilocytic astrocytomas and medulloblastomas. This protocol describes a system that allows primary human brain tumors to be grown in culture. This quantitative assay can be used to investigate the effect of microenvironment on tumor growth, and to test new drug therapies. This protocol describes a system where fluorescently labeled brain tumor cells are grown on an organotypic brain slice from a juvenile mouse. The response of tumor cells to drug treatments can be studied in this assay, by analyzing changes in the number of cells on the slice over time. In addition, this system can address the nature of the microenvironment that normally fosters growth of brain tumors. This brain tumor organotypic slice co-culture assay provides a propitious system for testing new drugs on human tumor cells within a brain microenvironment.

Many types of human brain tumors are localized to specific regions within the brain and are difficult to grow in culture. This protocol addresses the role of tumor microenvironment and investigates new drug treatments by analyzing fluorescent primary brain tumor cells growing in an organotypic mouse brain slice. &#160;

腫瘍微小環境と標的薬物療法研究のための脳の腫瘍/器官スライス共培養系

Brain tumors are a major cause of cancer-related morbidity and mortality. Developing new therapeutics for these cancers is difficult, as many of these ...