This work was supported by grants from the JDRF (1-2008-994, 27-2012-450) and the National Institutes of Health (R01DK096492-05, R21AI124488-01, T32OD012201, and F30OD021477).

ヒトPBMCの1の単離<ol><li>ヘパリン処理した採血管を用いて血液30〜50ミリリットル集めます。 注：使用される血液の量は、目的の抗原特異的B細胞の血液中の特定の実験的な質問と周波数に依存します。ヘパリン化血液はすぐに処理されるか、または翌日処理するために、室温で一晩穏やかに揺動させることができます。処理の遅延は、濃縮の効率にはほとんど影響があり、生存能力の最小の損失と関連しています。 </li><li>無菌、室温マグネシウムおよびカルシウムを含まないリン酸緩衝生理食塩水（PBS）で1：全血1を混ぜます。 </li><li> 50ミリリットル滅菌コニカルチューブで、室温密度勾配溶液10mlを加えます。 4℃で暗所で開かれた密度勾配ボトルを保管しますが、使用前に室温に温めます。 </li><li>可能であれば、ゆっくりと遅い設定にピペットガンを設定し、および/または非常に少ない、まだ一貫性を適用し、トリガ圧2を混ぜないように注意しながら、密度勾配の上に希釈した血液30〜35ミリリットル層。 注：希釈血液を添加しながら、50ミリリットルの円錐形の端にピペットの先端を配置するには、一貫性のある安定した流れを確保するのに役立ちます。 </li><li>ブレーキと20℃で30分間、400×gで遠心分離がオフになっています。 </li><li>以下の単核細胞層を乱さないように注意しながら、血漿および血小板が含まれている上層を、削除します。 </li><li>滅菌ピペットを用いて、単核細胞層（軟膜）を収集し、別々の滅菌50mlコニカルチューブに配置します。 </li><li> 50ミリリットルの体積に細胞懸濁液にPBSを追加します。ブレーキと20℃で10分間、400×gで遠心分離します。 </li><li>上清を除去し、10mlのPBSでペレット化した細胞を再懸濁します。細胞を計数し、血球計または自動細胞カウンターを用いて生存率を測定。 </li><li>さらなる処理のための直前まで、10 7細胞/ mlで、氷上での場所で細胞を再懸濁し。</li></ol>細胞の2染色<ol><li>該当する場合は、必要に応じて各蛍光補正/ FMOの制御のために1〜2×10 6個の細胞を除去します。ブレーキと4℃で10分間、400×gで細胞の遠心分離余り。 </li><li> 3-6×10 7細胞/ mlで滅菌濾過し、冷FACS緩衝液（PBS + 1％ウシ血清アルブミン（BSA）+ 0.01％アジ化ナトリウム）中で再懸濁細胞を（1.5 ml遠心チューブに取り除きます）。 FACS緩衝液が冷えていることを確認し、染色手順を通じて氷上に保管してください。 <ol><li>アッセイを最適化する際に四分の（AD）への細胞集団を分割します。濃縮/染色の特異性を決定するために、関心、使用画分BとCの抗原特異的B細胞を濃縮するために、画分Aを使用して、抗原特異的細胞の頻度および数を決定するために、使用画分D（2.5以下2.6を参照のこと）利回りの計算を可能にし、折り畳み式濃縮をする未濃縮集団。 </li></ol></li><li>人間のFcγR遮断再追加Fc受容体に対する抗体の結合を防ぐために、氷の上での分画のADへの薬剤。 注：適切な条件については、製造元の指示に従ってください。 </li><li>クロスする蛍光色素を含まないように注意しながら、暗所で氷上で30分間の分画のADへの関心の細胞表面抗原に対する蛍光標識抗体を加えるには、磁性ナノ粒子に結合した抗遠赤蛍光色素抗体と反応します。 注：これらは、近赤外蛍光色素、Cy5を、Cy5.5標識、及びCy7のに抗体複合体が含まれます。追加された生存能力の汚れは固定液の使用に適合するものでなければなりません。一つELISPOTによって、例えば、FACSを用いて細胞を分析したが、抗体分泌周波数を決定することを意図していない場合は、抗体を用いた表面染色は不要です。 </li><li>アッセイの特異性を試験氷上で30分間、未標識の抗原の十分な量の画分Bをインキュベートし、その結果の親和性を有する受容体の大部分は、少なくとも10 -6 Mはブロックされます。 注：一般的に、良い出発濃度（ 例えば 50〜100μM）を下回る2.6で十分とみなされる抗原の量の50から100倍過剰です。これは、このように濃縮された細胞の特異性の確認を可能にする、以下のステップ2.6で添加されるビオチン化抗原に結合する非標識抗原に対して高い親和性を有する任意のB細胞を阻止すべきです。このステップは、ステップ上記2.4と組み合わせて完成させることができます。 </li><li> 30分間氷上で画分A、B、およびDインキュベートにビオチン化抗原を追加します。 注：ビオチン化抗原の濃度は、適切な検出および非特異的バイスタンダー細胞から結合細胞の分離を確実にするために必要とされる最適量を決定するために滴定されるべきです。典型的には、テストに良い出発濃度は1〜5μMです。 注：画分AとDの場合、このステップは、ステップ上記2.4と同時に行うことができます。画分Bの場合は、このステップはbetwのステップ2.5（洗浄後に行われるべきですEENステップ）が不要です。 </li><li>そのようなストレプトアビジン遠赤蛍光色素や磁性ビーズなどのプロトコルで他の試薬へのB細胞の結合を決定するために、画分Cからのビオチン化抗原を省略します。 </li><li> 4℃で5分間、400×gでの冷FACSの5×10 7個の細胞当たりのバッファと遠心分離の1ミリリットル中に細胞懸濁液により細胞を2回洗浄します。 </li><li>最終洗浄後、5×10 7個の細胞当たり1ミリリットルの2％ホルムアルデヒド中で濃縮された細胞懸濁液を希釈し、5分間氷上で暗所に放置します。 注：この時点で細胞の固定は、ビオチン化抗原は、手順の残りのためのBCRに結合したままであることが保証されます。生細胞について - 下流の分析のために、このようなELISPOTSまたは養子の転送のように、固定工程を省略します。 </li><li> 4℃で5分間、400×gで二回コールドFACSの5×10 7個の細胞当たりのバッファと遠心機の1ミリリットルで細胞を洗浄。 1ミリリットル中に再懸濁し、5×10あたりの冷FACS緩衝液7細胞。 </li><li> 1-2μgのストレプトアビジン - 遠赤蛍光色素/ mlの追加、暗所で20分間氷上でインキュベートします。各アプリケーションのためのストレプトアビジンの量を滴定します。 </li><li> 4℃で5分間、400×gで1ミリリットルの冷FACSの5×10 7個の細胞当たりのバッファと遠心で細胞を2回洗浄します。それは、磁気ビーズを使用して濃縮を受けないように、画分Dの調製は、この時点で終了します。 注：このサンプルは、サンプル中の抗原特異的B細胞の頻度および数を決定するために使用されます。これは、濃縮することにより達成-濃縮を倍収量を決定するために使用されます。 </li></ol> 3.磁性ナノ粒子ベースの濃縮<ol><li> 5×10 7個の細胞当たりの冷分離緩衝液の1ミリリットル（PBS + 0.5％BSA + 2mMのEDTA）中のサンプルACからの細胞を再懸濁し、カラムを詰まらせる可能性の塊を除去するために40μmのフィルターを通過します。 </li><li>アンチのCy5 /アンチ遠赤蛍光色素ナノ粒子を追加します。フォー最適な結果をR、ナノ粒子の濃度は、それぞれの使用のために滴定されるべきであるが、良好な出発点は、5×10 7細胞/ ml当たり50μlの懸濁液です。 10分間、4℃で暗所に回転させます。 </li><li> 4℃で5分間、400×gでで1 mlの冷分離緩衝液で2回洗浄します。 5×10 7個の細胞当たりの冷分離緩衝液1ml中の細胞を再懸濁し。 </li></ol> LSまたはLDカラムを用い4.磁気濃縮<ol><li>磁気分離器の磁場中で3 LSまたはLD列を配置し、列を濡らす分離緩衝液の3ミリリットルを追加（列の型が最適であるかを決定するには製品の説明を参照してください）。すべての3ミリリットルがカラムを通過し、収集した後に破棄できるようにします。 注：磁性ナノ粒子の分離標識された細胞は、市販されている磁気分離装置のいずれかを使用して達成することができるが、実験室ではTEに、LSカラムを用いて、最も成功を収めています濃縮の収率、純度、および効率のrms。 </li><li>列の下、マイナスに選択したセルのために標識3 15ミリリットルコニカルチューブ「画分A /（B）/（C）負」を配置します。それぞれの列に磁性粒子標識細胞を追加し、ボリューム全体を通過させます。 </li><li>上に冷たい分離バッファーの3ミリリットルを追加し、これはカラムを通過し、2ミリリットルで繰り返すことができます。負の選択された細胞を収集し、氷上に取っておきます。 </li><li>磁場から列を削除し、積極的に選択したセルのための「画分A /（B）/（C）正」は、標識された15ミリリットルコニカルチューブの上に置きます。 </li><li>約6ミリリットル分離緩衝液ので先頭に列を記入し、すぐに提供するプランジャーを用いた磁気フィールドにバインドした細胞を収集するために、カラムを介してこのボリュームを急落。 </li><li>純度を高めるために、積極的に選択された細胞は、さらにproceを繰り返し、第二の清浄なカラムを用いて濃縮することができますdure。 </li><li> 4℃で10分間、400×gで負及び正に選択された画分の両方を回転し、所望の最終容積に懸濁します。このようなFACS、ELISPOTまたは養子移入として、下流の分析を進めてください。 </li></ol>

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The authors declare they have no competing financial interests.

ここでは、ヒト末梢血由来の抗原結合性B細胞の単離および濃縮を達成する新規な方法を記載します。この方法は、マウスに、そのような脾臓およびリンパ節など他の組織に容易に適用可能であり、細胞表現型および機能（原稿準備中）の後濃縮分析と互換性があります。 ユーザーは、この手順の成功に影響を与えることができる変数の数を認識すべきです。経験から死?...

限界希釈する抗体分泌細胞の前駆体頻度の分析は、特定の抗原に対して反応性B細胞は、典型的には、ワクチン接種の状態と抗原上に存在するエピトープのサイズ/数に応じて、通常のレパートリーは0.05〜0.005％の頻度で起こることを示唆しています。これらの細胞の低頻度は、それが難しいような外来抗原、または自己免疫の開発中に、次のワクチン接種または暴露のような免疫応答の開発中にその状態の変化を研究するために作られました。以前に、研究者らは、抗原被覆プレートまたはカラムの吸着剤から、抗原でコーティングされた赤血球のリセットに、1、2、3、4、5を蛍光活性化細胞選別、6の範囲の技術を用いて抗原反応性B細胞の単離を行っています。 Thougこれらの技術は、抗原反応性B細胞を同定及び単離に成功している時間は、その結果は、収率、純度およびスケーラビリティの点で変化しています。最近では、両方の検出および磁性ナノ粒子を用いた希少なBリンパ球亜集団を豊かにする新規な方法を開発しました。この方法は、大きな始動集団からの比較的高い収率および純度で濃縮を可能にし、抗原に対する応答の解析と互換性があります。懸濁液中の細胞の集団から豊かにすることで、この方法は、抗原をコーティングしたプレートまたは列、および限界スループットのジオメトリに関連付けられている制約を排除します。濃縮された細胞は、抗原および蛍光レポーターに関連付けられたままであるので、最終的に、彼らはさらに、FACS選別によって精製することができます。本明細書に記載するように、私たちは前に、末梢血破傷風トキソイド反応性B細胞の研究のために、このアプローチを使用し、様々なautoiを有する被験者からヒト被験者の免疫化、ならびに自己反応性B細胞を、次のしています1型糖尿病、バセドウ病、橋本病7を含むmmune障害、。この方法は、マウスおよびヒトで同様に動作し、種々の組織（原稿準備中）からの抗原反応性B細胞の解析と互換性があります。 その基本的な形式では、末梢血単核細胞を、最初に表現型分析のために必要な表面抗原、細胞に対する抗体と一緒にビオチン化抗原と共にインキュベートします。この標識工程は、洗浄及び固定に続いて、ストレプトアビジンを添加する（ 図1）ビオチン化抗原結合細胞の検出のための遠赤色蛍光色素に結合されています。以前の研究は同様に、抗原特異的B細胞を同定したが、直接蛍光色素8、9、10、11に結合させた抗原を用いています。これは価値があるが、アプローチは、ストレプトアビジンと組み合わせたビオチン化抗原の使用は、抗原は12、13、14小さい場合は特に、大きな信号増幅（結合および非結合細胞の、したがってより良い差別化）を可能にします。追加の考慮事項は、ストレプトアビジンの代わりにストレプトアビジンが脱グリコシル化されているので、非特異的結合を減少させるの使用です。さらに、我々は、その光安定、量子収率（明るさ）、およびその小さなサイズ（〜1.3キロダルトン）に蛍光色素として遠赤蛍光染料を使用しています。彼らは潜在的に多くの抗原性エピトープを含んでいるので、このようなフィコエリトリン（〜250キロダルトン）およびアロフィコシアニン（〜105 kD）の15のようなタンパク質の蛍光色素は最適ではありません。このような遠赤色蛍光色素として、単一のエピトープからなる小有機蛍光色素の使用は、単離された細胞集団の複雑性を低減します。 細胞がされるとビオチン化-Antigenと遠赤蛍光色素 - ストレプトアビジン吸着は、それらが抗遠赤蛍光色素結合磁性ナノ粒子を使用して濃縮されています。シングルナノ粒子は、ほとんどのフローサイトメーターによって検出されていないため、FACSソーティングと下流のアッセイ16による精製の前に除去する必要はありません。抗原特異的なB細胞のための磁気選択、フローサイトメーターを使用して稀なイベントを選別する時間とコストを排除する、関心の集団を濃縮します。 我々は前と7日破傷風トキソイドの追加免疫後に被験者からの破傷風トキソイド特異的B細胞の濃縮から代表的な結果を示し、以下に。我々は、in vivo刺激における急性以下の抗原特異的B細胞を濃縮するために、この方法の能力を実証するために、一例として、この特定のアプリケーションを選択しました。フローサイトメトリーと組み合わせると、この方法は、抗原特異的ナイーブ、メモリを濃縮し、分化することが可能であり、かつ形質B細胞および研究者が時間をかけて自分の周波数の変化に追従することができます。また、我々は、 例えば、細胞は、濃縮後の抗体を分泌する能力を保持することを実証するELISPOTアッセイ、別の可能な下流アッセイを含みます。この方法の別の用途は、宿主に濃縮された細胞の養子移入を伴う可能性があります。我々は以前に、細胞が単離および転送次抗原特異的T細胞を抗原提示細胞として作用する能力を維持示した（データ示さず）。したがって、一緒に抗原特異的免疫応答の理解を通知する方法、に結合することができる可能な下流アッセイの数があります。我々は全体の収率、純度、細胞特異性、および折り畳み式濃縮を決定するための制御を含む、以下の方法を、記載しています。

<table border="0" cellpadding="0" cellspacing="0" width="594">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="99">
			<td height="99" style="height:99px;width:164px;">Antigen of interest</td>
			<td style="width:104px;">variable</td>
			<td style="width:131px;">variable</td>
			<td style="width:196px;">At least 100 &#956;g to biotinylate easily; if using protein try to use protein that has been validated by ELISA. It must be carrier&#160; protein free.</td>
		</tr>
		<tr height="118">
			<td height="118" style="height:118px;width:164px;">Biotin for labeling; e.g. EZ link Sulfo-NHS-LC-Biotin</td>
			<td style="width:104px;">e.g. Thermo Scientific</td>
			<td style="width:131px;">e.g. 21335</td>
			<td style="width:196px;">Biotin is available in different formulations, such as those containing&#160; various length spacers, so the type used should be determined by the researcher</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:164px;">Streptavidin-Alexa Fluor 647</td>
			<td style="width:104px;">Invitrogen</td>
			<td style="width:131px;">S21374</td>
			<td style="width:196px;">Can obtain from other suppliers.</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:164px;">Anti-Cy5/Anti-Alexa Fluor 647 Microbeads</td>
			<td style="width:104px;">Miltenyi Biotech</td>
			<td style="width:131px;">130-091-395</td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="39">
			<td height="39" style="height:39px;width:164px;">LS Columns</td>
			<td style="width:104px;">Miltenyi Biotech</td>
			<td style="width:131px;">130-042-401</td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="44">
			<td height="44" style="height:44px;width:164px;">MACS manual separators</td>
			<td style="width:104px;">Miltenyi Biotech</td>
			<td style="width:131px;">variable</td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="71">
			<td height="71" style="height:71px;width:164px;">Formaldehyde</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;">Dilute to 2% with PBS; optional if downstream assay requires live cells</td>
		</tr>
		<tr height="50">
			<td height="50" style="height:50px;width:164px;">PBS without calcium and magnesium</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="33">
			<td height="33" style="height:33px;width:164px;">Ficoll-Paque PLUS</td>
			<td style="width:104px;">GE Healthcare</td>
			<td style="width:131px;">17-1440-02</td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="59">
			<td height="59" style="height:59px;width:164px;">Whole blood in heparinized collection tubes</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="69">
			<td height="69" style="height:69px;width:164px;">FACS buffer (PBS + 1% BSA + 0.01% sodium azide)</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="64">
			<td height="64" style="height:64px;width:164px;">Separation buffer (PBS + 0.5% BSA + 2mM EDTA)</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:164px;">50 mL conical tubes</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="26">
			<td height="26" style="height:26px;width:164px;">15 mL conical tubes</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="23">
			<td height="23" style="height:23px;width:164px;">1.5 mL Eppendorf tubes</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="96">
			<td height="96" style="height:96px;width:164px;">Surface marker&#160; reactive antibodies, Fc Block, live/dead discriminating stain, if needed</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
		<tr height="38">
			<td height="38" style="height:38px;width:164px;">ELISPOT supplies, if needed</td>
			<td style="width:104px;"></td>
			<td style="width:131px;"></td>
			<td style="width:196px;"></td>
		</tr>
	</tbody>
</table>

detection and enrichment of rare antigen-specific b cells for analysis of phenotype and function

B cells reactive with a specific antigen usually occur at a frequency of &lt;0.05% of lymphocytes. For decades researchers have sought methods to isolate and enrich these rare cells for studies of their phenotype and biology. Approaches are inevitably based on the principle that B cells recognize native antigen by virtue of cell surface receptors that are representative in specificity of antibodies that will eventually be secreted by their differentiated daughters. Perhaps the most obvious approach to the problem involves use of fluorochrome-conjugated antigens in conjunction with fluorescence-activated cell sorting (FACS). However, the utility of these methods is limited by cell frequency and the achievable rate of analysis and isolation by electronic sorting. A novel method to enrich rare antigen-specific B cells using magnetic nanoparticles that results in high yield enrichment of antigen-reactive B cells from large starting cell populations is described. This method enables improved monitoring of the phenotype and biology of antigen reactive cells before and following in vivo antigen encounter, such as after immunization or during development of autoimmunity.

純度、収量の分析、および倍富化フローサイトメトリーを用いて、 必然的に、ストレプトアビジン遠赤蛍光色素を結合しなかったが、マトリックス中に捕捉されている混入細胞が含まれている上記のように濃縮された集団。これらの不純物は、FACSソーティングにより濃縮された集団から除去することができます。濃縮され?...

Watch this Scientific Journal Video about Detection and Enrichment of Rare Antigen-specific B Cells for Analysis of Phenotype and Function at JoVE.com

Detection and Enrichment of Rare Antigen-specific B Cells for Analysis of Phenotype and Function

機能的および表現型分析のために、抗原反応性B細胞を検出し、豊かに磁性ナノ粒子を使用するシンプルで効果的な方法が記載されています。

表現型および機能解析のためのレア抗原特異的B細胞の検出および濃縮

B cells reactive with a specific antigen usually occur at a frequency of &lt;0.05% of lymphocytes. For decades researchers have sought methods to isolate ...

detection-enrichment-rare-antigen-specific-b-cells-for-analysis

Research

JoVE Journal

Immunology and Infection

11.3K ビュー.  University of Colorado School of Medicine. 機能的および表現型分析のために、抗原反応性B細胞を検出し、豊かに磁性ナノ粒子を使用するシンプルで効果的な方法が記載されています。 

ビデオ: Detection and Enrichment of Rare Antigen-specific B Cells for Analysis of Phenotype and Function

Murine Model of CD40-activation of B cells

Research on B cells has shown that CD40 activation improves their antigen presentation capacity. When stimulated with interleukin-4 and CD40 ligand (CD40L), human B cells can be expanded without difficulties from small amounts of peripheral blood within 14 days to very large amounts of highly-pure CD40-B cells (&gt;109 cells per patient) from healthy donors as well as cancer patients1-4. CD40-B cells express important lymph node homing molecules and can attract T cells in vitro5. Furthermore they efficiently take up, process and present antigens to T cells6,7. CD40-B cells were shown to not only prime na&iacute;ve, but also expand memory T cells8,9. Therefore CD40-activated B cells (CD40-B cells) have been studied as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cell-based immunotherapy1,5,10. In order to further study whether CD40-B cells induce effective T cell responses in vivo and to study the underlying mechanism we established a cell culture system for the generation of murine CD40-activated B cells. Using splenocytes or purified B cells from C57BL/6 mice for CD40-activation, optimal conditions were identified as follows: Starting from splenocytes of C57BL/6 mice (haplotype H-2b) lymphocytes are purified by density gradient centrifugation and co-cultured with HeLa cells expressing recombinant murine CD40 ligand (tmuCD40L HeLa)11. Cells are recultured every 3-4 days and key components such as CD40L, interleukin-4, -Mercaptoethanol and cyclosporin A are replenished. In this protocol we demonstrate how to obtain fully activated murine CD40-B cells (mCD40B) with similar APC-phenotype to human CD40-B cells (Fig 1a,b). CD40-stimulation leads to a rapid outgrowth and expansion of highly pure (&gt;90%) CD19+ B cells within 14 days of cell culture (Fig 1c,d). To avoid contamination with non-transfected cells, expression of the murine CD40 ligand on the transfectants has to be controlled regularly (Fig 2). Murine CD40-activated B cells can be used to study B-cell activation and differentiation as well as to investigate their potential to function as APC in vitro and in vivo. Moreover, they represent a promising tool for establishing therapeutic or preventive vaccination against tumors and will help to answer questions regarding safety and immunogenicity of this approach12.

In this video, we demonstrate the procedure of CD40-activation and expansion of murine B cells from splenocytes of C57BL/6 mice, which can be used as a model antigen-presenting cell (APC) to study induction of immunity.

B細胞のCD40 -活性化のモデルマウス

Research on B cells has shown that CD40 activation improves their antigen presentation capacity. When stimulated with interleukin-4 and CD40 ligand ...

免疫・感染学

Antigen Specific In Vivo Killing Assay using CFSE Labeled Target Cells

Carboxyfluorescein diacetate succinimidyl ester (CFSE) can be used to easily and quickly label a cell population of interest for in vivo investigation. This labeling has classically been used to study proliferation and migration. In the method presented here, we have shortened the timeline after adoptive transfer to look at survival and killing of epitope specific CFSE labeled target cells4-6. The level of specific killing of a CD8 + T cell clone can indicate the quality of the response, as their quantity may be misleading. Specific CD8+ T cells can become functionally exhausted over time with a decline in cytokine production and killing7,8. Also, certain CD8 + T cell clones may not kill as well as others with differing TCR specificities9. For effective Cell Mediated Immunity (CMI), antigens must be identified that produce not only adequate numbers of responding T cells, but also functionally robust responding T cells. Here we assess the percent cell specific killing of two peptide specific T cell clones in BALB/c mice.

Antigen Specific In Vivo Killing Assay using CFSE Labeled Target Cells

Many infections elicit a strong CTL response, but occasionally, the quantity of responding cells does not correlate to control of the pathogen1. One measure of CTL quality is their ability to kill specifically2. CFSE labeling of target cells can be used to investigate this CTL response quality in vivo3,4.

抗原特異的インビボでの</emCFSE標識した標的細胞を用いた>キリングアッセイ

Carboxyfluorescein diacetate succinimidyl ester (CFSE) can be used to easily and quickly label a cell population of interest for in vivo investigation.  ...

Trans-vivo Delayed Type Hypersensitivity Assay for Antigen Specific Regulation

Delayed-type hypersensitivity response (DTH) is a rapid in vivo manifestation of T cell-dependent immune response to a foreign antigen (Ag) that the host immune system has experienced in the recent past. DTH reactions are often divided into a sensitization phase, referring to the initial antigen experience, and a challenge phase, which usually follows several days after sensitization. The lack of a delayed-type hypersensitivity response to a recall Ag demonstrated by skin testing is often regarded as an evidence of anergy. The traditional DTH assay has been effectively used in diagnosing many microbial infections.
Despite sharing similar immune features such as lymphocyte infiltration, edema, and tissue necrosis, the direct DTH is not a feasible diagnostic technique in transplant patients because of the possibility of direct injection resulting in sensitization to donor antigens and graft loss. To avoid this problem, the human-to-mouse "trans-vivo" DTH assay was developed 1,2. This test is essentially a transfer DTH assay, in which human peripheral blood mononuclear cells (PBMCs) and specific antigens were injected subcutaneously into the pinnae or footpad of a na&iuml;ve mouse and DTH-like swelling is measured after 18-24 hr 3. The antigen presentation by human antigen presenting cells such as macrophages or DCs to T cells in highly vascular mouse tissue triggers the inflammatory cascade and attracts mouse immune cells resulting in swelling responses. The response is antigen-specific and requires prior antigen sensitization. A positive donor-reactive DTH response in the Tv-DTH assay reflects that the transplant patient has developed a pro-inflammatory immune disposition toward graft alloantigens.
The most important feature of this assay is that it can also be used to detect regulatory T cells, which cause bystander suppression. Bystander suppression of a DTH recall response in the presence of donor antigen is characteristic of transplant recipients with accepted allografts 2,4-14. The monitoring of transplant recipients for alloreactivity and regulation by Tv-DTH may identify a subset of patients who could benefit from reduction of immunosuppression without elevated risk of rejection or deteriorating renal function.
A promising area is the application of the Tv-DTH assay in monitoring of autoimmunity15,16 and also in tumor immunology 17.

We describe a valuable diagnostic assay that could potentially be used to decide the withdrawal of immunosuppression after transplant without elevated risk of graft rejection. The assay uses the principles of Delayed Type Hypersensitivity and provides accurate assessment of both donor specific effector and regulatory immune responses mounted by recipients.

抗原特異的規制用のトランス生体内遅延型過敏アッセイ

Delayed-type hypersensitivity response (DTH) is a rapid in vivo manifestation of T cell-dependent immune response to a foreign antigen (Ag) that the host ...

Killer Artificial Antigen Presenting Cells (KaAPC) for Efficient In Vitro Depletion of Human Antigen-specific T Cells

Current treatment of T cell mediated autoimmune diseases relies mostly on strategies of global immunosuppression, which, in the long term, is accompanied by adverse side effects such as a reduced ability to control infections or malignancies. Therefore, new approaches need to be developed that target only the disease mediating cells and leave the remaining immune system intact. Over the past decade a variety of cell based immunotherapy strategies to modulate T cell mediated immune responses have been developed. Most of these approaches rely on tolerance-inducing antigen presenting cells (APC). However, in addition to being technically difficult and cumbersome, such cell-based approaches are highly sensitive to cytotoxic T cell responses, which limits their therapeutic capacity. Here we present a protocol for the generation of non-cellular killer artificial antigen presenting cells (KaAPC), which allows for the depletion of pathologic T cells while leaving the remaining immune system untouched and functional. KaAPC is an alternative solution to cellular immunotherapy which has potential for treating autoimmune diseases and allograft rejections by regulating undesirable T cell responses in an antigen specific fashion.

Killer Artificial Antigen Presenting Cells KaAPC for Efficient In Vitro Depletion of Human Antigen-specific T Cells

Guidelines are presented for the generation of killer artificial antigen presenting cells, KaAPC, an efficient tool for in vitro depletion of human antigen-specific T cells and an alternative solution to cellular immunotherapy for the treatment of T cell-mediated autoimmune diseases in an antigen-specific fashion without compromising the remaining immune system.

効率的なためキラー人工抗原提示細胞（KaAPC）<em&gt;体外</em&gt;ヒト抗原特異的T細胞の枯渇

Current treatment of T cell mediated autoimmune diseases relies mostly on strategies of global immunosuppression, which, in the long term, is accompanied ...

Detection of True IgE-expressing Mouse B Lineage Cells

B lymphocyte immunoglobulin heavy chain (IgH) class switch recombination (CSR) is a process wherein initially expressed IgM switches to other IgH isotypes, such as IgA, IgE and IgG. Measurement of IgH CSR in vitro is a key method for the study of a number of biologic processes ranging from DNA recombination and repair to aspects of molecular and cellular immunology. In vitro CSR assay involves the flow cytometric measurement surface Ig expression on activated B cells. While measurement of IgA and IgG subclasses is straightforward, measurement of IgE by this method is problematic due to soluble IgE binding to Fc&#949;RII/CD23 expressed on the surface of activated B cells. Here we describe a unique procedure for accurate measurement of IgE-producing mouse B cells that have undergone CSR in culture. The method is based on trypsin-mediated cleavage of IgE-CD23 complexes on cell surfaces, allowing for detection of IgE-producing B lineage cells by cytoplasmic staining. This procedure offers a convenient solution for flow cytometric analysis of CSR to IgE.

In vitro analysis of class switch recombination in mice is challenging due to cytophilic IgE molecules bound to Fc receptors on the surface of B cells. We describe a method for IgE detection using trypsin-mediated cleavage of surface-bound IgE prior to fixation and permeabilization for cytoplasmic fluorescence staining.

真のIgE発現するマウスB系統細胞の検出

B lymphocyte immunoglobulin heavy chain (IgH) class switch recombination (CSR) is a process wherein initially expressed IgM switches to other IgH ...

Whole-animal Imaging and Flow Cytometric Techniques for Analysis of Antigen-specific CD8+ T Cell Responses after Nanoparticle Vaccination

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various nanoparticle systems have been engineered to mimic features of pathogens to improve antigen delivery to draining lymph nodes and increase antigen uptake by antigen-presenting cells, leading to new vaccine formulations optimized for induction of antigen-specific CD8+ T cell responses. In this article, we describe the synthesis of a &#8220;pathogen-mimicking&#8221; nanoparticle system, termed interbilayer-crosslinked multilamellar vesicles (ICMVs) that can serve as an effective vaccine carrier for co-delivery of subunit antigens and immunostimulatory agents and elicitation of potent cytotoxic CD8+ T lymphocyte (CTL) responses. We describe methods for characterizing hydrodynamic size and surface charge of vaccine nanoparticles with dynamic light scattering and zeta potential analyzer and present a confocal microscopy-based procedure to analyze nanoparticle-mediated antigen delivery to draining lymph nodes. Furthermore, we show a new bioluminescence whole-animal imaging technique utilizing adoptive transfer of luciferase-expressing, antigen-specific CD8+ T cells into recipient mice, followed by nanoparticle vaccination, which permits non-invasive interrogation of expansion and trafficking patterns of CTLs in real time. We also describe tetramer staining and flow cytometric analysis of peripheral blood mononuclear cells for longitudinal quantification of endogenous T cell responses in mice vaccinated with nanoparticles.

We describe whole-animal imaging and flow cytometry-based techniques for monitoring expansion of antigen-specific CD8+ T cells in response to immunization with nanoparticles in a murine model of vaccination.

ナノ粒子ワクチン接種後の抗原特異的CD8 + T細胞応答の分析のための全動物イメージングとフローサイトメトリー技術

Traditional vaccine adjuvants, such as alum, elicit suboptimal CD8+ T cell responses. To address this major challenge in vaccine development, various ...

Development of Stem Cell-derived Antigen-specific Regulatory T Cells Against Autoimmunity

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic self-tolerance. Tregs represent about 5 - 10% of the mature CD4+ T cell subpopulation in mice and humans, with about 1 - 2% of those Tregs circulating in the peripheral blood. Induced pluripotent stem cells (iPSCs) can be differentiated into functional Tregs, which have a potential to be used for cell-based therapies of autoimmune diseases. Here, we present a method to develop antigen (Ag)-specific Tregs from iPSCs (i.e., iPSC-Tregs). The method is based on incorporating the transcription factor FoxP3 and an Ag-specific T cell receptor (TCR) into iPSCs and then differentiating on OP9 stromal cells expressing Notch ligands delta-like (DL) 1 and DL4. Following in vitro differentiation, the iPSC-Tregs express CD4, CD8, CD3, CD25, FoxP3, and Ag-specific TCR and are able to respond to Ag stimulation. This method has been successfully applied to cell-based therapy of autoimmune arthritis in a murine model. Adoptive transfer of these Ag-specific iPSC-Tregs into Ag-induced arthritis (AIA)-bearing mice has the ability to reduce joint inflammation and swelling and to prevent bone loss.

We present here a method to develop functional antigen (Ag)-specific regulatory T cells (Tregs) from induced pluripotent stem cells (iPSCs) for immunotherapy of autoimmune arthritis in a murine model.

自己免疫に対する幹細胞由来の抗原特異的制御性T細胞の開発

Autoimmune diseases arise due to the loss of immunological self-tolerance. Regulatory T cells (Tregs) are important mediators of immunologic ...

In Situ MHC-tetramer Staining and Quantitative Analysis to Determine the Location, Abundance, and Phenotype of Antigen-specific CD8 T Cells in Tissues

T cells are critical to many immunological processes, including detecting and eliminating virus-infected cells, preventing autoimmunity, assisting in B-cell and plasma-cell production of antibodies, and detecting and eliminating cancer cells. The development of MHC-tetramer staining of antigen-specific T cells analyzed by flow cytometry has revolutionized our ability to study and understand the immunobiology of T cells. While extremely useful for determining the quantity and phenotype of antigen-specific T cells, flow cytometry cannot determine the spatial localization of antigen-specific T cells to other cells and structures in tissues, and current disaggregation techniques to extract the T cells needed for flow cytometry have limited effectiveness in non-lymphoid tissues. In situ MHC-tetramer staining (IST) is a technique to visualize T cells that are specific for antigens of interest in tissues. In combination with immunohistochemistry (IHC), IST can determine the abundance, location, and phenotype of antigen-specific CD8 and CD4 T cells in tissues. Here, we describe a protocol to stain and enumerate antigen-specific CD8 T cells, with specific phenotypes located within specific tissue compartments. These procedures are the same that we used in our recent publication by Li et al., entitled &#34;Simian Immunodeficiency Virus-Producing Cells in Follicles Are Partially Suppressed by CD8+ Cells In Vivo.&#34; The methods described are broadly applicable because they can be used to localize, phenotype, and quantify essentially any antigen-specific CD8 T cell for which MHC tetramers are available, in any tissue.

In Situ MHC-tetramer Staining and Quantitative Analysis to Determine the Location, Abundance, and Phenotype of Antigen-specific CD8 T Cells in Tissues

Here, we describe a method that combines in situ MHC-tetramer staining with immunohistochemistry to determine localization, phenotype, and quantity of antigen-specific T cells in tissues. This protocol is used to determine the spatial and phenotypic characteristics of antigen-specific CD8 T cells relative to other cell type and structures in tissues.

その場でMHC テトラマー染色と場所、豊富と組織における抗原特異的 cd8 陽性 T 細胞の表現型を決定するための定量解析

T cells are critical to many immunological processes, including detecting and eliminating virus-infected cells, preventing autoimmunity, assisting in ...

In Vivo Assay for Detection of Antigen-specific T-cell Cytolytic Function Using a Vaccination Model

Current methodologies for antigen-specific killing are limited to in vitro use or utilized in infectious disease models. However, there is not a protocol specifically intended to measure antigen-specific killing without an infection. This protocol is designed and describes methods to overcome these limitations by allowing for the detection of antigen-specific killing of a target cell by CD8+ T cells in vivo. This is accomplished by merging a vaccination model with a traditional CFSE-labeled target killing assay. This combination allows the researcher to assess the antigen-specific CTL potential directly and quickly as the assay is not dependent upon tumor growth or infection. In addition, the readout is based on flow cytometry and so should be readily accessible to most researchers. The major limitation of the study is identifying the timeline in vivo that is appropriate to the hypothesis being tested. Variations in antigen strength and mutations in the T cells that may result in differential cytolytic function need to be carefully assessed to determine the optimal time for cell harvest and assessment. The appropriate concentration of peptide for vaccination has been optimized for hgp10025-33 and OVA257-264, but further validation would be needed for other peptides that may be more appropriate to a given study. Overall, this protocol allows a quick assessment of killing function in vivo and can be adapted to any given antigen.

In Vivo Assay for Detection of Antigen-specific T-cell Cytolytic Function Using a Vaccination Model

The goal of this protocol is to allow for detection of in vivo antigen-specific killing of a target cell in a murine model.

生体内で予防接種モデルを用いた抗原特異的 T 細胞細胞傷害性関数の検出のための試金

Current methodologies for antigen-specific killing are limited to in vitro use or utilized in infectious disease models. However, there is not a protocol ...

Generation of Discriminative Human Monoclonal Antibodies from Rare Antigen-specific B Cells Circulating in Blood

Monoclonal antibodies (mAbs) are powerful tools useful for both fundamental research and in biomedicine. Their high specificity is indispensable when the antibody needs to distinguish between highly related structures (e.g., a normal protein and a mutated version thereof). The current way of generating such discriminative mAbs involves extensive screening of multiple Ab-producing B cells, which is both costly and time consuming. We propose here a rapid and cost-effective method for the generation of discriminative, fully human mAbs starting from human blood circulating B lymphocytes. The originality of this strategy is due to the selection of specific antigen binding B cells combined with the counter-selection of all other cells, using readily available Peripheral Blood Mononuclear Cells (PBMC). Once specific B cells are isolated, cDNA (complementary deoxyribonucleic acid) sequences coding for the corresponding mAb are obtained using single cell Reverse Transcription-Polymerase Chain Reaction (RT-PCR) technology and subsequently expressed in human cells. Within as little as 1 month, it is possible to produce milligrams of highly discriminative human mAbs directed against virtually any desired antigen naturally detected by the B cell repertoire.

We describe a method for the production of human antibodies specific for an antigen of interest, starting from rare B cells circulating in human blood. Generation of these natural antibodies is efficient and rapid, and the antibodies obtained can discriminate between highly related antigens.

まれな抗原特異的 B 細胞血液の循環から弁別に対するモノクローナル抗体の生成

Monoclonal antibodies (mAbs) are powerful tools useful for both fundamental research and in biomedicine. Their high specificity is indispensable when the ...