The author would like to thank the NIH Tetramer Core Facility for tetramer production. The author would also like to thank E.D. O&#8217;Connor and K.E. Marquez at the UCSD Human Embryonic Stem Cell Core Facility flow cytometry laboratory for assistance in cell sorting. This work was funded by National Institutes of Health grant K08AI085039 (G.P.M.).

<ol>
	<li>Smith-Garvin, J. E., Koretzky, G. A., Jordan, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=T+cell+activation.">T cell activation.</a> Annu. Rev. Immunol. 27 (1), 591-619 (2009).</li><li>Morris, G. P., Allen, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+the+TCR+balances+sensitivity+and+specificity+for+the+recognition+of+self+and+pathogens.">How the TCR balances sensitivity and specificity for the recognition of self and pathogens.</a> Nat. Immunol. 13 (2), 121-128 (2012).</li><li>Arstilla, T. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+direct+estimation+of+the+human+&#945;&#946;+T+cell+receptor+diversity.">A direct estimation of the human &#945;&#946; T cell receptor diversity.</a> Science. 286 (5441), 958-961 (1999).</li><li>Robbins, H. S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+assessment+of+T-cell+receptor+&#946;-chain+diversity+in+&#945;&#946;+T+cells.">Comprehensive assessment of T-cell receptor &#946;-chain diversity in &#945;&#946; T cells.</a> Blood. 114 (19), 4099-4107 (2009).</li><li>Alanio, C., Lemaitre, F., Law, H. K. W., Hasan, M., Albert, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enumeration+of+human+antigen-specific+naive+CD8++T+cells+reveals+conserved+precursor+frequencies.">Enumeration of human antigen-specific naive CD8+ T cells reveals conserved precursor frequencies.</a> Blood. 115 (18), 3718-3725 (2010).</li><li>Suchin, E. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quantifying+the+frequency+of+alloreactive+T+cells+in+vivo:+new+answers+to+an+old+question.">Quantifying the frequency of alloreactive T cells in vivo: new answers to an old question.</a> J. Immunol. 166 (2), 973-981 (2001).</li><li>Felix, N. J., Allen, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+of+T-cell+alloreactivity.">Specificity of T-cell alloreactivity.</a> Nat. Rev. Immunol. 7 (12), 942-953 (2007).</li><li>Morris, G. P., Ni, P. P., Allen, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alloreactivity+is+limited+by+the+endogenous+peptide+repertoire.">Alloreactivity is limited by the endogenous peptide repertoire.</a> Proc. Natl. Acad. Sci. USA. 108 (9), 3695-3700 (2011).</li><li>Suri, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+APCs,+the+autologous+peptides+selected+by+the+diabetogenic+I-Ag7+molecule+are+unique+and+determined+by+the+amino+acid+changes+in+the+P9+pocket.">In APCs, the autologous peptides selected by the diabetogenic I-Ag7 molecule are unique and determined by the amino acid changes in the P9 pocket.</a> J. Immunol. 168 (3), 1235-1243 (2002).</li><li>Yssl, H., Spits, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+and+maintenance+of+cloned+human+T+cell+lines.">Generation and maintenance of cloned human T cell lines.</a> Curr. Protoc. Immunol. 7, (2002).</li><li>Altman, J. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phenotypic+analysis+of+antigen-specific+T+lymphocytes.">Phenotypic analysis of antigen-specific T lymphocytes.</a> Science. 274 (5284), 94-96 (1996).</li><li>Moon, J. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Naive+CD4++T+cell+frequency+varies+for+different+epitopes+and+predicts+repertoire+diversity+and+response+magnitude.">Naive CD4+ T cell frequency varies for different epitopes and predicts repertoire diversity and response magnitude.</a> Immunity. 27 (2), 203-213 (2007).</li><li>Chicz, R. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specificity+and+promiscuity+among+naturally+processed+peptides+bound+to+HLA-DR+alleles.">Specificity and promiscuity among naturally processed peptides bound to HLA-DR alleles.</a> J. Exp. Med. 178 (1), 27-47 (1993).</li><li>Ni, P. P., Allen, P. M., Morris, G. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+ability+to+rearrange+dual+TCRs+enhances+positive+selection,+leading+to+increased+allo-+and+autoreactive+T+cell+repertoires.">The ability to rearrange dual TCRs enhances positive selection, leading to increased allo- and autoreactive T cell repertoires.</a> J. Immunol. In press, (2014).</li><li>Morris, G. P., Uy, G. L., Donermeyer, D., DiPersio, J. F., Allen, P. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual+receptor+T+cells+mediate+pathologic+alloreactivity+in+patients+with+acute+graft-versus-host+disease.">Dual receptor T cells mediate pathologic alloreactivity in patients with acute graft-versus-host disease.</a> Sci. Transl. Med. 5 (188), (2013).</li><li>Altman, J. D., Reay, P. A., Davis, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Formation+of+functional+peptide+complexes+of+class+II+major+histocompatibility+complex+proteins+from+subunits+produced+in+Escherichia+coli.">Formation of functional peptide complexes of class II major histocompatibility complex proteins from subunits produced in Escherichia coli.</a> Proc. Natl. Acad. Sci. USA. 90 (21), 10330-10334 (1993).</li><li>Sabatino, J. J., Huang, J., Zhu, C., Evavold, B. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+prevalence+of+low+affinity+peptide-MHC+II+tetramer-negative+effectors+during+polyclonal+CD4++T+cell+responses.">High prevalence of low affinity peptide-MHC II tetramer-negative effectors during polyclonal CD4+ T cell responses.</a> J. Exp. Med. 208 (1), 81-90 (2011).</li></ol>

The authors declare no competing financial interests.

T cell alloreactivity is a long-studied and clinically-relevant phenomenon. The robust proliferative and effector responses of T cells to allogeneic stimulation has enabled extensive analyses of human T cell responses in vitro through relatively straightforward mixed lymphocyte reactions of peripheral blood T cells against inactivated allogeneic cells. However, these primary alloreactive T cell responses are oligoclonal, comprised of a large number of individual T cells responding to specific alloantigens. This ...

الخلايا اللمفية تي هي مكونات أساسية في الجهاز المناعي التكيفي. خلايا T هي المسئولة عن ليس فقط التوسط مباشرة استجابات مناعية وقائية لمسببات الأمراض من خلال مجموعة متنوعة من الآليات المستجيب، ولكن أيضا الحفاظ بنشاط التسامح المناعي الذاتي وتوجيه استجابات خلايا أخرى في جهاز المناعة. يتم توجيه هذه الوظائف من خلال عدد من الإشارات متكاملة، بما في ذلك مستقبلات الخلايا التائية (TCR) ربط، والسيتوكينات كيموكينات، والأيض 1. من هذه الإشارات، وTCR له أهمية خاصة، حيث أنه يوفر خصوصية المميزة التي تحدد دور الخلايا التائية في المناعة التكيفية. يتفاعل مع مستضدات TCR الببتيد الخطية التي قدمها MHC (HLA ortholog البشري) جزيئات (المجمعات PMHC) بطريقة محددة جدا وحساسة لتوفير الإشارات التي تبدأ T وظيفة الخلايا المستجيب. المعلمات البيوكيميائية من التفاعلات مع TCR بروابط رهن العقاري توفر ليس فقط خصوصية لTتنشيط الخلايا، ولكن أيضا أن يكون لها تأثير نوعي على وظيفة خلايا T لاحقا 2. وبالتالي، دراسة وظيفة خلايا T وغالبا ما يتطلب دراسة استجابات الخلايا التائية نسيلي مع خصوصية محددة المستضدات. تي المقصورة الخلية البشرية، التي تحتوي على ما يقرب من 10 12 خلايا T αβ، ويحتوي على ما يقدر بنحو 10 يوليو - 10 أغسطس αβTCRs متميزة 3-4. يوفر هذا ذخيرة متنوعة فرصة للاعتراف مجموعة واسعة من الببتيدات من مسببات الأمراض المحتملة التي من شأنها أن تتطلب استجابة خلايا T للمناعة وقائية. وتشير التقديرات إلى أن وتيرة خلايا تي الاستجابة لمستضد الأجانب نظرا قدمها MHC الذاتي هو بناء على أمر من 10 -4 - 10 -7 في غياب الاستجابة المناعية قبل أن مستضد 5. يتشكل من السذاجة الخلايا التائية ذخيرة عن طريق الانتقاء الغدة الصعترية لضمان القدرة على التعرف على الذات MHC تقديم المستضدات الببتيد والحد تتفاعلivity ضد المستضدات الببتيد الذاتي، وتعظيم الفائدة المحتملة للوساطة مناعة وقائية 2. ومع ذلك، في انتهاك لهذا التفاعل تصميم، تردد كبير نسبيا، 10 -3 - 10 -4، خلايا تي من الأفراد ساذج مناعيا الرد على التحفيز مع خلايا الاعضاء المختلفة وراثيا، والاعتراف كلا من جزيئات MHC الأجنبية وكذلك الببتيدات الذاتية ما يقدمونه 6. الاعتراف بروابط PMHC خيفي يشبه هيكليا إلى الاعتراف مستضدات أجنبية قدمها MHC على الذات؛ وTCR يجعل التفاعلات الكيميائية الحيوية الهامة مع كل من الجزيء MHC خيفي فضلا عن تقديمها 7 الببتيد. مجمعات الطبيعة القوية لاستجابة خلايا T إلى نتائج التحفيز خيفي من تنوع PMHC موجودة على سطح الخلايا خيفي 8. ويقدر أن كل MHC يقدم حوالي 2 × 10 4 مختلف المستضدات الذاتية الببتيد 9. هذا بreadth الاستجابة للتحفيز خيفي هو جانب هام من أمراض سريريا ذات الصلة، مثل رفض المزروع أو الكسب غير المشروع مقابل المرض المضيف (GVHD)، الناتجة عن الخلايا التائية alloreactivity. دراسة استجابات الخلايا التائية alloreactive الإنسان قد اعتمدت تقليديا على دراسة الردود بولكلونل خلايا T ساذجة التالية التحفيز مع خلايا خيفي. التحفيز المتكرر مع نفس خط الخلية خيفي جنبا إلى جنب مع الحد من التخفيف يحلل قادر على توليد خلايا T نسيلي مع الاعتراف محددة من خيفي HLA 10. ومع ذلك، فإن هذا النهج هو مشكلة لدراسة الردود على الفرد بروابط PMHC خيفي، ومرجع كبير ومتنوع من الذاتية PMHC مجمعات الحالي لخيفي نظرا HLA يحفز ذخيرة واسعة من خلايا تي. وهذا من شأنه تحفيز السكان السائبة والحد من نهج التخفيف تتطلب فحص أعداد كبيرة من الحيوانات المستنسخة لعزل خلايا T مع reacti المطلوبvity ضد PMHC يجند احد. بالإضافة إلى ذلك، تردد خلايا تي الاستجابة لفرد خيفي PMHC يجند منخفض نسبيا بين السكان السذاجة الخلايا التائية، مما يشكل عائقا أمام جيل فعال من استنساخ الخلايا التائية البشرية تستجيب لمستضد معين. وقد مكن تحديد وعزل خلايا T مستضد معين من السكان بولكلونل من خلال تطوير المسمى fluorophore PMHC multimers 11. هذا النهج يستخدم المضادات الببتيد محددة تحميلها في المؤتلف للذوبان جزيئات MHC المعقدة البيروكسيديز، والتي وصفت من قبل الملزم إلى fluorophore المسمى streptavidin. Multimerization للرهن العقاري يزيد من الطمع، وتعويض عن انخفاض جوهري (ميكرومتر) تقارب من TCR للرهن العقاري بروابط القابلة للذوبان. ويمكن تحديد وعزل الخلايا المسمى من قبل التدفق الخلوي. ومع ذلك، فإن هذا النهج لا تزال محدودة بسبب التردد المنخفض من خلايا تي مستضد معين بين السكان السذاجة الخلايا التائية، والتي عادة ما تكونأوامر من حجم أقل من الحد من تحديد دقيق وتقدير على معظم أجهزة قياس التدفق الخلوي. لمعالجة هذا القيد، تم تطوير طريقة للرهن العقاري ووضع العلامات tetramer احق تخصيب حبة المغناطيسي للخلايا المسمى tetramer 12. وقد أثبتت هذه الطريقة الكشف موثوق بها، تعداد، وعزل خلايا T مستضد معين التردد المنخفض. يصف هذا البروتوكول بروتوكول فعال لتوليد استنساخ الإنسان خلايا T التي تستجيب خصيصا لالفردية بروابط PMHC خيفي. ينطبق البروتوكول رهن العقاري (HLA) متعدد القسيمات وضع العلامات وإثراء لعزل خلايا T الإنسان مستضد خيفي خاصة مع التدفق الخلوي خلية الفرز وسيلة قوية للثقافة في المختبر من خلايا T البشرية لتمكين إنتاج تي استنساخ خلية من خلايا مرتبة واحدة ( نظرة عامة في الشكل 1).

<table border="0" cellpadding="0" cellspacing="0" width="907">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Name of Reagent/ Equipment</td>
			<td style="width:223px;">Company</td>
			<td style="width:119px;">Catalog Number</td>
			<td style="width:292px;">Comments/Description</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:273px;">Sodium heparin venous blood collection tube 16 x 100 mm</td>
			<td style="width:223px;">Becton, Dickenson and Company</td>
			<td style="width:119px;">366480</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Lymphoprep</td>
			<td style="width:223px;">Stemcell Technologies</td>
			<td style="width:119px;">7801</td>
			<td></td>
		</tr>
		<tr height="27">
			<td height="27" style="height:27px;width:273px;">Rosette Sep Human T Cell Enrichment Kit</td>
			<td style="width:223px;">Stemcell Technologies</td>
			<td style="width:119px;">15061</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Dulbecco&#39;s PBS, 1x without Ca or Mg</td>
			<td style="width:223px;">Corning</td>
			<td style="width:119px;">21-031-CV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Bovine serum albumin</td>
			<td style="width:223px;">Sigma-Aldrich</td>
			<td style="width:119px;">A7906</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">EDTA</td>
			<td style="width:223px;">Sigma-Aldrich</td>
			<td style="width:119px;">E6635</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Fluorophore-labeled pMHC tetramer</td>
			<td style="width:223px;">NIH Tetramer Facility</td>
			<td style="width:119px;">NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">EasySep Biotin Selection Kit</td>
			<td style="width:223px;">Stemcell Technologies</td>
			<td style="width:119px;">18553</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">EasySep Selection magnet</td>
			<td style="width:223px;">Stemcell Technologies</td>
			<td style="width:119px;">18000</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:273px;">TruStain FcX Human Fc blocking solution</td>
			<td style="width:223px;">Biolegend</td>
			<td style="width:119px;">422301</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Anti-CD5 PE-Cy7 (clone UCHT2)</td>
			<td style="width:223px;">Biolegend</td>
			<td style="width:119px;">300621</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Anti-CD14 FITC (clone HCD14)</td>
			<td style="width:223px;">Biolegend</td>
			<td style="width:119px;">325603</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Anti-CD19 FITC (clone HIB19)</td>
			<td style="width:223px;">Biolegend</td>
			<td style="width:119px;">302205</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:273px;">Iscove&#39;s DMEM, without b-ME or L-glutamine</td>
			<td style="width:223px;">Corning</td>
			<td style="width:119px;">15-016-CV</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">HEPES</td>
			<td style="width:223px;">Corning</td>
			<td style="width:119px;">25-060-CI</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">b-Mercaptoethanol&#160;</td>
			<td style="width:223px;">Life Technologies</td>
			<td style="width:119px;">21985-023</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Glutamax</td>
			<td style="width:223px;">Life Technologies</td>
			<td style="width:119px;">35050061</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Gentamicin sulfate (50 mg/ml)</td>
			<td style="width:223px;">Omega Scientific</td>
			<td style="width:119px;">GT-50</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Human AB serum, male donor</td>
			<td style="width:223px;">Omega Scientific</td>
			<td style="width:119px;">HS-30</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Recombinant human IL-2</td>
			<td style="width:223px;">Peprotech</td>
			<td style="width:119px;">AF 200-02</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:273px;">Dynabeads Human T-Activator CD3/CD28</td>
			<td style="width:223px;">Life Technologies</td>
			<td style="width:119px;">11131D</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;"></td>
			<td style="width:223px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Media</td>
			<td style="width:223px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Cell sorting buffer</td>
			<td style="width:223px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">PBS, pH 7.4</td>
			<td style="width:223px;">1 L</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">BSA</td>
			<td style="width:223px;">10g</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">EDTA (0.5 M)</td>
			<td style="width:223px;">2 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;"></td>
			<td style="width:223px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Human T Cell Culture Medium</td>
			<td style="width:223px;"></td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Iscove&#39;s DMEM</td>
			<td style="width:223px;">351.6 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Heat-inactivated human AB serum</td>
			<td style="width:223px;">40 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">HEPES (1 M)</td>
			<td style="width:223px;">4 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Glutamax (100 x)</td>
			<td style="width:223px;">4 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Gentamicin (50 mg/ml)</td>
			<td style="width:223px;">0.4 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">b-mercaptoethanol (14.3 M)</td>
			<td style="width:223px;">1.4 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:273px;">Recombinant human IL-2 (1 mg/ml)</td>
			<td style="width:223px;">1 ml</td>
			<td style="width:119px;"></td>
			<td></td>
		</tr>
	</tbody>
</table>

generation of human alloantigen-specific t cells from peripheral blood

The study of human T lymphocyte biology often involves examination of responses to activating ligands. T cells recognize and respond to processed peptide antigens presented by MHC (human ortholog HLA) molecules through the T cell receptor (TCR) in a highly sensitive and specific manner. While the primary function of T cells is to mediate protective immune responses to foreign antigens presented by self-MHC, T cells respond robustly to antigenic differences in allogeneic tissues. T cell responses to alloantigens can be described as either direct or indirect alloreactivity. In alloreactivity, the T cell responds through highly specific recognition of both the presented peptide and the MHC molecule. The robust oligoclonal response of T cells to allogeneic stimulation reflects the large number of potentially stimulatory alloantigens present in allogeneic tissues. While the breadth of alloreactive T cell responses is an important factor in initiating and mediating the pathology associated with biologically-relevant alloreactive responses such as graft versus host disease and allograft rejection, it can preclude analysis of T cell responses to allogeneic ligands. To this end, this protocol describes a method for generating alloreactive T cells from naive human peripheral blood leukocytes (PBL) that respond to known peptide-MHC (pMHC) alloantigens. The protocol applies pMHC multimer labeling, magnetic bead enrichment and flow cytometry to single cell in vitro culture methods for the generation of alloantigen-specific T cell clones. This enables studies of the biochemistry and function of T cells responding to allogeneic stimulation.

يصف هذا البروتوكول الجيل الثقافات الخلايا التائية البشرية نسيلي مع خصوصية محددة مستضد خيفي عبر تخصيب حبة المغناطيسي والتدفق الخلوي وحيدة الخلية فرز استراتيجية الشكل 1 يقدم الخطوط العريضة للعملية. <i...

Watch this Scientific Journal Video about Generation of Human Alloantigen-specific T Cells from Peripheral Blood at JoVE.com

Generation of Human Alloantigen-specific T Cells from Peripheral Blood

This article describes a method for the generation and propagation of human T cell clones that specifically respond to a defined alloantigen. This protocol can be adapted for cloning human T cells specific for a variety of peptide-MHC ligands.

توليد خلايا T الإنسان مستضد خيفي محددة من الدم المحيطي

The study of human T lymphocyte biology often involves examination of responses to activating ligands. T cells recognize and respond to processed peptide ...

generation-of-human-alloantigen-specific-t-cells-from-peripheral-blood

Research

JoVE Journal

Immunology and Infection

12.9K Views.  University of California, San Diego. This article describes a method for the generation and propagation of human T cell clones that specifically respond to a defined alloantigen. This protocol can be adapted for cloning human T cells specific for a variety of peptide-MHC ligands.

Video: Generation of Human Alloantigen-specific T Cells from Peripheral Blood

Expansion, Purification, and Functional Assessment of Human Peripheral Blood NK Cells

Natural killer (NK) cells play an important role in immune surveillance against a variety of infectious microorganisms and tumors. Limited availability of NK cells and ability to expand in vitro has restricted development of NK cell immunotherapy. Here we describe a method to efficiently expand vast quantities of functional NK cells ex vivo using K562 cells expressing membrane-bound IL21, as an artificial antigen-presenting cell (aAPC).
NK cell adoptive therapies to date have utilized a cell product obtained by steady-state leukapheresis of the donor followed by depletion of T cells or positive selection of NK cells. The product is usually activated in IL-2 overnight and then administered the following day 1. Because of the low frequency of NK cells in peripheral blood, relatively small numbers of NK cells have been delivered in clinical trials.
The inability to propagate NK cells in vitro has been the limiting factor for generating sufficient cell numbers for optimal clinical outcome. Some expansion of NK cells (5-10 fold over 1-2 weeks) has be achieved through high-dose IL-2 alone 2. Activation of autologous T cells can mediate NK cell expansion, presumably also through release of local cytokine 3. Support with mesenchymal stroma or artificial antigen presenting cells (aAPCs) can support the expansion of NK cells from both peripheral blood and cord blood 4. Combined NKp46 and CD2 activation by antibody-coated beads is currently marketed for NK cell expansion (Miltenyi Biotec, Auburn CA), resulting in approximately 100-fold expansion in 21 days.
Clinical trials using aAPC-expanded or -activated NK cells are underway, one using leukemic cell line CTV-1 to prime and activate NK cells5 without significant expansion. A second trial utilizes EBV-LCL for NK cell expansion, achieving a mean 490-fold expansion in 21 days6. The third utilizes a K562-based aAPC transduced with 4-1BBL (CD137L) and membrane-bound IL-15 (mIL-15)7, which achieved a mean NK expansion 277-fold in 21 days. Although, the NK cells expanded using K562-41BBL-mIL15 aAPC are highly cytotoxic in vitro and in vivo compared to unexpanded NK cells, and participate in ADCC, their proliferation is limited by senescence attributed to telomere shortening8. More recently a 350-fold expansion of NK cells was reported using K562 expressing MICA, 4-1BBL and IL159.
Our method of NK cell expansion described herein produces rapid proliferation of NK cells without senescence achieving a median 21,000-fold expansion in 21 days.

Here we describe a method to efficiently expand and purify large numbers of human NK cells and assess their function.

توسيع وتنقية ، والتقييم الوظيفي للخلايا الدم المحيطية الإنسان NK

Natural killer (NK) cells play an important role in immune surveillance against a variety of infectious microorganisms and tumors. Limited availability of ...

Induction of Alloantigen-specific Anergy in Human Peripheral Blood Mononuclear Cells by Alloantigen Stimulation with Co-stimulatory Signal Blockade

Allogeneic hematopoietic stem cell transplantation (AHSCT) offers the best chance of cure for many patients with congenital and acquired hematologic diseases. Unfortunately, transplantation of alloreactive donor T cells which recognize and damage healthy patient tissues can result in Graft-versus-Host Disease (GvHD)1. One challenge to successful AHSCT is the prevention of GvHD without associated impairment of the beneficial effects of donor T cells, particularly immune reconstitution and prevention of relapse. GvHD can be prevented by non-specific depletion of donor T cells from stem cell grafts or by administration of pharmacological immunosuppression. Unfortunately these approaches increase infection and disease relapse2-4. An alternative strategy is to selectively deplete alloreactive donor T cells after allostimulation by recipient antigen presenting cells (APC) before transplant. Early clinical trials of these allodepletion strategies improved immune reconstitution after HLA-mismatched HSCT without excess GvHD5, 6. However, some allodepletion techniques require specialized recipient APC production6, 7and some approaches may have off-target effects including depletion of donor pathogen-specific T cells8and CD4 T regulatory cells9.One alternative approach is the inactivation of alloreactive donor T cells via induction of alloantigen-specific hyporesponsiveness. This is achieved by stimulating donor cells with recipient APC while providing blockade of CD28-mediated co-stimulation signals10.This "alloanergization" approach reduces alloreactivity by 1-2 logs while preserving pathogen- and tumor-associated antigen T cell responses in vitro11. The strategy has been successfully employed in 2 completed and 1 ongoing clinical pilot studies in which alloanergized donor T cells were infused during or after HLA-mismatched HSCT resulting in rapid immune reconstitution, few infections and less severe acute and chronic GvHD than historical control recipients of unmanipulated HLA-mismatched transplantation12. Here we describe our current protocol for the generation of peripheral blood mononuclear cells (PBMC) which have been alloanergized to HLA-mismatched unrelated stimulator PBMC. Alloanergization is achieved by allostimulation in the presence of monoclonal antibodies to the ligands B7.1 and B7.1 to block CD28-mediated costimulation. This technique does not require the production of specialized stimulator APC and is simple to perform, requiring only a single and relatively brief ex vivo incubation step. As such, the approach can be easily standardized for clinical use to generate donor T cells with reduced alloreactivity but retaining pathogen-specific immunity for adoptive transfer in the setting of AHSCT to improve immune reconstitution without excessive GvHD.

This paper describes a simple technique to induce alloantigen-specific anergy in human peripheral blood mononuclear cells. The technique can be applied clinically to generate non-alloreactive donor cells. Infusion of these cells could improve immune reconstitution and reduce toxicity after allogeneic hematopoietic stem cell transplantation.

تحريض مستضد خيفي محددة استعطال الإنسان في خلايا الدم المحيطية وحيدات النوى التي تحفيز مستضد خيفي مع حصار العلامة المشارك تنشيطية

Allogeneic hematopoietic stem cell transplantation (AHSCT) offers the best chance of cure for many patients with congenital and acquired hematologic ...

Expansion of Human Peripheral Blood  &gamma;&delta; T Cells using Zoledronate

Human &gamma;&delta; T cells can recognize and respond to a wide variety of stress-induced antigens, thereby developing innate broad anti-tumor and anti-infective activity.1 The majority of &gamma;&delta; T cells in peripheral blood have the V&gamma;9V&delta;2 T cell receptor. These cells recognize antigen in a major histocompatibility complex-independent manner and develop strong cytolytic and Th1-like effector functions.1Therefore, &gamma;&delta; T cells are attractive candidate effector cells for cancer immunotherapy. V&gamma;9V&#x03B4;2 T cells respond to phosphoantigens such as (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), which is synthesized in bacteria via isoprenoid biosynthesis;2 and isopentenyl pyrophosphate (IPP), which is produced in eukaryotic cells through the mevalonate pathway.3 In physiological condition, the generation of IPP in nontransformed cell is not sufficient for the activation of &gamma;&delta; T cells. Dysregulation of mevalonate pathway in tumor cells leads to accumulation of IPP and &gamma;&delta; T cells activation.3 Because aminobisphosphonates (such as pamidronate or zoledronate) inhibit farnesyl pyrophosphate synthase (FPPS), the enzyme acting downstream of IPP in the mevalonate pathway, intracellular levels of IPP and sensitibity to &gamma;&delta; T cells recognition can be therapeutically increased by aminobisphosphonates. IPP accumulation is less efficient in nontransfomred cells than tumor cells with a pharmacologically relevant concentration of aminobisphosphonates, that allow us immunotherapy for cancer by activating &gamma;&delta; T cells with aminobisphosphonates. 4 Interestingly, IPP accumulates in monocytes when PBMC are treated with aminobisphosphonates, because of efficient drug uptake by these cells. 5 Monocytes that accumulate IPP become antigen-presenting cells and stimulate V&gamma;9V&delta;2 T cells in the peripheral blood.6 Based on these mechanisms, we developed a technique for large-scale expansion of &gamma;&delta; T cell cultures using zoledronate and interleukin-2 (IL-2).7 Other methods for expansion of &gamma;&delta; T cells utilize the synthetic phosphoantigens bromohydrin pyrophosphate (BrHPP)8 or 2-methyl-3-butenyl-1-pyrophosphate (2M3B1PP).9 All of these methods allow ex vivo expansion, resulting in large numbers of &gamma;&delta; T cells for use in adoptive immunotherapy. However, only zoledronate is an FDA-approved commercially available reagent. Zoledronate-expanded &gamma;&delta; T cells display CD27-CD45RA- effector memory phenotype and thier function can be evaluated by IFN-&gamma; production assay. 7

Expansion of Human Peripheral Blood  &amp;#947;&amp;#948; T Cells using Zoledronate

A method to expand &gamma;&delta; T cells from peripheral blood mononuclear cells (PBMC) is described. PBMC-derived &gamma;&delta; T cells are stimulated and expanded using zoledronate and interleukin-2 (IL-2). Large scale expansion of &gamma;&delta; T cells can be applied to autologous cellular immunotherapy of cancer.

التوسع في الدم المحيطي الإنسان خلايا T γδ باستخدام Zoledronate

Human &gamma;&delta; T cells can recognize and respond to a wide variety of stress-induced antigens, thereby developing innate broad anti-tumor and ...

Generation of Induced Regulatory T Cells from Primary Human Na&iuml;ve and Memory T Cells

The development and maintenance of immunosuppressive CD4+ regulatory T cells (Tregs) contribute to the peripheral tolerance needed to remain in immunologic homeostasis with the vast amount of self and commensal antigens in and on the human body. Perturbations in the balance between Tregs and inflammatory conventional T cells can result in immunopathology or cancer. Although therapeutic injection of Tregs has been shown to be efficacious in murine models of colitis1 , type I diabetes2 , rheumatoid arthritis and graft versus host disease,4 several fundamental differences in human versus mouse Treg biology5 has thus far precluded clinical use. The lack of sufficient number, purity, stability and homing specificity of therapeutic Tregs necessitated a dynamic platform of human Treg development on which to optimize conditions for their ex vivo expansion6.
Here we describe a method for the differentiation of induced Tregs (iTregs) from a single human peripheral blood donor which can be broken down into four stages: isolation of peripheral blood mononuclear cells, magnetic selection of CD4+ T cells, in vitro cell culture and fluorescence activated cell sorting (FACS) of T cell subsets. Since the Treg signature transcription factor forkhead box P3 (FoxP3) is an activation-induced transcription factor in humans7 and no other unique marker exists, a combinatorial panel of markers must be used to identify T cells with suppressor activity. After six days in culture, cells in our system can be demarcated into na&iuml;ve T cells, memory T cells or iTregs based on their relative expression of CD25 and CD45RA. As memory and na&iuml;ve T cells have different reported polarization requirements and plasticities8 , pre-sorting of the initial T cell population into CD45RA+ and CD45RO+ subsets can be used to examine these discrepancies. Consistent with others, our CD25HiCD45RA- iTregs express high levels of FoxP39 , GITR and CTLA-411 and low levels of CD12712 . Following FACS of each population, resultant cells can be used in a suppressor assay which evaluates the relative ability to retard the proliferation of carboxyfluorescein succinimidyl ester (CFSE)-labeled autologous T cells.

Generation of Induced Regulatory T Cells from Primary Human Na&amp;#239;ve and Memory T Cells

We describe a method for generating regulatory, memory and na&#239;ve T cells from a single human blood donor. Polarized Tregs can be then compared to other subsets in a variety of genetic and functional applications with genetic homogeneity, including a suppression assay also detailed here.

جيل من الخلايا المستحثة تي التنظيمية من المرحلة الابتدائية الإنسان خلايا T ساذجة والذاكرة

The development and maintenance of immunosuppressive CD4+ regulatory T cells (Tregs) contribute to the peripheral tolerance needed to remain in ...

Clinical Application of Sleeping Beauty and Artificial Antigen Presenting Cells to Genetically Modify T Cells from Peripheral and Umbilical Cord Blood

The potency of clinical-grade T cells can be improved by combining gene therapy with immunotherapy to engineer a biologic product with the potential for superior (i) recognition of tumor-associated antigens (TAAs), (ii) persistence after infusion, (iii) potential for migration to tumor sites, and (iv) ability to recycle effector functions within the tumor microenvironment. Most approaches to genetic manipulation of T cells engineered for human application have used retrovirus and lentivirus for the stable expression of CAR1-3. This approach, although compliant with current good manufacturing practice (GMP), can be expensive as it relies on the manufacture and release of clinical-grade recombinant virus from a limited number of production facilities. The electro-transfer of nonviral plasmids is an appealing alternative to transduction since DNA species can be produced to clinical grade at approximately 1/10th the cost of recombinant GMP-grade virus. To improve the efficiency of integration we adapted Sleeping Beauty (SB) transposon and transposase for human application4-8. Our SB system uses two DNA plasmids that consist of a transposon coding for a gene of interest (e.g. 2nd generation CD19-specific CAR transgene, designated CD19RCD28) and a transposase (e.g. SB11) which inserts the transgene into TA dinucleotide repeats9-11. To generate clinically-sufficient numbers of genetically modified T cells we use K562-derived artificial antigen presenting cells (aAPC) (clone #4) modified to express a TAA (e.g. CD19) as well as the T cell costimulatory molecules CD86, CD137L, a membrane-bound version of interleukin (IL)-15 (peptide fused to modified IgG4 Fc region) and CD64 (Fc-&gamma; receptor 1) for the loading of monoclonal antibodies (mAb)12. In this report, we demonstrate the procedures that can be undertaken in compliance with cGMP to generate CD19-specific CAR+ T cells suitable for human application. This was achieved by the synchronous electro-transfer of two DNA plasmids, a SB transposon (CD19RCD28) and a SB transposase (SB11) followed by retrieval of stable integrants by the every-7-day additions (stimulation cycle) of &gamma;-irradiated aAPC (clone #4) in the presence of soluble recombinant human IL-2 and IL-2113. Typically 4 cycles (28 days of continuous culture) are undertaken to generate clinically-appealing numbers of T cells that stably express the CAR. This methodology to manufacturing clinical-grade CD19-specific T cells can be applied to T cells derived from peripheral blood (PB) or umbilical cord blood (UCB). Furthermore, this approach can be harnessed to generate T cells to diverse tumor types by pairing the specificity of the introduced CAR with expression of the TAA, recognized by the CAR, on the aAPC.

Clinical Application of Sleeping Beauty and Artificial Antigen Presenting Cells to Genetically Modify T Cells from Peripheral and Umbilical Cord Blood

T cells expressing a CD19-specific chimeric antigen receptor (CAR) are infused as investigational treatment of B-cell malignancies in our first-in-human gene therapy trials. We describe genetic modification of T cells using the Sleeping Beauty (SB) system to introduce CD19-specific CAR and selective propagation on designer CD19+ artificial antigen presenting cells.

السريرية تطبيق<em&gt; الجمال النائم</em&gt; ومستضد تقديم الخلايا الاصطناعية لتعديل وراثيا خلايا T من دم الحبل السري والمحيطية

The potency of clinical-grade T cells can be improved by combining gene therapy with immunotherapy to engineer  a biologic product with the potential for ...

Generation of Human Monocyte-derived Dendritic Cells from Whole Blood

Dendritic cells (DCs) recognize foreign structures of different pathogens, such as viruses, bacteria, and fungi, via a variety of pattern recognition receptors (PRRs) expressed on their cell surface and thereby activate and regulate immunity. 
The major function of DCs is the induction of adaptive immunity in the lymph nodes by presenting antigens via MHC I and MHC II molecules to na&#239;ve T lymphocytes. Therefore, DCs have to migrate from the periphery to the lymph nodes after the recognition of pathogens at the sites of infection. For in vitro experiments or DC vaccination strategies, monocyte-derived DCs are routinely used. These cells show similarities in physiology, morphology, and function to conventional myeloid dendritic cells. They are generated by interleukin 4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation of monocytes isolated from healthy donors. Here, we demonstrate how monocytes are isolated and stimulated from anti-coagulated human blood after peripheral blood mononuclear cell (PBMC) enrichment by density gradient centrifugation. Human monocytes are differentiated into immature DCs and are ready for experimental procedures in a non-clinical setting after 5 days of incubation.

Here, we demonstrate how monocytes are isolated by magnetic bead separation from peripheral blood mononuclear cells after density gradient centrifugation of human anti-coagulated blood. Following incubation for 5 days, human monocytes are differentiated into immature dendritic cells and are ready for experimental procedures in a non-clinical setting.

جيل من الوحيدات المستمدة الخلايا الجذعية البشرية من الدم الكامل

Dendritic cells (DCs) recognize foreign structures of different pathogens, such as viruses, bacteria, and fungi, via a variety of pattern recognition ...

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.

جيل من التمييزية مونوكلونل البشرية من خلايا نادرة محددة مستضد ب المتداولة في الدم

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

Assessment of the Synaptic Interface of Primary Human T Cells from Peripheral Blood and Lymphoid Tissue

The current understanding of the dynamics and structural features of T-cell synaptic interfaces has been largely determined through the use of glass-supported planar bilayers and in vitro-derived T-cell clones or lines1,2,3,4. How these findings apply to the primary human T cells isolated from blood or lymphoid tissues is not known, partly due to significant difficulties in obtaining a sufficient number of cells for analysis5. Here we address this through the development of a technique exploiting multichannel flow slides to build planar lipid bilayers containing activating and adhesion molecules. The low height of the flow slides promotes rapid cell sedimentation in order to synchronize cell:bilayer attachment, thereby allowing researchers to study the dynamic of the synaptic interface formation and the kinetics of the granules release. We apply this approach to analyze the synaptic interface of as few as 104 to 105 primary cryopreserved T cells isolated from lymph nodes (LN) and peripheral blood (PB). The results reveal that the novel planar lipid bilayer technique enables the study of the biophysical properties of primary human T cells derived from blood and tissues in the context of health and disease.

The protocol describes a technique to study the ability of primary polyclonal human T cells to form synaptic interfaces using planar lipid bilayers. We use this technique to show the differential synapse formation capability of human primary T cells derived from lymph nodes and peripheral blood.

تقييم الواجهة متشابك لخلايا تي البشرية الأولية من الدم والأنسجة اللمفاوية

The current understanding of the dynamics and structural features of T-cell synaptic interfaces has been largely determined through the use of ...

Flotation-Based T Cell Isolation, Activation, and Expansion from Human Peripheral Blood Mononuclear Cell Samples Using Microbubbles

The process of isolating T cells from peripheral blood mononuclear&#160;cells (PBMCs) to establish ex vivo cultures is crucial for research, clinical testing, and cell-based therapies. In this study, a simple, novel protocol to isolate, activate, and expand T cells from PBMCs ex vivo is presented. This study utilizes functionalized buoyancy-activated cell sorting (BACS) technology to isolate and activate T cells. Briefly, the protocol involves the positive selection of CD3+ cells from leukopak-derived PBMCs, followed by a 48 h co-stimulation with pre-conjugated anti-CD28-bound streptavidin microbubbles (SAMBs) prior to transduction in 24-well plates. Functionalized microbubbles offer a unique opportunity to buoyantly activate cells, leading to proliferative phenotypes that allow for expansion with minimal exhaustion. This technique offers reduced exhaustion because the co-stimulatory microbubbles remain buoyant and return to the top of the culture medium, thus reducing the amount of time that the expanding cells are in contact with the co-stimulatory factors. The results indicate that the isolated and cultured T cells receive enough stimulation to activate and proliferate but not to an extent that leads to overactivation, which then leads to exhaustion, as demonstrated by the presence of excessive PD-1.

The objective of this study is to demonstrate the feasibility of flotation-based separation to isolate, activate, and expand primary human T cells.

عزل الخلايا التائية القائمة على التعويم وتنشيطها وتوسيعها من عينات خلايا الدم أحادية النواة المحيطية البشرية باستخدام الفقاعات الدقيقة

The process of isolating T cells from peripheral blood mononuclear&#160;cells (PBMCs) to establish ex vivo cultures is crucial for research, clinical ...

Differentiation of Functional Osteoclasts from Human Peripheral Blood CD14+ Monocytes

Osteoclasts (OCs) are bone-resorbing cells that play a pivotal role in skeletal development and adult bone remodeling. Several bone disorders are caused by increased differentiation and activation of OCs, so the inhibition of this pathobiology is a key therapeutic principle.Two key factors drive the differentiation of OCs from myeloid precursors: macrophage colony-stimulating factor (M-CSF) and receptor activator of nuclear factor kappa-B ligand (RANKL). Human circulating CD14+ monocytes have long been known to differentiate into OCs in vitro. However, the exposure time and the concentration of RANKL influence the differentiation efficiency. Indeed, protocols for the generation of human OCs in vitro have been described, but they often result in a poor and lengthy differentiation process. Herein, a robust and standardized protocol for generating functionally active mature human OCs in a timely manner is provided. CD14+ monocytes are enriched from human peripheral blood mononuclear cells (PBMCs) and primed with M-CSF to upregulate RANK. Subsequent exposure to RANKL generates OCs in a dose- and time-dependent manner. OCs are identified and quantified by staining with tartrate acid-resistant phosphatase (TRAP) and light microscopy analysis. Immunofluorescence staining of nuclei and F-actin is used to identify functionally active OCs. In addition, OSCAR+CD14&#8722; mature OCs are further enriched via flow cytometry cell sorting, and OC functionality quantified by mineral (or dentine/bone) resorption assays and actin ring formation. Finally, a known OC inhibitor, rotenone, is used on mature OCs, demonstrating that adenosine triphosphate (ATP) production is essential for actin ring integrity and OC function. In conclusion, a robust assay for differentiating high numbers of OCs is established in this work, which in combination with actin ring staining and an ATP assay&#160;provides a useful in vitro model to evaluate OC function and to screen for novel therapeutic compounds that can modulate the differentiation process.

Differentiation of Functional Osteoclasts from Human Peripheral Blood CD14+ Monocytes

Osteoclasts are key bone-resorbing cells in the body. This protocol describes a reliable method for the in vitro differentiation of osteoclasts from human peripheral blood monocytes. This method can be used as an important tool to further understand osteoclast biology in homeostasis and in diseases.

تمايز الخلايا العظمية الوظيفية من الخلايا الوحيدة CD14 + للدم المحيطي البشري

Osteoclasts (OCs) are bone-resorbing cells that play a pivotal role in skeletal development and adult bone remodeling. Several bone disorders are caused ...