The authors would like to thank Bethany Carboneau (Vanderbilt University) for critical reading of this manuscript. We also thank Anastasia Coldren (Vanderbilt University Medical Center Islet Procurement and Analysis Core) for islet isolations, and Dr. Alvin C. Powers (Vanderbilt University Medical Center) and Dr. David Jacobson (Vanderbilt University) for use of their centrifuge and tissue culture facility. This research involved use of the Islet Procurement and Analysis Core of the Vanderbilt Diabetes Research and Training Center supported by NIH grant DK20593. This work was supported by an American Heart Association Postdoctoral Fellowship (14POST20380262) to R.C.P., and grants from the Juvenile Diabetes Research Foundation (1-2011-592), and Department of Veterans Affairs (1BX00090-01A1) to M.A.G.

<ol>
	<li>Butler, A. E., 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=Beta-cell+deficit+and+increased+beta-cell+apoptosis+in+humans+with+type+2+diabetes.">Beta-cell deficit and increased beta-cell apoptosis in humans with type 2 diabetes.</a> Diabetes. 52 (1), 102-110 (2003).</li><li>Levy, J., Atkinson, A. B., Bell, P. M., McCance, D. R., Hadden, D. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Beta-cell+deterioration+determines+the+onset+and+rate+of+progression+of+secondary+dietary+failure+in+type+2+diabetes+mellitus:+the+10-year+follow-up+of+the+Belfast+Diet+Study.">Beta-cell deterioration determines the onset and rate of progression of secondary dietary failure in type 2 diabetes mellitus: the 10-year follow-up of the Belfast Diet Study.</a> Diabet Med. 15 (4), 290-296 (1998).</li><li>Bouwens, L., Rooman, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+pancreatic+beta-cell+mass.">Regulation of pancreatic beta-cell mass.</a> Physiol Rev. 85 (4), 1255-1270 (2005).</li><li>McCall, M., Shapiro, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Update+on+islet+transplantation.">Update on islet transplantation.</a> Cold Spring Harb Perspect Med. 2 (7), 007823 (2012).</li><li>Danhier, F., 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=PLGA-based+nanoparticles:+an+overview+of+biomedical+applications.">PLGA-based nanoparticles: an overview of biomedical applications.</a> J Control Release. 161 (2), 505-522 (2012).</li><li>Skelin, M., Rupnik, M., Cencic, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pancreatic+beta+cell+lines+and+their+applications+in+diabetes+mellitus+research.">Pancreatic beta cell lines and their applications in diabetes mellitus research.</a> ALTEX. 27 (2), 105-113 (2010).</li><li>Rui, 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=Controlled+release+of+vascular+endothelial+growth+factor+using+poly-lactic-co-glycolic+acid+microspheres:+in+vitro+characterization+and+application+in+polycaprolactone+fumarate+nerve+conduits.">Controlled release of vascular endothelial growth factor using poly-lactic-co-glycolic acid microspheres: in vitro characterization and application in polycaprolactone fumarate nerve conduits.</a> Acta Biomater. 8 (2), 511-518 (2012).</li><li>Lacy, P. E., Kostianovsky, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+for+the+isolation+of+intact+islets+of+Langerhans+from+the+rat+pancreas.">Method for the isolation of intact islets of Langerhans from the rat pancreas.</a> Diabetes. 16 (1), 35-39 (1967).</li><li>Szot, G. L., Koudria, P., Bluestone, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Murine+pancreatic+islet+isolation.">Murine pancreatic islet isolation.</a> J Vis Exp. (7), e255 (2007).</li><li>Mukherjee, B., Santra, K., Pattnaik, G., Ghosh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation,+characterization+and+in-vitro+evaluation+of+sustained+release+protein-loaded+nanoparticles+based+on+biodegradable+polymers.">Preparation, characterization and in-vitro evaluation of sustained release protein-loaded nanoparticles based on biodegradable polymers.</a> Int J Nanomedicine. 3 (4), 487-496 (2008).</li><li>Riley, K. G., 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=Connective+tissue+growth+factor+modulates+adult+beta-cell+maturity+and+proliferation+to+promote+beta-cell+regeneration+in+mice.">Connective tissue growth factor modulates adult beta-cell maturity and proliferation to promote beta-cell regeneration in mice.</a> Diabetes. 64 (4), 1284-1298 (2015).</li><li>Mosser, R. E., Gannon, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+assay+for+small+scale+screening+of+candidate+beta+cell+proliferative+factors+using+intact+islets.">An assay for small scale screening of candidate beta cell proliferative factors using intact islets.</a> Biotechniques. 55 (6), 310-312 (2013).</li><li>Carvell, M. J., Marsh, P. J., Persaud, S. J., Jones, 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=E-cadherin+interactions+regulate+beta-cell+proliferation+in+islet-like+structures.">E-cadherin interactions regulate beta-cell proliferation in islet-like structures.</a> Cell Physiol Biochem. 20 (5), 617-626 (2007).</li><li>Wakae-Takada, N., Xuan, S., Watanabe, K., Meda, P., Leibel, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Molecular+basis+for+the+regulation+of+islet+beta+cell+mass+in+mice:+the+role+of+E-cadherin.">Molecular basis for the regulation of islet beta cell mass in mice: the role of E-cadherin.</a> Diabetologia. 56 (4), 856-866 (2013).</li><li>Gavrieli, Y., Sherman, Y., Ben-Sasson, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+programmed+cell+death+in+situ+via+specific+labeling+of+nuclear+DNA+fragmentation.">Identification of programmed cell death in situ via specific labeling of nuclear DNA fragmentation.</a> J Cell Biol. 119 (3), 493-501 (1992).</li><li>Kuo, L. J., Yang, L. X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gamma-H2AX+-+a+novel+biomarker+for+DNA+double-strand+breaks.">Gamma-H2AX - a novel biomarker for DNA double-strand breaks.</a> In Vivo. 22 (3), 305-309 (2008).</li><li>Daoud, J., Rosenberg, L., Tabrizian, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pancreatic+islet+culture+and+preservation+strategies:+advances,+challenges,+and+future+outlook.">Pancreatic islet culture and preservation strategies: advances, challenges, and future outlook.</a> Cell Transplant. 19 (12), 1523-1535 (2010).</li><li>Carter, J. D., Dula, S. B., Corbin, K. L., Wu, R., Nunemaker, C. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+guide+to+rodent+islet+isolation+and+assessment.">A practical guide to rodent islet isolation and assessment.</a> Biol Proced Online. 11, 3-31 (2009).</li><li>Xu, Q., He, C., Xiao, C., Chen, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reactive+Oxygen+Species+(ROS)+Responsive+Polymers+for+Biomedical+Applications.">Reactive Oxygen Species (ROS) Responsive Polymers for Biomedical Applications.</a> Macromol Biosci. 16 (5), 635-646 (2016).</li><li>Makadia, H. K., Siegel, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Poly+Lactic-co-Glycolic+Acid+(PLGA)+as+Biodegradable+Controlled+Drug+Delivery+Carrier.">Poly Lactic-co-Glycolic Acid (PLGA) as Biodegradable Controlled Drug Delivery Carrier.</a> Polymers (Basel). 3 (3), 1377-1397 (2011).</li><li>Cui, F., Shi, K., Zhang, L., Tao, A., Kawashima, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biodegradable+nanoparticles+loaded+with+insulin-phospholipid+complex+for+oral+delivery:+preparation,+in+vitro+characterization+and+in+vivo+evaluation.">Biodegradable nanoparticles loaded with insulin-phospholipid complex for oral delivery: preparation, in vitro characterization and in vivo evaluation.</a> J Control Release. 114 (2), 242-250 (2006).</li><li>Kavanaugh, T. E., Werfel, T. A., Cho, H., Hasty, K. A., Duvall, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Particle-based+technologies+for+osteoarthritis+detection+and+therapy.">Particle-based technologies for osteoarthritis detection and therapy.</a> Drug Deliv Transl Res. , (2015).</li><li>Joshi, R. V., Nelson, C. E., Poole, K. M., Skala, M. C., Duvall, C. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dual+pH-+and+temperature-responsive+microparticles+for+protein+delivery+to+ischemic+tissues.">Dual pH- and temperature-responsive microparticles for protein delivery to ischemic tissues.</a> Acta Biomater. 9 (5), 6526-6534 (2013).</li><li>Poole, K. 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=ROS-responsive+microspheres+for+on+demand+antioxidant+therapy+in+a+model+of+diabetic+peripheral+arterial+disease.">ROS-responsive microspheres for on demand antioxidant therapy in a model of diabetic peripheral arterial disease.</a> Biomaterials. 41, 166-175 (2015).</li></ol>

The authors have nothing to disclose.

המחקר של התפשטות β-cell בתרבות נפגע בדרך כלל על ידי מספר קשיים. ראשית, קווי β-cell הנציח מאופיינים לתארים גבוהים של התפשטות ממה נמצא β-תאי אנדוגני איים חי. בנוסף, שורות התאים הנציחו אלה חסרות את הארכיטקטורה הנורמלית חיונית לתפקוד β-תא נורמלי. שתי עובדות אלו מקשות על מנת לקב...

β-תאי לבלב הם התאים היחידים המייצר אינסולין בגוף הם קריטיים לשמור על הומאוסטזיס הגלוקוז בדם. בעוד אנשים בריאים הם בעלי מסת β-cell מספיק ולתפקד להסדיר דם גלוקוז כראוי, אנשים עם סוכרת מתאפיינים המוני β-cell מספיק ו / או פונקציה 1,2. הוצע כי גרימת התפשטות β-cell יכול בסופו של דבר להגדיל β-cell המוני ולשחזר הומאוסטזיס הגלוקוז בחולי סוכרת 3. עם זאת, הערכה ואימות של תרכובות שגשוג פוטנציאל β-תא איי שלמים הכרחי לפני ניתן לפתח טיפולים יעילים. השתלת איי אדם cadaveric לתוך אנשים עם סוכרת משחזר הומאוסטזיס הגלוקוז בדם במשך זמן מה, אבל זמינויות ההצלחה של הליך ניסיוני זה הפריעו מחסור איי אדם זמינים להשתלה ועל ידי מוות בטא תא ומאחור האייםאה השתלת 4. אפילו עם גילוי הגורמים לגרום הכפל של תאים מייצרי אינסולין, אתגר גדול עדיין קיים במתן הגורמים הללו לאתרים רלוונטיים in vivo. אסטרטגיה אחת למסירה מקומית מתמשכת של תרכובות שגשוג β-cell היא פולי (לקטית-שיתוף גליקולית) חומצה (PLGA). יש PLGA היסטוריה של שימוש ב FDA אישר מוצרים משלוח סמים בשל בטיחות גבוהה, פריקות ביולוגית, קינטיקה שחרור המורחבת 5. באופן ספציפי, PLGA הוא קופולימר של lactide ו glycolide הזה מבזה באמצעות הידרוליזה עם מים או in vivo או בתרבות לחומצה לקטית וחומצה גליקולית, אשר מתרחשים מטבוליטים באופן טבעי בגוף. מתחם התרופה הכמוס יכול להשתחרר הסביבה על ידי שתי דיפוזיה ו / או מנגנוני שחרור מבוקר שפלים. Encapsulation של COI מספק הגנה מפני השפלה אנזימטי, שיפור הזמינות הביולוגית של מגיב לעומת unencapsulaטד COI 5. אנו ממליצים microspheres PLGA ניתן להשתמש כדי לנהל תרכובות המועמד איים שלמים בתרבות, ובסופו של דבר in vivo. בדיקת יעילותם של PLGA לנהל mitogens β-cell כדי איי vivo לשעבר היא קריטית לפני פרוטוקולי השתלת נחקרות. נכון לעכשיו, אין טכניקה למדוד התפשטות β-cell בבעלי חיים. ניסויים להעריך את האפקטיביות של תרכובות שגשוג פוטנציאל in vivo ולכן יש לתת לכלב של תרכובות אלה לחיות חיים, עם דיסקציה עוקבות ועיבוד של pancreata עבור immunolabeling. פרוטוקולים כאלה הם יקרים ומייגעים, ודורשים המתחם להיות מערכתיים, ללא כל ערובה לכך שהם יגיעו האי. לעומת זאת, כמה הנציח קווי β-cell זמינים לחקר תאים מייצרי אינסולין בתרבות, אבל שורות תאים אלה חסרים את הארכיטקטורה איון environment נמצא אורגניזמים חיים 6. קווי β-cell הונצח גם מאופיינים כבעלי מידה רבה יותר של שכפול מ β-תאי אנדוגני in vivo, ובכך סיבכה ניתוח של תרכובות המשרים התפשטות. במחקר זה, אנו מתארים פרוטוקול המשתמשת איים שלמים מבודדים עכברים בוגרים. בניגוד קווי β-cell, איים שלמים שומרים על ארכיטקטורת איון נורמלית. כמו כן, בניגוד הניסויים שנערכו in vivo, מתן תרכובות שגשוג ישירות איים שלמים תרבותיים מפחית באופן משמעותי את כמות ריאגנטים כי יש צורך למדוד במדויק התפשטות β-cell. המחקר הנוכחי מנצל PLGA כדי לנהל COI, בדוגמה זו, גורם הגדילה רקמת חיבור אנושי רקומביננטי (rhCTGF). השיטה המתוארת כאן מקנה יתרון משמעותי על פני הממשל של מתחם גלם האי בתרבית שכן היא מאפשרת שחרור מתמשך של מתחם לתוך התקשורת דואר. יש לציין, assay זה יכול להיות שונה כדי לנהל מגוון רחב של חלבונים ונוגדנים מעניינים איים שלמים. השפעות על סוגי תאים אנדוקריניות אחרות, כולל תאי α, ניתן לנתח גם.

<table border="0" cellpadding="0" cellspacing="0" width="819">
	<tbody>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Oregon Green 488 Carboxylic Acid, Succinimidyl Ester, 6-isomer</td>
			<td style="width:179px;">ThermoFisher Scientific</td>
			<td style="width:119px;">O6149</td>
			<td style="width:307px;">For labeling COI with fluorophore</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">DMSO Dimethyl Sulfoxide</td>
			<td style="width:179px;">Fisher BioReagents</td>
			<td style="width:119px;">BP231-1</td>
			<td>For dissolving fluorophore in step 1</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Disposable PD-10 Desalting Columns</td>
			<td style="width:179px;">GE Healthcare</td>
			<td style="width:119px;">17-0851-01</td>
			<td>Desalting column used in step 1</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:216px;">Resomer RG 505, Poly(D,L-lactide-co-glycolide), ester terminated, molecular weight 54,000-69,000</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">739960</td>
			<td>Used in generation of microspheres in step 2</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Poly(vinyl alcohol) molecular weight 89,000-98,000</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td align="right" style="width:119px;">341584</td>
			<td>Used in generation of microspheres in step 2</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">RPMI 1640</td>
			<td style="width:179px;">Thermo Scientific</td>
			<td style="width:119px;">11879-020</td>
			<td>For culturing islets</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Dextrose Anhydrous</td>
			<td style="width:179px;">Fisher BioReagents</td>
			<td style="width:119px;">200-075-1</td>
			<td>Supplement for islet media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Penicillin-Streptomycin</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:119px;">P4333</td>
			<td>Antibiotics for islet media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Normal horse serum</td>
			<td style="width:179px;">Jackson ImmunoResearch</td>
			<td style="width:119px;">008-000-121</td>
			<td>Supplement for islet media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">96-well tissue culture plate</td>
			<td style="width:179px;">Corning</td>
			<td align="right" style="width:119px;">3603</td>
			<td>For culturing islets</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">Ethylene glyco-bis(2-aminoethylether)-N,N,N&#39;,N&#39;-tetraacetic acid</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:119px;">E4378</td>
			<td>Supplement for pre-assay islet media</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Cytospin 4 Cytocentrifuge</td>
			<td style="width:179px;">Thermo Scientific</td>
			<td style="width:119px;">A78300003</td>
			<td>For spinning cells onto microscope slides</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">EZ Single Cytofunnel</td>
			<td style="width:179px;">Thermo Scientific</td>
			<td style="width:119px;">A78710020</td>
			<td>For spinning cells onto microscope slides</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Ethylenediaminetetraacetic acid</td>
			<td style="width:179px;">Fisher BioReagents</td>
			<td>BP118-500</td>
			<td>Used in dissociating islets</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">paraformaldehyde</td>
			<td style="width:179px;">Sigma-Aldrich</td>
			<td style="width:119px;">P6148</td>
			<td>For fixing cells</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Triton&#160; X-100</td>
			<td style="width:179px;">Fisher BioReagents</td>
			<td style="width:119px;">BP151</td>
			<td>For permeabilizing cells</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Normal donkey serum</td>
			<td style="width:179px;">Jackson ImmunoResearch</td>
			<td style="width:119px;">017-000-121</td>
			<td>Blocking reagents for immunofluorescence</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Anti-Ki67 antibody</td>
			<td style="width:179px;">abcam</td>
			<td style="width:119px;">ab15580</td>
			<td>For Ki67 immunofluorescence</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Polyclonal Guinea Pig Anti-Insulin</td>
			<td style="width:179px;">Dako</td>
			<td style="width:119px;">A0564</td>
			<td>For insulin immunofluorescence</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cy3 AffiniPure Donkey Anti-Rabbit</td>
			<td style="width:179px;">Jackson ImmunoResearch</td>
			<td style="width:119px;">711-165-152</td>
			<td>For Ki67 immunofluorescence</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cy5 AffiniPure Donkey Anti-Guinea Pig</td>
			<td style="width:179px;">Jackson ImmunoResearch</td>
			<td style="width:119px;">706-175-148</td>
			<td>For insulin immunofluorescence</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">DAPI (4&#39;,6-Diamidino-2-Phenylindole, Dihydrochloride)</td>
			<td style="width:179px;">ThermoFisher Scientific</td>
			<td style="width:119px;">D1306</td>
			<td>For nuclei visualization in immunofluorescence</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Aqua-Mount</td>
			<td style="width:179px;">Lerner Laboratories</td>
			<td align="right" style="width:119px;">13800</td>
			<td>Fast drying mounting media</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:216px;">FreeZone -105&#176;C 4.5 Liter Cascade Benchtop Freeze Dry System</td>
			<td style="width:179px;">Labconco</td>
			<td align="right" style="width:119px;">7382020</td>
			<td>For lyophilization of microspheres</td>
		</tr>
	</tbody>
</table>

sustained administration of &#946;-cell mitogens to intact mouse islets ex vivo using biodegradable poly(lactic-co-glycolic acid) microspheres

פיתוח חומרים ביולוגיים גדל באופן משמעותי את פוטנציאל שיגור תרופות למגוון של סוגי תאים ורקמות, כולל β-תאי הלבלב. בנוסף, חלקיקים ביולוגיים, הידרוג, ופיגומים גם מספקים הזדמנות ייחודית לניהול מתמשך, משלוח סמים לשליטה על בטא תאים בתרבית ו במודלי רקמה מושתלות. טכנולוגיות אלו מאפשרות בחקר גורמי התפשטות β-cell המועמד באמצעות איי שלמים ומערכת רלוונטית translationally. יתר על כן, בקביעה האפקטיבית ואת הכדאיות של גורמי מועמד בהמרצת ההתרבות β-cell במערכת תרבות היא קריטית לפני לנוע קדימה מודלי in vivo. בזאת, אנו מתארים שיטת שיתוף תרבות איי עכבר שלמים עם מתחם מתכלה של עניין (COI) פולי -loaded (לקטית-שיתוף גליקולית וחומצה) (PLGA) microspheres לצורך הערכת ההשפעות של שנגרם o שחרור באתרוגורמים mitogenic f על התפשטות β-cell. טכניקה זו מתארת ​​בפירוט כיצד ליצור microspheres PLGA המכיל מטען רצוי באמצעות ריאגנטים זמינים מסחרי. בעוד הטכניקה המתוארת משתמשת גורם הגדילה רקמת החיבור אנושי רקומביננטי (rhCTGF) כדוגמה, מגוון רחב של COI יכול לשמש בקלות. בנוסף, שיטה זו מנצלת 96-גם צלחות כדי למזער את כמות ריאגנטים צורך להעריך התפשטות β-cell. פרוטוקול זה ניתן להתאים בקלות כדי להשתמש בביו-חומרים אלטרנטיביים אופייני תא אנדוקריניות אחרות כגון הישרדות תא ומצב בידול.

איור 1 הוא ייצוג חזותי של microspheres שנוצר באמצעות פרוטוקול לעיל. הפרוטוקול המתואר כאן תשואות microspheres הטעון rhCTGF בגדלים שונים. השבר הגדול של microspheres יהיה בין 1 ל -10 מיקרומטר קוטר, אם כי microspheres מסוים עשוי להיות גדול יותר (איור 2). אם ?...

Watch this Scientific Journal Video about Sustained Administration of ÃŽÂ²-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Polylactic-co-glycolic acid Microspheres at JoVE.com

Sustained Administration of &#946;-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Poly(lactic-co-glycolic acid) Microspheres

Here, we present methodology to generate and administer compound of interest-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres to intact mouse islets in culture with subsequent immunofluorescence analysis of &#946;-cell proliferation. This method is suitable for determining the efficacy of candidate &#946;-cell mitogens.

מנהל מתמשך של mitogens β-cell כדי איי עכבר Intact<em&gt; Ex Vivo</em&gt; שימוש פוליפוני מתכלה (לקטית-שיתוף גליקולית וחומצה) מיקרוסכמות

The development of biomaterials has significantly increased the potential for targeted drug delivery to a variety of cell and tissue types, including the ...

sustained-administration-cell-mitogens-to-intact-mouse-islets-ex-vivo

Research

JoVE Journal

Bioengineering

7.2K Views.  Vanderbilt University Medical Center. Here, we present methodology to generate and administer compound of interest-loaded poly(lactic-co-glycolic acid) (PLGA) microspheres to intact mouse islets in culture with subsequent immunofluorescence analysis of β-cell proliferation. This method is suitable for determining the efficacy of candidate β-cell mitogens.

Video: Sustained Administration of β-cell Mitogens to Intact Mouse Islets Ex Vivo Using Biodegradable Poly(lactic-co-glycolic acid) Microspheres

High Resolution 3D Imaging of Ex-Vivo Biological Samples by Micro CT

Non-destructive volume visualization can be achieved only by tomographic techniques, of which the most efficient is the x-ray micro computerized tomography (&mu;CT).
High resolution &mu;CT is a very versatile yet accurate (1-2 microns of resolution) technique for 3D examination of ex-vivo biological samples1, 2. As opposed to electron tomography, the &mu;CT allows the examination of up to 4 cm thick samples. This technique requires only few hours of measurement as compared to weeks in histology. In addition, &mu;CT does not rely on 2D stereologic models, thus it may complement and in some cases can even replace histological methods3, 4, which are both time consuming and destructive. Sample conditioning and positioning in &mu;CT is straightforward and does not require high vacuum or low temperatures, which may adversely affect the structure. The sample is positioned and rotated 180&deg; or 360&deg;between a microfocused x-ray source and a detector, which includes a scintillator and an accurate CCD camera, For each angle a 2D image is taken, and then the entire volume is reconstructed using one of the different available algorithms5-7. The 3D resolution increases with the decrease of the rotation step. The present video protocol shows the main steps in preparation, immobilization and positioning of the sample followed by imaging at high resolution.

High Resolution 3D Imaging of Ex-Vivo Biological Samples by Micro CT

Non-destructive volume visualization can be achieved only by tomographic techniques, of which the most efficient is the x-ray micro computerized tomography ( CT).

ברזולוציה גבוהה 3D הדמיה של Ex-Vivo דגימות ביולוגיות באמצעות מיקרו-CT

Non-destructive volume visualization can be achieved only by tomographic techniques, of which the most efficient is the x-ray micro computerized ...

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage1-3. Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease4. 
The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve5. Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves6-9. Pulsatile bioreactors have also been developed to study a range of tissues including cartilage10, bone11 and bladder12. The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. 
The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment.

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

A cyclic pressure bioreactor capable of subjecting heart valve tissue to physiological and pathological pressure conditions has been designed. A LabVIEW program allows users to control pressure magnitude, amplitude and frequency. This device can be used to study the mechanobiology of heart valve tissue or isolated cells.

עיצוב של bioreactor לחץ על מחזורי Ex Vivo מחקר של מסתמי הלב אבי העורקים

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic ...

Ex vivo Mimicry of Normal and Abnormal Human Hematopoiesis

Hematopoietic stem cells require a unique microenvironment in order to sustain blood cell formation1; the bone marrow (BM) is a complex three-dimensional (3D) tissue wherein hematopoiesis is regulated by spatially organized cellular microenvironments termed niches2-4. The organization of the BM niches is critical for the function or dysfunction of normal or malignant BM5. Therefore a better understanding of the in vivo microenvironment using an ex vivo mimicry would help us elucidate the molecular, cellular and microenvironmental determinants of leukemogenesis6.
Currently, hematopoietic cells are cultured in vitro in two-dimensional (2D) tissue culture flasks/well-plates7 requiring either co-culture with allogenic or xenogenic stromal cells or addition of exogenous cytokines8. These conditions are artificial and differ from the in vivo microenvironment in that they lack the 3D cellular niches and expose the cells to abnormally high cytokine concentrations which can result in differentiation and loss of pluripotency9,10.
Herein, we present a novel 3D bone marrow culture system that simulates the in vivo 3D growth environment and supports multilineage hematopoiesis in the absence of exogenous growth factors. The highly porous scaffold used in this system made of polyurethane (PU), facilitates high-density cell growth across a higher specific surface area than the conventional monolayer culture in 2D11. Our work has indicated that this model supported the growth of human cord blood (CB) mononuclear cells (MNC)12 and primary leukemic cells in the absence of exogenous cytokines. This novel 3D mimicry provides a viable platform for the development of a human experimental model to study hematopoiesis and to explore novel treatments for leukemia.

Ex vivo Mimicry of Normal and Abnormal Human Hematopoiesis

A 3D culture system for hematopoiesis is described using human cord blood and leukemic bone marrow cells. The method is based on the use of a porous synthetic polyurethane scaffold coated with extracellular matrix proteins. This scaffold is adaptable to accommodate a wide range of cells.

Ex vivo החקיינות של hematopoiesis אנושיים בריאים חריגה

Hematopoietic stem cells require a unique microenvironment in order to sustain blood cell formation1; the bone marrow (BM) is a complex three-dimensional ...

Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting airways, whereas adenocarcinomas are typically more peripheral in location. Lung malignancy detection early in the disease process may be difficult due to several limitations: radiological resolution, bronchoscopic limitations in evaluating tissue underlying the airway mucosa and identifying early pathologic changes, and small sample size and/or incomplete sampling in histology biopsies. High resolution imaging modalities, such as optical frequency domain imaging (OFDI), provide non-destructive, large area 3-dimensional views of tissue microstructure to depths approaching 2 mm in real time (Figure 1)2-6. OFDI has been utilized in a variety of applications, including evaluation of coronary artery atherosclerosis6,7 and esophageal intestinal metaplasia and dysplasia6,8-10.
Bronchoscopic OCT/OFDI has been demonstrated as a safe in vivo imaging tool for evaluating the pulmonary airways11-23 (Animation). OCT has been assessed in pulmonary airways16,23 and parenchyma17,22 of animal models and in vivo human airway14,15. OCT imaging of normal airway has demonstrated visualization of airway layering and alveolar attachments, and evaluation of dysplastic lesions has been found useful in distinguishing grades of dysplasia in the bronchial mucosa11,12,20,21. OFDI imaging of bronchial mucosa has been demonstrated in a short bronchial segment (0.8 cm)18. Additionally, volumetric OFDI spanning multiple airway generations in swine and human pulmonary airways in vivo has been described19. Endobronchial OCT/OFDI is typically performed using thin, flexible catheters, which are compatible with standard bronchoscopic access ports. Additionally, OCT and OFDI needle-based probes have recently been developed, which may be used to image regions of the lung beyond the airway wall or pleural surface17.
While OCT/OFDI has been utilized and demonstrated as feasible for in vivo pulmonary imaging, no studies with precisely matched one-to-one OFDI:histology have been performed. Therefore, specific imaging criteria for various pulmonary pathologies have yet to be developed. Histopathological counterparts obtained in vivo consist of only small biopsy fragments, which are difficult to correlate with large OFDI datasets. Additionally, they do not provide the comprehensive histology needed for registration with large volume OFDI. As a result, specific imaging features of pulmonary pathology cannot be developed in the in vivo setting. Precisely matched, one-to-one OFDI and histology correlation is vital to accurately evaluate features seen in OFDI against histology as a gold standard in order to derive specific image interpretation criteria for pulmonary neoplasms and other pulmonary pathologies. Once specific imaging criteria have been developed and validated ex vivo with matched one-to-one histology, the criteria may then be applied to in vivo imaging studies. Here, we present a method for precise, one to one correlation between high resolution optical imaging and histology in ex vivo lung resection specimens. Throughout this manuscript, we describe the techniques used to match OFDI images to histology. However, this method is not specific to OFDI and can be used to obtain histology-registered images for any optical imaging technique. We performed airway centered OFDI with a specialized custom built bronchoscopic 2.4 French (0.8 mm diameter) catheter. Tissue samples were marked with tissue dye, visible in both OFDI and histology. Careful orientation procedures were used to precisely correlate imaging and histological sampling locations. The techniques outlined in this manuscript were used to conduct the first demonstration of volumetric OFDI with precise correlation to tissue-based diagnosis for evaluating pulmonary pathology24. This straightforward, effective technique may be extended to other tissue types to provide precise imaging to histology correlation needed to determine fine imaging features of both normal and diseased tissues.

Optical Frequency Domain Imaging of Ex vivo Pulmonary Resection Specimens: Obtaining One to One Image to Histopathology Correlation

A method to image ex vivo pulmonary resection specimens with optical frequency domain imaging (OFDI) and obtain precise correlation to histology is described, which is essential to developing specific OFDI interpretation criteria for pulmonary pathology. This method is applicable to other tissue types and imaging techniques to obtain precise imaging to histology correlation for accurate image interpretation and assessment. Imaging criteria established with this technique would then be applicable to image assessment in future in vivo studies.

הדמיה אופטית של תחום תדר<em&gt; גופיים</em&gt; דוגמאות כריתת ריאה: קבלת תמונה אחד לאחד למתאם היסטופתולוגיה

Lung cancer is the leading cause of cancer-related deaths1. Squamous cell and small cell cancers typically arise in association with the conducting ...

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced birth defects and many later studies afterwards proved the opposite. Today several harmful xenobiotics like nicotine, heroin, methadone or drugs as well as environmental pollutants were described to overcome this barrier. With the growing use of nanotechnology, the placenta is likely to come into contact with novel nanoparticles either accidentally through exposure or intentionally in the case of potential nanomedical applications. Data from animal experiments cannot be extrapolated to humans because the placenta is the most species-specific mammalian organ 1. Therefore, the ex vivo dual recirculating human placental perfusion, developed by Panigel et al. in 1967 2 and continuously modified by Schneider et al. in 1972 3, can serve as an excellent model to study the transfer of xenobiotics or particles.
Here, we focus on the ex vivo dual recirculating human placental perfusion protocol and its further development to acquire reproducible results.
The placentae were obtained after informed consent of the mothers from uncomplicated term pregnancies undergoing caesarean delivery. The fetal and maternal vessels of an intact cotyledon were cannulated and perfused at least for five hours. As a model particle fluorescently labelled polystyrene particles with sizes of 80 and 500 nm in diameter were added to the maternal circuit. The 80 nm particles were able to cross the placental barrier and provide a perfect example for a substance which is transferred across the placenta to the fetus while the 500 nm particles were retained in the placental tissue or maternal circuit. The ex vivo human placental perfusion model is one of few models providing reliable information about the transport behavior of xenobiotics at an important tissue barrier which delivers predictive and clinical relevant data.

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model

The ex vivo dual recirculating human placental perfusion model can be used to investigate the transfer of xenobiotics and nanoparticles across the human placenta. In this video protocol we describe the equipment and techniques required for a successful execution of a placenta perfusion.

קביעת תעריף הובלת xenobiotics ו ננו מעבר לשליה באמצעות<em&gt; לשעבר vivo</em&gt; דגם זלוף שליה אנושי

Decades ago the human placenta was thought to be an impenetrable barrier between mother and unborn child. However, the discovery of thalidomide-induced ...

Programming Stem Cells for Therapeutic Angiogenesis Using Biodegradable Polymeric Nanoparticles

Controlled vascular growth is critical for successful tissue regeneration and wound healing, as well as for treating ischemic diseases such as stroke, heart attack or peripheral arterial diseases. Direct delivery of angiogenic growth factors has the potential to stimulate new blood vessel growth, but is often associated with limitations such as lack of targeting and short half-life in vivo. Gene therapy offers an alternative approach by delivering genes encoding angiogenic factors, but often requires using virus, and is limited by safety concerns. Here we describe a recently developed strategy for stimulating vascular growth by programming stem cells to overexpress angiogenic factors in situ using biodegradable polymeric nanoparticles. Specifically our strategy utilized stem cells as delivery vehicles by taking advantage of their ability to migrate toward ischemic tissues in vivo. Using the optimized polymeric vectors, adipose-derived stem cells were modified to overexpress an angiogenic gene encoding vascular endothelial growth factor (VEGF). We described the processes for polymer synthesis, nanoparticle formation, transfecting stem cells in vitro, as well as methods for validating the efficacy of VEGF-expressing stem cells for promoting angiogenesis in a murine hindlimb ischemia model.

We describe the method of programming stem cells to overexpress therapeutic factors for angiogenesis using biodegradable polymeric nanoparticles. Processes described include polymer synthesis, transfecting adipose-derived stem cells in vitro, and validating the efficacy of programmed stem cells to promote angiogenesis in a murine hindlimb ischemia model.

תאי גזע תכנות טיפולי אנגיוגנזה שימוש אורגניים פולימריים חלקיקים

Controlled vascular growth is critical for successful tissue regeneration and wound healing, as well as for treating ischemic diseases such as stroke, ...

Intra-lymph Node Injection of Biodegradable Polymer Particles

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these foreign molecules to T and B lymphocytes. Lymph nodes have thus become critical targets for new vaccines and immunotherapies. A recent strategy for targeting these tissues is direct lymph node injection of soluble vaccine components, and clinical trials involving this technique have been promising. Several biomaterial strategies have also been investigated to improve lymph node targeting, for example, tuning particle size for optimal drainage of biomaterial vaccine particles. In this paper we present a new method that combines direct lymph node injection with biodegradable polymer particles that can be laden with antigen, adjuvant, or other vaccine components. In this method polymeric microparticles or nanoparticles are synthesized by a modified double emulsion protocol incorporating lipid stabilizers. Particle properties (e.g.&#160;size, cargo loading) are confirmed by laser diffraction and fluorescent microscopy, respectively. Mouse lymph nodes are then identified by peripheral injection of a nontoxic tracer dye that allows visualization of the target injection site and subsequent deposition of polymer particles in lymph nodes. This technique allows direct control over the doses and combinations of biomaterials and vaccine components delivered to lymph nodes and could be harnessed in the development of new biomaterial-based vaccines.

Lymph nodes are the immunological tissues that orchestrate immune response and are a critical target for vaccines. Biomaterials have been employed to better target lymph nodes and to control delivery of antigens or adjuvants. This paper describes a technique combining these ideas to inject biocompatible polymer particles into lymph nodes.

הזרקת בלוטות תוך-לימפתיות של חלקיקי פולימר מתכלים

Generation of adaptive immune response relies on efficient drainage or trafficking of antigen to lymph nodes for processing and presentation of these ...

The Use of the Ex Vivo Chandler Loop Apparatus to Assess the Biocompatibility of Modified Polymeric Blood Conduits

The foreign body reaction occurs when a synthetic surface is introduced to the body. It is characterized by adsorption of blood proteins and the subsequent attachment and activation of platelets, monocyte/macrophage adhesion, and inflammatory cell signaling events, leading to post-procedural complications. The Chandler Loop Apparatus is an experimental system that allows researchers to study the molecular and cellular interactions that occur when large volumes of blood are perfused over polymeric conduits. To that end, this apparatus has been used as an ex vivo model allowing the assessment of the anti-inflammatory properties of various polymer surface modifications. Our laboratory has shown that blood conduits, covalently modified via photoactivation chemistry with recombinant CD47, can confer biocompatibility to polymeric surfaces. Appending CD47 to polymeric surfaces could be an effective means to promote the efficacy of polymeric blood conduits. Herein is the methodology detailing the photoactivation chemistry used to append recombinant CD47 to clinically relevant polymeric blood conduits and the use of the Chandler Loop as an ex vivo experimental model to examine blood interactions with the CD47 modified and control conduits.

The Use of the Ex Vivo Chandler Loop Apparatus to Assess the Biocompatibility of Modified Polymeric Blood Conduits

Blood exposure to polymeric blood conduits initiates the foreign body reaction that has been implicated in clinical complications. Here, the Chandler Loop Apparatus, an experimental tool mimicking blood perfusion through these conduits, is described. Appendage of recombinant CD47 results in decreased evidence of the foreign body reaction on these conduits.

השימוש ב<em&gt; Ex Vivo</em&gt; מכשירי צ&#39;נדלר Loop להערכת Biocompatibility של צינורות דם פולימרית השתנה

The foreign body reaction occurs when a synthetic surface is introduced to the body. It is characterized by adsorption of blood proteins and the ...

Primary Clarification of CHO Harvested Cell Culture Fluid using an Acoustic Separator

Primary clarification is an essential step in a biomanufacturing process for the initial removal of cells from therapeutic products within the harvested cell culture fluid. While traditional methods like centrifugation or filtration are widely implemented for cell removal, the equipment for these processes have large footprints and operation can involve contamination risks and filter fouling. Additionally, traditional methods may not be ideal for continuous bioprocessing schemes for primary clarification. Thus, an alternate application using acoustic (sound) waves was investigated to continuously separate cells from the cell culture fluid. Presented in this study is a detailed protocol for using a bench-scale acoustic wave separator (AWS) for the primary separation of culture fluid containing a monoclonal IgG1 antibody from a CHO cell bioreactor harvest. Representative data are presented from the AWS and demonstrate how to achieve effective cell clarification and product recovery. Finally, potential applications for AWS in continuous bioprocessing are discussed. Overall, this study provides a practical and general protocol for the implementation of AWS in primary clarification for CHO cell cultures and further describes its application potential in continuous bioprocessing.

Presented here is a protocol for the primary clarification of CHO cell culture using an acoustic separator. This protocol can be used for the primary clarification of shake flask cultures or bioreactor harvests and has the potential application for continuous clarification of the cell bleed material during perfusion bioreactor operations.

הבהרה ראשונית של נוזל תרבית תאים שנקטפו על ידי CHO באמצעות מפריד אקוסטי

Primary clarification is an essential step in a biomanufacturing process for the initial removal of cells from therapeutic products within the harvested ...

Preparation, Administration, and Assessment of In Vivo Tissue-Specific Cellular Uptake of Fluorescent Dye-Labeled Liposomes

There is a growing interest in using liposomes to deliver compounds in vivo particularly for targeted treatment approaches. Depending on the liposome formulation, liposomes may be preferentially taken up by different cell types in the body. This may influence the efficacy of the therapeutic particle as progression of different diseases is tissue- and cell-type-specific. In this protocol, we present one method for synthesizing and fluorescently labeling liposomes using DSPC, cholesterol, and PEG-2000 DSPE and the lipid dye DiD as a fluorescent label. This protocol also presents an approach for delivering liposomes in vivo and assessing cell-specific uptake of liposomes using flow cytometry. This approach can be used to determine the types of cells that take up liposomes and quantify the distribution and proportion of liposome-uptake across cell types and tissues. While not mentioned in this protocol, additional assays such as immunofluorescence and single-cell fluorescence imaging on a cytometer will strengthen any findings or conclusions made as they permit assessment of intracellular staining. Protocols may also need to be adapted depending on the tissue(s) of interest.

The goal of this protocol is to synthesize fluorescently-labeled liposomes and use flow cytometry to identify in vivo localization of liposomes at a cellular level.

הכנה, מתן והערכה של ספיגה תאית ספציפית לרקמת in vivo של ליפוזומים בעלי תווית צבע פלואורסצנטי

There is a growing interest in using liposomes to deliver compounds in vivo particularly for targeted treatment approaches. Depending on the liposome ...