Name: wet-spinning-based molding process of gelatin for tissue regeneration
Uploaded: 2019-03-07T14:15:00
Description: Watch this Scientific Journal Video about Wet-spinning-based Molding Process of Gelatin for Tissue Regeneration at JoVE.com

Denne undersøgelse blev støttet af Ministeriet for National Defense (MAB-105-070; MAB-106-077; MAB-107-032; Mab-107-065), Ministeriet for videnskab og teknologi (de fleste 107-2320-B016-016), Tri-Service General Hospital, nationalt forsvar Medical Center, Taiwan (TSGH-C106-046; TSGH-C106-115; TSGH-C107-041), og Cheng-Hsin General Hospital og National Defense Medical Center samarbejde (CH-NDMC-107-8).

De fedtvæv blev indhentet fra ortopædisk kirurgi, som attesteret af de institutionelle Review Board i Tri-Service General Hospital, Taipei, Taiwan, R.O.C. procedurer, der involverer dyr emner er blevet godkendt af Animal Care Udvalget på nationalt Defense Medical Center, Taiwan (R.O.C).
1. våd Spinning proces
<ol><li>
Løsning forberedelse
	<ol>
<li>Opløses 5 g gelatine pulver i 100 mL dobbeltdestilleret vand at få 5% (w/v) opløsningens koncentration.</li>
		<li>Bland...

<ol>
	<li>Bagnall, A. M., Jones, L., Duffy, S., Riemsima, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spinal+fixation+surgery+for+acute+traumatic+spinal+cord+injury.">Spinal fixation surgery for acute traumatic spinal cord injury.</a> Cochrane Database of Systematic Reviews. 1, 004725 (2008).</li><li>Fehlings, M. G., Perrin, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+and+timing+of+early+decompression+for+cervical+spinal+cord+injury:+update+with+a+review+of+recent+clinical+evidence.">The role and timing of early decompression for cervical spinal cord injury: update with a review of recent clinical evidence.</a> Injury. 36, 13-26 (2005).</li><li>Yang, L., Jones, N. R., Stoodley, M. A., Blumbergs, P. C., Brown, C. 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W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chondroitin+sulphate+proteoglycans+in+the+central+nervous+system:+changes+and+synthesis+after+injury.">Chondroitin sulphate proteoglycans in the central nervous system: changes and synthesis after injury.</a> Biochemical Society Transactions. 31, 335-336 (2003).</li><li>Fawcett, J. W., Asher, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+glial+scar+and+central+nervous+system+repair.">The glial scar and central nervous system repair.</a> Brain Research Bulletin. 49, 377-391 (1999).</li><li>Yang, Z., Mo, L., Duan, H., Li, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+chitosan/collagen+substrates+on+the+behavior+of+rat+neural+stem+cells.">Effects of chitosan/collagen substrates on the behavior of rat neural stem cells.</a> Science China Life Sciences. 53, 215-222 (2010).</li><li>Chawla, K. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fibrous Materials. , (1998).</li><li>Pickering, K. L., Aruan Efendy, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+recent+developments+in+natural+fibre+composites+and+their+mechanical+performance.">A review of recent developments in natural fibre composites and their mechanical performance.</a> Composites Part A-Applied Science and Manufacturing. 83, 98-112 (2016).</li><li>Lundgren, H. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+fibers+made+from+proteins.">Synthetic fibers made from proteins.</a> Advances in Protein Chemistry. 5, 305-351 (1954).</li><li>Radishevskii, M. B., Serkov, A. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coagulation+mechanism+in+wet+spinning+of+fibres.">Coagulation mechanism in wet spinning of fibres.</a> Fibre Chemistry. 37, 266-271 (2005).</li><li>Yannas, I. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Collagen+and+gelatin+in+the+solid+state.">Collagen and gelatin in the solid state.</a> Journal of Macromolecular Science Part C Polymer Reviews. 7, 49-106 (1972).</li><li>Baer, E., Cassidy, J. J., Hiltner, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hierarchical+structure+of+collagen+composite+Systems:+lessons+from+biology.">Hierarchical structure of collagen composite Systems: lessons from biology.</a> Pure and Applied Chemistry. 6, 961-973 (2009).</li><li>Harrington, W. F., Von Hippel, P. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+structure+of+collagen+and+gelatin.">The structure of collagen and gelatin.</a> Advances in Protein Chemistry. 16, 1-138 (1961).</li><li>Veis, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Macromolecular Chemistry of Gelatin. , (1994).</li><li>Freyman, T. M., Yannas, I. V., Gibson, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellular+materials+as+porous+scaffolds+for+tissue+engineering.">Cellular materials as porous scaffolds for tissue engineering.</a> Progress in Materials Science. 46, 273-282 (2001).</li><li>Michalczyk, K., Ziman, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nestin+structure+and+predicted+function+in+cellular+cytoskeletal+organization.">Nestin structure and predicted function in cellular cytoskeletal organization.</a> Histology and Histopathology. 20, 665-671 (2005).</li></ol>

Vi præsenterede udviklingen af gelatine-baseret Biomaterialer ved hjælp af en simpel våd spinning teknik, der kan anvendes i studiet af naturlige polymerer til væv revitalisering. Dette arbejde viste muligheden for gelatine fabrikation som en stor proteinkilde uden tilsætning af andre kilder, med formålet at optimere egenskaber af gelatine, selv. Udviklingen af gelatine-baseret Biomaterialer blev udelukkende udført i stuetemperatur (22-26 ° C). En blid løsning forberedelse er et kritisk skridt i protokollen, som...

Den seneste udvikling i væv revitalisering indebærer anvendelse af vævsmanipulering, som repræsenterer en udfordring for forbedring af nye terapeutiske strategier i medicinske behandlinger. For eksempel, udgør begrænset potentiale af nervesystemet regenerering, følgende skade eller sygdom, en væsentlig sundhedsproblem på verdensplan. På grund af kompleksiteten af patofysiologiske processer forbundet med nervesystemet, brug af traditionelle autograft eller gennemførelsen af stabilisering kirurgi har vist sig at tilbyde fordele i funktionelle resultater, men der er ingen stærke beviser for virkningerne af spinal fiksering kirurgi1,2. Væv på det beskadigede område er mistet og erstattet med hypertrophically induceret astrocytter3, til sidst danner en tæt glial ar4,5. Denne matrix fungerer som en barriere at blokke genopretning af nerve funktion6,7 og er således stærkt hindrer regenerering. Derfor, en passende fylde hullet materiale forventes at forhindre tab af væv og reducere dannelsen af ar-associerede bindevæv ved at opretholde integriteten af det beskadigede område, samt ved at give direkte udskiftning af neurale celler og kredsløb at fremme axon regenerering.
Polymere biomaterialer har været foretrukne som stilladser for væv revitalisering terapi, baseret på reguleringen af celle eller axon adfærd og væv progression gennem naturlige ekstracellulære matrix (ECM) støtte. Formatet fiber er almindeligvis betragtes som en byggesten for forskellige materialer, på grund af dens endimensional struktur8. Fibrene kan generelt fås ved at smelte ekstrudering eller våde spinning metode; men den store størrelse og omkostningerne ved udstyr og vanskeligheder ved at udføre disse metoder er udfordrende. Derudover har flertal af for arbejdet i forbindelse med polymer fibre været fokuseret på syntetiske eller komposit materialer. Naturlige polymerer som en kilde til biomateriale tilbyde bedre biokompatibilitet egenskaber for den menneskelige krop. Ikke desto mindre, for at få tilpasningen af naturlige polymer fibre er relativt mere vanskeligt end af syntetisk polymer kilder9. Konvertering af en naturlig polymer som en rig kilde til protein i biomateriale fibre er derfor en vigtig strategi — ikke kun kan biomateriale fibre blive direkte isoleret fra råvarer, således at man undgår en unødig transformation til monomerer, men den protein fibre har også et godt udseende og positiv egenskaber10.
I denne forbindelse, beskriver vi en billig forarbejdningsmetode til fremstilling af naturlige polymer fibre gennem det grundlæggende koncept af våde spinning, der kan implementeres på laboratoriet skala for vævsmanipulering. Våd spinning er udført af ekstrudering og koagulation af en polymer løsning til en egnet polymer nonsolvent. En passende, tyktflydende løsning doteret til koagulation medie forårsager polymer molekyler til at opløse. Gennem overgang fase glødetrådenes derefter mister deres opløselighed og er fældet i form af en solid polymer fase11. Henviser til dette begreb, udvidet vi derefter udvikling af gelatine i formen tube af en støbeprocessen, som anses for korrekt for væv revitalisering ansøgning. Derudover uløseligt, kan vi også udvikle enhver form af materialet fra gelatine fibre (fx gelatine conduit rullet op fra flere gelatine fibre), for andre ønskede applikationer.
Gelatine, biologisk nedbrydeligt naturlige polymerer, er dannet af denatureret og hydrolyseret kollagen, herunder eventuelle semicrystalline, amorf eller tredobbelt spiralformet tilstand af kollagen12. Det er velkendt, at kollagen er den væsentlige strukturelle protein i alle bindevævet af hvirveldyr og hvirvelløse dyr13,14, der svarer til protein struktur af de vigtigste ECM, der inducerer nerve vækst og samtidig erstatter en stor mængde af glykosaminoglykan udskilles i løbet af rygmarvsskader. Derfor ville brugen af gelatine som en kilde være et godt valg for enhver medicinsk køretøj. Udover at være en billig kilde, gelatine er også biologisk nedbrydeligt og cytocompatible og klinisk bevist at være en midlertidig fejl fyldstof15. Udviklet sig til en tube form, vise in vitro og in vivo prøver beskrevet her, at gelatine har en fremragende biokompatibilitet og egnethed for fremtidige tissue engineering applikationer. Kulturperler med menneskelige adipøst stamceller, gelatine rør forbedre Celledifferentiering af neurale stamceller ved hjælp af positive nestin farvning som neurale celle markør. Derudover forventes gelatine som fylde hullet materiale, som fremstillet ved den metode, der er etableret i denne undersøgelse, at være overskueligt og sikkert og til stor gavn væv ingeniører, der i øjeblikket udvikler korrelationsmaalinger naturlige polymerer til forbedring af væv regenerering strategier.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="4">Solution preparation:</td>
		</tr>
		<tr>
			<td>Gelatin type B (porcine)</td>
			<td>Ferak</td>
			<td>Art. -Nr. 10733</td>
			<td>500 g vial</td>
		</tr>
		<tr>
			<td>Wet spinning process:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Peristaltic pump</td>
			<td>Gilson</td>
			<td>Model M312</td>
			<td>Minipuls*3</td>
		</tr>
		<tr>
			<td>Plastic tube connector</td>
			<td>World Precision Instruments</td>
			<td>14011</td>
			<td>1 box</td>
		</tr>
		<tr>
			<td>Syringe</td>
			<td>Sterican</td>
			<td>5A06258541</td>
			<td>26Gx1/2&#34;(0.45 x 12mm)</td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Ferak</td>
			<td>Art. -Nr. 00010</td>
			<td>2.5 L vial</td>
		</tr>
		<tr>
			<td>Polycaprolactone CAPA 6500</td>
			<td>Perstorp</td>
			<td>24980-41-4</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Dichloromethane&#160;</td>
			<td>Scharlau</td>
			<td>CL03421000</td>
			<td>1 L vial</td>
		</tr>
		<tr>
			<td>Glass Pasteur pipette</td>
			<td>Fisher Scientific</td>
			<td>13-678-20A</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Hemostat</td>
			<td>Shinetec instruments</td>
			<td>ST-B021</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Peripheral venous catheter (Introcan Certo)</td>
			<td>B. Braun</td>
			<td>1B03258241</td>
			<td>24Gx3/4&#34;(0.7 x 19mm)</td>
		</tr>
		<tr>
			<td colspan="4">Morphology of the gelatin tube:</td>
		</tr>
		<tr>
			<td>Ion sputter coater machine&#160;</td>
			<td>Hitachi</td>
			<td>e1010</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Scanning electron microscopy</td>
			<td>Hitachi</td>
			<td>S-3000N</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Cultivation of cells on the gelatin tube:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Trypsin-EDTA</td>
			<td>Gibco</td>
			<td>488625</td>
			<td>100 mL vial</td>
		</tr>
		<tr>
			<td>Fetal bovine serum</td>
			<td>Gibco</td>
			<td>923119</td>
			<td>500 mL vial</td>
		</tr>
		<tr>
			<td>Dulbecco&#39;s modified Eagle&#39;s medium&#160;</td>
			<td>Gibco</td>
			<td>31600-034</td>
			<td>Powder</td>
		</tr>
		<tr>
			<td>Keratinocyte-SFM medium</td>
			<td>Gibco</td>
			<td>10744-019</td>
			<td>500 mL vial</td>
		</tr>
		<tr>
			<td>T25 culture flask</td>
			<td>TPP</td>
			<td>90025</td>
			<td>VENT type</td>
		</tr>
		<tr>
			<td>6-well plate</td>
			<td>Falcon</td>
			<td>1209938</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Immunocytochemistry:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Phospate-buffered saline</td>
			<td>Gibco</td>
			<td>654471</td>
			<td>500 mL vial</td>
		</tr>
		<tr>
			<td>Acetic acid glacial</td>
			<td>Ferak</td>
			<td>Art. -Nr. 00697</td>
			<td>500 mL vial</td>
		</tr>
		<tr>
			<td>NP-40 surfactant (Tergitol solution)</td>
			<td>Sigma</td>
			<td>056K0151</td>
			<td>500 mL vial</td>
		</tr>
		<tr>
			<td>Normal goat serum</td>
			<td>Vector Laboratories</td>
			<td>S-1000-20</td>
			<td>20 mL vial, concentrate</td>
		</tr>
		<tr>
			<td>Nestin (primary antibody)</td>
			<td>Santa Cruz Biotechnology</td>
			<td>SC-23927</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Donkey anti-mouse-fluorescein isothiocyanate (secondary antibody)</td>
			<td>Santa Cruz Biotechnology</td>
			<td>SC-2099</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Hoechst 33342</td>
			<td>Anaspec</td>
			<td>AS-83218</td>
			<td>5 mL vial</td>
		</tr>
		<tr>
			<td>In vivo biocompatibility test:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Tiletamine+zolazepam&#160;</td>
			<td>Virbac</td>
			<td>BC91</td>
			<td>5 mL vial</td>
		</tr>
		<tr>
			<td>Xylazine</td>
			<td>Bayer korea</td>
			<td>KR03227</td>
			<td>10 mL vial</td>
		</tr>
		<tr>
			<td>Ketoprofen</td>
			<td>Astar</td>
			<td>1406232</td>
			<td>2 mL vial</td>
		</tr>
		<tr>
			<td>Povidone-iodine solution</td>
			<td>Everstar</td>
			<td>HA161202</td>
			<td>4 L barrel</td>
		</tr>
		<tr>
			<td>Cefazolin</td>
			<td>China Chemical &#38; Pharmaceutical</td>
			<td>18P909</td>
			<td>1 g vial</td>
		</tr>
		<tr>
			<td>Scalpel blade</td>
			<td>Shinetec instruments</td>
			<td>ST-B021</td>
			<td>-</td>
		</tr>
		<tr>
			<td>Surgical scissor</td>
			<td>Shinetec instruments</td>
			<td>ST-B021</td>
			<td>-</td>
		</tr>
	</tbody>
</table>

wet-spinning-based molding process of gelatin for tissue regeneration

Denne artikel præsenterer en billig metode til at fremstille gelatine, som en naturlig polymer i monofilamenter fibre eller i andre passende former. Gennem den våde spinning metode, fremstilles gelatine fibre ved glat ekstrudering i en egnet koagulation medium. For at øge den funktionelle overfladen af disse gelatine fibre og deres evne til at efterligne funktionerne af væv, kan gelatine blive støbt i en tube form ved at henvise til dette begreb. Undersøgt af in vitro- og in vivo test, vise gelatine rør et stort potentiale for anvendelse i vævsmanipulering. Fungerer som en passende fylde hullet materiale, gelatine rør kan bruges til at erstatte væv i det beskadigede område (fx i nervøs eller hjerte-kar-systemet), samt at fremme regenerering af at yde en direkte udskiftning af stamceller og neurale kredsløb. Denne protokol indeholder en detaljeret procedure for at oprette en biomateriale, baseret på en naturlig polymer, og dets gennemførelse forventes at stor gavn udviklingen af korrelationsmaalinger naturlige polymerer, som bidrager til at realisere væv revitalisering strategier.

I denne undersøgelse udviklet vi med succes gelatine i fibre (fig. 2A) og rør (figur 2B, C) gennem begrebet brugervenlige våde spinning. Disse gelatine-baserede materialer kan udnyttes som enhver medicinsk værktøj, afhængigt af deres figurer. I betragtning af at den funktionelle overflade og ramme af sådanne materialer er mere velegnede til vævsregeneration, undersøgte vi biokompatibilit...

Watch this Scientific Journal Video about Wet-spinning-based Molding Process of Gelatin for Tissue Regeneration at JoVE.com

Wet-spinning-based Molding Process of Gelatin for Tissue Regeneration

Vi udviklede og beskrive en protokol baseret på begrebet våde spinning for opførelsen af gelatine-baseret Biomaterialer bruges til anvendelsen af vævsmanipulering.

Wet-spinning-baserede Molding proces af gelatine for vævsregeneration

This article presents an inexpensive method to fabricate gelatin, as a natural polymer, into monofilament fibers or other appropriate forms. Through the ...

Denne protokol forbedrer et grundlæggende begreb våd-spinning at udvikle et materiale fra en enkelt fiber strimmel i forskellige strimler, der kan bruges til enhver foretrukken medicinsk anvendelse. Denne teknik er enkel, billig, og kræver ikke tilsætning af syntetiske polymerer til tilpasning af de naturlige polymerer i en ressource af protein til materialer af interesse. Denne teknik kan udvides til biomateriale udvikling for drab kold behandling såsom central eller perifere nervesystem behandling, blodkar udskiftning, eller direkte urinveje rekonstruktion.Denne metode er beregnet til medicinsk anvendelse, herunder som en strategi for væv neuralisering eller regenerativ medicin. Denne teknik kan nemt implementeres af begyndere. Bemærk, at efter flere støbning gentagelser, bør kvaliteten af opløsningen altid kontrolleres for at opretholde en optimal dannelse.For at danne det våde roterende rør, først nedsænkes en 24 gauge med tre kvart tommer perifer venekateter i frisklavet gelatine opløsning i tre sekunder, efterfulgt af nedsænkning i frisklavet acetone opløsning i et minut. Gentag disse trin 20 gange. Efter den sidste acetone nedsænkning, lad det støbte rør tørre i fem minutter ved stuetemperatur, og bruge en hæmostat til omhyggeligt at overføre gelatinerøret fra kateteret til et glas Pasteur pipette med 2,5% polycaprolactone dichlormetan opløsning til en overnatning under-hood inkubation ved stuetemperatur.Den næste morgen, sterilisere gelatine i to timer under ultraviolet lys, før kortvarigt nedsænkning røret i 75% ethanol. Derefter vaskes røret to gange med stamcellemediet for at fjerne den resterende ethanol. For at dyrke gelatinerøret med cellekulturen skal du erstatte den supinate ende af humane fedtstamceller fra en dyrkningskolbe med en milliliter på 0,25%Trypsin-EDTA for en 3,5 minutters inkubation ved 37 grader Celsius og 5 % kuldioxid.Når cellerne er taget af, standses reaktionen med en milliliter føtalt kvægserum, og cellesuspensionen overføres til et mikrocentrifugerør. Cellerne opsamls ved centrifugering og opstimer pellet i en milliliter stamcellemedium. Derefter anbringes gelatinerøret i en brønd af en seks-brønds plade, der indeholder tre milliliter stamcellemedium.Efter optælling af cellerne, frø fire gange 10 til den fjerde af menneskelige fedt stamceller i røret for en to ugers inkubation i cellen kultur inkubator. Efter at have bekræftet det passende niveau af sedation ved manglende reaktion på tå knivspids i en kvindelig otte uger gammel Sprague Dawley rotte, barbere håret fra trapezius området og sterilisere den eksponerede hud med povidone-jod opløsning. Dæk rotten med sterile kirurgiske gardiner for at reducere bakteriel forurening af operationsstedet og bruge kirurgisk saks til at gøre en lavvandet, to centimeter lang hud snit.Placer gelatinerøret direkte ind i laget mellem fascia og musklen og brug en nylonsutur til at lukke såret. Derefter steriliseres snittet med povidone-jodopløsning. Inducere rotten via en intramuskulær injektion af ketoprofen og cefazolin og vedligeholde dyret under aseptiske forhold i syv dage.Denne brugervenlige våde spinning koncept kan bruges til at udvikle gelatine i fibre og rør. Morfologiske observationer af gelatinerøret ved scanning af elektronmikroskopi afslører en ikke særlig glat overflade med en indre diameter på mere end 200 mikrometer og en tykkelse på ca. 20 mikrometer. Farvning af en menneskelig fedt stamcellekultur gelatine rør til neuralcellemarkør udtryk viser en positiv farvning for markøren sammen med flere opdaget kerner tyder på, at cellerne kan trænge ind og overholde gelatine rør og differentiere i neurale progenitor celler.Implantation af gelatinerøret i fascialaget bekræfter dets sikkerhed og biokompatibilitet, da der ikke observeres tegn på rødme, hævelse eller andre inflammationssymptomer i det lokale væv, og røret er omgivet af veludviklet bindevæv. Mens du forsøger denne procedure på to punkt et, sikre nedsænkning af formen i den specifikke belægning tid i hver løsning er meget vigtigt at opbygge en præcis rørform. Efter denne procedure, vores eksperimenter bruger dyremodel af human sygdom kan udføres til præcist at undersøge resultatet af biomaterialer til væv regenerering strategi.Efter sin udvikling, denne teknik banede vejen for forskere i at udvikle enkle korrelerende natur polymerer i enhver form for materiale til en besluttet medicinsk anvendelse. Under normal brug tilstand, polycaprolactone dichlormethan opløsning anses for at udgøre minimal miljøfare, men glem ikke at udføre nogen skridt med dette kemikalie i en passende biosikkerhed kabinet.

wet-spinning-based-molding-process-of-gelatin-for-tissue-regeneration

Research

JoVE Journal

Bioengineering

Expression, Isolation, and Purification of Soluble and Insoluble Biotinylated Proteins for Nerve Tissue Regeneration

Recombinant protein engineering has utilized Escherichia coli (E. coli) expression systems for nearly 4 decades, and today E. coli is still the most widely used host organism. The flexibility of the system allows for the addition of moieties such as a biotin tag (for streptavidin interactions) and larger functional proteins like green fluorescent protein or cherry red protein. Also, the integration of unnatural amino acids like metal ion chelators, uniquely reactive functional groups, spectroscopic probes, and molecules imparting post-translational modifications has enabled better manipulation of protein properties and functionalities. As a result this technique creates customizable fusion proteins that offer significant utility for various fields of research. More specifically, the biotinylatable protein sequence has been incorporated into many target proteins because of the high affinity interaction between biotin with avidin and streptavidin. This addition has aided in enhancing detection and purification of tagged proteins as well as opening the way for secondary applications such as cell sorting. Thus, biotin-labeled molecules show an increasing and widespread influence in bioindustrial and biomedical fields. For the purpose of our research we have engineered recombinant biotinylated fusion proteins containing nerve growth factor (NGF) and semaphorin3A (Sema3A) functional regions. We have reported previously how these biotinylated fusion proteins, along with other active protein sequences, can be tethered to biomaterials for tissue engineering and regenerative purposes. This protocol outlines the basics of engineering biotinylatable proteins at the milligram scale, utilizing&#160; a T7 lac inducible vector and E. coli expression hosts, starting from transformation to scale-up and purification.

Developing biotinylatable fusion proteins has many potential applications in various fields of research. Recombinant protein engineering is a straight forward procedure that is cost-effective, providing high yields of custom-designed proteins.

Ekspression, isolation og oprensning af opløselige og uopløselige Biotinylerede Proteiner til nervevæv Regeneration

Recombinant protein engineering has utilized Escherichia coli (E. coli) expression systems for nearly 4 decades, and today E. coli is still the most ...

Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

We have devised a method for low-cost and rapid prototyping of liquid elastomer rubber injection molded devices by using fused deposition modeling 3D printers for mold design and a modified desiccator as a liquid injection system.

Hurtig og Lavprisselskaber Prototyping af Medical Devices Brug 3D Trykt støbeforme til flydende Injection Molding

Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using ...

Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. Collagen has been extensively used for a wide range of biomedical applications and is considered a valid alternative to synthetic materials due to its inherent biocompatibility (i.e., low antigenicity, inflammation, and cytotoxic responses). However, the limited mechanical properties and the related low hand-ability of collagen gels have hampered their use as scaffold materials for vascular tissue engineering. Therefore, the rationale behind this work was first to engineer cellularized collagen gels into a tubular-shaped geometry and second to enhance smooth muscle cells driven reorganization of collagen matrix to obtain tissues stiff enough to be handled.
The strategy described here is based on the direct assembling of collagen and smooth muscle cells (construct) in a 3D cylindrical geometry with the use of a molding technique. This process requires a maturation period, during which the constructs are cultured in a bioreactor under static conditions (without applied external dynamic mechanical constraints) for 1 or 2 weeks. The &#8220;static bioreactor&#8221; provides a monitored and controlled sterile environment (pH, temperature, gas exchange, nutrient supply and waste removal) to the constructs. During culture period, thickness measurements were performed to evaluate the cells-driven remodeling of the collagen matrix, and glucose consumption and lactate production rates were measured to monitor the cells metabolic activity. Finally, mechanical and viscoelastic properties were assessed for the resulting tubular constructs. To this end, specific protocols and a focused know-how (manipulation, gripping, working in hydrated environment, and so on) were developed to characterize the engineered tissues.

In this work, we present a technique for the rapid fabrication of living vascular tissues by direct culturing of collagen, smooth muscle cells and endothelial cells. In addition, a new protocol for the mechanical characterization of engineered vascular tissues is described.

Engineering 3D Cellularized kollagengeler for Vascular Tissue Regeneration

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. ...

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to intrinsic parameters within the process allow a high degree of control over scaffold characteristics including fiber diameter, alignment and porosity. By developing scaffolds with similar dimensions and topographies to organ- or tissue-specific extracellular matrices (ECM), micro-environments representative to those that cells are exposed to in situ can be created. 
The airway bronchiole wall, comprised of three main micro-environments, was selected as a model tissue. Using decellularized airway ECM as a guide, we electrospun the non-degradable polymer, polyethylene terephthalate (PET), by three different protocols to produce three individual electrospun scaffolds optimized for epithelial, fibroblast or smooth muscle cell-culture. Using a commercially available bioreactor system, we stably co-cultured the three cell-types to provide an in vitro model of the airway wall over an extended time period.
This model highlights the potential for such methods being employed in in vitro diagnostic studies investigating important inter-cellular cross-talk mechanisms or assessing novel pharmaceutical targets, by providing a relevant platform to allow the culture of fully differentiated adult cells within 3D, tissue-specific environments.

Adapting the Electrospinning Process to Provide Three Unique Environments for a Tri-layered In Vitro Model of the Airway Wall

Advancements in biomaterial technologies enable the development of three-dimensional multi-cell-type constructs. We have developed electrospinning protocols to produce three individual scaffolds to culture the main structural cells of the airway to provide a 3D in vitro model of the airway bronchiole wall.

Tilpasning af Electrospinning proces med at give tre unikke miljøer for en Tri-lags<em&gt; In vitro</em&gt; Model af Airway Wall

Electrospinning is a highly adaptable method producing porous 3D fibrous scaffolds that can be exploited in in vitro cell culture. Alterations to ...

Qualitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae Using 2D Gas Chromatography with Time-of-flight Mass Spectrometry

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in complex mixtures. It is often used to analyze gasoline, jet fuel, diesel, bio-diesel and the organic fraction of bio-crude/bio-oil. In most of those analyses, the first dimension of separation is non-polar, followed by a polar separation. The aqueous fractions of bio-crude and other aqueous samples from biofuels production have been examined with similar column combinations. However, sample preparation techniques such as derivatization, solvent extraction, and solid-phase extraction were necessary prior to analysis. In this study, aqueous fractions obtained from the hydrothermal liquefaction of algae were characterized by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry without prior sample preparation techniques using a polar separation in the first dimension followed by a non-polar separation in the second. Two-dimensional plots from this analysis were compared with those obtained from the more traditional column configuration. Results from qualitative characterization of the aqueous fractions of algal bio-crude are discussed in detail. The advantages of using a polar separation followed by a non-polar separation for characterization of organics in aqueous samples by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry are highlighted.

A two-dimensional gas chromatography-time-of-flight mass spectrometry method is described for characterization of the aqueous fraction of bio-crude produced from hydrothermal liquefaction of algae. This protocol can also be employed to analyze the aqueous fraction of liquid products from fast pyrolysis, catalytic fast pyrolysis, catalytic deoxygenation and hydro-treating.

Kvalitativ Karakterisering af den vandige fraktion fra Hydrotermisk fortætning af alger ved hjælp af 2D gaskromatografi med Time-of-flight massespektrometri

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in ...

Alternating Magnetic Field-Responsive Hybrid Gelatin Microgels for Controlled Drug Release

Magnetically-responsive nano/micro-engineered biomaterials that enable a tightly controlled, on-demand drug delivery have been developed as new types of smart soft devices for biomedical applications. Although a number of magnetically-responsive drug delivery systems have demonstrated efficacies through either in vitro proof of concept studies or in vivo preclinical applications, their use in clinical settings is still limited by their insufficient biocompatibility or biodegradability. Additionally, many of the existing platforms rely on sophisticated techniques for their fabrications. We recently demonstrated the fabrication of biodegradable, gelatin-based thermo-responsive microgel by physically entrapping poly(N-isopropylacrylamide-co-acrylamide) chains as a minor component within a three-dimensional gelatin network. In this study, we present a facile method to fabricate a biodegradable drug release platform that enables a magneto-thermally triggered drug release. This was achieved by incorporating superparamagnetic iron oxide nanoparticles and thermo-responsive polymers within gelatin-based colloidal microgels, in conjunction with an alternating magnetic field application system.

We present a facile method to fabricate a biodegradable gelatin-based drug release platform that is magneto-thermally responsive. This was achieved by incorporating superparamagnetic iron oxide nanoparticles and poly(N-isopropylacrylamide-co-acrylamide) within a spherical gelatin micro-network crosslinked by genipin, in conjunction with an alternating magnetic field application system.

Vekslende magnetfelt-Responsive Hybrid Gelatine Mikrogeler for Controlled Drug frigivelse

Magnetically-responsive nano/micro-engineered biomaterials that enable a tightly controlled, on-demand drug delivery have been developed as new types of ...

A Paired Bead and Magnet Array for Molding Microwells with Variable Concave Geometries

A spheroid culture is a useful tool for understanding cellular behavior in that it provides an in vivo-like three-dimensional environment. Various spheroid production methods such as non-adhesive surfaces, spinner flasks, hanging drops, and microwells have been used in studies of cell-to-cell interaction, immune-activation, drug screening, stem cell differentiation, and organoid generation. Among these methods, microwells with a three-dimensional concave geometry have gained the attention of scientists and engineers, given their advantages of uniform-sized spheroid generation and the ease with which the responses of individual spheroids can be monitored. Even though cost-effective methods such as the use of flexible membranes and ice lithography have been proposed, these techniques incur serious drawbacks such as difficulty in controlling the pattern sizes, achievement of high aspect ratios, and production of larger areas of microwells. To overcome these problems, we propose a robust method for fabricating concave microwells without the need for complex high-cost facilities. This method utilizes a 30 x 30 through-hole array, several hundred micrometer-order steel beads, and magnetic force to fabricate 900 microwells in a 3 cm x 3 cm polydimethylsiloxane (PDMS) substrate. To demonstrate the applicability of our method to cell biological applications, we cultured adipose stem cells for 3 days and successfully produced spheroids using our microwell platform. In addition, we performed a magnetostatic simulation to investigate the mechanism, whereby magnetic force was used to trap the steel beads in the through-holes. We believe that the proposed microwell fabrication method could be applied to many spheroid-based cellular studies such as drug screening, tissue regeneration, stem cell differentiation, and cancer metastasis.

This manuscript introduces a robust method of fabricating concave microwells without the need for complex high-cost facilities. Using magnetic force, steel beads, and a through-hole array, several hundred microwells were formed in a 3 cm x 3 cm polydimethylsiloxane (PDMS) substrate.

En parret perle og Magnet Array for Molding Microwells med variabel konkave geometrier

A spheroid culture is a useful tool for understanding cellular behavior in that it provides an in vivo-like three-dimensional environment. Various ...

Three-dimensional Tissue Engineered Aligned Astrocyte Networks to Recapitulate Developmental Mechanisms and Facilitate Nervous System Regeneration

Neurotrauma and neurodegenerative disease often result in lasting neurological deficits due to the limited capacity of the central nervous system (CNS) to replace lost neurons and regenerate axonal pathways. However, during nervous system development, neuronal migration and axonal extension often occur along pathways formed by other cells, referred to as &#34;living scaffolds&#34;. Seeking to emulate these mechanisms and to design a strategy that circumvents the inhibitory environment of the CNS, this manuscript presents a protocol to fabricate tissue engineered astrocyte-based &#34;living scaffolds&#34;. To create these constructs, we employed a novel biomaterial encasement scheme to induce astrocytes to self-assemble into dense three-dimensional bundles of bipolar longitudinally-aligned somata and processes. First, hollow hydrogel micro-columns were assembled, and the inner lumen was coated with collagen extracellular-matrix. Dissociated cerebral cortical astrocytes were then delivered into the lumen of the cylindrical micro-column and, at a critical inner diameter of &#60;350 &#181;m, spontaneously self-aligned and contracted to produce long fiber-like cables consisting of dense bundles of astrocyte processes and collagen fibrils measuring &#60;150 &#181;m in diameter yet extending several cm in length. These engineered living scaffolds exhibited &#62;97% cell viability and were virtually exclusively comprised of astrocytes expressing a combination of the intermediate filament proteins glial-fibrillary acidic protein (GFAP), vimentin, and nestin. These aligned astrocyte networks were found to provide a permissive substrate for neuronal attachment and aligned neurite extension. Moreover, these constructs maintain integrity and alignment when extracted from the hydrogel encasement, making them suitable for CNS implantation. These preformed constructs structurally emulate key cytoarchitectural elements of naturally occurring glial-based &#34;living scaffolds&#34; in vivo. As such, these engineered living scaffolds may serve as test-beds to study neurodevelopmental mechanisms in vitro or facilitate neuroregeneration by directing neuronal migration and/or axonal pathfinding following CNS degeneration in vivo.

We showcase the development of self-assembled, three-dimensional bundles of longitudinally aligned astrocytic somata and processes within a novel biomaterial encasement. These engineered &#34;living scaffolds&#34;, exhibiting micron-scale diameter yet extending centimeters in length, may serve as test-beds to study neurodevelopmental mechanisms or facilitate neuroregeneration by directing neuronal migration and/or axonal pathfinding.

Tre-dimensionelle Tissue Engineering justeret Astrocyte netværk for at sammenfatte udviklingsmæssige mekanismer og lette nervesystem regenerering

Neurotrauma and neurodegenerative disease often result in lasting neurological deficits due to the limited capacity of the central nervous system (CNS) to ...

Patterning the Geometry of Human Embryonic Stem Cell Colonies on Compliant Substrates to Control Tissue-Level Mechanics

Human embryonic stem cells demonstrate a unique ability to respond to morphogens in vitro by self-organizing patterns of cell fate specification that correspond to primary germ layer formation during embryogenesis. Thus, these cells represent a powerful tool with which to examine the mechanisms that drive early human development. We have developed a method to culture human embryonic stem cells in confined colonies on compliant substrates that provides control over both the geometry of the colonies and their mechanical environment in order to recapitulate the physical parameters that underlie embryogenesis. The key feature of this method is the ability to generate polyacrylamide hydrogels with defined patterns of extracellular matrix ligand at the surface to promote cell attachment. This is achieved by fabricating stencils with the desired geometric patterns, using these stencils to create patterns of extracellular matrix ligand on glass coverslips, and transferring these patterns to polyacrylamide hydrogels during polymerization. This method is also compatible with traction force microscopy, allowing the user to measure and map the distribution of cell-generated forces within the confined colonies. In combination with standard biochemical assays, these measurements can be used to examine the role mechanical cues play in fate specification and morphogenesis during early human development.

Extracellular matrix ligands can be patterned onto polyacrylamide hydrogels to enable the culture of human embryonic stem cells in confined colonies on compliant substrates. This method can be combined with traction force microscopy and biochemical assays to examine the interplay between tissue geometry, cell-generated forces, and fate specification.

Mønster for geometrien af humane embryonale stamcelle kolonier på kompatible substrater til kontrol af Vævsniveau mekanik

Human embryonic stem cells demonstrate a unique ability to respond to morphogens in vitro by self-organizing patterns of cell fate specification that ...

Protocols of 3D Bioprinting of Gelatin Methacryloyl Hydrogel Based Bioinks

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed from mammal collagen. Thus, the arginine-glycine-aspartic acid (RGD) sequences and target motifs of matrix metalloproteinase (MMP) remain on the molecular chains, which help achieve cell attachment and degradation. Furthermore, formation properties of GelMA are versatile. The methacrylamide groups allow a material to become rapidly crosslinked under light irradiation in the presence of a photoinitiator. Therefore, it makes great sense to establish suitable methods for synthesizing three-dimensional (3D) structures with this promising material. However, its low viscosity restricts GelMA's printability. Presented here are methods to carry out 3D bioprinting of GelMA hydrogels, namely the fabrication of GelMA microspheres, GelMA fibers, GelMA complex structures, and GelMA-based microfluidic chips. The resulting structures and biocompatibility of the materials as well as the printing methods are discussed. It is believed that this protocol may serve as a bridge between previously applied biomaterials and GelMA as well as contribute to the establishment of GelMA-based 3D architectures for biomedical applications.

Presented here is a method for the 3D bioprinting of gelatin methacryloyl.

Protokoller af 3D Bioprinting af gelatine Methacryloyl hydrogel baserede Bioinks

Gelatin methacryloyl (GelMA) has become a popular biomaterial in the field of bioprinting. The derivation of this material is gelatin, which is hydrolyzed ...