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 studien ble støttet av det nasjonale Forsvarsdepartementet (MAB-105-070; MAB-106-077; MAB-107-032; Mab-107-065), departementet for vitenskap og teknologi (de fleste 107-2320-B016-016), Tri-Service General Hospital, nasjonale forsvar Medical Center, Taiwan (TSGH-C106-046; TSGH-C106-115; TSGH-C107-041), og Cheng-Hsin General Hospital og National Defense Medical Center samarbeid (CH-NDMC-107-8).

Fett vev ble Hentet fra lever slik den institusjonelle gjennomgang styret for Tri-Service General Hospital, Taipei, Taiwan, R.O.C. prosedyrer som involverer dyr fag er godkjent av dyr omsorg komiteen på nasjonalt Forsvar Medical Center, Taiwan (R.O.C).
1. fukt Spinning prosessen
<ol><li>
Løsning forberedelse
	<ol>
<li>Oppløse 5 g av gelatin pulver i 100 mL dobbel-destillert vann å få 5% (w/v) løsning konsentrasjon.</li>
		<li>Rør blandingen langsomt ved 60-70 ° C ove...

<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. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excitotoxic+model+of+post-traumatic+syringomyelia+in+the+rat.">Excitotoxic model of post-traumatic syringomyelia in the rat.</a> Spine. 26, 1842-1849 (2001).</li><li>Rolls, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two+faces+of+chondroitin+sulfate+proteoglycan+in+spinal+cord+repair:+a+role+in+microglia/macrophage+activation.">Two faces of chondroitin sulfate proteoglycan in spinal cord repair: a role in microglia/macrophage activation.</a> PLoS Medicine. 5, 1262-1277 (2008).</li><li>Properzi, F., Asher, R. A., Fawcett, J. 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 presentert utviklingen av gelatin-baserte biologisk materiale ved hjelp av en enkel våt spinning teknikk som kan brukes i studiet av naturlige polymerer for vev gjenfødelse. Dette arbeidet viste at gelatin fabrikasjon som en stor proteinkilde uten tilsetning av andre kilder, med sikte på å optimalisere egenskapene av seg selv. Utviklingen av gelatin-baserte biologisk materiale ble helt gjennomført i romtemperatur (22-26 ° C). En mild løsning forberedelse er en avgjørende skritt i protokollen, som opprettholder...

Den nyeste utviklingen i vev gjenfødelse omfatter bruk av vev utvikling, som representerer en utfordring for forbedring av nye strategier i medisinske behandlinger. For eksempel utgjør begrenset potensialet i nervesystemet gjenfødelse, følgende skade eller sykdom, et betydelig helseproblem over hele verden. Komplekse patofysiologiske prosesser knyttet nervesystemet, bruk av tradisjonelle autograft eller implementering av stabilisering kirurgi har vist seg å tilby fordeler i funksjonelle resultater, men det er ingen sterke bevis for effekten av spinal fiksering kirurgi1,2. Vevet på den skadede delen er tapt og erstattet hypertrophically indusert astrocyttene3til slutt danne en tett glial arr4,5. Denne matrisen fungerer som en barriere som blokker utvinning av nerve funksjon6,7 og er dermed et stort hinder gjenfødelse. Derfor en egnet gapet fyllmasse forventes å hindre tap av vev og redusere dannelsen av arr-assosiert bindevev opprettholde integriteten til den skadede delen og gir direkte utskifting av neural celler og krets å fremme axon regenerering.
Polymere biologisk materiale er foretrukket som stillaser for vev regenerasjon terapi, basert på regulering av cellen eller axon atferd og vev progresjon gjennom naturlig ekstracellulær matrix (EFM) støtte. Fiber formatet regnes vanligvis som en byggestein for ulike materialer, på grunn av sin endimensjonal struktur8. Fibrene kan vanligvis oppnås ved smelte ekstrudering eller våt spinning metoden; men er størrelsen og utstyret og vanskeligheter for å utføre disse metodene utfordrende. Dessuten, har fleste av arbeidet knyttet til polymer fiber vært fokusert på syntetisk eller komposittmaterialer. Naturlig polymerer som biomateriale tilbyr bedre biocompatibility egenskaper for kroppen. Likevel, for å få justeringen av naturlige polymer fiber er relativt vanskeligere enn Syntetisk polymer kilder9. Derfor konvertering av en naturlig polymer som en rik kilde til protein i biomateriale fiber er en viktig strategi, ikke bare kan biomateriale fiber være direkte isolert fra råstoff, dermed unngår en unødvendig transformasjon til monomerer, men protein fiber har også et godt utseende og gode egenskaper10.
I denne forbindelse, beskriver vi en billig behandlingsmetode for produksjon av naturlig polymer fiber gjennom de grunnleggende konseptene for våt spinning, som kan gjennomføres på laboratoriet skala tissue engineering. Våt spinning utføres av ekstrudering og koagulering av en polymer løsning til en egnet polymer nonsolvent. En passende, tyktflytende løsning dopet i koagulering medium fører til polymer molekyler å oppløse. Gjennom fase overgangen, filamenter deretter mister deres løselighet og er utløst i form av en solid polymer fase11. Henvise til dette konseptet, utvidet vi så utviklingen av skjemaet rør av en molding prosess, som er riktig for vev gjenfødelse program. Dessuten, egentlig, vi kan også utvikle en figur av materiale fra gelatin fiber (f.eks gelatin kanal rullet av flere gelatin fiber), andre ønsket programmer.
Gelatin, en naturlig biologisk nedbrytbart polymer er dannet av utarmet og hydrolyzed kollagen, inkludert noen semicrystalline, amorf eller trippel spiralformede stat kollagen12. Det er velkjent at kollagen er essensielle strukturelle proteinet i alle bindevev av virveldyr og virvelløse dyr13,14, som ligner på protein oppbygning viktigste ECM som induserer nerve vekst og samtidig, erstatter en stor mengde glycosaminoglycan utskilles i løpet av ryggmargsskade. Derfor ville bruk av som være et godt valg for alle medisinske kjøretøy. Foruten å være en billig kilde, gelatin er også biologisk nedbrytbart og cytocompatible og klinisk bevist å være en midlertidig feil filler15. Utviklet til en tube, viser i vitro og in vivo tester beskrevet her at gelatin har en utmerket biocompatibility og egnethet for fremtidige vev utvikling programmer. Kultivert med menneskelige adipose stamceller, gelatin rør forbedre celledifferensiering i nevrale stamceller ved hjelp av positivt nestin flekker som en neural celle markør. Videre er gelatin som fyller gapet materiale, som produseres av metoden i denne studien forventet å være håndterlig og trygt og stor nytte vev ingeniører som utvikler for tiden correlative naturlig polymerer for styrking av vev gjenfødelse 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 artikkelen presenterer en rimelig metode for å dikte gelatin, som en naturlig polymer monofilament fiber eller andre passende former. Gjennom den våte spinning metoden, er gelatin fiber produsert av glatt ekstrudering i et egnet koagulering medium. For å øke funksjonelle overflaten av disse gelatin fiber og deres evne til å etterligne funksjoner i vev, kan gelatin støpes inn i en rørform ved å henvise til dette konseptet. Gelatin rør undersøkt av i vitro og in vivo tester, og viser et stort potensial for programmet i vev engineering. Fungerer som en egnet fylle gapet materiale, gelatin rør kan brukes til å erstatte vevet i den skadede delen (f.eks i nervøs eller kardiovaskulære systemet), samt å fremme regenerering av skaffer en direkte erstatning av stamceller og nevrale kretser. Denne protokollen gir en detaljert fremgangsmåte for å opprette en biomateriale basert på en naturlig polymer, og gjennomføringen forventes å ha stor nytte utviklingen av correlative naturlig polymerer, som bidrar til å realisere vev gjenfødelse strategier.

I denne studien utviklet vi lykkes gelatin i fiber (figur 2A) og rør (figur 2B, C) gjennom brukervennlig våt spinning konseptet. Disse gelatin-baserte materialer kan benyttes som en medisinsk verktøy, avhengig av figurene. Tatt i betraktning at funksjonelle overflaten og rammen av slike materialer er mer egnet for vev gjenfødelse, undersøkt vi biokompatibilitet av gelatin rør av utføre i v...

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 utviklet og beskrive en protokoll basert på våt spinning konseptet, for bygging av gelatin-baserte biologisk materiale brukes for anvendelse av vev engineering.

Våt-spinning-baserte Molding prosessen med Gelatin for vev gjenfødelse

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

Denne protokollen forbedrer et grunnleggende konsept for våtspinne for å utvikle et materiale fra en enkelt fiberstripe til ulike strimler som kan brukes til enhver foretrukket medisinsk applikasjon. Denne teknikken er enkel, billig, og krever ikke tilsetning av syntetiske polymerer for tilpasning av de naturlige polymerene til en ressurs av protein for materialer av interesse. Denne teknikken kan utvides til biomateriale utvikling for å drepe kald terapi som sentral eller perifer nervesystemet behandling, blodkar erstatning, eller direkte urinveis rekonstruksjon.Denne metoden er ment for medisinsk anvendelse, inkludert som en strategi for vev neuralisering eller regenerativ medisin. Denne teknikken kan enkelt implementeres av nybegynnere. Merk at etter flere støperepetisjoner bør kvaliteten på løsningen alltid kontrolleres for å opprettholde en optimal formasjon.For å danne det våte spinnrøret, senk først en 24-gauge med tre kvart tommers perifert venekateter i nylaget gelatinløsning i tre sekunder, etterfulgt av nedsenking i nylaget acetonløsning i ett minutt. Gjenta disse trinnene 20 ganger. Etter den siste aceton nedsenking, la det støpte røret tørke i fem minutter ved romtemperatur, og bruk en hemostat til å forsiktig overføre gelatinrøret fra kateteret til en glass Pasteur pipette med 2,5% polycaprolactone diklormetanløsning for en overnatting under panser inkubasjon ved romtemperatur.Neste morgen steriliser gelatinen i to timer under ultrafiolett lys før du kort senker røret i 75% etanol. Vask deretter røret to ganger med stamcellemedium for å fjerne gjenværende etanol. For å dyrke gelatinrøret med cellekulturen, erstatt den supinate enden av menneskelige fettstamceller fra en kulturkolbe med en milliliter på 0,25% Trypsin-EDTA for en 3,5 minutters inkubasjon ved 37 grader Celsius og 5% karbondioksid.Når cellene har løsnet, arrester reaksjonen med en milliliter fosterbovinserum og overfør cellefjæringen til et mikrocentrifugerør. Samle cellene ved sentrifugering og resuspend pellet i en milliliter stamcelle medium. Legg deretter gelatinrøret i en brønn av en seksbrønns plate som inneholder tre milliliter stamcellemedium.Etter å ha talt cellene, frø fire ganger 10 til den fjerde av menneskelige fettstamceller inn i røret for en to ukers inkubasjon i cellekulturinkubatoren. Etter å ha bekreftet riktig nivå av sedasjon ved mangel på respons på tåklemme i en kvinnelig åtte uker gammel Sprague Dawley rotte, barber håret fra trapezius-området og steriliser den eksponerte huden med povidon-jodløsning. Dekk rotten med sterile kirurgiske gardiner for å redusere bakteriell forurensning av operasjonsstedet og bruk kirurgisk saks for å lage et grunt, to centimeter langt hudsnitt.Plasser gelatinrøret direkte inn i laget mellom fascia og muskelen og bruk en nylonsutur for å lukke såret. Steriliser deretter snittet med povidon-jodoppløsning. Indusere rotten via en intramuskulær injeksjon av ketoprofen og cefazolin og opprettholde dyret under aseptiske forhold i syv dager.Dette brukervennlige våtspinnekonseptet kan brukes til å utvikle gelatin til fibre og rør. Morfologiske observasjoner av gelatinrøret ved å skanne elektronmikroskopi avslører en ikke veldig glatt overflate med en større enn 200 mikrometer indre diameter og en tykkelse på ca 20 mikrometer. Farging av en menneskelig fett stamcellekultur gelatinrør for nevrale cellemarkøruttrykk viser en positiv farging for markøren sammen med flere oppdagede kjerner som tyder på at cellene kan trenge inn og holde seg til gelatinrøret og differensiere til nevrale stamceller.Implantasjon av gelatinrøret i fascialaget bekrefter sikkerhet og biokompatibilitet, da ingen indikasjon på rødhet, hevelse eller andre betennelsessymptomer observeres i det lokale vevet og røret er omgitt av velutviklet bindevev. Mens du prøver denne prosedyren av to punkt en, sikre nedsenking av formen i den spesifikke beleggtiden i hver løsning er svært viktig for å bygge opp en presis rørform. Etter denne prosedyren bruker våre eksperimenter dyremodell av menneskelig sykdom kan utføres for å nøyaktig undersøke utfallet av biomaterialene for vevregenereringsstrategi.Etter utviklingen banet denne teknikken vei for forskere i å utvikle enkle korrelative naturpolymerer til alle typer materiale for en bestemt medisinsk applikasjon. Under normal bruk tilstand, polycaprolactone dichloromethane løsningen anses å presentere minimal miljøfare, men ikke glem å utføre noen trinn med dette kjemikaliet i en passende biosikkerhet kabinett.

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.

Expression, Isolation, og Rensing av løselig og uløselig Biotinylated Proteiner for nervevev 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.

Rask og Rimelig Prototyping av medisinsk utstyr Bruk av 3D Trykt Stanse for Liquid 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.

Ingeniør 3D Cellularized Kollagen Geleer til Vaskulær 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 av electro prosess for å gi tre unike miljøer for en Tri-lag<em&gt; In Vitro</em&gt; Modell av 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 av den vandige fraksjon fra Hydrothermal kondensering av Alger Bruke 2D gasskromatografi 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 Gelatin mikrogeler for kontrollert legemiddeldosering

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 sammenkoblet perle og Magnet matrise 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.

Tredimensjonale vev utvikling justert astrocytter nettverk å Recapitulate utviklingsmessige mekanismer og tilrettelegge nervesystemet gjenfødelse

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.

Mønstre geometrien av menneskelige embryonale Stamcelle kolonier på kompatible underlag for å kontrollere vevs nivået mekanikk

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 av 3D Bioprinting av gelatin Methacryloyl hydrogel basert Bioinks

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