이 연구는 LSH 2Treat 프로그램 (436001003)과 네덜란드 신장 재단 (14a2d507)의 일환으로 ZonMw에 의해 재정적으로 지원됩니다. N.A.K.는 유럽 연구 위원회 (851960)의 지원을 인정합니다. 네덜란드 과학연구기구(024.003.013)가 후원한 중력프로그램 '재료 중심재생'을 감사하게 인정합니다.

저자는 공개 할 것이 없습니다.

본 명세서에 기재된 생물반응기는 관내 반사성 스캐폴드에서 염증 및 조직 재생에 대한 전단 스트레스 및 순환 스트레칭의 개별 및 결합된 효과의 기여도를 체계적으로 평가할 수 있다. 또한 이 방법을 사용하면 대표적인 결과 섹션에서 예시된 바와 같이 혈관 구조에서 다양한 분석을 수행할 수 있습니다. 이러한 결과는 TEVG 구조의 성장과 리모델링 모두에 다양한 혈역학 적재 체제(즉, 전단및 스?...

심혈관 조직 공학(TE)은 현재 사용되는 영구 심혈관 보철물(예를 들어, 혈관 이식, 심장 판막 교체)에 대한 대체 치료 옵션으로 추구되고 있으며, 이는 환자의 큰 코호트에 대해 최적이 아니다1,2,3,4. 많은 수요가 응용 프로그램은 조직 엔지니어링 혈관 이식편 (TEVGs)5,6 및 심장 판막 (TEHV)7,8을포함한다. 대부분의 경우, 심장 혈관 TE 방법론은 새로운 조직이 형성될 수 있는 유익한 발판역할을 하는 개역 가능한 생체 재료(천연 또는 합성)를 사용합니다. 새로운 조직의 형성은 체외에서 완전히 설계될 수 있으며, 세포와 함께 스캐폴드를 시드하고 이식 전에 생체 반응기에서 배양하여(체외TE)9,10,11,또는 직접 앉아서 합성 스캐폴드가 체내에서 직접 새로운 조직의 형성을 유도하기 위해 사전 배양없이 이식된다( 12) 1,12. 시험관 내 및 시투 심혈관 TE 접근법의 경우 성공적인 기능성 재생은 이식된 구조에 대한 숙주 면역 반응과 적절한 생체 기계적 적재모두에 크게 의존합니다.
심혈관 TE용 생체역학적 하중의 중요성은15. 심혈관 임플란트의 경우, 스캐폴드를 채우는 세포는 혈역학적 환경의 결과로 발생하는 순환 스트레칭및 전단 응력에 노출됩니다. 수많은 연구는 콜라겐16,17,18,19,글리코소미노글리산 (GAGs)20,및 엘라스틴(21,22)및 다양한 세포 유형에 의해 매트릭스 성분의 형성에 (순환) 스트레칭의 자극 효과를보고했다. 예를 들어, 황 외는 혈관생물반응기(23)를이용하여 체외 TEVG에서 콜라겐 및 엘라스틴의 증착 및 조직을 상승시키는 양축 스트레칭을 입증했다. 강조는 일반적으로 지배적 인 부하로 스트레칭에 놓여 있지만, 이러한 연구는 종종 샘플이 전단 흐름에 노출되는 흐름 중심의 생물 반응기를 사용합니다. 3D의 조직 형성과 염증에 대한 전단 응력의 고립 된 영향에 대해서는 상대적으로 거의 알려져 없지만 일부 데이터를 사용할 수 있습니다. 예를 들어, Hinderer 외. 및 Eoh 외. 전단 흐름, 3D 스캐폴드 미세 구조 이외에, 체외 모델시스템(24,25)에서인체 혈관 평활근 세포에 의한 성숙한 엘라스틴형성에 중요했다. 전부, 이 사실 인정은 심장 혈관 TE를 위한 순환 스트레칭 및 전단 긴장 둘 다의 관련성을 보여줍니다.
TE 임플란트의 성공 또는 실패에 대한 또 다른 중요한 결정요인은 이식된접목(26)에대한 호스트의 면역 반응이다. 이는 실제로 세포 유입 및 내인성 조직 형성 및 리모델링27의후속 과정을 킥스타트하기 위해 스캐폴드에 대한 급성 염증 반응에 의존하는 시투 TE 전략에서 물질 중심의 물질 중심의 물질 중심을 위해 특히 중요하다. 대식세포는 기능성 조직 재생의 중요한 시노레이터이며, 이는 다중 연구28,29,30에의해 나타났다. 상처 치유와 유사하게, 조직의 재생은 섬유아세포와 근섬유세포 와 같은 대식세포와 조직 생성 세포 사이의 파라크리노 신호에 의해 지배된다31,32,33. 새로운 조직 증착을 조정하는 것 외에도, 대식세포는이물질(34,35)의활성 재흡수에 관여한다. 이와 같이, 생체물질에 대한 체외 대식세포반응은임플란트(36,37,38)의생체 내 성공을 위한 예측 파라미터로서 확인되었다.
이식된 스캐폴드에 대한 대식대식 반응은 재료 조성 및미세구조(35,39,40)와같은 스캐폴드 설계 기능에 의존한다. 스캐폴드 특성 외에도 비계에 대한 대식대식 반응과 근섬유아세포와의 교차토크도 혈역학적 하중의 영향을 받았습니다. 예를 들어, 순환 스트레치는 대식세포 표현형41,42,43,44 및 사이토카인의 분비(43,44,45,46in 3D 일렉트로스펀 스캐폴드)의 중요한 변조기로 나타났다. 대식세포와 혈관 평활근 세포의 공동 배양 시스템을 사용하여, Battiston 등. 대식세포의 존재는 엘라스틴과 GAGs의 증가 수준으로 이어졌고 순환 스트레치 (1.07-1.10)의 적당한 수준이 콜라겐 I와 엘라스틴47의증착을 자극했다는 것을 입증했습니다. 전작에서는 전단 응력이 3D 전두엽 비계48,49로단백세포 모집을 위한 중요한 결정제이며, 전단 응력과 순환 스트레치 모두 인간 단세포와 중간엽 기질세포(50)사이의 파라크리온 신호에 영향을 미친다는 것을 입증하였다. Fahy 등은 전단 흐름이 인간단핵구(51)에의한 염증성 사이토카인의 분비를 증가시키는 것을 입증했다.
종합하면, 위의 증거는 혈역학 적재에 대한 적절한 이해와 제어가 심혈관 TE에 매우 중요하며 이를 달성하기 위해 염증 반응을 고려하는 것이 중요하다는 것을 보여줍니다. 수많은 생물 반응기는 이전에 시험관 내52,53,54,55, 56,57,57,58 또는 전 생체59,60,61 심혈관 조직의 문화를 위해 이전에 기술되었다. 그러나 이러한 모든 시스템은 가능한 한 생리적 혈역학 적재 조건을 모방하도록 설계되었습니다. 이것은 시험관 내에서 심장 혈관 조직을 만들거나 전 생체 문화를 유지하기위한 목적으로 매우 가치가 있지만, 이러한 시스템은 개별 단서의 개별 효과에 체계적인 연구를 허용하지 않습니다. 이는 이러한 생물 반응기에서 순환 스트레칭과 전단 응력의 적용이 본질적으로 연결되는 동일한 가압 흐름에 의해 구동되므로. 정확한 멀티큐 기계식 조작을 허용하는 마이크로시스템은 2D 기판62 또는 3D 하이드로겔 설정63,64에대해 설명되어 왔지만, 이러한 설정은 탄성액 3D 생물재료 스캐폴드의 통합을 허용하지 않는다.
여기에서, 우리는 유일하게 전단 응력과 순환 스트레칭의 분리를 가능하게하고 기계적으로 그들의 개별및 결합된 효력을 조사하는 것을 돕는 관 생물 반응기 시스템의 응용을 제시합니다. 이 시스템은 조직 설계 혈관 이식의 광범위한 테스트를 허용 (예를 들어, 합성 또는 자연 기원, 다른 마이크로 아키텍처, 다양한 다공성). 전단 응력과 스트레치의 적용을 효과적으로 분리하기 위해, 생체 반응기에서 사용하는 주요 개념은 (1) 뚜렷한 펌프 시스템을 사용하여 전단 응력 및 스트레치 제어의 분리와 (2) 스캐폴드의 자극을 계산 구동 치수로 '내부 아웃'방식으로 분리하는 것이다. 흐름은 유동 펌프의 사용을 통해 관 비계의 외부 표면에 적용되는 반면, 스캐폴드의 일주 스트레칭은 별도의 스트레인 펌프를 사용하여 스캐폴드가 장착되는 실리콘 튜브를 확장하여 유도된다. 구성을 포함하는 실리콘 튜브및 유리 튜브의 치수는 스캐폴드(흐름에 의한) 및 외주 스트레치(튜브 팽창로 인한)의 전단 응력이 서로 크게 영향을 미치지 않도록 하기 위해 전산 유체 역학 시뮬레이션을 사용하여 신중하게 선택및 검증된다. 이 내부 아웃 디자인은 몇 가지 실용적인 근거가 있습니다. 발광 유체 압력(생리적 적재와 유사)에 의해 스트레치가 적용되는 경우, 본질적으로 샘플 설계가 누출되지 않습니다. 또한, 시료를 스트레칭하는 데 필요한 압력은 시료 강성에 의해 완전히 결정되며, 이는 시간이 지남에 따라 샘플과 샘플 내에서 다를 수 있어 스트레치를 제어하기가 어려워집니다. 이 생물 반응기는 실리콘 튜브 주위에 조직 설계 이식편을 장착하고 접목의 외벽에 벽 전단 응력 (WSS) 응용 프로그램을 허용하고 내부에서 접목을 가압합니다. 이러한 방식으로, 시간이 지남에 따라 샘플과 샘플 내의 동일한 하중 조건을 보장할 수 있으며, 또한, 다공성 혈관비계(19)에공통적으로 도공되는 바와 같이 시료가 새는 것을 허용한다. 이 내부 아웃 생물 반응기는 특히 전통적인 혈관 생물 반응기 설치가 더 적합한 시험관 내의 토착 혈관의 엔지니어링보다는 전단 및 / 또는 스트레치의 효과에 대한 체계적인 연구를 위한 것입니다. 생물 반응기 설계 도면에대한 그림 1A-B를 참조하고, 생체 반응기의 주요 구성 요소 뒤에 기능적 설명 및 근거에 대한 해당 표 1을 참조하십시오.
생물 반응기의 사용은 우리가 시상 심혈 관 조직19,43,44에대한 반사 전기 스프폴드에서 염증과 조직 형성에 전단 스트레스와 순환 스트레칭의 개인 및 결합 된 영향을 조사하는 우리 그룹에 의해 최근 연구의 시리즈에 기초하여 입증된다. 이를 위해, 우리는 인간 대식세포와 근섬유아세포를 모노 또는 공동 배양에서 사용하여 시투 재생 폭포의 다양한 단계를 시뮬레이션했습니다. 우리는 인간 대식세포에 의한 사이토카인 분비액이 이러한 비계에서 인간 근섬유세포에 의해 매트릭스 증착 및 조직에 영향을 미치는 순환 스트레치 및 전단 응력 모두에 의해 뚜렷하게 영향을 받는것을 입증했으며, 파라크리노 신호 및 직접 접촉19,43,44를통해. 특히, 이러한 연구는 전단 스트레스와 스트레칭의 결합 된 응용 프로그램의 경우, 조직 형성과 염증에 미치는 영향은 두 부하 중 하나에 의해 지배된다는 것을 밝혔다, 또는 두 부하의 시너지 효과가있다. 이러한 연구 결과는 TE 공정에서 기계적 환경의 기여를 더 잘 이해하기 위해 두 부하를 분리하는 관련성을 보여줍니다. 이러한 이해는 관련 혈역학 적재 기조에서 스캐폴드 설계 파라미터를 체계적으로 최적화하기 위해 적용될 수 있습니다. 또한, 이러한 잘 조절된 환경에서 의 기계형 데이터는 최근 TEVGs65 또는 TEHV66에대해 보고된 바와 같이, 시투 조직 리모델링 과정을 예측하기 위해 개발되고 있는 수치 모델에 대한 입력으로 작용할 수 있으며, 예측 능력을 더욱 향상시킨다.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr >
			<td >advanced Dulbecco&#8217;s modified EagleMedium (aDMEM)</td>
			<td >Gibco</td>
			<td >12491-015</td>
			<td >cell culture medium for fibroblasts</td>
		</tr>
		<tr >
			<td >Aqua Stabil</td>
			<td >Julabo</td>
			<td >8940012</td>
			<td >prevent microorganism growth in bioreactor-hydraulic reservoir</td>
		</tr>
		<tr >
			<td >Bovine fibrinogen</td>
			<td >Sigma</td>
			<td >F8630</td>
			<td >to prepare fibrinogen gel to seed the cells on the electrospun scaffold</td>
		</tr>
		<tr >
			<td >Bovine thrombin</td>
			<td >Sigma</td>
			<td >T4648</td>
			<td >to prepare fibrinogen gel to seed the cells on the electrospun scaffold</td>
		</tr>
		<tr >
			<td >Centrifuge</td>
			<td >Eppendorf</td>
			<td >5804</td>
			<td >to spin down cells and conditioned medium</td>
		</tr>
		<tr >
			<td >Clamp scissor - &#34;kelly forceps&#34;</td>
			<td >Almedic</td>
			<td >P-422</td>
			<td >clamp the silicone tubing and apply pre-stretch to the scaffold so the scaffold can be sutured into the engraved groove (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >CO2 cell culture incubators</td>
			<td >Sanyo</td>
			<td >MCO-170AIC-PE</td>
			<td >for cell culturing</td>
		</tr>
		<tr >
			<td >Compressed air reservoir</td>
			<td >Festo</td>
			<td >CRVZS-5</td>
			<td >smoothing air pressure fluctuations and create time delays for pressure build-up</td>
		</tr>
		<tr >
			<td >Custom Matlab script to calculate the maximum stretches</td>
			<td >Matlab</td>
			<td >R2017. The Mathworks, Natick, MA</td>
			<td >calculate the minimum and maximum outer diameter of the electrospun scaffold</td>
		</tr>
		<tr >
			<td >Data acquisition board</td>
			<td >National Instruments</td>
			<td >BNC-2090</td>
			<td >data processing in between amplifier system and computer</td>
		</tr>
		<tr >
			<td >Ethanol</td>
			<td >VWR</td>
			<td >VWRK4096-9005</td>
			<td >to keep sterile working conditions</td>
		</tr>
		<tr >
			<td >Fetal bovine calf serum (FBS)</td>
			<td >Greiner</td>
			<td >758087</td>
			<td >cell culture medium supplement; serum-supplement</td>
		</tr>
		<tr >
			<td >Flow culture chamber compartments, consisting of a pressure conduit with engraved grooves and small holes to apply pressure on silicone tubing, a screw thread, nose cone, top compartment with flow inlet and bottom compartment flow outlet, adapter bushing</td>
			<td >Custom made, Department of Biomedical Engineering, Eindhoven University of Technology</td>
			<td >n.a.</td>
			<td >flow culture chamber compartments (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Glass Pasteur pipet</td>
			<td >Assistant</td>
			<td >HE40567002</td>
			<td >apply vacuum on electrospun scaffold (autoclave at step 1)</td>
		</tr>
		<tr >
			<td >Glass tubes of the flow culture chamber</td>
			<td >Custon made, Equipment &#38; Prototype Center, Eindhoven University of Technology</td>
			<td >n.a.</td>
			<td >part of the flow culture chamber (clean and store in 70% ethanol, at step 1 and 7)</td>
		</tr>
		<tr >
			<td >GlutaMax</td>
			<td >Gibco</td>
			<td >35050061</td>
			<td >cell culture medium amino acid supplement, minimizes ammonia build-up</td>
		</tr>
		<tr >
			<td >High speed camera</td>
			<td >MotionScope</td>
			<td >M-5</td>
			<td >to monitor the stretch during culture; time-lapse photographs of the scaffolds are captured at a frequency of 30 Hz for 6 sec (i.e. 3 stretch cycles)</td>
		</tr>
		<tr >
			<td >High speed camera lens - Micro-NIKKOR 55mm f/2.8 - lens</td>
			<td >Nikon</td>
			<td >JAA616AB</td>
			<td >to monitor the stretch during culture; time-lapse photographs of the scaffolds are captured at a frequency of 30 Hz for 6 sec (i.e. 3 stretch cycles)</td>
		</tr>
		<tr >
			<td >Hose clip</td>
			<td >ibidi GmbH</td>
			<td >10821</td>
			<td >block medium flow (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Hydraulic reservoir with 8 screw threads for 8 flow culture chambers</td>
			<td >Custom made, Department of Biomedical Engineering, Eindhoven University of Technology</td>
			<td >n.a.</td>
			<td >to apply pressure to the silicone mounted constructs (clean outside with a paper tissue with 70% ethanol, rinse reservoir with 70% ethanol followed by demi water, at step 1 and 7)</td>
		</tr>
		<tr >
			<td >Ibidi pump system (8x) including ibidi pump, PumpControl software, fluidic unit, perfusion set (medium tubing), air pressure tubing, drying bottles with orange silica beads</td>
			<td >ibidi GmbH</td>
			<td >10902</td>
			<td >set up used to control the flow in the flow culture chambers. Note 1: the ibidi pumps were modified by the manufacturer to enable 200 mbar capacity. Note 2: can be replaced by pump system of other manufacturer, as long as same flow regimes can be applied.</td>
		</tr>
		<tr >
			<td >Knives (no.10 sterile blades, individual foil pack) and scalpel handle (stainless steel, individually wrapped)</td>
			<td >Swann Morton</td>
			<td >0301; 0933</td>
			<td >to cut the silicone tubing in the correct size for the scaffold and to cut the suture material</td>
		</tr>
		<tr >
			<td >LabVIEW Software</td>
			<td >National Instruments</td>
			<td >version 2018</td>
			<td >to control the stretch applied to the scaffolds</td>
		</tr>
		<tr >
			<td >Laminar flow biosafety cabinet with UV light</td>
			<td >Labconco</td>
			<td >302310001</td>
			<td >to ensure sterile working conditions. The UV is used to decontaminate everything that cannot be autoclaved, or touched after autoclaving</td>
		</tr>
		<tr >
			<td >Large and small petri dishes</td>
			<td >Greiner</td>
			<td >664-160</td>
			<td >for sterile working conditions</td>
		</tr>
		<tr >
			<td >L-ascorbic acid 2-phosphate (vitamin C)</td>
			<td >Sigma</td>
			<td >A8960</td>
			<td >cell culture medium supplement, important for collagen production</td>
		</tr>
		<tr >
			<td >LED light cold source KL2500</td>
			<td >Zeiss</td>
			<td >Schott AG</td>
			<td >to aid in visualization for the time lapse of the scaffolds during monitoring of the stretch</td>
		</tr>
		<tr >
			<td >Luer (female and male) locks and connectors, white luer caps</td>
			<td >ibidi GmbH</td>
			<td >various, see (https://ibidi.com/26-flow-accessories)</td>
			<td >to close or connect parts of the bioreactor and the ibidi pump (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Measuring amplifier (PICAS)</td>
			<td >PEEKEL instruments B.V.</td>
			<td >n.a.</td>
			<td >to amplify the signal from the pressure sensor and feedback to LabView</td>
		</tr>
		<tr >
			<td >Medium reservoir (large syringes 60 mL) and reservoir holders</td>
			<td >ibidi GmbH</td>
			<td >10974</td>
			<td >medium reservoir (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Medium tubing with 4.25 mm outer diameter and 1 mm inner diameter</td>
			<td >Rubber BV</td>
			<td >1805</td>
			<td >to allow for a larger flow rate, the ibidi medium tubing with larger diameter is used. Note: the part of medium tubing guided through the fluidic unit valves are the same as the default ibidi medium tubing</td>
		</tr>
		<tr >
			<td >Motion Studio Software</td>
			<td >Idtvision</td>
			<td >2.15.00</td>
			<td >to make the high speed time lapse images for stretch monitoring</td>
		</tr>
		<tr >
			<td >Needle (19G)</td>
			<td >BD Microlance</td>
			<td >301700</td>
			<td >together with thin flexible tubing used to fill the hydraulic reservoir with ultrapure water without adding air bubbles</td>
		</tr>
		<tr >
			<td >Needle driver</td>
			<td >Adson</td>
			<td >2429218</td>
			<td >to handle the needle of the nylon suture through the silicone tube (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Paper tissues</td>
			<td >Kleenex</td>
			<td >38044001</td>
			<td >for cleaning of the equipment with 70% ethanol</td>
		</tr>
		<tr >
			<td >Parafilm</td>
			<td >Sigma</td>
			<td >P7793-1EA</td>
			<td >quick fix if leakage occurs</td>
		</tr>
		<tr >
			<td >Penicillin/streptomycin (P/S)</td>
			<td >Lonza</td>
			<td >DE17-602E</td>
			<td >cell culture medium supplement; prevent bacterial contamination</td>
		</tr>
		<tr >
			<td >Phosphate Buffered Saline (PBS)</td>
			<td >Sigma</td>
			<td >P4417-100TAB</td>
			<td >for storage and washing steps (autoclave at step 1)</td>
		</tr>
		<tr >
			<td >Plastic containers (60 mL) with red screw caps</td>
			<td >Greiner</td>
			<td >206202</td>
			<td >to prepare the fibrinogen solution</td>
		</tr>
		<tr >
			<td >Pneumatic cylinder</td>
			<td >Festo</td>
			<td >AEVC-20-10-I-P</td>
			<td >to actuate the Teflon bellow (clean with a paper tissue with 70% ethanol at step 1 and 7)</td>
		</tr>
		<tr >
			<td >Polycaprolactone bisurea (PCL-BU) tubular scaffolds (3 mm inner diameter, 200 &#181;m wall thickness, 20 mm length)</td>
			<td >SyMO-Chem, Eindhoven, The Netherlands</td>
			<td >n.a.</td>
			<td >produced using electrospinning from 15% (w/w) chloroform (Sigma; 372978) polymer solutions. See Van Haaften et al Tissue Engineering Part C (2018) for more details</td>
		</tr>
		<tr >
			<td >Pressure conduit without holes (for static control)</td>
			<td >Custom made, Department of Biomedical Engineering, Eindhoven University of Technology</td>
			<td >n.a.</td>
			<td >to mount electrospun tubes on silicon tubing (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Pressure sensor and transducer</td>
			<td >BD</td>
			<td >TC-XX and P 10 EZ</td>
			<td >the air pressure going to the pneumatic actuated pump is raised until it reaches the set pressure</td>
		</tr>
		<tr >
			<td >Proportional air pressure control valve and pressure sensor</td>
			<td >Festo</td>
			<td >MPPES-3-1/8-2-010, 159596</td>
			<td >provides compressed air to the pneumatic actuated pump</td>
		</tr>
		<tr >
			<td >Roswell Park Memorial Institute 1640 (RPMI-1640)</td>
			<td >Gibco</td>
			<td >A1049101</td>
			<td >cell culture medium for monocyte/macrophage</td>
		</tr>
		<tr >
			<td >Safe lock Eppendorf tubes (1.5 mL)</td>
			<td >Eppendorf</td>
			<td >30120086</td>
			<td >multiple applications (autoclave at step 1)</td>
		</tr>
		<tr >
			<td >Sodium dodecyl sulfate solution 20%</td>
			<td >Sigma</td>
			<td >5030</td>
			<td >Used to clean materials, at a concentration of 0.1%.&#160;&#160;</td>
		</tr>
		<tr >
			<td >Silicone O-rings</td>
			<td >Technirub</td>
			<td >1250S</td>
			<td >to prevent leakage (autoclave at step 1, step 7)</td>
		</tr>
		<tr >
			<td >Silicone tubing (2.8 mm outer diameter, 400 um wall thickness)</td>
			<td >Rubber BV</td>
			<td >1805</td>
			<td >to mount the electrospun tubes on the pressure conduits (autoclave at step 1)</td>
		</tr>
		<tr >
			<td >Sterile tube (15 mL)</td>
			<td >Falcon</td>
			<td >352095</td>
			<td >multiple applications</td>
		</tr>
		<tr >
			<td >Suture, 5-0 prolene with pre-attached taper point needle</td>
			<td >Ethicon, Johnson&#38;Johnson</td>
			<td >EH7404H</td>
			<td >Prolene suture wire 5-0 (75cm length, TF taper point needle, 1/2 circle, 13 mm needle length)</td>
		</tr>
		<tr >
			<td >Syringe (24 mL)</td>
			<td >B. Braun Melsungen AG</td>
			<td >2057932</td>
			<td >to add the ultrapure water or medium to the hydraulic reservoir or flow culture chamber</td>
		</tr>
		<tr >
			<td >Syringe filter (0.2 &#181;m)</td>
			<td >Satorius</td>
			<td >17597-K</td>
			<td >to filter the fibrinogen solution</td>
		</tr>
		<tr >
			<td >T150 cell culture flask with filter cap</td>
			<td >Nunc</td>
			<td >178983</td>
			<td >to degas culture medium</td>
		</tr>
		<tr >
			<td >T75 Cell culture flask with filter cap</td>
			<td >Nunc</td>
			<td >156499</td>
			<td >to culture static control samples</td>
		</tr>
		<tr >
			<td >Teflon bellow</td>
			<td >Custom made, Department of Biomedical Engineering, Eindhoven University of Technology</td>
			<td >n.a.</td>
			<td >to load the hydraulic reservoir (clean outside with a paper tissue with 70% ethanol at step 1 and 7)</td>
		</tr>
		<tr >
			<td >Tray (stainless steel)</td>
			<td >PolarWare</td>
			<td >15-248</td>
			<td >for easy transport of the fluidic culture chambers and the bioreactor from incubator to laminar flow cabinet and back (clean with a paper tissue with 70% ethanol before and after use)</td>
		</tr>
		<tr >
			<td >Tweezers</td>
			<td >Wironit</td>
			<td >4910</td>
			<td >sterile handling of individual parts (autoclave at step 1 and 7)</td>
		</tr>
		<tr >
			<td >Ultrapure water</td>
			<td >Stakpure</td>
			<td >Omniapure UV 18200002</td>
			<td >to correct for medium evaporation, mixed with aqua stabil mixed and used as hydraulic fluid. (autoclave ultrapure water at step 1)</td>
		</tr>
		<tr >
			<td >UV light</td>
			<td >Philips</td>
			<td >TUV 30W/G30 T8</td>
			<td >for decontamination of grafts and bioreactor parts before seeding</td>
		</tr>
	</tbody>
</table>

a multi-cue bioreactor to evaluate the inflammatory and regenerative capacity of biomaterials under flow and stretch

신체에서 직접 재생을 유도하는 재생을 유도하는 재생 가능한 생체 재료의 사용은 번역 관점에서 매력적인 전략입니다. 이러한 물질은 이식 시 염증 반응을 유도하며, 이는 물질의 후속 흡수와 새로운 조직의 재생의 원동력이다. 이 전략, 또한 시투 조직 공학에서 로 알려진, 조직 설계 혈관 이식 등 심장 혈관 교체를 얻기 위해 추구. 염증 및 재생 공정 은 스캐폴드 (즉, 스트레치 및 전단 응력)에 대한 국소 생체 역학 적 단서에 의해 결정됩니다. 여기서는 관 비계에서 스트레치및 전단 응력을 분리할 수 있는 맞춤형 생물 반응기의 사용을 자세히 설명합니다. 이를 통해 인간 대식세포와 근섬유아세포아제를 이용한 역동적인 공동배양 실험에 기초하여 입증되는 잘 조절된 기계적 하중의 영향으로 관 비계의 염증및 재생 능력의 체계적이고 표준화된 평가를 가능하게 한다. 바이오 반응기의 구성 및 설정, 비계 및 세포 파종의 준비, 스트레치 및 전단 흐름의 적용 및 유지 보수, 분석을 위한 샘플 수확 등 이 접근법의 주요 실용적인 단계는 자세히 설명합니다.

이 생물 반응기는 혈관 조직 성장에 전단 스트레스와 순환 스트레칭의 개별적이고 결합 된 효과를 연구하고 3D 생체 물질 스캐폴드에서 리모델링하기 위해 개발되었다. 생물 반응기의 설계는 다양한 적재 조건하에서 최대 8개의 혈관 구조를 배양할 수 있게한다(도 1A). 혈관 구조는 둘레 스트레치와 WSS가 독립적으로 제어될 수 있는 유량 배양챔버(도 1B)에</stron...

Watch this Scientific Journal Video about A Multi-Cue Bioreactor to Evaluate the Inflammatory and Regenerative Capacity of Biomaterials under Flow and Stretch at JoVE.com

A Multi-Cue Bioreactor to Evaluate the Inflammatory and Regenerative Capacity of Biomaterials under Flow and Stretch

이 프로토콜의 목표는 관형 전기 스캐폴드에서 인간 대식세포와 근섬유세포의 동적 공동 배양을 실행하여 재료 중심 조직 재생을 조사하는 것이며, 전단 응력과 순환 스트레칭의 분리를 가능하게 하는 생체 반응기를 사용하는 것입니다.

유량 및 스트레치 하에서 생체 재료의 염증 및 재생 능력을 평가하는 다중 큐 생물 반응기

The use of resorbable biomaterials to induce regeneration directly in the body is an attractive strategy from a translational perspective. Such materials ...

a-multi-cue-bioreactor-to-evaluate-inflammatory-regenerative-capacity

Research

JoVE Journal

Engineering

5.4K 조회수.  Eindhoven University of Technology. 이 프로토콜의 목표는 관형 전기 스캐폴드에서 인간 대식세포와 근섬유세포의 동적 공동 배양을 실행하여 재료 중심 조직 재생을 조사하는 것이며, 전단 응력과 순환 스트레칭의 분리를 가능하게 하는 생체 반응기를 사용하는 것입니다.

비디오: A Multi-Cue Bioreactor to Evaluate the Inflammatory and Regenerative Capacity of Biomaterials under Flow and Stretch

Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is presented. The SANS shear cell consists of a concentric cylinder Couette geometry that is sealed and rotating about a horizontal axis so that the vorticity direction of the flow field is aligned with the neutron beam enabling scattering from the 1-2 plane of shear (velocity-velocity gradient, respectively). This approach is an advance over previous shear cell sample environments as there is a strong coupling between the bulk rheology and microstructural features in the 1-2 plane of shear. Flow-instabilities, such as shear banding, can also be studied by spatially resolved measurements. This is accomplished in this sample environment by using a narrow aperture for the neutron beam and scanning along the velocity gradient direction. Time resolved experiments, such as flow start-ups and large amplitude oscillatory shear flow are also possible by synchronization of the shear motion and time-resolved detection of scattered neutrons. Representative results using the methods outlined here demonstrate the useful nature of spatial resolution for measuring the microstructure of a wormlike micelle solution that exhibits shear banding, a phenomenon that can only be investigated by resolving the structure along the velocity gradient direction. Finally, potential improvements to the current design are discussed along with suggestions for supplementary experiments as motivation for future experiments on a broad range of complex fluids in a variety of shear motions.

A shear cell is developed for small-angle neutron scattering measurements in the velocity-velocity gradient plane of shear and is used to characterize complex fluids. Spatially resolved measurements in the velocity gradient direction are possible for studying shear-banding materials. Applications include investigations of colloidal dispersions, polymer solutions, and self-assembled structures.

1-2 평면 흐름 - 작은 각 중성자 산란을 이용하여 재료 미세 조직에서 유량을 측정

A new small-angle neutron scattering (SANS) sample environment optimized for studying the microstructure of complex fluids under simple shear flow is ...

연구

공학

Experimental Protocol to Investigate Particle Aerosolization of a Product Under Abrasion and Under Environmental Weathering

The present article presents an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental weathering, which is a fundamental element to the approach of nanosafety-by-design of nanostructured products for their durable development. This approach is basically a preemptive one in which the focus is put on minimizing the emission of engineered nanomaterials' aerosols during the usage phase of the product's life cycle. This can be attained by altering its material properties during its design phase without compromising with any of its added benefits. In this article, an experimental protocol is presented to investigate the nanosafety-by-design of three commercial nanostructured products with respect to their mechanical solicitation and environmental weathering. The means chosen for applying the mechanical solicitation is an abrasion process and for the environmental weathering, it is an accelerated UV exposure in the presence of humidity and heat. The eventual emission of engineered nanomaterials is studied in terms of their number concentration, size distribution, morphology and chemical composition. The purpose of the protocol is to study the emission for test samples and experimental conditions which are corresponding to real life situations. It was found that the application of the mechanical stresses alone emits the engineered nanomaterials' aerosols in which the engineered nanomaterial is always embedded inside the product matrix, thus, a representative product element. In such a case, the emitted aerosols comprise of both nanoparticles as well as microparticles. But if the mechanical stresses are coupled with the environmental weathering, the experimental protocol reveals then the eventual deterioration of the product, after a certain weathering duration, may lead to the emission of the free engineered nanomaterial aerosols too.

In this article, an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental weathering is presented. Results on the emission of engineered nanomaterials, in the form of aerosols are presented. The specific experimental set-up is described in detail.

실험 프로토콜 마모에서 환경 풍화에서 제품의 입자 에어로졸을 조사하기

The present article presents an experimental protocol to investigate particle aerosolization of a product under abrasion and under environmental ...

Design and Use of a Full Flow Sampling System (FFS) for the Quantification of Methane Emissions

The use of natural gas continues to grow with increased discovery and production of unconventional shale resources. At the same time, the natural gas industry faces continued scrutiny for methane emissions from across the supply chain, due to methane&#39;s relatively high global warming potential (25-84x that of carbon dioxide, according to the Energy Information Administration). Currently, a variety of techniques of varied uncertainties exists to measure or estimate methane emissions from components or facilities. Currently, only one commercial system is available for quantification of component level emissions and recent reports have highlighted its weaknesses.
In order to improve accuracy and increase measurement flexibility, we have designed, developed, and implemented a novel full flow sampling system (FFS) for quantification of methane emissions and greenhouse gases based on transportation emissions measurement principles. The FFS is a modular system that consists of an explosive-proof blower(s), mass airflow sensor(s) (MAF), thermocouple, sample probe, constant volume sampling pump, laser based greenhouse gas sensor, data acquisition device, and analysis software. Dependent upon the blower and hose configuration employed, the current FFS is able to achieve a flow rate ranging from 40 to 1,500 standard cubic feet per minute (SCFM). Utilization of laser-based sensors mitigates interference from higher hydrocarbons (C2+). Co-measurement of water vapor allows for humidity correction. The system is portable, with multiple configurations for a variety of applications ranging from being carried by a person to being mounted in a hand drawn cart, on-road vehicle bed, or from the bed of utility terrain vehicles (UTVs). The FFS is able to quantify methane emission rates with a relative uncertainty of &#177; 4.4%. The FFS has proven, real world operation for the quantification of methane emissions occurring in conventional and remote facilities.

Design and Use of a Full Flow Sampling System FFS for the Quantification of Methane Emissions

We have designed, developed, and implemented a novel full flow sampling system (FFS) for quantification of methane emissions and greenhouse gases from across the natural gas supply chain.

메탄 배출량의 정량화를위한​​ 설계 및 전체 흐름 샘플링 시스템 (FFS)의 사용

The use of natural gas continues to grow with increased discovery and production of unconventional shale resources. At the same time, the natural gas ...

A Robotic Platform to Study the Foreflipper of the California Sea Lion

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most of their thrust with their large foreflippers. This protocol describes a robotic platform designed to study the hydrodynamic performance of the swimming California sea lion (Zalophus californianus). The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;). The kinematics of the sea lion&#39;s propulsive stroke are extracted from video data of unmarked, non-research sea lions at the Smithsonian Zoological Park (SNZ). Those data form the basis of the actuation motion of the robotic flipper presented here. The geometry of the robotic flipper is based a on high-resolution laser scan of a foreflipper of an adult female sea lion, scaled to about 60% of the full-scale flipper. The articulated model has three joints, mimicking the elbow, wrist and knuckle joint of the sea lion foreflipper. The robotic platform matches dynamics properties&#8212;Reynolds number and tip speed&#8212;of the animal when accelerating from rest. The robotic flipper can be used to determine the performance (forces and torques) and resulting flowfields.

A robotic platform is described that will be used to study the hydrodynamic performance&#8212;forces and flowfields&#8212;of the swimming California sea lion. The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;).

로봇 플랫폼은 캘리포니아 바다 사자의 Foreflipper를 공부하기

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most ...

Solvent Bonding for Fabrication of PMMA and COP Microfluidic Devices

Thermoplastic microfluidic devices offer many advantages over those made from silicone elastomers, but bonding procedures must be developed for each thermoplastic of interest. Solvent bonding is a simple and versatile method that can be used to fabricate devices from a variety of plastics. An appropriate solvent is added between two device layers to be bonded, and heat and pressure are applied to the device to facilitate the bonding. By using an appropriate combination of solvent, plastic, heat, and pressure, the device can be sealed with a high quality bond, characterized as having high bond coverage, bond strength, optical clarity, durability over time, and low deformation or damage to microfeature geometry. We describe the procedure for bonding devices made from two popular thermoplastics, poly(methyl-methacrylate) (PMMA), and cyclo-olefin polymer (COP), as well as a variety of methods to characterize the quality of the resulting bonds, and strategies to troubleshoot low quality bonds. These methods can be used to develop new solvent bonding protocols for other plastic-solvent systems.

Solvent bonding is a simple and versatile method for fabricating thermoplastic microfluidic devices with high quality bonds. We describe a protocol to achieve strong, optically clear bonds in PMMA and COP microfluidic devices that preserve microfeature details, by a judicious combination of pressure, temperature, an appropriate solvent, and device geometry.

PMMA의 제조 및 COP 미세 유체 장치에 대한 솔벤트 본딩

Thermoplastic microfluidic devices offer many advantages over those made from silicone elastomers, but bonding procedures must be developed for each ...

In Situ Visualization of the Phase Behavior of Oil Samples Under Refinery Process Conditions

To help address production issues in refineries caused by the fouling of process units and lines, we have developed a setup as well as a method to visualize the behavior of petroleum samples under process conditions. The experimental setup relies on a custom-built micro-reactor fitted with a sapphire window at the bottom, which is placed over the objective of an inverted microscope equipped with a cross-polarizer module. Using reflection microscopy enables the visualization of opaque samples, such as petroleum vacuum residues, or asphaltenes. The combination of the sapphire window from the micro-reactor with the cross-polarizer module of the microscope on the light path allows high-contrast imaging of isotropic and anisotropic media. While observations are carried out, the micro-reactor can be heated to the temperature range of cracking reactions (up to 450 &#176;C), can be subjected to H2 pressure relevant to hydroconversion reactions (up to 16 MPa), and can stir the sample by magnetic coupling. 
Observations are typically carried out by taking snapshots of the sample under cross-polarized light at regular time intervals. Image analyses may not only provide information on the temperature, pressure, and reactive conditions yielding phase separation, but may also give an estimate of the evolution of the chemical (absorption/reflection spectra) and physical (refractive index) properties of the sample before the onset of phase separation.

In Situ Visualization of the Phase Behavior of Oil Samples Under Refinery Process Conditions

This article describes a setup and method for the in situ visualization of oil samples under a variety of temperature and pressure conditions that aim to emulate refining and upgrading processes. It is primarily used for studying isotropic and anisotropic media involved in the fouling behavior of petroleum feeds.

정유 공정 조건에서 오일 샘플의 위상 행동 제자리 시각화에서

To help address production issues in refineries caused by the fouling of process units and lines, we have developed a setup as well as a method to ...

A Novel Biaxial Testing Apparatus for the Determination of Forming Limit under Hot Stamping Conditions

The hot stamping and cold die quenching process is increasingly used to form complex shaped structural components of sheet metals. Conventional experimental approaches, such as out-of-plane and in-plane tests, are not applicable to the determination of forming limits when heating and rapid cooling processes are introduced prior to forming for tests conducted under hot stamping conditions. A novel in-plane biaxial testing system was designed and used for the determination of forming limits of sheet metals at various strain paths, temperatures, and strain rates after heating and cooling processes in a resistance heating uniaxial testing machine. The core part of the biaxial testing system is a biaxial apparatus, which transfers a uniaxial force provided by the uniaxial testing machine to a biaxial force. One type of cruciform specimen was designed and verified for the formability test of aluminum alloy 6082 using the proposed biaxial testing system. The digital image correlation (DIC) system with a high-speed camera was used for taking strain measurements of a specimen during a deformation. The aim of proposing this biaxial testing system is to enable the forming limits of an alloy to be determined at various temperatures and strain rates under hot stamping conditions.

This protocol proposes a novel biaxial testing system used on a resistance heating uniaxial tensile test machine in order to determine the forming limit diagram (FLD) of sheet metals under hot stamping conditions.

The hot stamping and cold die quenching process is increasingly used to form complex shaped structural components of sheet metals. Conventional ...

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy (ATOM)

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the main trend in the advanced development of flow cytometry. Notably, adding high-resolution imaging capabilities allows for the complex morphological analysis of cellular/sub-cellular structures. This is not possible with standard flow cytometers. However, it is valuable for advancing our knowledge of cellular functions and can benefit life science research, clinical diagnostics, and environmental monitoring. Incorporating imaging capabilities into flow cytometry compromises the assay throughput, primarily due to the limitations on speed and sensitivity in the camera technologies. To overcome this speed or throughput challenge facing imaging flow cytometry while preserving the image quality, asymmetric-detection time-stretch optical microscopy (ATOM) has been demonstrated to enable high-contrast, single-cell imaging with sub-cellular resolution, at an imaging throughput as high as 100,000 cells/s. Based on the imaging concept of conventional time-stretch imaging, which relies on all-optical image encoding and retrieval through the use of ultrafast broadband laser pulses, ATOM further advances imaging performance by enhancing the image contrast of unlabeled/unstained cells. This is achieved by accessing the phase-gradient information of the cells, which is spectrally encoded into single-shot broadband pulses. Hence, ATOM is particularly advantageous in high-throughput measurements of single-cell morphology and texture &#8211; information indicative of cell types, states, and even functions. Ultimately, this could become a powerful imaging flow cytometry platform for the biophysical phenotyping of cells, complementing the current state-of-the-art biochemical-marker-based cellular assay. This work describes a protocol to establish the key modules of an ATOM system (from optical frontend to data processing and visualization backend), as well as the workflow of imaging flow cytometry based on ATOM, using human cells and micro-algae as the examples.

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy ATOM

This protocol describes the implementation of an asymmetric-detection time-stretch optical microscopy system for single-cell imaging in ultrafast microfluidic flow and its applications in imaging flow cytometry.

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the ...

Flow-assisted Dielectrophoresis: A Low Cost Method for the Fabrication of High Performance Solution-processable Nanowire Devices

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of nanowires. DEP is used for nanowire analysis, characterization, and for solution-based fabrication of semiconducting devices. The method works by applying an alternating electric field between metallic electrodes. The nanowire formulation is then dropped onto the electrodes which are on an inclined surface to create a flow of the formulation using gravity. The nanowires then align along the gradient of the electric field and in the direction of the liquid flow. The frequency of the field can be adjusted to select nanowires with superior conductivity and lower trap density. 
In this work, flow-assisted DEP is used to create nanowire field effect transistors. Flow-assisted DEP has several advantages: it allows selection of nanowire electrical properties; control of nanowire length; placement of nanowires in specific areas; control of orientation of nanowires; and control of nanowire density in the device. 
The technique can be expanded to many other applications such as gas sensors and microwave switches. The technique is efficient, quick, reproducible, and it uses a minimal amount of dilute solution making it ideal for the testing of novel nanomaterials. Wafer scale assembly of nanowire devices can also be achieved using this technique, allowing large numbers of samples for testing and large-area electronic applications.

In this paper, flow assisted dielectrophoresis is demonstrated for the self-assembly of nanowire devices. The fabrication of a silicon nanowire field effect transistor is shown as an example.

흐름 기반 Dielectrophoresis: 고성능 솔루션 처리 나노와이어 소자의 제조에 대 한 낮은 비용 방법

Flow-assisted dielectrophoresis (DEP) is an efficient self-assembly method for the controllable and reproducible positioning, alignment, and selection of ...

Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing

This manuscript describes an experimental procedure that allows obtaining diverse quantitative information on temporal and spatial evolution of water waves excited by time-dependent and steady wind forcing. Capacitance-type wave gauge and Laser Slope Gauge (LSG) are used to measure instantaneous water surface elevation and two components of the instantaneous surface slope at a number of locations along the test section of a wind-wave facility. The computer-controlled blower provides airflow over the water in the tank whose rate can vary in time. In the present experiments, the wind speed in the test section initially increases quickly from rest to the set value. It is then kept constant for the prescribed duration; finally, the airflow is shut down. At the beginning of each experimental run, the water surface is calm and there is no wind. Operation of the blower is initiated simultaneously with the acquisition of data provided by all sensors by a computer; data acquisition continues until the waves in the tank fully decay. Multiple independent runs performed under identical forcing conditions allow determining statistically reliable ensemble-averaged characteristic parameters that quantitatively describe wind-waves&#39; variation in time for the initial development stage as a function of fetch. The procedure also allows characterizing the spatial evolution of the wave field under steady wind forcing, as well as decay of waves in time, once the wind is shut down, as a function of fetch.

This manuscript describes a fully computer-controlled procedure that allows obtaining reliable statistical parameters from experiments of water waves excited by steady and unsteady wind forcing in a small-scale facility.

This manuscript describes an experimental procedure that allows obtaining diverse quantitative information on temporal and spatial evolution of water ...