Name: ferromagnetic bare metal stent for endothelial cell capture and retention
Uploaded: 2015-09-18T15:00:00.000+00:00
Duration: 11 min 1 s
Description: Watch this Scientific Journal Video about Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention at JoVE.com

The authors thank Tyra Witt, Cheri Mueske, Brant Newman and Dr. Peter J. Psaltis, MBBS, PhD for their valuable contributions. This study was financially supported by European Regional Development Fund &#8211; FNUSA-ICRC (No. CZ.1.05/1.100/02.0123), American Heart Association Scientist Development Grant (AHA #06-35185N), National Institutes of Health (T32HL007111) and The Grainger Innovation Fund &#8211; Grainger Foundation.

모든 동물 실험은 메이요 클리닉에서 기관 동물 관리 및 이용위원회 (IACUC)에 의해 승인되었다. 2205 스테인레스 스틸 스텐트 1. 설계 및 분석 <ol><li> CAD를 사용하여 베어 메탈 스텐트 설계 <ol><li> 스텐트 스트럿 두께와 같은 벽 두께와 &#39;돌출 보스 /베이스&#39;기능을 선택하여 압출 중공 실린더를 확인합니다. </li><li> 압출 실린더 접선 다른 스케치 평면에 스텐트 패턴을 디자인합니다. 압출 중공 원통의 원주에 일치하도록 평면 패턴의 폭을 만든다. </li><li> 랩 기능을 사용하여 중공 실린더에 플랫 패턴 디자인을 전송합니다. </li><li> 네이티브 형식으로도 FEA에 대한 수출 될 ACIS 형식으로 파트를 저장합니다. </li></ol></li><li> 스텐트 모델의 유한 요소 해석 <ol><li> 더 분​​석가에 대한 유한 요소 해석 소프트웨어의 일부 모듈에 ACIS 형식으로 저장 솔리드 형상을 가져 오기이다. </li><li> FEA 소프트웨어의 일부 모델러의 스텐트에 동축 2 분석 실린더 모델입니다. 외측 실린더는 크림 퍼 시뮬레이션 스텐트의 직경보다 큰 직경을 갖는 초기 및 내측 실린더는 인플레이션 풍선을 시뮬레이트하도록 1mm의 초기 직경을 갖는다. </li><li> 위를 조립하는 어셈블리 모델러의 &#39;인스턴스&#39;트리 항목을 더블 클릭 상대 위치에 부품을 말했다. </li><li> 감소 통합 20 노드 육면체 요소로서 요소 유형을 지정 FEA 소프트웨어 메쉬 모듈을 사용하여 소자의 크기를 지정하고, 상기 스텐트 메쉬. </li><li> 스텐트 및 모델 트리의 &#39;상호 작용의 특성&#39;에 각각 두 개의 실린더 사이의 마찰 강성 접촉 쌍을 지정합니다. </li><li> 스텐트 모델로 2205 스테인레스 스틸의 탄소 성 응력 - 변형 동작을 지정합니다. </li><li> 우선 C 시뮬레이션 1mm로 외통 압착하는 경계 조건을 정의스텐트의 rimping. 압착 스텐트의 휴식을 시뮬레이션하기 위해 외부 실린더를 제거합니다. 확장을 시뮬레이션 3mm로 내부 실린더를 확장하고 마지막으로, 스텐트의 반동을 시뮬레이션 할 수있는 내부 실린더를 제거합니다. </li><li> &#39;분석&#39;모델 트리 항목에 할당 된 프로세서와 RAM의 양의 수를 포함한 시뮬레이션 매개 변수를 정의하고 시뮬레이션을 실행합니다. </li><li> 시뮬레이션이 완료되면, 주 균주를 연구 결과 결과 파일 (filename.odb) 및 후 처리를 열고 반복적 재료의 파괴​​ 한도보다 작은 20 %의 주요 스트레인을 달성하기 위해 스텐트 디자인을 향상 . </li></ol></li></ol> 압착 및 확장 2. 스텐트 제조 및 테스트 <ol><li> 스텐트 제조 <ol><li> 이러한 개척자의 액션 정밀 제품으로 정밀 가공 회사에서 총 시추 및 정밀 연삭 바 원재료로 2205 스테인레스 스틸 튜브를 확보,OH. </li><li> 레이저 절단 및 전해에 대해 같은 워키 건, 일리노이 Laserage 기술 공사로 스텐트 절단 회사에 정밀 연마 튜브 및 플랫 패턴 스텐트 디자인을 전송합니다. </li><li> 또 다른 10 분 동안베이스 (10 %의 NaHCO3) 다음에 10 분 동안 강산 (50 % 염산)에 의해 그들을 담근다 전해 스텐트의 표면을 패시베이션. 주의 : 적절한 보호 장비와 흄 후드에서 화학 물질을 처리합니다. 마지막으로, 에틸 알코올 및 탈 이온수로 스텐트를 씻는다. 이 프로세스는 산세 불린다. </li></ol></li><li> 압착 및 확장을위한 제조 된 스텐트의 시험 <ol><li> 도구를 압착 개최 손을 사용하여 3 중 풍선에 스텐트를 압착. 스텐트와 압착 공구의 3 중 풍선을 잡으십시오. 방사상으로 풍선에 압착 할 수있는 스텐트를 변형 핸들을 누릅니다. </li><li> 균일 압착에 대한 현미경에 의한 구조의 실패의 흔적을 사용하여 압착 스텐트를 검사소성 변형. </li><li> 물 3 중 풍선을 가압하여 3mm의 설계 직경을 확장합니다. 미세 골절 균일 확장을위한 확장 된 스텐트를 검사합니다. </li></ol></li></ol> 잉여금 자기장에 대한 스텐트 3. 특성 주 : 2 인치 직경 1 인치의 높이의 원통 자석을이 연구에 사용 하였다. 자석의 극 축을 따라 정렬됩니다. 자석의 표면 자속 밀도는 약 1 T. <ol><li> 강한 네오디뮴 자석을 사용하여 직경 방향 또는 축 방향으로 자화 된 스텐트. 자화 약 1 분 동안 강한 자석에 가까운 스텐트를 잡습니다. </li><li> 직경 자기 또는 축 방향으로 자화 자기장 라인을 따라 축과 원통면 옆에 스텐트를 보유 할 자력선을 따라 직경이 평탄면 중 하나에 상기 스텐트를 잡아. 잉여금 자기 한 느낌스텐트의 D는 적어도 24 시간 동안 안정하지만, 자화 후 가능한 빨리 스텐트를 사용하는 것으로 확인되었다. </li><li> 유리 맨드릴 상에 개별적으로 스텐트를 장착 한 다음 자기 프로빙 조명기의 정밀 척에 유리 맨드릴 마운트. 자성 마이크로 센서 프로브 정확하게 XYZ가 자기 프로빙 어셈블리의 조명기를 사용하여 스테이지면 (도 4)를 만지지 않고 스텐트 부근에 위치 될 수있다. </li><li> 멀리 스텐트에서 자성 마이크로 센서의 기준선 판독을 측정하고 자기 프로빙 조명기의 XYZ 스테이지를 사용하여 프로브를 위치시킴으로써 상기 스텐트의 표면에 잔류 자기장을 측정한다. </li></ol> 4. 자기 세포 캡처 연구 <ol><li> 얻기 세포, 형광 염료와 SPION 및 염색 라벨 <ol><li> 5,7에 기재된 돼지의 말초 혈액으로부터 내피 세포 생장 (EOC)를 도출. unti했다 T-75 플라스크 문화L 약 80 %의 합류 (5 × 6 6 8X10에 세포). </li><li> 10 nm의 직경 마그네타이트 FE (3 O 4) 8,9에 기재된 바와 같이 50 nm 두께의 폴리 (락트산 - 코 - 글리콜 산) (PLGA) 쉘에 의해 둘러싸인 코어로서 SPIONs 합성. </li><li> O 37 ℃에서 16 시간 동안 세포 배양 배지의 200 μg / ml의 농도로 유도 SPION EOC 부화 </li><li> 부드럽게 세포 배양 배지를 흡인. 부드럽게 플라스크에 인산 완충 식염수 (PBS) 10 ㎖를 첨가 요동하고 PBS를 흡입하여 세포를 세척한다. </li><li> 실험 중 시각화 형광 염료 (CM-DII)와 세포를 얼룩. 이는 5 μL / ㎖의 농도로 세포 배양 배지 10 ㎖에 염료를 첨가하여 37 ℃에서 30 분 동안 세포와 함께 배양하여 제조사의 지침에 따라 수행된다. </li><li> 단계 4.1.4에서와 같이 PBS로 세포를 세척하고 37 ℃에서 5 분 동안 0.25 % 트립신 EDTA 용액 3 ㎖로 배양플라스크에서 세포를 올립니다. </li><li> 5 분 세포 펠렛을 형성하기 위해 500 XG에 PBS로, 15ml의 원뿔형 튜브에 가기를 세포 현탁액을 전송하고, 원심 분리기. </li><li> 1-2x10 106 세포 / ml의 농도로 PBS에 세포 펠렛을 다시 중지하고 수회와 원추형 튜브의 피펫 팅하여 잘 혼합한다. </li></ol></li><li> 체외 세포 연구 <ol><li> 설계 및 제작합니다 (예를 들어, 3D 인쇄) 단지 유리 커버 슬립의 표면 위의 스텐트를 유지하는 간단한기구. </li><li> 전자기 자기야을 이용한 스텐트 탈자 또는 강한 네오디뮴 자석을 사용하여 직경 방향 또는 축 방향으로 자화 스텐트. </li><li> 축 방향으로 자화 된 직경 자기 또는 비 착자 제어 스텐트를 포함하는 접시로 PBS에 현탁 SPION 라벨링 EOC 피펫. 이미지 반전 형광 현미경을 사용하여 즉시 형광을 위해 PBS에 현탁 EOC와 스텐트. </li></ol></li></ol><p클래스 = &quot;jove_title&quot;&gt; 5. 인 - 생체 내 동물 연구 <ol><li> 스텐트 시술 <ol><li> 4 건강한 요크셔 돼지에서 말초 혈액을 그립니다 - 5,7에 설명 된대로 삼주 전에 각각 주입 스텐트 문화 EOC하기 - 약 50 kg의 무게. </li><li> (매일 아스피린 325 밀리그램과 클로피도그렐 75 mg)을 수술 3 일전부터 항 혈소판 약물을 관리합니다. </li><li> 스텐트 시술 당일, 근육 Telazol, 크 실라와 아트로핀과 돼지를 마취 (5 / 2-3 / 0.05 밀리그램 / 각각 ㎏) 해당 기관의 동물 관리 및 사용 지침에 명시된대로. </li><li> 삽관 및 1-2.5 % 아이소 플루 란 마취의 흡입에 돼지를 놓습니다. </li><li> 돼지의 복부 목 영역을 면도하고 일반 멸균 조건의 절차를 실시하고 있습니다. </li><li> 임플란트 (1) 및 기준 자화 심장 도관 기술을 이용하여 우측 관상 동맥 (RCA)에 1 비자 성 스텐트. <ol><li> Cathete동물의 rization은 훈련 중재 심장 전문의에 의해 수행되어야한다. 9 프랑스어 칼집과 오른쪽 경동맥에 액세스 할 수 있습니다. </li><li> 목표 관상 동맥 Cannulate 및 투시 화상을 얻기 위해 요오드화 조영제를 주입. </li><li> 동맥에서 0.014 인치 표준 관상 동맥 가이드 와이어를 놓습니다. 풍선을 사전이 가이드 와이어를 이용하여 스텐트 3-3.5 mm 직경의 혈관에 스텐트를 배포합니다. </li></ol></li><li> 와이어 풍선 위에를 사용하여 이식 된 스텐트에 대한 RCA 근위 내의 혈류를 폐색하고 2 분 동안 중심 카테터를 통해 PBS 4 mL에 현탁 SPION 표지 약 2 × 6자가 EOC을 제공한다. </li><li> 추가 폐색의 2 분 후 RCA 혈액의 흐름을 복원합니다. </li><li> 회복실에 동물을 전송하고이 의식을 회복 할 때까지 밀접하게 동물을 모니터링 할 수 있습니다. </li><li> 항 혈소판 약물을 투여 계속 (아스피린 325 밀리그램과 클로피도그렐 75mg)을 희생 할 때까지 작동 가능 게시합니다. </li></ol></li><li> 스텐트 이식편 및 조직학 <ol><li> 이전에 설명한 바와 같이 첫 번째 동물을 마취하여 동물에게 수술 후 7 일 안락사 후 정맥 적용 기관 동물 관리 및 사용 지침에 따라 나트륨 펜 토바 비탈 (100 ㎎ / ㎏)의 치사량을 관리 할 수​​ 있습니다. </li><li> 수술 스텐트 동맥 세그먼트를 수확. 30 분 이상 동안 10 % 포르말린 버퍼 외식 동맥 수정. 또한 조직 학적 분석을 위해 포르말린 버퍼에 샘플을 남겨주세요. </li><li> 금속 스텐​​트 조직학을 수행 할 수있는 설비에 고정 된 샘플을 아웃소싱. 이 처리 중에, 샘플은, 메틸에 포함되는 횡단 및 철 입자 러시안 블루 염색으로 염색 된 Mallory의 기법을 사용하여 조직 학적 분석. </li></ol></li></ol>

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G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Locally+targeted+drug+delivery+to+magnetic+stents+for+therapeutic+applications.">Locally targeted drug delivery to magnetic stents for therapeutic applications.</a> Computer Architectures for Machine Perception, 2003 IEEE International Workshop on. , 1-6 (2003).</li><li>Rathel, T., 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=Magnetic+Stents+Retain+Nanoparticle-Bound+Antirestenotic+Drugs+Transported+by+Lipid+Microbubbles.">Magnetic Stents Retain Nanoparticle-Bound Antirestenotic Drugs Transported by Lipid Microbubbles.</a> Pharm Res-Dordr. 29 (5), 1295-1307 (2012).</li><li>Gunn, J., Cumberland, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stent+coatings+and+local+drug+delivery+-+state+of+the+art.">Stent coatings and local drug delivery - state of the art.</a> Eur Heart J. 20 (23), 1693-1700 (1999).</li><li>Lu, A., Jia, G., Gao, G., Wang, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+magnetic+stent+on+coronary+restenosis+after+percutaneous+transluminal+coronary+angioplasty+in+dogs.">The effect of magnetic stent on coronary restenosis after percutaneous transluminal coronary angioplasty in dogs.</a> Chin Med J (Engl. 114 (8), 821-823 (2001).</li><li>Kempe, H., Kempe, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+magnetite+nanoparticles+for+implant-assisted+magnetic+drug+targeting+in+thrombolytic+therapy.">The use of magnetite nanoparticles for implant-assisted magnetic drug targeting in thrombolytic therapy.</a> Biomaterials. 31 (36), 9499-9510 (2010).</li><li>Chorny, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Targeting+stents+with+local+delivery+of+paclitaxel-loaded+magnetic+nanoparticles+using+uniform+fields.">Targeting stents with local delivery of paclitaxel-loaded magnetic nanoparticles using uniform fields.</a> P Natl Acad Sci USA. 107 (18), 8346-8351 (2010).</li><li>Polyak, B., Friedman, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+targeting+for+site-specific+drug+delivery:+applications+and+clinical+potential.">Magnetic targeting for site-specific drug delivery: applications and clinical potential.</a> Expert Opin Drug Del. 6 (1), 53-70 (2009).</li><li>Liu, J. Y., 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=Magnetic+stent+hyperthermia+for+esophageal+cancer:+an+in+vitro+investigation+in+the+ECA-109+cell+line.">Magnetic stent hyperthermia for esophageal cancer: an in vitro investigation in the ECA-109 cell line.</a> Oncol Rep. 27 (3), 791-797 (2012).</li><li>Gunn, J., Cumberland, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Does+stent+design+influence+restenosis.">Does stent design influence restenosis.</a> Eur Heart J. 20 (14), 1009-1013 (1999).</li><li>Aviles, M. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+vitro+study+of+ferromagnetic+stents+for+implant+assisted-magnetic+drug+targeting.">In vitro study of ferromagnetic stents for implant assisted-magnetic drug targeting.</a> J Magn Magn Mater. 311 (1), 306-311 (2007).</li><li>Mardinoglu, 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=Theoretical+modelling+of+physiologically+stretched+vessel+in+magnetisable+stent+assisted+magnetic+drug+targeting+application.">Theoretical modelling of physiologically stretched vessel in magnetisable stent assisted magnetic drug targeting application.</a> J Magn Magn Mater. 323 (3-4), 324-329 (2011).</li><li>Liu, Z. Y., 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=Stress+corrosion+cracking+of+2205+duplex+stainless+steel+in+H2S-CO2+environment.">Stress corrosion cracking of 2205 duplex stainless steel in H2S-CO2 environment.</a> J Mater Sci. 44 (16), 4228-4234 (2009).</li><li>Alverez-Armas, I., Degallaix-Moreuill, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Duplex stainless steels. , (2009).</li><li>Tefft, B. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetizable+Duplex+Steel+Stents+Enable+Endothelial+Cell+Capture.">Magnetizable Duplex Steel Stents Enable Endothelial Cell Capture.</a> Ieee T Magn. 49 (1), 463-466 (2013).</li><li>Pelton, A. R., 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=Fatigue+and+durability+of+Nitinol+stents.">Fatigue and durability of Nitinol stents.</a> J Mech Behav Biomed Mater. 1 (2), 153-164 (2008).</li><li>Knowles, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Finite+element+analysis+of+a+balloon-expandable+stent+and+superior+mesenteric+arterial+wall+interaction.">Finite element analysis of a balloon-expandable stent and superior mesenteric arterial wall interaction.</a> J Vasc Surg. 60 (6), 1722-1723 (2014).</li><li>Veeram Reddy, S. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+biodegradable+stent+applicable+for+use+in+congenital+heart+disease:+bench+testing+and+feasibility+results+in+a+rabbit+model.">A novel biodegradable stent applicable for use in congenital heart disease: bench testing and feasibility results in a rabbit model.</a> Catheter Cardiovasc Interv. 83 (3), 448-456 (2014).</li><li>Shellock, F. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MR+imaging+of+metallic+implants+and+materials:+a+compilation+of+the+literature.">MR imaging of metallic implants and materials: a compilation of the literature.</a> AJR Am J Roentgenol. 151 (4), 811-814 (1988).</li><li>Lopic, N., 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=Quantitative+determination+of+magnetic+force+on+a+coronary+stent+in+MRI.">Quantitative determination of magnetic force on a coronary stent in MRI.</a> J Magn Reson Imaging. 37 (2), 391-397 (2013).</li></ol>

The authors declare that they have no competing financial interests.

우리는 베어 메탈 스텐트의 기능을 할 수 있으며 SPION 표지 내피 세포를 유치 할 수있는 자기 스텐트를 개발했다. 자기 스텐트와 관련된 이전 연구에서 연구팀은 (는) 강자성 스텐트 5,10-14의 불가능에 자성 재료로 만든 니켈 코팅 된 상업 스텐트 및 코일 또는 메쉬를 사용했습니다. 다른 그룹은 나노 입자로드 내피 세포 3을 대상으로 시판 304 등급의 스테인레스 스틸 스텐트의 상자?...

Patients implanted with vascular stents manufactured from thrombogenic materials like stainless steel, cobalt chromium, and platinum chromium &#8211; both bare metal stents (BMS) and drug eluting stents (DES) &#8211; need anti-platelet therapy to prevent thrombus formation. BMS heal rapidly, but are subject to late stage restenosis due to incomplete healing. DES require long term anti-platelet therapy due to delayed healing. Anti-platelet therapy administered to avoid thrombosis as a result of incomplete or delayed healing leads to increased bleeding risk and may not be suitable for certain patients1,2. An ideal stent will heal completely and quickly thus avoiding long-term anti-platelet therapy and late stage restenosis. This complete healing can only be achieved if the stent is rapidly coated with a monolayer of endothelial cells after implantation. Coating the stents with biocompatible materials such as gold or other biopolymers has been shown to improve thrombo-resistance, but none of these techniques achieved ideal blood compatibility as may be possible by coating with endothelial cells3,4.
A stent can be coated with endothelial cells post implantation by attracting circulating progenitor cells. This self-seeding technique can be achieved by utilizing ligands and antibodies. But this technique is limited by the low number of circulating endothelial progenitor cells. A promising strategy is to deliver cells directly to the stent immediately following implantation during a short period of blood flow occlusion3,5. This strategy requires a technique for rapidly capturing cells and retaining them on the stent even after restoring blood flow. We have developed a technique in which a magnetic stent is used to attract and retain magnetically-labeled endothelial cells delivered post implantation. To achieve this, a functional BMS with sufficient magnetic properties to capture and retain magnetically-labeled endothelial cells is required6.
In this paper, we discuss the methods for designing, manufacturing, and testing a 2205 stainless steel stent. The stents were designed using CAD and FEA. The manufactured stents were magnetized using a neodymium magnet and the retained magnetic field was measured using a magneto-resistance microsensor probe. We then tested the stents for magnetically-labeled cell capture in a culture dish during our in-vitro experiments. Finally, the stents were tested in-vivo by implanting magnetic and non-magnetic stents in 4 pigs and histologically analyzing the stented arteries.

<table><tbody><tr><td>2205 Stainless steel</td><td>Carpenter Technology Corporation</td><td></td><td>Round bar stock material</td></tr><tr><td>Abaqus</td><td>Dassault systems</td><td></td><td>Software</td></tr><tr><td>Atropine</td><td></td><td></td><td>Prescription drug.</td></tr><tr><td>Clopidogrel</td><td></td><td></td><td>Commercial name: Plavix. Prescription drug.</td></tr><tr><td>CM-DiI</td><td>Life Technologies</td><td>V-22888</td><td>Molecular Probes, Eugene, OR</td></tr><tr><td>Endothelial growth medium-2</td><td>Lonza</td><td>CC-3162</td><td></td></tr><tr><td>Hand Held Crimping tool</td><td>Blockwise engineering</td><td>M1-RMC</td><td></td></tr><tr><td>Hydrochloric acid (HCl)</td><td>Sigma Aldrich</td><td>MFCD00011324</td><td>CAUTION: wear proptective equipment and handle under fume hood</td></tr><tr><td>Isoflurane anesthesia</td><td>Piramal Critical Care, Inc.&amp;nbsp;</td><td></td><td></td></tr><tr><td>Ethyl alcohol</td><td>Sigma Aldrich</td><td>MFCD00003568</td><td></td></tr><tr><td>NdFeB magnet 2&quot; Dia x 1&quot; thick</td><td>Amazing magnets</td><td>D1000P</td><td>Axially magnetized disc magnet with poles on flat faces</td></tr><tr><td>Over-The-Wire trifold balloon</td><td></td><td></td><td>Any commercially available OTW trifold balloon can be used</td></tr><tr><td>Phosphate buffered saline</td><td>Life Technologies</td><td>10010-023</td><td>Commonly known as PBS</td></tr><tr><td>Sodium Bicarbonate (NaHCO3)</td><td>Sigma Aldrich</td><td>MFCD00003528</td><td></td></tr><tr><td>Sodium pentobarbital</td><td>Zoetis</td><td></td><td>Commercial Name: Sleepaway (26%), FatalPlus, Beuthanasi.&amp;nbsp; Controlled substance to be ordered only by licensed veternarian</td></tr><tr><td>SolidWorks</td><td>Dassault systems</td><td></td><td>Software</td></tr><tr><td>SpinTJ-020 micro sensor</td><td>MicroMagneitcs Sensible Solutions</td><td></td><td>Long probe STJ-020 microsensor</td></tr><tr><td>SPION</td><td>Mayo Clinic</td><td></td><td>Nanoparticles synthesized internally (Ref: Lee, S. J. et al. Nanoparticles of magnetic ferric oxides encapsulated with poly(D,L latide-co-glycolide) and their applications to magnetic resonance imaging contrast agent. J Magn Magn Mater 272, 2432-2433, doi:DOI 10.1016/j.jmmm.2003.12.416 (2004))</td></tr><tr><td>Telazol</td><td>Zoetis</td><td></td><td>Controlled substance to be ordered only by licensed veternarian</td></tr><tr><td>Trypsin EDTA</td><td>Life Technologies</td><td>25200-056</td><td>Gibco, Grand Island, NY</td></tr><tr><td>Xylazine</td><td>Bayer Animal Health</td><td></td><td>Commercial name: Rompun. Controlled sunstance to be ordered only by a licensed veternarian</td></tr></tbody></table>

ferromagnetic bare metal stent for endothelial cell capture and retention

심혈관 스텐트에 내피 세포가 급속 스텐트 혈전증을 감소시키고 출혈 위험을 줄일 수있는 항 혈소판 요법을 피하기 위해 필요하다. 초 상자성 산화철 나노 입자 (SPION)로 표지 내피 세포 생장 (EOC)를 캡쳐하고 유지하기 위해 자력을 이용의 가능성은 이미 밝혀졌다. 그러나이 기술은 빠른에 내피 증명 시험관 내 및 생체 내 시험 하였다 자기 및 생체 물질로부터 기계적 작용 성 스텐트의 개발이 필요하다. 우리는 컴퓨터 이용 설계 (CAD)를 이용하여 2,205 듀플렉스 스테인레스 약하게 강자성 스텐트를 개발하고 설계는 또한 유한 요소 해석 (FEA)을 사용하여 정제 하였다. 스텐트의 최종 설계는 기계적 권축과 팽창시에 재료의 파단 한계 이하 주 변형률을 나타냈다. 백 스텐트를 제작하고, 그 중 일부는 기계적 시험, RET에 사용 된ained 자기장 측정 시험관 세포 캡처 연구 및 생체 내 주입 연구. 텐 스텐트은 실패없이 사이클을 압착 및 확장 입었 있는지 확인하기 위해 배포를 테스트 하였다. 다른 스텐트 (10)는 강한 네오디뮴 자석을 이용하고, 그들의 자화 유지 자기장을 측정 하였다. 스텐트는 유지 자기가 우리의 시험관 연구에서 SPION 표지 EOC를 캡처하기에 충분한 것으로 나타났다. SPION 표지 EOC 캡처 및 보유 1 자화 스텐트 4 돼지의 각 1 비 자화 제어 스텐트를 주입하여 큰 동물 모델에서 확인되었다. 스텐트 동맥 7 일 이후 외식 및 조직 학적으로 분석 하였다. 본 연구에서 개발 된 약하게 자기 스텐트 유치와 빠른 치유를 촉진 할 수 SPION 표지 내피 세포를 보유 할 수 있었다.

<html> FEA (도 1)에 기초하여 반복적 스텐트 디자인은 압착 및 30 %의 궁극적 인 스트레인 미만 20 %의 주요 균주 스텐트 확장 할 수 있었다. 압착 및 확장 테스트 (그림 2) 골절의 징후를 보이지 않았다. 변형 된 스텐트의 사진은 FEA 계산 변형와 잘 일치를 보였다 또한 현미경 사진은 골절을 (그림 3)가 없었다. 유지 자기장 측정 (그림 4 및 5)에서 예상대?...

Watch this Scientific Journal Video about Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention at JoVE.com

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention

우리의 목표는 설계, 제조 및 내피 세포 캡처를위한 강자성 스텐트를 테스트했다. 열 스텐트 파괴에 대해 시험하고, 10 이상이 유지 자성 스텐트에 대해 시험 하였다. 마지막으로, 10 스텐트는 시험관 시험하고 8 개의 스텐트는 세포 캡처 및 보존을 보여 4 돼지에 이식했다.

내피 세포 캡처 및 유지에 대한 강자성 베어 메탈 스텐트

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. ...

ferromagnetic-bare-metal-stent-for-endothelial-cell-capture

Universidad de Cartagena UDEC

Research

JoVE Journal

Bioengineering

11.5K 조회수.  Mayo Clinic.  우리의 목표는 설계, 제조 및 내피 세포 캡처를위한 강자성 스텐트를 테스트했다. 열 스텐트 파괴에 대해 시험하고, 10 이상이 유지 자성 스텐트에 대해 시험 하였다. 마지막으로, 10 스텐트는 시험관 시험하고 8 개의 스텐트는 세포 캡처 및 보존을 보여 4 돼지에 이식했다. 

비디오: Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention

Labeling Stem Cells with Ferumoxytol, an FDA-Approved Iron Oxide Nanoparticle

Stem cell based therapies offer significant potential for the field of regenerative medicine. However, much remains to be understood regarding the in vivo kinetics of transplanted cells. A non-invasive method to repetitively monitor transplanted stem cells in vivo would allow investigators to directly monitor stem cell transplants and identify successful or unsuccessful engraftment outcomes.
A wide range of stem cells continues to be investigated for countless applications. This protocol focuses on 3 different stem cell populations: human embryonic kidney 293 (HEK293) cells, human mesenchymal stem cells (hMSC) and induced pluripotent stem (iPS) cells. HEK 293 cells are derived from human embryonic kidney cells grown in culture with sheared adenovirus 5 DNA. These cells are widely used in research because they are easily cultured, grow quickly and are easily transfected. hMSCs are found in adult marrow. These cells can be replicated as undifferentiated cells while maintaining multipotency or the potential to differentiate into a limited number of cell fates. hMSCs can differentiate to lineages of mesenchymal tissues, including osteoblasts, adipocytes, chondrocytes, tendon, muscle, and marrow stroma. iPS cells are genetically reprogrammed adult cells that have been modified to express genes and factors similar to defining properties of embryonic stem cells. These cells are pluripotent meaning they have the capacity to differentiate into all cell lineages 1. Both hMSCs and iPS cells have demonstrated tissue regenerative capacity in-vivo.
Magnetic resonance (MR) imaging together with the use of superparamagnetic iron oxide (SPIO) nanoparticle cell labels have proven effective for in vivo tracking of stem cells due to the near microscopic anatomical resolution, a longer blood half-life that permits longitudinal imaging and the high sensitivity for cell detection provided by MR imaging of SPIO nanoparticles 2-4. In addition, MR imaging with the use of SPIOs is clinically translatable. SPIOs are composed of an iron oxide core with a dextran, carboxydextran or starch surface coat that serves to contain the bioreactive iron core from plasma components. These agents create local magnetic field inhomogeneities that lead to a decreased signal on T2-weighted MR images 5. Unfortunately, SPIOs are no longer being manufactured. Second generation, ultrasmall SPIOs (USPIO), however, offer a viable alternative. Ferumoxytol (FerahemeTM) is one USPIO composed of a non-stoichiometric magnetite core surrounded by a polyglucose sorbitol carboxymethylether coat. The colloidal, particle size of ferumoxytol is 17-30 nm as determined by light scattering. The molecular weight is 750 kDa, and the relaxivity constant at 2T MRI field is 58.609 mM-1 sec-1 strength4. Ferumoxytol was recently FDA-approved as an iron supplement for treatment of iron deficiency in patients with renal failure 6. Our group has applied this agent in an &ldquo;off label&rdquo; use for cell labeling applications. Our technique demonstrates efficient labeling of stem cells with ferumoxytol that leads to significant MR signal effects of labeled cells on MR images. This technique may be applied for non-invasive monitoring of stem cell therapies in pre-clinical and clinical settings.

We describe a technique for labeling and tracking stem cells with FDA-approved, superparamagnetic iron oxide (SPIO), ferumoxytol (Feraheme). This cellular imaging technique that utilizes magnetic resonance (MR) imaging for visualization, is readily accessible for long-term monitoring and diagnosis of successful or unsuccessful stem cell engraftments in patients.

Ferumoxytol, FDA 승인 철 산화물 Nanoparticle과 함께 줄기 세포를 라벨링

Stem cell based therapies offer significant potential for the field of regenerative medicine. However, much remains to be understood regarding the in vivo ...

연구

의학

A Murine Model of Stent Implantation in the Carotid Artery for the Study of Restenosis

Despite the considerable progress made in the stent development in the last decades, cardiovascular diseases remain the main cause of death in western countries. Beside the benefits offered by the development of different drug-eluting stents, the coronary revascularization bears also the life-threatening risks of in-stent thrombosis and restenosis. Research on new therapeutic strategies is impaired by the lack of appropriate methods to study stent implantation and restenosis processes. Here, we describe a rapid and accessible procedure of stent implantation in mouse carotid artery, which offers the possibility to study in a convenient way the molecular mechanisms of vessel remodeling and the effects of different drug coatings.

A model of stent implantation in mouse carotid artery is described. Compared to other similar methods, this procedure is very rapid, simple and accessible, offering the possibility to study in a convenient way the vascular wall reaction to different drug-eluting stents and the molecular mechanisms of restenosis.

재 협착의 연구에 대한 경동맥 스텐트 시술의 쥐과 모형

Despite  the considerable progress made in the stent development in the last decades,  cardiovascular diseases remain the main cause of death in western ...

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Targeted delivery of cells and therapeutic agents would benefit a wide range of biomedical applications by concentrating the therapeutic effect at the target site while minimizing deleterious effects to off-target sites. Magnetic cell targeting is an efficient, safe, and straightforward delivery technique. Superparamagnetic iron oxide nanoparticles (SPION) are biodegradable, biocompatible, and can be endocytosed into cells to render them responsive to magnetic fields. The synthesis process involves creating magnetite (Fe3O4) nanoparticles followed by high-speed emulsification to form a poly(lactic-co-glycolic acid) (PLGA) coating. The PLGA-magnetite SPIONs are approximately 120 nm in diameter including the approximately 10 nm diameter magnetite core. When placed in culture medium, SPIONs are naturally endocytosed by cells and stored as small clusters within cytoplasmic endosomes. These particles impart sufficient magnetic mass to the cells to allow for targeting within magnetic fields. Numerous cell sorting and targeting applications are enabled by rendering various cell types responsive to magnetic fields. SPIONs have a variety of other biomedical applications as well including use as a medical imaging contrast agent, targeted drug or gene delivery, diagnostic assays, and generation of local hyperthermia for tumor therapy or tissue soldering.

Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.

셀 라벨 및 초상 자성 산화철 나노 입자로 타겟팅

Targeted delivery of cells and therapeutic agents would benefit a wide range of biomedical applications by concentrating the therapeutic effect at the ...

생체공학

Vascular Gene Transfer from Metallic Stent Surfaces Using Adenoviral Vectors Tethered through Hydrolysable Cross-linkers

In-stent restenosis presents a major complication of stent-based revascularization procedures widely used to re-establish blood flow through critically narrowed segments of coronary and peripheral arteries. Endovascular stents capable of tunable release of genes with anti-restenotic activity may present an alternative strategy to presently used drug-eluting stents. In order to attain clinical translation, gene-eluting stents must exhibit predictable kinetics of stent-immobilized gene vector release and site-specific transduction of vasculature, while avoiding an excessive inflammatory response typically associated with the polymer coatings used for physical entrapment of the vector. This paper describes a detailed methodology for coatless tethering of adenoviral gene vectors to stents based on a reversible binding of the adenoviral particles to polyallylamine bisphosphonate (PABT)-modified stainless steel surface via hydrolysable cross-linkers (HC). A family of bifunctional (amine- and thiol-reactive) HC with an average t1/2 of the in-chain ester hydrolysis ranging between 5 and 50 days were used to link the vector with the stent. The vector immobilization procedure is typically carried out within 9 hr&#160;and consists of several steps: 1) incubation of the metal samples in an aqueous solution of PABT (4 hr); 2) deprotection of thiol groups installed in PABT with tris(2-carboxyethyl) phosphine (20 min); 3) expansion of thiol reactive capacity of the metal surface by reacting the samples with polyethyleneimine derivatized with pyridyldithio (PDT) groups (2 hr); 4) conversion of PDT groups to thiols with dithiothreitol (10 min); 5) modification of adenoviruses with HC (1 hr); 6) purification of modified adenoviral particles by size-exclusion column chromatography (15 min) and 7) immobilization of thiol-reactive adenoviral particles on the thiolated steel surface (1 hr). This technique has wide potential applicability beyond stents, by facilitating surface engineering of bioprosthetic devices to enhance their biocompatibility through the substrate-mediated gene delivery to the cells interfacing the implanted foreign material.

These studies report on reversible attachment of adenoviral gene vectors to coatless metal surfaces of stents and model mesh disks. Sustained release of transduction-competent viral particles contingent upon hydrolysis of cross-linkers used for vector immobilization results in a durable site-specific transgene expression in vascular cells and in stented arteries.

가수 분해 크로스 링커를 통해 아데노 바이러스 벡터 닿는를 사용하여 금속 스텐​​트 표면에서 혈관 유전자 전송

In-stent restenosis presents a major complication of stent-based revascularization procedures widely used to re-establish blood flow through critically ...

Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide nanoparticles (SPIONs). Achieving sufficient cellular uptake of SPIONs is a challenge that has traditionally been met by exposing cells to elevated concentrations of SPIONs or by prolonging exposure times (up to 72 hr). However, these strategies are likely to mediate toxicity. Here, we present the synthesis of the protein-based SPION magnetoferritin as well as a facile surface functionalization protocol that enables rapid cell magnetization using low exposure concentrations. The SPION core of magnetoferritin consists of cobalt-doped iron oxide with an average particle diameter of 8.2 nm mineralized inside the cavity of horse spleen apo-ferritin. Chemical cationization of magnetoferritin produced a novel, highly membrane-active SPION that magnetized human mesenchymal stem cells (hMSCs) using incubation times as short as one minute and iron concentrations as lows as 0.2 mM.

A protocol for the synthesis and cationization of cobalt-doped magnetoferritin is presented, as well as a method to rapidly magnetize stem cells with cationized magnetoferritin.

세포의 초고속 자화에 대한 양이온 Magnetoferritin의 합성

Many important biomedical applications, such as cell imaging and remote manipulation, can be achieved by labeling cells with superparamagnetic iron oxide ...

3D Magnetic Stem Cell Aggregation and Bioreactor Maturation for Cartilage Regeneration

Cartilage engineering remains a challenge due to the difficulties in creating an in vitro functional implant similar to the native tissue. An approach recently explored for the development of autologous replacements involves the differentiation of stem cells into chondrocytes. To initiate this chondrogenesis, a degree of compaction of the stem cells is required; hence, we demonstrated the feasibility of magnetically condensing cells, both within thick scaffolds and scaffold-free, using miniaturized magnetic field sources as cell attractors. This magnetic approach was also used to guide aggregate fusion and to build scaffold-free, organized, three-dimensional (3D) tissues several millimeters in size. In addition to having an enhanced size, the tissue formed by magnetic-driven fusion presented a significant increase in the expression of collagen II, and a similar trend was observed for aggrecan expression. As the native cartilage was subjected to forces that influenced its 3D structure, dynamic maturation was also performed. A bioreactor that provides mechanical stimuli was used to culture the magnetically seeded scaffolds over a 21-day period. Bioreactor maturation largely improved chondrogenesis into the cellularized scaffolds; the extracellular matrix obtained under these conditions was rich in collagen II and aggrecan. This work outlines the innovative potential of magnetic condensation of labeled stem cells and dynamic maturation in a bioreactor for improved chondrogenic differentiation, both scaffold-free and within polysaccharide scaffolds.

Chondrogenesis from stem cells requires fine tuning the culture conditions. Here, we present a magnetic approach for condensing cells, an essential step to initiate chondrogenesis. In addition, we show that dynamic maturation in a bioreactor applies mechanical stimulation to the cellular constructs and enhances cartilaginous extracellular matrix production.

연골 재생을위한 3D 자기 줄기 세포 집계 및 생물 반응기 성숙

Cartilage engineering remains a challenge due to the difficulties in creating an in vitro functional implant similar to the native tissue. An approach ...

Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents

Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and perforations in vasculature. Such stent-grafts are manufactured by covering a stent with a polymer membrane. An ideal stent-graft should have a biocompatible stent covered by a porous, thromboresistant, and biocompatible polymer membrane which mimics the extracellular matrix thereby promoting injury site healing. The goal of this protocol is to manufacture a small caliber stent-graft by encapsulating a balloon expandable stent within two layers of electrospun polyurethane nanofibers. Electrospinning of polyurethane has been shown to assist in healing by mimicking native extracellular matrix, thereby promoting endothelialization. Electrospinning polyurethane nanofibers on a slowly rotating mandrel enabled us to precisely control the thickness of the nanofibrous membrane, which is essential to achieve a small caliber balloon expandable stent-graft. Mechanical validation by crimping and expansion of the stent-graft has shown that the nanofibrous polyurethane membrane is sufficiently flexible to crimp and expand while staying patent without showing any signs of tearing or delamination. Furthermore, stent-grafts fabricated using the methods described here are capable of being implanted using a coronary intervention procedure using standard size guide catheters.

In the protocol, we present a method to manufacture a small caliber stent-graft by sandwiching a balloon expandable stent between two electrospun nanofibrous polyurethane layers.

전기 방사 및 풍선 확장 베어 메탈 스텐트를 사용하여 작은 구경 스텐트 - 이식의 제작

Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and ...

Biodegradable Magnesium Stent Treatment of Saccular Aneurysms in a Rat Model - Introduction of the Surgical Technique

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable experimental animal models to test novel embolization materials such as stents and flow diverters. The aim of the present project was to design a safe, fast, and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model.
Saccular aneurysms were created from an arterial graft from the descending aorta.The aneurysms were microsurgically transplanted through end-to-side anastomosis to the infrarenal abdominal aorta of a syngenic male Wistar rat weighing &#62;500 g. Following aneurysm anastomosis, aneurysm embolization was performed using balloon expandable magnesium stents (2.5 mm x 6 mm). The stent system was retrograde introduced from the lower abdominal aorta using a modified Seldinger technique.
Following a pilot series of 6 animals, a total of 67 rats were operated according to established standard operating procedures. Mean surgery time, mean anastomosis time, and mean suturing time of the artery puncture site were 167 &#177; 22 min, 26 &#177; 6 min and 11 &#177; 5 min, respectively. The mortality rate was 6% (n=4). The morbidity rate was 7.5% (n=5), and in-stent thrombosis was found in 4 cases (n=2 early, n=2 late in stent thrombosis).
The results demonstrate the feasibility of standardized stent occlusion of saccular sidewall aneurysms in rats - with low rates of morbidity and mortality. This stent embolization procedure combines the opportunity to study novel concepts of stent or flow diverter based devices as well as the molecular aspects of healing.

Reproducable experimental animal models are needed for the testing of novel embolization materials, which have been designed to treat endovascular occlusion of intracranial aneurysms (IA). The present study aims to develop a safe and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model.

쥐 모델-수술 방법의 소개에에서 Saccular 동맥 류의 생 분해성 마그네슘 스 텐트 치료

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable ...

신경과학

Mitigation of Blood Borne Cell Attachment to Metal Implants through CD47-Derived Peptide Immobilization

The key complications associated with bare metal stents and drug eluting stents are in-stent restenosis and late stent thrombosis, respectively. Thus, improving the biocompatibility of metal stents remains a significant challenge. The goal of this protocol is to describe a robust technique of metal surface modification by biologically active peptides to increase biocompatibility of blood contacting medical implants, including endovascular stents. CD47 is an immunological species-specific marker of self and has anti-inflammatory properties. Studies have shown that a 22 amino acid peptide corresponding to the Ig domain of CD47 in the extracellular region (pepCD47), has anti-inflammatory properties like the full-length protein. In vivo studies in rats, and ex vivo studies in rabbit and human blood experimental systems from our lab have demonstrated that pepCD47 immobilization on metals improves their biocompatibility by preventing inflammatory cell attachment and activation. This paper describes the step-by step protocol for the functionalization of metal surfaces and peptide attachment. The metal surfaces are modified using polyallylamine bisphosphate with latent thiol groups (PABT) followed by deprotection of thiols and amplification of thiol-reactive sites via reaction with polyethyleneimine installed with pyridyldithio groups (PEI-PDT). Finally, pepCD47, incorporating terminal cysteine residues connected to the core peptide sequence through a dual 8-amino-3,6-dioxa-octanoyl spacer, are attached to the metal surface via disulfide bonds. This methodology of peptide attachment to metal surface is efficient and relatively inexpensive and thus can be applied to improve biocompatibility of several metallic biomaterials.

Presented here is a protocol for appending peptide CD47 (pepCD47) to metal stents using polybisphosphonate chemistry. Functionalization of metal stents using pepCD47 prevents the attachment and activation of inflammatory cells thus improving their biocompatibility.

CD47 유래 펩타이드 고정화를 통해 금속 임플란트에 대한 혈액 매개 세포 부착 완화

The key complications associated with bare metal stents and drug eluting stents are in-stent restenosis and late stent thrombosis, respectively. Thus, ...

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene and cell therapies are highly promising alternative approaches for CVD treatment. However, the broad clinical application of gene therapy is greatly limited by the lack of suitable gene delivery systems. The development of appropriate gene delivery vectors can provide a solution to current challenges in cell therapy. In particular, existing drawbacks, such as limited efficiency and low cell retention in the injured organ, could be overcome by appropriate cell engineering (i.e., genetic) prior to transplantation. The presented protocol describes the efficient and safe transient modification of endothelial cells using a polyethyleneimine superparamagnetic magnetic nanoparticle (PEI/MNP)-based delivery vector. Also, the algorithm and methods for cell characterization are defined. The successful intracellular delivery of microRNA (miR) into human umbilical vein endothelial cells (HUVECs) has been achieved without affecting cell viability, functionality, or intercellular communication. Moreover, this approach was proven to cause a strong functional effect in introduced exogenous miR. Importantly, the application of this MNP-based vector ensures cell magnetization, with accompanying possibilities of magnetic targeting and non-invasive MRI tracing. This may provide a basis for magnetically guided, genetically engineered cell therapeutics that can be monitored non-invasively with MRI.

Preparation and In Vitro Characterization of Magnetized miR-modified Endothelial Cells

This manuscript describes the efficient, non-viral delivery of miR to endothelial cells by a PEI/MNP vector and their magnetization. Thus, in addition to genetic modification, this approach allows for magnetic cell guidance and MRI detectability. The technique can be used to improve the characteristics of therapeutic cell products.

준비 및<em&gt; 체외</em&gt; 자화 특성의 내피 세포를 미르 변성

To date, the available surgical and pharmacological treatments for cardiovascular diseases (CVD) are limited and often palliative. At the same time, gene ...

내피 세포 캡처 및 유지에 대한 강자성 베어 메탈 스텐트

요약

더 많은 비디오 탐색

이 비디오의 챕터

Ferumoxytol, FDA 승인 철 산화물 Nanoparticle과 함께 줄기 세포를 라벨링

재 협착의 연구에 대한 경동맥 스텐트 시술의 쥐과 모형

셀 라벨 및 초상 자성 산화철 나노 입자로 타겟팅

가수 분해 크로스 링커를 통해 아데노 바이러스 벡터 닿는를 사용하여 금속 스텐트 표면에서 혈관 유전자 전송

세포의 초고속 자화에 대한 양이온 Magnetoferritin의 합성

연골 재생을위한 3D 자기 줄기 세포 집계 및 생물 반응기 성숙

전기 방사 및 풍선 확장 베어 메탈 스텐트를 사용하여 작은 구경 스텐트 - 이식의 제작

쥐 모델-수술 방법의 소개에에서 Saccular 동맥 류의 생 분해성 마그네슘 스 텐트 치료

CD47 유래 펩타이드 고정화를 통해 금속 임플란트에 대한 혈액 매개 세포 부착 완화

준비 및

내피 세포 캡처 및 유지에 대한 강자성 베어 메탈 스텐트

요약

더 많은 비디오 탐색

이 비디오의 챕터

Ferumoxytol, FDA 승인 철 산화물 Nanoparticle과 함께 줄기 세포를 라벨링

재 협착의 연구에 대한 경동맥 스텐트 시술의 쥐과 모형

셀 라벨 및 초상 자성 산화철 나노 입자로 타겟팅

가수 분해 크로스 링커를 통해 아데노 바이러스 벡터 닿는를 사용하여 금속 스텐​​트 표면에서 혈관 유전자 전송

세포의 초고속 자화에 대한 양이온 Magnetoferritin의 합성

연골 재생을위한 3D 자기 줄기 세포 집계 및 생물 반응기 성숙

전기 방사 및 풍선 확장 베어 메탈 스텐트를 사용하여 작은 구경 스텐트 - 이식의 제작

쥐 모델-수술 방법의 소개에에서 Saccular 동맥 류의 생 분해성 마그네슘 스 텐트 치료

CD47 유래 펩타이드 고정화를 통해 금속 임플란트에 대한 혈액 매개 세포 부착 완화

준비 및

가수 분해 크로스 링커를 통해 아데노 바이러스 벡터 닿는를 사용하여 금속 스텐트 표면에서 혈관 유전자 전송