The authors wish to acknowledge funding from the European Regional Development Fund &#8211; FNUSA-ICRC (no. CZ.1.05/ 1.1.00/ 02.0123), the American Heart Association Scientist Development Grant (AHA #06-35185N), and the National Institutes of Health (NIH #T32HL007111).

자철광 젤 1. 합성 <ol><li> 에틸 알코올 다음에 탈 이온수 다음에 진한 염산을 사용하여 모든 유리 제품을 씻으십시오. 바람직하게는 건조 오븐에서, O / N을 건조하도록 허용합니다. 주의! 염산 유해 - 흄 후드에서 개인용 보호 장비는 작업을 착용; 에틸 알코올은 유해한 - 개인 보호 장비를 착용하십시오. </li><li> 탈 가스 탈 H 2 O의 500 mL로 부드럽게 30 분 동안 N 2 가스 버블 링에 의해 Dreschel 병을 사용합니다. </li><li> 셋업 화학 물질 흄 후드 내에서 자철광 합성 장치. <ol><li> isomantle 히터 내에 500㎖의 3 구 둥근 바닥 플라스크를 놓고 클램프를 사용하여 중심 목을 고정 및 스탠드. </li><li> 환저 플라스크의 목의 측면에 하나의 고무 격막 나머지 측 경부에 고무 격막과 환류 냉각기를 설치한다. 지속적으로 환류 냉각기를 통해 차가운​​ 물을 실행합니다. </li><li> 펑크 일E 환저 플라스크의 고무 N 2 가스 라인에 연결된 바늘을 격막과 기포에 실행 가스 라인에 연결된 바늘을 환류 응축기의 고무 격막을 천공 (즉, 물을 플라스크) 가스 유출을 시각화. </li><li> 패들 어댑터를 통해 둥근 바닥 플라스크의 중심 목에 블레이드 패를 설치합니다. 스탠드에 장착 된 오버 헤드 교반기에 블레이드 패의 샤프트를 연결합니다. </li></ol></li><li> N 2 가스로 둥근 바닥 플라스크를 제거하고 낮은하지만 검출 속도로 흐르는 N 2 가스를 둡니다. </li><li> 둥근 바닥 플라스크에서 환류 응축기를 제거하고, 철 (III) 클로라이드, 철 0.6125 g (II) 클로라이드 수화물 1.000 g을 추가하고, 탈기 H 2 O 50 ㎖ 주의! 철 (III) 클로라이드 및 철 (II) 클로라이드 테트라는 유해한 - 개인 보호 장비를 착용하십시오. </li><li> 50 가열하면서 환류 냉각기를 교체하고 1,000 rpm에서 교반° C. 이러한 조건에서 교반은 10 나노 미터 직경의 마그네타이트 나노 입자를 생성합니다. </li><li> 일단 50 ℃에서 계속 교반 둥근 바닥 플라스크에 고무 격막을 통해 주입하여, 28 % 수산화 암모늄 용액 10 ㎖를 추가한다. 주의! 수산화 암모늄은 유해한 - 개인 보호 장비를 착용하십시오. 주 : 수산화 암모늄 용액 마그네타이트를 침전 사용되고 용액 검게한다. </li><li> 계속 교반하면서 암모니아 가스를 끓여 90 ℃로 둥근 바닥 플라스크 및 열에서 고무 격막 및 N 2 가스 라인을 제거합니다. 주 : 환류 응축기의 고무 격막을 천공하여 둥근 바닥 플라스크에 N (2)의 흐름을 유지하는 것이 선택적이다, 그러나, 마그 헤 마이트에 마그네타이트의 산화가이 단계에서 무시할 수있다. </li><li> 계속 교반하면서 한 번에 90 ℃에서, 둥근 바닥 플라스크에 올레산 1 ㎖를 추가한다. 올레산 노나 코팅 마그네타이트를 사용noparticles는 마그네타이트 겔을 형성한다. 주의! 올레산은 유해 - 개인 보호 장비를 착용하십시오. </li><li> 둥근 바닥 플라스크에 고무 격막 및 N 2 가스 라인을 교체하고 환류 냉각기를 제거합니다. </li><li> 2 시간 동안 500 rpm에서 열 및 교반을 끕니다. </li><li> isomantle 히터에서 둥근 바닥 플라스크를 꺼내고 마그네타이트 겔을 보유하는 형틀의 저부에 대해 유지 강력 자석을 사용하는 동안 남아있는 액체를 가만히 따르다. 주의! 손상이나 부상을 방지하기 위해 극도의주의 강한 자석을 처리합니다. </li><li> (선택 사항) / N은 ​​공기 건조 O에 자철광 젤을 허용합니다. </li></ol> 자철광 젤 2. 정제 <ol><li> 마그네타이트 겔을 용해시키기 위해 둥근 바닥 플라스크에 헥산 40 mL로 추가 주의! 헥산 유해한 - 흄 후드에서 개인용 보호 장비는 작업을 착용하십시오. </li><li> 잔류 H 2 O를 제거하는 이리저리 탈기 H 2 O 40 mL를 분별 깔때기를 사용하여마그네타이트 용액 미터. <ol><li> 천천히 분리 깔때기 내의 H 상 자철광 솔루션 2 O을 부어 부드럽게 5 분 동안 2 상 액체 소용돌이 친다. </li><li> 밖으로 배출 및 하부 수성 부분을 폐기합니다. </li><li> 천천히 마그네타이트 용액 아래가 침전되도록 분별 깔때기로 탈기 H 2 O 40를 가하여 천천히 소용돌이 이전 드레인. </li><li> 세 번째 씻어 반복합니다. </li></ol></li><li> , 삼각 플라스크에 마그네타이트 용액을 전송 무수 황산나트륨 상당 몇 주걱을 추가 소용돌이 마그네타이트 용액에 남아있는 잔류 H 2 O를 제거 하였다. </li><li> 황산나트륨 및 잔류 H 2 O를 제거하는 필터 깔때기 1 ㎛ 여과지 마그네타이트 용액 필터 참고 : 진공 지원이 좋습니다. </li><li> 50 ㎖ 플라스크에 증발 마그네타이트 용액을 옮기고 용 헥산을 증발시켜, 회전 증발기를 사용하여다음의 조건으로 2 시간 : 중간 회전 속도, 진공을 50 ℃의 수욕을 증발 플라스크에, 도포하고, 24 ° C의 물을 순환하는 콘덴서. 참고 : 선택적으로, PLGA으로 코팅하기 전에 자철광 젤을 저장합니다. </li></ol> PLGA 셸 자철광 나노 입자의 코팅 (3) <ol><li> 1.5 % (m / v)의 용액을 만들고, 에틸 아세테이트 240 ㎖ 중의 3.60 g의 PLGA (75/25 블렌드)를 녹인다. 주의 : 에틸 아세테이트는 유해한 - 흄 후드에서 개인용 보호 장비는 작업을 착용하십시오. </li><li> 5.0 % (m / v)의 용액을 만들기 위해 자석 교반기를 사용하여 탈기 H 2 O 500ml에 플루로 닉 F-127 25.00 g을 용해. 주 : 플루로 닉 F-127은 생체 적합성 계면 활성제로 작용 비이 온성 양친 성 블록 공중 합체이다. 이 단계 3.3.2 중유 에멀젼을 안정화하는데 도움. </li><li> microspatula를 사용하여 가중 유리 병 안에 여섯 0.040 g 씩에 자철광 젤를 수집합니다. 반환 한각 나누어지는에 대한 다음과 같은 코팅 및 세척 과정을 ORM. 참고 : 분취 액을 4 단계에서 분해 이전하는 동결 건조를 최소화하면서 순도와 수율을 극대화 효율적 처리 및 자기 경사를 보장하기 위해 필요하다. <ol><li> 10 분 동안 초음파 세척기에서 0.040 g의 마그네타이트 겔의 분취 량과 플라스틱 비이커 및 초음파 처리에 PLGA 용액 40 ml를 추가하기. </li><li> 플라스틱 비이커에 플루로 닉 용액 80 ml에 첨가하고 약 7 분은 수 중유 에멀젼으로서 마그네타이트 PLGA 나노 입자에 코팅을 형성하기 위해 즉시 높은 설정으로 실험실 혼합기 유화. </li><li> 즉시 에틸 아세테이트를 증발시켜 화학 퓸 후드에서 1 시간 동안 탈 H 2 O 및 초음파 처리의 1 L에 SPION 용액을 희석. </li><li> SPION 솔루션 옆에 강력한 자석을 놓고 부드럽게 자석에 갈색 SPIONs를 수집 저어. 참고 :이 간헐적으로 몇 시간 동안 교반 할 필요가있다솔루션 전에 s는 SPIONs의 대부분은 수집 된 것을 나타내는 하얗게 변합니다. </li><li> 자석 비이커 SPIONs을 유지하면서 수용액 따르다. </li><li> 다음과 같이 SPIONs 세 번 씻으십시오. <ol><li> 탈 H 2 O 1 L에 SPIONs 일시 중단 </li><li> 20 분의 SPION 솔루션을 sonicate하세요. </li><li> SPION 솔루션 옆에 강력한 자석을 놓고 부드럽게 자석에 갈색 SPIONs를 수집 저어. 이 용액 SPIONs 대부분 수집 된 것을 나타내는 명확한 꺼질 때까지 몇 시간 동안 간헐적으로 교반 할 필요가있다. </li><li> 자석 비이커 SPIONs을 유지하면서 수용액 따르다. </li></ol></li></ol></li><li> 수성 현탁액과 같은 단일 가중 된 유리 바이알에 여섯 마그네타이트 겔 분취 각각으로부터 합성 SPIONs 수집. 필요에 따라 선택적으로 자기 여분의 물을 가만히 따르다. </li></ol> 4. 동결SPIONs의 -drying <ol><li> SPION 솔루션을 동결. </li><li> 동결 건조 동결 건조기에서 SPION 솔루션 O / N을. </li><li> 동결 건조 SPIONs 무게. 셀 라벨에 사용 전까지 동결 건조 SPIONs은 -20 ℃에서 저장 될 수있다. 참고 : -20 ° C 극적에 저장이 분해 반응 속도를 줄이고 수명을 증가시킨다. </li></ol> SPIONs와 세포의 5 라벨링 <ol><li> 40 mg / ml의 농도로 포스페이트 완충 식염수 (PBS)에 SPIONs의 분취 량을 중단하고 30 분 동안 초음파 처리. </li><li> 세포 배양 배지의 5 μL / ㎖의 농도에서 세포의 거의 합류 플라스크 SPION 용액을 추가한다. 조심스럽게 플라스크를 흔들어 균일 한 분포를 확인합니다. </li><li> 37 ° C에서 16 시간 동안 세포를 배양한다. </li><li> 부드럽게 문화 매체를 대기음하고 PBS로 두 번 세포를 씻으십시오. </li><li> 자기 표지 세포를 수집하고 실험을 위해 사용합니다. </li><li> 미사용 SPION 용액을 4 ℃에서 저장 될 수 있고, 우리되어야몇 개월 이내에 에드. 각 사용하기 전에 30 분 동안 초음파 처리. </li></ol>

<ol>
	<li>Burgess, 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=Targeted+delivery+of+neural+stem+cells+to+the+brain+using+MRI-guided+focused+ultrasound+to+disrupt+the+blood-brain+barrier.">Targeted delivery of neural stem cells to the brain using MRI-guided focused ultrasound to disrupt the blood-brain barrier.</a> PLoS One. 6 (11), e27877 (2011).</li><li>Nguyen, K. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mesenchymal+Stem+Cells+as+Targeted+Cell+Vehicles+to+Deliver+Drug-loaded+Nanoparticles+for+Cancer+Therapy.">Mesenchymal Stem Cells as Targeted Cell Vehicles to Deliver Drug-loaded Nanoparticles for Cancer Therapy.</a> J Nanomed Nanotechol. 4 (1), e128 (2013).</li><li>Kean, T. J., Lin, P., Caplan, A. I., Dennis, J. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MSCs:+Delivery+Routes+and+Engraftment,+Cell-Targeting+Strategies,+and+Immune+Modulation.">MSCs: Delivery Routes and Engraftment, Cell-Targeting Strategies, and Immune Modulation.</a> Stem Cells Int. , 732742 (2013).</li><li>Suzuki, K., 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=Targeted+cell+delivery+into+infarcted+rat+hearts+by+retrograde+intracoronary+infusion:+distribution,+dynamics,+and+influence+on+cardiac+function.">Targeted cell delivery into infarcted rat hearts by retrograde intracoronary infusion: distribution, dynamics, and influence on cardiac function.</a> Circulation. 110 (11 Suppl 1), II225-II230 (2004).</li><li>Garbern, J. C., Lee, R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+stem+cell+therapy+and+the+promise+of+heart+regeneration.">Cardiac stem cell therapy and the promise of heart regeneration.</a> Cell Stem Cell. 12 (6), 689-698 (2013).</li><li>Duckers, H. 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=Accelerated+vascular+repair+following+percutaneous+coronary+intervention+by+capture+of+endothelial+progenitor+cells+promotes+regression+of+neointimal+growth+at+long+term+follow-up:+final+results+of+the+Healing+II+trial+using+an+endothelial+progenitor+cell+capturing+stent+(Genous+R+stent).">Accelerated vascular repair following percutaneous coronary intervention by capture of endothelial progenitor cells promotes regression of neointimal growth at long term follow-up: final results of the Healing II trial using an endothelial progenitor cell capturing stent (Genous R stent).</a> EuroIntervention. 3 (3), 350-358 (2007).</li><li>Pan, Y., Du, X., Zhao, F., Xu, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Magnetic+nanoparticles+for+the+manipulation+of+proteins+and+cells.">Magnetic nanoparticles for the manipulation of proteins and cells.</a> Chem Soc Rev. 41 (7), 2912-2942 (2012).</li><li>Huang, 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=Deep+magnetic+capture+of+magnetically+loaded+cells+for+spatially+targeted+therapeutics.">Deep magnetic capture of magnetically loaded cells for spatially targeted therapeutics.</a> Biomaterials. 31 (8), 2130-2140 (2010).</li><li>Shen, 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=Comparison+of+Magnetic+Intensities+for+Mesenchymal+Stem+Cell+Targeting+Therapy+on+Ischemic+Myocardial+Repair:+High+Magnetic+Intensity+Improves+Cell+Retention+but+Has+No+Additional+Functional+Benefit.">Comparison of Magnetic Intensities for Mesenchymal Stem Cell Targeting Therapy on Ischemic Myocardial Repair: High Magnetic Intensity Improves Cell Retention but Has No Additional Functional Benefit.</a> Cell Transplant. , (2014).</li><li>Cheng, K., 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+antibody-linked+nanomatchmakers+for+therapeutic+cell+targeting.">Magnetic antibody-linked nanomatchmakers for therapeutic cell targeting.</a> Nat Commun. 5, 4880 (2014).</li><li>Vandergriff, A. C., 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+targeting+of+cardiosphere-derived+stem+cells+with+ferumoxytol+nanoparticles+for+treating+rats+with+myocardial+infarction.">Magnetic targeting of cardiosphere-derived stem cells with ferumoxytol nanoparticles for treating rats with myocardial infarction.</a> Biomaterials. 35 (30), 8528-8539 (2014).</li><li>Huang, Z., 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+targeting+enhances+retrograde+cell+retention+in+a+rat+model+of+myocardial+infarction.">Magnetic targeting enhances retrograde cell retention in a rat model of myocardial infarction.</a> Stem Cell Res Ther. 4 (6), 149 (2013).</li><li>Chaudeurge, 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=Can+magnetic+targeting+of+magnetically+labeled+circulating+cells+optimize+intramyocardial+cell+retention.">Can magnetic targeting of magnetically labeled circulating cells optimize intramyocardial cell retention.</a> Cell Transplant. 21 (4), 679-691 (2012).</li><li>Cheng, K., 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+targeting+enhances+engraftment+and+functional+benefit+of+iron-labeled+cardiosphere-derived+cells+in+myocardial+infarction.">Magnetic targeting enhances engraftment and functional benefit of iron-labeled cardiosphere-derived cells in myocardial infarction.</a> Circ Res. 106 (10), 1570-1581 (2010).</li><li>Yanai, 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=Focused+magnetic+stem+cell+targeting+to+the+retina+using+superparamagnetic+iron+oxide+nanoparticles.">Focused magnetic stem cell targeting to the retina using superparamagnetic iron oxide nanoparticles.</a> Cell Transplant. 21 (6), 1137-1148 (2012).</li><li>Ordidge, K. L., 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=Coupled+cellular+therapy+and+magnetic+targeting+for+airway+regeneration.">Coupled cellular therapy and magnetic targeting for airway regeneration.</a> Biochem Soc Trans. 42 (3), 657-661 (2014).</li><li>El Haj, A. 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=An+in+vitro+model+of+mesenchymal+stem+cell+targeting+using+magnetic+particle+labelling.">An in vitro model of mesenchymal stem cell targeting using magnetic particle labelling.</a> J Tissue Eng Regen Med. , (2012).</li><li>Vanecek, V., 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=Highly+efficient+magnetic+targeting+of+mesenchymal+stem+cells+in+spinal+cord+injury.">Highly efficient magnetic targeting of mesenchymal stem cells in spinal cord injury.</a> Int J Nanomedicine. 7, 3719-3730 (2012).</li><li>Sasaki, H., 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=Therapeutic+effects+with+magnetic+targeting+of+bone+marrow+stromal+cells+in+a+rat+spinal+cord+injury+model.">Therapeutic effects with magnetic targeting of bone marrow stromal cells in a rat spinal cord injury model.</a> Spine (Phila Pa 1976). 36 (12), 933-938 (2011).</li><li>Oshima, S., 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=Enhancement+of+bone+formation+in+an+experimental+bony+defect+using+ferumoxide-labelled+mesenchymal+stromal+cells+and+a+magnetic+targeting+system.">Enhancement of bone formation in an experimental bony defect using ferumoxide-labelled mesenchymal stromal cells and a magnetic targeting system.</a> J Bone Joint Surg Br. 92 (11), 1606-1613 (2010).</li><li>Luciani, 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=Magnetic+targeting+of+iron-oxide-labeled+fluorescent+hepatoma+cells+to+the+liver.">Magnetic targeting of iron-oxide-labeled fluorescent hepatoma cells to the liver.</a> Eur Radiol. 19 (5), 1087-1096 (2009).</li><li>Oshima, S., Kamei, N., Nakasa, T., Yasunaga, Y., Ochi, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+muscle+repair+using+human+mesenchymal+stem+cells+with+a+magnetic+targeting+system+in+a+subchronic+muscle+injury+model.">Enhancement of muscle repair using human mesenchymal stem cells with a magnetic targeting system in a subchronic muscle injury model.</a> J Orthop Sci. 19 (3), 478-488 (2014).</li><li>Ohkawa, S., 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+targeting+of+human+peripheral+blood+CD133++cells+for+skeletal+muscle+regeneration.">Magnetic targeting of human peripheral blood CD133+ cells for skeletal muscle regeneration.</a> Tissue Eng Part C Methods. 19 (8), 631-641 (2013).</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>Uthamaraj, S., 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=Design+and+validation+of+a+novel+ferromagnetic+bare+metal+stent+capable+of+capturing+and+retaining+endothelial+cells.">Design and validation of a novel ferromagnetic bare metal stent capable of capturing and retaining endothelial cells.</a> ABME. 42 (12), 2416-2424 (2014).</li><li>Polyak, B., 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=High+field+gradient+targeting+of+magnetic+nanoparticle-loaded+endothelial+cells+to+the+surfaces+of+steel+stents.">High field gradient targeting of magnetic nanoparticle-loaded endothelial cells to the surfaces of steel stents.</a> Proc Natl Acad Sci U.S.A. 105 (2), 698-703 (2008).</li><li>Pislaru, S. V., 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=Magnetically+targeted+endothelial+cell+localization+in+stented+vessels.">Magnetically targeted endothelial cell localization in stented vessels.</a> J Am Coll Cardiol. 48 (9), 1839-1845 (2006).</li><li>Pislaru, S. V., 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+forces+enable+rapid+endothelialization+of+synthetic+vascular+grafts.">Magnetic forces enable rapid endothelialization of synthetic vascular grafts.</a> Circulation. 114 (1 Suppl), 314-318 (2006).</li><li>Wang, Y. X., Xuan, S., Port, M., Idee, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+superparamagnetic+iron+oxide+nanoparticles+for+cellular+imaging+and+targeted+therapy+research.">Recent advances in superparamagnetic iron oxide nanoparticles for cellular imaging and targeted therapy research.</a> Curr Pharm Des. 19 (37), 6575-6593 (2013).</li><li>Yellen, B. B., 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=Targeted+drug+delivery+to+magnetic+implants+for+therapeutic+applications.">Targeted drug delivery to magnetic implants for therapeutic applications.</a> J Magn Magn Mater. 293 (1), 647-654 (2005).</li><li>Granot, D., 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=Clinically+viable+magnetic+poly(lactide-co-glycolide)+particles+for+MRI-based+cell+tracking.">Clinically viable magnetic poly(lactide-co-glycolide) particles for MRI-based cell tracking.</a> Magn Reson Med. , (2013).</li><li>Levy, 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=Long+term+in+vivo+biotransformation+of+iron+oxide+nanoparticles.">Long term in vivo biotransformation of iron oxide nanoparticles.</a> Biomaterials. 32 (16), 3988-3999 (2011).</li><li>Mirshafiee, V., Mahmoudi, M., Lou, K., Cheng, J., Kraft, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Protein+corona+significantly+reduces+active+targeting+yield.">Protein corona significantly reduces active targeting yield.</a> Chem Commun (Camb). 49 (25), 2557-2559 (2013).</li><li>Salvati, 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=Transferrin-functionalized+nanoparticles+lose+their+targeting+capabilities+when+a+biomolecule+corona+adsorbs+on+the+surface.">Transferrin-functionalized nanoparticles lose their targeting capabilities when a biomolecule corona adsorbs on the surface.</a> Nat Nanotechnol. 8 (2), 137-143 (2013).</li><li>Landazuri, 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=Magnetic+targeting+of+human+mesenchymal+stem+cells+with+internalized+superparamagnetic+iron+oxide+nanoparticles.">Magnetic targeting of human mesenchymal stem cells with internalized superparamagnetic iron oxide nanoparticles.</a> Small. 9 (23), 4017-4026 (2013).</li><li>Sun, J. H., 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+labeling+of+endothelial+progenitor+cells+isolated+from+peripheral+blood+with+superparamagnetic+iron+oxide+nanoparticles.">In vitro labeling of endothelial progenitor cells isolated from peripheral blood with superparamagnetic iron oxide nanoparticles.</a> Mol Med Rep. 6 (2), 282-286 (2012).</li><li>Zhang, B., 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=Detection+of+viability+of+transplanted+beta+cells+labeled+with+a+novel+contrast+agent+-+polyvinylpyrrolidone-coated+superparamagnetic+iron+oxide+nanoparticles+by+magnetic+resonance+imaging.">Detection of viability of transplanted beta cells labeled with a novel contrast agent - polyvinylpyrrolidone-coated superparamagnetic iron oxide nanoparticles by magnetic resonance imaging.</a> Contrast Media Mol Imaging. 7 (1), 35-44 (2012).</li><li>Song, 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=Labeling+efficacy+of+superparamagnetic+iron+oxide+nanoparticles+to+human+neural+stem+cells:+comparison+of+ferumoxides,+monocrystalline+iron+oxide,+cross-linked+iron+oxide+(CLIO)-NH2+and+tat-CLIO.">Labeling efficacy of superparamagnetic iron oxide nanoparticles to human neural stem cells: comparison of ferumoxides, monocrystalline iron oxide, cross-linked iron oxide (CLIO)-NH2 and tat-CLIO.</a> Korean J Radiol. 8 (5), 365-371 (2007).</li></ol>

The authors declare that they have no competing financial interests.

모든 나노 입자 합성 프로토콜로서, 화학 반응물의 순도는 최소한의 세포 독성 효과를 가질 것이다 고품질 SPIONs 달성을위한 중요하다. 이것은 올레산 (≥99 %), 철 (II) 클로라이드 수화물 (≥99.99 %), 철 (III) 클로라이드 (≥99.99 %), 에틸 아세테이트를 포함하여 매우 순수한 시약을 구입하는 것이 중요하다 (HPLC 등급, ≥99.9 % ), 헥산 (HPLC 등급, ≥97.0 %), 수산화 암모늄 (≥99.99 %) 및 ​​황산나트륨 (≥99.0...

Targeted delivery and capture of cells to specific sites within the body is desirable for a variety of biomedical applications. Delivery of neural stem cells to the brain by MRI-guided focused ultrasound has been proposed as a possible treatment option for neurodegenerative disease, traumatic brain injury, and stroke1. Mesenchymal stem cells are being studied for their ability to deliver anti-cancer drugs to tumors due to their natural tumor-tropic properties2,3. Cardiac stem cells have been delivered to the heart as a possible treatment for myocardial infarction4,5. Vascular stents have been developed with CD34 antibodies to capture circulating progenitor cells6. While promising, these cell targeting approaches present drawbacks including lack of cell specificity, inconsistent cell retention, and off-target cell delivery.
The overall goal of the current method is to enable magnetically directed targeting of cells for a variety of cell delivery and sorting applications. Magnetic targeting allows for controlled delivery of specific cells to a specific target site with minimal off-target effects7. The magnetic fields can be generated by implanted or external devices to safely direct the movement of magnetically-labeled cells within the body8. Numerous research efforts have focused on magnetically directed targeting of stem cells to injured tissues such as the heart9-14, retina15, lung16, skin17, spinal cord18,19, bone20, liver21, and muscle22,23 in order to improve regeneration outcomes.
Magnetic targeting of cells has also been studied extensively as a means to endothelialize implantable cardiovascular devices. A uniform and complete endothelium provides a barrier between the device and circulating blood elements to mitigate thrombosis and inflammation. Endothelial cells can be delivered to the device either prior to implantation or via the vascular system following implantation. In both cases, magnetic fields are used to capture cells to the surface of the device and retain the cells when subjected to the shear stress generated by circulating blood. Magnetic vascular stents24-27 and vascular grafts28 have both been fabricated and tested for this purpose.
Magnetic cell targeting requires a strategy for labeling cells with magnetic carrier particles. These particles can be bound to the surface of cells via antibodies or ligand/receptor pairs or they can be endocytosed into the cells. Superparamagnetic iron oxide nanoparticles (SPION) are biodegradable, biocompatible, and readily endocytosed by a variety of cell types29. These particles effectively render a cell responsive to magnetic fields and are naturally degraded over time. SPIONs provide a straightforward and safe means of magnetically labeling cells in culture for a variety of magnetic targeting and sorting applications. A method for synthesizing SPIONs with a magnetite (Fe3O4) core and poly(lactic-co-glycolic acid) (PLGA) shell is provided. In addition, a method for labeling cells in culture with SPIONs is provided.

<table><tbody><tr><td>Ammonium Hydroxide solution, 28% NH&lt;sub&gt;3&lt;/sub&gt; in H&lt;sub&gt;2&lt;/sub&gt;O, &amp;ge;99.99% trace metal basis</td><td>Sigma-Aldrich</td><td>338818-100ML&amp;nbsp;</td><td>Harmful reagent - wear personal protective equipment</td></tr><tr><td>Dreschel bottle, 500 ml</td><td>Ace Glass</td><td>5516-16</td><td></td></tr><tr><td>Ethyl Acetate, CHROMASOLVR Plus, for HPLC, 99.9%&amp;nbsp;</td><td>Sigma-Aldrich</td><td>650528-1L</td><td>Harmful reagent - wear personal protective equipment &amp;amp; work in fume hood</td></tr><tr><td>Ethyl alcohol</td><td>Sigma-Aldrich</td><td>E7023</td><td>Harmful reagent - wear personal protective equipment</td></tr><tr><td>Evaporating flask, 50 ml, 24/40 joint</td><td>Sigma-Aldrich</td><td>Z515558</td><td>For use with rotoevaporator</td></tr><tr><td>Filter paper, 3 cm dia, grade 1</td><td>Fisher</td><td>09-805P</td><td>For use with glass filter funnel</td></tr><tr><td>Glass beakers, 1 L</td><td>Fisher</td><td>FB-101-1000</td><td>For washing SPIONs</td></tr><tr><td>Glass filter funnel, vacuum hose adapter, fits 24/40, 30 mL</td><td>Fisher</td><td>K954100-0344&amp;nbsp;</td><td></td></tr><tr><td>Glass vial caps</td><td>Fisher</td><td>03-391-46</td><td>For use with glass vials</td></tr><tr><td>Glass vials, 2 ml</td><td>Fisher</td><td>03-391-44</td><td>For collecting magnetite gel &amp;amp; SPIONs</td></tr><tr><td>Hexane, CHROMASOLVR, for HPLC, &amp;ge;97.0% (GC)</td><td>Sigma-Aldrich</td><td>34859-1L&amp;nbsp;</td><td>Harmful reagent - wear personal protective equipment &amp;amp; work in fume hood</td></tr><tr><td>Hydrochloric acid</td><td>Sigma-Aldrich</td><td>H1758</td><td>Harmful reagent - wear personal protective equipment &amp;amp; work in fume hood</td></tr><tr><td>Iron(II) chloride tetrahydrate, &amp;ge;99.99% trace metals basis&amp;nbsp;</td><td>Sigma-Aldrich</td><td>380024-5G</td><td>Harmful reagent - wear personal protective equipment</td></tr><tr><td>Iron(III) chloride anhydrous, powder, &amp;ge;99.99% trace metals basis</td><td>Sigma-Aldrich</td><td>451649-1G</td><td>Harmful reagent - wear personal protective equipment</td></tr><tr><td>Isomantle heater, 500 mL</td><td>Voight Global</td><td>EM0500/CEX1</td><td></td></tr><tr><td>Laboratory mixer</td><td>Silverson</td><td>L5M-A</td><td></td></tr><tr><td>Lyophilizer</td><td>Labconco</td><td>7670520</td><td></td></tr><tr><td>Microspatulas</td><td>Fisher</td><td>21-401-25A</td><td>For transfering magnetite gel</td></tr><tr><td>NdFeB magnet, 1 in x 1 in x 1 in</td><td>Amazing Magnets</td><td>C1000H-M</td><td>Very strong magnet, handle with care</td></tr><tr><td>Oleic acid, &amp;ge;99% (GC)</td><td>Sigma-Aldrich</td><td>O1008-5G&amp;nbsp;</td><td>Store in freezer; Harmful reagent - wear personal protective equipment</td></tr><tr><td>Overhead stirrer</td><td>IKA</td><td>2572201</td><td></td></tr><tr><td>Overhead stirrer clamp</td><td>IKA</td><td>2664000</td><td>For use with overhead stirrer</td></tr><tr><td>Overhead stirrer H-stand</td><td>IKA</td><td>1412000</td><td>For use with overhead stirrer</td></tr><tr><td>Phosphate buffered saline</td><td>Life Technologies</td><td>10010-023</td><td></td></tr><tr><td>Plastic beakers, 250 ml</td><td>Fisher</td><td>02-591-28</td><td></td></tr><tr><td>PLGA PURASORB PDLG (75/25 blend)</td><td>Purac</td><td>PDLG 7502</td><td>PDLG 7502A may be used as well; Store in freezer</td></tr><tr><td>Pluronic F-127 powder, BioReagent, suitable for cell culture</td><td>Sigma-Aldrich</td><td>P2443-250G&amp;nbsp;</td><td></td></tr><tr><td>PTFE expandable blade paddle, 8 mm dia</td><td>SciQuip</td><td>SP4018</td><td></td></tr><tr><td>PTFE vessel adapter, fits 24/40, 8 mm dia paddle</td><td>Monmouth Scientific</td><td>PTFE Vessel Adaptor A480</td><td>For use with PTFE expandable blade paddle</td></tr><tr><td>Recirculating chiller</td><td>Clarkson</td><td>696613</td><td>For use with rotoevaporator</td></tr><tr><td>Reflux condenser, fits 24/40, 250 mm</td><td>Ace Glass</td><td>5997-133</td><td></td></tr><tr><td>Rotoevaporator</td><td>Clarkson</td><td>216949</td><td></td></tr><tr><td>Rubber septa, fits 24/40</td><td>Ace Glass</td><td>9096-56</td><td></td></tr><tr><td>Separatory funnel with stopper, 250 ml</td><td>Fisher</td><td>10-438E</td><td></td></tr><tr><td>Sodium sulfate ACS reagent, &amp;ge;99.0%, anhydrous, granular</td><td>Sigma-Aldrich</td><td>239313-500G&amp;nbsp;</td><td></td></tr><tr><td>Three neck round bottom flask, angled, 24/40 joints, 500 ml</td><td>Ace Glass</td><td>6948-16</td><td></td></tr><tr><td>Ultrasonic cleaner perforated pan</td><td>Fisher</td><td>15-335-20A</td><td>For use with ultrasonic cleaner</td></tr><tr><td>Ultrasonic cleaner, 2.8 L</td><td>Fisher</td><td>15-335-20</td><td></td></tr><tr><td>Vacuum controller</td><td>Clarkson</td><td>216639</td><td>For use with rotoevaporator (optional)</td></tr><tr><td>Vacuum pump</td><td>Clarkson</td><td>219959</td><td>For use with rotoevaporator</td></tr></tbody></table>

cell labeling and targeting with superparamagnetic iron oxide nanoparticles

세포 치료제의 표적 전달이 오프 - 표적 부위에 악영향을 최소화하면서 목표 부위에 치료 효과를 집중하여 의치 광범위한 애플리케이션 혜택 것이다. 자기 세포 타겟팅, 효율적인 안전하고 간단 전달 기술이다. 초상 자성 산화철 나노 입자 (SPION)은 생체 적합성, 생분해 성이며, 자기장에 응답들을 렌더링하기 위해 세포로 endocytosed 수있다. 합성 과정은 마그네타이트 FE (3 O 4)를 생성하는 것을 포함하는 폴리 (락트산 - 코 - 글리콜 산) (PLGA) 코팅을 형성하는 고속 유화 나노 입자. PLGA-마그네타이트 SPIONs는 약 10 nm의 직경을 포함 마그네타이트 코어 직경이 약 12​​0 나노 미터이다. 문화 매체에 배치 할 때, SPIONs 자연스럽게 세포에 의해 endocytosed 및 세포질 엔도 좀 내 작은 클러스터로 저장됩니다. 이들 입자는 세포에 충분한 질량을 부여 자성자기장 내에서 대상을 허용합니다. 수많은 세포 정렬 및 대상 응용 프로그램은 자기장에 반응하는 다양한 세포 유형을 렌더링하여 사용할 수 있습니다. SPIONs뿐만 아니라 종양 치료 또는 조직 솔더링 로컬 고열증의 의료 영상 조영제로 사용, 표적 유전자 또는 약물 전달, 진단 분석 및 생성을 포함하는 다른 생물 의학 다양한 애플리케이션을 갖는다.

마그네타이트 나노 입자는 50 ℃, 1000 rpm으로 (도 1) 및 철 (III) 클로라이드, 철 (II) 클로라이드 수화물 수용액을 교반 한 결과, 직경이 약 10 나노 미터이다. 이러한 결과는 마그네타이트 나노 입자가 성공적으로 합성을 보여준다. 이것은 처음으로 합성을 시도 할 때의 배치 작은 샘플로부터 취한 마그네타이트 나노 입자의 크기와 모양을 확인하는 것이 중요하다. 투과 전자 현미경 (TEM)?...

Watch this Scientific Journal Video about Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles at JoVE.com

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

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 ...

cell-labeling-targeting-with-superparamagnetic-iron-oxide

Research

JoVE Journal

Bioengineering

12.0K 조회수.  Mayo Clinic. 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.

비디오: Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring 

Nanomedications can be carried by blood borne monocyte-macrophages into the reticuloendothelial system (RES; spleen, liver, lymph nodes) and to end organs. The latter include the lung, RES, and brain and are operative during human immunodeficiency virus type one (HIV-1) infection. Macrophage entry into tissues is notable in areas of active HIV-1 replication and sites of inflammation. In order to assess the potential of macrophages as nanocarriers, superparamagnetic iron-oxide and/or drug laden particles coated with surfactants were parenterally injected into HIV-1 encephalitic mice. This was done to quantitatively assess particle and drug biodistribution. Magnetic resonance imaging (MRI) test results were validated by histological coregistration and enhanced image processing. End organ disease as typified by altered brain histology were assessed by MRI. The demonstration of robust migration of nanoformulations into areas of focal encephalitis provides '"proof of concept" for the use of advanced bioimaging techniques to monitor macrophage migration. Importantly, histopathological aberrations in brain correlate with bioimaging parameters making the general utility of MRI in studies of cell distribution in disease feasible. We posit that using such methods can provide a real time index of disease burden and therapeutic efficacy with translational potential to humans.

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring

Bioimaging methods used to assess cell biodistribution of nanoparticles are applicable for therapeutic and diagnostic monitoring of nanoformulated compounds. The methods described herein are sensitive and specific when assessed by histological coregistration. The methodologies provide a translational pathway from rodent to human applications.

진단 및 치료 모니터링을위한 Nanomaterials 등록 Bioimaging

Nanomedications can be carried by blood borne monocyte-macrophages into the reticuloendothelial system (RES; spleen, liver, lymph nodes) and to end ...

연구

생체공학

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 ...

의학

Labeling hESCs and hMSCs with Iron Oxide Nanoparticles for Non-Invasive in vivo Tracking with MR Imaging

In recent years, stem cell research has led to a better understanding of developmental biology, various diseases and its potential impact on regenerative medicine. A non-invasive method to monitor the transplanted stem cells repeatedly in vivo would greatly enhance our ability to understand the mechanisms that control stem cell death and identify trophic factors and signaling pathways that improve stem cell engraftment. MR imaging has been proven to be an effective tool for the in vivo depiction of stem cells with near microscopic anatomical resolution. In order to detect stem cells with MR, the cells have to be labeled with cell specific MR contrast agents. For this purpose, iron oxide nanoparticles, such as superparamagnetic iron oxide particles (SPIO), are applied, because of their high sensitivity for cell detection and their excellent biocompatibility. SPIO particles are composed of an iron oxide core and a dextran, carboxydextran or starch coat, and function by creating local field inhomogeneities, that cause a decreased signal on T2-weighted MR images. This presentation will demonstrate techniques for labeling of stem cells with clinically applicable MR contrast agents for subsequent non-invasive in vivo tracking of the labeled cells with MR imaging.

For the evaluation of new stem cell therapies it is important to non-invasively track the injected cells in vivo. This video will show you how to label human mesenchymal and embryonic stem cells with iron oxide based contrast agents in vivo for subsequent MR imaging in vivo.

이런 산화물로 hESCs과 hMSCs을 라벨링하는 MR 영상과 생체내 추적 비침습에 대한 Nanoparticles

In recent years, stem cell research has led to a better understanding of developmental biology, various diseases and its potential impact on regenerative ...

생물학

Multimodal Imaging of Stem Cell Implantation in the Central Nervous System of Mice

During the past decade, stem cell transplantation has gained increasing interest as primary or secondary therapeutic modality for a variety of diseases, both in preclinical and clinical studies. However, to date results regarding functional outcome and/or tissue regeneration following stem cell transplantation are quite diverse. Generally, a clinical benefit is observed without profound understanding of the underlying mechanism(s)1. Therefore, multiple efforts have led to the development of different molecular imaging modalities to monitor stem cell grafting with the ultimate aim to accurately evaluate survival, fate and physiology of grafted stem cells and/or their micro-environment. Changes observed in one or more parameters determined by molecular imaging might be related to the observed clinical effect. In this context, our studies focus on the combined use of bioluminescence imaging (BLI), magnetic resonance imaging (MRI) and histological analysis to evaluate stem cell grafting.
BLI is commonly used to non-invasively perform cell tracking and monitor cell survival in time following transplantation2-7, based on a biochemical reaction where cells expressing the Luciferase-reporter gene are able to emit light following interaction with its substrate (e.g. D-luciferin)8, 9. MRI on the other hand is a non-invasive technique which is clinically applicable10 and can be used to precisely locate cellular grafts with very high resolution11-15, although its sensitivity highly depends on the contrast generated after cell labeling with an MRI contrast agent. Finally, post-mortem histological analysis is the method of choice to validate research results obtained with non-invasive techniques with highest resolution and sensitivity. Moreover end-point histological analysis allows us to perform detailed phenotypic analysis of grafted cells and/or the surrounding tissue, based on the use of fluorescent reporter proteins and/or direct cell labeling with specific antibodies.
In summary, we here visually demonstrate the complementarities of BLI, MRI and histology to unravel different stem cell- and/or environment-associated characteristics following stem cell grafting in the CNS of mice. As an example, bone marrow-derived stromal cells, genetically engineered to express the enhanced Green Fluorescent Protein (eGFP) and firefly Luciferase (fLuc), and labeled with blue fluorescent micron-sized iron oxide particles (MPIOs), will be grafted in the CNS of immune-competent mice and outcome will be monitored by BLI, MRI and histology (Figure 1).

This article describes an optimized sequence of events for multimodal imaging of cellular grafts in rodent brain using: (i) in vivo bioluminescence and magnetic resonance imaging, and (ii) post mortem histological analysis. Combining these imaging modalities on a single animal allows cellular graft evaluation with high resolution, sensitivity and specificity.

마우스의 중추 신경계에서 줄기 세포 주입의 Multimodal 이미징

During the past decade, stem cell transplantation has gained increasing interest as primary or secondary therapeutic modality for a variety of diseases, ...

신경과학

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 ...

<meta charset="utf8"></head><body>쥐 교모세포종에서 영상 유도 치료 전달을 위한 산화철 나노입자

Nanoparticle Delivery of an Oligonucleotide Payload in a Glioblastoma Multiforme Animal Model

Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain malignancy for which there is no cure. The blood-brain barrier is a significant hurdle in the delivery of therapies to GBM. Reported here is an image-guided, iron oxide-based therapeutic delivery nano platform capable of bypassing this physiological barrier by virtue of size and accumulating in the tumor region, delivering its payload. This 25 nm nano platform consists of crosslinked dextran-coated iron oxide nanoparticles labeled with Cy5.5 fluorescent dye and containing antisense oligonucleotide as a payload. The magnetic iron oxide core enables tracking of the nanoparticles through in vivo magnetic resonance imaging, while Cy5.5 dye allows tracking by optical imaging. This report details the monitoring of the accumulation of this nanoparticle platform (termed MN-anti-miR10b) in orthotopically implanted glioblastoma tumors following intravenous injection. In addition, it provides insight into the in vivo delivery of RNA oligonucleotides, a problem that has hampered the translation of RNA therapeutics into the clinic.

<meta charset="utf8"></head><body>저자 스포트라이트: 교모세포종 치료를 위한 산화철 나노입자를 사용한 혁신적인 암 치료법

The blood-brain barrier is a significant hurdle in the delivery of therapies for glioblastoma, a disease for which there is no cure. Here, we report an in vivo image-guided iron oxide therapeutic nano platform that can bypass this physiological barrier by virtue of size and accumulate in the tumor.

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

Glioblastoma multiforme (GBM) is the most common and aggressive form of primary brain malignancy for which there is no cure. The blood-brain barrier is a ...

암 연구학

Using Magnetometry to Monitor Cellular Incorporation and Subsequent Biodegradation of Chemically Synthetized Iron Oxide Nanoparticles

Magnetic nanoparticles, made of iron oxide, present a peculiar interest for a wide range of biomedical applications for which they are often internalized in cells and then left within. One challenge is to assess their fate in the intracellular environment with reliable and precise methodologies. Herein, we introduce the use of the vibrating sample magnetometer (VSM) to precisely quantify the integrity of magnetic nanoparticles within cells by measuring their magnetic moment. Stem cells are first labeled with two types of magnetic nanoparticles; the nanoparticles have the same core produced via a fast and efficient microwave-based nonaqueous sol gel synthesis and differ in their coating: the commonly used citric acid molecule is compared to polyacrylic acid. The formation of 3D cell-spheroids is then achieved via centrifugation and the magnetic moment of these spheroids is measured at different times with the VSM. The obtained moment is a direct fingerprint of the nanoparticles&#8217; integrity, with decreasing values indicative of a nanoparticle degradation. For both nanoparticles, the magnetic moment decreases over culture time revealing their biodegradation. A protective effect of the polyacrylic acid coating is also shown, when compared to citric acid.

Iron oxide nanoparticles are synthesized via a nonaqueous sol gel procedure and coated with anionic short molecules or polymer. The use of magnetometry for monitoring the incorporation and biotransformations of magnetic nanoparticles inside human stem cells is demonstrated using a vibrating sample magnetometer (VSM).

자기 측정을 사용하여 화학적으로 합성된 산화철 나노 입자의 세포 통합 및 후속 생분해를 모니터링합니다.

Magnetic nanoparticles, made of iron oxide, present a peculiar interest for a wide range of biomedical applications for which they are often internalized ...

Biofunctionalization of Magnetic Nanomaterials

Magnetic nanomaterials have received great attention in different biomedical applications. Biofunctionalizing these nanomaterials with specific targeting agents is a crucial aspect to enhance their efficacy in diagnostics and treatments while minimizing the side effects. The benefit of magnetic nanomaterials compared to non-magnetic ones is their ability to respond to magnetic fields in a contact-free manner and over large distances. This allows to guide or accumulate them, while they can also be monitored. Recently, magnetic nanowires (NWs) with unique features were developed for biomedical applications. The large magnetic moment of these NWs enables a more efficient remote control of their movement by a magnetic field. This has been utilized with great success in cancer treatment, drug delivery, cell tracing, stem cell differentiation or magnetic resonance imaging. In addition, the NW fabrication by template-assisted electrochemical deposition provides a versatile method with tight control over the NW properties. Especially iron NWs and iron-iron oxide (core-shell) NWs are suitable for biomedical applications, due to their high magnetization and low toxicity.
In this work, we provide a method to biofunctionalize iron/iron oxide NWs with specific antibodies directed against a specific cell surface marker that is overexpressed in a large number of cancer cells. Since the method utilizes the properties of the iron oxide surface, it is also applicable to superparamagnetic iron oxide nanoparticles. The NWs are first coated with 3-aminopropyl-tri-ethoxy-silane (APTES) acting as a linker, which the antibodies are covalently attached to. The APTES coating and the antibody biofunctionalization are proven by electron energy loss spectroscopy (EELS) and zeta potential measurements. In addition, the antigenicity of the antibodies on the NWs is tested by using immunoprecipitation and western blot. The specific targeting of the biofunctionalized NWs and their biocompatibility are studied by confocal microscopy and a cell viability assay.

In this work, we provide a protocol to biofunctionalize magnetic nanomaterials with antibodies for specific cell targeting. As examples, we utilize iron nanowires to target cancer cells.

자성 나노 물질의 생체 기능화

Magnetic nanomaterials have received great attention in different biomedical applications. Biofunctionalizing these nanomaterials with specific targeting ...

셀 라벨 및 초상 자성 산화철 나노 입자로 타겟팅

요약

더 많은 비디오 탐색

이 비디오의 챕터

진단 및 치료 모니터링을위한 Nanomaterials 등록 Bioimaging

Ferumoxytol, FDA 승인 철 산화물 Nanoparticle과 함께 줄기 세포를 라벨링

이런 산화물로 hESCs과 hMSCs을 라벨링하는 MR 영상과 생체내 추적 비침습에 대한 Nanoparticles

마우스의 중추 신경계에서 줄기 세포 주입의 Multimodal 이미징

세포의 초고속 자화에 대한 양이온 Magnetoferritin의 합성

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

Glioblastoma multiforme animal model에서 oligonucleotide payload의 나노입자 전달

자기 측정을 사용하여 화학적으로 합성된 산화철 나노 입자의 세포 통합 및 후속 생분해를 모니터링합니다.

자성 나노 물질의 생체 기능화