This protocol allows for the reliable generation and characterization of blood outgrowth endothelial cells (BOECs) from a small volume of adult peripheral blood. BOECs can be used as a surrogate for endothelial cells from patients with vascular disorders and as a substrate for the generation of induced pluripotent stem cells.
Historically, the limited availability of primary endothelial cells from patients with vascular disorders has hindered the study of the molecular mechanisms underlying endothelial dysfunction in these individuals. However, the recent identification of blood outgrowth endothelial cells (BOECs), generated from circulating endothelial progenitors in adult peripheral blood, may circumvent this limitation by offering an endothelial-like, primary cell surrogate for patient-derived endothelial cells. Beyond their value to understanding endothelial biology and disease modeling, BOECs have potential uses in endothelial cell transplantation therapies. They are also a suitable cellular substrate for the generation of induced pluripotent stem cells (iPSCs) via nuclear reprogramming, offering a number of advantages over other cell types. We describe a method for the reliable generation, culture and characterization of BOECs from adult peripheral blood for use in these and other applications. This approach (i) allows for the generation of patient-specific endothelial cells from a relatively small volume of adult peripheral blood and (ii) produces cells that are highly similar to primary endothelial cells in morphology, cell signaling and gene expression.
Yakın zamana kadar, yeni kan damarlarının doğum sonrası kuşak önceden var olan damarların endotel hücreleri yeni damarların filizlenmesi olarak tanımlanan anjiyogenez olarak bilinen bir süreç yoluyla sadece meydana inanılırdı. 1. Bu süreç vaskülojenezde gelen tezat veya embriyojenez esnasında özel olarak meydana geldiği düşünülmektedir endotelyal progenitör kan damarlarının de novo oluşumu. 2 Bununla birlikte, daha yeni çalışmalar, tanımlanmış ve yetişkin periferal kan endotelyal progenitör hücre (EPC) dolaşımdaki izole var. Bu hücreler, kültürde olgun endotel hücrelerine dönüştürmek kapasitesine sahiptir ve doğum sonrası vaskülojenez katılma inanılmaktadır. 3,4
Izolasyon ve bu EPC genişlemesi için protokoller, tipik olarak vascul de dahil olmak üzere endotel büyüme faktörlerini ihtiva eden ortam içinde periferal kan tek-çekirdekli hücreleri (PBMNCs) kültürünü içerirar endotelyal büyüme faktörü (VEGF) ve fibroblast büyüme faktörü-2. 5-8 EPC kültürleri önemli ölçüde farklı hücre tipleri, çeşitli üretir. İlk kültürler (<7 gün) "erken" EPC olarak literatürde bilinen bir monositik hücre tipi, hakim. Kendilerine ait olmasına rağmen, bu hücreler, monosit işaretleme maddesi CD14 ifade progenitör işaretleyici CD34 için negatiftir ve klasik endotel belirteçler CD31 ve VEGF reseptör 2 (VEGFR2) sadece minimal seviyeleri ifade etmedi. 5 devam kültür hücreleri, ikinci popülasyonuna yolaçar endotel benzeri hücreler gibi gizli koloniler görünür Geç sonucudur EPC veya kan sonucudur endotel hücreleri (BOECs) olarak da bilinir. Monositik erken EPC aksine, aynı zamanda endotel koloni oluşturan hücreler (ECFCs), akıbet endotel hücrelerini ya da geç akıbet endotel hücrelerini adı olmuştur BOECs, endotel hücre mono tabakaları tipik arnavut morfolojisi gösteren ve yüzey işaretleyici son derece benzerdir5 ve gen ifadesi 9 endotel hücrelerini olgun.
Periferik kandan endotel benzeri hücrelerin üretimi özellikle de pulmoner arteriyel Hipertoni (PAH), 10 ya da von Willebrand hastalığı. 11. Önceki BOECs mevcudiyeti, endotel gibi vasküler bozukluklarla ilgili endotel hücre fonksiyon bozukluğunun çalışma için, pek çok avantaj sunar hücreler sadece doğumda umbilikal ven ölüm ya da organ nakli, veya izole edilmiş anda nakledilmiş organ elde edilebilir. Bu azaltılmış durumu kardiyovasküler bozuklukların yanı sıra, endotel hücreleri ve ya kan hücreleri veya duvar hücreleri arasındaki etkileşim hastalardan endotel hücrelerinin biyolojisi anlamak için ciddi bir sınırlama temsil etmektedir. Ayrıca, izole ve bu kaynaklardan endotel hücrelerinin saf nüfusu kültüre teknik açıdan zor ve bu yöntemlerle elde edilen hücreler sadece bir limite sergileyend proliferatif kapasitesi. BOECs nedenle hasta kaynaklı primer endotel hücrelerin izolasyonu ve kültürü için değerli bir vekil sunuyoruz.
In vitro uygulamalara ilave olarak, aynı zamanda BOECs otolog hücre nakli tedavileri de muhtemelen yararlıdır. Bu uygulamalar, 13 BOEC türetilmiş iPSCs hastalığı modelleme için kullanılabilir neovaskülarizasyonu (burada 12 ve referanslara bakın) teşvik etmek için her iki endotel hücre nakli, hem de uyarılmış pluripotent kök hücrelerinin üretilmesini (iPSCs). Içerir ve başlangıç olarak büyük potansiyel sunmaktadır otolog hücre tedavileri için malzeme. BOECs hızlı ve deri fibroblastlar daha yüksek verimlilik ile yeniden programlayın. Bundan başka, aynı zamanda BOECs translasyonel uygulamalar için uygun olacak herhangi bir teknoloji önemli bir özelliğidir karyotipik anormallikleri, serbest olan iPSCs üretimi için izin verir. Bir hasta bir kan örneği A iPSCs oluşturma yeteneğiLSO böylece yara iyileşmesi bozuklukları, ya çok genç olan hastalardan hücrelerinin üretilmesini kolaylaştıran bir cilt biyopsisi gereksinimini ve cilt fibroblast üretimini ortadan kaldırır.
Aşağıda ayrıntılı protokol tarafından onaylanan ve Ulusal Araştırma Etik Servis Komitesi (Doğu İngiltere) yönergelerine uygun olarak yapılan, nispeten küçük bir birimden% 90'dan fazla verimlilik BOECs üretimi için basit ve güvenilir bir yöntem (60 sağlar mi), periferal kan. Bu hücreler yüksek proliferatif ve tek bir kan örneğinden hücre yüz milyonlarca üretimi için izin defalarca geçişli olabilir.
We present a detailed protocol that allows for the robust and efficient derivation of BOECs from adult peripheral blood mononuclear cells (PBMNCs). Our protocol includes two important refinements that represent advances on previous methods of BOEC isolation.14-16 These include the absence of heparin in the initial PBMNC culture medium and the use of defined, embryonic stem cell-qualified serum. This latter refinement is of particular importance. Embryonic stem cell (ESC)-qualified serum is a more consistent grade of serum and, although it is not known yet what component(s) are enriched in the serum that benefit BOEC isolation, the impact of this defined serum on the efficiency of BOEC generation is clear in our hands. In addition, we have also had success in isolating BOECs using human serum, thereby allowing for the generation of BOECs for clinical translation. In our hands, this refined protocol results in the successful isolation of stable BOEC cultures from greater than 90% of donors, making it one of the most reliable BOEC generation methods reported thus far. Although the use of particular sera is critical to BOEC generation, it also represents a primary limitation of the current protocol. Future improvements to the technique could include the generation of these cells in serum-free, defined culture conditions.
Critical Steps in the protocol include processing blood samples as soon as possible after collection, complete harvesting of the buffy coat cells after density gradient centrifugation and the timely passaging of initial colonies from P0 to P1. This passaging step is critical to establishment of a stable isolation. Like other endothelial cells, BOECs appear to be very sensitive to plating density. If the plating density after passaging is too low, the BOECs will not proliferate. Conversely, if the colonies are allowed to become overconfluent before passaging, the cells will also cease to proliferate and have the tendency to convert into an elongated, mesenchymal cell phenotype. If few colonies appear from days 7 to 14, or if the colonies are small in size, troubleshooting can include increasing cell density by passaging P0 colonies into a T-25 flask instead of a T-75.
Once the technique is mastered, the resultant BOECs can be used in several applications, including in vitro studies of endothelial cell biology, disease modeling and drug screening, as well as in vivo cell transplantation therapies. An important consideration for the development of any cell therapy process is to use cells that are free from pathogenic mutations. We have previously shown that BOECs isolated using our protocol possess genomes that are free from copy number variations and are thus representative of the individual from which they were collected. In addition, we have also demonstrated that the majority of BOEC-derived iPSC lines are free from copy number variations.13 This contrasts with previous reports of copy number variation in fibroblast-derived iPSCs. To date, these cells remain the only iPSCs for which this degree of genomic fidelity has been reported. This feature is important for the field of iPSC biology and the use of iPSCs in disease modeling, drug screening and future cell transplantation therapies.
The authors have nothing to disclose.
This work was supported by grants funded by the British Heart Foundation (BHF), Dinosaur Trust, McAlpine Foundation, Fondation Leducq, Fight for Sight, the Cambridge Biomedical Research Centre, National Institute of Health Research including (i) the BHF Oxbridge Centre of Regenerative Medicine [RM/13/3/30159], (ii) the BHF Cambridge Centre of Research Excellence, (iii) Addenbrooke’s Hospital, Cambridge University Hospitals NHS Foundation Trust and (iv) Papworth Hospital NHS Foundation Trust, and supported the Cambridge NIHR BRC Cell Phenotyping Hub. MLO is funded by a BHF Intermediate Fellowship. FNK is funded by a BHF PhD Studentship.
For blood collection | |||
60 mL syringe with luer-lok tip | BD | 309653 | |
19G Surflo Winged Infusion Set | Terumo | SV-19BL | |
50 mL conical centrifuge tube | StarLab | E1450 | 2 per donor |
Sodium Citrate | Martindale Pharmaceuticals | 270541 | |
Name | Company | Catalog Number | Comments |
For buffy coat isolation | |||
Ficoll-Paque Plus | GE Healthcare | 17-1440-03 | |
Dulbecco’s PBS (without Ca2+ and Mg2+) | Sigma-Aldrich | D8537 | |
Sterile wrapped plastic transfer pipettes | Appleton Woods | KC231 | |
Turk’s Solution | Millipore | 1.093E+09 | |
Name | Company | Catalog Number | Comments |
For cell culture, passaging and freezing cells | |||
Type 1 Collagen (derived from rat tail) | BD Biosciences | 35-4236 | |
Dulbecco’s PBS (without Ca2+ and Mg2+) | Sigma-Aldrich | D8537 | |
0.02M Acetic Acid | Sigma-Aldrich | A6283 | prepared in reagent grade water |
Endothelial Growth Medium-2MV (containing Bullet Kit, but not serum) |
Lonza | CC-3202 | Note: It is essential that the medium does not contain heparin. Do not use EGM-2. |
Fetal Bovine Serum (U.S.), Defined | Hyclone | SH30070 | |
10x Trypsin EDTA | Gibco | T4174 | Dilute to 1x in PBS prior to use |
Heat Inactivated FBS | Gibco | 10500-064 | |
DMEM | Gibco | 41965-039 | |
DMSO | Sigma-Aldrich | 276855 | |
Nalgene Mr. Frosty Freezing Container | Sigma-Aldrich | C1562 | |
Name | Company | Catalog Number | Comments |
For flow cytometric characterization | |||
FITC-conjugated mouse anti-human CD14 | BD Biosciences | 555397 | Mouse IgG1k, Clone: WM59 Dilution: 1:20 |
FITC-conjugated mouse anti-human CD31 | BD Biosciences | 555445 | Mouse IgG1k, Clone: WM59 Dilution: 1:20 |
APC-conjugated mouse anti-human CD34 | BD Biosciences | 555824 | Mouse IgG1k, Clone: 581/CD34 Dilution: 1:20 |
FITC-conjugated mouse anti-human CD45 | BD Biosciences | 560976 | Mouse IgG1k, Clone: HI30 Dilution: 1:20 |
APC-conjugated mouse anti-human VEGFR2 | R&D Systems | FAB357A | Mouse IgG1, Clone: 89106 Dilution: 1:10 |
FITC-conjugated mouse IgG1k isotype control | BD Biosciences | 555748 | Clone: MOPC-21 Dilution: 1:20 |
APC-conjugated mouse IgG1k isotype control | BD Biosciences | 555751 | Clone: MOPC-21 Dilution: 1:20 |
APC-conjugated mouse IgG1k isotype control | R&D Systems | IC002A Dilution: 1:10 |
Clone: 11711 |
EDTA, 0.5M solution | Sigma-Aldrich | E7889 | |
Name | Company | Catalog Number | Comments |
For immunofluorescent microscopy | |||
Corning Costar 24-well tissue culture plate | Sigma-Aldrich | CLS3527 | |
Paraformaldehyde | Sigma-Aldrich | 158127 | |
BSA | Sigma-Aldrich | A7906 | |
Polysorbate 20 | Sigma-Aldrich | P2287 | |
Monoclonal mouse anti-human CD34 antibody | R&D Systems | MAB72271 | Clone 756510, IgG1, use at 10 μg/ml |
Polyclonal goat anti-human VE-cadherin (CD144) | R&D Systems | AF938 | Antigen affinity- purified IgG, use at 1:300 |
Monoclonal rabbit anti-human Von Willebrand Factor (vWF) | Abcam | ab154193 | Clone EPSISR15, use at 1:250 |
Donkey anti-mouse IgG (H+L) secondary antibody, Alexa Fluor 488 conjugate | Life Technologies | A-21202 | Polyclonal, 2 mg/ml, use at 1:200 |
Donkey anti-goat IgG (H+L) secondary antibody, Alexa Fluor 488 conjugate | Life Technologies | A-11055 | Polyclonal, 2 mg/ml, 1:200 |
Donkey anti-rabbit IgG (H+L) secondary antibody, Alexa Fluor 568 conjugate | Life Technologies | A-10042 | Polyclonal, 2 mg/ml, 1:200 |
DAPI (4′,6-Diamidino-2-phenylindole dihydrochloride) | Sigma-Aldrich | D9542 | use at 1 μg/ml |