El protocolo para la generación de las células B CD40-activado a partir de PBMC se divide en dos partes: la parte A demuestra la preparación de ligando de CD40 que expresa NIH/3T3 células, que se utilizará como células alimentadoras obligado placa. La parte B describe la actual CD40-B cultura. A. Preparación de las células de alimentación (tCD40L NIH/3T3) El NIH/3T3 tCD40L es un adherente línea murina de células de fibroblastos, que nunca debe ser totalmente confluente. Las células son por lo tanto, dividido dos veces por semana. El cultivo de más de más de 6 semanas no es recomendable. <ol><li> Quitar medio de edad de la cultura de primaria con una pipeta estéril y lavar las células con 10 ml de PBS 1x. Aspirar el PBS después del lavado. </li><li> Agregar 4 ml de tripsina / EDTA en un matraz de 75 cm 2 durante 5-10 minutos a 37 ° C. Use suaves golpecitos para separar las células. </li><li> Agregar 10 ml de medio de tipo salvaje y giro suave. </li><li> La transferencia de la suspensión de células en un tubo de 50 ml con una pipeta estéril y el giro de las células hacia abajo a 225 xg durante 5 min. </li><li> Eliminar el sobrenadante y resuspender el precipitado en 10 ml de medio de tipo salvaje. Cuente el número de células de una parte alícuota de la suspensión celular y preparar tres tubos de 50 ml con el número adecuado de células: <ol><li> 1,5 x 10 6 células por subcultivo </li><li> 0,2 x 10 6 células / pocillo de irradiación utilizadas para el cultivo de células CD40-B </li><li> resto de congelar (si es necesario). </li></ol></li><li> Giro de las células hacia abajo a 225 xg durante 5 min. </li><li> Eliminar el sobrenadante. <ol><li> Para subcultivo: resuspender 1,5 x 10 6 células en 10 ml de medio de tipo salvaje en un 75 cm 2 frasco de cultivo celular (densidad celular de 1,5 x 10 5 células / ml), añadir G-418 [0,7 mg / ml] e incubar las células en 37 ° C con 5% de CO 2. Dividir las células dos veces por semana. </li><li> Para el cultivo de células CD40-B: Es necesario 1,2 x 10 6 células por uno de 6 pocillos. Resuspender las células en el medio silvestre, con una densidad de 0,1 x 10 6 células / ml e irradiar a los 78 Gy. Placa de 2 ml de la suspensión celular en cada pocillo y se incuba a 37 ° C con 5% de CO 2. Utilice esta platos preparados para la estimulación de células B cuando tCD40L NIH/3T3 células adherentes (por lo menos 4 horas: comprobar el cumplimiento con el microscopio, no espere más de 24 horas para empezar la estimulación de células B). (Continuar con B.) </li></ol></li></ol> B. CD 40-B de cultivo celular I. Preparación de PBMCs de CD40-estimulación (día 0): Tenga en cuenta: antes de continuar asegurarse de que las células alimentadoras son adherentes. Siempre agregue nuevas soluciones de interleucina-4 y la ciclosporina A para el medio de cultivo inmediatamente antes del uso. <ol><li> Tome PBMCs, ya sea fresco o descongelado adecuadamente. Resuspender PBMCs dos veces en 50 ml de PBS 1x para lavar y centrifugar por primera vez a 265 g durante 7 min y una segunda vez a 190 xg durante 7 min para eliminar otras células. Desechar el sobrenadante y resuspender las células en 20 ml de PBS. Determinar el número de células en una parte alícuota de la suspensión celular. </li><li> Decantar la cantidad necesaria de células en 225 g durante 5 min. Para una placa de 6 pocillos 4 x 10 6 células / así se necesitan, por lo tanto 24 x 10 6 células por placa. </li><li> Eliminar el sobrenadante y resuspender el PBMC a 1 x 10 6 células / ml en CD40-B medio de cultivo fresco suplementado con 50 U / mL de IL-4 como un factor de crecimiento y 0,63 ciclosporina mg / ml A para prevenir la extensión de las células T (Teniendo en cuenta las concentraciones se refieren a un medio de cultivo ml!). </li><li> Eliminar el sobrenadante de 6 y placa pre-incubadas con tCD40L NIH/3T3 células. </li><li> Lave el adherente tCD40L NIH/3T3 células con 2 ml de PBS por el primer pozo y en una segunda fase con 2 ml de CD40-B medio de lavado. </li><li> Suavemente agregar 4 ml de la suspensión de PBMC (1 x 10 6 células / ml) a cada pocillo de la placa de 6 pocillos. </li><li> Se incuban las células a 37 º C con CO2 al 5%. </li><li> El día 7, reculture las células (Continúe con 3.2.). </li></ol> II. Nueva puesta en cultivo de células CD40-B (día 7, y después cada 3-4 días): <ol><li> Racimos de la cosecha de células B CD40-de 6 y placa resuspendiendo con una pipeta de 10 ml y la piscina que en un tubo de 50 ml. </li><li> Centrifugar a 225 xg durante 7 minutos y sustituir por completo el sobrenadante con CD40-B medio de lavado. Al contar la cantidad de células de una parte alícuota, girar las células hacia abajo a 225 xg durante 5 minutos. Resuspender las células CD40-B CD40-B en el medio de cultivo a una concentración de 1 x 10 6 células / ml. </li><li> Añadir nuevas soluciones de interleucina-4 en una concentración de 50 U / mL y 0,63 mg / ml de ciclosporina A en el medio. </li><li> Eliminar el sobrenadante de una placa de 6 pocillos pre-incubadas con tCD40L NIH/3T3 células. </li><li> Lave las células adherentes con 2 ml de PBS por pocillo primera y en una segunda fase con 2 ml de CD40-B medio de lavado. </li><li&gt; Suavemente agregar 4 ml (1 x 10 6 células / ml) de suspensión CD40-B a cada pocillo de la placa de 6 pocillos. </li><li> Incubar las placas a 37 ° C con 5% de CO 2. </li><li> Las células de la subcultura de nuevo cada 3-4 días para terminar con las células humanas de alta pureza B CD40-activa después de un total de 14 días. </li></ol> C. Solución de problemas - ¿Qué pasa si las células CD40-B no crecen? <ol><li> ¿Ha revisado para la expresión del ligando CD40 de células alimentadoras? </li><li> La placa con destino células alimentadoras utiliza para la estimulación no debe ser mayor de 24 horas? </li><li> Es una contaminación por micoplasma es posible? </li><li> Era la solución de interleuquina-4 utilizado para la suplementación recién descongelado y tuvo la actividad biológica apropiada? </li><li> Se añade la ciclosporina A en la concentración correcta? </li></ol><img src="/files/ftp_upload/1373/1373fig1tmb.jpg" border="0" alt="Figura 1" /> Figura 1. Por favor, <a href="https://www.jove.com/files/ftp_upload/1373/1373fig1.jpg">haga clic aquí</a> para una versión ampliada de la figura 1. <img src="/files/ftp_upload/1373/1373fig2tmb.jpg" border="0" alt="Figura 2" /> Figura 2. Por favor, <a href="https://www.jove.com/files/ftp_upload/1373/1373fig2.jpg">haga clic aquí</a> para una versión ampliada de la figura 2.

<ol>
	<li>Schultze, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD40-activated+human+B+cells:+an+alternative+source+of+highly+efficient+antigen+presenting+cells+to+generate+autologous+antigen-specific+T+cells+for+adoptive+immunotherapy.">CD40-activated human B cells: an alternative source of highly efficient antigen presenting cells to generate autologous antigen-specific T cells for adoptive immunotherapy.</a> J Clin Invest. 100, 2757-2765 (1997).</li><li>Schultze, J. L., Grabbe, S., vonBergwelt-Baildon, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DCs+and+CD40-activated+B+cells:+current+and+future+avenues+to+cellular+cancer+immunotherapy.">DCs and CD40-activated B cells: current and future avenues to cellular cancer immunotherapy.</a> Trends Immunol. 25, 659-664 (2004).</li><li>Bergwelt-Baildon, M. v. o. n. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD40-activated+B+cells+express+full+lymph+node+homing+triad+and+induce+T-cell+chemotaxis:+potential+as+cellular+adjuvants.">CD40-activated B cells express full lymph node homing triad and induce T-cell chemotaxis: potential as cellular adjuvants.</a> Blood. 107, 2786-2789 (2006).</li><li>Wiesner, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Conditional+immortalization+of+human+B+cells+by+CD40+ligation.">Conditional immortalization of human B cells by CD40 ligation.</a> PLoS ONE. 3, 1464-14 (2008).</li><li>Urashima, M., Chauhan, D., Uchiyama, H., Freeman, G. J., Anderson, K. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD40+ligand+triggered+interleukin-6+secretion+in+multiple+myeloma.">CD40 ligand triggered interleukin-6 secretion in multiple myeloma.</a> Blood. 85, 1903-1912 (1995).</li><li>Lapointe, R., Bellemare-Pelletier, A., Housseau, F., Thibodeau, J., Hwu, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD40-stimulated+B+lymphocytes+pulsed+with+tumor+antigens+are+effective+antigen-presenting+cells+that+can+generate+specific+T+cells.">CD40-stimulated B lymphocytes pulsed with tumor antigens are effective antigen-presenting cells that can generate specific T cells.</a> Cancer Res. 63, 2836-2843 (2003).</li><li>von Bergwelt-Baildon, M. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Human+primary+and+memory+cytotoxic+T+lymphocyte+responses+are+efficiently+induced+by+means+of+CD40-activated+B+cells+as+antigen-presenting+cells:+potential+for+clinical+application.">Human primary and memory cytotoxic T lymphocyte responses are efficiently induced by means of CD40-activated B cells as antigen-presenting cells: potential for clinical application.</a> Blood. 99, 3319-3325 (2002).</li><li>Kondo, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CD40-activated+B+cells+can+be+generated+in+high+number+and+purity+in+cancer+patients:+analysis+of+immunogenicity+and+homing+potential.">CD40-activated B cells can be generated in high number and purity in cancer patients: analysis of immunogenicity and homing potential.</a> Clin Exp Immunol. 155, 249-256 (2009).</li><li>Mason, N. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=RNA-loaded+CD40-activated+B+cells+stimulate+antigen-specific+T-cell+responses+in+dogs+with+spontaneous+lymphoma.">RNA-loaded CD40-activated B cells stimulate antigen-specific T-cell responses in dogs with spontaneous lymphoma.</a> Gene Ther. 15, 955-965 (2008).</li></ol>

A. Preparación de los medios de comunicación: <table border="1"cellspacing="0"><tbody><tr><td colspan="2"> Alimentador de medio celular de tipo salvaje </td><td colspan="2"> Alimentador de selección de células medianas </td></tr><tr><td> Reactivo </td><td> Concentración </td><td> Reactivo </td><td> Concentración </td></tr><tr><td> DMEM-Cam / F12 </td><td></td><td> DMEM-Cam / F12 </td><td></td></tr><tr><td> L-Glutamina </td><td> 365 mg / ml </td><td> L-Glutamina </td><td> 365 mg / ml </td></tr><tr><td> FBS </td><td> 10% </td><td> FBS </td><td> 10% </td></tr><tr><td> HEPES </td><td> 10 mM </td><td> HEPES </td><td> 10 mM </td></tr><tr><td> Gentamicina </td><td> 15 mg / ml </td><td> Gentamicina </td><td> 15 mg / ml </td></tr><tr><td></td><td></td><td> G-418 </td><td> 0,7 mg / ml </td></tr></table><table cellspacing="0" border="1"><tbody><tr><td colspan="2"> CD40-B medio de lavado </td><td colspan="2"> CD40-B medio de cultivo </td></tr><tr><td> Reactivo </td><td> Concentración </td><td> Reactivo </td><td> Concentración </td></tr><tr></tr></tbody><tbody><tr><td> IMDM </td><td> </td><td> IMDM </td><td> </td></tr></tbody><tbody><tr><td> L-Glutamina </td><td> 584 mg / ml </td><td> L-Glutamina </td><td> 584 mg / ml </td></tr></tbody><tbody><tr><td> HEPES </td><td> 25 mM </td><td> HEPES </td><td> 25 mM </td></tr></tbody><tbody><tr><td> Gentamicina </td><td> 15 mg / ml </td><td> Gentamicina </td><td> 15 mg / ml </td></tr></tbody><tbody><tr><td> </td><td> </td><td> rh transferrina </td><td> 50 mg / ml </td></tr></tbody><tbody><tr><td> </td><td> </td><td> La insulina rh </td><td> 5 mg / ml </td></tr></tbody><tbody><tr><td> </td><td> </td><td> AB-Humanserum </td><td> 10% </td></tr></tbody></table> B. Otros reactivos: <table cellspacing="0" border="1"><tbody><tr><td> Reactivo </td><td> Empresa </td><td> El número de orden </td></tr><tr></tr><tr><td> DMEM / Ham F12 </td><td> PAA </td><td> Ningún gato: E15-813 </td></tr><tr><td> IMDM </td><td> Invitrogen Gibco ® </td><td> REF 21980-032 </td></tr><tr><td> Dulbecco PBS (10x) </td><td> PAA </td><td> No gato H15-011 </td></tr><tr><td> AB-suero humano </td><td> Invitrogen </td><td> Gato No 34005100 </td></tr><tr><td> holo-transferrina humana </td><td> Sigma </td><td> Gato No T0665 </td></tr><tr><td> La insulina humana </td><td> Sigma </td><td> Gato No I2643 </td></tr><tr><td> Gencin ® </td><td> Seleccione Delta </td><td> Arte No 7395800 </td></tr><tr><td> La interleucina-4 humana recombinante </td><td> Immunotools </td><td> Gato No 11130045 </td></tr><tr><td> La ciclosporina A </td><td> Novartis </td><td> No NDC 0078-0109-01 gato </td></tr><tr><td> FBS </td><td> LONZA </td><td> Gato No DE14-802C </td></tr><tr><td> Tampón HEPES </td><td> PAA </td><td> No gato S11-001 </td></tr><tr><td> G-418 Sulfato </td><td> PAA </td><td> No gato P02-012 </td></tr><tr><td> Tripsina / EDTA (10 veces) </td><td> Invitrogen Gibco ® </td><td> REF 15400-054 </td></tr></tbody></table> C. Otros materiales: <table cellspacing="0" border="1"><tbody><tr><td> Reactivo </td><td> Empresa </td><td> El número de orden </td></tr><tr></tr><tr><td> Puntas de pipeta estériles </td><td> Sarstedt </td><td></td></tr><tr><td> 6 y placa </td><td> NUNC </td><td> Gato No 140675 </td></tr><tr><td> Tubo cónico de 50 ml </td><td> BD Falcon ™ </td><td> Gato No 352070 </td></tr><tr><td> Frasco de cultivo de tejidos </td><td> SARSTEDT </td><td> Gato No 83.1813.002 </td></tr></tbody></table>

generation of human cd40-activated b cells

CD40-activa las células B (CD40-células B) se han identificado como una fuente alternativa de presentadoras de antígeno inmuno-estimulantes de las células (APC) para la inmunoterapia del cáncer 1-3. Comparación con las células dendríticas (CDs), la mejor caracterizada APC, las células CD40-B tienen varias propiedades diferentes biológicos y técnicos. Al igual que en los países en desarrollo, las células B muestran un incremento en la expresión de MHC y moléculas co-estimulantes (Fig.1b), muestran una gran capacidad migratoria y la presentación de antígenos presentes de manera eficiente a las células T, después de la estimulación con el ligando interleucina-4 y CD40 (CD40L). Sin embargo, en contraste con los países en desarrollo inmaduro o maduro, las células CD40-B expresan la tríada de los ganglios linfáticos completa mensajeras que consta de CD62L, CCR7/CXCR4, y la función leucocitaria antígeno-1 (LFA1, CD11a/CD18), necesarios para la recalada de los órganos linfoides secundarios (Fig. 1A) 3. Las células CD40-B se puede generar sin problemas de cantidades muy pequeñas de sangre periférica, que puede ser ampliado in vitro a cantidades muy grandes de muy pura CD40-células B (&gt; 10 9 células por paciente) de donantes sanos, así como el cáncer pacientes (Fig. 1c, d) 1,4. En este protocolo se demuestra cómo obtener completamente activados CD40-células B a partir de PBMC humanos. Moléculas clave para el cultivo de células son CD40 ligando, la interleucina-4 (IL-4) y ciclosporina A (CsA), que se renuevan en un ciclo de día y la cultura 4.3. Para fines de laboratorio CD40-estimulación es proporcionado por NIH/3T3 células que expresan el ligando CD40 humano recombinante (tCD40L NIH/3T3) 5. Para evitar la contaminación con células no transfectadas, la expresión del ligando de CD40 humano en los transfectantes tiene que ser revisado regularmente (Fig. 2). Después de 14 días CD40-B consisten en cultivos celulares de más del 95% de pureza células B y la expansión de células B CD40-más de 65 días es con frecuencia posible sin ningún tipo de pérdida de la función 1, 4. Las células CD40-B de manera eficiente recoger, procesar y 6 presentan antígenos a las células T. No sólo naϊve principal, sino también ampliar las células T de memoria 7,8. CD40-activa las células B puede ser usado para estudiar la activación de células B, diferenciación y función. Además, representan una herramienta prometedora para la vacunación terapéutica o preventiva contra los tumores 9.

Watch this Scientific Journal Video about Generation of Human CD40-activated B cells at JoVE.com

Generation of Human CD40-activated B cells

En este video se presenta la<em&gt; Ex vivo</em&gt; Generación y ampliación de los derechos humanos CD40-activa las células B (CD40-B) a partir de células mononucleares de sangre periférica (CMSP) por la estimulación con el ligando CD40 y la interleucina-4.

Generación de humanos CD40 activado por células B

CD40-activated B cells (CD40-B cells) have been identified as an alternative source of immuno-stimulatory antigen-presenting cells (APC) for cancer ...

generation-of-human-cd40-activated-b-cells

Research

JoVE Journal

Biology

15.1K vistas.  University Hospital of Cologne, Department I of Internal Medicine. En este video se presenta la Ex vivo Generación y ampliación de los derechos humanos CD40-activa las células B (CD40-B) a partir de células mononucleares de sangre periférica (CMSP) por la estimulación con el ligando CD40 y la interleucina-4.

Video: Generation of Human CD40-activated B cells

Chromosomal Spread Preparation of Human Embryonic Stem Cells for Karyotyping

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture conditions they become prone to acquire chromosomal anomalies such as addition of whole or parts of chromosomes. Indeed, during long-term culture, karyotypic alterations are observed when enzymatic or chemical dissociation are used 2,3,4, while manual dissection of colonies for passaging retains a stable karyotype 5. Besides, changes in the environment such as the removal of feeder cells also seem to compromise the genetic integrity of hESC 3,6. Once chromosomal alterations could affect cellular physiology, the characterization of the genetic integrity of hESC in vitro is crucial considering hESC as an essential tool in embryogenesis studies and drug testing. Furthermore, for future therapeutic purposes chromosomal changes are a real concern as it is frequently associated to carcinogenesis.
Here we show a simple and useful method to obtain high quality chromosome spreads for subsequent analysis of chromosome set by G-banding, FISH, SKY or CGH techniques 7,8. We recommend checking the chromosomal status routinely with intervals of 5 passages in order to monitor the appearance of translocations and aneuploidies
Priscila Britto and Rafaela Sartore contributed equally to the paper.

Karyotyping is a simple and useful technique widely used for detecting genetic alterations. Here we describe a step by step protocol for chromosome spread preparation of human embryonic stem cells for monitoring the chromosomal status of these cells maintained in culture.

Preparación Extienda los cromosomas de las células estaminales embrionarias para cariotipo

Although human embryonic stem cells (hESC) have been shown to present a stable diploid karyotype 1, many studies have reported that depending on culture ...

Investigación

Biología

Generation of Induced Pluripotent Stem Cells by Reprogramming Human Fibroblasts with the Stemgent Human TF Lentivirus Set

In 2006, Yamanaka and colleagues first demonstrated that retrovirus-mediated delivery and expression of Oct4, Sox2, c-Myc and Klf4 is capable of inducing the pluripotent state in mouse fibroblasts.1 The same group also reported the successful reprogramming of human somatic cells into induced pluripotent stem (iPS) cells using human versions of the same transcription factors delivered by retroviral vectors.2 Additionally, James Thomson et al. reported that the lentivirus-mediated co-expression of another set of factors (Oct4, Sox2, Nanog and Lin28) was capable of reprogramming human somatic cells into iPS cells.3
iPS cells are similar to ES cells in morphology, proliferation and the ability to differentiate into all tissue types of the body. Human iPS cells have a distinct advantage over ES cells as they exhibit key properties of ES cells without the ethical dilemma of embryo destruction. The generation of patient-specific iPS cells circumvents an important roadblock to personalized regenerative medicine therapies by eliminating the potential for immune rejection of non-autologous transplanted cells.
Here we demonstrate the protocol for reprogramming human fibroblast cells using the Stemgent Human TF Lentivirus Set. We also show that cells reprogrammed with this set begin to show iPS morphology four days post-transduction. Using the Stemolecule Y27632, we selected for iPS cells and observed correct morphology after three sequential rounds of colony picking and passaging. We also demonstrate that after reprogramming cells displayed the pluripotency marker AP, surface markers TRA-1-81, TRA-1-60, SSEA-4, and SSEA-3, and nuclear markers Oct4, Sox2 and Nanog.

We demonstrate the protocol for the generation of induced pluripotent stem cells from human somatic cells using lentivirus-mediated delivery of the human factors Oct4, Sox2, Nanog, and Lin28. Pluripotency was confirmed by morphology and the presence of embryonic stem (ES) cell-specific markers.

Generación de células madre pluripotentes inducidas por reprogramación de fibroblastos humanos con los Lentivirus Stemgent Humanos TF Set

In 2006, Yamanaka and colleagues first demonstrated that retrovirus-mediated delivery and expression of Oct4, Sox2, c-Myc and Klf4 is capable of inducing ...

Robust Generation of Hepatocyte-like Cells from Human Embryonic Stem Cell Populations

Despite progress in modelling human drug toxicity, many compounds fail during clinical trials due to unpredicted side effects. The cost of clinical studies are substantial, therefore it is essential that more predictive toxicology screens are developed and deployed early on in drug development (Greenhough et al 2010). Human hepatocytes represent the current gold standard model for evaluating drug toxicity, but are a limited resource that exhibit variable function. Therefore, the use of immortalised cell lines and animal tissue models are routinely employed due to their abundance. While both sources are informative, they are limited by poor function, species variability and/or instability in culture (Dalgetty et al 2009). Pluripotent stem cells (PSCs) are an attractive alternative source of human hepatocyte like cells (HLCs) (Medine et al 2010). PSCs are capable of self renewal and differentiation to all somatic cell types found in the adult and thereby represent a potentially inexhaustible source of differentiated cells. We have developed a procedure that is simple, highly efficient, amenable to automation and yields functional human HLCs (Hay et al 2008 ; Fletcher et al 2008 ; Hannoun et al 2010 ; Payne et al 2011 and Hay et al 2011). We believe our technology will lead to the scalable production of HLCs for drug discovery, disease modeling, the construction of extra-corporeal devices and possibly cell based transplantation therapies.

This article will focus on the generation of human hepatic endoderm from human embryonic stem cell populations.

Generación robusta de hepatocitos como las células de las poblaciones humanas células madre embrionarias

Despite progress in modelling human drug toxicity, many compounds fail during clinical trials due to unpredicted side effects. The cost of clinical ...

Phenotypic and Functional Characterization of Endothelial Colony Forming Cells Derived from Human Umbilical Cord Blood

Longstanding views of new blood vessel formation via angiogenesis, vasculogenesis, and arteriogenesis have been recently reviewed1. The presence of circulating endothelial progenitor cells (EPCs) were first identified in adult human peripheral blood by Asahara et al. in 1997 2 bringing an infusion of new hypotheses and strategies for vascular regeneration and repair. EPCs are rare but normal components of circulating blood that home to sites of blood vessel formation or vascular remodeling, and facilitate either postnatal vasculogenesis, angiogenesis, or arteriogenesis largely via paracrine stimulation of existing vessel wall derived cells3. No specific marker to identify an EPC has been identified, and at present the state of the field is to understand that numerous cell types including proangiogenic hematopoietic stem and progenitor cells, circulating angiogenic cells, Tie2+ monocytes, myeloid progenitor cells, tumor associated macrophages, and M2 activated macrophages participate in stimulating the angiogenic process in a variety of preclinical animal model systems and in human subjects in numerous disease states4, 5. Endothelial colony forming cells (ECFCs) are rare circulating viable endothelial cells characterized by robust clonal proliferative potential, secondary and tertiary colony forming ability upon replating, and ability to form intrinsic in vivo vessels upon transplantation into immunodeficient mice6-8. While ECFCs have been successfully isolated from the peripheral blood of healthy adult subjects, umbilical cord blood (CB) of healthy newborn infants, and vessel wall of numerous human arterial and venous vessels 6-9, CB possesses the highest frequency of ECFCs7 that display the most robust clonal proliferative potential and form durable and functional blood vessels in vivo8, 10-13. While the derivation of ECFC from adult peripheral blood has been presented14, 15, here we describe the methodologies for the derivation, cloning, expansion, and in vitro as well as in vivo characterization of ECFCs from the human umbilical CB.

Endothelial colony forming cells (ECFCs) are circulating endothelial cells with robust clonal proliferative potential that display intrinsic in vivo vessel forming ability. Phenotypic and functional characterization of outgrowth endothelial cells derived from CB are important to identify and isolate bona fide ECFCs for potential clinical application in repairing damaged tissues.

Caracterización fenotípica y funcional de las células endoteliales Formadoras de Colonias derivados de la sangre del cordón umbilical

Longstanding views of new blood vessel formation via angiogenesis, vasculogenesis, and arteriogenesis have been recently reviewed1. The presence of ...

Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Using the STEMCCA Lentiviral Vector

Through the ectopic expression of four transcription factors, Oct4, Klf4, Sox2 and cMyc, human somatic cells can be converted to a pluripotent state, generating so-called induced pluripotent stem cells (iPSCs)1-4. Patient-specific iPSCs lack the ethical concerns that surround embryonic stem cells (ESCs) and would bypass possible immune rejection. Thus, iPSCs have attracted considerable attention for disease modeling studies, the screening of pharmacological compounds, and regenerative therapies5.
We have shown the generation of transgene-free human iPSCs from patients with different lung diseases using a single excisable polycistronic lentiviral Stem Cell Cassette (STEMCCA) encoding the Yamanaka factors6. These iPSC lines were generated from skin fibroblasts, the most common cell type used for reprogramming. Normally, obtaining fibroblasts requires a skin punch biopsy followed by expansion of the cells in culture for a few passages. Importantly, a number of groups have reported the reprogramming of human peripheral blood cells into iPSCs7-9. In one study, a Tet inducible version of the STEMCCA vector was employed9, which required the blood cells to be simultaneously infected with a constitutively active lentivirus encoding the reverse tetracycline transactivator. In contrast to fibroblasts, peripheral blood cells can be collected via minimally invasive procedures, greatly reducing the discomfort and distress of the patient. A simple and effective protocol for reprogramming blood cells using a constitutive single excisable vector may accelerate the application of iPSC technology by making it accessible to a broader research community. Furthermore, reprogramming of peripheral blood cells allows for the generation of iPSCs from individuals in which skin biopsies should be avoided (i.e. aberrant scarring) or due to pre-existing disease conditions preventing access to punch biopsies.
Here we demonstrate a protocol for the generation of human iPSCs from peripheral blood mononuclear cells (PBMCs) using a single floxed-excisable lentiviral vector constitutively expressing the 4 factors. Freshly collected or thawed PBMCs are expanded for 9 days as described10,11 in medium containing ascorbic acid, SCF, IGF-1, IL-3 and EPO before being transduced with the STEMCCA lentivirus. Cells are then plated onto MEFs and ESC-like colonies can be visualized two weeks after infection. Finally, selected clones are expanded and tested for the expression of the pluripotency markers SSEA-4, Tra-1-60 and Tra-1-81. This protocol is simple, robust and highly consistent, providing a reliable methodology for the generation of human iPSCs from readily accessible 4 ml of blood.

Here we show a simple and effective protocol for the generation of human iPSCs from 3-4 ml of peripheral blood using a single lentiviral reprogramming vector. Reprogramming of readily available blood cells promises to accelerate the utilization of iPSC technology by making it accessible to a broader research community.

Generación de las células madre pluripotentes inducidas a partir de sangre periférica mediante el STEMCCA vector lentiviral

Through the ectopic expression of four transcription factors, Oct4, Klf4, Sox2 and cMyc, human somatic cells can be converted to a pluripotent state, ...

Generation of Dispersed Presomitic Mesoderm Cell Cultures for Imaging of the Zebrafish Segmentation Clock in Single Cells

Segmentation is a periodic and sequential morphogenetic process in vertebrates. This rhythmic formation of blocks of tissue called somites along the body axis is evidence of a genetic oscillator patterning the developing embryo. In zebrafish, the intracellular clock driving segmentation is comprised of members of the Her/Hes transcription factor family organized into negative feedback loops. We have recently generated transgenic fluorescent reporter lines for the cyclic gene her1 that recapitulate the spatio-temporal pattern of oscillations in the presomitic mesoderm (PSM). Using these lines, we developed an in vitro culture system that allows real-time analysis of segmentation clock oscillations within single, isolated PSM cells. By removing PSM tissue from transgenic embryos and then dispersing cells from oscillating regions onto glass-bottom dishes, we generated cultures suitable for time-lapse imaging of fluorescence signal from individual clock cells. This approach provides an experimental and conceptual framework for direct manipulation of the segmentation clock with unprecedented single-cell resolution, allowing its cell-autonomous and tissue-level properties to be distinguished and dissected.

Somitogenesis is a rhythmic developmental process that spatially patterns the body axis of vertebrate embryos. Previously, we developed transgenic zebrafish lines that use fluorescent reporters to observe the cyclic genes that drive this process. Here, we culture dispersed cells from these lines and image their oscillations over time in vitro.

Generación de Dispersed presomitic mesodermo Cultivos Celulares for Imaging del pez cebra Segmentación del Reloj en células individuales

Segmentation is a  periodic and sequential morphogenetic process in vertebrates. This rhythmic  formation of blocks of tissue called somites along the ...

Generation of Human Cardiomyocytes: A Differentiation Protocol from Feeder-free Human Induced Pluripotent Stem Cells

In order to investigate the events driving heart development and to determine the molecular mechanisms leading to myocardial diseases in humans, it is essential first to generate functional human cardiomyocytes (CMs). The use of these cells in drug discovery and toxicology studies would also be highly beneficial, allowing new pharmacological molecules for the treatment of cardiac disorders to be validated pre-clinically on cells of human origin. Of the possible sources of CMs, induced pluripotent stem (iPS) cells are among the most promising, as they can be derived directly from readily accessible patient tissue and possess an intrinsic capacity to give rise to all cell types of the body 1. Several methods have been proposed for differentiating iPS cells into CMs, ranging from the classical embryoid bodies (EBs) aggregation approach to chemically defined protocols 2,3. In this article we propose an EBs-based protocol and show how this method can be employed to efficiently generate functional CM-like cells from feeder-free iPS cells.

Pluripotent stem cells, either embryonic or induced pluripotent stem (iPS) cells, constitute a valuable source of human differentiated cells, including cardiomyocytes. Here, we will focus on cardiac induction of iPS cells, showing how to use them to obtain functional human cardiomyocytes through an embryoid bodies-based protocol.

La generación de cardiomiocitos humanos: Protocolo de diferenciación de células madre pluripotentes inducidas humanas Feeder libres

In order to investigate the events driving heart development and to determine the molecular mechanisms leading to myocardial diseases in humans, it is ...

Efficient Generation Human Induced Pluripotent Stem Cells from Human Somatic Cells with Sendai-virus

A few years ago, the establishment of human induced pluripotent stem cells (iPSCs) ushered in a new era in biomedicine. Potential uses of human iPSCs include modeling pathogenesis of human genetic diseases, autologous cell therapy after gene correction, and personalized drug screening by providing a source of patient-specific and symptom relevant cells. However, there are several hurdles to overcome, such as eliminating the remaining reprogramming factor transgene expression after human iPSCs production. More importantly, residual transgene expression in undifferentiated human iPSCs could hamper proper differentiations and misguide the interpretation of disease-relevant in vitro phenotypes. With this reason, integration-free and/or transgene-free human iPSCs have been developed using several methods, such as adenovirus, the piggyBac system, minicircle vector, episomal vectors, direct protein delivery and synthesized mRNA. However, efficiency of reprogramming using integration-free methods is quite low in most cases.
Here, we present a method to isolate human iPSCs by using Sendai-virus (RNA virus) based reprogramming system. This reprogramming method shows consistent results and high efficiency in cost-effective manner.

Here, we present our established method to reprogram human somatic cells into transgene-free human iPSCs with Sendai virus, which shows consistent outcome and enhanced efficiency.

Eficiente generación, por actividad humana células madre pluripotentes de células somáticas humanas con virus Sendai-

A few years ago, the establishment of human induced pluripotent stem cells (iPSCs) ushered in a new era in biomedicine. Potential uses of human iPSCs ...

Generation and Culture of Blood Outgrowth Endothelial Cells from Human Peripheral Blood

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.

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.

Generación y Cultura de Sangre Consecuencia endoteliales Las células de la sangre periférica humana

Historically, the limited availability of primary endothelial cells from patients with vascular disorders has hindered the study of the molecular ...

High-throughput CRISPR Vector Construction and Characterization of DNA Modifications by Generation of Tomato Hairy Roots

Targeted DNA mutations generated by vectors with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology have proven useful for functional genomics studies. While most cloning strategies are simple to perform, they generally use multiple steps and can require several days to generate the ultimate constructs. The method presented here is based on DNA assembly and can produce fully functional CRISPR vectors in a single cloning reaction. Vector construction can also be pooled, further increasing the efficiency and utility of the process. A modification of the method is used to create CRISPR vectors with multiple gene targets. CRISPR vectors are then transformed into tomato hairy roots to generate transgenic materials with targeted DNA modifications. Hairy roots are a useful system for testing vector functionality as they are technically simple to generate and amenable to large-scale production. The methods presented here will have wide application as they can be used to generate a variety of CRISPR vectors and be used in a wide range of plant species.

Using DNA assembly, multiple CRISPR vectors can be constructed in parallel in a single cloning reaction, making the construction of large numbers of CRISPR vectors a simple task. Tomato hairy roots are an excellent model system to validate CRISPR vectors and generate mutant materials.

De alto rendimiento CRISPR vector de la construcción y caracterización de las modificaciones del ADN mediante la generación de raíces peludas tomate

Targeted DNA mutations generated by vectors with clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology have proven useful for ...