Summary

Stabiliser hépatocellulaire phénotype en utilisant des surfaces synthétiques optimisés

Published: September 26, 2014
doi:

Summary

This article will focus on developing polymer coated surfaces for long-term, stable culture of stem cell derived human hepatocytes.

Abstract

Currently, one of the major limitations in cell biology is maintaining differentiated cell phenotype. Biological matrices are commonly used for culturing and maintaining primary and pluripotent stem cell derived hepatocytes. While biological matrices are useful, they permit short term culture of hepatocytes, limiting their widespread application. We have attempted to overcome the limitations using a synthetic polymer coating. Polymers represent one of the broadest classes of biomaterials and possess a wide range of mechanical, physical and chemical properties, which can be fine-tuned for purpose. Importantly, such materials can be scaled to quality assured standards and display batch-to-batch consistency. This is essential if cells are to be expanded for high through-put screening in the pharmaceutical testing industry or for cellular based therapy. Polyurethanes (PUs) are one group of materials that have shown promise in cell culture. Our recent progress in optimizing a polyurethane coated surface, for long-term culture of human hepatocytes displaying stable phenotype, is presented and discussed.

Introduction

Les matières biologiques ont été largement utilisés dans l'entretien et la différenciation des cellules souches pluripotentes 1. Tout en permettant, ces substrats biologiques contiennent souvent une multitude de composants définis. Matrigel est un substrat communément utilisé pour la culture de cellules souches et de la différenciation. Malheureusement, sa composition variable influe sur la fonction des cellules et le phénotype. Bien qu'une grande variété de matrices biologiques alternatives, mieux définis ont été utilisés 2-7, leur origine animale ou pauvres évolutivité en fait des candidats inappropriés pour la production industrielle. Par conséquent, l'identification des alternatives synthétiques, à composition définie et des performances fiables, sont des objectifs clés de la recherche sur les cellules souches.

Dans une tentative pour surmonter les limitations des indéfinis substrats de culture de cellules, des collaborations interdisciplinaires entre la chimie et de la biologie ont identifié des matériaux synthétiques ayant la capacité de supporter le phénotype cellulaire. Synthsubstrats étiques sont évolutives, rentables, et peuvent être fabriqués dans des structures 3D complexes, imitant l'environnement in vivo. En raison de ces propriétés des substrats synthétiques ont été largement utilisés pour supporter et entraîner la différenciation de nombreux types de cellules 8-10.

Essais de débit de pointe et haute ont facilité la sélection rapide de matériaux synthétiques, de grandes bibliothèques, et livré de nouveaux matériaux aux propriétés flexibles avec de larges applications dans la recherche et le développement 11-13 biomédicale. Utilisant à haut débit, la technologie de dépistage micro-réseau polymère, nous avons identifié rapidement d'une simple polyuréthane (PU134), adapté pour l'entretien des hépatocytes dérivés de cellules souches humaines. Ce polymère a été jugée supérieure à des substrats provenant des animaux en ce qui concerne la différenciation et la fonction des hépatocytes 14-16. Nous avons par la suite optimisé le processus conditions de revêtement, de la topographie et de stérilisation pour accéder à effetssur le rendement en polymère stabilisant fonction des hépatocytes et la durée de vie. Ceci a des implications importantes en ce qui concerne la compréhension des fondamentaux de la biologie des hépatocytes pour la modélisation à base de cellules et des applications en médecine régénérative.

La technologie décrite ici est un exemple de la façon dont la surface d'un polymère synthétique peut être optimisée pour conserver le phénotype cellulaire. Nous croyons que la combinaison de cette technologie avec un hépatocyte libre protocole de différenciation de sérum efficace a le potentiel de fournir une production évolutive des hépatocytes pour l'utilisation de la modélisation in vitro et la médecine régénérative.

Protocol

1. Synthèse de PHNGAD (poly [1,6-hexanodiol / néopentylglycol / di (éthylène glycol), de l'acide adipique–ALt] diol) Schéma 1: Synthèse de PHNAGD représentation schématique de la synthèse de PHNAGD.. PHNAGD a été préparé par la réaction de 1,6-Hexanodiol, le diéthylène glycol, neoppentyl glycol et d'acide adipique. PHNAGD, Poly [1,6-hexanodiol / …

Representative Results

Polymer solvent influences the topography of the polymer coated surface Polyurethane 134 was solubilized in chloroform, either alone or in combination with toluene or tetrahydrofuran or dichloromethane and the glass slides spin-coated with the different formulations. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to characterize the physical properties of the polymer coatings (Figure 1). The coating obtained using toluene or chl…

Discussion

Many of the current methods used to generate hepatocytes from stem cells rely on undefined matrices of animal origin. These substrates can be costly and highly variable, affecting cell function and stability, representing a significant barrier to application. Therefore, we performed a screen for synthetic materials which support the culture of stem cell derived hepatocytes. We have identified, a simple polyurethane (PU134), formed by polymerizing PHNGAD, MDI and an extender, that in combination with a robust hepatocyte d…

Disclosures

The authors have nothing to disclose.

Acknowledgements

D.C.H., M.B. and F.K. were supported by an EPSRC Follow on Fund. B.L-V and D.S. were each supported by MRC PhD studentships. K.C. was supported by funding from the UK Regenerative Medicine Platform.

Materials

Synthesis, preparation, coating and characterization of polymer PU134 coated coverslips
Shaker Edmun Bühler KS-15
Irradiator CIS Biointernational IBL 637 
Spin coater Specialty Coating System  P-6708
Scanning Electron Microscope  Philips XL30CPSEM
Atomic Force Microscope DimensionV Nanoscope, VEECO
p4-GLO CYP3A4 Promega V8902
UV bulb ESCO
NanoScope analysis software VEECO version 1.20
Fluorescence microscope Olympus TH45200 Use Volocity 4 Software
Tissue culture plates Corning, UK  3527
glass slides Scientific Laboratory Supplies MIC3308
Diethylene glycol Sigma–Aldrich 93171
 1,6-hexanediol Sigma–Aldrich 240117
Neopentyl glycol Sigma–Aldrich 408255
Adipic acid Sigma–Aldrich 9582
anhydrous N,N-Dimethylformamide Sigma–Aldrich 227056
Diethyl ether Sigma–Aldrich 676845
titanium (IV) butoxide  Sigma–Aldrich 244112
1,4-butanediol  Sigma–Aldrich 493732
Vacuum oven Thermoscientific
4,4’-Methylenebis(phenyl isocyanate) Sigma–Aldrich 101688
Tetrahydrofurane Sigma–Aldrich 401757
Sputter coater Bal-Tec SCD 050
Inmunostaining
Phosphate buffer saline (-MgCl2, -CaCl2) Gibco 10010031  Store at room temperature
PBST, PBS made up with 0.1% TWEEN 20    Scientific Laboratory Supplies Ltd EC607 
Methanol   Scientific Laboratory Supplies Ltd CHE5010
Bovine Serum Albumin Sigma-Aldrich, UK A7906
MOWIOL 488 DAPI Calbiochem 475904 Made up in Tris HCL and glycerol as per manufacturers instructions
Cell culture and Functional assay
CYP3A activity pGLO kit Promega V8902
Hepatozyme Gibco 17705021
TryLE express Life Technologies 12604013

References

  1. Zhou, W., et al. SUMOylation of HNF4α regulates protein stability and hepatocyte function. J Cell Sci. 125 (15), 3630-3635 (2012).
  2. Banerjee, A., et al. The influence of hydrogel modulus on the proliferation and differentiation of encapsulated neural stem cells. Biomaterials. 30 (27), 4695-4699 (2009).
  3. Shanbhag, M. S., et al. Neural Progenitor Cells Grown on Hydrogel Surfaces Respond to the Product of the Transgene of Encapsulated Genetically Engineered Fibroblasts. Biomacromolecules. 11 (11), 2936-2943 (2010).
  4. Battista, S., et al. The effect of matrix composition of 3D constructs on embryonic stem cell differentiation. Biomaterials. 26 (31), 6194-6207 (2005).
  5. Tian, W. M., et al. Hyaluronic acid hydrogel as Nogo-66 receptor antibody delivery system for the repairing of injured rat brain: in vitro. Journal of Controlled Release. 102 (1), 13-22 (2005).
  6. Keshaw, H., Forbes, A., Day, R. M. Release of angiogenic growth factors from cells encapsulated in alginate beads with bioactive glass. Biomaterials. 26 (19), 4171-4179 (2005).
  7. Baharvand, H., Hashemi, S. M., Kazemi Ashtiani, S., Farrokhi, A. Differentiation of human embryonic stem cells into hepatocytes in 2D and 3D culture systems in vitro. The International Journal of Developmental Biology. 50 (7), 645-652 (2006).
  8. Cameron, K., Travers, P., Chander, C., Buckland, T., Campion, C., Noble, B. Directed osteogenic differentiation of human mesenchymal stem/precursor cells on silicate substituted calcium phosphate. Journal of Biomedical Materials Research Part A. 101 (1), 13-22 (2013).
  9. Pernagallo, S., Unciti-Broceta, A., Diaz-Mochon, J. J., Bradley, M. Deciphering cellular morphology and biocompatibility using polymer microarrays. Biomedical Materials. 3 (3), 034112 (2008).
  10. Li, Z., Guo, X., Matsushita, S., Guan, J. Differentiation of cardiosphere-derived cells into a mature cardiac lineage using biodegradable poly(N-isopropylacrylamide) hydrogels. Biomaterials. 32 (12), 3220-3232 (2011).
  11. Tare, R. S., Khan, F., Tourniaire, G., Morgan, S. M., Bradley, M., Oreffo, R. O. C. A microarray approach to the identification of polyurethanes for the isolation of human skeletal progenitor cells and augmentation of skeletal cell growth. Biomaterials. 30 (6), 1045-1055 (2009).
  12. Khan, F., Tare, R. S., Kanczler, J. M., Oreffo, R. O. C., Bradley, M. Strategies for cell manipulation and skeletal tissue engineering using high-throughput polymer blend formulation and microarray techniques. Biomaterials. 31 (8), 2216-2228 (2010).
  13. Zhang, R., et al. A thermoresponsive and chemically defined hydrogel for long-term culture of human embryonic stem cells. Nature Communications. 4 (1335), (2013).
  14. Medine, C. N., et al. Developing high-fidelity hepatotoxicity models from pluripotent stem cells. Stem Cells Translational Medicine. 2 (7), 505-509 (2013).
  15. Hay, D. C., et al. Unbiased screening of polymer libraries to define novel substrates for functional hepatocytes with inducible drug metabolism. Stem Cell Research. 6 (2), 92-102 (2011).
  16. Lucendo-Villarin, B., Khan, F., Pernagallo, S., Bradley, M., Iredale, J. P., Hay, D. C. Maintaining hepatic stem cell gene expression on biological and synthetic substrata. BioResearch Open Access. 1 (1), 50-53 (2012).
  17. Hay, D. C., et al. Highly efficient differentiation of hESCs to functional hepatic endoderm requires ActivinA and Wnt3a signaling. Proceedings of the National Academy of Sciences. 105 (34), 12301-12306 (2008).
  18. Szkolnicka, D., Zhou, W., Lucendo-Villarin, B., Hay, D. C. Pluripotent Stem Cell–Derived Hepatocytes: Potential and Challenges in Pharmacology. Annu Rev Pharmecol Toxicol. 53, 147-149 (2013).
  19. Szkolnicka, D., et al. Accurate prediction of drug-induced liver injury using stem cell-derived populations. Stem Cells Translational Medicine. 3 (2), 141-148 (2014).
  20. Medine, C. N., Lucendo-Villarin, B., Zhou, W., West, C. C., Hay, D. C. Robust Generation of Hepatocyte-like Cells from Human Embryonic Stem Cell Populations. Journal of Visualized Experiments. (56), (2011).
  21. Freed, L. E., Vunjak-Novakovic, G. Culture of organized cell communities. Advanced Drug Delivery Reviews. 33 (1-2), 15-30 (1998).
  22. Braam, S. R., et al. Recombinant Vitronectin Is a Functionally Defined Substrate That Supports Human Embryonic Stem Cell Self-Renewal via αVβ5 Integrin. Stem Cells. 26 (9), 2257-2265 (2008).
  23. Rodin, S., et al. Clonal culturing of human embryonic stem cells on laminin-521/E-cadherin matrix in defined and xeno-free environment. Nature Communications. 5 (3195), (2014).
  24. Thaburet, J. -. F. O., Mizomoto, H., Bradley, M. High-Throughput Evaluation of the Wettability of Polymer Libraries. Macromolecular Rapid Communication. 25 (1), 336-370 (2003).
  25. Lim, J. Y., Donahue, H. J. Cell Sensing and Response to Micro- and Nanostructured Surfaces Produced by Chemical and Topographic Patterning. Tissue Engineering. 13 (8), 1879-1891 (2007).
  26. Teixeira, A. I., Abrams, G. A., Bertics, P. J., Murphy, C. J., Nealey, P. F. Epithelial contact guidance on well-defined micro- and nanostructured substrates. Journal of Cell Science. 116 (10), 1881-1892 (2003).
  27. Biggs, M. J. P., Richards, R. G., Wilkinson, C. D. W., Dalby, M. J. Focal adhesion interactions with topographical structures: a novel method for immuno-SEM labelling of focal adhesions in S-phase cells. Journal of Microscopy. 231 (1), 28-37 (2008).
  28. Karuri, N. W., Porri, T. J., Albrecht, R. M., Murphy, C. J., Nealey, P. F. Nano- and microscale holes modulate cell-substrate adhesion, cytoskeletal organization, and -beta1 integrin localization in SV40 human corneal epithelial cells. IEEE Transactions on Nanobioscience. 5 (4), 273-280 (2006).
  29. Hamilton, D. W., Brunette, D. M. The effect of substratum topography on osteoblast adhesion mediated signal transduction and phosphorylation. Biomaterials. 28 (1), 1806-1819 (2007).
  30. Engler, A. J., Sen, S., Sweeney, H. L., Discher, D. E. Matrix elasticity directs stem cell lineage specification. Cell. 126 (4), 677-689 (2006).
  31. Dang, J. M., Leong, K. W. Myogenic Induction of Aligned Mesenchymal Stem Cell Sheets by Culture on Thermally Responsive Electrospun Nanofibers. Advanced Materials. 19 (19), 2775-2779 (2007).
  32. Azevedo, E. C., Nascimento, E. M., Chierice, G. O. UV and gamma irradiation effects on surface properties of polyurethane derivate from castor oil. Polímeros. 23 (3), 305-311 (2013).
  33. Rosu, L., Cascaval, C. N., Ciobanu, C., Rosu, D. Effect of UV radiation on the semi-interpenetrating polymer networks based on polyurethane and epoxy maleate of bisphenol A. Journal of Photochemistry and Photobilogy A: Chemistry. 169 (2), 177-185 (2005).
  34. Yang, X. F., Tallman, D. E., Bierwagen, G. P., Croll, S. G. Blistering and degradation of polyurethane coatings under different accelerated weathering tests. Polymer Degradation and Stability. 77 (1), 103-109 (2002).

Play Video

Cite This Article
Lucendo-Villarin, B., Cameron, K., Szkolnicka, D., Travers, P., Khan, F., Walton, J. G., Iredale, J., Bradley, M., Hay, D. C. Stabilizing Hepatocellular Phenotype Using Optimized Synthetic Surfaces. J. Vis. Exp. (91), e51723, doi:10.3791/51723 (2014).

View Video