Natural and Synthetic Materials for Self‐Renewal, Long‐Term Maintenance, and Differentiation of Induced Pluripotent Stem Cells

Abstract

Induced pluripotent stem cells (iPSCs) have attracted considerable attention from the public, clinicians, and scientists since their discovery in 2006, and raised huge expectations for regenerative medicine. One of the distinctive features of iPSCs is their propensity to differentiate into the cells of three germ lines in vitro and in vivo. The human iPSCs can be used to study the mechanisms underlying a disease and to monitor the disease progression, for testing drugs in vitro, and for cell therapy, avoiding many ethical and immunologic concerns. This technology offers the potential to take an individual approach to each patient and allows a more accurate diagnosis and specific treatment. However, there are several obstacles that impede the use of iPSCs. The derivation of fully reprogrammed iPSCs is expensive, time-consuming, and demands meticulous attention to many details. The use of biomaterials could increase the efficacy and safety while decreasing the cost of tissue engineering. The choice of a substrate utilized for iPSC culture is also important because cell-substrate contacts influence cellular behavior such as self-renewal, expansion, and differentiation. This Progress Report aims to summarize the advantages and drawbacks of natural and synthetic biomaterials, and to evaluate their role for maintenance and differentiation of iPSCs.

Engineering Hydrogel Microenvironments to Recapitulate the Stem Cell Niche

“…In 2010, three separate research groups identified fully defined engineered matrix compositions that permitted feeder-free expansion of ESCs: recombinant laminin 511 (100), acrylate surfaces presenting RGD peptides (101), and synthetic poly[2-(methacryloyloxy)ethyl dimethyl-(3-sulfopropyl)ammonium hydroxide] (PMEDSAH) grafted surfaces (102). Since these reports, various other naturally derived and synthetic materials have been developed to support the culture of undifferentiated PSCs (103). In addition to controlling surface biochemistry, biophysical interactions with the substrate must also be considered.…”

Cartilage Tissue Engineering by the 3D Bioprinting of iPS Cells in a Nanocellulose/Alginate Bioink

“…These hydrogels have been shown to encapsulate iPSCs well enough for injecting into structures with desired architectures, sustaining stem cell pluripotency, and supporting differentiation in 3D 16 . These biomaterials were all found to support spatial distribution and to promote the expansion and maturation of iPSC populations in long-term cultures for up to 3–4 months 17–19 . In addition, combinations of these materials have viscoelastic properties that allow rapid prototyping via the inkjet printing of defined architectural constructs 16, 20 .…”

Controlled drug release for tissue engineering

“…Porous scaffolds and hydrogels are also amenable to the development of patient-specific regenerative treatment sutilizing the potential of induced pluri potent stem cells (iPSCs). 122 Advances on all three fronts of tissue engineering – material matrix design, drug delivery, and regenerative cells – will help to push the field into clinical use in the near future.…”