Motivation for noninvasive optical imaging of stem cells in vitro: adhesion phenotyping of stem cell differentiation

Material-based approaches to regulate stem cell fate decisions in vitro

Stem cell function is carefully orchestrated by an array of intrinsic and extrinsic factors [1-3]. A large number of cellular, biophysical, and chemical cues have been found to directly and indirectly impact stem cell fate decisions at different stages during development, at homeostasis, and following injuries [3]. These findings present opportunities to design and develop material-based approaches to allow better understanding of the underlying mechanisms of stem cell regulation as well as the realization of currently unmet clinical and therapeutic needs [3-5]. Combined with advances in fabrication approaches, sophisticated constructions of micro- and nanoscale features with varying material properties are now possible to selectively decouple or integrate experimental parameters that maximize the intended outcome of bioengineering applications [2,3,5].

Material-based approaches using stem cells often take advantage of the material properties to regulate stem cell function or fate decisions [4,6]. It has been reported that bulk material properties (e.g., pore size, pore alignment, stiffness, permeability) as well as surface properties (e.g., chemistry, topography, surface-bound ligand presentation, and orientation) at the cell-material interface serve as important regulators of stem cell fate: quiescence, self-renewal, differentiation, mobilization, homing, and senescence for several types of stem cells, such as mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), hematopoietic stem cells (HSCs), and neuron stem cells (NSCs) [2,3].