A Review on Extracellular Matrix Mimicking Strategies for an Artificial Stem Cell Niche

In adults, stem cells live in a distinctive microenvironment known as "stem cell niche". Within such a niche, biochemical and biophysical attributes of extracellular matrix (ECM) executes a major role in regulating stem cell self-renewal and differentiation. However, in conventional in vitro culture system, stem cells are deprived of ECM and hence it is difficult to maintain, expand and differentiate them into a particular lineage. Therefore, different two- and three-dimensional substrates have been designed to mimic the ECM features in vitro. The present review focuses mainly on different scaffolds/substrates made up of or functionalized with proteins, polysaccharides and peptides (biochemical) in form of fibers, gels, gratings, pillars, pits (geometrical) of varying stiffness, and mechanical pressure (mechanical) for replicating stem cell microenvironment that not only helps in understanding stem cell-ECM interactions but also in the development of systems for regenerative medicine applications.