Recreating stem-cell niches using self-assembling biomaterials

Stem-cell niche constitutes a dynamic and complex extracellular environment around stem cells, providing signals for self-renewal and differentiation. Existence of separate niches for different types of stem cells, varying in their composition and properties, implies the requirement for unique combination of niche-specific signals. With the growing interest on artificial stem-cell niche for application in tissue engineering and regenerative medicine, a major challenge is to incorporate these signals in a synthetic and defined material environment. Self-assembling biomaterials are built on the principles of noncovalent interactions with their modular design offering unprecedented control over presentation of structural and biochemical cues. This review will cover the general strategies for incorporating niche extracellular matrix (ECM) signals in biomaterial scaffold and the unique advantages gained from exploiting the principles of molecular self-assembly. Our focus will be restricted to self-assembling peptide and proteins, two major categories of materials in this class. Use of these materials on various stem-cell applications and some of the future challenges and opportunities will be discussed.