The native extracellular matrix (ECM) is a complex and heterogeneous
material containing numerous multifunctional proteins
that provide cells with structural support and biochemical signals
to facilitate a series of important cellular processes [1]. First, the
ECM presents integrin-specific ligands and binding affinity to other
cell-surface receptors that combine to initiate cell adhesion. Second,
through complex and dynamic interactions with cells, the matrix
provides a three-dimensional (3D) mechanical framework.
These biochemical and biomechanical cues activate highly regulated
signaling pathways that allow for ensuing cellular responses
such as spreading, migration, proliferation, and differentiation.
In order to mimic these important functions of native ECM in
the design of biomaterial scaffolds, the strategy of using isolated
ECM components (collagen, fibronectin, etc.) or their mixtures harvested
from tissues has been widely adopted [2]. Although often
highly cell adhesive, these biomaterial scaffolds have proved