Recapitulating vascular formation: beyond the ECM
To create a cellular microenvironment for vascular development, the
hydrogel scaffold should provide cell adhesion domains to control
vascular cell behavior. The cell-adhesion moieties are incorporated
intomatrices during hydrogel formation and allowcell attachment and
vascular morphogenesis through cell-matrix interaction. The RGD
peptides have been widely used as a cell adhesion domain, as integrinmediated
cell adhesion plays a key role in vascular development, for
example in EC attachment, migration, differentiation and vascular
morphogenesis (Hanjaya-Putra et al., 2011; Le Saux et al., 2011). In
addition,MMP-sensitive degradable sites,which allowcleaving of the
biomacromolecular components of the ECMs, should be included, as
ECM remodeling is an important aspect of vascular morphogenesis
and tube formation, aswell as chemotacticmigration and proliferation
of ECs (Stratman et al., 2009). These signaling domains are key
parameters in the design of emerging hydrogel materials in vascular
engineering.