The authors make gelatin-PEG tyramine gels (GPT gels) that they
functionalize with a SVVYGLR peptide. The SVVYGLR sequence, often found
near an RGD sequence in different types of ECM, has been shown to
improve adhesion, migration, and tube formation of endothelial cells.
Crosslinking and bioconjugation of the peptide sequence is done using a
horseradish-peroxide (HRP) mediated tyrosine radical dimerization. The
authors then demonstrate that human umbilical endothelial cells have
better attachment and proliferation on gels containing the SVVYGLR
sequence than on gels containing just RGD. They also look at the
vascularization of gels subcutaneously injected into rats.
Most interesting aspects of the paper are the enzyme-mediated cross-linking and the SVVYGLR peptide.