CXCL12 and myocardial infarction: This can be counteracted by modifying the structure of SDF-1, which makes the chemokine less susceptible to the action of proteolytic enzymes (S4V) [33], or the sustained release of a biocompatible carrier (fibrin-polyethylene glycol carriers) that releases SDF-1 for 28 days (mouse model of myocardial infarction) [34].