UCLA

Background: Pericytes are abluminal mural cells implicated in angiogenesis, remodeling, stabilization, and maturation of microvasculature in the brain, lungs, kidneys, and retina. These cells have been reported to dissociate from the surrounding microvasculature following an ischemic injury. However, little information is known about cardiac pericyte migration and proliferation following a myocardial infarction (MI).

Methods: CSPG4CreERT2/+;Rosa26 Ai9tdT/+ mice were used to measure pericyte migration and proliferation following a MI time course. CSPG4CreERT2/+;p53flox/flox mice were used to measure the impacts of knocking out p53 within pericytes under healthy and MI conditions.

Results: Cardiac pericytes increase in size starting at 7-days post-injury and undergo peak proliferation at 14-days post-injury. Cardiac pericytes reached peak migration at distances >45�m 7-days post-injury. No phenotypic differences were observed between p53 KO and WT pericytes at baseline.

Conclusions: Increases in pericyte proliferation and migration at later time points could indicate that pericytes contribute to the pro-reparative response in the heart after MI.