Our group was the first to describe the presence of putative smooth muscle progenitor cells in the circulation of humans. Around this time we also published the first definitive evidence of human bone marrow derived smooth muscle precursors participating in atherosclerotic plaque biology. Together these findings prompted in our lab a fundamental re-evaluation of the contribution of circulating cells to smooth muscle biology in vascular disease.
In collaboration with transplant surgery colleagues at Mayo Clinic we showed that recipient cells contribute significantly to intimal smooth muscle in the plaque of transplant vasculopathy. Moreover our finding that~10% of plaque smooth muscle cells are bone marrow derived within 4 years of transplant suggest an active and functionally significant biology that can be exploited to gain new insights into the genesis of atherosclerosis.
For instance we have recently used smooth muscle progenitor cells as a cellular assay for predicting the therapeutic efficacy of a number of vascular cytostatic and cytotoxic drugs used on drug eluting stents. We have been able to use these cells as a means of rapidly screening drugs used by the device industry with good predictive success. This assay is currently under patent development and will ultimately be licensed to industry to aid rapid screening of drugs suitable for vascular device interfacing. Moreover we have developed real-time arterial flow assays of in situ adhesion and rolling of putative progenitor cells to activated endothelium and candidate vascular adhesion molecules. This has provided a fertile field for small molecule discovery.