An experimental investigation of the effect of mechanical and biochemical stimuli on cell migration within a decellularized vascular construct.

The goal of this study was to promote rapid repopulation of the medial layer of decellularized tissues for use as vascular grafts. We utilized a combined approach of biochemical and mechanical stimuli to enhance repopulation of decellularized porcine arterial tissue. Chitosan β-glycerophosphate loaded with hepatocyte growth factor (HGF) was injected into a channel in the artery wall while rat mesenchymal stem cells (rMSCs) were injected in two channels located 120° to this channel. In a second group rMSCs were injected into channels located at intervals of 120°. Both groups were subjected to 7 days mechanical stimuli in comparison to non-dynamically conditioned static controls. The combined effect of the biochemical and mechanical stimuli demonstrated that the repopulation zone was significantly enhanced, maximum migration achieved was 1.8 times more than that of the static HGF cultured control and 10 times higher than the average migration for statically cultured scaffolds without biochemical stimulus. Human umbilical vein endothelial cells were also successfully adhered to the scaffold and dynamically cultured. The response of medially injected cells to the biomechanically and biochemically altered environment demonstrated that enhanced circumferential scaffold repopulation could be achieved.