A collagen/vascular smooth muscle cells (SMCs) incorporating elastic scaffold for tissue-engineered vascular graft

Statement of Purpose: This study was focused on a collagen/cell mixture seeding method to improve the adhesion and proliferation of vascular smooth muscle cells (SMCs) in tubular porous scaffolds for vascular grafts application. Recently, poly(L-lactide-co-εcaprolactone) (PLCL) copolymers have been applied as a biomaterial for vascular graft due to the high elastic property. We previously reported that tubular PLCL scaffolds were fabricated as a mechanically active artificial blood vessel by an extrusion-particulate leaching technique. However, these extruded PLCL scaffolds caused a few problems to be improved in respect of not only the cell seeding efficiency and cell in-growth. In this study, we sought to introduce a hydrogel seeding method for the enhancement of SMCs seeding and proliferation into tubular PLCL scaffolds. Methods: Tubular porous scaffolds (ID: 4 mm, OD: 6 mm) were fabricated from a biodegradable elastic polymer, poly(L-lactide-co-ε-caprolactone) (PLCL) (50:50, Mn 1.58 × 10), by an extrusion/particulate leaching method (pore size : 50~100 μm, 100~200 μm, and 300~500 μm). SMCs incorporating collagen solution was infiltrated in PLCL scaffolds under vacuum and incubated for 1 h at 37 C to form collagenous gel. The optimal condition of the seeding process was determined by investigating cell viability and cell adhesion rate depending on pressure and gelation time. Cell adhesion and cell viability were determined by Water-soluble Tetrazolium salts (WST) assay and Lactate dehydrogenase (LDH) assay, respectively.