Static and dynamic cell culture of small caliber bilayer vascular grafts electrospun from polycaprolactone

Developing a suitable vascular graft to replace damaged small-caliber vessels and promote tissue regeneration is a critical challenge. This study focuses on bilayer polycaprolactone (PCL) grafts, fabricated by electrospinning, with both randomly distributed and radially oriented fibers. The analysis covers surface morphology, fiber diameter, pore size, cellular behavior, and biodegradability. Human umbilical vein endothelial cells (HUVECs) show an impressive viability of 142.2% after 7 days, while umbilical artery smooth muscle cells (UASMCs) exhibit 112.6%. Fluorescent microscopy indicates a higher viability of HUVECs over UASMCs. On the other hand, less than 10% of HUVECs and less than 5% of UASMCs undergo cell death within 7 days. Biodegradation analysis over 12 months shows a significant weight loss of 65-70% for both types of fiber arrangements. A custom-designed bioreactor enables dynamic cell culture, revealing comparable activity to static cultures. In the dynamic cell culture environment, HUVECs maintain high viability and display robust proliferation at both the 4th and 7th days, supporting the results observed in static cell cultures. These findings underscore the significant potential of bilayer PCL grafts in advancing the field of blood vessels, offering promising avenues for the development of functional vascular replacements with enhanced regenerative capabilities.