A novel automated cell-seeding device for tissue engineering of tubular scaffolds: design and functional validation

Obtaining an efficient, uniform and reproducible cell seeding of porous tubular scaffolds constitutes a major challenge for the successful development of tissue-engineered vascular grafts. In this study, a novel automated cell-seeding device utilizing direct cell deposition, patterning techniques and scaffold rotation was designed to improve the cell viability, uniformity and seeding efficiency of tubular constructs. Quantification methods and imaging techniques were used to evaluate these parameters on the luminal and abluminal sides of fibrous polymer scaffolds. With the automated seeding method, a high cell-seeding efficiency (~89%), viability (~85%) and uniformity (~85-92%) were achieved for both aortic smooth muscle cells (AoSMCs) and aortic endothelial cells (AoECs). The duration of the seeding process was < 8 min. Initial cell density, cell suspension in matrix-containing media, duration of seeding process and scaffold rotation were found to affect the seeding efficiency. After few days of culture, a uniform longitudinal and circumferential cell distribution was achieved without affecting cell viability. Both cell types were viable and spread along the fibres after 28 h and 6 days of static incubation. This new automated cell-seeding method for tubular scaffolds is efficient, reliable and meets all the requirements for clinical applicability.