Application of a rotating bioreactor consisting of low-cost and ready-to-use medical disposables for in vitro evaluation of the endothelialization efficiency of small-caliber vascular prostheses.

The incomplete endothelialization of especially small-caliber vascular prostheses after implantation in patients is a major disadvantage in cardiovascular interventions. The lack of an endothelium leads to the occurrence of thrombosis at the luminal surface of artificial vascular prostheses. Thus, the development of new graft materials and coatings for induction of complete endothelialization on the implant surfaces is a promising approach to improve hemocompatibility and maintain long-term graft patency. In this study, we designed a rotation model to evaluate the early endothelial cell (EC) seeding efficiency of different small-caliber vascular devices, such as stents and vascular grafts. The suitability of the designed rotation model for endothelialization studies was investigated by seeding and cultivation of prostheses with ECs followed by scanning electron microscopy. Furthermore, the viability of attached ECs was determined by calcein acetoxymethyl ester (AM) staining. The rotation model consisting of low-cost medical disposables enabled sterile incubation and cultivation of ECs with vascular devices. Simultaneously, the rotation of the bioreactor ensured a uniform distribution and adhesion of cells to the devices. Calcein AM staining of adherent cells on prostheses revealed excellent cell viability. Moreover, using the designed rotation model, an influence of different coatings and materials on the adhesion and spreading of ECs was demonstrated. The rotating bioreactor described and used in this study not only saves time and money but is also eminently useful for the accelerated preclinical evaluation of the endothelialization efficiency of different materials and surface coatings of small-caliber vascular devices.