Aims: It is well known that the success of an orthopedic implant is determined by a close apposition between bone and implant surface. The excellent physical properties and the controlled degradation of poly-ε-caprolactone (PCL) has been shown, however the suitability for bone engineering applications of a material is critically influenced by the interactions between cells and scaffold. The aim of this study was to evaluate the interaction between bone marrow cells and PCL surface. Bone marrow cells were obtained from femurs of New Zealand rabbits and seeded on PCL directly (WBMC) or after gradient centrifugation (MSC), mimicking the in vivo colonization of PCL after implantation and the pre-seeding strategy.

Methods: PCL was dissolved in chloroform (3% w/v solution) and spin coated as a thin (100nm) film onto p-doped silicon wafers. The surface wettability and roughness were analyzed by SFE measurements and AFM. Cells were seeded on PCL and adhesion/proliferation evaluated at 1, 7, 14, 21 and 28 days. Fluorescence microscopy and SEM imaging were performed at defined time endpoints.

Results: At 2 wks adherence-selected MSC had already formed confluent multilayers, whereas WBMC were still semi-confluent. At 4 wks a consistent layer of ECM was observed underneath the cell layers of both cultures.

Conclusions: PCL is a proper substrate for bone cell attachment and growth, as cell confluence was reached at 2 wks for MSC and at 3–4 wks for WBMC. To avoid any risk of bacterial contamination, the seeding of WBMC on PCL scaffold, which implies reduced handling of cells outside the body, was shown to be effective and may be recommended in the clinical practice.