Basel Sharaf, Caroline B. Faris, Harutsugi Abukawa, Srinivas M. Susarla, Joseph P. Vacanti, Leonard B. Kaban, Maria J. Troulis
The purpose of this study was to evaluate porcine bone marrow–derived progenitor cell (pBMPC) proliferation and penetration into a novel 3-dimensionally printed scaffold. Four different tissue engineering scaffolds to evaluate pBMPC proliferation and penetration were examined. Scaffolds were fabricated from polycaprolactone (PCL) or the combination of β-tricalcium phosphate (β-TCP) and PCL (50:50), with 2 separate channel sizes (1 mm [small (S)] vs 2 mm [large (L)]). Scaffolds were fabricated into 20 × 20 × 7–mm blocks by use of a TheriForm machine (Integra Life Sciences, Akron, OH). Four groups of scaffolds were examined for pBMPC proliferation and penetration: group 1, β-TCP/PCL S; group 2, β-TCP/PCL L; group 3, PCL S; and group 4, PCL L. Nonparametric mean (Kruskal-Wallis) and multiple comparisons tests were used to compare the 4 groups. No shrinkage or deformation was noted in any of the scaffold groups after 2 weeks of culture. Mean surface cell counts ranged from 13.4 to 87.8 cells/0.57 mm2, with group 1 (β-TCP/PCL S) having statistically significantly higher counts than the other groups (P < .001). Mean interior cell counts ranged from 10.9 to 75.6 cells/0.57 mm2, with group 1 having the greatest interior cell count (P < .001). Total collagen formation ranged from 0.2% to 86%, with group 1 having the highest collagen formation (P < .001). The 3-dimensionally printed scaffold (β-TCP/PCL) with 1-mm channels showed greater cellular proliferation, penetration, and collagen formation after a 2-week in vitro culture than the other scaffolds evaluated. β-TCP/PCL S scaffolds warrant further evaluation for bone tissue engineering in vivo.