Effect of pore size on cell adhesion in calcium phosphate cement scaffolds

Abstract

Objective To study the effect of different pore sizes of calcium phosphate cement (CPC) scaffolds on cell adhesion. Methods Rat bone mesenchymal stem cells (BMSCs) primarily cultured were used in the present study. CPC scaffolds of 3 pore sizes (200 to 300 (μm, 300 to 450 μm, 450 to 600 μm) were respectively groups A, B and C. Micro-CT was used to analyze the average pore size and porosity of each group. The 3 kinds of CPC were placed in 24-well plates and 2 × 105 cells were incubated per well. In each group, the cells were harvested 12 and 24 hours after incubation to count cell numbers and adhesion rate. Cell apoptosis and necrosis were detected by flow cytometry and cell morphology and adhesion were observed by scanning electron microscope (SEM) 24 hours after incubation. Results Micro-CT showed that pores of the CPC used in this study were interconnected and the porosity of each group was greater than 67%. The average pore sizes of the 3 groups were 240 μm, 410 μm and 510 μm respectively. At 12 hours, there were no significant differences between the 3 groups in cell adhesion and necrosis ( P > 0. 05). At 24 hours, cell adhesion in group A was significantly less than in groups B and C ( P < 0. 05), and cell necrosis in group A was significantly more than in group C (P < 0. 05). Conclusion In CPC scaffolds for culture of BMSCs,cell adhesion rate may increase gradually and cell necrosis may decrease gradually with the increase of pore size. Key words: Calcium phosphate cement;  Bone marrow;  Mesenchymal stem cells;  Cell adhesion;  Rats