Designing ordered micropatterned hydroxyapatite bioceramics to promote the growth and osteogenic differentiation of bone marrow stromal cells.

Patterned structured surfaces are very useful to control a cell's microenvironment and to modulate certain cellular responses, such as cell adhesion, migration, proliferation, and differentiation. Herein, ordered micropatterns constructed by a quadrate convex with different sizes were fabricated on a hydroxyapatite [Ca10(PO4)6(OH)2, HAp] bioceramic surface using an ordered micropatterned nylon sieve as templates. The height, width and space of the convex for the patterns could be facilely regulated via simply tailoring the meshes of the template. Compared with traditional samples with flat surfaces, the fabricated HAp bioceramics with micropatterned surfaces possessed better wettability and higher surface energy, which significantly promoted the adhesion, proliferation, and osteogenic differentiation of rat bone marrow stromal cells (bMSCs). Furthermore, using a pattern size close to that of the cell size showed a better stimulation of cell response compared with larger pattern sizes. Our study suggests that the fabrication of micropatterned structured HAp bioceramics is critical for designing optimal biomaterials for bone regeneration and cell culture substrate applications.