Cells morphology on the composite scaffolds (HA: PCL = 1:1). Panel (A) showed osteoblasts proliferating on PCL-HA scaffolds (400×). Panel (B) was an enlargement of Panel (A) showing the details of the attached osteoblasts with meshwork of extracellular matrix (arrows), and cellular projection (1500×). Panels (C) and (D) revealed the growth of endothelial cells on a PCL-HA scaffold. The Panel (C) pictured ECs proliferating and forming a cell sheet (600×), and Panel (D) magnified attached ECs to detail their cobblestone shape and cellular extensions (4000×).