Figure 6.

Identification of bone ECM related protein in OI-iPSC constructs cultured for 35 days in Elp500. Histological analysis was performed using HE, methylene blue-counterstained von Kossa, and Movat's pentachrome staining (without decalcification of sections). (a–c) Representative images of OI-iPSC constructs stained with (a) HE, (b) methylene blue-counterstained von Kossa, and (c) Movat's pentachrome. The right panels show magnifications of the dashed square regions. Black arrows indicate the outer cell layer. The inner cell layer is located in between the dashed line and dotted line. The inner ECM is indicated by asterisks. (d and e) Immunofluorescent assessment of (d) type I collagen and (e) osteocalcin in OI-iPSC constructs. The white dotted line separates OI-iPSC constructs into two layers; the outer layer is indicated by triangles and the inner layer is indicated by asterisks. Positive staining of cells for type I collagen and osteocalcin is demonstrated using white arrows. Scale bars: 50 μm.