FIG. 4.

The GAG mimetic [OTR₄₁₂₀] immobilized on the TCP/HA substitutes inhibits bone formation induced by hMSC in the ectopic site. Controls and/or functionalized and/or cellularized scaffolds were implanted on mice and harvested after 8 weeks for histological study. (A) Masson's trichrome stain revealed the collagenic fibrillar tissue (arrow). (B) ALP activity staining showed violet areas with osteoblastic precursor cells (stars). (C) Toluidine blue staining indicated the host inflammatory response (arrow). (D) Tartrate-resistant acid phosphatase (TRAP) staining highlighted the red foci of osteoclastic cells (stars). Bn, bone nodule; Sc, scaffold; Bo: border. Scale bar: 200 μm. Pictures are representative of n=12 samples (2 substitutes per mice×2 mice×3 independent experiments). Semiquantitative analysis of this histological study was reported in Table 1. Color images available online at www.liebertpub.com/tea