Figure 4.

Histological Safranin-O staining of cartilage ECM (extracellular matrix). Control and actively treated cartilage samples for (A) articular (deep zone), (B) auricular, (C) meniscal, and (D) nasal cartilage indicating presence of sulfated glycosaminoglycan (sGAG; pink/red). Row (i, ii) native control, (iii, iv) chondroitinase ABC active, (v, vi) guanidine hydrochloride active, and (vii, viii) hyaluronidase active. Black arrow heads indicate alignment of sGAG with collagen content in meniscal cartilage.