Fig. 3.

Untreated, injured dog menisci showed lubricin infiltration on the torn surface (arrow) (A). Treatment with 1 M NaCl for an hour depleted lubricin on the meniscus surface (B) that led to improvement in healing by 4 weeks (C). Nanoindentation-mediated modulus mapping, showing indentation moduli in 220 μm × 120 μm area at 20 μm intervals (D) revealed a modest improvement in healing of NaCl pre-treated explants. Effective modulus (E_Eff) from the nanoindentation measurements also showed significant increase in NaCl pre-treated group (E) (*:p < 0.001; n = 25 per group), suggesting an improved functional recovery. Then lubricin coating was established on meniscus explants by incubating with synovial fluids (SF) up to 24 h, resulting in robust lubricin coating on cut surface of bovine menisci as compared to negative controls (no coating and no antibody) (F & G). The lubricin coating for 24 h at 37 °C led to impaired tissue integration and healing both with fibrin and FibGen, delivered with CTGF and TGFβ3-μS (PR staining) (H) (images are from two magnification per group; all samples were lubricin pre-coated).