FIG. 5.

Histological differences between hNAC, hMSC-derived 3D cartilage, and human adult diseased AC. Paraffin-embedded sections were stained with toluidine blue and safranin O to assess relative glycosaminoglycan/proteoglycan content in samples. A more homogeneous distribution of cartilage extracellular matrix is observed in hNAC compared to hMSC-derived 3D cartilage and adult cartilage. For immunohistochemistry, sections were incubated with anti-mouse Ig (ImmPRESS™ polymerized reporter enzyme staining). High expression of collagen type 2 is observed in hNAC compare to the other cartilage tissues. Expression of matrilin-1 and unique cartilage matrix-associated proteins was detected in hNAC and not in hMSC-derived 3D cartilage, which correlated with the microarray data. Some small degree of expression was found in adult diseased cartilage. Color images available online at www.liebertpub.com/tea