Figure 5.

Decreased in vitro differentiation and maturation of primary temporomandibular joint chondrocyte cultures from Ddr2^slie/slie mice. Primary temporomandibular joint condyle chondrocytes were isolated from 3-mo-old wild-type (WT) and homozygous Ddr2^slie/slie mice (DDR2) and grown in chondrogenesis medium for up to 15 d. Five-day cultures were used for alcian blue staining (A) and immunohistochemistry for collagen X (B). Fifteen-day cultures were stained for mineral with alizarin red (C). Cultures from day 0 to day 15 were used for reverse transcription quantitative real-time polymerase chain reaction detection of temporal changes in chondrocyte gene expression: (D) Col2a1 (Col 2), (E) cartilage oligomeric matrix protein (Comp), (F) Col10a1 (Col X), (G) matrix metalloproteinase 13 (MMP13), (H) runt-related transcription factor 2 (Runx2), and (I) bone gamma carboxyglutamate protein 2 (Bglap 2). Values were normalized to Gapdh mRNA. Scale bar: 40 µm for panels A–C.