Histological analyses of 3 week old Col27delskel tibial growth plates.
The organisation of proliferative zone chondrocytes in MΔskel /MΔskel mice (B) were highly disorganised and cells lacked the translucent pericellular matrix apparent in the phenotypically normal (+/MΔskel) littermates (A). Collagen XXVII immunostaining in control (C) and MΔskel /MΔskel (D) growth plates were of similar intensity but MΔskel /MΔskel lacked the stain-free pericellular zone apparent in controls. Expression of type II collagen in mice homozygous for the Col27delskel allele (F) appeared normal when compared to the control littermates (E). Collagen X immunostain was limited to the hypertrophic zone in controls (G) but appeared to extend into lower part of the proliferative zone in MΔskel /MΔskel mutant growth plates (H). Free hyaluronan was localized to the pericellular matrix in controls (I) but was more diffusely distributed in MΔskel /MΔskel growth plates (J). BrdU labeling of proliferative zone chondrocytes in control (K) and MΔskel /MΔskel growth plates (L). The disorganization and failure of the cells to from efficiently form columns is apparent in the mutant growth plate (L).