Fig. 5. Osteocyte process formation in cortical bone is dependent on MT1-MMP. Cortical bone sections stained with Bodian silver stain (A,B) or Giemsa stain (C,D). (A) Bone from 30-day-old MT1-MMP-deficient mouse displaying the absence of clearly defined osteocyte processes. The conspicuous mesh-like appearance of the bone matrix seen in wild-type mice is absent from this sample (Fig. 1). (B) Bone from a 40-day-old MT1-MMP-deficient mouse displaying a similar absence of osteocyte processes despite more advanced age. (C,D) Osteocyte processes are absent from these Giemsa-stained bones from a 20-day-old (C) and a 40-day-old (D) MT1-MMP-deficient mouse. Bars, 10 µm (A-C).