Reversal of osteopetrotic phenotype in oc/oc+tcirg1 mice as demonstrated by X-ray and histology. The left column (A-D) shows X-ray images and the right column (E-H) shows the corresponding histology images (femur). Three-week-old untreated control mouse (A,E), a 3-week-old untreated oc/oc mouse (B,F), 8-week-old oc/oc+tcirg1 mouse (C,G), and 18-week-old oc/oc+tcirg1 mouse (D,H). Note that bone marrow volume increases at the expense of bone volume in oc/oc+tcirg1 compared to untreated oc/oc mouse. Olympus BX45 microscope, (PLAN 4× magnification, 0.1 aperture for [E], [F], and [H]; 1.25× magnification and 0.04 aperture for [G]) and Nikon Prixera PRO 150 ES were used for the histology images.