Micro-CT and quantitative analysis of tibia and spine following hMSC-OPG therapy. Four weeks after tumor challenge, a time established as midpoint for the degree of osteolytic damage, cohorts of mice from untreated and indicated treatment groups were euthanized, and tibia (A) and spine (B) were subjected to micro-CT analysis. Data obtained from micro-CT were used in 3D reconstruction images and quantitative analysis of respective bones for connectivity density, trabecular number, and trabecular spacing (*P < .05; **P < .01, compared with untreated mice following tumor challenge).