Fluorescence imaging of multiple myeloma cells in a clinically relevant SCID/NOD in vivo model: biologic and clinical implications. Cancer Res

The in vivo preclinical testing of investigational therapies for multiple myeloma (MM) is hampered by the fact that models generated to reca-pitulate the development of diffuse skeletal lesions after i.v. injections of tumor cells do not allow for ready detection of the exact site(s) of lesions or for comprehensive monitoring of their progression. We therefore de-veloped an in vivo MM model in severe combined immunodeficient/ nonobese diabetic mice in which diffuse MM lesions developed after tail vein i.v. injection of human RPMI-8226/S MM cells stably transfected with a construct for green fluorescent protein (GFP). Using whole-body real-time fluorescence imaging to detect autofluorescent GFP MM cells (and confirming the sensitivity and specificity of these findings both histologically and by flow cytometric detection of GFP cells), we serially monitored, in a cohort of 75 mice, the development and progression of MM tumors. Their anatomical distribution and pathophysiological man