Bioluminescence imaging of G1-HRD-luc mouse. (A) G1-HRD-luc expression under steady state conditions. The relative light intensity emitted from the mouse was quantified by imaging analysis software according to the color scale (photons per second) shown on the right. Bioluminescent images (top panels) and their corresponding black-and-white photographs (bottom panels) of the lateral (left), dorsal (middle), and ventral (right) views are shown. Spl indicates spleen; F, femur; Spi, spine; St, sternum; T, testis. (B) Ex vivo bioluminescent images of isolated bone marrow (left) and spleen (right) from G1-HRD-luc mice. For the imaging of bone marrow, both ends of the 2 femoral bones were cut and put into luciferin. Bioluminescent image (top panel) and its corresponding black-and-white photograph (bottom panel) are shown.