Quantification of BLI signal was performed as previously described
52 (link). The
Living Image software 4.4 (Caliper Life Sciences, Mainz, Germany) was used for data acquisition and quantification of light emission using a scale with a minimum of 1.8×10
4 photons per second per cm2 per solid angle of one steradian (sr). Different regions of interest (ROI) were defined and signals were considered positive, when light emission exceeded background in each ROI. Background was measured in mice harboring GLuc negative leukemias. A ROI covering the entire animal was used (background 4×10
6 photons per second). As an exception to determine early engraftment, a small ROI covering the femurs was used (background 6×10
4 photons per second), as light emission became visible there first. Overt leukemia was considered above 10
10 photons per second using the ROI covering the entire animal.
Carlet M., Völse K., Vergalli J., Becker M., Herold T., Arner A., Senft D., Jurinovic V., Liu W.H., Gao Y., Dill V., Fehse B., Baldus C.D., Bastian L., Lenk L., Schewe D.M., Bagnoli J.W., Vick B., Schmid J.P., Wilhelm A., Marschalek R., Jost P.J., Miething C., Riecken K., Schmidt-Supprian M., Binder V, & Jeremias I. (2021). In vivo inducible reverse genetics in patients’ tumors to identify individual therapeutic targets. Nature Communications, 12, 5655.