Murine Disseminated Leukemia Experiments

Mice were intravenously injected with 2 × 10⁶ NALM6-GL via the retro-orbital route. After 3 days, mice were infused with 4 × 10⁶ Hu19-28z or Hu19-828z total T cells. Any difference in the percentage of CAR expressing T cells between the two CARs was normalized by adjusting the total number of T cells infused for one group. Bioluminescence images of the mice were taken on the day of CAR T cell infusion and every 4 days thereafter. Imaging was done as follows: mice were intraperitoneally injected with 15 mg/mL of luciferin (Goldbio) in 200 μL of PBS. Bioluminescence images were taken 10 min after luciferin injection, while the mice were under anesthesia with 3% isoflurane. Images were captured using Xenogen IVIS Imaging System with Living Imaging software. Ventral images were captured at 30 s exposures on a 24 cm field of view and at binning factor 4. Bioluminescence was quantified through region of interest analysis over the whole mouse excluding the tail. Bioluminescence signals were given as photons per second per square centimeter per steradian.