BV173 engrafted in NSG mice, treated with dasatinib 10 mg/kg daily ± ESKM 100 µg twice weekly for 25 days, beginning on day 6. The error bars show the fifth and 95th percentiles. (A) Logarithmic tumor growth curve as measured by BLI. (B) Control and dasatinib-alone mice were sacrificed on day 30 for evaluation of ESKM binding and HLA-A*02:01 expression by flow cytometry. BV173 cells were harvested from the livers of all NSG mice immediately after cessation of therapy. Live hCD19⁺ cells (confirmed BV173) were evaluated for BB7 (HLA-A*02:01) and ESK staining and compared with BV173 in culture. (C) BLI imaging from day 27, showing persistence of leukemia at the end of therapy in dasatinib-treated mice and eradication of leukemic signal in mice receiving combination therapy. (D) The BLI image of the dasatinib + ESKM group on day 55, 24 days after cessation of therapy, showing focal lymphoid relapse. (E) Dasatinib + ESKM–treated mice dissected and reimaged individually to localize tumor. The organs were removed and imaged separately for precise tumor localization. Mouse 1: Primary tumor in the lymph node, with small liver metastasis detected. Mouse 3: Primary tumor in the stomach with focal liver metastasis and small renal metastasis. Mouse 4: Tumor seen in the left upper quadrant, but unable to be isolated by organ excision. Mouse 4: Diffuse right lung tumor, unable to visualize right upper quadrant tumor seen in prior imaging.