Presence of leukemia-specific CTLs in CML. Bone marrow from H8 mice was transduced with BCR/ABL-GFP or cotransduced with NUP98/HOXA9-GFP and BCR/ABL-neo and injected into 4.5 Gy irradiated C57BL/6 mice. (A-B) The frequency of gp33-specific CTLs was analyzed by tetramer staining (A) and intracellular IFN-γ and TNF-α staining (B) in the blood of mice that eliminated H8-cpCML and H8-bcCML, in mice with progressive H8-cpCML and H8-bcCML, in naive C57BL/6, and in LCMV-immune mice. (C) Splenocytes of H8-cpCML and H8-bcCML mice were isolated 20 days after BMT and analyzed in a standard ⁵¹Cr-release assay (gp33-pulsed target cells [filled symbols]; nonpulsed target cells [open symbols]). CTL activity is given as mean ± SEM of 4 CML mice (●), naive C57BL/6 (♦), and LCMV-immune mice (■). (D) H8-cpCML and H8-bcCML mice and C57BL/6 controls were infected with 200 pfu of LCMV intravenously. Eight days after LCMV infection, the frequency of gp33-specific and np396-specific CTLs was analyzed in the blood and spleen by tetramer staining. One representative experiment of 2 is shown.