Mouse splenic microenvironment alters BCL-2 dependency in LOUCY cells. (A) Representative flow cytometry plots of gating the hCD45⁺ phycoerythrin (PE) cells. Percentage of cytochrome c release is normalized to dimethyl sulfoxide (DMSO) as negative control and alamethicin (ALM) as positive control. (B) BH3 profile on LOUCY cells isolated from the spleen of vehicle- and ABT-199–treated mice (n = 3 mice each group; mean ± standard deviation [SD]). (C) The mRNA expression of BCL-2, BCL-XL, and MCL-1 in LOUCY cells isolated from the spleen of each mouse was measured by using quantitative reverse transcription polymerase chain reaction. The mRNA gene expression was normalized to HMBS, TBP, and UBC. n = 3 mice each group; mean ± SD. (D-E) Ex vivo sensitivity of hCD45⁺ sorted from the spleen of vehicle-treated and ABT-199–treated mice (n = 4 each group) to BH3 mimetics, as assessed by using CellTiter-Glo (Promega). (D) ABT-199 treatment for 16 hours. (E) WEHI-539 treated for 6 hours. The results represent the mean of 2 independent experiments, and error bars indicate ± SD. Two-way analysis of variance with Dunnett’s post hoc test was used for statistical analysis. *P ≤ .05, **P ≤ .01, ***P ≤ .001, ****P < .0001. APC, allophycocyanin; SSC-A, side-scattered light area.