Endogenous production and proapoptotic properties of Δ¹²-PGJ₃. (A) Endogenous formation of PGD₃, Δ¹²-PGJ₃, and 15d-PGJ₃ in RAW264.7 macrophages (LC-UV trace; n = 3 for EPA-treated cells). (B) Representative LC-MS of Δ¹²-PGJ₃ containing eluates with characteristic fragmentation pattern. (C) Dose-response demonstrating the effect of Δ¹²-PGJ₃ on BCR-ABL⁺ LSCs compared with normal HSCs (MSCV-GFP⁺ HSCs). Cells were treated ex vivo with Δ¹²-PGJ₃ for 36 hours. Apoptosis was measured by annexin V staining. (D) Kit⁺Sca-1⁺Lin⁻BCR-ABL–GFP⁺ cells sorted from the BM and cultured ex vivo in medium containing Δ¹²-PGJ₃ (25nM) or vehicle control for 36 hours followed by flow cytometric analysis of GFP⁺ cells (n = 3). Means ± SEM are shown. * P < .005. Data are expressed as a percentage of input GFP⁺ cells. (E) Dose response of LSCs isolated from FV mice with indicated concentrations of Δ¹²-PGJ₃ at the end of 36 hours of incubation. Apoptosis of LSCs was examined by annexin V staining followed by flow cytometry. (F) FV-LSCs were cultured ex vivo with 25nM concentrations of each compound for 36 hours (n = 3). Means ± SEM shown. *P < .0001 compared with PGJ₃.