SP profiles from human bone marrow, KG1a and A549 cells.

(A) Typical SP profile derived from human bone marrow (BM). Vertical axis shows blue Hoechst fluorescence, horizontal axis shows red Hoechst fluorescence. The SP cells are indicated within the gate. (B) SP profile of KG1a cells. (C) A549 cells exhibiting a significant SP. (D) Expression of ABCG2, MDR1, and MRP1 in cell lines. GAPDH-normalized RT reactions from each cell line were subjected to 36 cycles (MDR1, MRP1) and 37 cycles (ABCG2, GAPDH) of amplification with specific primers for each cDNA. The bottom row confirms similarGAPDH levels in the normalized RT reactions.