[Detecting phospho-signaling protein of bone marrow leukemia cells by phospho-signaling flow cytometry]

The purpose of this study was to establish the phospho-specific flow cytometry (phospho-flow) to detect the phosphorylated signaling proteins of leukemia cells and to evaluate its useful value in leukemia study. The bone marrow of leukemia children was collected, and treated by phospho-flow of extracted mononuclear cells (MNC) and phospho-flow of directly fixed bone marrow (BM) respectively. In phospho-flow of extracted MNC, the MNC extracted from BM were fixed and permeabilized, then were cultured with P-AKT and P-ERK1/2, finally were analyzed by flow cytometry. In phospho-flow of directly fixed BM, the BM was treated with fixation/lysis buffer and 90% methanol, then were incubated with the surface CD antibody, P-AKT and P-ERK1/2, finally the treated BM cells were analyzed by flow cytometry. The results showed that the positive rates of P-AKT and P-ERK1/2 in MNC treated by phospho-flow of extracted MNC of 26 leukemia children were 46.2% and 30.8% respectively, while the positive rates of P-AKT and P-ERK1/2 in BM treated by phospho-flow of directly fixed BM were 50.0% and 38.5% respectively. The comparison of positive rates of P-AKT and P-ERK1/2 between the 2 treatment protocol showed no difference (p > 0.05). It is concluded that the phospho-flow of directly fixed BM established by our laboratory can be used to analyze the signaling proteins of leukemia cells.