Objective: To establish a novel leukemia cell line and characterize its biological characteristics.
Method: The cell line was established by liquid cell culture. The genetic marker was analyzed by R-banding and reverse transcriptase-polymerase chain reaction (RT-PCR), cell morphology by microscopy, electron microscopy and histochemical staining, cell surface antigen by monoclonal antibody, hemoglobin by hyperomethemoglobin measurement and electrophoresis, erythroid differentiation by benzidine-staining, and monocyte-macrophage differentiation by cell morphology and phagocytosis.
Results: A novel erythroleukemia cell line (HIE1), with original cell genetic marker (Ph chromosome, bcr/abl fusion gene rearrangement), was established from a CML patient in blast crisis, and has been passaged for over 60 generations. Myelomonocyte marker and hemoglycoprotein A were found on the cell surface. HIE1 cells contained hemoglobin, the same HbA and HbA(2) bands as in normal individuals were displayed by Hb electrophoresis. The benzidine positive HIE1 cells were induced after exposure to 3.6 x 10(-4) mmol/L Ara-C. When HIE1 cells were treated with 100 ng/ml PMA for 3 days, one third of the cells became spindle in shape, and 6.5% of the cells exert phagocytosis. The cells were classified into two types with Wright-staining: one showing light blue cytoplasm and a few of cells with basophilic granules, the other showing dark blue cytoplasm with vacuoles and pseudopods without granules. In addition, POX, SB, CE stains were negative, and AE, PAS, ACP stains positive. Colony formation of the cells was 37%, the cell doubling time was 22 - 24 hrs, and EB virus detection was positive.
Conclusion: A novel erythroleukemia cell line with bcr/abl fusion gene and characteristics of myelomonocytic and erythroid cells was established.