Studies on human leukemic B-cell line Part Ⅱ. Serial transplantation of human leukemic B-cell line (BALL-1) into hamsters

A human leukemic B-cell line, which was designated as BALL-1, was recently established in our laboratory. In this experiment, BALL-1 cells were serially transplanted into antilymphocyte serum (ALS)-treated newborn Syrian hamsters. When 1.0-8.5×10(7) viable cells were inoculated intraperitoneally, all of them developed invasive tumors 12-26 days after implantation. All the hamsters except one had 0.2-8.0ml of milky ascites containing 0.9-11.0×10(8) tumor cells/ml. Histologically, invasion of the tumor cells was observed in many abdominal organs and in subcutaneous tissue. Progression to leukemia was common (24/25), and the percentage of the tumor cells in the peripheral blood ranged between 2 and 91% . Morphological features, surface markers, and chromosome constitutions of the tumor cells were identical to those of BALL-1 cells. These findings show thast BALL-1 cells were serially transplantable into the experimental animals possessing the characteristics of human leukemic B-cells. To our knowledge, this is the first report of successful heterotransplantation of a human leukemic B-cell line. This animal model will provide a new advantage in many aspects of leukemia research.