Table 1.

A large proportion of tumor cells can sustain the growth of murine lymphoid and myeloid malignancies. Cells from primary Eμ-myc pre-B/B lymphomas, Eμ-N-RAS thymic lymphomas, or PU.1–/– AML, all from mice on a C57BL/6 (Ly5.2+) background (>15 backcrosses), were transplanted into nonirradiated congenic C57BL/6 (Ly5.1+) recipient mice. To circumvent problems associated with injection of low cell numbers, we mixed the tumor cells with 106 congenic (C57BL/6-Ly5.1+) spleen cells as carriers. Shown are the fraction of recipients that developed tumors and the average time from transplantation to tumor development. No mice (0/24) injected with carrier spleen cells alone developed any tumor over a 100-day period. ND, not determined.

Recipients that developed tumors (days to kill)
105 cells103 cells102 cells10 cells
Eμ-myc B lymphoma
Case 1 3/3 (25) 3/3 (25) 3/3 (32) 2/2 (35)
Case 2 3/3 (21) 3/3 (23) 3/3 (24) 3/3 (24)
Case 3 Sca-1+ AA4.1hi 3/3 (21) 3/3 (21) ND 3/3 (17)
    Sca-1+ AA4.1lo 2/2 (17) 2/2 (28) 2/2 (28) 2/2 (40)
Eμ-N-RAS T lymphoma
Case 1 3/3 (28) 3/3 (42) 3/3 (28) 3/3 (28)
PU.1-/- AML
Case 1 1/1 (54) 2/2 (168) 1/2 (192) 0/2
Case 2 2/2 (84) 2/2 (85) 2/2 (224) 1/2 (114)
Case 3 1/1 (85) 2/2 (62) 2/2 (69) 2/2 (90)
Case 4 1/1 (30) 1/1 (37) 2/2 (79) 2/2 (88)