Table 1

4T1 mammary tumor cells metastasize more rapidly to the lungs and liver of BALB/c.IFNγ−/− mice than of wild-type BALB/c mice

BALB/c and BALB/c.IFNγ−/− mice were inoculated s.c. in the abdominal mammary gland with 7 × 103 4T1 cells and were killed on day 35. The number of lung and liver metastatic cells was determined using the clonogenic assay.

BALB/cBALB/c.IFNγ−/−
Mice with >10,000 lung metastases29% (5/17)64% (7/11)
Mice with >100 liver metastases53% (9/17)73% (8/11)