Table 1: Spontaneous lung metastases formation by 4T1/Ido1+, 4T1/Ido1− or NT-5/Ido1+, NT-5/Ido1− tumors in immunocompetent and immunodeficient mice.

Mice1No. of spontaneous pulmonary metastases
4T1/Ido1+ tumors4T1/Ido1− tumors

BALB/c56; (41, 51, 56, 66, 182)21; (6, 12, 21, 24, 29)*
SCID-beige54; (23, 24, 54, 75, 164)69; (33, 54, 64, 69, 69, 71, 77, 92)

Mice1NT-5/Ido1+ tumorsNT-5/Ido1− tumors

FVB/N6; (0, 2, 3, 5, 6, 7, 8, 11, 14)1.5; (0, 0, 0, 0, 3, 4, 8, 10)*
SCID-beige25; (11, 12, 16, 24, 25, 26, 28, 32, 44)*13; (0, 3, 12, 13, 13, 13, 14, 15)

1BALB/c and SCID-beige were inoculated s.c. with 2.5 × 104 4T1/Ido1+ or 4T1/Ido1− tumor cells. FVB/N and SCID-beige were inoculated s.c. with 5 × 106 NT-5/Ido1+ or NT-5/Ido1− tumor cells. When tumors reached about 2 cm in diameter, lungs were harvested and fixed in the Bounce solution. Metastases were counted under dissecting microscope. *Significantly ( ) differ from all other groups.