C1498/B7-2 induced immunologic memory against C1498 and C1498/B7-1
| Priming tumor3-150 . | Challenge tumor (1 × 106cells)3-151 . | No. tumor progressors/injected mice (%)3-152 . | MST ± SD (d)3-153 . |
|---|---|---|---|
| None | C1498 | 5/5 (100) | 27 ± 7 |
| C1498/B7-2 | C1498 | 2/14 (14)3-155 | 19 ± 1 |
| None | C1498/B7-1 | 6/6 (100) | 34 ± 5 |
| C1498/B7-2 | C1498/B7-1 | 0/5 (0)3-155 | — |
| C1498/B7-2 and C1498 | C1498/B7-1 | 0/12 (0)3-155 | — |
| Priming tumor3-150 . | Challenge tumor (1 × 106cells)3-151 . | No. tumor progressors/injected mice (%)3-152 . | MST ± SD (d)3-153 . |
|---|---|---|---|
| None | C1498 | 5/5 (100) | 27 ± 7 |
| C1498/B7-2 | C1498 | 2/14 (14)3-155 | 19 ± 1 |
| None | C1498/B7-1 | 6/6 (100) | 34 ± 5 |
| C1498/B7-2 | C1498/B7-1 | 0/5 (0)3-155 | — |
| C1498/B7-2 and C1498 | C1498/B7-1 | 0/12 (0)3-155 | — |
C1498 challenge experiment: C1498/B7-2 “primed” B6 mice had rejected a subcutaneous challenge of 1 × 106live C1498/B7-2 tumor cells 16 to 22 weeks before this experiment. On day 0, a group of naive B6 mice and the C1498/B7-2-primed mice were challenged subcutaneously with 1 × 106 parental C1498 tumor cells.
C1498/B7-1 challenge experiment: C1498/B7-2-primed B6 mice had rejected a subcutaneous challenge of 1 × 106 C1498/B7-2 tumor cells 11 weeks earlier, whereas B6 mice primed to both C1498/B7-2 and C1498 had rejected challenges of live C1498/B7-2 (1 × 106) 36 to 43 weeks earlier and of live C1498 tumor cells (1 × 106) 21 weeks earlier. On day 0 of this experiment, naive B6 mice and primed mice noted above were challenged subcutaneously with C1498/B7-1.
C57BL/6 mice were injected subcutaneously with 1 × 106 live tumor cells, as indicated.
Percentages of mice that developed progressive tumors within 60 days after tumor injection.
MST of mice that developed tumor.
Significantly different from the naive control groups challenged with either C1498 or C1498/B7-1 (Fischer exact test;P ≤ .002).