TABLE 2.
Interleukin-10 (IL-10) enhances the antitumor effect of recombinant fowlpox virus
| Mean no. of pulmonary metastases
|
|||||
|---|---|---|---|---|---|
| Experiment | Tumor used | Virus used | Dose (PFU) | −IL-10 | +IL-10 |
| 1 | CT26.CL25 | FPV.wt | 107 | >250 | >250 |
| CT26.WT | FPV.bg40k | 107 | >250 | >250 | |
| CT26.CL25 | FPV.bg40k | 107 | 45a | 24a | |
| 2 | CT26.CL25 | FPV.wt | 106 | >250 | >250 |
| CT26.WT | FPV.bg40k | 106 | >250 | >250 | |
| CT26.CL25 | FPV.bg40k | 106 | 72a | 4b | |
| 3 | CT26.CL25 | FPV.wt | 105 | >250 | >250 |
| CT26.WT | FPV.bg40k | 105 | >250 | >250 | |
| CT26.CL25 | FPV.bg40k | 105 | >250 | 4b | |
BALB/c mice (five per group) were treated with recombinant fowlpox virus expressing β-gal (FPV.bg40k) or wild-type fowlpox virus (FPV.wt) at a dose of 107 plaque-forming units (PFU) (experiment 1), 106 PFU (experiment 2), or 105 PFU (experiment 3) by tail vein injection 3 days after intravenous administration of 5 × 105 CT26.CL25 (β-gal-expressing) tumor cells or CT26.WT (non-β-gal-expressing). IL-10 (1 μg i.p.) was started 12 hours after virus and continued daily for 5 days. FPV.bg40k reduced the mean number of pulmonary metastases in mice bearing the CT26.CL25 tumor when administered at 107 PFU or 106 PFU (a). IL-10 did not increase the response when 107 PFU virus was used, but did reduce the number of metastases compared to FPV.bg40k alone at 106 PFU and 105 PFU (a).
p ≤ 0.05 (Wilcoxon t test).
p ≤ 0.05 (Wilcoxon t test).