NK-cells but neither T nor B cells are obligatory for optimal CpG ODN-induced anti-AML responses.
B6 (A) or B6-SCID (B) mice (n = 10 per group) were treated with CpG 1585 or 2006, beginning on day −2 prior to the infusion of C1498 cell (A: 6 × 105 cells/mouse unless otherwise indicated; B: 2 × 105 cells/mouse). Cohorts of mice were given irrelevant, anti-NK or anti-CD4+CD8 mAbs, as indicated, according to “Materials and methods.” (A) CpG 2006 administration reduced tumorigenicity as compared with controls (P = .0008). Depletion of NK cells (P = .0054) but not T cells (P = .14) significantly reduced the anti-AML efficacy of CpG 2006, although CpG-treated NK-depleted recipients survived significantly (P = .0006) longer than non–CpG-treated controls. (B) B6-SCID mice treated with CpG 2006 but not CpG 1585 survived significantly longer after C1498 challenge than controls (P = .00 and .16, respectively). NK-depleted B6-SCID mice treated with CpG 2006 but not CpG 1585 survived significantly longer after C1498 challenge than controls (P = .0008 and .36, respectively).
