Type I IFN-based preconditioning permits HSC replacement in WT mice. (A) WT (CD45.1−CD45.2+) mice, either untreated (white, n = 6) or treated with poly(I:C) alone (light gray, n = 6), 5-FU alone (dark gray, n = 6), or poly(I:C) and 5-FU (black, n = 6), were given transplants of 5 × 106 whole BM cells from congenic mice (CD45.1+CD45.2+). The results from 2 independent experiments are shown. Data shown are the mean ± SD of donor-derived B cells (B220+) and myeloid (Gr1+ plus CD11b+) cells, 7 to 8 months after BMT. (B) WT (CD45.1−CD45.2+) mice were treated with LD-TBI alone (white) or with polyI:C and LD-TBI (light gray), 5-FU and LD-TBI (dark gray), or poly(I:C) with 5-FU and LD-TBI (black), then given transplants of 5 × 106 whole BM cells from congenic mice (CD45.1+CD45.2+). The TBI dose was 1.5 Gy (left, n = 3 each) or 3 Gy (right, n = 6 each). The results from 2 independent experiments are shown. Data shown are the mean ± SD of donor-derived B cells (B220+) and myeloid (Gr1+ plus CD11b+) cells 7 to 8 months after BMT. *P < .05; **P < .01; ***P < .001; . ns, not significant.
