Analysis of the tissue distribution of CMP/GMP progeny and survival following A fumigatus infection. (A) Flow cytometric analysis of tissue neutrophils (Mac-1⁺Gr-1⁺) on D+8 identified the presence of donor CMP/GMP-derived cells (CD45.1⁺CD45.2^-). Although present in both bone marrow and blood, the donor cells constituted the majority of splenic neutrophils in comparison to host cells (CD45.1⁺CD45.2⁺). (B) Kaplan-Meier plot of mice infected with 3 × 10⁶ to 4 × 10⁶ cfu of A fumigatus following treatment with 5-FU only (○) or 5-FU plus 1 × 10³ CMPs and 2 × 10³ GMPs (⬡). The myeloid progenitors were infused 30 hours after 5-FU administration and the mice were infected 8 days after chemotherapy via intranasal instillation of A fumigatus conidia. The group that had received the CMP/GMP infusion (n = 41) had a significantly higher survival rate than the group treated with 5-FU only (n = 75) (56% and 33% respectively; P = .019). Animals that succumbed to infection at 2 to 4 days after instillation showed clinical evidence of disease, whereas those that survived appeared healthy throughout the observation period (30 to 60 days).