Correlation of CD11b mRNA at diagnosis with percentage of blasts at day 8. Blast cells from paired day 8 to day 0 samples were purified by flow sorting, and mRNA was isolated, amplified, and hybridized to oligonucleotide chips. CD11b mRNA expression at diagnosis in arbitrary units (AUs; ●) correlates significantly with blast percentage in PB at day 8 (Spearman coefficient = 0.61, P = .007). The CD11b expression at day 8 (○) is consistently increased and does not correlate with blast percentage at day 8 (Spearman coefficient = 0.38, P = .12).