The decrease of serum osteocalcin concentrations is correlated to the number of CFU-GM mobilized into peripheral blood. Serum osteocalcin concentrations were calculated for each individual patient or donor by dividing serum osteocalcin contrations measured at either day 6 of G-CSF (○), day 9 of SCF + G-CSF (▪), or day 10 of IL-3 + G-CSF (▴) administration by serum osteocalcin concentrations before mobilization. The number of CFU-GM was analyzed with peripheral blood mononuclear cells collected on either day 6 of G-CSF, day 9 of SCF + G-CSF, or day 10 of IL-3 + G-CSF. Slope and significance levels were calculated using the nonparametric Spearman correlation test.