Effect of GM-CSF and G-CSF on IL-10–induced inhibition of spontaneous CFU-GM growth. Unseparated PB-MNCs (2 × 10⁵) were cultured in methylcellulose containing 30% FCS and IMDM. Either GM-CSF (100 U/mL) or G-CSF (100 U/mL) was added to cultures containing IL-10 (10 ng/mL). Colony growth was assessed after 14 days. The mean colony numbers (±SEM) are given from six independent experiments.