Presence of p210^BCR/ABL in normal CD34⁺ cells delays apoptosis.

p210-eGFP– or eGFP-transduced GFP⁺ CD34⁺ cells (10⁴) from 4 cord blood samples were plated in serum-free medium with or without 500 pg/mL rhIL-3 for 2 days. The number of CFCs was determined in fresh and 2-day culture cells by plating 10⁴ cells or their culture progeny in methylcellulose assay. Percentage CFCs that survived the 2-day culture was calculated as (no. CFCs in 2-day progeny/no. CFCs in fresh cells) × 100. Comparison between p210-eGFP– and eGFP-transduced GFP⁺CD34⁺ cells (P = .001). ▪, eGFP/no IL-3; ▵, eGFP/+IL-3; ♦, p210-eGFP/no IL-3; ○, p210-eGFP/+IL-3.