mRNA expression of various genes including C/EBPε in hematopoietic cell lines. The mRNA was amplified using RT-PCR. Each PCR reaction included primers specific for the analyzed gene and primers for β-actin as an internal control. PCR conditions yielded amplification in the linear range. PCR products were blotted, hybridized using either cDNA probes or internal oligonucleotides specific for the amplified genes, and autoradiography was performed. All samples were examined at least twice for all genes.