MBN transcription in sorted cell populations of IFN-α–treated patients and after in vitro stimulation of PBMCs by RT-PCR.

(A) PBMC- and MACS-enriched CD15⁺ cell fractions of 4 patients (UPNs 14-17) in complete hematological remission under IFN-α therapy. (B) Sorted CD14⁺ monocytic, CD3⁺T-lymphocytic, and CD19⁺ B-lymphocytic cell populations, as indicated, of 2 patients (UPN 17 and UPN 18) in complete hematological remission. (C) PBMCs of a healthy donor were cultured 48 hours without and for 24 hours or 48 hours in the presence of 1500 U/mL IFN-α. Also shown are unstimulated U937 positive control (U937) and a no-template control (–). (D) CD3, CD14, and CD19 cell populations were sorted on a Moflo cell sorter. Then, 0.2 to 0.3 × 10⁶cells of each population were seeded into media supplemented with 1500 U/mL IFN-α, 1 μM imatinib, or no supplements as indicated. At 24 hours after treatment, cells were harvested and MBN was expression assessed by RT-PCR. Panels B and C are each representative for experiments performed with material from 2 distinct donors/patients. For reference, β-actin gene transcription was assessed as depicted.