FPLC purification of recombinant cIFN-α expressed in auto-induction system on a DEAE-Sepharose column. (A) Protein elution profile (chromatogram). The profile clearly showed three peaks (fractions 8–11, 12–14, and 15–20). Numbers 1–28: number of collected fractions. (B) SDS-PAGE analysis of samples before and after cIFN-α purification. Lane M: lab-made protein molecular weight marker. Lane 1: cell lysate supernatant of auto-induced cells after 24 h incubation at 30°C. Lane 2: recovered cIFN-α protein after purification. Lane 3: cell lysate supernatant of uninduced cells.