Expression plasmid encoding human IFNα2b cDNA. A) The pYD7-IFNα2b expression plasmid has been used to generate the D9 clone. (Amp) ampicillin, (Blast) blasticidin, (CMV) cytomegalovirus promoter, (enh MLP) adenovirus major late promoter, (IFNα2b) human codon-optimized sequence for human IFNα2b gene, (pA) polyadenylation sequence, (pMB1ori) bacterial origin of replication, (Puro) puromycin, (OriP) Epstein-Barr virus origin of replication, (SV40pA) simian virus 40 polyadenylation sequence, (TPL) adenovirus tripartite leader.B) Amino acid sequence of human IFNα2b. Signal peptide is underlined. The two intramolecular disulfide bridges are C1-C98 and C29-C138. The glycan-linked threonine (Thr106) is underscored.