Figure 1.

Schematic representation of the expression vectors used in this study. All constructs were derived from pcDNA3. Plasmids pcDNA3:V_HCα2m(1) and pcDNA3:V_LCκ contain the original ORF for neomycin resistance (neo^R), pcDNA3Hygro:Jchain the ORF for hygromycin B resistance (hygro^R), and pcDNA3His:SC the ORF for histidinol resistance (his^R). The two black boxes called H-VDJ and L-VJ represent the genomic DNA coding for the murine heavy and light variable regions isolated from HNK-20 hybridoma. The other black boxes contain the human genomic region comprising the three α-chain domains, the human genomic region coding for the κ-chain, and the human cDNAs for the J chain and SC, respectively. Striped segments span the μ and κ enhancers obtained from mouse genomic fragments. The restriction sites used for the construction of the vectors are indicated.