VERSATILE VECTORS FOR TRANSIENT AND STABLE EXPRESSION OF RECOMBINANT ANTIBODY MOLECULES IN MAMMALIAN-CELLS

We have developed new cassette expression vectors for the cloning of a ny intact V-region gene followed by any C-region gene, Both the heavy- and light chain Vectors harbor a strong hCMV promoter, restriction si te cassettes for cloning of both V- and C-region genes, transcription termination signals, fl-ori for single stranded DNA (ssDNA) synthesis, selection marker for Neomycin and SV40 ori for transient expression. The vectors accept V-H and V-L chain genes obtained by RT-PCR. Reampli fication of the V genes is then performed with a new set of primers wh ich are designed specifically for each individual V gene. Cloning into the vectors is aided by restriction sites located just outside the V- gene coding region, thus keeping the V-genes intact. The vectors also contain cloning sites for the exchange of genomic C-genes so that the resulting Ig genes may code for complete antibodies, antibody fragment s or fusion proteins, A simple subcloning step permits the expression of both heavy and light chain genes from one single vector, thus avoid ing co-transfection of the two vectors, The usefulness of the vectors was confirmed by construction of mouse-human chimeric antibodies. The V-genes were derived from a hybridoma cell line. TP-3, and was combine d with human C kappa, C gamma 3 and C gamma 1 genes as well as with C( H)1 gamma 3. High yields of recombinant antibody products in NSO cells were obtained. Transient expression was also demonstrated.