A recombinant cell line expressing a form of the Y13-259 anti-p21ras antibody which binds protein A and may be produced as ascites.

We have recently reported the molecular cloning of the immunoglobulin genes encoding the variable regions of the rat anti-p21ras antibody, Y13-259. These genes were reassembled into expression vectors supplying DNA sequences encoding human gamma 1 and kappa constant domains, as well as the leader sequence for antibody secretion, thus yielding Hu-Y13-259, a secretory anti-p21ras antibody containing human constant regions. We now report the creation of a recombinant cell line, NS0/Hu-Y13-259/B6, secreting high levels of the Hu-Y13-259 Ig. The antigen specificity of this recombinant antibody was demonstrated to be identical to that of the parental Y13-259, i.e. the amino acid sequence 60-76 of the p21ras protein. Unlike the parental cell line, the recombinant cells could be grown as ascites in mice, allowing the production of large quantities of the protein A-binding Hu-Y13-259 antibody.