35 Expression of Antibody Fab Fragments and Whole Immunoglobulin in Mammalian Cells

The technologies described in this volume enable the isolation of recombi- nant antibodies (Abs) from libraries of variable regions (Fvs) or Fabs displayed on the surface of filamentous phage by fusion to a structural protein (1 -7 ). Production of selected Abs in sufficient quantity for further evaluation often requires the transfer of their coding sequences to vectors specfiically designed for expression in eukaryotic cells. For Fab and/or immunoglobulin G (IgG) expression, these systems either employ separate plasmids for the heavy-chain (HC) and light-chain (LC) sequences or a single plasmid in which both HC and LC cassettes are expressed.