AN INTEGRATED VECTOR SYSTEM FOR THE EUKARYOTIC EXPRESSION OF ANTIBODIES OR THEIR FRAGMENTS AFTER SELECTION FROM PHAGE DISPLAY LIBRARIES

Phage display is now an established method to select antibody fragment s specific for a wide range of diverse antigens. In particular, isolat ion of human monoclonal antibodies has become a reality and for most p urposes bacterial expression of the selected recombinant antibody frag ments is sufficient. However, there are some cases where the expressio n of complete human immunoglobulin in mammalian cells is, if not essen tial, at least desirable. For this reason we have designed and constru cted a set of mammalian expression vectors which permit facile and rap id cloning of antibody genes for both transient and stable expression in mammalian cells. Immunoglobulin genes may be cloned into these expr ession vectors as V regions or as Fabs for expression as either comple te antibodies or as Fab fragments, using restriction sites which are r are in human V genes. All the important elements in the vectors - prom oter, leader sequence, constant domains and selectable markers - are f lanked by unique restriction sites, allowing simple substitution of el ements. The vectors have been evaluated using the variable regions fro m the neutralizing anti-nerve growth factor (NGF) antibody, alpha D11, and the V regions from 2E10, a scFv Selected from a scFv phagemid lib rary.