Design and production of novel tetravalent bispecific antibodies

We have produced novel bispecific antibodies by fusing the DNA encoding a single chain antibody (ScFv) after the C terminus (C(H)3-ScFv) or after the hinge (Hinge-ScFv) with an antibody of a different specificity, The fusion protein is expressed by gene transfection in the context of a murine variable region, Transfectomas secrete a homogeneous population of the recombinant antibody with two different specificities, one at the N terminus (anti-dextran) and one at the C terminus (anti-dansyl). The C(H)3-ScFv antibody, which maintains the constant region of human IgG3, has some of the associated effector functions such as long half-life and Fc receptor binding, The Hinge-ScFv antibody which lacks the C(H)2 and C(H)3 domains has no known effector functions.