Abstract: Herein is reported a method for determining a combination of antigen binding sites comprising the steps of (i) determining the binding specificity and/or affinity and/or effector function and/or in vivo half-life of a multitude of bispecific antibodies prepared by combining each member of a first multitude of antibody Fab fragments or scFv antibody fragments with each member of a second multitude of antibody Fab fragments or scFv antibody fragments, and a linker comprising at one of its termini the second member of the first binding pair and at the respective other terminus the second member of the second binding pair, whereby the first multitude specifically binds to a first cell surface molecule and the second multitude specifically binds to a second cell surface molecule, and (ii) choosing the bispecific antibody with suitable binding specificity and/or affinity and/or effector function and/or in vivo half-life and thereby determining a combination of antigen binding sites.

Abstract: The invention concerns an antibody composition which inhibits the binding of interleukin 2 to its high affinity receptor and contains (1) monoclonal antibodies against the &agr; chain of the interleukin 2 receptor and (2) monoclonal antibodies against the &bgr; chain of the interleukin 2 receptor, as well as a pharmaceutical agent which contains the antibody composition according to the present invention.

Abstract: The subject matter of the present invention are high-affinity monoclonal antibodies against MIA (Melanoma inhibitory activity) in native conformation, which can be used for the detection of malignant melanomas, their use for the detection of MIA as well as immunoassays for the detection of MIA.

Abstract: The invention concerns a melanoma-inhibiting protein, nucleic acid sequences coding for this protein, process for the isolation of this protein as well as its use for the production of a therapeutic agent.

Abstract: Chimeric monoclonal antibodies or fragments thereof are used according to the present invention in diagnostic tests for the quantitative immunological determination of substances in the blood or serum of patients. For the diagnostic detection of substances in serum or blood of patients by binding of two monoclonal antibodies R.sub.1 and R.sub.2 directed against the substance, of which the first antibody R.sub.1 is capable of binding to a solid phase or is already bound and the second antibody R.sub.2 carries a label, binding of the antibody R.sub.1 to the solid phase if desired, separation of the complex formed of R.sub.1, substance and R.sub.2 which is bound to the solid phase and detection via the labelling of the antibody R.sub.2, a chimeric monoclonal antibody or a fragment thereof is used at least for one of the antibodies R.sub.1 or R.sub.2.