| abstract |
Provided herein are trispecific and/or trivalent binding proteins comprising four polypeptide chains forming three antigen binding sites that specifically bind to one or more target proteins, wherein a first polypeptide forming a binding protein is provided herein. The pair has dual variable domains with cross orientation and the second pair of polypeptides has a single variable domain that forms a single antigen binding site. In some embodiments, the binding protein comprises a binding site that binds a CD28 polypeptide, a binding site that binds a CDS polypeptide, and a binding site that binds a third polypeptide, such as a tumor target protein. The present invention also relates to methods for preparing trispecific and/or trivalent binding proteins and to the use of such binding proteins. |