Patent ID: 6015884
Filing Date: 2000-01-18
Classification: A61K,A61P,C07K,C12N

Abstract:
A first molecular complex which comprises at least four fusion proteins, wherein:(a) two first fusion proteins comprise (i) an immunoglobulin heavy chain, wherein the immunoglobulin heavy chain comprises a variable region, and (ii) an extracellular domain of a first transmembrane polypeptide; and(b) two second fusion proteins comprise (i) an immunoglobulin light chain and (ii) an extracellular domain of a second transmembrane polypeptide; wherein the fusion proteins associate to form the first molecular complex, wherein the first molecular complex comprises two ligand binding sites, each ligand binding site formed by the extracellular domains of the first and second transmembrane polypeptides, wherein the affinity of the first molecular complex for a cognate ligand is increased compared to a second molecular complex consisting of the extracellular domain of the first transmembrane polypeptide and the extracellular domain of the second transmembrane polypeptide.