Patent ID: 6180370
Filing Date: 2001-01-30
Classification: A61K,A61P,C07K

Abstract:
A method of producing a humanized immunoglobulin which specifically binds to an antigen, the method comprising:providing a cell containing DNA segments encoding humanized light and heavy chain variable regions; andexpressing the DNA segments in the cell to produce the humanized immunoglobulin;wherein the cell containing the DNA segments was produced by:(1) comparing the sequence of a donor immunoglobulin heavy chain variable region against a collection of sequences of human heavy chain variable regions;(2) selecting a human heavy chain variable region from the collection of human heavy chain variable regions to provide an acceptor heavy chain variable region, wherein the selected variable region framework is at least 65% identical to the donor immunoglobulin heavy chain variable region framework, wherein percentage sequence identity is determined by aligning amino acids in said frameworks by Kabat numbering;(3) synthesizing the DNA segment encoding the humanized heavy chain variable region, comprising complementarity determining regions (CDRs) from the donor immunoglobulin heavy chain variable region and a variable region framework from the selected acceptor heavy chain variable region;(4) introducing the DNA segment encoding the humanized immunoglobulin heavy chain variable region and the DNA segment encoding the humanized immunoglobulin light chain variable region into the cell,wherein the humanized immunoglobulin heavy chain variable region framework comprises at least 70 amino acid residues identical to those in the acceptor immunoglobulin heavy chain variable region framework.