STABLE MULTIVALENT ANTIBODY
The present invention relates to a multivalent antibody comprising multiple heavy chain variable regions of antibody linked to each other via a linker comprising an amino acid sequence encoding an immunoglobulin domain or a fragment thereof.
1 . A method for producing a multivalent antibody comprising four antigen recognition sites, wherein said method comprises:
(1) culturing a transformant comprising DNA encoding said multivalent antibody in a culture medium, to produce and accumulate the multivalent antibody in a culture; and
(2) recovering the multivalent antibody from the culture,
wherein said multivalent antibody comprises four light chain polypeptides each comprising a light chain variable region, wherein said multivalent antibody further comprises two heavy chain polypeptides each comprising two heavy chain variable regions linked to each other via a linker, and wherein all of said light chain polypeptides are the same,
wherein each of said heavy chain variable regions is complexed with one of said light chain polypeptides to form the antigen recognition sites, wherein said multivalent antibody binds to two different epitopes,
and wherein said linker consists of a CH1 domain originating from an IgM or IgG4 subclass, or consists of a CH1 domain fragment of 14 or more amino acids in which position 14 of said fragment is a cysteine, said fragment originating from an IgM or IgG4 subclass.
2 . The method of claim 1 , wherein said DNA encoding said multivalent antibody is present within a recombinant vector in said transformant.
3 . The method of claim 1 , wherein the amino acid sequence of the linker is an amino acid sequence selected from the group consisting of SEQ ID NOs: 311 and 334-361.
4 . The method of claim 1 , wherein the amino acid sequence of the CH1 fragment is an amino acid sequence selected from the group consisting of SEQ ID NOs: 362 to 375.
5 . The method of claim 1 , wherein the N-end of one of the heavy chain variable regions is linked to the C-end of another heavy chain variable region via the linker.
6 . The method of claim 5 , wherein the N-end of the linker is coupled to the C-end of one of the heavy chain variable regions and the C-end of the linker is coupled to the N-end of another heavy chain variable region.
7 . The method of claim 1 , wherein the transformant is a mammalian cell.
8 . The method of claim 7 , wherein the mammalian cell is a CHO cell.