Modified j-chain

Abstract

The present invention concerns modified recombinant J-chain polypeptides, binding molecules, such as antibodies comprising the same, and their uses.

What is claimed is: 
     
         1 . An IgM, IgA, IgG/IgM, or IgG/IgA antibody, or an antigen-binding fragment thereof, comprising a modified J-chain, wherein the modified J-chain comprises an extraneous binding moiety introduced into a native sequence J-chain. 
     
     
         2 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 1 , wherein the native sequence J-chain is the native human J-chain sequence of SEQ ID NO: 1, or a functional fragment thereof. 
     
     
         3 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 2 , wherein the native sequence J-chain is the native human J-chain sequence of SEQ ID NO: 1. 
     
     
         4 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 3 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 by direct or indirect fusion. 
     
     
         5 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 4 , wherein the binding moiety is introduced by indirect fusion through a peptide linker. 
     
     
         6 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 5 , wherein the indirect fusion is through a peptide linker at or around the C- and/or N-terminus of the binding moiety. 
     
     
         7 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 6 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 at or around the C-terminus. 
     
     
         8 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 7 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 within about 10 residues from the C-terminus. 
     
     
         9 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 6 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 at or around the N-terminus. 
     
     
         10 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 9 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 within about 10 amino acid residues from the N-terminus. 
     
     
         11 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 5 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence in between cysteine residues 92 and 101 of SEQ ID NO: 1. 
     
     
         12 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 5 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 at or near a glycosylation site. 
     
     
         13 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 5 , wherein said peptide linker is about 10 to 20 amino acids long. 
     
     
         14 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 13 , wherein said peptide linker is about 15 to 20 amino acids long. 
     
     
         15 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 14 , wherein said peptide linker is 15 amino acids long. 
     
     
         16 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 3 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 by chemical or chemo-enzymatic derivatization. 
     
     
         17 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 16 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 by a chemical linker. 
     
     
         18 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 17 , wherein the chemical linker is a cleavable or non-cleavable linker. 
     
     
         19 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 18 , wherein the cleavable linker is a chemically labile linker or an enzyme-labile linker. 
     
     
         20 . The IgM, IgA, IgG/IgM, or IgG/IgA antibody of  claim 18 , wherein the linker is selected from the group consisting of N-succinimidyl-3-(2-pyridyldithio) propionate (SPDP), succinimidyl-4-(N-maleimidomethyl) cyclohexane-1-carboxylate (SMCC), N-succinimidyl-4-(2-pyridylthio) pentanoate (SPP), iminothiolane (IT), bifunctional derivatives of imidoesters, active esters, aldehydes, bis-azido compounds, bis-diazonium derivatives, diisocyanates, and bis-active fluorine compounds. 
     
     
         21 - 95 . (canceled)