Modified J-chain
The present invention concerns modified recombinant J-chain polypeptides, binding molecules, such as antibodies comprising the same, and their uses.
1. An IgM, IgA, IgG/IgM, or IgG/IgA antibody, comprising a modified J-chain, wherein the modified J-chain comprises an extraneous binding moiety introduced into a native sequence J-chain of SEQ ID NO: 1 at one or more of the following locations:
(a) at or within about 10 amino acid residues from the C-terminus,
(b) at or within about 10 amino acid residues from the N-terminus, or
(c) in between cysteine residues 92 and 101,
wherein the IgG/IgM or IgG/IgA antibody is a hybrid antibody that can incorporate and form polymers with the modified J-chain.
2. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , wherein the extraneous binding moiety is a polypeptide introduced into the native human J-chain sequence of SEQ ID NO: 1 by direct or indirect fusion.
3. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 2 , wherein the extraneous binding moiety is introduced by indirect fusion through a peptide linker.
4. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 3 , wherein said peptide linker has a length that ranges from 1 to 20 amino acids.
5. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 4 , wherein said peptide linker is about 15 to 20 amino acids long.
6. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 5 , wherein said peptide linker is 15 amino acids long.
7. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 at the C-terminus.
8. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , wherein the extraneous binding moiety is introduced into the native human J-chain sequence of SEQ ID NO: 1 at the N-terminus.
9. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , 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.
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 by a chemical linker.
11. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 10 , 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, bis-active fluorine compounds, and any combination thereof.
12. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 9 , wherein the modified J-chain is modified by insertion of an enzyme recognition site, and by post-translationally attaching an extraneous binding moiety at the enzyme recognition site through a peptide or non-peptide linker.
13. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , wherein the extraneous binding moiety is selected from the group consisting of: antibodies, antigen-binding fragments of antibodies, antibody-drug conjugates, antibody-like molecules, antigen-binding fragments of antibody-like molecules, soluble and membrane-bound proteins, ligands, receptors, virus-like particles, protein toxins, enzymes, and alternative scaffolds.
14. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 13 , wherein the alternative scaffold is selected from the group consisting of: darpins, fibronectin domains, adnectins, and knottins.
15. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 13 , wherein the extraneous binding moiety comprises an antigen-binding fragment selected from the group consisting of: F(ab′) 2 , F(ab) 2 , Fab′, Fab, Fv, scFv, and single domain antibody.
16. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 15 , wherein the extraneous binding moiety comprises an antigen-binding fragment that is an scFv.
17. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , which is an IgA antibody.
18. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , which is mono-specific.
19. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 18 , which is bispecific.
20. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 18 , which is multi-specific.
21. The IgM, IgA, IgG/IgM, or IgG/IgA antibody of claim 1 , further comprising an additional extraneous binding moiety, wherein the additional extraneous binding moiety is a polypeptide introduced into the native human J-chain sequence of SEQ ID NO: 1 by direct or indirect fusion.