Antibody conjugates and methods of making and using the same
Antibodies that include a sulfatase motif-containing tag in a constant region of an immunoglobulin (Ig) light chain polypeptide are disclosed. The sulfatase motif can be converted by a formylglycine-generating enzyme (FGE) to produce a formylglycine (fGly)-modified Ig light chain polypeptide. An fGly-modified Ig light chain polypeptide of the antibody can be covalently and site-specifically bound to a moiety of interest to provide an antibody conjugate. The disclosure also encompasses methods of production of such tagged Ig light chain polypeptides, fGly-modified Ig light chain polypeptides, and antibody conjugates, as well as methods of use of same.
1. An immunoglobulin (Ig) kappa light chain polypeptide comprising, in a constant region, an amino acid sequence selected from:
i) SEQ ID NO: 2, SEQ ID NO: 4, SEQ ID NO: 17, SEQ ID NO: 18, SEQ ID NO: 26, SEQ ID NO: 28, SEQ ID NO: 31, SEQ ID NO: 37, SEQ ID NO: 44, and SEQ ID NO: 45;
wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
2. The Ig kappa light chain polypeptide of claim 1 , wherein the fGly is covalently bound to a payload.
3. The Ig kappa light chain polypeptide of claim 2 , wherein the fGly is covalently bound to the payload via a hydrazone, oxime, semicarbazone, alkyl, alkenyl, acyloxy, hydrazinyl-indolyl, hydrazinyl-imidazoyl, hydrazinyl-pyrrolyl, hydrazinyl-furanyl or a pyrazalinone linkage.
4. The Ig kappa light chain polypeptide of claim 2 , wherein the fGly is covalently bound to the payload via a linking group.
5. The Ig kappa light chain polypeptide of claim 4 , wherein the linking group comprises a 4-aminopiperidine derivative (4AP).
6. The Ig kappa light chain polypeptide of claim 2 , wherein the payload is a drug, a detectable label, a water-soluble polymer, a viral fusion inhibitor, or a synthetic peptide.
7. The Ig kappa light chain polypeptide of claim 6 , wherein the drug is a small molecule drug.
8. The Ig kappa light chain polypeptide of claim 7 , wherein the small molecule drug is a cancer chemotherapeutic agent.
9. The Ig kappa light chain polypeptide of claim 8 , wherein the cancer chemotherapeutic agent is an alkylating agent, a nitrosourea, an antimetabolite, an antitumor antibiotic, a vinca alkaloid, or a steroid hormone.
10. The Ig kappa light chain polypeptide of claim 6 , wherein the water-soluble polymer is poly(ethylene glycol).
11. The Ig kappa light chain polypeptide of claim 6 , wherein the detectable label is an imaging agent.
12. A recombinant nucleic acid comprising a nucleotide sequence encoding the Ig kappa light chain polypeptide of claim 1 .
13. A recombinant expression vector comprising the nucleic acid of claim 12 , wherein the nucleotide sequence encoding the Ig kappa light chain polypeptide is operably linked to a promoter.
14. A host cell genetically modified to express the Ig kappa light chain polypeptide of claim 1 .
15. The host cell of claim 14 , genetically modified to express a formylglycine generating enzyme (FGE), in a manner sufficient to convert the Ig kappa light chain polypeptide into an fGly-modified Ig kappa light chain polypeptide.
16. The host cell of claim 15 , wherein the host cell is a mammalian cell.
17. An antibody comprising the Ig kappa light chain polypeptide of claim 1 .
18. The antibody of claim 17 , wherein the antibody specifically binds a tumor antigen on a cancer cell.
19. A formulation comprising: the antibody of claim 18 and a pharmaceutically acceptable excipient.
20. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 2, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
21. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 4, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
22. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 17, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
23. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 18, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
24. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 26, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
25. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 28, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
26. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 31, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
27. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 37, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
28. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 44, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.
29. The Ig kappa light chain polypeptide of claim 1 , comprising, in the constant region, the amino acid sequence of SEQ ID NO: 45, wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO: 158) is oxidized to fGly.