Antibody Conjugates and Methods of Making and Using the Same

An immunoglobulin (Ig) kappa light chain polypeptide comprising, in a constant region, an amino acid sequence selected from:

• i) SEQ ID NO:
• 6, SEQ ID NO:
• 16, SEQ ID NO:
• 29, SEQ ID NO:
• 30, SEQ ID NO:
• 40, and SEQ ID NO:
• 42;
• or
• ii) a sequence having, exclusive of the sequence LCTPSR (SEQ ID NO:
• 158), at least 90% sequence identity to a sequence from entry (i);
• wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO:
• 158) is oxidized to fGly.

An immunoglobulin (Ig) kappa light chain polypeptide comprising, in a constant region, an amino acid sequence selected from the group consisting of:

• i) SEQ ID NO:
• 6, SEQ ID NO:
• 16, SEQ ID NO:
• 29, SEQ ID NO:
• 30, SEQ ID NO:
• 40, and SEQ ID NO:
• 42,
• wherein the cysteine residue in the sequence LCTPSR (SEQ ID NO:
• 158) is oxidized to fGly.