Antibodies comprising C-terminal light chain polypeptide extensions and conjugates and methods of use thereof

The present disclosure provides light chain polypeptides that include a C-terminal extension, as well as antibodies and antibody conjugates containing such modified light chain polypeptides, where the C-terminal extension includes one or more cysteine residues. Conjugates that include an antibody of the present disclosure conjugated to an agent via the cysteine residue of the C-terminal amino acid extension are also provided. The present disclosure further provides nucleic acids encoding an antibody light chain polypeptide that includes a C-terminal amino acid extension including a cysteine residue. Pharmaceutical compositions including the antibodies or conjugates of the present disclosure are also provided, as are methods of making and use of the modified antibodies and conjugates of the present disclosure.