pH-dependent antibodies targeting the transferrin receptor and methods of use thereof to deliver a therapeutic agent

A pH-dependent antibody that binds an antigen with high affinity at a first pH and rapidly dissociates at a second pH, wherein the antigen is a transferrin receptor (TfR), wherein the association at the second pH/the first pH is less than 20%, and wherein the pH-dependent antibody comprises at least two consecutive histidine residues at a single complementarity determining region (CDR) is disclosed.