Antibodies, binding fragments, and methods of use

An isolated monoclonal antibody or an antigen-binding fragment thereof wherein the monoclonal antibody or antigen-binding fragment specifically binds to the carbohydrate antigen SSEA4 having the structure

• Neu5Acα2→3Galβ1→3GalNAcβ1→3Galα1→4Galβ1→4Glcβ1, wherein the antibody or antigen-binding fragment thereof comprises an H-CDR1, an H-CDR2, an H-CDR3, an L-CDR1, an L-CDR2, and an L-CDR3,
• i) the H-CDR1 having the sequence of SEQ ID No. 10, in which positions 1 or 5 of SEQ ID No. 10 are optionally substituted with Ser and Thr, respectively;
• ii) the H-CDR2 having the sequence of SEQ ID No. 11, in which positions 1, 4, or 13 of SEQ ID No. 11 are optionally substituted with Ala;
• iii) the H-CDR3 having the sequence of SEQ ID No. 12;
• in which position 3 of SEQ ID No. 12 is optionally substituted with Arg;
• iv) the L-CDR1 having the sequence of SEQ ID No. 15;
• in which position 6 of SEQ ID No. 15 is optionally substituted with Ile or Ala;
• v) the L-CDR2 having the sequence of SEQ ID No. 16, in which position 3 of SEQ ID No. 16 is optionally substituted with Tyr;
• and
• vi) the L-CDR3 having the sequence of SEQ ID No. 17, in which positions 3 or 6 of SEQ ID No. 17 are optionally substituted with Ala and Phe, respectively.

An isolated monoclonal antibody or an antigen-binding fragment thereof wherein the monoclonal antibody or antigen-binding fragment specifically binds to the carbohydrate antigen SSEA4 having the structure

• Neu5Acα2→3Galβ1→3GalNAcβ1→3Galα1→4Galβ1→4Glcβ1, wherein the antibody or antigen-binding fragment thereof comprises an H-CDR1, an H-CDR2, an H-CDR3, an L-CDR1, an L-CDR2, and an L-CDR3,
• i) the H-CDR1 having the sequence of SEQ ID No. 10, in which a conservative amino acid substitution has been made at positions 1 and 5 of SEQ ID No. 10;
• ii) the H-CDR2 having the sequence of SEQ ID No. 11, in which a conservative amino acid substitution has been made at positions 1 and 4 of SEQ ID No. 11, and a non-conservative amino acid substitution has been made at position 13 of SEQ ID No. 11;
• iii) the H-CDR3 having the sequence of SEQ ID No. 12;
• in which a non-conservative amino acid substitution has been made at position 3 of SEQ ID No. 12;
• iv) the L-CDR1 having the sequence of SEQ ID No. 15;
• in which a conservative amino acid substitution has been made at position 6 of SEQ ID No. 15;
• v) the L-CDR2 having the sequence of SEQ ID No. 16, in which a conservative amino acid substitution has been made at position 3 of SEQ ID No. 16;
• and
• vi) the L-CDR3 having the sequence of SEQ ID No. 17, in which a conservative amino acid substitution has been made at positions 3 and 6 of SEQ ID No. 17.

An isolated monoclonal antibody or an antigen-binding fragment thereof wherein the monoclonal antibody or antigen-binding fragment specifically binds to the carbohydrate antigen SSEA4 having the structure

• Neu5Acα2→3Galβ1→3GalNAcβ1→3Galα1→4Galβ1→4Glcβ1, wherein the antibody or antigen-binding fragment thereof comprises an H-CDR1, an H-CDR2, an H-CDR3, an L-CDR1, an L-CDR2, and an L-CDR3,
• i) the H-CDR1 having the sequence of SEQ ID No. 10, in which a conservative amino acid substitution has been made at positions 1 or 5 of SEQ ID No. 10;
• ii) the H-CDR2 having the sequence of SEQ ID No. 11, in which a conservative amino acid substitution has been made at positions 1 or 4 of SEQ ID No. 11, and a non-conservative amino acid substitution has been made at position 13 of SEQ ID No. 11;
• iii) the H-CDR3 having the sequence of SEQ ID No. 12 in which a non-conservative amino acid substitution has been made at position 3 of SEQ ID No. 12;
• iv) the L-CDR1 having the sequence of SEQ ID No. 15;
• in which a conservative amino acid substitution has been made at position 6 of SEQ ID No. 15;
• v) the L-CDR2 having the sequence of SEQ ID No. 16, in which a conservative amino acid substitution has been made at position 3 of SEQ ID No. 16;
• and
• vi) the L-CDR3 having the sequence of SEQ ID No. 17, in which a conservative amino acid substitution has been made at positions 3 or 6 of SEQ ID No. 17.