Multivalent glycopeptide constructs and uses thereof

A method of inducing antibodies in a subject, wherein the antibodies are capable of specifically binding with human tumor cells, which comprises administering to the subject an immunogenic glycoconjugate, wherein the immunogenic glycoconjugate comprises a multi-antigenic glycopeptide having a peptidic backbone made up of at least five amino acid residues, wherein five or more of said amino acids are independently:

• wherein
• L1 is a substituted or unsubstituted aliphatic or heteroaliphatic moiety;
• and
• A is a carbohydrate determinant selected from the group consisting of Globo-H, STN, Tn, TF, Gb5, and GM2;
• wherein at least one occurrence of A is Gb5 or GM2.

A method comprising the steps of:

• (a) incubating an immunogenic carrier protein with a crosslinking agent to provide a crosslinking-ready immunogenic carrier protein;
• (b) treating a thiol-containing biomolecule with a suitable disulfide reducing reagent;
• and
• (c) combining the crosslinking-ready immunogenic carrier protein with the thiol-containing biomolecule under suitable conditions to provide an immunogenic carrier protein-biomolecule conjugate.

A method comprising the steps of:

• (a) treating a thiol-containing biomolecule with a suitable disulfide reducing reagent;
• (b) incubating the thiol-containing biomolecule with a crosslinking agent to provide a crosslinking-ready biomolecule;
• and
• (c) combining the crosslinking-ready biomolecule with an immunogenic carrier protein under suitable conditions to provide an immunogenic carrier protein-biomolecule conjugate.

A glycoconjugate having the structure:

• wherein
• each A is independently a carbohydrate determinant found on tumor cells;
• each L1 is independently a substituted or unsubstituted aliphatic or heteroaliphatic moiety;
• each R1 is independently a natural or unnatural amino acid side chain;
• R2 is hydrogen or an amino protecting group;
• Rc is an immunogenic carrier;
• the crosslinker is a moiety derived from a bifunctional crosslinking reagent capable of conjugating a reactive moiety on the linker with a reactive moiety on the immunogenic carrier;
• the linker is a covalent bond, an oligoester fragment comprising from 2 to about 20 hydroxy acyl residues, a peptidic fragment comprising from 2 to about 20 amino acyl residues, a linear or branched chain alkyl or aryl carboxylic ester, or an optionally substituted, bivalent C1-20 saturated or unsaturated, straight or branched, hydrocarbon chain, wherein one to six methylene units of the chain are independently replaced by —CR2—, —NR—, —N(R)C(O)—, —C(O)N(R)—, —N(R)SO2—, —SO2N(R)—, —O—, —C(O)—, —OC(O)—, —C(O)O—, —S—, —SO—, —SO2—, —C(═S)—, —C(═NR)—, —N═N—, or —C(═N2)—;
• each R is independently hydrogen or an optionally substituted group selected from C1-6 aliphatic, phenyl, a 3-7 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered heteroaryl ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• m is from 5-20;
• p is from 0-20;
• q is 0 or 1;
• and
• t is the number of glycopeptide groups attached to the immunogenic carrier and is greater than 200.

A glycopeptide having the structure:

• wherein
• each A is independently a carbohydrate determinant found on tumor cells, wherein at least one occurrence of A is Gb5;
• each L1 is independently a substituted or unsubstituted aliphatic or heteroaliphatic moiety;
• each R1 is independently a natural or unnatural amino acid side chain;
• R2 is hydrogen or an amino protecting group;
• R3 hydrogen or an immunogenic carrier;
• the crosslinker is a moiety derived from a bifunctional crosslinking reagent capable of conjugating a reactive moiety on the linker with a reactive moiety on the immunogenic carrier;
• the linker is a covalent bond, an oligoester fragment comprising from 2 to about 20 hydroxy acyl residues, a peptidic fragment comprising from 2 to about 20 amino acyl residues, a linear or branched chain alkyl or aryl carboxylic ester, or an optionally substituted, bivalent C1-20 saturated or unsaturated, straight or branched, hydrocarbon chain, wherein one to six methylene units of the chain are independently replaced by —CR2—, —NR—, —N(R)C(O)—, —C(O)N(R)—, —N(R)SO2—, —SO2N(R)—, —O—, —C(O)—, —OC(O)—, —C(O)O—, —S—, —SO—, —SO2—, —C(═S)—, —C(═NR)—, —N═N—, or —C(═N2)—;
• each R is independently hydrogen or an optionally substituted group selected from C1-6 aliphatic, phenyl, a 3-7 membered saturated or partially unsaturated carbocyclic ring, a 3-7 membered saturated or partially unsaturated monocyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a 5-6 membered heteroaryl ring having 1-3 heteroatoms independently selected from nitrogen, oxygen, or sulfur;
• m is from 5-20;
• p is from 0-20;
• and
• q is 0 or 1.