Immune inducer containing polynucleotide-peptide conjugate and pharmaceutical composition containing same

An immunity-inducing agent composition comprising a polynucleotide-peptide conjugate or a pharmaceutically acceptable salt thereof,

• wherein the polynucleotide-peptide conjugate consists of:
• a single-chain polynucleotide or polynucleotide derivative comprising a CpG motif;
• a peptide;
• and a spacer which is covalently bonded at one end thereof to the polynucleotide or polynucleotide derivative and covalently bonded at the other end thereof to the peptide,
• wherein the peptide is a peptide modified by substituting one or more contiguous amino acids at the N-terminus of an MHC-binding peptide with an amino acid having a reactive functional group which allows for the formation of a covalent bond with the spacer, wherein the one or more contiguous amino acids contain no anchor residues for MHC binding,
• wherein the polynucleotide derivative is a polynucleotide comprising a modification for increasing nuclease resistance, and
• wherein the amino acid having a reactive functional group which allows for the formation of a covalent bond with the spacer is cysteine or an analogue thereof, wherein the analogue is an amino acid having a side chain containing thiol.