A vaccine composition comprising a fusion protein for inducing enhanced pathogen antigen-specific T cell responses is disclosed. The fusion protein comprises: (a) an antigen-presenting cell (APC)-binding domain or a CD91 receptor-binding domain, located at the N-terminus of the fusion protein； (b) a translocation peptide of 34-112 amino acid residues in length, comprising an amino acid sequence that is at least 90% identical to SEQ ID NO: 4, 2, 3, or 6, located at the C-terminus of the APC-binding domain or the CD91 receptor-binding domain； and (c) an antigen of a pathogen, located at the C-terminus of the translocation peptide； (d) a nuclear export signal, comprising the amino acid sequence of SEQ ID NO: 13； and (e) an endoplasmic reticulum retention sequence, located at the C-terminus of the fusion protein.
