Generation of cytotoxic T lymphocytes by MHC class I ligands fused to heat shock cognate protein 70

• Published in: International immunology 2001-10, Vol.13 (10), p.1233-1242
• Main Authors: Udono, Heiichiro, Yamano, Taketoshi, Kawabata, Yuko, Ueda, Masakatsu, Yui, Katsuyuki
• Format: Article
• Language: English
• Subjects: Animals; antigen presentation; Antigens, Bacterial - immunology; Antigens, Neoplasm - immunology; APC antigen-presenting cell; Carrageenan - immunology; CD4 antigen; CD8 antigen; cellular immunity; CTL cytotoxic T lymphocyte; Drug Administration Routes; Epitopes; Escherichia coli; H-Y Antigen - immunology; Histocompatibility Antigens Class I - immunology; hsc70 heat shock cognate protein 70; HSC70 Heat-Shock Proteins; Hsc70 protein; hsp heat shock protein; HSP70 Heat-Shock Proteins - immunology; Mice; Mycobacterium - immunology; OVA ovalbumin; ovalbumin; Ovalbumin - immunology; peptide; Peptide Fragments - immunology; Plasmodium yoelii; Protozoan Proteins - immunology; Recombinant Fusion Proteins - immunology; stress protein; T-Lymphocytes, Cytotoxic - immunology; Tumor Cells, Cultured; vaccine; Vaccines, Synthetic - immunology
• ISSN: 0953-8178; 1460-2377
• DOI: 10.1093/intimm/13.10.1233

Immunization with gp96 and heat shock cognate protein 70 (hsc70) purified with in vivo bound naturally occurring peptides or bound to synthetic peptides by in vitro reconstitution has been shown to induce peptide-specific cytotoxic T lymphocytes (CTL). In addition, mycobacterial heat shock protein 70 covalently fused to ovalbumin (OVA)-derived fragments has been shown to generate MHC class I-restricted CTL responses. Here, we genetically fused five different CTL epitopes, including peptides derived from Plasmodium yoelii circumsporozoite protein, tumor antigens, HY antigen and OVA, to either the N- or C-terminus of murine hsc70 and expressed the resulting proteins in Escherichia coli. Vaccination with all five fusion proteins induced peptide-specific CTL, indicating that no cognate flanking regions of CTL epitopes are necessary for the immune response. The point of injection was crucial for CTL induction. CD4+ T cells were not required for the priming of CD8+ T cells and vaccination with bone marrow-derived dendritic cells pulsed with hsc70 fusion proteins also elicited CTL responses. Furthermore, by using deletion mutants of hsc70, we identified amino acid residues 280–385 of hsc70 as the region most critical for inducing the CTL response.