A melanoma multiepitope polypeptide induces specific CD8+ T-cell response

• Published in: Cellular immunology 2007-11, Vol.250 (1), p.24-30
• Main Authors: Levy, Adva, Pitcovski, Jacob, Frankenburg, Shoshana, Elias, Orit, Altuvia, Yael, Margalit, Hanna, Peretz, Tamar, Golenser, Jacob, Lotem, Michal
• Format: Article
• Language: English
• Subjects: CD8-Positive T-Lymphocytes - drug effects; CD8-Positive T-Lymphocytes - immunology; Cell Separation; Cells, Cultured; Cytotoxic T cells; Dendritic Cells - drug effects; Dendritic Cells - immunology; DNA, Complementary - genetics; DNA, Complementary - pharmacokinetics; Drug Design; Electroporation; Enzyme Inhibitors - pharmacology; Epitopes, T-Lymphocyte - genetics; Epitopes, T-Lymphocyte - immunology; Epitopes, T-Lymphocyte - pharmacology; Escherichia - genetics; Humans; Immunotherapy - methods; Interferon-gamma - metabolism; Melanoma; Melanoma - genetics; Melanoma - immunology; Multiepitope; Peptides - genetics; Peptides - immunology; Peptides - pharmacology; Plasmids - genetics; Proteasome Endopeptidase Complex - metabolism; Proteasome Inhibitors; Proteins - genetics; Proteins - immunology; Proteins - pharmacology; T-Lymphocytes, Cytotoxic - drug effects; T-Lymphocytes, Cytotoxic - immunology
• ISSN: 0008-8749; 1090-2163
• DOI: 10.1016/j.cellimm.2008.01.001

Strategies using epitope-based vaccination are being considered for melanoma immunotherapy, in an attempt to overcome failure of other modalities. In the present study, we designed and produced a multiepitope polypeptide for melanoma (MEP-mel), which contains three repeats of four antigenic epitopes (gp100: 209–217 (210M); gp100: 280–288 (288V); Mart1: 26–35 (27L); tyrosinase: 368–376 (370D). The peptides were attached to each other by linkers containing sequences recognized by the proteasome, to improve protein cleavage and antigen presentation. The results show that peptide-specific T cells produced IFN-γ when stimulated with MEP-mel-transfected dendritic cells. The presentation of peptides by MEP-mel-transfected dendritic cells was proteasome-dependent and was more long-lasting than the presentation of exogenously delivered native peptides. When dendritic cells were loaded with MEP-mel protein, weak cross presentation was induced. The production of multiepitope molecules based on several peptides linked by sequences sensitive to proteasomal cleavage represents a promising new tool for the improvement of cancer immunotherapy.