title: Monitoring of anti-vaccine CD4 T cell frequencies in melanoma patients vaccinated with a MAGE-3 protein.
abstract: Quantitative evaluation of T cell responses of patients receiving antitumoral vaccination with a protein is difficult because of the large number of possible HLA-peptide combinations that could be targeted by the response. To evaluate the responses of patients vaccinated with protein MAGE-3, we have developed an approach that involves overnight stimulation of blood T cells with autologous dendritic cells loaded with the protein, sorting by flow cytometry of the T cells that produce IFN-gamma, cloning of these cells, and evaluation of the number of T cell clones that secrete IFN-gamma upon stimulation with the Ag. An important criterion is that T cell clones must recognize not only stimulator cells loaded with the protein, but also stimulator cells transduced with the MAGE-3 gene, so as to exclude the T cells that recognize contaminants generated by the protein production system. Using this approach it is possible to measure T cell frequencies as low as 10(-6). We analyzed the frequencies of anti-vaccine CD4 T cells in five metastatic melanoma patients who had been injected with a MAGE-3 protein without adjuvant and showed evidence of tumor regression. Anti-MAGE-3 CD4 T cells were detected in one of the five patients. The frequency of the anti-MAGE-3 CD4 T cells was estimated at 1/60,000 of the CD4 T cells in postvaccination blood samples, representing at least an 80-fold increase in the frequency found before immunization. The frequencies of one anti-MAGE-3 CD4 T cell clonotype were confirmed by PCR analysis on blood lymphocytes. The 13 anti-MAGE-3 clones, which corresponded to five different TCR clonotypes, recognized the same peptide presented by HLA-DR1.
authors.affiliation: Ludwig Institute for Cancer Research, Brussels Branch and Cellular Genetics Unit, Université de Louvain, Brussels, Belgium.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Zhaojun
authors.initials: Z
authors.lastname: Sun
authors.forename: Hugues
authors.initials: H
authors.lastname: Nicolay
authors.forename: Ralf G
authors.initials: RG
authors.lastname: Meyer
authors.forename: Nicolina
authors.initials: N
authors.lastname: Renkvist
authors.forename: Vincent
authors.initials: V
authors.lastname: Stroobant
authors.forename: Jurgen
authors.initials: J
authors.lastname: Corthals
authors.forename: Javier
authors.initials: J
authors.lastname: Carrasco
authors.forename: Alexander M M
authors.initials: AM
authors.lastname: Eggermont
authors.forename: Marie
authors.initials: M
authors.lastname: Marchand
authors.forename: Kris
authors.initials: K
authors.lastname: Thielemans
authors.forename: Thomas
authors.initials: T
authors.lastname: Wölfel
authors.forename: Thierry
authors.initials: T
authors.lastname: Boon
authors.forename: Pierre
authors.initials: P
authors.lastname: van der Bruggen
mesh_terms: D000595:Amino Acid Sequence; D017951:Antigen Presentation; D000951:Antigens, Neoplasm / Q000276:immunology* / Q000378:metabolism / Q000627:therapeutic use; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology*; D019496:Cancer Vaccines / Q000276:immunology* / Q000378:metabolism / Q000627:therapeutic use; D002461:Cell Line, Transformed; D002469:Cell Separation; D002999:Clone Cells; D018920:Coculture Techniques; D006131:Growth Inhibitors / Q000276:immunology / Q000378:metabolism / Q000627:therapeutic use; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D018655:Lymphocyte Count; D008545:Melanoma / Q000276:immunology* / Q000473:pathology* / Q000517:prevention & control / Q000556:secondary; D008969:Molecular Sequence Data; D015166:Monitoring, Immunologic / Q000379:methods*; D009363:Neoplasm Proteins / Q000276:immunology* / Q000378:metabolism / Q000627:therapeutic use; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D006131:Growth Inhibitors; C072013:MAGEA3 protein, human; D009363:Neoplasm Proteins; D007371:Interferon-gamma