title: Restoration of tumor-specific HLA class I restricted cytotoxicity in tumor infiltrating lymphocytes of advanced breast cancer patients by in vitro stimulation with tumor antigen-pulsed autologous dendritic cells.
abstract: Breast tumor infiltrating lymphocytes (TIL) are enriched in tumor-specific cytotoxic T lymphocytes (CTL), and may represent a superior source of CTL compare to peripheral blood lymphocytes (PBL), for adoptive T cell immunotherapy of breast cancer. However, the immunocompetence of TIL and the possibility to consistently restore their tumor-specific lytic activity in vitro remains an open issue. In this study we evaluated the potential of tumor antigen-pulsed fully mature dendritic cell (DC) stimulation in restoring tumor-specific cytotoxicity in anergic TIL populations from advanced breast cancer patients. In addition we have compared tumor-specific T cell responses induced by tumor antigen-loaded DC stimulation of TIL to responses induced from PBL. Although TIL were consistently non-cytotoxic after isolation or culture in the presence of interleukin-2 (IL-2), in matched experiments from three consecutive patients, tumor-lysate-pulsed DC-stimulated CD8+ T cell derived from TIL were found to be significantly more cytotoxic than PBL (p < 0.05). In addition, cytotoxicity against autologous tumor cells was more significantly inhibited by an anti-HLA class I (W6/32) MAb in TIL compared to PBL (p < 0.05). CTL populations derived from TIL and PBL did not lyse autologous EBV-transformed lymphoblastoid cell lines, and showed negligible cytotoxicity against the NK-sensitive cell line K562. Furthermore, in both CD8+ T cell populations the majority of the tumor-specific CTL exhibited a Th1 cytokine bias (IFN-gamma(high)/IL-4(low)). Taken together, these data show that tumor lysate-pulsed mature DC can consistently restore tumor-specific lytic activity in non-cytotoxic breast cancer TIL. These results may have important implications for the treatment of chemotherapy resistant breast cancer with active or adoptive immunotherapy.
mesh_terms: D000328:Adult; D000951:Antigens, Neoplasm / Q000276:immunology*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000276:immunology*; D016827:CD8 Antigens / Q000032:analysis / Q000276:immunology; D018929:Cell Culture Techniques; D016923:Cell Death; D003713:Dendritic Cells / Q000276:immunology*; D019008:Drug Resistance, Neoplasm; D005260:Female; D005805:Genes, MHC Class I / Q000276:immunology*; D006680:HLA Antigens; D006801:Humans; D016219:Immunotherapy, Adoptive; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D016827:CD8 Antigens; D006680:HLA Antigens