Local Radiation Therapy of B16 Melanoma Tumors Increases the Generation of Tumor Antigen-Specific Effector Cells That Traffic to the Tumor

摘要: Immunotherapy of cancer is attractive because its potential for specificity and limited side effects. The efficacy this approach may be improved by providing adjuvant signals an inflammatory environment immune cell activation. We evaluated antitumor responses in mice after treatment OVA-expressing B16-F0 tumors with single (15 Gy) or fractionated (5 x 3 doses localized ionizing radiation. Irradiated had cells greater capability to present tumor Ags specific T that secreted IFN-gamma upon peptide stimulation within tumor-draining lymph nodes than nonirradiated mice. Immune activation correlated increase the number CD45(+) infiltrating dose irradiated compared Similarly, increased numbers tumor-infiltrating lymphocytes lysed targets. Peptide-specific were directed against both class I II MHC-restricted OVA peptides OVA(257-264) OVA(323-339), respectively, as well endogenous B16 tyrosinase-related protein 2(180-188). Adoptive transfer studies indicated Ag-specific most likely due enhanced trafficking these site. Together results suggest radiation can generation effector their