title: Recombinant heat shock protein 70 in combination with radiotherapy as a source of tumor antigens to improve dendritic cell immunotherapy.
abstract: Local radiotherapy (RT) plus intratumoral dendritic cell (DC) injection can mediate immunological response. We hypothesized that co-injection of exogenous recombinant heat shock protein 70 (rHsp70) in combination with RT-DC could be as effective as co-injection of HSP-peptide for evoking specific immune response. rHsp70-prostate-specific antigen (rHSP70C'-PSA) and α-fetoprotein (rHSP70C'-AFP) were used to compare specific response. Growth inhibition of the tumor and the systemic anti-tumor immune response were measured on CT26/PSA and CT26/AFP mice model. Intratumoral co-injection of rHsp70 and DC into the irradiated tumor site induced a more potent anti-tumor immune response than injection of DC alone. rHsp70 was as effective as rHsp70C'-PSA or rHsp70C'-AFP in inducing a tumor-specific cytotoxic T lymphocyte response or tumor growth delay. These results demonstrate that co-administration with rHsp70 and RT could be a simple and effective source of tumor antigens to achieve RT-DC immunotherapy protocol and easy to apply in clinical use.
authors.affiliation: Department of Radiation Therapy and Oncology, Shin Kong Wu Ho-Su Memorial Hospital Taipei, Taiwan ; Department of Animal Science, National Ilan University Ilan, Taiwan.
authors.forename: Yu-Shan
authors.initials: YS
authors.lastname: Wang
authors.forename: Shih-Jen
authors.initials: SJ
authors.lastname: Liu
authors.forename: Su-Chen
authors.initials: SC
authors.lastname: Huang
authors.forename: Chao-Chun
authors.initials: CC
authors.lastname: Chang
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Huang
authors.forename: Weng-Lam
authors.initials: WL
authors.lastname: Fong
authors.forename: Mau-Shin
authors.initials: MS
authors.lastname: Chi
authors.forename: Kwan-Hwa
authors.initials: KH
authors.lastname: Chi
keywords: dendritic cells; heat shock protein 70; immunotherapy; radiotherapy; tumor microenvironment