RESUMO
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the common malignancies, characterized by poor response to conventional therapeutic options. Immunotherapy with dendritic cells (DCs)-vaccines is one of the most successful strategies used for the treatment of HCC. However, the methods applied in the preparation of antigen-loaded DCs are important factors for optimization of DCs vaccines. PURPOSE: The present study was conducted to investigate the effect of HCC-whole tumor cell lysate prepared using rapid repetitive freeze-thaw cycles on the immunogenicity of DCs and evaluate the ability of whole tumor cell lysate-pulsed DCs vaccine to induce a specific cytotoxic T lymphocytes (CTLs) response against HepG2 cell line. METHODS: Immature DCs generated from peripheral blood monocytes were randomized into two groups: control DCs and whole tumor cell lysate-pulsed DCs. Phenotypic analysis of the DCs' cell maturation marker CD83 and co-stimulatory molecule CD86 was performed. HCC-specific cytotoxic activity of CD8+ CTLs was measured in vitro. RESULTS: Loading of DCs with necrotic whole cell lysate resulted in non-significant changes in DCs' expression of CD83, but a significant increase in expression of CD86. In addition, CD8+ CTLs stimulated with whole tumor cell lysate-pulsed DCs showed a high cytotoxic activity that specifically attack HepG2 cells. CONCLUSION: Our findings indicated that pulsation of DCs with whole tumor cell lysate prepared by repetitive freeze-thaw cycles could efficiently enhance the ability of DCs to induce proliferation and clonal expansion of CD8+ CTLs. Data herein, also indicated that whole tumor cell lysate-pulsed DCs triggers a specific CD8+ CTLs against HCC tumor cells.
