Influence of immunotherapy with autologous dendritic cells on innate and adaptive immune response in cancer.

The objective of this study was to evaluate some of the mechanisms involved in the activation of the immune system in patients with advanced-stage cancer (n = 7) who received an autologous dendritic cell vaccine. We examined the immune response mediated by macrophages (CD14+), natural killer cells (CD56+), and B lymphocytes (CD19+) by flow cytometry and assessed the expression of Th1 (IFN-γ, TNF-α, IL-2, and IL-12), Th2 (IL-4), and Treg (TGF-ß) cytokines by flow cytometry and an enzyme-linked immunosorbent assay. The CD14+ TNF-α+ population was significantly increased (P < 0.04) when patients received the vaccine; IL-2 expression in both NK cells and in B lymphocytes was increased after a transient initial increase showed a nearly significant decrease (P < 0.07 and P < 0.06 respectively), whereas the CD19+ and CD56+ populations did not show significant changes. Dendritic cell-based immunotherapy led to increased secretion of IFN-γ and IL-12 and reduced secretion of TGF-ß. In conclusion, it is likely that the autologous dendritic cell vaccine stimulated the immune cells from the peripheral blood of patients with cancer and generally increased the production of Th1 cytokines, which are related to immunomodulatory responses against cancer.

The role of T lymphocytes in cancer patients undergoing immunotherapy with autologous dendritic cells.

INTRODUCTION: Cancer stems from mutations in specific genes that induce uncontrolled cell proliferation. Dendritic cells (DCs) are important immunologic cells and play a crucial role in the induction of an antitumour response. PATIENTS AND METHODS: We examined the immune response mediated by T lymphocytes, helper T cells, cytotoxic T cells, and regulatory T cells, as well as the cytokines [interleukin (IL)-2, IL-12, interferon (IFN)-γ, tumour necrosis factor (TNF)-α and IL-10], produced by these cell populations, in cancer patients (N = 7) undergoing immunotheraphy with autologous DCs. RESULTS: We observed an initial increase in T helper cells (CD4+) expressing IL-2, IFN-γ, IL-12, TNF-α, and IL-10 after initiation of treatment, with statistically significant for the cytokines IL-2, TNF-α and IL-10. A similar significant effect was observed for IL-2-expressing cytotoxic T cells (CD8+). The percentage of total T cells (CD3+) remained elevated throughout immunotherapy. Regulatory T cells (CD25+/FOXP3+) only showed high percentage of their maximum value when analyzed the pretreatment levels, with statistically significant. CONCLUSION: Immunotherapy with DCs stimulated the immune response, as evidenced by an increase in percent fluorescence of most cell populations investigated during the specified treatment period.