Effect of mature dendritic cells primed with autologous tumor antigens from patients with epithelial ovarian cancer on stimulation of the cytotoxic immune response in culture of mononuclear cells

Use of antigen-primed dendritic cells for inducing antitumor immune responses in vitro in patients with non-small cell lung cancer

Cancer is associated with a reduction in immature and mature circulating dendritic cells (DCs), and with an impaired migratory capacity, compared with healthy donors. Therefore, modern approaches to the in vitro generation of DCs loaded with tumor antigens and their use for inducing antitumor immune responses in vivo are being investigated. The purpose of the present study was to investigate the phenotypic and functional characteristics of peripheral blood DC subsets in patients with non-small cell lung cancer (NSCLC), and the development of an antitumor cytotoxic response by mononuclear cells (MNCs) from patients using in vitro generated antigen-primed DCs. Heparinized peripheral venous blood samples were obtained from 10 healthy donors and 20 patients with a histologically verified diagnosis of NSCLC. The ability of antigen-activated DCs to stimulate the activity of MNCs against autologous tumor cells was evaluated using a cytotoxic test. Peripheral blood DC subsets from patients with NSCLC were identified to be decreased and to exhibit an impaired ability to mature, compared with healthy donors. Furthermore, DCs generated from MNCs from patients with NSCLC were able to stimulate a specific cytotoxic response when loaded with autologous tumor lysates or RNA and matured, in vitro. A perforin and granzyme B-dependent mode of cytotoxicity was primarily induced. The ability of DCs loaded with tumor antigens to increase the cytotoxic activity of MNCs against NSCLC cells in vitro indicates the effective induction and co-stimulation of T lymphocytes by the generated DCs.

Modern strategies and capabilities for activation of the immune response against tumor cells

Dendritic cells are professional antigen-presenting cells and the most potent stimulators of various immune responses, such as antitumor responses. Modern studies have not shown an effective antitumor immune response development in patients with malignant tumors. The major cause is the decrease in functional activity of dendritic cells in cancer patients through irregularities in the maturation process to a functionally active form and in the antigen presentation process to naive T lymphocytes. This review describes the main stages of cellular antitumor immune response induction in vitro, aimed at resolving the problems that are blocking the full functioning of dendritic cells, and additional stimulation of antitumor immune response.