[Cytotoxicity of cytotoxic T lymphocytes induced by keratin 19-sensitized dendritic cells against MCF-7 cells in vitro].

Objective: To investigate the cytotoxicity of cytotoxic T lymphcytes (CTL) induced by keratin 19 (K19)-sensitized dendritic cells (DC) against MCF-7 cells in vitro.

Methods: DC isolated from peripheral blood mononuclear cells were cultured in vitro and sensitized by K19 peptide to generate specific CTL. The phenotypes and intracytoplasm cytokine of DC were analyzed by flow cytometry. Mixed leukocyte responses were evaluated by (3)H-TdR incorporation assay. The T cells were generated by DC pulsed with K19 antigen and T cell cytotoxicity was measured by (51)Cr release assay.

Results: The DCs derived from peripheral blood mononuclear cells expressed high levels of CD40, CD86, CD80 and CD83. Mixed leukocyte responses induced by the DCs pulsed with K19 was stronger than that induced by naive DCs (P<0.01). The cytotoxicity rate of CTL induced by the sensitized DCs was higher than that of CTL induced by naive DCs (P<0.01). The cytotoxity activity was enhanced by increasing the effector/target ratio (P<0.01).

Conclusion: After sensitization with K19 antigen, the DCs can stimulate T cell proliferation and induce cytotoxicity activity against MCF-7 cells. Increased effector/target ratio may enhance the cytotoxity activity. Sensitized DCs possess the potential for amplification in immunotherapy of carcinoma.