12th International Conference of Pharmaceutical Sciences

The tumor microenvironment has an immunosuppressor character that induces dendritic cells (DCs) to an immature/tolerogenic profile. Therefore, to resolve this cellular disfunction, vaccine using DCs (DCVs) pulsed with tumor lysate has been tested and shows potent capability to induce cytotoxic T lymphocyte. However, the effect of DCVs may be enhanced by immunoadjuvants. In this way, the present study aims to investigate the immunomodulatory effect of Sildenafil (a phosphodiesterase-5 inhibitor whose effects on immune system have been demonstrated) on the effector responses of DCs in vitro. For this, bone marrow precursors of C57BL6 mice were differentiated into DCs and treated with breast cancer cell (EO771) lysate and/or Sildenafil; cytokines and surface activation markers were evaluated. Results showed that DCs treated with lysate plus Sildenafil were more activated than cells treated with lysate alone. These results suggest that Sildenafil may act as an immunoadjuvant with probable application in the breast cancer treatment.