CD1c+ and CD303+ dendritic cells in peripheral blood, lymph nodes and tumor tissue of patients with non-small cell lung cancer.

Dendritic cells (DCs) are the most potent antigen presenting cells, which can stimulate a cellular immune response against malignant tumor cells. Many authors have described the phenomenon of tumor infiltration by dendritic cells and emphasized an immunosuppressive tumor influence on DC function. In the present study, we examined the presence of myeloid CD1c+ (BDCA-1+) dendritic cells and lymphoid/plasmacytoid CD303+ (BDCA-2+) dendritic cells in peripheral blood, lymph nodes and cancer tissue of patients with non-small cell lung cancer (NSCLC). Fifty male patients treated surgically for NSCLC stages I-IIIa without neoadjuvant chemotherapy were included. Employing a multiparameter flow cytometry for CD1c, CD19, CD123 and CD303, we observed an accumulation of immature DCs in the tissues involved in the neoplasmatic process with the predominance of lymphoid/plasmacytoid over myeloid DCs. Moreover, in peripheral blood NSCLC patients had a significantly lower percentage of CD1c+ DCs than healthy donors. Our results suggest that NSCLC cells might hamper the maturation of DCs, thus escaping an efficient immune response.