Immunosuppressive properties of human PD-1+ PDL-1+ dendritic cell from Lymph Nodes Aspirates of NSCLC patients

Dendritic cells DCs play a pivotal role in homeostasis of the immune system. The tumor microenviroment impairs the proper function of DCs. Despite the progress in anticancer immunotherapy, there are still many unresolved issues. Among them the immunomodulatory propeties of DCs in lung cancer are of interes. We investigated the differences of DCs subsets and with expression of immunomodulating and costimulatory molecules: PD-1, PD-L1 and CD80 in metastatic, non-metastatic LNs aspirates and peripheral blood PB. LNs aspirates were obtained during EBUS/TBNA procedure of 14 patients with primary NSCLC. The cells were analysed by flow cytometry. We reported the higher percentage of DCs in metastatic than in non-metastatic LNs and PB (0.324% vs 0.042% vs 0.036% p We report for the first time that DCs cells show increased expression of PD-1 and PD-L1 molecules that can interact with T lymphocytes in tumor suppressory microenvironment. It can be assumed that mature DCs infiltrating metastatic LNs can develop into DCRegs, which are involved in suppression of anti-tumor response.