Identification of a New Subset of Myeloid Suppressor Cells in Peripheral Blood of Melanoma Patients With Modulation by a Granulocyte-Macrophage Colony-Stimulation Factor–Based Antitumor Vaccine

摘要: Purpose Phenotypic and functional features of myeloid suppressor cells (MSC), which are known to serve as critical regulators antitumor T-cell responses in tumor-bearing mice, still poorly defined human cancers. Here, we analyzed subsets with suppressive activity present peripheral blood metastatic melanoma patients evaluated their modulation by a granulocyte-macrophage colony-stimulating factor (GM-CSF) –based vaccine. Patients Methods Stage IV (n = 16) vaccinated autologous tumor-derived heat shock protein peptide complex gp96 (HSPPC-96) low-dose GM-CSF provided pre- post-treatment whole specimens. Peripheral-blood mononuclear (PBMCs) were flow cytometry, separated into cellular subsets, used for vitro proliferation assays. PBMCs from stage-matched 12) treated non–GM-CSF-based vaccines (ie, HSPPC-96 alone or interferon alfa/melanoma–derived peptides) o...