Leukapheresis is performed for advanced cancer patients who will undergo Dex therapy. Within a cell therapy unit GMP (good manufacturing practices) laboratory, monocytes are isolated following elutriation, and these are differentiated to immature DCs (iDC) by addition of GM-CSF and IL-4 in culture. iDCs may then undergo a quality control (QC) check before loading of MHC-I– and MHC-II–binding peptides in the presence of IFN-γ to generate mDC. Peptide-loaded exosomes from culture supernatants can then be isolated and concentrated by a process of centrifugation, diafiltration, and finally ultracentrifugation over a D₂O sucrose gradient. QC testing of immunological characteristics (e.g., tetraspanin content of Dex, MHC-II and costimulatory molecule levels) and immunostimulatory capacity (e.g., ability to stimulate a peptide-cognate T cell clone) is then performed for each preparation to determine whether a given batch can be released. Released batches may then be stored (–80°C) for therapeutic administration through intradermal (i.d.) injections. Production of Dex for immunotherapy takes approximately three weeks from the initial leukapheresis (this includes time for Dex manufacturing, QC testing, and treatment of the patient with metronomic cyclophosphamide).